r/.i £ou/vj> /i^ss HARVARD UNIVERSITY LIBRARY MUSEUM OF COMPARATIVE ZOOLOGY £^x ^/-/A nQ:E: 76, 'SU NOV 1 0 1931 MEMOIRS OF THE SAN DIEGO SOCIETY OF NATURAL HISTORY Volume 1 CATALOGUE OF THE MARINE Pliocene and Pleistocene MoLLUscA OF California AND ADJACENT REGIONS With Notes on Their Morphology, Classification, and Nomenclature and a Special Treatment of the Pectinidae and the Turridae (Including a Few Miocene and Recent Species) TOGETHER WITH A SUMMARY OF THE STRATIGRAPHIC RELATIONS OF THE FORMATIONS INVOLVED BY U. S. GRANT, IV AND HOYT RODNEY GALE SAN DIEGO, CALIFORNIA PRINTED FOR THE SOCIETY NOVEMBBB 3, 1931 1i ^ A ^ •Ci MEMOIRS OF THE SAN DIEGO SOCIETY OF NATURAL HISTORY Volume I Table of Contents page 1 1 List of Illustrations page 14 Index page 959 MEMOIRS OF THE SAN DIEGO SOCIETY OF NATURAL HISTORY Volume I CATALOGUE OF THE MARINE Pliocene and Pleistocene MoLLuscA OF California AND ADJACENT REGIONS With Notes on Their Morphology, Classification, and Nomenclature and a Special Treatment of the Pectinidae and the Turridae (Including a Few Miocene and Recent Species) TOGETHER WITH A SUMMARY OF THE STRATIGRAPHIC RELATIONS OF THE FORMATIONS INVOLVED BY U. S. GRANT, IV AND HOYT RODNEY GALE SAN DIEGO, CALIFORNIA PRINTED FOR THE SOCIETY November 3, 1931 X'rinted and Bound BY Sunset Press San Francisco, Calif. TO MISS ELLEN BROWNING SCRIPPS, PATRONESS OF SCIENCE AND EDUCATION, WHO HAS MADE POSSIBLE THIS PUBLICATION. PREFACE Preparation of the Material The compilation of the data and the formulation of the opinions that comprise this volume were begun by the authors during the preparation of a joint dissertation to be submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Leland Stanford Junior University. The magnitude of the work, however, prevented its completion in the two years devoted to it before the authors received their degrees and necessitated more than a year of additional work to fill in partially the largest gaps. There is still much remaining to be done, and five or ten years more would be required to treat all the gi-oups of moUusks with the same thoroughness that is now given some of the more important groups. Nevertheless, it is believed that the material already collected will be found of sufficient value to warrant publication at this time. The original plan was to study and report on the paleontology and stratigraphy of the marine Pliocene and Pleistocene merely of the Ventura basin of southern California; but shortly after the field and laboratory work was begun, it became apparent that in order to arrive at a proper comprehension of the significance of the fauna in that region, it would be necessary to make a comparative study of many other Pacific coast species belonging to the genera represented. This necessitated a review of all the important literature on the Neocene paleontology of California and adjacent regions as well as most of the important papers on the local Recent mollusca. So much important and inter- esting information was thus accumulated that in order to make it readily available to future workers the scope of the paper was enlarged to include it. Scope of the Work This volume is divided into two parts. The first is a summary of the stratigraphic relations of the beds in which the fossils that are recorded in the second part were found, based not only upon an interpretation of the evidence offered by the fossils themselves but upon opinions derived from as many other different kinds of evidence as could be brought to bear upon the subject. In the second part an attempt is made to list every species and variety of marine mollusk known to occur in the Pliocene and Pleistocene deposits of California. In this part references are given to the original descriptions of species and varieties and to papers containing fossil records or other important informa- tion. The records of occurrence are outhned below the references, and in many cases the location of the type specimen and the type locality of the species are given. So far as time and space allowed, descriptions or brief diagnoses or comparisons have been added, as well as information about the genera and larger problems of classification. Often it has been necessary to revise the classification and nomenclature, and much more work in this direction is needed. Because of intimate relationships with the fossils of the California Pliocene and Pleistocene, most of the mollusks of similar age from Lower California, Mexico, and the region north of California to and including Alaska, and also some species from the Miocene and Recent faunas, have been added. 8 San Diego Society of Natural History [Memoirs Division of the Work The order of the names on the title page is not intended to indicate seniority of authorship. The first or stratigraphic part was written by Mr. Gale and the ideas expressed in it were brought together entirely by him; but Mr. Gale wishes to acknowledge the advice and assistance in looking up certain points, especially in the San Diego region, given him by Mr. Grant and others. Considerably more than half of the second or systematic paleontology part, except the introduction, was written by Mr. Grant, with here and there a comment or the treatment of a single species by Mr. Gale. In most groups, however, revisions of the classifications or nomenclature were worked out by the writers together, as in the Pholadidcp, MarginellidcE, Neptmieida;,Pyrenidce, Muricidoe, Cymatiidce, Naticidce, etc. The changes in the classification of the Arcidoe, Madridce, and Veneridce, and the specific rearrangements in those families and in the TelUnidce and CanceUariidce are in large part due to Mr. Gale; and certain groups, more particularly the Pedinidce, the Myacea, Siliqua, the Turridce, and Ficus were written by Mr. Gale and are almost wholly his work, though Mr. Grant contributed valuable assistance in procuring references and lending advice on the comparison of specimens and species. The two authors co-operated in the compilation of the fossil and other records of all the species. Field work and collecting were done by Mr. Grant principally in the Pleistocene of the western end of the Ventura basin, but also a little near Goleta, Newport Beach, and San Diego; and by Mr. Gale principally in the Pliocene of the eastern or upper end of the Ventura basin. The latter author has also examined well cores from the southern part of the San Joaquin basin. Acknowledgments The writers are indebted to a number of persons and institutions for assistance in preparing this memoir. Under Professor Percy E. Raymond, of Harvard University, both writers received their introductions to paleontology, and a number of the ideas that they believe will prove most helpful in the future, especially to students of strati- graphy and paleontology, can be traced to their source in Professor Raymond. To the late Professor James Perrin Smith, of Stanford University, they are particularly indebted for suggesting the work, for watching its progress, and for giving from time to time when most needed that kind of enthusiastic encouragement that has been the inspiration of many of the best geologic and paleontologic productions in California and to which they would ascribe a large part of the credit for whatever may prove of value in this volume. Mrs. I. S. Oldroyd, Curator of the Collections of Recent Mollusca at Stanford University, has assisted in many ways, by explaining to the writers, especially when they were beginning their study, the forms and names of many Recent species and by pointing out many times the arrangement of the collections. Dr. Hubert G. Schenck, also of Stanford University, has always been ready to help in any way possible and has repeat- edly called attention to important literature that might otherwise have been overlooked. Thanks are also due to Mr. A. M. Strong, conchologist of Balboa, California, for informa- tion and advice about some of the smaller gastropods; to Mr. George Willett, of the Los Angeles Museum, for information on some of the northern Recent mollusca; to Professor B. L. Clark, of the University of California, for the most cordial co-operation and liberal permission to examine any of the material in his charge; and to Mrs. Kate Stephens, Curator of Mollusks at the San Diego Society of Natural History, for information and the loan of specimens. Dr. W. P. Woodring, of the California Institute of Technology, Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 9 has also helped the writers, especially in matters of nomenclature. Dr. W. S. W. Kew and Dr. Frank Hudson, geologists of Los Angeles, have been very kind in criticizing the manuscript of the stratigraphic part of this memoir; and Mr. J. E. Eaton, also of Los Angeles, has aided by donating specimens and showing the writers collecting localities. Of indispensable assistance was the large collection of Recent shells at Stanford University, to which the wTiters were allowed limited access. The paleontological collec- tions at Stanford University, under the charge of Professor Smith, were available at any time and were also a valuable assistance. Other institutions have been most liberal in allowing the use of their materials. At the University of California, the writers were allowed access to all the collections and entrance to the library stacks, through the kindness of Professor Clark and the late Professor W. D. Matthew. At the California Academy of Sciences, Dr. B. W. Evermann, Director of the Museum, and Dr. G. D. Hanna and Dr. L. G. Hertlein, of the Department of Paleontology, gave the wi'iters permission to study the collections and make use of the library. Mr. C. G. Abbott, Director of the Museum of the San Diego Society of Natural History, permitted the Society's library purchases for nearly two years to be guided by the library requirements of the writers, and for this very important help the writers are especially grateful. Dr. Alexander Wetmore, Assistant Secretary of the Smithsonian Institution in charge of the U. S. National Museum, Dr. R. S. Bassler, Curator of Geology in the U. S. National Museum, and Mr. W. C. Mansfield, Assistant Curator of Mollusks, have all been very obliging in furnishing information and photographs of specimens. Mr. E. G. Vanatta and Dr. H. E. Pilsbry, of the Academy of Natural Sciences of Philadelphia, have given similar assistance. The Widener Library at Harvard University has been very accommo- dating in supplying promptly photostats of rare publications. Sir J. R. LeB. Tomlin, of the British Museum, and Mr. Arthur E. Wrigley, English conchologist, have kindly given information difficult to procure in this country. For the privileges and help noted above, the WTiters wish to express their sincere thanks. To Dr. W. A. Bryan, Director, and Dr. J. E. Comstock, Associate Director, of the Los Angeles Museum, the authors are indebted for permission to use the collections and library under their charge in making late additions and corrections to the manuscript and galley proofs. To Miss Ellen Browning Scripps, of La Jolla, California, the ^Titers are much indebted for her generous aid, which has made possible the publication of this contribu- tion without the substantial abridgement in size and in subject matter that would other- wise have been necessary. As one of the many benefits resulting from Miss Scripps' sincere interest in science and education, it has been possible to include discussions and explanatory matter which it is hoped will prove of value to university students and to those who are beginning their studies of California paleontology and stratigraphy. To Dr. Fred Baker, conchologist of Point Loma, California, and Vice-President of the San Diego Society of Natural History, the writers also wish to express their appreciation for aid in securing immediate publication of this report, as well as for helpful advice and the loan of material. Both writers also wish to express their indebtedness to Mrs. Hoyt Rodney Gale for her valuable help in the tedious work of proof-reading and in preparing the index. Purposes of the Work Besides the merely mechanical compilation of information so that later students could have more ready access to the material available, the writers have attempted to broaden the outlook of the whole subject by introducing more information from distant 10 San Diego Society of Natural History [Memoirs or foreign sources, by noting occasionally the intimate relations between fossil and living molliisks of the Pacific coast of North America and fossil and living mollusks of other parts of the world, and by trying to substitute for the unfortunately too common and altogether unscientific guessing about the magnitude of the differences necessary to separate new species a greater consideration of mollusks, both fossil and living, as zoologic entities of necessarily variable characters. Coming from one part of the country to an- other, the writers had, perhaps, a special advantage and a special incentive in trying to avoid the evils of provincialism. The failure to go more than a short distance toward the aims just mentioned must be ascribed in large part to the writers' limited time, material, and experience but not in any significant degree to defects in the aims or principles worked upon. Such errors as have necessarily found a place in this report, and there are undoubt- edly many, the writers desire to have corrected. It is hoped that at some later date it will be possible to publish a supplement with corrections and additions. In all respects the writers have tried to make this catalogue as useful as possible to all classes of students. CONTENTS ' PAGE Preface 7 Preparation of the Material 7 Scope of the Work 7 Division of the Work 8 Acknowledgments 8 Purposes of the Work 9 Part I. Summary of the Stratigraphy 19 Introduction 19 Methods of Correlation 20 Relation of Historic to Current Methods 20 First Appearance and Extinction of Species 20 Climatic Changes 21 Sedimentary Cycles 23 Effects of the Profile of Equilibrium on Sedimentation and Cor- relation 24 Correlation of Marine Terraces 24 Conclusion of Remarks on Correlation 26 Description of Local Sections 26 The Ventura Basin 26 The Los Angeles Basin 39 The San Diego Basin 45 Coyote Mountam and Lower California Localities 49 The San Joaqum Basin 51 The Sierra Nevada 53 The Coasts of Middle and Northern California 54 The Coast of Oregon and Northward 56 Historical Summary of Conditions in California 57 Correlation with the European Standards 66 The European Section 66 Comparison of California and European Sections 68 Concluding Remarks 77 Part IL Systematic Paleontology 81 Introduction 81 The Mechanics and Accomplishments of Paleontologic Study 81 Nomenclature 82 Classification 85 Variation 90 Migration of Species 93 Bibliography 98 San Diego Society of Natural History Fossil Localities 101 12 San Diego Society op Natural History [Memoirs PAGE Systematic Catalogue, mth Discussions of Species and Genera 109 Pelecypoda 109 Scaphopoda 436 Gastropoda 440 Amphineura 878 Explanation of Plates 880 Index 959 New Generic, Subgeneric, and Sectional Names Truncadla, section H^ Kalayoldia, section 128 Vertipeden, subgenus 188 Humilaria, subgenus 325 Megapitaria, subgenus 346 Varicorbula, subgenus footnote on 420 Scobinopholas, section 431 Clinopegma, section 660 Exiliaidea, genus 665 Striomitrella, section 698 Centrifuga, subgenus 706 Murithais, subgenus 729 New Specific and Varietal Names Nucula {Acila) semirostraia 113 Area {Area) trilineata Conrad variety ealcarea 140 Area {Area) perlabiata 141 Area {Navicula) terminumbonis 142 Glans minuseula 277 Irus lamellifer (Conrad) variety prelamellifer 332 Dosinia ponderosa (Gray) variety longidens 353 Macoma planivscula 372 Mactra {Macira) orihoviorpha 391 Analina {Raeta) pUcateUa (Lamarck) variety longior 408 Mya {Mya) arenaria Linnteus variety profundior 414 Corhula {Corbula) gibbiformis 420 Acteon {Rictaxis) painei Dall variety grandior 444 Pseudomelatoma penicillata (Carpenter) variety semiinjlata 561 Moniliopsis incisa (Carpenter) variety quinquedncta 568 Mangelia {Mitromorpha) crassaspera 599 CaneeUaria obesa Sowerby variety planospira 613 Mitrella grandior 696 Thais {Nucella) elsmerensis 719 Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 13 PAGE Fims {Trophosxjcon) ocoyana (Conrad) varietj^ ruginodosa 746 Ficiis (Trophosycon) ocoyana (Conrad) variety contignata 749 Ficus (Trophosycon) dallamensjs Weaver variety nodibulbosa 751 "Cerithium" simplicius 757 Bittiuvi (Lirobittium) aspervm (Gabb) variety dilatatum 760 Architectonica nobilis Bolten variety discus 786 Astrcea {Pomaulax) gradata 818 Tegula (Chlorostoma) dubiosa 827 Families That Have Received Particular Attention (The writers found these families greatly in need of revision and many other famiUes in a condition that was hardly any better. Much more work will be required to eliminate obvious inconsistencies, to recognize the true relation- ships, and to consolidate synonyms, both in these families and in all the others.) Arcidce, more or less suljgeneric and specific rearrangement 133-144 PectinidcE, reclassification of species and varieties, with some rearrangement of subgenera; notes on variation and interregional migration of species; in Lyropecien, Vertipecten, Amusium, etc., brief notes on phylogeny 154-238 Carditidce, nomenclatorial rearrangement 272-279 Codakndce ( + Ungidinidce), temporary, makeshift, nomenclatorial rearrangement 283-297 Cardiidce, generic and subgeneric nomenclatorial changes 302-315 Veneridce, generic and specific reclassification begun 315-354 MactridcB, disentanglement of some of the specific synonymy and changes in the assignment of species to genera and subgenera 390-410 Turridce, morphologic and nomenclatorial reclassification of genera and species, with notes on apparent genetic relationships which may be useful in working out the phylogeny . . . 477-612 Cancellariidce, specific rearrangement 612-623 Marginellidce, generic rearrangement 628-633 NeptuneidcE (part of the Buccinidce ?), incomplete generic rearrangement 642-667 Nassariidoe, more or less rearrangement 670-679 Pyrenidce, generic reclassification 679-704 Muricidce, mcomplete generic rearrangement 704-731 Cymatiidw, generic rearrangement 732-739 Ficidce, revision of species and varieties 741-751 LIST OF ILLUSTRATIONS PAGE Diagram A. Sketch Map Showing the Ventura Basin 27 Diagram B. Generahzed Section of Ventura Basin Miocene-Pleistocene Sediments Elim- mating Effects of Pleistocene Deformation 31 Diagram C. Ideal Diagram Showing Marme Erosion and Marine Deposition Acting Simul- taneously in the Pliocene and Pleistocene of San Diego 47 Diagram D. Horizontal Cross-Section of the Turrid Family Tree 481 Table I. Correlation of California Formations 61 Table II. Correlation between California and Europe 69 Table III. Correlation of Glacial Ages ^ 75 Text Figures: 1. Nucula (Acila) gettysburgensis Reagan 113 2 and 3. Nucula (Acila) semirostrata, new species 114 4. Nucula (Acila) sp 115 5. Hinges of Paphia ala-papilionis Bolten and PapMa (Tapes) litterata (Lin- naeus) 325 6. Mitrella scripta (Linnaeus) 690 7. Mitrella rosacea (Gould) 691 8. Aesopus japonicus Gould 703 9. A Naticoid shell illustratmg the application of descriptive terms 796 10. Natica (Natica) unifasciata Lamarck 797 11. Natica. (Tectonatica) clausa Broderip and Sowerby 798 12. Polinices (Polinices) uber (Valenciennes) 799 13. Polinices (Neverita) reclusianus (Deshayes) 801 14. Polinices (Neverita) reclusianus (Deshayes) variety callosus (Gabb) 803 15. Polinices (Euspira) leivisii (Gould) 804 Plates 1-32 880 Figures of the Types of Old Species, Varieties, or Stnonyms Pecten (Aequipecten) purpuratus Lamarck variety cristobalensis Hertlein pl- 5, fig. 2 Pecten (Aequipecten) purpuratus Lamarck variety hakei Hertlem pl- 8, fig. 3 Dosinia longula Conrad pl. 22, fig. 1 Anatina (Raeta f) transmontana (Conrad) pl. 22, fig. 2 Dosinia niontana Conrad pl. 22, fig. 3 Dosinia subobliqua Conrad pl. 22, fig. 4 Pecten (Patinopecien) propaiulus Conrad pl. 22, fig. 5 Schizothcerus nut'.allii (Conrad) variety pajaroanus (Conrad) pl- 22, fig. 8 Surculites (Megasurcula) carpenterianus (Gabb) variety cooperi^ (Arnold) pl. 25, fig. 3 Lora declivis (Loven) variety oldroydi (Arnold) pl. 25, fig. 20 Mangelia (Mitromorpha) gracilior (Hemphill in Tryon) [type ?] pl. 25, fig. 22 Cancellaria newhallensis Carson ( = C. tritonidea Gabb variety ato'sptra Gabb) pl. 27, fig. 7 Cancellaria perrini Carson ( = C. tritonidea Gabb) pl. 27, fig. 8 AstroRa (Pomaulax) turbanica (Dall) pl. 31, fig. 2 Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 15 Nuculana (or Yoldia) astoriana (Henderson), new name for Nucula impressa Conrad. pi. 32, figs. 46, 47, 48 Area obispoana Conrad pi. 32, fig. 49 Reproductions of the Original Figures of Type Specimens Pecten {Pallium) swiftii Bemardi pi. 10, figs, la, 16 Tivela stuUorum (Mawe) pi. 19, fig. 8 Lcevicardium (Cerastoderma) corbis (Martyn) pi. 19, fig. 14 Macoma krausei Dall ( = M. moesta (Deshayes)) pi. 20, fig. 3 Mangelia striolata Risso pi. 25, fig. 18 Mangelia (Bela) menardiana Risso pi. 25, fig. 21 Clavus iClathrodrillia) gibbosus (von Born) pi. 26, figs. 3a, 36 Clavus {Crassispira) bottoe (Valenciennes in Kiener) pi. 26, figs. 6o, 66 Clavus {Cymatosyrinx) lunaius (Lea) pi. 26, fig. 7 Hemipleuro'.oma archimedis (Bellardi) pi. 26, fig. 36 Thais (Nucella) lima (Martyn) pi. 32, fig. 15 Calliostoma costatuni (Martjai) pi. 32, fig. 25 Figures of Species or Varieties Hitherto Unfigured or Poorly Figured or Figured only IN Rare or Obscure Publications, and Other Figures to which Special Attention Is Called Mitrella rosacea (Gould) text fig. 7, p. 691 Aesopus Japo7iicus Gould text fig. 8, p. 703 Pecten {Janira) stearnsii Dall variety bakeri Hanna and Hertlein pi. 4, figs, la, 16 Pecten {Patinopeeten) purisimaensis Arnold pl- 6, fig. 3 Pecten {V eriipecten) nevadanus Conrad pl- 7, figs. 2a, 26, 2c Pecten {Lyropecten) magnificus Sowerby pl- 9, fig. 1 ; pl. 10, fig. 6 Crassatellites antillaru7n (Reeve) pl. 13, figs. 7a, 76 Calyptogena pacifica Dall pl. 13, figs. 13a, 136 Lucina (Myrtea) californica Conrad pl. 14, figs. 15a, 156, 21a, 216 Lcevicardium (Cerastoderma) decoratum (Grewingk) pl. 19, fig. 12 Macoma carlottensis Whiteaves pl. 20, figs, la, 16, 2a, 26 Surculites {Surcidites) mjnootcheensis (Weaver) pl. 25, fig. 2 Clavatula coronata (Chemnitz) Lamarck pl. 25, figs. 16a, 166 Daphnella claihrata Gabb pl. 25, figs. 23, 24 Moniliopsis graciosana (Arnold) pl. 26, figs. 12, 13 Anachis (Chativetia) lineolata (Gray in Reeve) pl. 26, figs. 31, 34 Nassarius (Uzita) arnoldi (Anderson) variety ivhitneyi (Trask) pl. 26, figs. 48a, 486 CanceUaria hemphilli Dall pl- 27, figs. 3, 15a, 156 Admete modesta (Carpenter) pl. 27, fig. 5 Mitra catalince (Dall) pl. 28, fig. 4 Neptunea {Neptunea) andersoni (Martin) variety hawleyi (Carson) pl. 28, figs. 9o, 96, 9c Astrea {Pomaidax) turbanica (Dall) pl. 31, fig. 2 Chicoreus (Murithais) wilkesanus (Anderson) pl. 32, fig. 12 Terebra (Strioterebrum) albocincta (Carpenter) variety hindsii (Carpenter) pl. 32, fig. 35 PART I SUMMARY OF THE STRATIGRAPHY PART I SUMMARY OF THE STRATIGRAPHY Introduction The following summary of the stratigraphic relations of the various formations from which fossils are reported in the systematic paleontology part of this memoir is offered here as an explanation and interpretation of the fossil occurrences. Original field work in preparation for this summary has been done only in some districts of southern California, so that part of the material presented here had to be based on a reinterpretation of the literature. As space does not allow a discussion of the details of the stratigraphy in the various regions dealt with, additional facts and complete proof of some of the generaliza- tions here offered are to be sought in the literature referred to. The study of the mollus- can record assisted by other available information has yielded some new points of view on the later Cenozoic history of California that are believed to be of considerable importance. It is possible to recognize in California major marine cycles in the Miocene and Pliocene that can be correlated with the major marine cycles of Europe not only by means of fossils but also by means of the physical similarity of the cycles. California equivalents of the four European glacial ages and the corresponding interglacials can be pointed out and correlated on the basis of climatic changes. There is evidence to show that the later Cenozoic orogenic movements that produced the structures of the Coast Ranges were confined to a comparatively limited period of time, the beginning and end of which can be approximately dated; and the isostatic readjustment of the different crustal blocks can be recognized as caused by and subsequent to the orogenic movements. The correlation of the Pleistocene glacial ages with those of Europe will afford an estimate in years, which, though very rough, will allow a crude quantitative estimate of the relative amount of work that the different geologic processes could have done during each of the various ages. For instance, it will give perspective to the current conceptions of the work of the ocean in cutting terraces during the later Pleistocene, and will emphasize the insignificance of the work done on the remnants of the terraces that are now exposed to view and the tremendous amount of work that must have been done on terraces that have been removed by later terrace cutting or have been hidden below sea level. Thus it will lead to a more precise visualization of the broad terrain of uplifted and depressed blocks that extended perhaps even to the edge of the continental shelf in fairly late Pleistocene time. In the following treatment of the subject a few pages will be devoted to a discussion of the methods of correlation employed. Then a brief description of representative dis- tricts in California will be given, followed by a general summary of the correlations between districts with an outline of the later Cenozoic history of California. Finally will come a brief description of the European section and an explanation of the proposed correlations between California and Europe. 20 San Diego Society of Natural History [ Memoirs Methods of Correlation Belation of Historic to Current Methods The earliest correlations between geologic formations were made by tracing strata along their surface outcrops and noting the differences in lithology. Afterwards it was discovered that the fossils in some beds are different from those in others, and the fossils were used locally like the lithologj' to distinguish beds. These early methods were later expanded and applied to rock exposures that are not directly connected; and in the course of time similar sequences of lithologic units and similar sequences of fossil horizons came to be recognized as more reliable indications of correlation than similarities in single units. Furthermore, it was recognized that lithologic units may recur at various horizons but that faunal units usually do not, and the theory was formed that the differences in the latter were due to the extinction of old species and the evolutionary development of new. Other methods of correlation were added, particularly the use of unconformities and of the relative amounts of deformation and erosion. These classic methods have been extremely useful, especially among the older formations of Europe and eastern North America where deposition was comparatively regular and comparatively slow, and where sufficient time elapsed between the deposition of successive formations for important evolutionary changes to take place. However, even in the older formations these methods have not always been sufficient, so that others have been sought; and in Cenozoic formations, especially in the later Tertiary and Quaternary of regions like California where violent deformation has taken place in almost modern times, deposition has been so rapid and irregular, and evolutionary changes have been so slight that other criteria are needed for a satisfactory working out of the geologic history. In the Pliocene and Pleistocene of California the lithology of the oldest beds may not differ materially from that of the youngest ; and all the deposits but the very latest Pleistocene have shared equally in the only deformation that is clearly of widespread significance. The Pleistocene faunas contain practically no species of mollusks that have not left living descendants, and the Pliocene faunas contain only a few. As there are, however, even under such conditions certain very useful criteria for distinguishing the various horizons, it is worth while to consider to what extent the older conceptions can be applied and to what extent they have been altered or replaced by new. First Appearance and Extinction of Species Lyell's classification of the Cenozoic according to the number of living species in each division as compared with the number in that division that are now extinct is well known. The method of correlation upon which this classification was based can be used, however, only in a rough way and is useful only when the extent of the knowledge of the living fauna is taken into account and also the personal equation of the individual who has determined the species of the fossil fauna. The value of the method varies in the different parts of the geologic time scale to which it has been applied. Of the Pleistocene species from San Pedro that were thought to be extinct, the majority have now been found living or have been identified with living species, especially those of the Turridce, which once formed a considerable part of the supposedly extinct species. The cold-water horizons were thought to be older than they are now believed to be because the northern faunas were formerly not so well known. Crepidula princeps alone among the species represented in cold-water faunas is nominally extinct, being very closely related to its northern descendant, C. grandis. Of the other important Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 21 Pleistocene species supposed to be extinct, there remain only Cantharus fortis and Can- cellaria tritonidea; and even these two species have living representatives in Cantharus insignis (Reeve) from Colombia and Cancellaria cassidiformis Sowerby from Panama. It may be only a question of time before living variations will be found that exactly match the fossil. Rarer species are still less to be relied upon in making correlations, because in many cases they are only peculiar forms of better kno"vvn species, and because, even if they really are distinct, their significance cannot be determined on account of their rarity. Thus, for distinguishing the horizons of the Pleistocene from each other and from the Recent, if extinction of species alone were depended upon, only a few varieties and closely related forms of doubtful value could be used. In the Pliocene, however, the approaching cold of the glacial epochs caused extensive migrations of faunas and the extinction even of some of the important species. Peden beUus and Peden opuntia are notable among the species that persisted into the cold-water zone that is here referred to the uppermost Pliocene, and then disappeared. In the middle Pliocene there are a number of warm-water species that are not known in later deposits. Among the most important are: Area trilineata, Madra (Spisida) albaria, Madra (Pseudo- cardium) densata, Mytilus coalmgensis, Ostrea atwoodi, Peden (Patinopedeti) coosensis variety dilleri, Peden {Patinopeden) healeyi, Peden (Lyropecten) estrellanus variety cerro- sensis, Venus (Chione) securis variety fernandoensis, Astroea {Pomaulax) gradata, Can- tharus humerosus, and Turritella vanvlecki. The varieties listed are believed to be the last representatives of older species. In addition, the species known living only in Japan should be added : Pecten {Pallium) swiftii and varieties, and Cancellaria hemphilU ( = ? thomasiana Crosse). In the lower Pliocene there are but a few more to increase the number of important Pliocene species that have become extinct: Area terminuynbonis, Peden purisimaensis (another variety of coosensis ?), Ficus (Trophosycon) ocoyana varie- ties, Thais imperialis, and the species probably still living in Japan, Psephcea oregonensis ( = ? prevostiana Crosse). The Ficus is found in the lower Pliocene of various localities and also at the base of the San Diego section where it might be assigned tentatively to the middle Pliocene. Thus, it is seen that the most important break, the only horizon where the extinction of species is of any considerable help, comes at the first appearance of cold temperatures toward the end of the Pliocene epoch. The number of extinct species in the Pliocene is already known to be much less than half of the total so far recorded from the Pliocene; and as the living faunas of western Mexico and Central America, where many of the middle and lower Pliocene species are now living, are still imperfectly known, it is to be expected that even more of the sup- posedly extinct species will be found alive. In the Miocene a much larger proportion of the species are extinct; but survivors of species formerly supposed to be extinct keep turning up in southern waters, usually of course in the eastern Pacific but sometimes in the Orient and sometimes even in the Atlantic, so that it is somewhat doubtful whether as many as half of the species are extinct. Peden crassicardo, for instance, appears to be living in the Galapagos Islands as P. 7nagnificus ; and the Oligocene Nucula gettys- burgensis apparently is living in Japan as N. mirabilis Adams and in India as A^. fultoni Smith. Climatic Changes In the late Tertiary and even more in the Pleistocene, climatic changes have provided a means of correlation that is superior to that afforded by the extinction of species. At times, of course, the two go together, as when toward the end of the Pliocene the lowering 22 San Diego Society of Natural History [ Memoirs of the temperatures was the principal cause of the extinction of species. Carpenter, Dall, Smith, Arnold,' and others have long recognized the presence of rather marked climatic changes as an important characteristic of the later Tertiary and the Quaternary of California, and_ the importance of these changes is to be emphasized here even more than has usually been done. The correlation of the various formations deposited along the Pacific coast of the United States from the Miocene to the Recent has been made possible perhaps as much by climatic changes as by the extinction of species. Sometimes paleontologists have made use of the differences in the thermal facies of faunas without realizing what they were doing. To the older writers who had little opportunity to know the faunas living northward and southward from the boundaries of the United States and to modern workers who do not believe that specimens coming from widely separated localities can belong to the same species, a fossil fauna representing a climatic extreme has the appearance of containing more extinct species than it really does and hence of being older than it really is. Only so long as the older formations were deposited under more extreme climates than the younger has this lack of knowledge or the equivalent erroneous assumption led to the correct conclusions. It seems to have made little difference for comparative purposes in California whether the species of the warm-water Miocene and lower Pliocene are extinct or have merely migrated to southern waters; but in later times when the climate fluctuated from warmer than at present to colder, and then warmer again, and must have passed several times through stages when the conditions were approximately the same as at present, it is to be expected that the faunas of such times would be more like the faunas now living off the coast in the same latitudes than were the faunas that lived during some of the intervening or succeeding intervals. Here may lie the explanation of why there was thought to be a greater number of extinct species in the upper than in the lower Pleistocene of San Pedro. Furthermore, in correlating deposits of different latitudes the climatic factor must be taken into account; and it must be recognized that during times when the average temperatures were gradually falling, the faunas of northern latitudes may resemble in some respects the later faunas of lower latitudes. It may be for this reason that the Empire formation of Oregon and its equivalent, the Montesano formation of Washington, were assigned by Howe^ to the Pliocene, whereas they have generally been considered upper Miocene and are tentatively considered upper Miocene in this paper. Similarly, when the effects of the shifting of climatic zones up and down the coast are taken into account, it is easier to understand how such a form as Pecten caurinus can be a useful guide fossil in the uppermost Pliocene of southern California although it is still Hving in the Northwest and may even extend back to the Miocene in that region. In other words, climatic changes are a fundamental cause of the differences in faunas and should be taken into account along with the extinction of species. Not only are the changes in past climates useful in making more detailed local correlations, but there is reason to believe that they have been very widespread in their effects so that they may be used as accurate guides for making correlations with distant regions. They provide in the later Tertiary and Quaternary the best criteria yet found for establishing exact time equivalence. This subject will be discussed later in connection with the proposed correlations between the California and European sections. ' Arnold, R.: "Environment of the Tertiary Faunas of the PaciBc Coast of the United States," Journal of Geology, Vol. 17, pp. 509-533, 1909. Smith, .1. P.: "Climatic Relations of the Tertiary and Quaternarj- Faunas of the California Region," Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, pp. 123-173, 1919. • Howe, H. v.: "Faunal and Stratigraphic Relationships of the Empire Formation, Coos Bay, Oregon," Univ. Calif. Publ. Geol., Vol. 14, pp. 85-114, 1922. VoLDME I ] Pliocene and Pleistocene Mollusca of California 23 Sedimentary Cycles Another means of dividing geologic deposits into natural units and of aiding in the correlation of formations, a means too often overlooked or disregarded, is provided by the physical relations of the beds themselves. In order to have a marine deposit laid down in a region that previously has been subjected to erosion or to continental deposi- tion, it is necessary for marine waters to transgress over the land; and during this process they often leave easily recognizable littoral deposits or basal conglomerates at the contact with the underlying formation. Also, if we are to see the deposit at all, it is necessary for the sea to have withdrawn at some time from the area, leaving behind it another zone of littoral deposits which ma}' or may not have been preserved. Such a series of events is known as a sedimentary cycle. If the transgression and regression are extensive enough it is known as a major cycle, but if not, as a minor cycle or oscillation of the shore line. In California there appears to have been one well-marked major cycle in the Miocene and another in the Pliocene, and so far as can be determined the beginnings and endings of these cycles are coincident with the beginnings and endings of the time divisions in the European section. Just why the relations of land and sea should be the same in such widely separated regions it is impossible to state, for too little is known about the physical forces of the interior of the earth. It is not impossible that the land remained relatively stable in the two regions and that the sea level varied (eustatically) according to the elevation or depression of the ocean bottom in other parts of the world, that the relative elevation of the oceans and continents is dependent upon some still unknown igneous cycle. On the other hand, the accumulation of horizontal pressures in the earth's crust may have been transmitted throughout wide, perhaps even world wide, areas, affecting the weaker portions of the crust in remote parts of the earth in varying amounts but at essentially the same time. In spite of statements to the contrary, it seems probable that California as well as northwestern Europe remained relatively stable during the Miocene and during the Pliocene and that the only widespread deformation in California that would upset the orderly sequence of sedimentary cycles did not come until the middle of the Pleistocene.' Of course locally the relations are complicated by minor earth movements and toward the edges of basins by minor oscillations of the shore lines, but if viewed comprehensively the sequence seems to be remarkably simple. Even if the similarity between the California and the European sections is nothing more than a coincidence, as long as the paleontologic and climatic evidence seems to support the essent al contemporaneity of the major divisions of the two, it is desirable for practical purposes to consider them the same. The subject of sedimentary cycles is briefly explained and illustrated in a little book by Stamp.- Of California authors, apparently the only one who has expressly considered this subject is Dr. Louderback of the University of California. His paper on the Miocene cycle^ may not have all the details explained correctly and everyone may not agree with the nomenclature used, but the general principles involved and the general history of events are described more clearly in this paper than they are in other California publi- cations. ^ The post-Miocene deformation seems to have been chiefly a gentle warping of the land surface, only locally severe, and it seems to have come at a time when the Miocene cycle was naturally drawing to a close through the filling up of the basins of deposition. The California Pleistocene deformation may have been accompanied by contemporaneous movements in the Alps and in other parts of the world, and may be of more than local significance. The California Upper Miocene deformation may even be a reflection of the Alpine revolution. ' Stamp, L. D.: "An Introduction to Stratigraphy (British Isles)," London, 1923, especially pp. 12-19, 268-310. ' Louderback, G. D.: "The Monterey Series in California." Univ. Calif. Publ. Geol., Vol. 7, pp. 177-241, 1913, especially pp. 232-241. 24 San Diego Society of Natural History [ Memoirs Effects of the Profile of Equilibrium on Sedimentation and Correlation The profile of equilibrium is the submarine surface above which sediment cannot rest without being again disturbed by wave action, unless the prevailing conditions are changed. If the waves are cutting a plane of marine denudation along the shore line, they cut down to the profile of equihbrium. If material is being deposited, it is deposited up to the profile of equilibrium. When an area of deposition is filled up to the profile of equilibrium, deposition ceases in that locality and the material is carried farther out to deeper water. Thus there are gaps in the sedimentary record, gaps that represent a time when the area was still under water and are quite different from unconformities or disconformities as usually understood. These gaps, known as diastems, may represent whole geologic periods, lasting as long as the relations of land and sea are constant. Deposition usually takes place from the shore outward, with a small original dip seaward. If the sea level is lowered, the profile is lowered and the upper (shoreward) ends of the beds are truncated. If the sea level rises again, the beds of the new series will rest, perhaps with slight angular unconformity, on the oldest as well as on the young- est beds of the older series. Even a big storm causes a temporary lowering of the profile of equilibrium, with the accompanying scour and later refill. Thus it is easy to see how minor changes in conditions complicate the sequences in marine near-shore deposits, causing mixtures of material of different ages and accounting for the anomalies in such occurrences as the Pleistocene beds at San Pedro, .where the details (though not the major events) of warm and cool water faunas seem to be almost hopelessly jumbled and indicate events that probably have little geologic significance. This aspect of sedi- mentation has been considered in a recent article by Eaton;' but as a rule it has been almost entirely ignored, strange to say, in California where it is most important. The San Pedro irregularities were described in a recent paper by Crickmay, which is discussed later. Correlation of Marine Terraces The marine terraces exposed along the coast of California appear to be of two kinds. One kind of terrace is formed after a comparatively rapid rising or sinking of the land in respect to sea level. A rapid depression of the land causes the waves to attack the slopes of the drowned terrestrial surfaces, slopes which are usually steeper than the normal slope of the submarine profile of equilibrium. A rapid elevation of the land causes the waves to attack the also comparatively steep slope at the outer end of the profile of equilibrium. In either case, the waves work on the edge of a body of water that is abnormally deep near the shore; and as a result, deposition begins at the initial shore line, working outward, and the cutting action of the waves is mainly horizontal. Such a process produces a bench many miles or only a few hundred feet in width according to the length of time the land and sea maintain the same relative position. The inner edge of the bench becomes a steep cliff. Such is the nature of the present shore line of California, due in most cases to a comparatively recent sinking of the land. The other kind of terrace is formed only during a period of prolonged but very gradual uplift by a slight acceleration in the rate of uplift. If the ocean has developed a very long and very gently sloping profile of equilibrium so that the water remains ^ Eaton, J. E.: "The By-Passing and Discontinuous Deposition of Sedimentary Materials," Bull. Amer. Assn. Pet. Geol., Vol. 13, pp. 713-761, 1929. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 25 shallow far from land, then a very gi'adual uplift of the land causes the wave action to expend its energy in lowering the bottom, and the ocean can no longer cut back the shore line. The ocean may even lose ground and be forced to withdraw its shore line gradually, leaving behind littoral deposits. In that case a slight increase in the rate of uplift causes a more rapid retreat of the shore line and produces a terrace with more gentle slope merging with the steeper slope above. Perhaps a later return to the more gradual rate of uplift may cause the slope to become steeper again at the outer edge of the terrace, and the changes in slope may continue indefinitely with the formation of numerous terraces separated by steeper slopes. The steepest slopes represent the times of most gradual marine retreat. Such is the explanation of the terraces forming the Burton Mesa of the Santa Maria district and the lower terraces at San Diego. In each case, where preserved, a thin conglomeratic sandstone covers the tops of the terraces and the slopes between them with a continuous blanket of littoral deposits left behind by the retreating sea. Of course, if the uplift become still more rapid, the shore line may retreat at once to the outer end of the old profile of equilibrium, and then the waves can begin to cut back horizontally the other kind of terrace, with a steep cliff at the back on which are no marine deposits. The two kinds of marine terraces are, however, not so fundamentally different as might at first appear. The difference is partly in the emphasis laid in the first case on the cutting of the terrace and in the second on the marine withdrawal from the terrace. At times of marine retreat, the rapid withdrawal of the water in the first case corresponds to the acceleration of the rate of withdrawal in the second, producing the comparatively flat surface of the terrace; and the still-stand of the first, producing a sea cliff without deposit, corresponds to the slower movement of the second, producing a steeper, deposit- covered slope. The distinction is valuable because it provides criteria for estimating the rate of marine withdrawal and for estimating the width and dip of the submarine slope. Also, the first kind of terrace may indicate continental sinking or the rise of sea level. In discussions of the ages of terraces, marine or terrestrial, it is sometimes important to make clear whether it is the time of the original cutting of a bench, or of the deposition of material on the bench or older surface, or of the withdrawal of the depositing or cutting agent (i. e., the age of the flat surface of the terrace), or of the cutting into the terrace by the beginning of a new cycle of erosion that is referred to as the age of the terrace. In phj'siographic discussions of peneplain remnants or of river terraces, it is usually the last that is meant; in physiographic discussions of marine terraces it may be the first; and in discussions of deposits it is usually the second or third, which, if the deposit is thin, may be approximately the same. River terraces should be discussed as carefully as marine, for broad old valleys indicate still-stand of base level, deposition of terrace materials indicates depression, and cutting into older valleys or deposits indicates uplift. At present, correlations between individual terraces can be made only at short distances. It is clear that readjusting movements were differential in California for a time at least after the mid-Pleistocene deformation, and may even be slightly diverse in different districts today. However, if it be recognized that after most of the local readjustment had been accomplished the major stages in the uplift and later depression of the coast were widespread and essentially contemporaneous, it may in the future be possible to make more distant correlations between such terraces perhaps as the San Diego Mesa and the Burton Mesa, or between some of the river terraces of southern California. 26 San Diego Society of Natural History [Memoirs Conclusion of Remarks on Correlation From the foregoing discussion, it will appear that correlation in the late Tertiary and Quaternary between California formations that are in separate basins or are separated in such a way that they cannot be traced or identified by lithology or other direct means, and correlation between these formations and formations in other parts of the world, can be done in some cases by noting the presence of the important living and extinct species in each formation or the important species that the formations have in common; but in other cases the climatic method may be more useful or more accurate ; and some- times the position of the formations in the marine sedimentary cycle seems to be an assist- ance. The sedimentary record may be complicated somewhat, especially in detail, by submarine diastems, scour, and fill under the control of the profile of equilibrium. At present, correlation of terraces must be done very cautiously. Description of Local Sections The Ventura Basin The later Cenozoic marine sequence of the Ventura basin, when studied in connection with the lower Pleistocene sequence of the Los Angeles basin, provides a key for the unraveling of the later Cenozoic history of California, and for this reason will be discussed somewhat in detail. The Ventura basin contains one of the most interesting, probably the thickest and most complete of the sections of later Tertiary and Quaternary deposits in California. The maximum thicknesses of strata in the Pliocene and Pleistocene ap- proach 16,000 feet and 4,000 feet respectively on the north side of the basin between Santa Paula and Ventura. The principal publications' on the region have been by Eldridge and Arnold, English, Kew, Eaton, Cartright, Waterfall, and Pressler; and another by P. Kerr and H. G. Schenck is in the course of publication. The Ventura basin is a structural syncline or synclinorium heading in an area about 30 miles north-northwest of Los Angeles in the upper end of the Santa Clara Valley of the South and extending in a westerly direction for a distance of about 45 miles to the city of Ventura on the coast, where the widening V of the basin plunges beneath the water. The coast line westward from Ventura to and beyond Santa Barbara, 50 miles or more, may be the extension of the extreme northern rim of the basin. The Channel Islands, lying off the coast to the southward, may or may not be remnants of the sub- merged southern rim. The edges of the basin to the north and to the south are, in general features, anticlinal ; but in some cases they are faulted up or overthrust over the basin. Granites and very old metamorphic rocks in this region are generally classed together by geologists as the basement complex. The basement complex is overlain by a thick section of Cretaceous and Eocene sediments, mostly marine, followed by non-marine Oligocene beds and the younger marine sequence that will now be described. As geol- 1 Eldridge, G. H., and Arnold, R.: "The Santa Clara Valley, Puente Hills, and Los Angeles Oil Districts of Southern California," Bull. 309, U. S. Gcol. .Survey, pp. 1-36, 1907. English, W. A.: "The Fernando Group Near Newhall, California," Univ. Calif. Publ. Geol., Vol. 8, pp. 203-218, 1914. Kew, W. S. W.: "Geology and Oil Resources of a Part of Los Angeles and Ventura Counties, California," Bull. 753, U. S. Geol. Survey, pp. 1-107, 1924. Eaton, J. E.: "Divisions and Duration of the Pleistocene in Southern California." Bull. Amer. Assn. Pet. Geol., Vol. 12, pp. 111-141, 1928. Cartright, L. D., Jr.: "Sedimentation of the Pico Formation in the Ventura Quadrangle, California," Bull. Amer. Assn. Pet. Geol., Vol. 12, pp. 23,5-269, 1928. Waterfall, L. N.; "Contributions to the Paleontology of the Fernando Group, Ventura County, California," Univ. Calif. Publ. Geol., Vol. 18, pp. 71-92, 1929. Pressler, E. D.: "Fernando Group in the Las Posas-South Mountain District, Ventura County, California," Univ. Calif. Publ. Geol., Vol. 18, pp. 325-345, 1929. Volume I ] Pliocene and Pleistocene Mollusca of California 27 < O < 00 < S 3 < >-. « T> '^ H d Z o > >, H X! S TT H OJ »r1 O u ^^ CJ ^ g r o K cS r^f m rL, n. < P, o X :2 u o H CO W U) O Oi n-j o 28 San Diego Society of Natural History [ Memoirs ogists are still not in entire agreement concerning the location of the Miocene-Pliocene boundary, a brief account of the Miocene deposits is inserted here to show what, according to the views expressed in the present paper, preceded and formed the setting for Pliocene deposition. The Miocene marine cycle in the Ventura basin began with the encroachment of the sea over the nearly flat surface of the alluvial outwash deposits of the Sespe formation (Oligocene and partly lower Miocene), which at that time probably resembled very closeh^ the alluvial outwash deposits that are now forming on the nearly flat floor of the San Joaquin basin. The Vaqueros formation, which was then deposited in the western part of the Ventura basin, grades upward from a sandy basal phase representing the littoral zone of mariiie transgi-ession, first into a bufT-colored clay shale and then with practically imperceptible change into the hard black shales interbedded with yellowish calcareous strata that lie at the bottom of the Monterey formation. In the middle Miocene, represented by the Monterey formation, the sea had encroached still farther on the land, depositing sediments in the eastern part of the basin as well as in the western. In the western part, then relatively far from shore, the black shales were followed by typical, whitish, thinly-laminated siliceous shales, which are hard and opalized below, but sometimes light and porous above, often sulphurous and petroliferous. Eastward, however, more sandy material is intermixed with the shales, and the shore phase is again to be found, especially to the southeast. The Santa Margarita formation,^ upper Mio- cene, is known from undoubted fossil evidence only in the northeastern corner of the basin where it was mapped as "Modelo (?)" by Kew. There it consists of soft, fine and coarse, bufT-colored sandstones with interbedded conglomerate lenses; and the oyster-facies fauna that it contains in places suggests that the basin was filling up and giving place near its head to brackish-water or mud-flat conditions. Elsewhere this stage of deposition may be represented by the upper part of the Monterey formation as described above; or it may never have been deposited; or it may have been removed by erosion following the diastrophic readjustment that brought the Miocene cycle to a close. The last phase of a marine cycle is always the least likely to be preserved. A large part of the sequence just described is known locally as the Modelo forma- tion, a formation which appears to include at its type locality north of Fillmore all of the Miocene except the Vaqueros, possibly including even some of the Vaqueros. There seems to be evidence at this locality of at least three minor marine cycles or oscillations. The Vaqueros basal phase exposed in Sespe Creek grades up into a shale which is followed by a return of near-shore conditions indicated by a sandstone series, above which lie a middle shale, an upper sandstone, and an upper shale. In the upper sandstone were found poorly preserved fossils believed to be upper Miocene in age, and because of them and similar forms found in the Santa Monica IVIountains the whole of the Modelo has been assigned to the upper Miocene. It seems more probable, however, that the lower sandstone and middle shale represent the Monterey minor cycle, and that only the upper cycle should be assigned to the upper Miocene or Santa Margarita formation. The lowest shale contains fossils like those of the Temblor formation, middle Miocene, and should therefore be called Temblor or upper Vaqueros. The striking similarity of the whole sequence of lithologic and faunal units found in several regions from the western part of the Ventura basin northward to the southwestern side of the Salinas Valley, middle California, where the Vaqueros and Monterey formations were originally described 1 The term Santa Margarita formation is here used in a general sense, as the name that was earliest applied to the upper Miocene part of the section. San Pablo and other later names are reserved for use when more detailed subdivHsions such as have been made in middle California can be recognized. Volume 1 ] PlIOCENE AND PLEISTOCENE MOLLTJSCA OF CALIFORNIA 29 and not far from the locality at which the Santa Margarita was first described, shows that conditions were more than local and that the older well-known formational names can be applied with perfect propriety in the Ventura basin. As the name Modelo does not appl.y to a natural unit and is not needed, it should be abandoned. In the Ventura basin, as well as in other parts of California and possibly also in Oregon and Washington, the upper Miocene minor cycle of sedimentation is more distinct than the other minor Miocene cycles, for it seems to have been preceded by dia- strophic readjustments causing it to overlap locally on non-marine or pre-Miocene formations. In the northeastern corner of the Ventura basin it overlaps on a non-marine wedge of the Mint Canyon formation. As vertebrates in the Mint Canyon formation indicate that the Mint Canyon is upper Miocene in age', the overlying Santa Margarita of this region must be very high in the Miocene, and the next series of beds younger than the Santa Margarita is almost necessarily Pliocene. Hudson and Craig- found the upper division of the Modelo locally unconformable over the middle division, which is here believed to be the Monterey part of the Modelo. Overlying what appears to be typical siliceous Monterey shale in various parts of the basin where the Santa Margarita formation is not definitely recognized is a brown shale series of somewhat uncertain relationships. In places it seems to have a fossil- iferous basal phase, for very recently a sandy and conglomeratic stratum carrying an abundant molluscan fauna has been discovered. The new locality lies on the slopes above Pico Canyon, stratigraphically far below the Miocene-Pliocene contact as mapped by Kew, and yet it is said that the fossils are of Pliocene age, presumably like those at the well-known Elsmere Canyon locality not far away. Unfortunately, an opportunity to examine this material has not occurred and no opinion can be given of its significance. It may be well to mention, however, that it is very difficult to distinguish the normal shore fauna of the upper Miocene from that of the lower Pliocene, many of the species being distinguished nomenclatorily but not morphologically. Elsewhere this formation of disputed age can be seen to grade upward from the siliceous shales, changing in char- acter by the admixture of more and more detrital material until in the upper part it consists principally of a brittle silty shale. This shale was originally gray but is now stained chocolate-brown along many fine lines of shelly cleavage, so that only the centers of the largest flakes remain gray. Interbedded with this chocolate-brown shale are thin, hard, medium-grained sandstone strata and a few conspicuous but lenticular beds of conglomerate. From the stratigraphic evidence it is strongly suggested that this forma- tion represents the end of the Miocene sedimentary cycle and is the equivalent of the Santa Margarita formation already definitely identified in the basin; but at present, the general trend of opinion favors including it in the lower Pliocene, and it is possible that the Pliocene beds of Elsmere Canyon are a continuation of its basal phase as noted near Pico Canyon. At or near the beginning of the undoubted Pliocene a change of conditions took place. Either the relief of the surrounding territory was accentuated by somewhat more pronounced warping, or it may be merely that a rising of sea level inaugurated the new sedimentary cycle and caused the full-sized waves of the overdeepened basin to attack the gneissic and granitic Iiills of the San Gabriel Range and the other older formations around the edges of the basin, bringing about the deposition here and there of unusually * A very recent summary of the vertebrate fauna of the Mint Canyon formation by John H. Maxon has appeared in Publication No. 404 of the Carnegie Institution of Washington, pp. 77-112, 1930. 2 See Hudson, F. S., and Craig, E. K.: "Geologic Age of the Modelo Formation, California," Bull. Amer. Assn. Pet. Geol., Vol. 13, pp. 509-518, 1929. 30 San Diego Society of Natural History [ Memoirs persistent, heavy conglomerate and coarse yellowish sandstone lenses. Interstratified with the conglomerates and sandstones is a greater volume of buff sandy shale, perhaps the material of the upper Miocene reworked, the buff sandy shale with occasional soft gray or yellowish sandstone lenses grading upward into gray clay shale. The typical gray shale of the Pliocene can be distinguished from the chocolate-brown shale by its softer, more clay-like character, and by the presence in many places of pebble-like, orange, limonitic nodules, often weathered out into rectangular fragments. Fossils appear to be abundant only along the old shore line around the northwestern end of the San Gabriel Range, being best exposed in Elsmere Canyon and east of Fernando Pass. These fossils include a few species that are more characteristic of the Miocene than of the Pliocene, such as Pecten estrellanns (typical variety ?) and the variety cata- lince but not variety cerrosensis, and Ficus (Trophosycon) ocoyana varieties, as well as the echinoid genus Astrodapsis, represented by A. fernandoensis Pack. For this reason, they have sometimes been assigned to the Miocene. Similar assemblages with an admix- ture of Miocene species have been found in other California localities where the basal phase of the Pliocene is fossiliferous, and these other occurrences have likewise been assigned to the Miocene, especially the Jacalitos fauna, lower Pliocene of the San Joaquin basin, which contains in common with the Elsmere Canyon fauna the species noted above and also Pecten healeyi variety lohri, Venus (Chione) elsmerensis (a close relative or variety of V. gnidia), V. (CMone) semris variety feriwndoensis, Forreria magister, Cancellaria tritonidea \ar. fernandoensis, and Claims (ClathrodriUia) coaU7igensis (+ els- merensis), besides numerous non-diagnostic species. Because of the similarity in fauna and stratigraphic position, the correlation between the Jacalitos and the Elsmere Canyon beds is considered well established. In spite of the few more characteristically Miocene species that lived on for a short time into this horizon, the faunal relations are much closer with the overlying middle Pliocene than with the Miocene, the middle Pliocene being distinguished only by the absence of the Astrodapsis, of the Ficus, of Ve7ius (Chione) elsmerensis. Area terminum- bonis, and Forreria magister, by the different varieties of P. estrellanus and P. healeyi, by the appearance of a few species not known in lower horizons such as Area multicostata variety camtdoensis, Pecten bellus varieties, Astrcea gradata, and the brachiopod Tere- bratalia (or Dallinella) occidentalis, and by the abundance of Pecten purpuratus varieties, Pecten deserti varieties, and Ostrea vespertina. Other fossils poorly preserved but prob- ably belonging to the basal phase of the Pliocene in the Ventura basin are found at locality 227 S. D. S. N. H., south of Humphreys Station in the upper end of the Santa Clara Valley, including among other species Ficus ocoyana variety and Pecten healeyi variety lohri. They overlie the Mint Canyon formation. At locality 259 S. D. S. N. H. on the slope of hill 2010' west of Pico Canyon and at locality 229 somewhat nearer Pico Canyon, and also at locality 254 east of the big bend in Sulphur Canyon south of Sulphur Mt., are more, poorly preserved fossils of doubtful significance which are here referred to the basal Pliocene. They occur in locally cemented hard calcareous sandstones and concretions. If the newly discovered locality near Pico Canyon really belongs to the basal Pliocene, then this last series of localities belongs to a fourth zone between the zone here assigned to the middle Pliocene and the zone called basal Pliocene. In that case locality 253 west of Palomas Canyon may represent this horizon also; otherwise it probably belongs to the middle Pliocene zone. 1 So marked on the U. S. Geol. Survey topographic sheet. For the localities mentioned, see the accompanying sketch map or the description of localities in part 2. Volume I Pliocene and Pleistocene Mollltsca of California 31 32 San Diego Society of Natural History [ Memoirs Kew has proposed the name Pico formation for the Pliocene beds exposed in Pico Canyon, expressly including the Elsmere Canyon horizon and also the uppermost fos- siliferous horizon at Pico Canyon which is here considered middle Pliocene in age. Thus the Pico at its type locality originally included the lower and middle Pliocene zones. In the western part of the basin similar beds extend upward without marked lithologic break into the upper Pliocene, and there the name Pico has been applied to the whole sequence. Some writers believe that a formation name should cover only the horizons represented at the type locality and that it should not be extended to the whole of the natural unit to which it belongs, even when the unit is later found to be more completely represented elsewhere. It seems more logical and more practical, however, to take the view that a formation name should apply to the whole of the unit, else there would be an unnatural fragment left over that would be hard to deal with; just as in vertebrate paleontology, if someone should describe and name the leg of a rabbit, it is universally agreed that the name shall apply to the whole of the rabbit. Thus the term Pico forma- tion is here used to include all the marine beds in the Ventura basin that are now con- sidered Pliocene in age. Several well-marked zones are recognizable in the Pico : at the bottom, the Jacalitos zone; in the middle, the San Diego zone; and at the top, the Santa Barbara zone. In some places these faunal zones are recognizable as lithologic units also, and it might be thought desirable to apply to them their respective names as formation names. If so, it seems much better to use the older names of the standard section, since the correlations have already been made beyond reasonable doubt, than to learn a new set of local names. The term Pico cannot be applied to any one of the zones by itself, for at its type locality it includes at least two of them, and if later another zone is recognized between the Jacalitos and the San Diego, it will include three. Also, it is antedated by all the other names. If the various members of the Pico are given formation names, then the Pico, including them all, should be used as a group name. The old group name Fernando is no longer of use, for it covers the whole of the Pliocene marine cycle and the lower Pleistocene marine cycle as well, and has no unity at all. Eaton, in an obscure paper,' has proposed the name Santa Paula formation for the lower part of the Pliocene section exposed in Adams Canyon and vicinity north of the Santa Clara River. This name would probably apply also to the lower Pliocene or Jacalitos zone of Elsmere Canyon; but it is probably unnecessary, for the correlation of the beds at the latter locality with the Jacalitos formation of the San Joaquin basin appears to be sufficiently certain to make the name Jacalitos available, if needed. Mr. Eaton, in a recent interview, expressed the opinion based on foraminiferal evi- dence and detailed field mapping in the Ventura basin and on the literature of other places in California that there is a widespread unconformity of importance between the lower Pliocene and later Pliocene deposits of California, accounting for the absence around the edges of the basins of part of the section represented in the centers of the basins. The evidence for this opinion has not appeared in the study of the molluscan remains. Although it is not unlikely that there may have been differential movements shifting the areas of deposition and possibly bringing higher relief on the land and the deposition of coarser sediments for a time, the evidence seems unsatisfactory that there was any great marine retreat at the time. A temporary halt in the depression of the basin would cause transportation of material across the profile of equilibrium and account for the absence of part of the section nearer the shore. 1 Eaton, J. E.: "Ventura Field Controlled Reservoir," Oil and Gas Journal, Vol. 25, No. 25, p. 72, November 11, 1926. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 33 Immediately above the lower Pliocene zone already described, the conglomerates and sandstones disappear, except in a very few places where lenticular masses mark the course of what appear to be old delta channel ways. The gray clay shale is so homo- geneous in character that in most places it reveals nothing of the structure. In the western part of the basin the section is very thick, continuing with much the same character into the upper Pliocene, the very top of which, the littoral phase, seems to have been removed in most places by the advance of the Pleistocene sea. In the eastern part of the basin the shale in turn grades upward into more and more sandy strata with the return of shore-line conditions, and more persistent sandstones and conglomerates reappear. Near this upper part of the section fossils become very abundant, forming an almost continuous and easily recognizable zone all the way from Fernando Pass to Holser Canyon. It is possible that this zone may be divided into three subzones as follows: (1) shaly facies, at the top of the shale section; (2) normal sandy facies with a typical shore-line fauna, usually overlying the shaly facies; and (3) oyster-bed facies, representing the last stage of marine deposition. The faunas of these three facies must have lived contemporaneously, and hence represent conditions of deposition which in most cases happen to occur in the same succession but cannot be used to distinguish fine divisions in a time scale. The whole zone probably passes upward into successively higher and higher horizons with the gradual retreat of shore-line conditions westward. The most easterly occurrence of the middle Pliocene faunal zone may be at locality 201 S. D. S. N. H. in the upper horizon at Elsmere Canyon. Here the section is very thin, probably near the apex of the marine Pliocene wedge, and the upper and lower littoral zones are separated by only 200 or 300 feet of oil-stained shaly sandstone. The strike in the upper part of Elsmere Canyon appears to be rather regular, about N. 45° E., the beds sloping away from the granite with a dip of 35° or less northwestward. The figures given by English in the publication referred to above are probably misprints or apply to some other part of the region. The fauna at locality 201 is poorly preserved and fragmentary; but it contains several fragments of Pecten estrellanus variety cerro- sensis, and as its stratigraphic position corresponds to that of other occurrences of the middle Pliocene fossiliferous horizon, it is here assigned tentatively to the upper littoral zone. A small Ficus also occurs at this locality; but it is not well enough preserved to show whether it is a typical Ficus, or a Trophosycon that had survived a short time after the sea had begun to retreat, living on there into the middle Pliocene as other individuals of the same species did at San Diego. It is of course possible that this upper horizon in Elsmere Canj'on is just another fossiliferous lens of the better known fossil zone found below, and may not have the significance here attached to it. In that case it would probably be necessary to assume that the upper littoral zone had been washed away before the deposition of the thin layer of overlying alluvial gravels of the Saugus forma- tion. The upper littoral zone is easily recognized on the two flanks of the syncline that forms the ridge over the railroad tunnel south of Newhall. From there it can be traced almost without break westward to Pico Canyon, where it is the upper of the two fossil- iferous Pliocene horizons noted by Kew, and thence along the northeast rim of the flat- bottomed valley (Potrero Valley) northwest of Pico Canyon. It swings around the northwest end of the flat-bottomed valley, where it is cut off by a N.-S. normal fault. It can be picked up again in San Martinez Grande Canyon on the north side of the Santa Clara Valley. On the east side of this canyon there is a fossiliferous outcrop that may belong to a slightly higher horizon, probably not more than 100 feet higher, in which the oyster-bed facies is well developed, as it is also in some localities at a similar horizon 34 San Diego Society of Natural History [Memoirs south of the Santa Clara Valley. The oyster-bed facies outcrops along the bluff east of the canyon as far as the big bend in the canyon where it passes under a shallow syncline and strikes eastward on the southern dip slopes of some of the highest hills, finally ending in the little double anticline of hill 1668 on the U. S. G. S. topographic sheets, east of San Martinez Chiquito Canyon where it is cut off by an E.-W. thrust fault. The normal facies appears again north of the fault on hill 2223 at the head of Holser Canyon, from whence it swings around northward to the top of hill 2018 and eventually crosses the Hasley Canyon road just east of the divide. By walking along the outcrops of the fossiliferous strata and by noting other parallel lithologic units it is possible to demon- strate to a reasonable degree of certainty that all of these localities belong to a single zone of littoral deposits. All the overlying strata are non-marine sands and gravels belonging to the Saugus formation; all below belong to the marine Pliocene. Some of the marine fossil localities in the littoral zone just described have been mapped as Saugus, and some as Pico (middle and lower Pliocene). It is probably in part because of the assignment of some of these occurrences to the Saugus that the name Saugus has been applied, as is now believed erroneously, to marine beds of various ages. From being applied to the middle Pliocene marine beds just described the name was again shifted to the Pleistocene deposits in the western part of the Ventura basin. If the present correlations are correct it is quite obvious that the name Saugus should be used only for non-marine beds such as occur in the vicinity of the town of Saugus, that the Saugus may include the entire non-marine equivalent of the Pliocene marine sedi- mentary cycle and also part of the Pleistocene, but that the name is in no way applicable to the Pleistocene marine beds of Ventura County. The fauna of the shaly facies of the middle Pliocene is usually rather poor, containing only casts of small pelecypods. The normal sandy facies is characterized by Pecten {Pallium) swiftii and varieties, Pecten (Aequipecten) deserti and varieties, Pecten (Janira) bellus and varieties, Ostrea vespertina, Turritella vanvlecki, Dosinia jacalitosana, Pecten (Aequipecten) purpuratus and varieties, Pecten (Lyropecten) estrellanus variety cerro- sensis, Pecten (Patinopecten) healeyi typical variety, Pecten (Janira) stearnsii and varieties. Area multicostata variety camuloensis, Area trilineata variety calcarea, Venus (Chione) securis variety fernandoensis, Cantharus fortis varieties but probably not the typical, Astrwa (Pomaulax) gradata, Fusinusbarbarensis and varieties, Cantharus humerosus , Can- cellaria hemphilli, and others. The first four, including Pecten bellus variety coalingaensis and in addition many non-diagnostic species, are found also in the "Pecten cocdingensis zone" of the San Joaquin basin; and as the two zones correspond in stratigraphic position, it seems quite certain that they can be correlated closely enough for practical purposes. Furthermore, nearly all of the species just listed, including Dosinia jacalitosana (a close relative of D. ponderosa), are found in the type section of the San Diego formation. As there can be little question of the correlation of the San Diego formation with this middle Pliocene zone of the Ventura basin, it is hereby proposed to call it the San Diego zone of the Pico formation. The oyster-bed facies is characteristic of the last marine deposits in a rapidly filling shallow embayment. It is found not far above the normal sandy facies on both sides of the Santa Clara Valley. Its fauna consists usually of a few species that are very common, with here and there a straggler from the normal sandy facies. The common species are Dendraster diegoensis Kew, variety ?, a variety resembling very closely *in its size and shape and in the arrangement of the petals D. oregonensis (W. B. Clark in Dall) but with the anus in the normal position; Pecten (Janira) bellus, especially the distorted variety slevini; and Ostrea vespertina, usually the underdeveloped variety sequens. The fauna Volume 1 1 PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 35 of this facies, including the few normal species such as Cantharus humerosus that straggle into it, does not in any way indicate that there is any material difference in age between this facies, which is merely an environmental facies, and the normal. None of the cold- water species of the upper Pliocene is found in it. As the shore-line moved gradually westward, the littoral zone rose to higher and higher horizons (i. e., higher horizons in a time scale, though if the depositional process involved merely a filling up of the basin, taking place progressively from the shore outward, the later deposits may have been laid down all at the same absolute altitude); and somewhere in the region where the records have been removed by erosion there must have been a transition between the middle and upper Pliocene. In the Ventura and Santa Paula quadrangles, the Pliocene molluscan faunas are very poorly represented. The littoral zone probably had risen into the upper Pliocene before it reached this part of the basin, and much of it may have been removed by the readvance of the sea in the lower Pleistocene. Localities 222 to 224 S. D. S. N. H. are fossiliferous lenses deposited in the midst of the tremendously thick section of the Ventura and Santa Paula quad- rangles, but their fauna is not sufficiently characteristic to make their assignment to the middle Pliocene certain. Probably the locality referred by Waterfall to the "lower Pico" represents this zone. The upper Pliocene is a comparatively cold-water zone containing numerous speci- mens of species that live today between Alaska and Puget Sound. A characteristic and varied fauna is found at locality 218 S. D. S. N. H. in Sulphur Canyon east of South Mt. (not to be confused with the Sulphur Canyon south of Sulphur Mt.). Here are found in abundance Pecten {Patinopecten) caurinus, Peden islandicus and the varieties hindsii and j or dani, Pecten beringianus, Natica (Tectonatica) clausa, Neptunea andersoni variety hawleyi (a close relative of Neptunea lirata), Neptunea venturaensis, and a number of species that occur in Jcold water but also range southward, such as Pecten hastatus, Fusinus barbarensis, and Spirotropis (Antiplanes) perversa with varieties both dextral and sinistral. This fauna has been described by Waterfall as the upper Pico. On the north side of the Santa Clara Valley this same zone forms a continuous strip at the top of the homogeneous gray clay shale just below the Pleistocene contact, and may be traced from the eastern edge of the Santa Paula quadrangle many miles to the west- ward. It may be recognized there by the abundant specimens, mostly fragmentary, of Pecten caurinus, which weather out all over the hillsides and are very noticeable. It contains, however, practically no other recognizable species. Locality 225 S. D. S. N. H. between Timber Canyon and Santa Paula Creek is somewhat below the main part of this zone, in a sandstone and conglomerate lens, and has a more varied fauna, though Pecten caurinus is practically the only diagnostic species. The upper Pliocene has been called by various names, middle or upper Fernando, upper Pico, Santa Barbara horizon, Ventura horizon (in part), etc. In spite of reports to the contrary, the upper Pliocene is not represented by marine beds in Pico Canyon or Fernando Pass; but as explained above, it seems reasonable to extend the term Pico as a formational or group name to include this zone as upper Pico. The name Santa Barbara with its type locality at Packard's Hill, Santa Barbara, is the earliest name applied to this restricted zone. Packard's Hill and its fauna were described by Ai-nold in his San Pedro Memoir,^ and the Santa Barbara horizon was recognized by Smith. - 1 Arnold, Ralph; "Paleontology and Stratigraphy of the Marine Pliocene and Pleistocene of San Pedro, California," Mem. Calif- Acad. Sci., Vol. 3, 1903, especially pp. 50-53. ' Smith, J. P.: "Climatic Relations of the Tertiary and Quaternary Faunas of the California Region." Proc. Calif. Acad. Sci., Ser. 4, Vol. 9. pp. 123-173, 1919, especially pp. 141, 149, 150, 151. 36 San Diego Society of Natural History [ Memoirs Arnold described and listed a fauna from another Santa Barbara locality, which he called Bath-house Beach, thinking at the time that it represented a higher horizon; but later, as pointed out by Waterfall, he listed from the Bath-house Beach locality the four diagnostic species by which he had previously distinguished the Packard's Hill locality, and it is almost certain that the two localities represent the same horizon. The name Ventura horizon proposed by Carson' might also be applicable; but the localities cited by Carson and the small fauna listed represent a mixture of Pliocene and Pleistocene, and the name is not needed. This cold-water upper Pliocene faunal zone will here be referred to as the Santa Barbara zone. Pressler has shown that in the Las Posas region south of South Mountain minor diastrophic readjustments caused the Santa Barbara sea to transgress over folded Oligocene and Miocene formations leaving a thin deposit that now underhes the better represented succeeding zone. The movement was appar- ently not great. The marine beds in the western part of the Ventura basin formerly called "Saugus" overlie the Santa Barbara zone. There is seldom, if ever, an angular unconformity between the two; but the overlying beds are coarser grained and north of the Santa Clara Valley have at the base a very persistent zone of littoral fossils, giving good evidence that they were deposited by a later marine transgression. They contain a fauna prac- tically identical with that of the Pleistocene at San Pedro, in which nearly all of the species are still living. These beds have long been thought to be of Pliocene age because they were involved in the great diastrophic revolution that was formerly said to come at the end of the Pliocene. However, because of the Recent aspect of the fauna, because of the correlation with the San Pedro Pleistocene beds, because of the stratigraphic position above the Santa Barbara zone, which is, as explained later, correlated with the uppermost Pliocene of Europe, and because vertebrate and physiographic evidence in various parts of southwestern United States have shown that the diastrophic revolution took place well along in the Pleistocene, these beds are now considered to be of Pleisto- cene age. Similar beds in the Los Angeles basin embrace a series of zones, and the same may be true of the Ventura basin. The lowest and most extensive zone of both basins was recently named in the Ventura basin the Las Posas formation by Pressler.- It contains a warm-water fauna, and, as explained later, corresponds to warm-water beds that underlie the equivalent of what Arnold called Pliocene at Deadman Island in the San Pedro region of the Los Angeles basin. Higher horizons have been recognized near the city of Ventura, and future work may enable paleontologists to differentiate higher zones corresponding to the cold-water "Pliocene" of Deadman Island and to the cool and possibly also warm water horizons equivalent in the San Pedro region to what Arnold called the lower San Pedro series. It is not to be supposed that the minor changes in these faunas giving some an aspect slightly more characteristic of cool waters and others an aspect slightly more characteristic of warm waters can be traced for any great dis- tances, for the changes are probably due to local shifting of currents and local changing of depths; but the general similarity of conditions in the Ventura basin to those at San Pedro, where the major changes of temperature are unquestionably of importance, is apparent. It has already been pointed out above that inasmuch as the name Saugus was originally applied near the town of Saugus to non-marine deposits that range from the middle or older Pliocene through the Pleistocene, it should not be applied to the marine 1 Carson, C. M.: "Pliocene Faunal Zones in Southern Culifornia," Pan-American Geologist. Vol. 43. pp. 269. 270, 192.). 2 Ov- cit. Volume I ) PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 37 Pleistocene in the western part of the Ventura basin, the two occurrences being of different origin and in large part of different age. The name Ventura horizon given by Carson is vaguely defined, without definite type locality, and its mixed fauna and original corre- lation below the Santa Barbara zone rule it out of consideration here. It seems desirable to have a single name for the series of marine strata overljdng the Santa Barbara zone, and the term lower San Pedro series proposed by Arnold, although the lower part of the section was not originally included, seems to be the most appropriate. Tieje, after Kew, proposed to alter "lower San Pedro series" to "San Pedro formation," excluding the upper Pleistocene Palos Verdes (formerly called upper San Pedro series), which was deposited after the great Pleistocene diastrophic revolution. This course seems justifiable, for the beds above the Santa Barbara zone that are involved in the diastrophic revolution form a natural unit, a sedimentary cycle like the Pliocene sedimentary cycle. In the San Pedro formation (or group), then, can be recognized the lower warm-water or Las Posas zone, the middle cold-water Deadman Island "Pliocene," which might be called the Timms Point zone since Deadman Island no longer exists, and the upper zone of cool and possibly also warm-water horizons which is the typical San Pedro zone. Eaton has given the name Hall Canyon formation to what he believed to be the uppermost member of the sequence in the Ventura basin; but in his description he apparently included some of the reddish upper Pleistocene non-marine terrace or fanglomerate formation, which is much better exposed on the hills west of Timber Canyon where it overlies unconformably the Pliocene-Pleistocene marine series. Dr. Schenck has visited the locality and states that it is not quite certain to which formation the beds photographed by Eaton belong. After the deposition of the San Pedro formation or group (the lower San Pedro series) there occurred what appears to be the greatest diastrophic revolution that affected the region since the close of the Jurassic. All of the formations were involved in the folding, and in some places even lower Pleistocene strata were tilted at high angles or overturned. Faulting accompanied the folding, especially thrust faulting during the orogenic disturbances. The major compressive movements seem to have been confined to a comparatively limited period, general opinions to the contrary notwithstanding, and movements since that time have been mostly of the nature of readjustments, possibly isostatic, involving differential elevations or depressions along normal faults and broad regional warpings, but seldom important folding or thrusting. Erosion acted upon the deformed beds during and after the time of the deformation, reducing all but the older hard formations to a surface of moderate relief. This old surface is marked by high-level terraces and deposits of older alluvium or fanglomerate that were formed at the bases of the upthrust mountains. One of the best of these remnants is a deposit of reddish fanglomerate occurring on the tops of the ridges and bevelling the edges of the upturned marine beds west of Timber Canyon on the north side of the Santa Clara Valley. This deposit was formed at the base of Santa Paula Peak, a mountain composed of abnormally hard Eocene strata with a present altitude of almost 5000 feet, that was folded and upthrust during the mid-Pleistocene diastro- phism. As the fanglomerate surface passes undisturbed across the trace of the fault, it is evident that the movement along the fault had ceased before the deposition of the fanglomerate. A similar relationship has been reported along the southwestern side of the northwestern end of the San Gabriel Mountains, showing that the great pair of San Gabriel faults also became extinct before the deposition of the older terraces. Other remnants, probably of this same old surface, in the upper end of the Santa Clara Valley, 28 San Diego Society of Natural History ( Memoirs that were mentioned by Lawson^ and' are now clearly to be seen from the Ridge Route highway north of Saugus, do not seem to have been disturbed by the continuations of the San Gabriel and other faults that pass among them. On the eastern end of South Mountain across the Santa Clara Valley and across the Santa Clara Valley fault from Timber Canyon are also remnants of an old surface with a slope that suggests that it was once the opposite slope of the valley at the time of the deposition of the Timber Canyon fanglomerate, no movement having taken place along the intervening fault since then. The tops of the ridges in the broad belt of Pliocene and Pleistocene sediments north of the Santa Clara Valley and west of Santa Paula Creek are roughly conformable, suggesting that the ridges once formed part of a surface sloping downward from the late mature top of Sulphur Mountain across the Sulphur Mountain fault ; but the rocks being very soft, the remnants of this surface have been much worn down below their original level. All of these occurrences taken together seem to outline in a general way an old land surface that had been subjected to considerable erosion since the deformation of the region and that was later uplifted essentially undisturbed and cut into by streams with a lower base level. For this surface the name Timber Canyon surface is proposed because one of its most clearly preserved remnants is the surface of the Timber Canyon fan- glomerate. The land surface just described probably corresponds to one or more of the marine terraces recognized along the coast. As the uplift of the district continued, several terraces were formed. Of particular note is the terrace that runs along the coast for many miles east and w^est of Santa Barbara and is followed by the highway and the railroad. It varies from a few feet up to 50 feet at the outer edge where it stands as a cliff above the ocean and rises to about 250 feet at the back. In the Santa Maria district, on the coast just around Point Conception to the northward, a similar terrace carves away the edge of a higher and much larger terrace known as the Burton Mesa, which, though obviously older than the Santa Barbara terrace, is probably younger than the Timber Canyon fanglomerate. The Burton Mesa has an elevation of about 300 feet at its lower edge, rising gradually to 500 feet in back where it gives way to a steeper slope which climbs to an altitude of 1000 feet or more. From the 1000-foot mark downward it is capped by a thin sand and conglomerate formation, stained reddish-brown and locally cemented by limonite. Pholad borings in pebbles and in the surface of the underlying truncated Monterey shales show that the capping formation is marine throughout. A probable explanation of this sloping terrace is that the district was forced downward by the deformation and was submerged up to present altitudes of 1200 feet or more, afterwards recovering gradually, the sea slipping away from the present hillside slowly and from the parts that now form the terraces somewhat more rapidly. With a broad, shallow submarine shelf extending probably far beyond the present shore line, perhaps like the shelf at Atlantic City, New Jersey, the force of the waves would all be expended in cutting down the bottom and would have no opportunity to cut back notches in the shore. Only thus can the marine capping formation, continuous over the slopes from terrace to terrace, be satisfactorily explained. During the time of uplift, erosion, and terrace-forming, tremendous masses of the soft unconsolidated Pliocene and Pleistocene beds must have been removed. The mag- nitude of the work done was noticed by Eaton, who was led by it to assign an unusually great age to the early Pleistocene. From the correlations outlined below, it seems evident that Eaton did not allow sufficiently for the nature of the sediments nor for the fact that ' Univ. Calif. Publ. Geol.. Vol. 1, p. 1.57, 1S93. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 39 a local sand and mud pile, even though it be 5000 feet high, can be removed much more quickly than a uniform layer of that thickness extending over a wide area. It might be remarked that the old surface of Sulphur Mountain underlain by hard Miocene shales must have been exposed during most of the erosion interval, and yet it has been cut into around the edges only a few hundreds of feet. The regional elevation of the land was continued until the land all stood higher than at present. Rivers cut deep channels below their present levels, and these channels have had to be filled up subsequently with alluvium when the sea level returned to its present position. It even appears that for a brief time the sea level rose again to a point slightly higher than at present and that the alluvium deposited at that time was later cut into by the rivers when their base levels finally took their present positions. The yoimger fanglomerate of Timber Canyon has not yet been cut into, whereas that in the next canyon to the west has. Many of the other side canyons have very young, well- marked alluvium terraces (some of them as much as 50 feet high), and even the Santa Clara River itself is bordered by remnants of a very young terrace. The sea is now vigorously cutting away the Santa Barbara marine terrace, and it seems probable that if there ever was a very young marine terrace corresponding to the very young alluvial terraces of the river valleys, it may have been entirely removed by the waves. The fauna of the Santa Barbara marine terrace is represented in the collections from localities 40, 74, and 78 S. D. S. N. H., and indicates that the terrace is very late Pleis- tocene in age and the temperature conditions about the same as at present. The not-so- warm aspect of this fauna throws doubt on the exact correlation of this terrace with the very similar Palos Verdes terrace at San Pedro and the La Jolla or Nester terrace at San Diego. It is probable, however, that it is not very different in age, and the more northern latitude, emphasized by a different configuration of the shore line, may account for its cooler facies. It is not unlikely that at the time of the formation of this terrace the Channel Islands, forming the southern rim of the Ventura basin, made a more con- tinuous barrier, shutting off the warmer waters of the south and marking the limit of the range of many southern species. The Los Angeles Basin Most of the detailed information about the Pliocene of the Los Angeles basin is in the files of oil companies or in the form of confidential reports on foraminifera, most of which were not available during the preparation of this summary. The following account, therefore, must be made brief and rather general. As in the Ventura basin, the Pliocene beds were deposited in the form of an overlap on the Miocene. In the Puente Hills' near the edge of the basin, heavy sandstones and conglomerates, especially in the lower part of the section, are indicative of shore-line conditions in an advancing sea. Farther out in the basin, however, the sediments are all finer grained, grading downward into the Miocene siliceous shales; and it is quite likely that there the deposition was continuous from the Miocene into the Pliocene. It is probable that the very base of the Pliocene occurs only in the center of the area of deposition, and that the sandstones and conglomerates in the Puente Hills were deposited, like the earliest Pliocene sediments of the San Diego embayment, sometime after the beginning of the Pliocene. The shore-line occurrences of the Puente Hills are not suffi- ciently well known faunally to show whether the Jacalitos zone is represented there or 1 English, W. A.: "Geology and Oil Resources of the Puente Hills Region, Southern California." Bull. 768. U. S. Geol. Survey, especially pp. 39-44, 1926. 40 San Diego Society of Natural History [ Memoirs not, though this lower Pliocene zone is probably represented in the center and western part of the basin. The Pliocene strata in Temescal Canyon north of Santa Monica reported by Arnold' occupy a similar position, indicating overlap of the Pliocene onto the Miocene near the edge of the basin. The fauna there, though small, is characteristic of the San Diego zone as known both in its type locality and in the Ventura basin. Abun- dant Peden healeyi and the brachiopod Terebratalia (or Dallinella) occidentalis Dall are good indices. Geologists and paleontologists have for the last few years been in the habit of calling the formation to which these strata belong Pico; but there is reason to believe that San Diego formation may be a better term, for the name is older and better characterized. The zone should at least be called the San Diego zone. In the city of Los Angeles is a series of Pliocene strata with its base at the Miocene contact near the old Los Angeles oil field. Higher and higher horizons of the section out- crop southward until the uppermost is reached near the center of the city. Diagnostic fossils have not been reported from the base of the section, but Arnold- has given a list of species collected at the time of the digging of the Third Street tunnel. In this list "Pecten ashleyi," now known as Peden cerrosensis, is indicative of the San Diego horizon, but Peden opuntia, Ranella oregonensis var. angelensis, and Buccinum sp. are more characteristic of the Santa Barbara horizon. In other words, the fauna represents the upper part of the Pliocene in which nearly all of the species of the San Diego horizon have given place to the colder-water forms of the next stage. A similar but much larger fauna collected from excavations for an office building on Fourth Street between Broad- way and Hill was described by Moody. ^ In Moody's list the principal survivor from the San Diego zone that is usually characteristic of that zone is Peden healeyi; but this species is classed as uncommon, and Peden caurinus and others are more characteristic of the Santa Barbara beds. Hence these two occurrences should be placed near the bottom of the Santa Barbara zone. The marine Pleistocene does not directly overlie this section. The most important work on the Pleistocene of the Los Angeles basin is Arnold's San Pedro Memoir.^ In it are carefully described and illustrated three of the most important zones of the middle and upper Pleistocene, termed by him the Deadman Island Pliocene, the lower San Pedro series, and the upper San Pedro series. Arnold thought the number of extinct species in the Deadman Island "Pliocene" sufficient to warrant assigning it to an older period; but since that time nearly all of Arnold's sup- posedly extinct species have been recognized in the living fauna, and very recent work in the San Pedro region has brought to light a rather thick underlying series of strata bearing a warm-water Pleistocene fauna^ that is correlated, as explained below, with the Las Posas zone, formerly called basal "Saugus," of Ventura County. Thus we have in the lower Pleistocene the Las Posas zone, fairly thick and with a fairly warm-water fauna, the cold-water Deadman Island "Pliocene," or Timms Point zone as it will here be called, and the cool-water lower San Pedro series, or typical San Pedro zone, separated by very local unconformities; and then in the upper Pleistocene after the Coast Range mountain-building revolution and a period of erosion, the upper San Pedro series with • Arnold, R.: Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907. ! Arnold, R.: loc. cit., and Bull. 309, U. S. Geol. Survey, p. 152 (same list), 1907. > Moody, C. L.: "Fauna of the Fernando of Los Angeles," Univ. Calif. Publ. Geol., Vol. 10, pp. 39-G2, 191G. < Arnold, R.: "The Paleontology and Stratigraphy of the Marine Pliocene and Pleistocene of San Pedro, California," Mem. Calif. Acad. Sci., Vol. 3, 420 pp., 27 ppl., 1903. * Dr. Woodring of the California Institute of Technology described this warm-water zone a year ago at the meeting of the Cordilleran Section of the Geological Society of America. Volume I ) PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 41 another warm- water fauna. Tieje,' after Kew, has proposed to call the lower San Pedro series the San Pedro formation and the upper San Pedro series the Palos Verdes forma- tion. Tieje has also proposed a name, Centinela gravels, for beds overlying what he thought to be the Palos Verdes in the Baldwin Hills and carrying a still warmer fauna. The section described by Tieje in the Baldwin Hills appears to be more complete than that exposed at San Pedro not far away. Two cold-water zones are described, each of considerable thickness, overlain each by a warm-water zone, all of the zones being later deformed, truncated, and overlain by the ancient Los Angeles River gravels. In the light of present correlations it seems probable that the lower cold-water beds repre- sent the Santa Barbara zone; the lower warm-water beds, the Las Posas zone; the upper cold-water beds, the Deadman Island "Pliocene," or Timms Point zone; and possibly the beds called "Palos Verdes" in the Baldwin Hills, the lower San Pedro series of Arnold, or the typical San Pedro zone. As explained below, the typical San Pedro zone is corre- lated with the beginning of an interglacial age and although its fauna may have repre- sented cool-water conditions at the start it would not be surprising to find the cooler water sub-zone giving place to a warmer water sub-zone. According to Tieje's descrip- tion, his "Palos Verdes" of the Baldwin Hills seems to underlie the main unconformity. Perhaps his Centinela gravels represent the true Palos Verdes. Even if the whole sequence had not been found by Tieje in the Baldwin Hills, or if there should be some mistake in the identification of his zones, there would still be suffi- cient evidence to prove the presence of two cold-water zones separated by a distinctly warm-water zone and overlain by a zone of mild, perhaps in part of distinctly warm, tem- perature. In the Ventura basin the cold-water Santa Barbara zone is underlain by the warm-water Pliocene San Diego zone and overlain by the warm-water Pleistocene Las Posas zone. In the San Pedro district of the Los Angeles basin the cold-water Timms Point zone is underlain by a warm-water Pleistocene zone and overlain by another Pleistocene zone of apparently intermediate temperatures now to be called the typical San Pedro zone. As the two cold-water zones are of very similar faunal character, it is natural to consider correlating them, and, indeed, such a correlation is now on the point of being generally accepted; but the relations of these two cold-water zones to the warm- water zones above and below them show that a correlation between them is impossible. It would necessitate the correlation also of the lower warm-water Pleistocene zone of the San Pedro district with the San Diego Pliocene zone of the Ventura basin, unless it be argued that in the Ventura basin there are one or more zones missing between the Santa Barbara and the San Diego. On the north side of the Santa Clara Valley certainly and probably also in the city of Los Angeles the gradational nature of the lithologic and faunal transitions from the San Diego Pliocene to what is here called the Santa Barbara zone shows that the sequence is unbroken and that no important zone is missing. The San Diego Pliocene is so different faunally from each and all of the Pleistocene warm- water zones that a correlation between the San Diego Pliocene, whether of the San Diego, Los Angeles, or Ventura basins, with any Pleistocene faunal zone is entirely out of the question. Hence the discovery that the cold-water Timms Point zone overlies a warm-water Pleistocene zone, which could not through any possible mistake be the San Diego zone, proves that there are at least two different cold-water zones. The warm- water Pleistocene zone must itself be younger than the Santa Barbara zone of the Santa Clara Valley and the city of Los Angeles (for it cannot underlie it or be correlated with it) ; and if the Timms Point zone overlies this warm-water zone, it must also be ^ Tieje, A. J.: "The Pliocene and Pleistocene History of the Baldwin Hills, Los Angeles County, California," Bull. Amer. Assn. Pet. Geol., Vol. 10, pp. 502-512, 1926. 42 San Diego Society of Natural History [Memoirs younger than the Santa Barbara zone. The possibility that the beds here referred to as the Santa Barbara zone are not properly correlated with the Santa Barbara type section is not of importance for this particular consideration. The lowest warm-water Pleistocene zone of the San Pedro region, being younger than the Santa Barbara zone of the Los Angeles and Ventura basins, is therefore the probable equivalent of the Las Posas zone of the Ventura basin, which is a warm-water Pleistocene zone of similar characteristics and at its type locality overlies the Santa Barbara zone. The zone at San Pedro must represent either the same interglacial age or a younger one. As the correlation with other regions shows that there is room for no larger number of major temperature alternations, this warm-water zone of the lower Pleistocene in the Los Angeles basin is here correlated with the Las Posas zone of the Ventura basin. The two sections have practically indistinguishable faunas. Each is the oldest known Pleistocene warm-water zone in its basin. Each is made up of a series of coarse and fine sediments many times, probably more than ten times, as thick as any other known Pleistocene zone in either basin, indicating a time of vigorous deposition. Failure to correlate the two would imply that there were two ages when conditions were suitable for vigorous deposition but that each age is largely or entirely unrepresented in the known deposits of one of the basins. It is improbable that under conditions favoring the deposition of several thousand feet of sediments in one basin there would be no similar deposits in a nearby basin which is shown by its other deposits to have been susceptible at the time to the deposition and subsequent preservation of sediments. The only other Pleistocene zone of the Los Angeles basin with which anyone might consider correlating the thick Ventura section is the typical San Pedro zone, which in comparison is insignificant in thickness and extent. Such a correlation is improbable, aside from the difficulty just discussed, that the lower warm-water zones would not match. The Las Posas zone is, then, younger than the Santa Barbara zone and older than the Tinims Point zone. The Santa Barbara zone (upper Pliocene) can usually be distinguished by the presence of Peden bellus and Peden opuntia and possibly other species, which are of fairly regular occurrence in the Santa Barbara zone but are lacking or of rare or very doubtful occurrence in the Timms Point zone. A summary of the lower Pleistocene marine record in the outer part of the Los Angeles basin may be given as follows : (1) Las Posas zone, warm-water calcareous beds overlying the Santa Barbara zone in the Baldwin Hills area only, underlying the Timms Point zone on Second Street near Pacific Avenue, San Pedro, and most characteristically exposed in the Lomitas Quarry and in another quarry locally known among Los Angeles paleontologists as Hilltop Quarry, farther inland and higher up on the southeastern end of San Pedro Hill. R. D. Reed has worked out the sequence in San Pedro. Dr. Woodring of the California Insti- tute of Technology has studied and described the localities mentioned, expressing his conclusions in the paper referred to above. The correlation with the Las Posas zone of the Ventura basin can be considered practically certain. (2) Timms Point zone, a cold-water zone, predominantly clayey in lithology, for- merly exposed on Deadman Island in San Pedro harbor, now typically exposed at Timms Point, San Pedro, where it overhes unconformably lower Pliocene or upper Miocene shales, and also exposed on Second Street, San Pedro, where it overlies the Las Posas zone uncon- formably. (3) Typical San Pedro zone, a moderately cool-water zone, possibly grading up into a warm-water sub-zone, formerly exposed on Deadman Island, but now known only Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 43 from a few remnants at the foot of Second Street, San Pedro, where it is separated in apparently conformable sequence from the Timms Point zone by a section of cross- bedded unfossiliferous sands, in lithology not unlike some cross-bedded Pleistocene sands exposed along the highway in Grimes Canyon, Ventura County. The "Palos Verdes" of the Baldwin Hills may or may not belong to this zone. The "upper San Pedro" of Los Cerritos, now better known as Signal Hill, one of Arnold's original localities, recently described by Tieje in a paper given before the Pacific Coast Section of the American Association of Petroleum Geologists, probably belongs either to this or to the Las Posas zone. This last locality was originally assigned to the upper San Pedro (true Palos Verdes), because it was then thought that there was only one warm-water horizon in the Pleistocene. However, the beds are highly deformed, and Tieje suspected from the fauna that thej' might be older. Recent workers in the San Pedro region have been applj'ing the term zone to divisions of a distinctly lesser order of magnitude than the divisions outlined above. Pleistocene deposits have been divided into "zones" represented by strata a few feet or sometimes only a few inches in thickness. Perhaps it would be more convenient and more nearly in accord with general usages to call most of these fine divisions faunules and a few of them which could be recognized in two or three different outcrops and which would appear to indicate significant, though minor, changes in conditions sub-zones. Detailed studies such as are being carried on are sometimes useful in bringing out data on the equilibria of individual faunas and may occasionally indicate the trend of the major changes that were taking place. However, it must be considered that near-shore deposits such as are found throughout the Pleistocene were at the time of deposition subject to the fill and scour of ocean currents and to the local change of depth and other conditions so that none but the major reversals of temperature should be expected to persist in recognizable form for any considerable distances and minor variations in temperature should be expected to be of little use in making correlations. In a very recent article,' Crickmay has described in this manner the stratigraphic succession at the well-known Deadman Island, an island that was formerly located in San Pedro harbor but has now been entirely removed by steam shovels. It is highly desirable that all available information about such a locality, made familiar to all California paleontologists by Arnold's early work, should be put on record, and the collections upon which this article is based and the detailed description of the deposits will in themselves be of sufficient value to repay the considerable amount of work that they must have required. However, it is difficult to agree either with the importance attributed to the fine faunal "zones" or with the interpretations of the faunal evidence. Perhaps if the fine divisions were called faunules there would be no temptation to assign them undue significance. It is argued, in particular, that in the Deadman Island "Pli- ocene," here called the Timms Point zone and correlated because of its cold-water fauna with a glacial age, there is not merely a single faunal zone but several "zones," some of which carry faunas indicating warm temperatures. If this were true there would already be known at San Pedro more major alternations in temperature than could be correlated with the known glacial and interglacial ages of other regions, and the presumption would be that still many more have not been recorded. If true, it would invalidate most, if not all, of the correlations of glacial ages that have so far been made. But the fact is overlooked that in such deposits as are found at San Pedro fine layers measured in inches are the playthings of storms and ocean currents, at most the products of local 1 Crickmay, C. H.: "The Anomalous Stratigraphy of Deadman's Island, California," Journ. Geol., Vol. 37, pp. 617-63S, 1929. 44 San Diego Society of Natural History [Memoirs oscillations in the profile of equilibrium. Except when there are very long gaps in the depositional record, long diastems or intervals of subaerial erosion, the climate cannot change from warm to cold during the deposition of a foot or two of even moderately fine sediments. Furthermore, the chief reason in this particular case why the evidence for major temperature changes between faunules breaks down is that it is based on apparently erroneous interpretations of the thermal indications of various species. The argument hinges on the presence in certain faunules of so-called warm-water species, the accompanying cold-water species being explained away rather unconvincingly as washed in from deeper water or redeposited. But not a single species from one of these faunules of the Timms Point zone that was cited as indicative of warm temperatures is confined in its living range to southern waters. All range today north of San Pedro and some of them go far north. Turritella cooperi, Peden stearnsii variety diegensis, Mangelia hex- agona (cited as Cyiharella branneri), and Trivia ritteri are known from Monterey Bay; Fusinus barbarensis and Chama pellucida are known from Oregon; and Epitonium indianorum was originally reported from the coast of Washington and is known abundantly in Alaska. Cardita barbarensis is only questionably distinct from other species of Cardita that are as a group common in Canadian and Alaskan waters. Turritella jewetti alone among the species of the Timms Point zone that are cited as southern in distribution goes no farther north than Santa Barbara, and it will be noticed that it is listed in that zone only as Turritella cf.jeuietti and is said to be rare. Moreover, if one or two species that now range only in southern waters had been found in a pre- dominantly cold-water fauna, it would not be surprising or particularly significant, for it must be recognized that the distribution of species is not whollj'^ dependent upon temperature. The competition of other species probably has fully as much to do with it, and in some cases the distribution of temperatures throughout the year and a host of other minor factors have influence. In the past, some species have had a much more extended range than they have now, and some have had an entirely different range. Crepidula princeps, for instance, is abundant in some warm-water faunas in the Pliocene and Pleistocene; but its descendant, C. grandis, ranges only from the Arctic Ocean to Sitka, Alaska. Similarly, a few species of previously wide range may now be confined to warm waters. Therefore it must be concluded that no significant evidence has yet been submitted to show that there are any more major divisions in the lower Pleistocene of San Pedro than are outlined above, though it is possible that in the Timms Point zone of San Pedro there might be one or more less distinctly cold-water sub-zones. The areas that remained land during the deposition of the Pliocene and lower Pleistocene sediments were reduced by erosion to a surface of low relief. This surface has been recognized as the Perris peneplain by English, who correlates with it the uplifted surface of the Bear Valley region of the San Bernardino Mountains.^ This pre-deforma- tion surface was subsequently dismembered, and all but the portions that were developed over areas of the older hard rocks have been obliterated. The remnants of this surface are usually not hard to distinguish from the post-deformation surfaces. During the deposition of the lower Pleistocene sequence slight diastrophic move- ments had taken place, for the various zones are separated by unconformities; but these unconformities are chiefly erosional, involving only small angular discordances in dip. As the uppermost of these zones, the typical San Pedro zone, is involved in the major part of the folding, it is evident that the main deformation did not come until after the deposition of that zone. Furthermore, the compressive deformation that caused the 1 EngliBh, op. cit.j p. 64. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 45 folding of the beds had ceased before the cutting of the marine terraces, mentioned beloM', for the terraces are not disturbed by the folding that affects the beds underlying them. Apparently the compressive forces resulted in the depression of San Pedro Hill, which afterwards, in the succeeding time of readjustment, rose again, as shown by a series of a dozen or more well-marked marine terraces that extend almost to the top of the hill. Lawson has described most graphically these later Pleistocene marine terraces.' The lowest of these terraces is covered by a thin, richly fossiliferous marine deposit overlying horizontally the truncated edges of the pre-deformation series. This deposit, called the upper San Pedro series by Arnold, has been renamed the Palos Verdes formation. Its fauna is of a strikingly warm-water facies. Other parts of the basin were affected differently during the readjustment after the deformation. Only along or near the coast are marine terraces recognizable, although an elevation of sea level to the top of San Pedro Hill would now cause the flooding of a vast area inland. The upthrusting of the great mountain blocks during the period of compression seems to have brought the inland areas as a whole to so high a level that the following reaction did not tend to uplift them further. Some of the intervening blocks had been downpressed and deeply covered with alluvium. It is unlikely, how- ever, that the famous Rancho La Brea vertebrate accumulations belong to this time of the alluvium filling of downpressed blocks. They were situated on a block that was uplifted at the time, for the underlying beds were truncated before the asphalt deposits could begin to accumulate. It is much more likely that the Rancho La Brea alluvium and tar beds belong to the later time of alluvial accumulation represented by the older alluvial terraces. Afterwards the region as a whole rose again and the alluvium was partly scoured out. We may know only the base of what was once a much thicker brea deposit. The relative ages of the Rancho La Brea vertebrates and of the Palos Verdes invertebrates are not directly observable, but the antiquity of the vertebrate fauna and the youthful physiography of the Palos Verdes terrace suggest that the latter is somewhat younger. After the deposition of the Palos Verdes terrace material, the continent must have risen or the sea level subsided, causing the ocean to begin its task of cutting away most of the broad shelf that then extended outward from San Pedro. As explained later, the sea level probably stood lower on the land then than now and only in com- paratively recent times returned to cut the present sea cliff in the edge of the overdeep- ened basin. The raised beach at Deadman Island mentioned by Arnold might indicate a slight uplift, perhaps local, or a lowering of sea level in very recent times. The San Diego Basin The geology and physiography of the San Diego region are described by Ellis and Lee,^ and a later account is given by Hanna;^ but in both of these papers the Pliocene deposits are very briefly treated. In an early paper, Dall discussed the "San Diego beds" and listed a fauna which he tentatively identified as Pliocene.* In 1902 the name San Diego formation was definitely applied by Arnold.* The second volume of the 1 Lawson, A. C: Univ. Calif. Publ. Geol., Vol. 1. pp. 122-128, 1893. 2 Ellis, A. J., and Lee, C. H.i "Geology and Ground Waters of the Western Part of San Diego County, California," Water Supply Paper 446, U. S. Geol. Survey, 321 pp., maps, illustrations, etc., 1919. 3 Hanna, Marcus: "Geology of the La Jolla Quadrangle, California," Univ. Calif. Publ. Geol., Vol. 16, pp. 187-246, illustrations, map, 1926. * Dall, W. H.: "Notes on Some Tertiary Fossils from the California Coast, with a list of the species obtained from a well at San Diego, California," etc., Proc. Calif. Acad. Sci., Vol. 5, pp. 296-299, 1874. s Arnold, R.: Journ. Geol., Vol. 10, p. 130, 1902. 46 San Diego Society of Natural History [ Memoirs Memoirs of the San Diego Society of Natural History, now in process of preparation by L. G. Hertlein and IT. S. Grant, will describe fully the occurrence and fauna of the San Diego Pliocene. It appears that the part of the San Diego basin that is now exposed to view was depressed in the Pliocene either not so rapidly or not so early as the Ventura basin, and that consequently the marine transgression did not encroach upon the downwarped peneplain surface of the Eocene sediments until about the beginning of middle Pliocene time. Also the sediments had not become very thick before the sea retreated again beyond the present shore line, or else the younger parts of the deposits have been removed. Thus the San Diego formation, and it appears to be the only one of the named California formations of which this statement is true, is practically confined to the middle Pliocene. It probably corresponds roughly to the time of maximum marine invasion in other parts of southern California and Lower California, the sequence of events being much the same as in the shallower parts of the Ventura and Los Angeles basins. In the San Diego region the cycle began with marine transgression marked by a thin basal conglomerate overlapping on the slightly tilted Eocene. Fossils in the lower part indicate a rather warm climate, even including specimens of Ficus, subgenus Trophosycon, that evidently persisted longer in the San Diego region than they did farther north; but in the upper part cooler-water species began to appear. The marine retreat probably took place before the arrival of the extremely cold conditions of the Santa Barbara zone. Practically all of the characteristic species of the San Diego forma- tion are known also from the middle Pliocene of the Ventura basin: Cancellaria hemphilli, Terebra elata variety martini, Area trilineata typical variety and variety calcarea, Venus (Chione) securis variety fernandoensis, Pecten purpuratus varieties, Pecten healeyi, Pectcn estrellanus variety cerrosensis, Pecten swiftii varieties, and the brachiopod Terebratalia occidentalis, besides many other species less characteristic of the middle Pliocene. There can be little reasonable doubt about the correlation of these middle Pliocene faunas, and it is for this reason that it is proposed to utilize the name San Diego in other basins. Further information about the history of the San Diego formation and the condi- tions under which it was deposited can be made out from a study of physiography. The San Diego Mesa is the most conspicuous topographic feature of the region. Its broad, nearly flat surface, capped by a thin residual conglomerate, extends in a broad belt along the coast north and south of San Diego, nearly ten miles wide in places and many times longer. Although it has been uplifted and slightly tilted so that it is about 450 feet high in the northeast and 300 to 350 feet in the south and west, the rivers which cut across it have done no more than erode comparatively narrow canyons and have left most of the surface intact. The thin conglomeratic surface of the mesa overhes unconformably Eocene beds north of the San Diego River valley where the mesa has been called the Lindavista terrace, and southward it overlies unconformably the San Diego formation where the mesa has been called the Otay terrace ; but the surface of the mesa is a single surface and should have but one name. At the edge of the San Diego Mesa, about two miles northeast of the northeasternmost outcrop of the San Diego formation, is the beginning of a higher surface known as the Poway terrace. It begins there at an elevation of about 700 feet and rises both eastward and northward, reaching 800 feet a mile and a half eastward and the same elevation five miles northward. It rises to gi'eater elevations beyond. The Poway terrace is maturely dissected, being represented only by the approximately alligned crests of ridges. There may be higher surfaces also. Volume I ] Pliocene and Pleistocene Mollitsca of California 47 J o cc bC & 0^ o (3 z C <: c3 H CC ►J g t» c" o _o z -^ H 'x o o 0^ Z H ^ o o Q p z §"s M <; S g o 02 o C Ph +s Oj H F<4 .22 Q Q O w H Ph c a> < z 2 2; o3 a; < <; s§: 1— 1 z o o Q z < Sti CO z .2"S °5 o o z s o z 5 3 w w Eh -1 z O O o Oj a _c CK +J s cc <; CD « O o cS < ^ ^ Q H ij >, <: cS a pL, 1 ! A ,vv^ lVi%'-.\^ ",S? i-U\'>l \, K\! :\^ >R ^ um^f — "a Si - £ « .2 ^ X |H S a Q o 0) c VI J3 ii: > Qj O rt OS " o ■X -a oi in _ X 2 S " to X O 03 fc. PL, -^ C^ r2 .2 SE 48 San Diego Society of Natural History [ Memoirs The Eocene beds underlying the San Diego Mesa have a shght dip to the east. There is reason to beUeve that the pre-Phocene local forces, which evidently produced the major part of this eastward dip, may have continued or been revived at some time after the deposition of the San Diego formation, counteracting the southwestward tilting of the whole block, which probably took place at the same time, and leaving the San Diego beds with only the southward component of the dip. If allowance is made for this slight differential warping, it can be seen that the plain of the Poway terrace pro- longed would originally have been roughly parallel with the bedding planes of the San Diego formation and hence may have been coincident with the submarine profile of equilibrium that controlled the top of the San Diego formation while it was being depos- ited. In other words, it is not unlikely that the Poway terrace is a plain of subaerial denudation, possibly in part a plain of submarine denudation, which once extended southwestward into the mid-Pliocene profile of equilibrium that was controlling the deposition of the San Diego formation. The terrace is developed over a large area of Eocene rocks, and hence it is not surprising that the San Diego formation is in some cases so similar to the Eocene lithologically that the separation can be made only on the basis of fossil evidence. The material of the San Diego formation is apparently the material cut away from the terrace and redeposited. It is possible that the suggested remnants of a still higher terrace represent the old peneplained surface of the Eocene and older rocks that had been tilted downward at the time of the PHocene marine trans- gression; and, if so, these remnants should be dated physiographically from the end of the Miocene. The age of the Poway surface cannot be stated exactly, but it is clear that its pene- plaination was interrupted at some time after the middle PHocene and before or at the time of the deformation of the region. The deformation, merely because of analogy with other regions, is assumed tentatively to be middle Pleistocene. There is no evidence to show that the deposition of sediments did not continue on the level of the Poway surface from the middle PHocene through the lower Pleistocene until the time of the deformation. If it did, we should have no way of knowing it, for the sediments could only have been deposited at the outer end of the profile of equilibrium, west of the present shore line in the region now occupied by air and water. The ocean would have to attack this material and entirely remove the part that lay over the area that now is ocean before it could get in to cut the later terraces that we now know, for the deformation was not great enough in the comparatively stable region about San Diego to fault or fold these later beds down to a zone of safety. Until the time of the deformation, the Poway peneplain may have continued to develop, while the submarine surface extended itself seaward. Later the peneplain was highly dissected, while the pari; of the surface that had been submarine was entirely removed. If this is true, there is no necessity for believing that the sea withdrew and returned before the cutting of the last terraces ; for all the terraces can be explained by one gradual intermittent marine retreat from the high level point near which it stood in the Pliocene. The later history of the San Diego region is comparatively simple. At some time after the deposition of the San Diego formation, probably in the middle Pleistocene, the region was warped and tilted as outHned above. Sediments of uppermost Pliocene age and of the lower and middle Pleistocene before and during the time of the diastrophism have not been reported. After the diastrophism, the sea cut into the tilted Eocene and Pliocene sediments and produced the broad San Diego Mesa. The thin conglomeratic layer capping the mesa probably represents the material that the ocean did not carry Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 49 out across the profile of equilibrium, that was left behind because too coarse to carry. Ellis and Lee have described three beach ridges that mark very brief pauses in the marine retreat from the area. Longer halts in the marine retreat are marked by steeper slopes between the lower terraces along the coast and by corresponding river terraces, the rivers keeping pace with the subsiding sea level and cutting canyons across the mesa. As on the Bm-ton Mesa, the capping formation covers the slopes between the terraces as well as the more level parts of the terraces. The lowest terrace, known as the Nester terrace, sloping upward to the La Jolla terrace, has remnants of a fossiliferous deposit carrying a distinctly warm-water fauna like that of the Palos Verdes terrace in the Los Angeles basin. This terrace has been briefly described by Stephens.' The fossiliferous deposits may indicate a slight, temporary rise in sea level, or they may be merely better- preserved shore remnants. Finally, the shore line retired beyond the present coast, at which time the rivers cut their beds below their present levels and the ocean waves undoubtedly removed a large part of the terrain that once extended westward from the present shore. The return to the present sea level has caused the rivers to refill their valleys with alluvium. Lawson has described the San Diego Mesa, the terraces at San Diego, and the very remarkable terraces on San Clemente Island and San Pedro Hill, together with similar occurrences in middle California, in one of the oustanding papers on the geology and physiography of California-. An amplification of the part on San Clemente Island was later given by Smith.' The working out of the physiographic history of the series of marine terraces that occur at various points along the coast is a very interesting and a very important problem. As yet, however, only a little is certain of the significance of these terraces, which are important clues to the age and relationships of the Pleistocene diastrophism and later deposition. Coyote Mountain and Lower California Localities Outcrops of fossiliferous deposits occur in the vicinity of Coyote (or Carrizo) Mountain in the western part of Imperial County (once a part of San Diego County) a few miles north of the Mexican boundary. Small patches of the same deposits are known as far north as San Gorgonio Pass at the head of the Coachella Valley, Riverside County, indicating the extent of the Gulf for a brief time at least when these sediments were being laid down. Although a number of paleontologists have studied the fauna of these beds and have formed opinions as to their age, the conflicting evidence that has been recorded does not allow a satisfactory determination of the age that is any more exact than lower Miocene, middle Pliocene, or some time between. The chief cause of the difl&culty is that the fauna belongs to the Gulf of California province and is entirely different from anything else known in California. Even the Recent fauna of the Gulf of California, which is very imperfectly known, is almost as distinct from the Recent fauna of the open Pacific coast of California as is the Coyote Mountain fauna. In addition, the fossils are for the most part embedded in coarse conglomeratic sediments and occur in abnormal assemblages of numerous individuals of comparatively few species, sometimes stunted or distorted, as is often the case with faunas living at the heads ' Stephens, F.: "Notes on the Marine Pleistocene Deposits of San Diego County, California," Trans. .San Diego .Soc. Nat. Hist., Vol. 5, pp. 245-256, 1929. ■ Lawson, A. C: "The Post-Pliocene Diastrophism of the Coast of Southern California," Univ. Calif. Publ. Geol., Vol. 1, pp. U5-160. 1893. ' Smith, W. S. T.: "A Geological Sketch of San Clemente Island," Eighteenth Annual Report, U. S. Geol. Survey, Ft. 2, pp. 459-496, 1898, illustrated with photographs and a map. 50 San Diego Society of Natural History [ Memoirs of embayments in which the water is likely at times to become somewhat brackish. It may be for this reason that many of the normal constituents of the fauna are not repre- sented. The fossiliferous beds of the Coyote Mountain district overlap with marked uncon- formity the truncated edges of ancient metamorphics, Paleozoic sediments, and other formations, and in places overlie a series of Tertiary volcanic rocks such as are found almost characteristically in the middle Miocene of a number of regions in southern California. Upwards the fossiliferous beds grade into a thick series of brackish-water and non-marine sediments which may represent the remainder of Tertiary and lower Pleistocene time. As in other districts, the whole series is deformed and overlain by late Pleistocene terrace materials. The relation with the volcanics suggests that the marine beds are late middle Miocene or younger. W. P. Woodring has found basaltic flows interbedded with the fossils in one part of the district, and these basaltic flows are, then, presumably younger than the main body of the volcanics. However, the final deter- mination of the age of the fossiliferous beds should be based on the fauna. Since the Recent fauna of the Gulf of California has become better known, a large number of the Coyote Mountain species have been identified with species of the Recent fauna. There has been a tendency to correlate the marine deposits of the Coyote Moun- tain district with other formations known to be of Pliocene age and to call the age lower Pliocene. In a recent paper,' Hanna collected the current knowledge of the fauna and was inclined to believe that a greater portion of the fossiliferous formation is middle and upper Pliocene. In the systematic paleontology part of the present paper, the fossils have been considered Pliocene, usually lower Pliocene, in deference to the opinions of Arnold, Kew, Vaughan, and Hanna. If the age is Pliocene, it is not unlikely that the deposits belong to the time of maximum submergence in other regions, represented by the San Diego formation and the Pliocene deposits on Cedros Island and at numerous other places in Lower California, the age of which is believed to be middle Pliocene. On the other hand, the sequence of events may correspond to that found in northern California and Oregon, where the oldest beds of the late Tertiary sedimentary cycle are thought to be of upper Miocene age; but it seems more probable that it would corre- spond to the sequence found in less distant, southern localities. The fauna, like the middle and lower Pliocene faunas of other parts of California, contains a few distinctive species that are now extinct, at least in the Pacific. Cassis subtuberosa Hanna, for instance, has an antique appearance and recalls the large Pliocene Trophosycon of southern California. The interesting fact about these species that are no longer living in the Pacific is that most of them are conspecific with or closely related to species of the Caribbean. Consequently, if they are of Pliocene age, they must have lived over in the Pacific from the Miocene, when there was a connection with the Caribbean, and con- tinued, as they might be expected to do, until extinguished by the cold wave of the first glaciation. A number of these Caribbean species have even survived the glaciation and can be recognized in the Recent fauna. However, W. P. Woodring has recently made a careful study of the Coyote Mountain fauna, the results of which have not yet been published, and has expressed the opinion, probably because of the presence of so many Caribbean species, that the age is lower Miocene. Apparently Dickerson had come to a similar conclusion.- Hence the age must still be left in doubt. ' Hanna, G. D.: "Paleontology of Coyote Mountain, Imperial County, California," Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, pp. 427-503, 10 pis., 1926. 2 Dickerson, R. E.: "MoUusca of the Carrizo Creek Beds and Their Caribbean Affinities," Abstract, Bull. Geol. Soc. Amer., Vol. 29, p. 14S. 1918. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 51 The most promising method of settUng the question and the one that will probably be the most satisfactory in the end is to correlate the Coyote Mountain beds with similar deposits that occur from place to place along the Gulf coast of the Peninsula of Lower California. These deposits carry abundant fossils and should reveal what the normal Gulf fauna was at the time, and toward the tip of the Peninsula the Gulf fossils should mix with a Pacific fauna, the age of which is definitely known. The equiva- lent of the Coyote Mountain fauna has been reported from the vicinity of Santa Rosalia. Also, about 75 miles south of Santa Rosalia in the arroyos north of Loreto, Hanna and Hertlein have reported a fauna containing practically the whole of the Pecten assemblage, especially if P. dallasi is the same species as the P. sancti-ludovici reported by Hanna from Coyote Mountain and if "Pecten cf. mortoni Ravenel" represents a left valve of P. keepi.^ Hanna and Hertlein considered the beds near Loreto and similar occurrences that they reported in the same paper all Pliocene and correlated them with a previously reported Pliocene fauna from Maria Madre Island, which is situated off the mainland of Mexico south of the Gulf.- At the last locality diatomaceous Monterey-type shales are said to lie unconformably below the Pliocene deposits. However, the correlation of the Loreto deposits with the Maria Madre Island Pliocene is very uncertain and the opinion that the age of the Loreto deposits is Pliocene may be based on the assumption that the Coyote Mountain beds are Pliocene. On the west coast of Lower California both the Miocene and Pliocene have been definitely recognized.^ The best known Pliocene locality is on Cedros Island, where specimens were obtained that were early described by Gabb, Arnold, and possibly others. This locality can be correlated with the San Diego formation, middle Pliocene. There are also Pleistocene marine deposits in Lower Cahfornia, but the details of their stratigraphy are not well known. In places, terraces are exceedingly well developed. The San Joaquin Basin North of the Ventura basin, the best known Pliocene deposits occur in the middle and southern part of the great San Joaquin trough, the great structural depression between the Sierra Nevada and the Coast Ranges. The important works on the Pliocene deposits of this basin are by Arnold,^ Anderson and Arnold, ^ Anderson and Pack,'^ Nomland,' and Pack.^ A recent study of the moUuscan fauna from the cores of several wells drilled in the southern part of the San Joaquin basin in exploration for oil, together with the published literature on the region, indicates that the later Cenozoic history of the region is comparable to that of the Ventura basin. At the end of the Miocene, the Santa Margarita sea retreated from the edges of the basin, and terrestrial, lacustrine, or brackish water beds were deposited. In the faunal ' Hanna, G. D., and Hertlein, L. G.: Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, pp. 137-157, pi. 5, 1927. See especially localities 794 and 793 of the California Academy of Sciences on p. 144, locality 797 on p. 146, and localities 844 and 845 on p. 150. 2 Jordan, E. K., and Hertlein, L. G.: Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, pp. 209-217, pi. 23, 1926. 3 Hertlein, L. G., and Jordan. E. K.: "Paleontology of the Miocene of Lower California," Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, pp. 605-647, pis. 17-21, 1927. Jordan. E. K., and Hertlein. L. G.: "Contribution to the Geology and Paleontology of the Tertiary of Cedros Island and Adjacent Parts of Lower California," Proc. Calif. Acad. Sci., Ser. 4. Vol. 15, pp. 409-464, pis. 27-34, 1926. * Arnold. R.: "Paleontology of the Coalinga District, Fresno and Kings Counties, California." Bull. 396, U. S. Geol. Survey, pp. 22-101, ppl. 11-30. Jan. 15, 1910. = Anderson, R., and Arnold, R.: "Geology and Oil Resources of the Coalinga District " Bull. 398, U. S. Geol. Survey. 354 pp., map, 1910. s Anderson, R., and Pack, R. W. : "Geology and Oil Resources of the West Border of the San Joaquin Valley North of Coalinga," Bull. 603, U. S. Geol. Survey, 220 pp.. map, 1915. ' Nomland, J. O.: "The Etchegoin Pliocene of Middle California," Univ. Calif. Publ. Geol., Vol. 10, pp. 191-234. pis. 6-12. 1917. * Pack, R. W.: "The Sunset-Midway Oil Field, California." Prof. Paper 116, U. S. Geol. Survey, 180 pp., maps, 1920. 52 San Diego Society of Natural History [Memoirs rearrangement that took place the Pectens of the Pecten discus group became extinct and many of the other species, although not actually dying out at that time, found conditions where they had lived before unfavorable and migrated elsewhere. Around the edges of the basin there is evidence of an erosion interval and locally of an angular unconformity, suggesting that local forces may have caused the marine retreat and readvance at this time. However, the widespread occurrence of this phenomenon at times which are shown by faunal evidence to be approximately contemporaneous lends weight to the view that the forces were more than local. As the Pliocene sea advanced slowly and in an oscillatory fashion, the oldest Pliocene deposits are found only in what was at that time the lower part of the basin, and in places they interfinger with non-marine beds. Vertebrate bones found in these non-marine beds north of Coalinga afford a check on the age and confirm the invertebrate and stratigraphic evidence that the beds belong to the lower Pliocene.' These lower Pliocene beds were named by Arnold and Anderson the Jacalitos formation, and the faunal zone which they represent is known as the Chione elsmerensis zone. Nomland has already pointed out the faunal correlation with the beds at Elsmere Canyon ; and this correlation has been confirmed in the part of the present paper dealing with the Ventura basin. Furthermore, the similarity in position of the two occurrences with regard to the sedi- mentary cycle is evident and may be of considerable significance. In the middle Pliocene, the sea transgressed still farther, with perhaps minor dia- strophic readjustments, and in a number of places around the edges of the basin the tip of the marine wedge representing the time of maximum marine invasion is found over- lapping on lower Pliocene non-marine beds or older formations. Arnold and Anderson called the middle and later part of the Pliocene sequence the Etchegoin formation, believing because of the overlaps that it rests unconformably on the lower or Jacalitos beds. Nomland considered the unconformity a minor feature; and showing that the faunas in the whole of the Pliocene sequence form a natural unit, he proposed to call the whole sequence the Etchegoin formation, dividing it into four faunal zones, only the lower of which corresponds to Arnold and Anderson's Jacalitos: 4. Mya japonica zone 3. Pecten coalingensis zone 2. Turritella nova zone 1. Chione elsmerensis zone (Jacalitos) As explained in discussing the Ventura basin, Nomland's second and third zones, or the lower part of Arnold and Anderson's Etchegoin, correspond to the middle Pliocene (Pico) of the Ventura basin and to the San Diego formation at its type locality. The characteristic species that these occurrences have in common are given above. There are many other species in common also, making the percentages quite high; but as these other species occur in practically all Pliocene deposits, and many of them are also Miocene and Recent, their presence is not significant. Arnold and Anderson have recognized several other zones, such as the Glycymeris zone, the lower Mya zone, the "Mulinia" zone, and the Echinarachnius zone (the echinoid Echinarachnius now known as Den- dr aster) ; but these zones are very local in distribution. In the southeastern corner of the basin, between Tulare and Bakersfield, is a zone in the lower part of the Etchegoin in which Cryptomya calif ornica is very common. This zone is quite important, as it * Merriam. J. C: "Tertiary Vertebrate Faunas of the North Coalinga Region of California." Trans. Amer. Phil. Soc, Vol. 22. pp. 191-234, 1915. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 53 usually occurs not far above the oil-producing horizon. It is not certain whether it should be assigned to the Jacalitos or to the lower part of the Etchegoin as defined by Arnold and Anderson; but in a well drilled in exploration for oil near Tipton, Tulare County, it occurs beneath a considerable thickness of Etchegoin at the base of the marine Pliocene, and it seems to be a zone distinct from the overlying parts of the section. In the Bakersfield region it is the only marine Pliocene represented, the point of the wedge denoting the time of maximum marine invasion. It is tentatively called lower mid- dle Pliocene. During the remainder of the Pliocene the sea retreated in an oscillatory manner from its point of greatest advance. In the well mentioned above there are beds indicating at least four well-marked alternations between marine and non-marine conditions, the lowest of these beds being separated from the underlying Cryptomya calif ornica zone by a thick non-fossiliferous wedge. The non-marine beds in this upper part of the section are non-fossiliferous or contain leaves, bullrushes, etc. In the southwestern part of the basin the marine strata alternate with deposits bearing abundant lacustrine moUusca. The uppermost marine beds throughout the basin are characterized by very abundant, closely packed Mya, here referred to Mya arenaria variety japonica, and this zone is commonly called the Mya japonica zone. Mya is not only a frequenter of mud flats such as must have prevailed in the San Joaquin basin at the time, but its natural habitat is in cold or arctic waters, and its great abundance at the top of the Etchegoin and the presence of other cool-water species are taken as evidence of the approaching cold of the glacial epoch. Thus there is good reason for assigning the Mya japonica zone to the upper Pliocene and for correlating it as a mud-flat facies of the Santa Barbara zone. After the deposition of the Mya japonica zone, non-marine conditions prevailed uninterruptedly, the marine strata giving place in the southeast to alluvial deposits, and in the southwest to the Tulare lake sediments. The upper part of the Kern River alluvial formation may belong to this part of the geologic column, but vertebrate paleon- tologists have recognized in part of this formation a favma of Etchegoin age. Practically always these overlying non-marine beds, most of which are here considered lower Pleisto- cene in age, are entirely conformable with the Etchegoin, and only in one place are they reported to be unconformable.' Not until the great diastrophic upheaval of the middle Pleistocene was the great mass of the Pliocene sediments disturbed, and then the Tulare in the west and the Kern River in the east together with the marine formations were upturned against the edges of the present basin. Since that time erosion of the edges of the basin and filling of the center with alluvium is all that has taken place. The Sierra Nevada Recent investigations by Professor Blackwelder and his students have disclosed some very significant new information about the glaciations in the Sierra Nevada.^ Four glaciations can now be recognized. The oldest is known from remnants of moraines on the tops of some of the highest ridges, the position of these remnants showing that the main uplift of the region did not take place until the following interglacial age. The upUft caused the cutting by stream action of valleys to a depth of about two thousand feet, at which stage the second glaciation came on and left moraines on the valley sides and floors. After the second glaciation, stream erosion was resumed and cut the valleys 1 Pack, R. W., and English, W. A.: "Geology and Oil Prospects of Waltham, Priest, Bitterwater, and Peachtree Valleys, California," Bull. 381d, U. S. Geol. Survey, pp. 119-160, 1915, see especially p. 134. 2 Blackwelder, E., Bull. Geol. Soc. Amer., Vol. 40, p. 127, 1929. 54 San Diego Society of Natural History [ Memoirs about a thousand feet deeper. The moraines of the second glaciation are now found only in isolated patches above the shoulders of the canyons. The third and fourth glaciations, separated by a comparatively brief interval, took place almost entirely within the canyons, carving the canyon forms much as we see them today, for since the last glaciation the rivers have done but httle to obscure the glacial topography. As explained below, the discovery of the earher glaciations (only the last pair was known before), makes it possible to recognize the correlation with the three main glaciations of northern Europe, and helps materially in checking the correlation of the Cahfornia marine section with the European divisions. The Coasts of Middle and Northern California When knowledge of the geology of the Coast Ranges was still in its infancy, Lawson wrote two papers in which, among other things, he described the Merced series of middle California and the Wildcat series of northern California. ^ Even at that time the general features of the deposits and the parallel sequences of events were outlined substantially as they are known today. Soon after publishing the first description of the Merced series, Lawson added further observations and inferences. ^ Diller described and illus- trated the topographic features of northern California and Oregon. ^ Later Hsehl and Arnold described a new formation, the Purisima formation, with its type locality not far south of the type locality of the Merced;^ and this formation was subsequently mapped in the Santa Cruz FoUo.^ More recently Lawson has mapped the distribution and structure of the Merced and later formations in the San Francisco Folio." Finally, Martin reviewed the literature and summarized the stratigraphy and faunas of the various Phocene and supposed Pliocene occurrences of middle and northern California.' The literature indicates that in the Santa Cruz quadrangle where the Purisima forma- tion was first described, and northward on the San Francisco Peninsula where the Merced was first described, and in northern Cahfornia where the Wildcat series occurs, essentially the same sequence of events took place. Lithologically the three groups have a marked similarity, consisting of a basal conglomerate, a higher shale, and an overlying sandstone or conglomerate. Except for the Merced, where unfortunately most of the lower beds appear to have been cut out by the San Andreas fault, the lower parts of some of the sections include beds which have a suggestion of Miocene lithology, with brownish or siliceous shale in contrast to the more characteristic soft gray beds with occasional locally cemented hard calcareous strata of the upper parts of the sections. The faunas also have a Miocene aspect, though it will be noticed that practically all of the species thought to indicate a Miocene age are also reported either from the Merced, the upper Purisima, the upper Wildcat, or the Coos conglomerate of Oregon, all of which are conceded to be of post-Miocene age. In other words, the view that the lower parts of these formations are of Miocene age recalls the early opinions about the Jacalitos and 1 Lawson, A. C: "The Post-Pliocene Diastrophism of the Coast of Southern California," Univ. Calif. Publ. Geol., Vol. 1, pp. 115-160, 1893, "The Merced Series," pp. 142-160. : "The Geomorphogeny of the Coast of Northern California," Univ. Calif. Publ. Geol., Vol. 1, pp. 241-272, 1894, "The Wildcat Series," pp. 2S5-261. ' Lawson, A. C: "Sketch of the Geology of the San Francisco Peninsula," Fifteenth Ann. Rept. U. S. Geol. Survey, pp. 401-476, 1895, "The Merced Series" and "The Terrace Formations," pp. 459-465. ' Diller, J. S.: "Topographic Development of the Klamath Mountains," Bull. 196, U. S. Geol. Survey, 1902. < Hffihl, H. L., and Arnold, R.: "The Miocene Diabase of the Santa Cruz Mountains in San Mateo County, California," Proc. .\mer. Phil. Soc, Vol. 43, pp. 15-53, 1904, "The Purisima formation," pp. 22-28. ' Branner, J. C, Newsom, J. F., and Arnold, R.: Folio No. 163, U. S. Geol. Survey, 1909. s Lawson, A. C: Folio No. 193, U. S. Geol. Survey, 1914. ' Martin, B.: "The Pliocene of Middle and Northern California," Univ. Calif. Publ. Geol., Vol. 9. pp. 215-219, 1916. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 55 Elsmere Canyon faunas ; and the difficulty may be caused by our unfamiliarity with the cold-water northern Pliocene faunas and the confusion that has always prevailed at Coos Bay. As to the relations of the Merced and Purisima formations, it seems hardly possible that occurring so close together and having so many characters in common they could have originated entirely independently. The failure to make the correlation seems to be due to a peculiar distribution of species, the Pectens upon which most of our faunal correlations are based being absent from the Merced. According to Branner, Newsom, and Arnold: "The typical Merced fauna is distinguishable from that of the upper portion of the Purisima more by the absence of certain forms common in the latter than by the presence within the Merced of any unique species." Only the echinoid D endr aster inter- lineatus, common in the Merced, is said to be lacking in the Purisima; and wherever this species occurs in the Santa Cruz quadrangle in beds that look like Purisima, even though the beds lie directly and conformably above the basal conglomerate of the Purisima, the formation at that place is mapped as Merced. Unfortunately, nowhere has the Purisima fauna been found above the Dendraster interline alus beds, but one of the missing Pectens was found by Martin in the area at Pillar Point which is likewise mapped as Merced. Furthermore, Pecten turneri from the Merced north of San Francisco appears to be only a poorly preserved Pecten purisimaensis. There is an upper or Pleistocene section of the Merced separated from the lower by a fault or unconformity, but it is not represented in the Purisima area and does not figure in the above discussion. Thus it appears that the Merced series, though all of the lower part except the very base is lacking, and the Purisima series, though the upper part is in most places removed by erosion, represent essentially the same unit of deposition or sedimentary cycle, and that the Wildcat series of northern California is also essentially the same. The nature of the break between the Pliocene and the Pleistocene parts of the Merced series is masked by a landslide over the beach section, and apparently the upper Pliocene is missing. All the species in the upper Merced are still living, and the deposit correlates well with the lower Pleistocene in southern California. The folding and faulting of the Merced series and the uplift of the Montara Mountain block came afterwards. Unconformably above the Merced series and the older (Mesozoic) rocks alike lie the prac- tically horizontal, unconsolidated, upper Pleistocene terrace deposits. Lawson has described two old terraces on the back slopes of Montara Mountain near the type locality of the Merced. They are represented by the tops of Sawyer and Buriburi ridges at elevations of 1150 and 700 feet respectively; but as these ridges are separated by the San Andreas fault, it seems not unlikely that the two levels represent the same terrace. This terrace is probably the equivalent of one of the terraces along the coast, perhaps of approximately the same age as the Timber Canyon surface of the Ventura basin; but it has been maturely dissected, and it is barely possible that it was cut, like the Poway terrace at San Diego, during the deposition nearby of the Pliocene and Pleistocene marine sediments, later being uplifted with Montara Mountain at the time of the middle Pleistocene deformation. Diller (above referred to) describes a number of old land surfaces in northern Cali- fornia, some of which are probably related to the Wildcat series. Diller considered the Wildcat series Miocene because of Dall's determination of the fauna, although Gabb and Merriam and Lawson had previously recognized the Pliocene age of the series. Even Martin thought that there might be some separation of the basal Wildcat beds and "Bear River Miocene" into an upper Miocene part of the series, but it now seems probable 56 San Diego Society of Natural History [Memoirs that the whole represents a single Pliocene unit. The Klamath peneplain is the most clearly marked of the surfaces recognized by Diller. Apparently Diller thought that this ancient peneplain was in process of formation up to and including the time of deposition of the Wildcat series and that not until after the deformation of that series (now believed to have taken place in the middle Pleistocene) was it encroached upon by a surface of lower base-level. Its age would then be lower or middle Pleistocene. It is probable that the old peneplain had been warped and partially uplifted at the time when the coastal area about the mouth of Eel River was depressed to admit the invasion of the lower Pliocene sea. Remnants of old terraces in the San Diego region must have been uplifted before the formation of the Poway terrace and may correspond roughly to the early stage of the Klamath peneplain. The end of the Miocene is known to have been a time of general deformation, the only important one before the mid-Pleistocene revolution. This earlier period of deformation was formerly thought to have come in the middle Miocene, but in some cases at least the supposed Miocene beds above the angular unconformity (Sargent oil field, Santa Cruz quadrangle, etc.) have since been shown to be Pliocene. If this is the case, the early stage of the Klamath peneplain, and possibly the old San Diego terraces, may be assigned tentatively to the end of the Miocene. With the uplift of the highlands, may have been formed the older valleys of the Klamath region; and at the time of maximum marine invasion, in the middle Pliocene, may have been formed the peculiar semi-marine inland deposits at Hay Fork described by Diller. Later, perhaps in the mid-Pleistocene, though there is no evidence for the time except analogy, the Wildcat series (like the Merced and like the beds in the Ventura basin) was deformed and the whole of the north coastal region was uplifted in stages, forming the marine and the later valley terraces, the sea finally retreating to a position below its present level and not returning until Recent times to cut away the outer edge of the last terrace. There seems to be no conclusive evidence of more than one great uplift when the sea level stood at the continental border and no reason to believe that the uplift came before the upper Pleistocene or earlier than the time just succeeding the middle Pleistocene deformation. Diller's postulation of two such uplifts, the first fol- lowed by subsidence, does not seem to be well substantiated. The Coast of Oregon and Northward In the Coos Bay Folio, Diller described some later Tertiary and Quaternary deposits as the Empire formation and the Coos conglomerate respectively.' Later, Dall mono- graphed the fauna,^ assigning the Empire formation to the Miocene and the Coos con- glomerate to the Pleistocene. Much later, Howe restudied the section described by the older workers and pointed out' that the fauna listed by Dall from the Coos conglomerate contains only three species not contained in the underlying Empire formation and that of these three Dall recorded only one as living. Hence Howe concluded that it is illogical to consider the Empire Miocene and the Coos conglomerate Pleistocene; and he assigned both to the Pliocene, while recognizing an erosion interval between them. Arnold and Hannibal," and Hertlein and Crickmay^ have also published papers, one before and the 1 Diller, J. S.: Folio No. 73, U. S. Geol. Survey, 1901. ' Dall. W. H.: "The Miocene of Astoria and Coos Bay, Oregon," Prof. Paper 59, U. S. Geol. Survey, 278 pp., 23 ppl., 1909. 3 Howe, H. v.; "Faunal and Stratigraphic Relations of the Empire Formation, Coos Bay, Oregon," Univ. Calif. Publ. Geol., Vol. 14. pp. 85-114, 1922, especially p. 87. * Arnold, R., and Hannibal, H.: "The Marine Tertiary Stratigraphy of the North Pacific Coast of America," Proc. Amer. Phil. Soc., Vol. 52, pp. 559-605, 1913, '> Hertlein, L. G., and Crickmay, C. H.: "A Summary of the Nomenclature and Stratigraphy of the Marine Tertiary of Oregon and Wash- ington," Proc. Amer. Phil. Soc, Vol. 64, pp. 224-282, 1925. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 57 other after Howe, summarizing the Tertiary stratigraphy of the Northwest and men- tioning the Coos Bay formations. It is difficult from the Uterature extant to form a definite opinion of the age of these Oregon beds. The Coos conglomerate, as mentioned by Howe, lies unconformably under horizontal terrace deposits and must therefore antedate the mid-Pleistocene deformation. Judging by its fauna and induration it seems probable that Howe was right in considering it Pliocene, though it must be remembered that many of the species reported from it, as is recognized by all writers on the subject, are redeposited in large and small fragments from the Empire formation. For the time being then, the occurrences in the Coos conglomerate will be reported as Pliocene; and merely because the weight of opinion seems to point this way, not because the evidence is believed to be any stronger for this view than for the other, occurrences in the Empire formation are reported as upper Miocene. The stratigraphic relations and the similarity of the Purisima and lower Wildcat faunas even favor Howe's view. Ball's refusal to recognize Recent species may have given the fauna an artificial appearance of antiquity. On the other hand, the Em- pire formation is correlated with the Montesano of Washington, which is still considered upper Miocene. 1 To follow out to logical conclusions the views previously expressed in this paper would necessitate placing both the Empire and the Montesano formations in the lower Pliocene because of their stratigraphic and faunal relations ; but reasoning based on the scanty evidence available in the literature is not sufficiently reliable to warrant .so radical a change. Ball has from time to time reported Miocene and Pliocene occurrences in Alaska, and in some cases references to these reports are included in the systematic paleontology part of the present memoir. Without further reference to the literature of Alaska it would be unwise to discuss the age of these deposits, though it might be noted that Ball was always inclined to assign to formations too great an age. The raised beaches at Nome, for instance, sound more like Pleistocene than Pliocene.- A recent reviewer's note suggests that later information is available. Br. Stephen R. Capps has recognized four glaciations in Alaska.' Historical Summary of Conditions in California At the beginning of the Miocene the region extending from the present sites of the Sierra Nevada and Cascade ranges to the edge of the continental shelf was a region of fairly low relief. Fine-grained Oligocene sediments had been deposited in Washington and Oregon, and a small belt of shales with some sandstone had been deposited in middle California; but the rest of the region, so far as there are records, seems to have been land. In southern California the conglomeratic sandstones of the Sespe formation indi- cate that there must have been mountains in the distance, but the remarkable regularity and extent of these non-marine beds indicates that the surface on which they were depos- ited must have been broad and very uniform. Biastrophic movements or crustal warping on a large scale caused the lower Miocene or Vaqueros sea to transgress over this surface, depositing from middle California south to Orange County a basal sandstone of very uniform character with fossils of littoral habit. That this transgression was gradual is shown in the south by an interfingering 1 Weaver, C E.; "Tertiary Faunal Horizons of Western Washington," Univ. Wash. Publ. Geol., Vol. 1, pp. 1-67, 1916. 2 See Moffit. F. H.: "Geology of the Nome and Grand Central Quadrangles, Alaska." Bull. 533, U. S. Geol. Survey. 1913. especially pp. 40-49. ' Science, N. S., Vol. 71, Supplement, p. xii, Jan. 3, 1930. 58 San Diego Society or Natural History [Memoirs with the terrestrial Sespe deposits; and consequently the Vaqueros formation does not always and may not ever in the regions now exposed to view represent the very bottom of the Miocene or the beginning of the crustal warping, but was deposited as the sea moved inwards at higher and higher horizons. As the shore phase moved eastward finer-grained sediments were deposited to the westward, gradually grading upward, with or without local break into the middle Miocene. As already explained in discussing the Ventura basin, the Miocene sequence exposed along the present coast from the Salinas Valley southward seems to be remarkably constant. Overlying the Vaqueros sandstone, sometimes with a gradational contact passing through buff sandy shales, and sometimes with a comparatively abrupt contact passing directly into soft gray micaceous or hard black shales with characteristic cal- careous or dolomitic strata or concretions that weather a bright yellow color, are the siliceous shales, usually opalized below, but normal and finely laininated in the middle, and very light and porous at the top. The siliceous shales are usually assigned to the Monterey formation, middle Miocene. They are composed of volcanic ash and diatomaceous remains, the relative amounts of which have been the subject of consider- able discussion. Recently there has been a tendency to call the black shale overlying the Vaqueros sandstone Temblor, because it has been correlated by means of foraminifera with the middle Miocene shore phase in the San Joaquin basin, known as the Temblor formation. Among the mollusks, a marked change in fauna took place when the advancing Miocene sea had reached about half way to its position of maximum extension. The shore phase deposited from then on is usually called Temblor; and if the foraminifera, as mentioned above, show that certain shales deposited oceanward were laid down contemporaneously, the correlation is important. However, the beds correlated constitute more a faunal zone than a formation; and their position in the sedimentary cycle as the upper Vaqueros shale oceanwards and the basal Monterey sandstone shorewards should not be lost sight of. It appears now that the typical Temblor represents the lower middle Miocene and that the tj^ical Monterey represents the upper middle Miocene ; and such a relationship is quite to be expected if the former is the base and shore phase of the middle part of the Miocene cycle and the latter is the upper and oceanward phase. On the other hand, wherever local circumstances may have brought about shore conditions in the upper middle Miocene, the presence of Temblor fossils should not cause surprise ; nor should the presence of Monterey fossils in lower middle Miocene sediments deposited in the ocean- ward parts of basins be wondered at. Perhaps foraminifera are less easily affected than mollusks by differences in facies, for their light tests are easily transported into all the different phases of a horizon. For this reason it may be possible with their help to recognize the Temblor as a horizon in addition to its being the shore and basal phase of the Monterey. In the middle Miocene the shore line reached the Sierra Nevada, which even at that time must have had in places very steep slopes, for sands and conglomerates locally containing huge boulders, as in the southern end of the San Joaquin basin, were deposited by torrents flowing out from the slopes. Similar deposits on the west side of the San Joaquin basin indicate that there may have been islands or a ridge in that direction dividing the basin from the open ocean. The climate must have been arid, as it is today, and the torrents infrequent, for terrestrial sediments reached but a short distance from shore, and over the greater part of the submerged region, inland as well as along the present coast, fine white siliceous shales, very characteristic of this horizon, were depos- Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 59 ited. With the few exceptions indicated by coarser sediments, the conditions of deposi- tion in California seem to have been much more quiet and more uniform than topography hke the present would allow. At least some of the islands that are recognized to have been present were probably volcanoes pouring forth lava and tufTaceous material and suppljdng silica favorable to the growth of diatoms. In Washington and Oregon similar deposits were being laid down, except that the shales contain less siliceous material and the northern faunas are somewhat different. The northern occurrences include the Astoria beds of Oregon and the Clallam formation of Washington. At the same time, in the parts of the coastal belt from Washington and Oregon to California that remained land, particularly in northern California and probably in the San Diego region, the forces of erosion were presumably busy removing the remaining irregularities from the already nearly fiat land surface and wearing it down to a peneplain. It was formerly thought that at the end of the middle Miocene violent diastrophic movements upset the peaceful regularity of these processes, folding and faulting the newly laid deposits. It was thought that along the coast from middle California northward new areas of submergence were formed and a new cycle of sedimentation inaugurated. It is even now recognized that local disturbances and readjustments of this sort occurred, notably in the Santa Monica Mountains and in the San Luis Obispo region; but now more and more of the deposits overlying the stratigraphic break have been found to be Pliocene instead of Miocene in age, first the Jacalitos formation of middle California with which Pliocene vertebrates were embedded, then, in order, the Elsmere Canyon beds, the supposed upper Miocene ("San Pablo formation") of the Sargent oil field, the lower Purisima of middle California, and the lower Wildcat of northern California. Even the Empire of Oregon is being questioned, and if it also goes, the Montesano of Washington will go with it. If the formations mentioned above are eliminated from the upper Miocene, the evidence from deposits undoubtedly of that age indicates consistently a normal con- tinuation of the processes of the middle Miocene. There was a slight diastrophic read- justment, and the sea covered a few areas where it had not been before and abandoned a number of others. The major basins continued to fill up, and most of them, like the San Joaquin and Ventura basins, became very shallow toward their heads. Beds packed with oysters, some of them of very large size, were deposited, and in other places beds made up of large numbers of individuals of other single species, as if the water were becoming brackish. The upper Miocene is represented in middle and southern California by the Santa Margarita formation, which has been called the San Pablo group in the San Francisco Bay region and has been divided into the Briones, Cierbo, and Nivoly. Not until the basins had become very much restricted and deposition had almost ceased did the main widespread diastrophic movement take place. Then the Pliocene marine cycle was inaugurated. The older sediments were folded, the land areas were warped so that new basins were formed and parts of the land areas were uplifted, starting a new erosion cycle and causing the streams to wash down coarser material. It is probable that the basin areas, being the weakest parts of the crust, would be affected most, especially around the edges, where bending or faulting would be con- centrated, and that the stronger parts of the more resistant land masses would be uplifted with Uttle or no deformation, preserving nearly intact the old land surfaces. Thus an early stage of the Klamath peneplain of northern California may be dated from this time, and possibly the older surface that appears as the highest terraces in San Diego County back 60 San Diego Society of Natural History (Memoes of the Poway terrace. It is also probable that the major structures of the Coast Ranges were outlined at this time, and the basins as we know them today, though the great move- ments that brought about the present topographic relief did not take place until later. Marine waters reinvaded the old basins, in places encroaching on the borders of the older rocks surrounding the basins, and invaded in a number of places entirely new areas of deposition. The marine overlap is usually recognizable by a littoral zone of coarser sediments, sometimes overlying an angular unconformity, the sediments above usually having a somewhat different lithology of grayish, softer sandstones and clays with very little of the siliceous material characteristic of the Miocene. In the centers of some of the larger basins, however, like the Ventura and Los Angeles basins, sedi- mentation seems to have been continuous from the Miocene into the Pliocene, and the line must be drawn chiefly on the basis of paleontologic evidence. The fauna of the lower Pliocene shows a change of character, though not always a marked change, from that of the upper Miocene. Several common species of Pectens dropped out or became scarce, and the last members of the genus Agasoma died out. Species and groups of modern character appeared. A few species more characteristic of the Miocene survived into the lower Pliocene, but most of them disappeared before the middle Pliocene. The names of the formations representing this basal Pliocene have already been mentioned : the Jacalitos, the Elsmere Canyon beds (+the Santa Paula formation), the lower Purisima and the lower Wildcat, and, very hypothetically, the Empire and Montesano formations of Oregon and Washington. In the middle Pliocene the marine invasion reached its maximum in most places and began a long, halting retreat. Whereas the fauna of the lower Pliocene consists entirely of warm-water constituents, that of the middle Pliocene begins to show toward the end an intermixture of newly arrived northern species. The various formations have been described above, and little can be added here: the San Diego, the Pico, the middle or lower Etchegoin, the Merced, the upper Purisima, the upper Wildcat, perhaps the Coos conglomerate. In the highlands the post-Miocene diastrophism had inaugurated a new erosion cycle, and during the lower and middle Pliocene river valleys were probably being cut as a result of that uplift. The erosion cycle may have reached late maturity in upper Pliocene or lower Pleistocene time. The upper Pliocene, as has already been pointed out, is characterized by a fauna containing as large a proportion of species now living only in northern latitudes as is found in any of the coldest zones of the Pleistocene. The filling up of the basins and the restriction of the areas of deposition give the end of the Pliocene an aspect strikingly like that of the end of the Miocene; but the colder climate indicated by the fossils is something new and unusual. It is the cause for the extinction of so many species and the reason for the separation of the Tertiary and Quaternary periods. The upper Pliocene is represented by the Mya japonica zone of the San Joaquin basin and by the Santa Barbara beds of southern California. Until a short time ago the lower Pleistocene was included in the Pliocene, partly because the Recent fauna was not so well known and many of the species now known to be still living were then thought to be extinct, and partly because the formations of this age were involved along with the Pliocene in the great diastrophic revolution of the late Cenozoic. Three lines of evidence now show that these beds are lower Pleistocene: (1) a revision of the faunas and check-lists shows that practically all of the species are still living; (2) the time of the diastrophic revolution has been dated by physiographic and vertebrate paleontologic evidence both in eastern California and on the Pacific Volume 1 Pliocene and Pleistocene Mollusca of California 61 n < o < O o o fa o ;z; o H C 3 3 « = Ph o a c3 g- Pu3 S o ■e2 C3 O Em ^ O a; 5 in o a. S =3 o O c » a; ° S Ph S J3 3 o £ £ g. ■5« £iia; g 3 d £-rt-c^g S « 2-^1 3 " f" I- 3 !r, o) Ph o o O o c. o 03 ? ?- 03 «: i** VS 3 -^ 03 §•2 ip' 03 £"0! ^ 3 -O 3 ^ £ oaH r- O 15< S 03= =e ^^ to re r; 53 o '"'= g-5 5 c ° ^ .. 3.S0- 03 2 "o o C3 03 pa c NpH -'i-s i, i 63 ~ ^ g - 5 *- c ~ S C "^ 3S o3 ^ '^ 00 s c 0 2 fl> rl CI '^ -w W !> •SJ, bt- e n c IH 03 > m Pi K ^ n W ^£. 0^ 01 o ao. t- o ^ s J?'. .fi & 01 cu Ti ja c , ^^ Ol S !n s S w ,°° e OJ W-2 3 0 0 c ?,s 03 ■-5 s § 00 so (^ ^^ ^ O eo C -*^ "^ O 0 03 s S .2 (h 0 T3 f2 > ^ u 35 tx OJ OJ & ^ 0 O) 0 hapaj ^? t;2 ■28i •E-O § -*^ 3 ^ ^' p3 e.s rz rr/ ^ £ III GO «^ O 0) >- £ m S 3 a* O X § .9 E-2 ^►9 62 San Diego Society of Natural History [Memoirs slope (a Pleistocene horse tooth was even found embedded with the marine deposits in the Ventura basin), so that it is now recognized that the diastrophism took place well within the Pleistocene; and (3), as explained below, correlation with the European section shows that the underlying Santa Barbara beds correspond to the uppermost Pliocene of England and Sicily. The Ventura and Los Angeles basins are keys for the demonstration of the relations of California Pleistocene deposits. The Las Posas zone of the Ventura basin, formerly called basal Saugus, overlying the Santa Barbara zone, has at its base north of the Santa Clara Valley a fossiliferous marine conglomerate or sandstone that represents the littoral phase of a marine overlap. The fauna, in striking contrast to that of the underlying beds, is of a rather warm-water complexion, indicating ocean temperatures at least as warm as those of today and probably warmer, a condition that is to be expected of interglacial ages. The same zone has recently been recognized in the Los Angeles basin, where colder- water faunas occur above it and still higher faunas denoting a return of milder tempera- tures, all apparently in sequence with the Pliocene, and separated from each other by only minor unconformities. The lower Pleistocene sedimentary cycle is unquestionably of much shorter duration and more limited distribution than either the Miocene cycle or the Pliocene cycle, for the deposits representing it are found only along the present coastal strip and short distances inland in the Ventura basin. The deposits of the end of the cycle, as in the other cycles, are the most limited in extent. Besides the occurrences in the Los Angeles and Ventura basins, the lower Pleistocene is represented by the upper Merced of middle California and possibly by the uppermost part of the Wildcat formation of northern California. These beds are all unconformable below the upper Pleistocene terrace deposits. Non-marine deposits of the same age inland in middle California are known as the Paso Robles, Tulare, and Santa Clara formations. The land surface that developed while the Pliocene and lower Pleistocene sedi- ments were being laid down has been recognized in a number of places. Presumably its slope was approximately represented oceanward by the plain of aggradation of the top of the marine sediments as originally deposited, and inland by the top of non-marine sediments. The Poway terrace at San Diego, the Perris peneplain in the Los Angeles region, the westward slope of the Sierra Nevada, the mature surfaces of many of the up- lifted blocks in the Coast Ranges of middle California, and the Klamath peneplain or one of the younger peneplains recognized by Diller in northern California may all be remnants of the same pre-deformation surface. In southern and middle California the remnants of the pre-deformation surface are bounded by fault scarps of high relief and are in this respect very different from the remnants of the oldest post-deformation surface, which does not seem to have been subsequently much disturbed. Not until the middle Pleistocene did the great diastrophic revolution take place. It seems, judging from the tremendous structures formed and the unconformities pro- duced, that the post-Miocene movements were insignificant in comparison. In many places thousands of feet of sediments were faulted, upthrust, folded, and sometimes overturned. Rocks from the Mesozoic to the Pleistocene were involved, the youngest beds taking part even in the overturning. The present relief of the Coast Ranges was mostly produced by this revolution. The time when the revolution began and the duration of its maximum activity are subjects of considerable interest. In the Los Angeles basin we know that it began after the deposition of two cold temperature zones and two milder temperature zones. In the Sierra Nevada the uplift began after the first glaciation was over. If the beginning Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 63 of the deformation was essentially contemporaneous in the different parts of the state, then the first Sierran glaciation should correspond to the second cold zone of the marine record, that is, the Timms Point zone, formerly called the Deadman Island "Pliocene." As shown below by the independent correlation of the marine section and of the Sierran glaciations with the European divisions, the assumption of contemporaneous deformation in the Sierra Nevada and in the Los Angeles basin is correct. The uplift of the Sierra block may have caused the compression of the coastal belt; or in any case, whatever the cause of the compression, the forces seem to have been so great that all of the basin areas, which are the weak places where the crust is in the habit of making adjustments, were affected. It seems probable that the forces that accomplished this great compressive deformation had been building up for a long time before the storm broke. They may have been responsible during Pliocene and even earlier times for the downpressing of the great sagging arches of the basins of deposition and for the minor unconformities in the sedimentary series. When, however, the total resistance to the horizontal pres- sures was finally overcome, the forces were released and during a comparatively short period no formation not protected by unusually strong underlying material escaped deformation. For practical purposes the beginning and ending of this main period of folding and overthrusting can be assumed to have taken place at approximately the same time in the various regions throughout California. California was left with a network system of folded, upthrust, and depressed blocks. The broad terrain of high relief so produced probably extended with about the same char- acter west of the present coast, perhaps nearly to the outer edge of the continental shelf. The western part was probably partly submerged, the higher blocks projecting from the water as islands much as they do today. The shifting of loads caused by the deformation apparently necessitated readjustments of an isostatic nature so that some overloaded blocks began to sink, dragging down small adjacent masses, while others that had been shoved down by lateral pressures were starting to rise. On the rising blocks, like San Clemente Island and San Pedro Hill, a score or so of well-defined wave- cut terraces are found, ranging in height up to 1500 feet. Santa Catalina Island, which lies halfway between San Clemente Island and San Pedro Hill, bears no terraces and is generally thought to have been a sinking block. On the land, some regions exhibit stream terraces, whereas others are drowned in alluvium. That the readjustment was differential is also shown by the fact that waters now standing uniformly at the height of the highest marine terraces would be many feet deep over such inland places as Bakersfield, San Bernardino, etc., and there is no evidence that such an inundation took place in the Pleistocene. The nearly horizontal position of the terraces indicates that the differential uplift took place after the regional compression and folding had ceased. The readjustments, which took place for the most part along normal faults, were presumably most rapid at first, gradually becoming less and less active. It seems prob- able that the important part of the differential readjustment, like the main part of the compressive deformation, was accomplished in a comparatively short period, for in va- rious places in southern California an old post-deformation physiographic surface, best represented by the Timber Canyon fanglomerate of the Ventura and Los Angeles basins, was developed, and since the time of its development very little faulting has taken place. Very seldom are the younger marine terraces faulted or deformed in any way except for very broad warping which is usually so gentle that it is not visible to the eye. The submarine relief of the continental shelf shows no obvious features that require very recent, locally differential movements for their explanation, except perhaps the absence 64 San Diego Society of Natural History [Memoirs of terraces on Catalina Island. The higher terraces on other blocks must have been formed dm-ing the time of differential movements, and their absence on Catalina Island can readily be explained by sinking at that time; but the younger terraces of the other blocks, if formed after the time of differential movements, might be expected to appear on Catalina Island. However, their absence, if they are totally absent, may be explained by the scarcity of gentle slopes such as have provided the most favorable places for the cutting and preservation of terraces on San Clemente Island and at San Pedro. Terraces cut in steeper slopes, other factors being equal, are narrower, and after uplift are closer to shore and more likely to be entirely removed by the later work of the ocean. Rem- nants of terraces on the northeast side of San Clemente Island are infrequent and obscure. Thus the submerged part of the continental border, as described by Lawson,' seems to have essentially the same forms as the exposed part, except insofar as the relief has been modified and reduced by more prolonged marine terrace cutting and submarine deposition in the hollows when the sea level was lower than at present. After the period of differential readjustment was over, the whole western border of the continent seems to have been uplifted gradually as a unit, or the sea level may have subsided eustatically,^ or both processes may have worked simultaneously. In southern California an old land surface, in many places covered with alluvium, seems to have remained essentially intact, except for erosion, since its formation. The youngest series of marine terraces exposed at various places along the coast from San Diego to Oregon seems to be remarkably uniform in general features, though the individual terraces vary in number and height because of minor local warping. The outer edge of the youngest marine terrace also varies in height according to the amount the ocean has cut it back, the back slope usually rising to an altitude of 100 or 200 feet, but the outer edge being lower. In places this terrace bears a thin fossiliferous covering. The faunas of the Nester terrace at San Diego and of the Palos Verdes terrace at San Pedro are of distinctly warm-water facies so that these two occurrences can be correlated with moderate confidence; but the fauna in the terrace east and west of. Santa Barbara is not essentially different in temperature facies from the fauna living oflf the coast there today, and hence its correlation with the more southerly terraces must be regarded as somewhat doubtful. The faunas in more northerly occurrences of this or similar terraces are not well known. The correlation of the terrace at Santa Barbara with the Palos Verdes and Nester terraces almost necessarily involves the assumption of a land barrier in late Pleistocene time between Santa Barbara and San Pedro to protect the warm waters of the southern coast from the northern currents, an assumption which additional evidence may be expected at some time to justify. The youngest terrace (or terraces, if the similar occurrences at the various localities are not to be correlated) contrasts with the older terraces in frequently bearing on its surface deposits containing well-preserved fossils. Fossils have in nearly every case been leached out of the deposits on the older terraces, if indeed the deposits have not been entirely washed away, so that the older terraces can be recognized as marine only by their form and by the presence of Pholad borings in the underlying rock. Also, the topography of the youngest terrace is much younger. The little streams have cut their beds practically to the bottoms of the steep slopes below the older terraces, so that they flow out at grade onto each lower terrace ; but they traverse the surface of the youngest » Lawson, A. C: "The Continental Shelf off the Coast of California," Bull. National Research Council, Vol. 8, Pt. 2, pp. 1-23, 1 fig., 1924- ' The change of sea level up to 300 feet, more or less, by the withdrawal and return of water to the oceans by glaciation and deglaciation must be considered as a probable alternative to continental uplift and depression. See Daly, R. A.: "Swinging Sealevel of the Ice Age," Bull. Geol. Soc. Amer., Vol. 40, pp. 721-734, 1929. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 65 terrace in shallow troughs and drop from hanging valleys over the sea cliff. The young- est terrace, however, is not so young as it would appear, for the youthfulness of the remnants that we now see is due to their having been protected by a wide seaward exten- sion of the terrace in past times. We are so used to the steeply shelving coast of Cali- fornia that it is hard to imagine a wide, shallow submarine slope extending far out from the shore in late Pleistocene time, and yet such a condition must have prevailed in most places along the coast, for the ocean had been gradually retreating from its early Pleisto- cene high level. The bottom of such a gradually retreating ocean should have such a shallow slope. That the continent' as a whole stood higher than at present and that the ocean was for a considerable time during the erosion interval following the cutting of the youngest exposed terrace nearer the continental border than now is shown by the present over- deepened condition of the off-shore areas, by the submerged terrace or terraces developed almost universally on the top of the continental shelf, and by the overdeepened main stream valleys on the land now filled with alluvium. The amount of erosion done at this time by the ocean has not been fully realized. Many large land areas west of the present coast were exposed, cut into, and reduced in extent. It is not unlikely that some of the present islands, at first connected with the mainland, had their connections severed by erosion and drowned by the later submergence. The original outer edge of the youngest terrace of which remnants are now exposed was cut into, and the previous deposits of middle and later Pleistocene as well as of older formations were cut away and carried out partly to fill up the depressed areas on the continental shelf or were removed to the outer slope of the shelf. Later, the ocean returned to cut a higher notch in the youngest exposed terrace, using the material taken from this modern notch to obscure the form of the previous notch. All this time the marine erosion was much more rapid and effective than the work of the little streams along the coast, which were never able to cut down their gradients to the low base level set by the ever advancing shore, and for this reason the thin fossiliferous deposits on the vouneest terrace have not been attacked and removed. In some regions it even seems as if the ocean when returning again to a higher level had risen slightly above its present position, for rivers have filled their valleys with alluvium to somewhat higher levels which they have only very recently cut into. Recent sinking has been noted in the vicinity of San Francisco Bay. It has even been suggested that the returning sea cut the youngest exposed marine terrace described above and left on it its fossiliferous deposits; but in the San Diego and San Pedro regions, and hence probably also in the other regions, the youngest terrace can be seen to be part of the older series, its warm-water fauna containing a few extinct species, and as explained below, belonging to the last interglacial. The recent rising of sea level above its present position cannot have been very great, for if it had been, the youngest exposed marine terrace (the outer edge of which was then farther oceanward than now) would have been over- flowed. Possibly the Goleta and Seacliff localities on the Santa Barbara terrace represent such an overflowing, but the presumption is against it. The recent erosion of the alluvial filUng of the valleys may be due as much to the shortening of the river profiles by the horizontal cutting of the ocean as to the rising and sinking of sea level. The slight sinking of the land around San Francisco Bay may have been local. The initial flooding of the bay must have taken place when the ocean returned from its low-level stage, after the 1 In writing this discussion no attempt was made to distinguish between tlie sinking of sea level and tlie rising of tte land, or vice versa. All that is meant by such statements is a relative change of level. The idea of glacial control referred to in the preceding note suggests that the particular change of level referred to here is a change in sea level. This theory would explain the cooler water faunas in the low terraces at Seacliff and Goleta, east and west of Santa Barbara. 66 San Diego Society of Natural History [Memoirs Sacramento River had cut the Golden Gate gorge during the time when the ocean was at its low level. The drowned shore line in the bay has been preserved because of the relative impotence of wave action in the bay; but all along the open coast the embayed shore line has been obliterated by the horizontal cutting of the waves, and along the open coast the marine erosion cycle may be described as approaching maturity. Correlation with the European Standards The European Section A comparison of the general features of the California and European sections may lead to a definite establishment of the correlation between them. Articles on the later Tertiary and Quaternary deposits of Europe help to make evident the parallelisms. In the Pliocene, the account given by Harmer of the English Pliocene is most useful,' and for the sake of brevity the English Pliocene alone will be considered. In the Pleisto- cene, Brooks' summary of the vast literature on the northern European Quaternary deposits is unusually good.- It is now generally agreed that there are no Miocene marine deposits in the British Isles. In the earliest Pliocene, however, southeastern England was depressed and the sea transgressed from the northeast over the early Tertiary and older formations, which had just been deformed, during the Miocene, by the peripheral disturbances of the Alpine revolution. Basal conglomerates known as "Boxstones" are found overlying a peneplain or plain of marine denudation in East Anglia and underlying the Coralline and Red Crags. Other beds in a similar position at Lenham carry a more extensive fauna, and this fauna, because of the inclusion of some species more characteristic of the Miocene, has in the past been assigned by several paleontologists to the Miocene. How- ever, a more thorough study of this fauna indicates that it is more closely related to the fauna of the Coralline Crag, and stratigraphic studies have connected the Lenham beds with the Diestien of Flanders, which overlies the Miocene and has always been considered Pliocene by Belgian geologists. After the deposition of the Lenham beds in the south of England, the region was gradually tilted northeastward and the shore line began a slow retreat that lasted throughout the remaining part of the Pliocene. The Coralline Crag is the first of the zones recognized in the littoral deposits left by the retreating sea. Its fauna is distinctly southern. Most of the species that have survived are found living in the Mediterranean or along the coasts of Portugal and southwestern France. Northern species are very rare. In the next zone recognized, the Red Crag, the southern species began rather quickly to die out, and boreal species began to take their places. Tliis change is attributed by English geologists to the breaking of the direct channel connecting the Anglo-Belgian basin with the south Atlantic and at the same time the exposing of the coast to the colder waters of the northwest. Harmer makes the following remarks: "As far as the evidence goes, the different fossiliferous zones of the Red Crag do not overlap, occurring in horizontal rather than in vertical sequence. As we trace the northward retreat of the Crag Sea from Walton-on-Naze on the south to Weybourne on the Norfolk coast, we find the various deposits to assume regularly a more recent as well as a more boreal and eventually a sub-arctic character." ' Harmer, F. W.: "The Pliocene Mollusca of Great Britain," Introduction to Volume II, found on pp. 485-505 in Vol. 72 of the Mono- graphs of the Palffiontographical Society, December, 1920. 2 Brooks. C. E. P.; "The Correlation of the Quaternary Deposits of the British Isles with those of the Continent of Europe." Annual Report of the Smithsonian Institution for 1917, pp. 277-375 (Publ. No. 2507), 1919. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 67 Although geographical changes may account partly for this change in thermal facies, they seem hardly adequate to explain why a fauna of south European character should give place to one of sub-arctic character. A more evident explanation lies in the approaching cold of the first glacial age, which, whatever its cause, seems to have been of more than local distribution. In the upper Pliocene, or Icenian Crag, the basin continued to fill up and the shore Hne to retreat. Most of the species characteristic of the earlier Crag horizons had dis- appeared and the fauna had become distinctly arctic and distinctly modern in compo- sition. Because of the filling up of the basin, the waters became slightly brackish in facies, the estuarine Mya arenaria being common along with the more normal Astarte borealis and other cold-water species. Harmer even suggests that "the advance of the Scandi- navian ice may have wholly or partially blocked the northern outlet of the Icenian sea, which may have still received volumes of fresh water (at least in summer) from the rivers of central or southern Europe." A higher horizon is characterized by abundant Tellina balthica. It is interesting to note that in the English type section of the Pliocene there is an extremely cold-water zone at the top, but that no evidence has been found of a corre- sponding glaciation in the British Isles. Nevertheless, it is now generally agreed that this cold-water marine zone corresponds to the first or Giinz glaciation in the Alps. Brooks' correlation of the Cromer forest bed with the Tegelen stage, or first interglacial on the continent, requires also this correlation. Similar cold-water marine beds, char- acterized by boreal and sub-arctic species are found at the top of the Pliocene in Sicily. It is very unlikely that a mere geographical change could bring arctic species into the Mediterranean. Here, then, lies the explanation of why the Europeans, following Lyell's English section, include the first glaciation in the Pliocene. The discrepancy between the European usage and that of the Americans, who place the beginning of the Pleistocene at the beginning of the first glaciation, was clearly explained by Dr. W. D. Matthew a year ago at a meeting of the Cordilleran Section of the Geological Society of America. Brooks' has correlated the forest bed at Cromer by means of its temperate flora and mixed Pliocene-Pleistocene vertebrate fauna with the well-known deposit at Tegelen in southeastern Holland. Above the forest bed at Cromer lies a stratum of marine sand with an arctic fauna, and a similar bed is known at Yarmouth. These sands are thought to represent the beginning of the second or Mindel glaciation of Europe. True glacial deposits of this age are now recognized in England and referred to as the chalky boulder clay. They are widely distributed and show that the glaciation was more extensive than the later, better known glaciation. The remains of the older deposits, being overridden in many cases by the younger and largely obscured, are difficult to distinguish. Thus the oldest recognized and most extensive glaciation in Great Britain corresponds to the oldest recognized and most extensive glaciation in Holland and north Germany. Toward the end of this age northern Europe was depressed, and the materials of the well-known chief terrace of the Rhine were deposited, and probably also those of the 130-foot terrace of the Thames. At the beginning of the long interglacial age that followed, the depression of northern Europe continued and the Eem marine beds with a temperate fauna were deposited, forming in places the upper part of the chief terrace of the Rhine. Similar beds occur in Sussex, at Holderness, and other places in England. Everywhere it appears that the 1 Op. cil., p. 311. 68 San Diego Society of Natural History [Memoirs submergence was succeeded rather soon afterwards by uplift, and the marine beds gave place to estuarine and lacustrine deposits, the latter characterized by Corbicula fluminalis, Paludina diluviana, and Bithynia tentaculata. In this interglacial age, which is by far the longest of all, Chellean archaeological remains are found in the lower part and Acheulian in the upper. The third or Riss glaciation of the Alps is represented by the second glaciation of north Germany, Holland, and England. It is the best known glaciation in England. At Holderness, Yorkshire, and in other places in northeastern England the Hessle boulder clay, belonging to this age, is clearly separated by temperate marine sands from the older chalky boulder clay. This glaciation corresponds to the middle group of terraces along the rivers. The cultm-e was Acheulian, giving place to Mousterian. The third interglacial is poorly represented except in northern Germany, where it is recognized at Rixdorf and Phoeben, in borings around Berlin, and at several other places. Remains of temperate mammalian species and of mollusca, the chief of which is Paludina duboisiana, are found. Most of England seems to have been subjected to erosion, but peat beds at Holderness made up of temperate species are assigned to this horizon. The culture was Mousterian. The fourth or Wiirm glaciation is also poorly represented in Great Britain, but it is thought that arctic peat at Holmpton and Pennines in England and arctic peat and small valley glaciers in Scotland represent it. In northern Germany it is well recog- nized, however, as the third glaciation of that region, and by analogy, the low terraces of the Rhine and other rivers are assigned to it. In Switzerland there was a temporary retreat of the ice in the middle of the Wiirm glaciation called the Achen interstadial. The culture was Solutrean and at the close early Magdalenian. During the final retreat of the ice there was a slight readvance, known as the Buhlstadium. In Baltic regions this readvance is also recognized, and the period of retreat preceding it is known as the Baltic interstadial. The retreat of the ice from the southern end of Scandinavia has been carefully studied by De Geer and others in Sweden. By counting the annual varves in the glacial lake deposits, it has been possible to determine with remarkable accuracy the year when the ice edge abandoned each lake, so following the retreat northward. During part of the time, the coasts of northern Europe were slightly submerged and marine deposits are found, first indicating arctic temperatures and then a gradual thermal amelioration culminating in what is known as the chmatic optimum. This older Tapes or Littorina period, as it is called locally in Norway, corresponds to a climatic optimum recognized in nearly all well-known regions of the northern hemisphere. The climate was warm and moist. It was succeeded by a warm dry period, then a cold dry period (sub-boreal period), then a cold wet period (sub- Atlantic period), and finally a somewhat drier period, the present. Comparison of California and European Sections The lower Pliocene beds at Elsmere Canyon, the Jacalitos zone, and corresponding occurrences in other parts of California can be correlated with the Boxstones and Lenham beds of England. In both regions these zones contain faunas indicating warm tempera- tures, including a few species that are more characteristic of the Miocene and that have caused some paleontologists to consider them of Miocene age; but both the faunas are seen to have, when studied in greater detail, a closer relationship with the overlying Volume I Pliocene and Pleistocene Mollusca of California 69 < a a z O 9" c O O M be s o 1-J J2 3 C Co ^ G o c^ a.2 is S --Pi ■"So t. a; C a) o. oj fi o o ;5 hE 3 a is ? C.2 O iU S-2 bH O T C ■c p. o us a ((Bajciaj aurjBj^ §^. o p w Q Pi o h-; w m iz; o I— I < W Di 04 O O z « o b <: O bO a O o 5 S T1.9 = bO-O ■, o a* O o > S ?3 ^ cc C3 c3 <» ir S .2 "bib-*^ C'43 aoU "3 b€ c c S o '-' •2 c S §-S-3 fa *^ Oj sec Oj'm o c 02 - O feH PM r^ ci CJ c" o w CO O 1 a tH 03 o § ■? o z •< z _c M _C3 "bi >> bC o ^■^ c o o o CQ CO o t-i s: fS ♦:> ft C 2 ?= s ^ O 02 to r- cS E oW° & § s =oW^ ■a^-C Co bO o o S & " S *j o c.=i o o » s ° s t- 4Mto o -a O .5-> O 0) p: mo " o w z K O .2 ^ c ^ S C 3 U)03 o ^ H C 5^ C3 '^'bbF S^5 2 t- C .M 3 t. tn 03 oijtt- 03 Q 3 T3 _ S O g £ o-^ C it •S S 3 3 cj O c3 C § ">= >>'S S rt Cj O W o<; Ilii u ■se - O) "3 S.^ e O 3 g C " § S O fc 2 03 o ^ r? bD bO -n c c a u. n 03 o:S fe ■±3 01 O I OJ- — >-^ o OJ a; Osborn, H. F.; "Mammals and Birds of the California Tar Pools," Natural History, N. Y., Vol. 25, pp. 527-543, 1925. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 73 terrace deposits, which seem to be contemporaneous, to the part of the geologic column in which the other kinds of evidence indicate that they would fit the best. Assuredly the processes of deformation, erosion, and subsequent isostatic readjust- ment among the local crustal blocks, all of which apparently preceded the time of the general accumulation of alluvium in California, are processes requiring a considerable amount of time for their completion. It seems improbable that they could have been completed by the end of the Mindel-Riss interglacial ; and therefore it might be well to consider if there is any more likely time for the deposition of the alluvial terrace deposits. The widespread deposition of alluvium indicates depression. The weight of glacial ice is known to have had some effect in depressing continental areas, and investi- gations of the effects of the most recent glaciation in Scandinavia and in eastern North America have shown that after the return of the glacial waters to the oceans there has been a certain amount of lag in the recovery of the continental areas. Hence the time when the continent was downpressed and the oceans full would be the most likely time for a temporary reversal of movement in a region that was being subjected to gradual uplift, and such a time is the end of a glacial age. It is interesting to note that Brooks correlates the terraces of the Rhine, the Thames, and other European rivers (in some of which fossiliferous deposits have been studied) with the ends of glacial ages and the beginnings of interglacial ages. As the climatic indicators of the Rancho La Brea fauna are conflicting, the mammals pointing to cold temperatures and the birds to warm, it would not be unreasonable to suppose that the accumulation of the vertebrate remains continued from the end of the glacial age into the beginning of the succeeding inter- glacial, that many of the animals may have migrated northward while the birds were arriving from the south. Obviously, there is but one place in the correlation table where such conditions are indicated and where the Rancho La Brea fauna and the older alluvium deposits can be placed, the end of the Riss glaciation. It can be further pointed out that after the mid-Pleistocene deformation there have been but two glaciations, and in the various regions of southern California there are but two well-defined sets of alluvial terrace deposits, the younger having an admittedly Recent, postglacial, appearance. The Riss-Wiirm interglacial seems to be an age of continued uplift in California and of local uplift in Europe. European deposits are scarce and non-marine. In the Sierra Nevada the cutting of the inner valleys was continued. Along the coast, marine terraces were developed with remarkable uniformity from San Diego, perhaps from Lower California, to Oregon or farther. The Palos Verdes terrace at San Pedro in the Los Angeles basin and its equivalents along other parts of the coast provide one more definite horizon for correlation. Marine deposits well described by Arnold as the upper San Pedro series indicate that the ocean temperatures were considerably warmer than at present and require that these deposits be assigned to the only interglacial age not already accounted for, that is, the Riss-Wiirm, or last interglacial. For physiographic and other reasons these deposits are too old to be assigned to the post-glacial climatic opti- mum which has been dated by Scandinavian geologists as reaching its maximum in about the j'ear 4100 B. C. In the Palos Verdes deposits there may be one or two im- portant extinct invertebrate species (Cancellaria tritonidea, Cantharus fortis) , and remains of vertebrates belonging to the Rancho La Brea fauna have not infrequently been found. As it is unlikely that so many fossil bones could stand transportation and deposition unless fresh, this latter fact is taken as confirmation of the correlation of the Rancho La Brea fauna with the beginning of this same interglacial age. Furthermore, Dr. Stock states that overlying the terrace at Santa Barbara, which as shown above 74 San Diego Society of Natural History [Memoirs must also be assigned to this interglacial age and may be the exact equivalent of the Palos Verdes, is an asphalt deposit (near Carpinteria) that has yielded remains of some of the Rancho La Brea species. This last deposit must be appreciably younger than the terrace, for time must be allowed for the withdrawal of the sea and the accumulation of the asphalt, but there is nothing in the physical relations to show how much younger it may be. The vertebrates may not have been entrapped until after the last glaciation had begun. The last glaciation saw the ocean nearer the outer edge of the continental shelf, eroding away the broad westward extension of the Palos Verdes terrace, cutting lower terraces that are now submerged, removing the portions of the continental shelf that had been elevated above the general level, and filling in the hollows with the detritus. At the same time the so-called third and fourth glaciations of the Sierra Nevada were taking place. The third and fourth glaciations of the Sierra Nevada are very closely related to each other, being separated only by a comparatively brief retreat, both belonging probably to the fourth or Wiirm glaciation of Switzerland. It is to be noted that a similar brief retreat of the ice took place in the Alps near the middle of the Wiirm glaci- ation, and that in eastern North America the earlier part is called a separate glaciation, the lowan, although it is recognized to be closely related to the later or Wisconsin glaciation. The Alpine retreat is known as the Achen interstadial. During the final retreat of the ice in Europe, several slight readvances took place, the Buhl, Gschnitz, and Daun stadia. It is possible that these or other readvances can be recognized in the divisions of the Wisconsin glaciation of eastern North America, but it is unlikely that they should be represented so far south as the Sierra Nevada. The third and fourth Sierran glaciations are much smaller than the second, the fourth being distinctly less than the third. As hitherto only this last pair has been recognized, it can be under- stood why LeConte, who made most of his study in the Sierra, should have concluded that there was a long division of the Pleistocene preceding the glacial. He has been recently quoted to this effect by Eaton. In the final stages of the ice retreat there occurred in northern Europe minor sub- mergence of the continental borders, upon which were deposited marine shell zones indi- cating at first arctic conditions, later succeeded by less severe and finally by decidedly warm conditions. The same succession is recognized in the peat bogs of various regions; and the time of warmest temperatures, warmer than today, is known as the climatic optimum. So far as known, there is but one time since the last glaciation when the general temperatures were warmer than at present ; and if this horizon could be recognized in California, one more reliable datum plane would be furnished for the post-glacial. So far, this has not been done. Perhaps archeologists have recognized this horizon in their work in Arizona and New Mexico. The annual rings of a single living big tree in the Sierra Nevada should reach two-thirds of the distance back to the climatic opti- mum, for in Antevs' most recent chronology the climatic optimum is dated as having reached its maximum 6000 years ago (0 taken as A. D. 1900). Owens Lake, in eastern California, has been estimated to have overflowed last about 4000 years ago.' Of the post-glacial geologic history of the coast of California we know only that the ocean returned or had returned to approximately its present level, that it may have risen slightly for a brief time during the deposition of the younger alluvial terraces and afterwards sub- 1 Gale. H. S.; "Salines in the Owens. Searles, and Panamint Basins, Southeastern California," U. S. Geol. Survey, Bull. 580-L, pp. 251-323, 1914. see especially pp. 263 and 319. Volume I Pliocene and Pleistocene Mollusca of California 75 Q s 1 1 1 1 < 3 all's o O s 3 -3 t-> 01 ^ s 1 S 1 =*> ■3 s'S 3 "3) 1 -fj a o3 03 .« o3 a m O 2; -23cn 3 m 0) 'S _so aW .(3 13 ■a §.S£ S a o '35 fi 2i 3 3 a; l§ -1 g IS "3 a 3 = g a cj 0 0 ^a a 2 a a 0 .2 "O *3 t-. o-a a •gli 1 1 CO 1 => 1 ■3 bC 3 03 3 3 4J 03 Em a CD a> bO _ ^ > o > « 1 m H a. t» 2*. W s H en S 3 a! £ (D 1 1 .3 1 £ 1 " 1 >> 1 O 5 Z 3 •3 'm 1 C 1 O 1 3 0 3 is "0 O o si .a -2 1 o3 O 3 =" 1 1? 1 lllll 3£? 0 a if a a 03 .2 ^ 11 CO J3 <1 o ^i 3 "^ ■/2 o3-- 03 ^ o fa 1 1 1 1 ^3 o 1 1 o < Q < < a "3 1^ 1 0 H a 02 a a ■ 2.2 l§ 1 S M 1 03 1 ^ — -0 ■= 1 0 H -t^'co a^ a 0 ^ — 0 "3 a .3 03 Pi a H cS " ^ 1 s i ^ |la!| •II o (S 1 H 1 H 0 <^- ffl £ u 1 1 CO CD a 03 z <« < z K O -0 'o § m ° ° n M 03 O Sea c— s .3 "> ^ _3 1 3 .2 1 a o 3 -S 1 1 a .2 g s ^S .3 s- s- r o3 =^ = „ s 0 m 0 a 3 r- l- 03 m bO ill 111 0 2^ oj OJ-O a 0 0 -a 0-, 0) a 0 M +^ a 3 on c3 c2 0 CS] ^ ^^ Si a> 11 < o ^S^ 03 »» '3) CD 55 0 ca 1. 03 OiW " a 03 ^S 03 03 3""' 03 c^ ff-- c^ ^ 0 =^ tfpipc;^- '^ a Q M H 1-5 OJ-S V a a Ml S c =3 1 J3 ^ 0 1 0 1 0 Q (3 0 0 0 0 *"m^ ■:3 S' 2 0 O lO 0^ [ o_ 1 o_ 0 0^ o_ 0 o__ q^ o3 rj c3 O QJ H|"o CO 00~ cT to" , 10" , lO" 0 o~ 0" (N CO "O t^ 10 OJ 00 tn Tjl ^ 0 0 5 a « >< "S ° a, -^ c y 0 1 0 1 0 0 0 0 =3 O =s 0,0,0 0 B'-S j3 lO^ o_ •o_ 1 o_ 1 0 0 0^ 0 0 o_ 0 !§§ oo" '^*" c !N (^^ 1:^ ^ ^ 10 T(t w^"' c^ 1 c^. 1 c^ c— CI 7— c— ^— 76 San Diego Society of Natural History [Memoirs sided, and that the time since the return of the ocean from the low-level stage has suf- ficed to develop a nearly mature shore line along the drowned coast, except in San Fran- cisco Bay where the shores are protected from the wave action of the open ocean. The estimations of the duration of the various glacial and interglacial ages shown in the accompanying table are for the most part hypothetical and only roughly relative. They are based upon Penck and Briickner's estimation of the relative amounts of weathering undergone by the various glacial moraines during each succeeding inter- glacial age, taking the post-glacial as a unit. The post-glacial has been accurately measured by De Geer in Scandinavia, who counted the annual varves deposited in glacial lakes and the similar clay layers in post-glacial fiords. Antevs has given a recent summary of the geochronology of the period since the retreat of the ice from southern Scandinavia.' It is calculated that the ice retreated from southern Sweden about 13,500 years ago and took about 5,000 years to retreat northward, making the post-glacial in northern Sweden only 8,500 years long. At a similar rate it would have taken the ice about 5,000 years to retreat across the Baltic, which means a total of about 18,500 years for the post-Buhl period, corresponding fairly closely to the 16,000 years estimated by Penck and Bruckner from the rate of accumulation of deltas in northern Europe. The Buhl-stadium is estimated as another 4,000 years, which gives a unit of 22,500 years for the post-Wiirm period in central Germany. The Giinz-Mindel interglacial is calculated as three times as long as the post- glacial ; and the Mindel-Riss, which was very long, as twelve times. The figures for the glacial ages are mere guesses, compromises between the opinions expressed by various authors. There may have been numerous withdrawals and readvances of the ice and even whole glacial ages, especially before the Riss and Mindel, that have everywhere been entirely obscured by later more extensive glaciations. In relatively warmer regions, perhaps in the Sierra Nevada, the interglacials must have lasted proportionately longer than is indicated in the table, whereas in colder regions (like Greenland today, for in- stance) they must have been proportionately shorter. However, it is hoped that the estimates will help to give a better perspective to the Pleistocene history. The application of the figures, however rough, may be of some use in giving an approximate idea of the rate at which geologic and evolutionary processes proceed. For instance, they may indicate that marine erosion can reduce an embayed shore line in such rocks as occur along the coast of California to a state approaching maturity within a period of about 20,000 years. However, great caution in drawing such conclusions is advisable. The Rancho La Brea fauna, with all its extinct vertebrate species, appears to be only about 150,000 years old. Whether the La Brea fauna be assigned to the second or to the third interglacial age, it is a mystery inviting speculation why so many species should live through two or three glacial ages and be exterminated in the last.^ 1 Antevs, E.: "On the Late-Glacial and Post-GIaclal History of the Baltic," Geographical Review, \'ol. 12, pp. 602-612, 1922. 2 Since this paper was written a very important series of articles in the form of a symposium on the glacial theory has appeared in the Bulletin of the Geological Society of America, Vol. 40, no. 4, December 31, 1929. The late Cenozoic deformation has been recognized in the Andes by E. W. Berry in an abstract of a paper published in the Journal of the Washington Academy of Sciences, Vol. 20, pp. 69-70, 1930; and a paper by H. Suter in the Centralblatt fiir Mineralogie .... pp. 269-277, 1927, is stated by G. Steinmann in his "Geologic von Peru," p. 254, 1929, to have correlated the ice ages of the Andes with the Mediterranean and the Alps. Another pertinent article, "Cor- relation of Coastal Terraces" by C. W. Cooke, has been published in the Journal of Geology, Vol. 38, pp. 577-589, 1930. Perhaps the most plausible explanation of the cause of glaciation is suggested in H. T. Stetson's article on "Cosmic Clouds" in the Scientific Monthly, pp. 217- 224, September, 1930. Also, since this discussion was written, another, very important work has appeared, — Matthes' "Geologic History of the Yosemite Valley," U. S. Geological Survey, Professional Paper 160, 1930. Matthes mentions (p. 75) some uncertainty in the correlation of the glacial stages of the Yosemite with the stages worked out by Blackwelder on the eastern slope of the Sierra. Obviously, the following attempt to reconcile the history of the Yosemite with the outline of events given in this paper can only be tentative. The development of the broad- valley physiographic stage seems to have begun after the minor Coast Range deformation and the tilting of the Sierra block at the end of the Miocene. It may have proceeded, with various interruptions or set-backs caused by slight renewals of the tilting movements, through a Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 77 Concluding Remarks It is hoped that the outhne given above will make it evident that the available record of the later Cenozoic history of California is one of the most interesting and most instructive chapters in the geologic history of the earth. Many of the sedimentary forma- tions, geologic structures, and physiographic surfaces of California are so young and so well exposed that they can be looked upon almost as huge laboratory experiments in sedimentation, mountain-building, and stratigraphy. Sediments recently deformed and uplifted to places where they can be observed offer opportunities for study that rival the opportunities for studying submarine processes in the present oceans, and in addition illustrate the effects brought about by the geologic processes of deformation and erosion on bodies of such materials. Mountains that were formed but yesterday make much the best subjects for studying orogeny. The readjustments that can be seen to have taken place subsequent to the main period of orogeny have an important bearing on the appli- cation of the theory of isostasy. Of fully as much interest are the remnants of ancient physiographic forms, many of them strikingly fresh and well representative of the sur- faces to which they once belonged; and these physiographic forms become especially important when it is recognized that an understanding of them is necessary for a satis- factory working out of the history of the region and a proper estimation of the significance of the other phenomena. The field of study aiming to bring out the interrelations among the various geologic phenomena of sedimentation, deformation, and erosion, with a quantitative estimate of their age, duration, and magnitude has hardly been touched upon. Pioneer geologists came to California with conceptions based upon the entirely dissimilar conditions of Atlantic regions; and although by taking broad views of the country they were able to recognize many of the important relationships, for which they deserve the highest credit, they did not have sufficient facts at the time to be able to see, in what is now believed to be the proper perspective, the events that have taken place in late geologic time. Later geologists have been busy collecting the facts which are necessary for a comprehensive understanding of the history of the region and for making improvements on the views of the pioneers; but, partly because of the prevailing theory of diversity, considerable part of Pliocene time, through perhaps several million years. Then it appears that minor movements such as preceded the deposition of the Santa Barbara zone along the coast were represented by more tilting of the Sierra block, inaugurating the development of the mountain- valley stage. The mountain-valley stage developed during the Giinz glaciation (not yet recognized in the Sierra), during the first interglacial, during the Mindel glaciation (recognized on the eastern slopes but not in the Yosemite). and perhaps during the early part of the second interglacial, in all some 200,000 years or more. The profile of the Merced River was cut down about 900 feet. Then came the Pleistocene diastrophic revolution, accompanied by much greater tilting of the Sierra block, which inaugurated the cutting of the canyon stage. This lasted probably through most of the long second interglacial, through the Riss glaciation (what is here called the second glaciation of the Sierra, probably the Glacier Point stage of Matthes), and through the last interglacial, in all about 300,000 years or more. The profile of the Merced River was cut down about 1,200 feet, the stream-cutting being assisted probably by the glaciation of the Glacier Point stage. Then came the El Portal stage of glaciation, which seems to correspond to what is here called the third glaciation of the Sierra and perhaps to the lowan glaciation of the eastern states and the early W'ijrm of Europe. According to the correlation table, it ended only about 5.'). 000 years ago. Matthes gives good e\'idence that the succeeding period must have been of considerable duration, but in comparison with the other interglacials it seems to have been short and it may be admissible to call it an interstadial. The stream erosion accomplished during the interval seems to have been very small (Matthes, p. 67). The last or Wisconsin stage of glaciation may have lingered in the Yosemite region until even less than 10,000 years ago, to judge by the freshness of some of the glaciated surfaces. The evidence of two advances during this stage (Matthes, p. CO) suggests that the last maximum may represent the Buhlstadium, the ice at the heads of the glaciers not disappearing until much later. There are even now some small remnants in some of the northeasterly facing cirques. The rate of stream erosion postulated above for the mountain-valley and canyon stages does not seem unreasonable, when it is considered that in the former stage the erosion was working on deeply-weathered materials and that in the latter it was assisted by a much-steepened gradient and by the glaciation of the Glacier Point stage. It is probable that during the development of the broad-valley stage several moun- tain valley forms had been produced and subsequently obliterated beyond any present possibility of recognition. The evidence given by Matthes (pp. 70-73) of the antiquity of the El Portal stage is a much more serious difficulty. If the El Portal ice retreated 55,000 years ago and the Wisconsin ice 10,000 years ago, the glaciated surfaces of the former would have been subjected to weathering only five and a half times as long. For the obliteration of glacial polish on rock surfaces that length of time would, perhaps, be enough, especially as the polish of the last stage has in many places already been obliterated (p. 69). But the pedestals and the aplite dikes cited by Matthes suggest that even wnth a more severe climate during part of the time (during the later glacial stage), the estimated time would be too short. It is probable that the estimates should be revised upward. 78 San Diego Society of Natural History [ Memoirs little has been done toward organizing the local facts that apply to the various more or less isolated districts with a view to fitting them into a related whole. Recently a few writers have taken pains to state that the forces affecting the surface of the earth are so diverse and are so local in their effects that it is practically useless to attempt to visualize the history of a whole region as a unit, and still more futile to attempt inter- regional correlations. And yet it now seems that the study of such problems is already possible. The foregoing discussion is intended to show, if it does nothing else, that a beginning can even now be made. Even if the conclusions hereby arrived at are later partly disproved ^ it is believed that the additional facts brought out to disprove them will merely make the newer views more accurate and that the possibility of making rough correlations and of working out a regional history will not again be questioned. It is hoped that, as far as the later Cenozoic history of California is concerned, the period when geologists could imagine unlimited time and unlimited forces of any nature without regard for the dates and forces recognized in neighboring districts is now passing. There is diversity, of course, diversity in details; but the major movements of the earth's crust seem to have remarkably widespread effects, and their wide distribution should not be denied merely because a satisfactory explanation is not yet found. The correlations proposed above and the outhnes of the geologic history of the various regions considered are now offered as a basis for discussion. It is hoped that they will be corrected and improved upon by other workers. HOYT RODNEY GALE. Los Angeles, California January, 1930 PART II SYSTEMATIC PALEONTOLOGY PART II SYSTEMATIC PALEONTOLOGY Introduction The Mechanics and Accomplishments of Paleontologic Study The study of paleontology has some features in common with open pit mining. A certain amount of work must be done with no direct gain before the material sought can be reached. A certain amount of worthless material must be shoveled up and carted away before the coal or diamonds or other valuable deposit is exposed to be worked. The object of the study of paleontology or of conchology or of any other kind of investi- gation of organic beings is to discover the natures of the various organisms and the relations between them. But before such a study can be carried on successfully, all sorts of incidental problems of no real value in themselves must be settled and got out of the way. In the case of conchological paleontology, the most vexatious part of this worthless overburden is nomenclature and the problems connected with it, which are bound up in ambiguous passages and interpretations of sometimes rare but only moderately ancient writings and in the stupendous voluminousness of modern literature. Difficulties in collecting specimens, of handling them in the laboratory, of examining them under microscopes or under the naked eye, and other physical mechanics are expectable and bearable; but the burden of mastering the literature and of settling nomenclatorial problems is becoming so great that it usurps the larger part of an inves- tigator's time; and unless he watch himself, he will find himself devoting his entire time to it, never reaching the starting point of real accomplishment. Too much work is done merely in the hterature, making more literature out of old literature ; too little attention is paid to actual specimens and almost none to large aggregates of specimens considered in the light of living beings. So much effort is expended on the literature that not enough is left to overcome the normal mechanical difficulties of collecting and handling specimens, and as a result the latter are sadly neglected. It is as if the overburden had become so gi-eat that many pits never reach the valuable deposit through it and in many of them the hole is so small at the bottom that production is confined to a very narrow, limited spot. A thimbleful in the top of the deposit is all that is taken out. The man of large enterprises, who is accustomed to remove mountains with steam shovels, looks once at these paltry details of accomplishment and turns elsewhere for more profitable fields of endeavor. So would the Lamarcks and Linnseuses of today turn away froin systematic conchology and paleontology and devote themselves to physics, medicine, politics, philosophy, business, or in any case to some field where the overburden is at present not abnormally thick. It is hoped for the sake of the conchologist and paleontologist that the present conditions are abnormal. We are in a state of transition from the old system of nomen- clatorial natural selection to the new nomenclature according to fixed rules. Formerly, prior publication was a powerful argument in favor of a name, but the work of a genius like Lamarck was not set aside for a sales catalogue without descriptions because the 82 San Diego Society of Natural History [Memoirs latter had one year's priority. In other words, priority was like brute strength in the animal kingdom and usually prevailed according to the workings of natural selection, but cunning in the one case or wisdom in the other sometimes prevailed and it was hoped that in the end reason would have full sway in both. Now, instead of natural selection, we have an International Commission on Zoological Nomenclature, and we attempt to regulate nomenclature by arbitrary fixed laws. That unexpected and unimaginable difficulties should have arisen in the application of such fixed laws is not surprising, for experience in many fields shows that government by fixed laws has always met with difficulties and in very few cases, if ever, has it succeeded permanently, until the laws themselves could be made adaptable to evolutionary change. Although at present there is less uniformity in usage than at the beginning of the century, so many changes in names having been made recently and so many still being made, it is possible that scientists may in the long run be able to furnish an exception to the general rule against government by fixed laws, and it is to be hoped that their present experiment will finally succeed. In any case, we can feel sure that eventually the transitional period will end. Either there will be a return to natural selection, so that the nomenclature will again be determined by custom and by a preponderance of opinion among the leaders or geniuses of the profession ; or there will be a rigid adherence to the rules of the International Commission and the petty proposers of names will be enthroned, at least for a time, with later, perhaps, a gradual modification of the rules so as not to limit the progress of science. Obviously, uniform usage should be the chief aim of the systematist; and although it might be a matter of opinion which way uniformity can be more easily attained and which way would bring with it le.ss disagreeable features, it is clear that all workers should follow the same plan. At present, the concensus of opinion is strongly in favor of abiding strictly by the rules, and consequently the present writers are doing their part to upset usages and change names to the end that eventually uniformity may be reached. We must play the game, even though it is at times disheartening to see familiar names give place to obscure substitutes. Nomenclature In a number of cases when the time and necessary materials were available, the present writers have attempted to follow a systematic procedure for determining the proper nomenclature. They believe that following this procedure, or something very similar to it, is the only satisfactory method of settling nomenclatorial problems. It has become manifestly unsafe to accept without verification the dictates of nomen- clatorial autocrats, unless it be clearly recognized that the unverified usages are merely makeshift, temporary arrangements. The International Rules or Code of Zoological Nomenclature and the opinions interpreting these rules issued by the International Commission on Zoological Nomenclature must be carefully studied by every worker and must be rigidly adhered to, if our present experiment is to succeed in bringing us appreciably nearer uniformity.' Generic names, including names of genera, subgenera, and sections, and specific names, including names of species, subspecies, and varieties, are treated in nearly the I The International Rules were published in the Proceedings of the Ninth International Congress on Zoology held at Monaco, March. 1913. The opinions, now over a hundred, have been published from time to time by the .Smithsonian Institution as miscellaneous publications (Nos. 1938, 1989. 2013. 2060. 2169, 2256, 2359, 2409, 26,i7. 2747, 2830. 2873. 2973, 3016). the more recent of these numbers being kept together in Volume 73 of the Miscellaneous Collection. In order to make this material more accessible, the rules and summaries of the first ninety opinions were republished in the Proceedings of the Biological Society of Washington, Vol. 39. pp. 75-104, July 30, 1926. Volume I ) PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 83 same manner. Names of both classes depend upon priority, the first name validly published since January 1, 1758, taking precedence. Also, in both classes, the names are anchored to a definite part of the animal kingdom by types, the generic by type species and the specific by type specimens (if preserved). The method of proceeding is as follows: In the case of generic names, a list is made of all the names that have been applied to the familj', or the part of the family under particular consideration, in the order of the dates of earliest publication. Then each name is considered, beginning with the oldest, first to determine if it is available, that is, actually published after January 1, 1758, in a form consistent with the binomial system (or in a binary sense as described technically in the opinions of the International Commission), and not previously used in any other sense in such a way as to invalidate it as a homonym, and afterwards to determine to what part of the family it is anchored by its type species. The determination of the type species is sometimes difficult. If the type is specifi- cally designated in the original description of the genus (type by original designation),' or if but one species is mentioned in the original description (type by monotypy), or if one species cited in the original description has a specific name exactly like the proposed generic name or has in its synonymy a specific name exactly like the proposed generic name (type by absolute tautonymy), the type is thereby definitely fixed and the task is easy. But if the type is not definitely determined by the text of the original description, its designation must be sought in the writings of subsequent authors (type by subsequent designation) . The author must actually use the word type (or its equivalent in a foreign language) to make the designation valid. In the few cases in which generic names have been proposed without species, the first author who assigned species to them should be treated as if he were the original describer, insofar as type designation is concerned. In all cases of type by subsequent designation it is essential to know what species^ were included in the genus by the original describer or by the one who first assigned species to the genus, for only such species are available as types, and designa- tions of other species are not valid, not even designations of recognized synonyms of species in the original list (unless they are technically exact synonyms, based on the same type specimens, such as names published as neiv names for species in the original hst). In the case of generic names definitely proposed as substitutes for older names preoccupied, it is assumed that the new name must take the type that the old name would have had according to the ordinary methods of fixing the type; but the present WTiters believe that if the invalid name is merely listed in the synonymy of the new name, it not being expressly stated that the latter is a neiv name for the former, then the type may be selected either from the list of species cited in the description of the new genus name or from the list of species cited in the original description of the old name referred to (and clearly meant to be included by the author of the new name), according to the ordinary processes of type fixing.' Some of the works in which type designations for molluscan genera are most apt to be found are: ' This includes not only cases where the author states definitely that a certain species is the type, or the genus is typified by a certain species, but also where an author names a new species or renames an old species "iypus" or "typicus" as a specific name (Int. Rules, Art. 30, I,b). ' These species include synonyms mentioned at the time but no synonyms or species referred to questionably. » For further discussion see pp. 48&-487, 512-513. 602-603, 604, 609-610. 84 San Diego Society of Natural History [Memoirs Montfort, Denys de: "Conchyliologie Systematique . . .," Paris, 1810, chiefly gastropods and cephalopods. *Schumacher, C. F.: "Essai d'un Nouveau Systeme des Habitations des Vers Testaces," 1817. UntU the pubhcation of Stewart's paper (1930, listed below), the present wTiters considered as valid type designations only the passages in which Schumacher actually applied the word type to the species cited under a genus. However, Stewart has pointed out that a sentence in Schumacher's Introduc- tion (p. 20) may make a validly designated type of each species cited under a genus in which Schumacher had but one section, for in that case there is but one species under the genus and it appears that Schumacher definitely designated as types the species he cited. As in other cases in which Stewart has discovered authors designating types that the present WTiters did not know of in preparing this catalogue, the reference is preceded by an asterisk (*). *Schmidt, F. C: "Versuch iiber die beste Einrichtung . . . der verschieden Naturkorper . . . , vorziiglich der Conchylien-Sammlungen, . . ." etc., (Gotha), 1818. *Fleming, J.: Article on Conchology in the Supplement to the Encyclopsedia Britanniea, (Edinburgh ?), 1818-19. Fleming, J. : Article on MoUusca in the first American edition of the Edinburgh Encyclopsedea, Philadelphia, 1821. Children, J. G.: "Lamarck's Genera of Shells," Quarterly Journal of Science, Literature, and the Arts, Vol. 14, pp. 64-86, Oct., 1822; pp. 298-322, Jan., 1823; Vol. 15, pp. 23-52, Apr., 1823; pp. 216-258, July, 1823; Vol. 16, pp. 49-79, Oct., 1823; pp. 241-264, Jan., 1824. Fleming, J.: "Molluscous Animals, including Shell Fish; . . ." forming the article "MoUusca" in the Seventh Edition of the Encyclopaedia Britanniea, (Edinburgh), 1837. *.\nton, H. E.: "Verzeichniss der Conchylien," 1838-9. Herrmarmsen, A. N.: "Indicis Generum Malakozoorum," Vol. 1 (A-L), 1846-47; Vol. 2 (M-Z), 1847-49; Sup- plement, 1852. Gray, J. E. : "A List of the Genera of Recent MoUusca, their Synonyma and Types," Proceedings of the Zoological Society of London (Pt. 15) for 1847, pp. 129-219, November, 1847. Woodward, S. P.: "A Manual of the MoUusca," Ed. 1, 1851-56; Ed. 2 (with additions), 1866-68; Supplement to Ed. 2 and Ed. 3, by Tate, R., 1869, 1875. Meek, F. B. : "A Report on the Invertebrate Cretaceous and Tertiary FossUs of the Upper Missouri Country," Hayden Report, U. S. Geological Survey of the Territories, Vol. 9, 1876. Stoliczka, F. : Memoirs of the Geological Survey of India, Paleontologia Indica, Ser. 5, Vol. 2, (Gastropoda), 1867-68; Ser. 6, Vol. 3 (Peleoypoda), 1870-71. Bucquoy, E., Dautzenberg, Ph., and DoUfus, G.: "MoUusques Marins du Roussillon," Vol. 1 (Gastropoda), 1882-1886; Vol. 2 (Pelecypoda), 1887-1898. Cossmann, A. E. M.: Various writings, especiaUy in the series: "Catalogue des CoquiUes Fossiles de I'fiocene des Environs de Paris," Annales de la Society Royale Malacologique de Belgique, Vol. 21, pp. 17-186, pis. 1-8, 1886; Vol. 22, pp. 3-214, pis. 1-8, 1887; Vol. 23, pp. 3-324, pis. 1-12, 1888; Vol. 24, pp. 3-380, pis. 1-12, 1889; Vol. 26, pp. 3-163 (Supplement), pis. 1-3, 1891; Vol. 28, pp. 3-lS (Appen- dix No. 1), 1893; Vol. 31, pp. 3-94 (Appendix No. 2), 1896; Vol. 36, pp. 9-110 (Appendix No. 3), pis. 1-7, 1902; Vol. 41, pp. 186-286 (Appendix No. 4), pis. 7-9, 1907. (The name of the Society was changed to Socicte Royale Zoologique et Malacologique de Belgique, but the Annales were continued in the same series.) Also in the "Essais de Paleoconchologie Compar^e," 13 vols., 1895-1925. Dall, W. H. : Various writings, especially in the Bulletins of the Museum of Comparative Zoology, Harvard CoUege, Vol. 12, pp. 171-318, 1886; Vol. 18, pp. 1-492, 1889; in the Transactions of the Wagner Free Institute of Science (Philadelphia), Vol. 3, 1890-1903; in Professional Paper 59 U. S. Geological Survey, 1909; and in many publications of the Smithsonian Institution; etc.; etc. Harris, G. F.: "Catalogue of the Tertiary MoUusca in the Department of Geology, British Museum (Natural History), Part 1, Australian Tertiary MoUusca," 1897. Suter, H.: Manual of the New Zealand MoUusca (WeUington, N. Z.), 1913. Thiele, J.: "Gastropoda. . ." Wissenschaftliche Ergebnisse der DeutschenTiefsee-Expedition,Vol. 17, pp. 335-382, (Jena), 1925. There are numerous other works, some of which are mentioned by Stewart, in which sporadic designations may be found. In very recent years authors have begun the VoLDME I ] Pliocene and Pleistocene Mollusca of California 85 very commendable practice of stating definitely the manner in which they have found each type to have been established, — notably: Woodring, W. P.: Carnegie Institution of Washington, Publication No. 366 (Pelecypoda), 1925; Publication No. 385 (Gastropoda), 1928. Stewart, R.: Proceedings of the Academy of Natural Sciences of Philadelphia, Vol. 78, pp. 287-447 (Gastro- poda), January 3, 1927; Special Publication No. 3 of the Academy of Natural Sciences of Phila- delphia (Lamellibranchiata), August 9, 1930. Cox, L. R. : "Neogene and Quaternary Mollusca from the Zanzibar Protectorate," Report on the Palaeon- tology of the Zanzibar Protectorate, pp. 13-102, September, 1927. Similar treatment has been given types by Iredale, Marwick, Hedley, and some other modern authors. In the case of specific names, a list is made in chronological order of publication of all the names that have been applied to specimens that fall within the genus or part of the genus under particular investigation. Then the validity of each name is tested as in the case of the generic names, and afterwards the identity of the type specimen is verified. When both classes of names have reached this stage, zoological problems enter in. The type of the oldest valid name must be carefully studied in order to determine to what natural group of forms it is anchored. Then the types of all the other valid names must be taken up one by one in strictly chronological order to determine likewise to what natural group they are anchored. Those that fall within gi-oups to which older valid names have been anchored must become either subordinate names or synonyms. This process requires a large amount of zoological research in addition to numerous references to the literature. In fact, classification should be entirely a zoological problem and the grouping of forms should not be influenced by the accidents of type fixing. Types should be thought of merely as anchors, holding names to particular parts of the animal kingdom; and it should not matter whether a type falls in the center or on the periphery of a group. Classification Nearly every zoologist will agree in principle that classifications should be governed as far as possible by the natural groupings of animals, that every division receiving a name should be composed of closely related forms all descended from the same remote ancestor, and that in most cases the division should contain all the descendants of that ancestor except such forms as have become so radically modified in characters as them- selves to form another whole group of at least the same order of distinctness as the group from which they split. Artificial classifications that group together "for convenience" forms that have noticeable but superficial characters in common and separate closely related forms because of conspicuous but relatively unimportant characters, as well as classifications altered by preconceived artificial boundaries in time and space, are not to be tolerated by those who are working for scientific advancement, except as temporary makeshift arrangements in cases where knowledge is insufficient to give an indication of what the proper arrangement should be. In other words, it is agreed that the final criterion of classification must be phylogeny, — phylogeny, which can only be known from the imperfect paleontologic record and from the inheritance of similar structures from common ancestors, as indicated, not always reliably, by a study of living animals. But even when so much is agreed, differences of opinion must still arise as to the proper size of the various divisions, the most impoi'tant of which are species and genera. 86 San Diego Society of Natural History [Memoirs The species is a more natural unit than the genus. Darwin has shown^ that because of the struggle for existence between the individuals of one species and those of another and between individuals of one variety and those of another the intermediate forms are apt to be squeezed out and exterminated. In its metropolis each form tends to multiply at a rate which would produce many more offspring than could possibly survive, and the greatest factor in keeping down the number of offspring is the competition of other forms. Since the competition is usually most severe between the most closely related forms, closely related species inhabiting adjacent regions or ecologic niches are important factors in limiting each other's distribution and adaptation. When a species is subjected to unusually rigorous competition, as it is when it is in contact with a closely related species, it usually can survive only where it is common. Hence it is, as Darwin explained, that the overlapping of closely related species in geographic distribution and in adaptation to particular ecologic niches usually occurs in comparatively limited zones and the transition from the territory of one species to that of another is in nature usually abrupt. The less common individuals of each species that live in the transition zones are con- tinually being exterminated during adverse times by the combination of their enemies and are continually being replaced by new migrants from the areas in which their species are common. In a simple case a species is an aggregate of individuals living together and bounded in distribution by rather sharp lines. In a living state a species is often a fairly definite unit. The distinctness of species was recognized and oj^eremphasized by the pre-Darwinian naturalists; but in modern times, since evolution has been generally accepted, it has been overlooked or -wnderemphasized. In most cases in nature, closely related species are kept separate either by physical boundaries or by their inability to interbreed. Here is the natural distinction between species and varieties. When varieties are adaptations to conditions that change gradu- ally from one region to another, they will be connected by a broad transition zone of intermediate gradations. When they are adaptations of the individuals of a single species to more or less distinct conditions, they may have more or less distinct char- acters and the transition zones may be narrow, as with species, but through interbreeding numerous individuals will appear with the characters of the varieties mixed. The late Professor W. D. Matthew explained clearly in a paper delivered before a meeting of the Cordilleran Section of the Geological Society of America- that the intergradation and intermingling of the characters of two forms in a series of specimens is usually sufficient proof that the forms are varieties instead of species. Such a case is well illustrated by the varieties and variations of Pecten purpuratus in southern California and Lower California. It is obvious enough, when considered, that it is useless to try to give specific names to all the combinations of characters produced in individuals by the intercrossing of varieties which freely interbreed in nature, for the number of such combinations may reach the hundreds, and the natural facts would be obscured thereby instead of elucidated. It may sometimes be of value to name the outstanding forms as varieties, for varieties are expected to have intermediate variations, and specimens of intermediate characters would then have a place in the classification so that collectors and museum curators need not be faced by the alternative of throwing them away or naming them new species. It is to be presumed that as a result of the geographic changes that have taken place in the past, physical barriers which once separated closely related species capable of inter- 1 "Origin of .Species." particularly Chapters 3, 4, 6. 2 Part of this paper has since been printed in the Bull. Geol. Soc. Amer., Vol. 41, pp. 271-274. 1930. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 87 breeding have sometimes been removed and have allowed the species to mingle and inter- cross freely. In time, paleontologists may be able to point to well authenticated examples of such situations, especially after the migi-ations of the past have been more carefully studied ; but it is probable that such situations have occurred rarely and have not greatly influenced the course of evolution. In such cases paleontologists would mistake the two constituent species for intergrading and intermingling varieties; and in reality they should probably be considered so, for in time they would from interbreeding fuse into a single species, with modified characters. Thus in the living fauna, the magnitude of the group of individuals to which a specific name should be applied is determined b}' the boundaries of the group of individuals that are, or in special cases have been, freely interbreeding in a natural state. Some difficulty may occur in dealing with forms dis- tributed along a long coast line. Forms extending perhaps from the tropics to the arctic and varying slightly from place to place may change accumulatively to such an extent that the extremes are very different in characters and perhaps could not interbreed. Even in such cases, however, the specific unit seems to cover best the whole series, for each variety would breed and intergrade with the one next to it. When the paleontologic record is also taken into consideration the problem of deter- mining the size of the specific unit becomes somewhat more complex, though, as the present writers believe, not seriously so. Since the doctrine of evolution has become the basis of reasoning about such matters, it has often been said that if our records were complete every species could be traced back through its ancestry and be shown to intergrade ultimately with the ancestors of every other closely related species, that any two closely related species must have intergraded at some time, if they do not now do so. But although this proposition is true, it need not seriously impair our conception of a species as a natural unit. As has been pointed out by Darwin, H. S. Williams, ^ and others, evolution does not take place at a uniform rate but proceeds most rapidly at times when physical changes in the environment upset the equilibrium of a fauna. Such changes are the results of diastrophic revolutions, marked climatic revolutions, breaking of geographic boundaries in various ways, and lesser movements of similar natures such as commonly cause the division of sedimentary deposits into formations. "It is a more important consideration, leading to the same result, as lately insisted on by Dr. Falconer, namely, that the period during which each species underwent modification; though long as measured by years, was probably short in comparison with that during which it remained without undergoing any change."- It was mentioned in part 1 of the present paper that as the cold wave of the first glacial age was approaching at the end of the Pliocene a large number of common species, as well as rarer ones, became extinct during a comparatively short time. The faunal readjustment that took place then is surely of the sort in which new species would be formed; and it is safe to say that in California (and probably everywhere) equilibrium was again reached before the elapse of more than one-twentieth of all subsequent time, during which the faunal equilibria have not again been similarly upset. Probably the principal part of the development of each single new species took place in a comparatively much shorter time than that. Hence, if the development of new species begins locally, is confined to a comparatively few individuals, and proceeds rapidly so that the parent species and all the intermediate variations are exterminated quickly, the finding of specimens of intermediate characters should be very unusual. » Bull. 210. U. S. Geol. Survey. ' Darwin, "Origin of Species," Chapter 10. 88 San Diego Society of Natural History [Memoirs Thus in the vertical, or time, scale as well as in the horizontal, or geographic dis- tribution, scale, the transition from species to species is comparatively abrupt, and the species remains a natural unit. Although there necessarily are and always will be differences of opinion about certain forms, whether they should be called species or varieties, it is in many cases because the facts about these forms are not well enough known to show which they are. In the majority of cases the natural units can and will be recognized and so can be used as standards of comparison for the more imperfectly known forms. The genus, on the other hand, is usually an artificial unit, created for the con- venience of classification. The average size of the groups to which generic names are to be applied should be determined with the object of making generic names of the greatest use and the least trouble possible. The ideal size must be somewhere between two definite extremes, though the happy medium must always be a matter of personal opinion. No one worker should say that another is wrong if he extends his genera ever so far or if he confines them to ever so limited an application, so long as he does not bring them very close to either of the two extremes. Also, the tendency of the day should not be pointed to as authority for enforcing one opinion over another, for, to judge from the past, the "more advanced and more progressive" workers of twenty-five years from now are almost sure to be following a tendency or drift in another direction. There- fore, to approach the ideal and reach a state of comparative stability, each individual should base his opinion about the proper average size of genera upon what in his best judgment is the most convenient size for everyone concerned. One extreme is the old Linnsean policy of classing the whole of the mollusca under a score or two of genera; the other extreme is to have a genus for every species. There is something to be said for the former extreme, for a few names are easy to remember and to use and they divide the class into groups each of which is easier to handle as a unit than the whole class. Nothing can be said in favor of the latter extreme, for it is the equivalent of discarding generic names altogether and making specific names twice as long and more than twice as hard to handle. The Linnaean system was meant to be binomial, and to be most useful the generic name was meant to be markedly different in breadth of application from the specific. Even a generic name for every well-marked species is almost obviously too close to the more unreasonable of the two extremes, for it makes the nonfienclature too cumbersome, with too many names, all apt to be involved in nomenclatorial, time-wasting difficulties. Besides, the genera are needed for showing broader relationships, and the unit of the well-marked species and its close or doubtfully distinct relatives can be handled more satisfactorily in other ways. Although there is something to be said for the Linnaean policy of having a very small number of genera, no one now advocates a return to that policy, for a larger number of names is now known to be more useful; but on the whole it appears to the present writers better to err in this direction than in the other, better to construe genera too broadly than to limit them too much to details. The systematist should hold constantly in mind that his names and classification are to be used by workers in other branches of his science or even in other sciences. When every systematist specializing in the minute details of classifying a very small part of the organic world thinks it useful to introduce a myriad of new names, which in most cases he cannot himself remember, and then virtually forces them on the rest of the scientific world by making them of generic rank, he greatly hampers the geneticist, the embryologist, the medical student, the geologist, and others in their work, for other scientists are usually interested chiefly in the definite Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 89 or specific name of the thing they have and in its general relationships to the rest of its class as indicated by its generic name used in a broad sense. A generic name that does not meet these recjuirements is a nuisance to these other scientists, and one that attempts to tell other things instead is an unnecessary burden. A strange argument has recently been put forth to justify creating many new generic names and confining the older we'1-known names to small insignificant gi'oups of species, namely, that as the older names are usually of doubtful nomenclatorial status and their exact application is often subject to change, fewer species will be involved in the changes. In other words, it is suggested to make the unwelcome changes now to avoid the possibility of having to make them later. It might be noted here that if genera are used in a broad sense, such changes will usually mean merely a rearrangement of subgenera. Another argument to justify creating new generic names and limiting old ones is that the inclusion of various species in a genus should indicate that they are fairly closely related, whereas we often do not know whether they are or not, except that they appear to have a number of characters in common. If genera were smaller there would be less risk of including heterogeneous elements. However, if there were no genera, there would be still less risk, so the problem falls back again on the principle of the convenience of taking some risks in order to express relationships still imperfectly known, and the amount of risk that should be taken must be governed by the special circumstances of each case. It is a true, though very unfortunate circumstance that arguments in justification of a multiplication of names are too often merely a form of ratiocination engendered, usually subconsciously, by a desire for the supposed glory of being the author of the new names. During times when the multiplication of names is popular, many writers indulge in it as a sort of speculation not unlike speculative inflation of the stock market, and the process keeps on until the market is glutted with such securities and deflation and hard times ensue, if not a nomenclatorial panic, followed by a gradual return to a more reasonable intermediate position. Such fluctuations are costly in wasted energy, and it is better for science not to speculate too much in this way. A compromise can be reached to combine the advantages of having numerous small divisions and the advantages of having larger, broadly-construed genera, without intro- ducing any important disadvantages of either. It is to be found in the use of subgenera and sections. The genus name is the real name, according to the binomial system, and if there are comparatively few generic names, many workers, including the systematist, can afford to learn them by heart and speak and think of them familiarly. In most cases, the simple generic name coupled with the specific is all that is necessary in dis- cursive references, in faunal lists, and in articles reporting on detailed studies of specific organisms made by those who are not systematists. With many more names, even the systematist cannot learn them and is forced to work on paper. Working on paper, there is no real disadvantage in having quinquenomials (genus, subgenus, section, species, variety), especially as the section need never be used except in a heading or by itself in referring to its group of species collectively, and even the subgenus can be treated that way if desired. It might be mentioned here that at least one of the present writers believes that in place of the sectional name a more desirable form of terminology would be "group of species so and so," as, for example, the "group of Pecten gibhus" for Plagioc- tenium. Sectional names are the names referred to above as ultimately to apply to every well-marked species and its group of closely related or doubtful species. The group and species designation has the advantage of being free from ancient nomenclatorial entangle- ments and of being more flexible and adaptable to the growing needs of science. Perhaps 90 San Diego Society of Natural History [ Memoirs in a few cases both the sectional and the group designations could be used to advantage ; but as employed in this paper and in most conchological works most sections mean no more than the group of tliis or that species. Variation Most of the foregoing and some of what is to come bears on the subject of nomen- clatorial policy, which, after all, is of small importance compared with the zoological problem of determining the relations between organisms. Nomenclature is being dealt with at length here only because it is a necessary means of expressing organic relation- ships and is at present causing an unusual amount of trouble. It is not surprising that elementary students and many of those who make conchology a hobby, collecting shells as boys collect stamps, should never see or should at most times lose sight of the impor- tance of organic relationships; but it is unfortunate that those who have assumed the role of leadership in conchology for the past thirty years have devoted themselves chiefly to nomenclature, to the description of new species and new genera, with scarcely ever a mention of relationships, of variation, of phylogeny, of migrations, or similar subjects. There are hopeful signs in the most recent publications that a change of attitude is taking place. Much data has been collected, but the most important work of organizing it, interpreting it, and digesting it has been left undone. The most interesting fields of endeavor have been touched upon by some of the older wTiters but by only a few modern workers, and these fields stand open now to everyone with opportunities for real accom- plishment. There is no molluscan species that does not vary in characters. Every year the Zoological Record publishes a small hst of articles that describe the variations of a few species, but the number of variations that have been described is insignificant compared to the number that exist. It is important to be fjyniliar with what has already been written on the subject; but it is still more important that students of mollusca should attempt to find out the extent and the limits of variation of the forms with which they work. Some species vary little, others much. Darwin has shown' that the wide-ranging, much-diffused, and common species vary most, especially the species .of the larger genera, that is of genera that are themselves made up of many species. The many species represent many varying forms of the parent radical and bear witness of an inherent tendency in the lineage to vary and progress and become dominant. The most striking contradiction to this natural rule is to be found in the fauna, as described, of small gastropods living off the western coast of North America. A number of genera are said to include hundreds of species, and yet these species are said to be without apparent variation. The species are separated by such fine distinctions that the smallest amount of variation would make one species into another or into a new species. In some cases the addition of one niore spiral line to the shell (plain variation could hardly add less than one at a time) places a shell in another species. As many of the species have been described from and are still known from only one or two speci- mens, it is clear that variation has not been taken account of. Whereas it may be true that specimens may be comparatively constant in noticeable characters if collected from the same locality or from nearby localities of very similar ecologic conditions, it is almost certain that under somewhat different conditions variations will appear that do not represent distinct species. The genus Lora may serve as an example. It is certain 1 "Origin of Species," Chapter 2. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 91 that some species such as L. viridula and L. turricula have a large assortment of varieties and variations. Of the small collection of specimens representing some of the rarer species that the present writers had access to, few specimens, if any, conform exactly with the original description and figure of their species. Some are so distinctly intermediate between described forms that it was difficult to name them, and even the author of the majority of the species, who had identified a number of the specimens, did not always place them with the forms that they most closely resembled. There is no doubt that many names of species in Lora and other genera need to be synonymized as representing individual variations or should be reduced to varietal rank; and the present writers suspect that in extreme cases as many as twenty-five or fifty named forms should fall within the limits of variation of one natural species. When nearly every new specimen is as distinct as a "new species," and when many closely related species are reported living together, either there is something wrong with the treatment of the group or else there is something peculiar about the conditions under wliich the many species live, an explanation of which would be very enlightening. The treatment given Lora in the present paper is based on insufficient material and necessarily includes a number of errors. It is designed chiefly to classify the species already described so that it will be possible to identify specimens with a full knowledge of all the names that have been applied to similar forms. Although some of the synonymy may be incorrect, it is prob- able that still more names should be reduced in rank; the number of natural species is probably less, possibly much less than the number recognized. That is, not too many names have been synonymized, though in some cases, through lack of knowledge, the wrong ones may have been brought together. Paleontologists are usually and Recent conchologists are often handicapped by the lack of a series of specimens sufficient to show what the natural units are. When this is the case, it is often said that it is better to name too many species than too few, or if the species have already been named, it is better to recognize too many than to synony- mize some that should remain distinct. How often this argument is prompted sub- consciously by a desire to be the author of new species, it is hard to say; but it is certain that it is in part fallacious. The reason advanced is that if two or more true species are classed as one, their records become mixed, to the great detriment of science, whereas if two variations of one species are kept separate no harm is done except the multipli- cation of labor in handling more names. However, the fact is that both errors are incorrect, and the present WTiters believe that one error should be as zealously avoided as the other. In actual practice, it happens that when two species are so similar that someone is tempted to synonymize them and are so imperfectly known that the basis of their separation has not been discovered, misidentifications are almost certain to mix the records. It often happens that some workers know of and consider only one of the names, whereas others know of and consider only the other, each identifying all his specimens as the species that has been called to his attention. In many cases the sep- aration is made on the wrong basis, all Miocene species being assigned to one and all Pliocene to the other, or all northern California specimens to one and all southern Cali- fornia to the other, all with a weathered surface to one and all with a well-preserved surface to the other, or all with some conspicuous but inconsequential character to one and all without it to the other. Thus if the records of species easily confused are already mixed (and even where they are not it is often difficult to be sure that they are not), the separation gives a false sense of accuracy and the union of the two mixed records will be actually less misleading and to that extent beneficial. Careful workers realize 92 San Diego Society of Natural History [Memoirs that they must verify the records of specific distribution wherever possible. A frank admission that the true basis of separation is still unknown, as expressed in synonymizing a name, may have the further beneficial result of stimulating someone else with better material to discover and express the basis of distinction. On the other hand, if the two forms do not belong to distinct species, but are merely individual variations or varieties of little significance, much actual harm is done by keeping them separate artificially. Records of distribution are mutilated so that in the case of fossils geologists cannot make correlations with them, paleontologists cannot trace migrations or work out paleo- geography correctly with them, and in the case of Recent shells ecologists and others are deprived of half the information available. Also, the classification is cluttered up with superfluous names and confused so that misidentifications are favored, and workers spend so much time and labor in trying to make separations which are of no value that the progress of science is seriously retarded. Therefore, when the tendency of the time is to create too many names, when descriptions are scattered in many places so that some are not known and comparisons are infrequent, when the classification has become so complex and indefinite that misidentifications are common, then it is better to try to bring the whole together and arrange it in logical order, synonymizing where no significant distinctions appear. To preserve names without logical distinctions, to say nothing of adding more names, would under such conditions help the confusion little. On the other hand, if the classification has been simplified and arranged in a logical order so that the distinctions already made are clear and the general tendency is to compress the species to too small a number, then it is better to examine the species carefully and attempt to find valid bases for making further distinctions. In other words, it does more good and less harm to run the risk of erring on the side away from whatever may be the popular tendency of the time and place. It is unsafe, then, to gen- eralize that it is better to multiply names than to diminish their number. It is sometimes better to run risks in synonymizing, and the present writers believe that now is a time when more synonymizing is needed than is done even in the present paper. Here also a compromise to the advantage of both sides can be made between those who believe in increasing names and those who believe in diminishing them. Well- marked species can be allowed the specific name, and studies of correlation, etc., can be made on the basis of the specific name, while the doubtfully distinct forms can be classed as varieties to retain whatever may be of value in their separate records. In this way the specific unit can be kept together and be made use of, while everything of value in the varieties will eventually appear, and misidentifications will be avoided because the close relationships will be evident to everyone and will receive proper consideration. Doubtfully distinct forms are seldom of any value in making correlations, for they are too unreliable; and when they have varietal standing only, there is less temptation to make unwarranted use of them. Because so much emphasis is laid in the present paper on the study of variation and the broad construction of species as well as of genera (the natural specific units not always being determined by the facts available), it should not be supposed that the present writers would advocate overlooking a real distinction merely because it is a small one. Fine distinctions, no matter how hard to recognize and follow, should be as much respected as the larger, more striking differences, if it can be shown or if there is good reason to believe that they are truly of genetic significance. The practice that should be discouraged is the guessing that this or that difference is great enough to warrant creating a new species or retaining an old one when a knowledge of the vari- Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 93 ations of the form under consideration would in many cases show that its characters intergi'ade and intermingle with the characters of some species already named or of earlier date and that it is therefore only an individual variant. A conception of a species as an aggregate of many individual organisms living together and passing on to their descendants many different combinations of variable characters, all more or less affected by habitat, leads to a study of as large a series of specimens as is available. Such a study will usually reveal the natural relations and show whether a proposed distinction, either fine or coarse, is of genetic significance or not. As specific characters vary within species, so do generic characters vary among the different species of a genus. But, whereas specific variants are separated by certain physical conditions from variants of other species, generic variants often intergrade, sometimes completely and in many cases with numerous other genera. In the absence of good paleontological records in the older formations and when it is difficult to get evidence of phylogeny from a study of the early growth stages, the intergradation of generic characters in species is the best index to generic relationships and phylogeny. All generic characters are subject to variation, and in most cases classifications based upon single characters prove inapplicable to the whole of a complex group. The Tur- ridoe furnish a good example. The better known the different characters become, the more their variation is recognized. Shell characters are believed to be very variable, for they are the easiest to see and learn about. The radulse, opercula, and nuclei are thought to be less variable, in part at least, because they are harder to study and are therefore less well known. Darwin concluded^ that no one character can be relied upon always to show the proper relationships, for now one and now another will be affected by adaptation; but the best classifications are based on affinities in many characters considered together. Hence it is that the relations of species and the intergradation of their generic characters are the most useful criteria for indicating the relationships of the genera to which the species belong. Migration of Species A number of striking specific similarities between California species and corre- sponding forms in Japan, eastern United States, Europe, and Africa were run upon accidentally in the preparation of this paper, and these few instances indicate the exis- tence of many more of the same sort. The older wTiters such as Carpenter and Conrad were well aware of such similarities in various species, though the limited amount of information available to them was not enough to show definitely the significance of the occurrences. Conrad surmised correctly that the presence of a form related to Pecten jeffersonius indicated the Miocene age of a CaUfornia fauna. J. P. Smith has recognized the migration of faunal elements between the Atlantic and the Pacific in Eocene and Miocene times and also between Japan and the west coast of North America.- Ralph Arnold, T. W. Vaughan, and others have also noted migrations, ^ and many writers have recognized the fact of circumpolar migration of cold-water species in comparatively re- cent times. Mrs. I. S. Oldroyd and Miss Lydia Bowen are now preparing lists of analo- ^ "Origin of Species," Chapter 14. ' "Periodic Migration between the Asiatic and American Coasts of the Pacific Ocean," Amer. Journ. Sci., Ser. 4, Vol. 17, pp. 217-233, 1904. "Ancient Portals of the Earth," Pop. Sci. Mo., Vol. 80, pp. 393-399, 1912. "Climatic Relations of the Tertiary and Quaternary Faunas of the California Region," Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, pp. 123-173, 1919. s Dickerson, R. E.: "Ancient Panama Canals," Proc. Calif. Acad. Sci.. Ser. 4, Vol. 7, pp. 197-203, 1917. Davies, A. M.: "Faunal Migrations since the Cretaceous Period," Proc. Geologists' Assn., Vol. 40, pp. 307-327, 1929. 94 San Diego Society of Natural History [Memoirs gous species from Africa, the Caribbean, and the Pacific coast of North America. G. D. Hanna and more recently W. P. Woodring have noted the migration of specific stocks between California and the Caribbean in the Miocene. However, some of these writers have been content with generalities and have not carried these generalities to logical conclusions, and those who have traced individual species or specific stocks from one region to another have only begun the work of bringing to light the many facts that can be discovered about these migrations. The idea of the provincial isolation of the California faunas in the present and the past has been altogether too prevalent among modern workers. It has become almost axiomatic that no California form can belong to the same species as any form from another region, no matter how much alike the two may be in characters, just as it used to be argued that no fossil species could be the same as a living species. Wide-ranging species are given new local names for this reason alone. As a gambling principle for those who want to be the authors of new names, this proposition is a good one, for often some fine distinction can be found to separate the two forms and the new names will be validated ; but as a scientific principle it is not a good one. Nearly all writers (except a few impossible extremists in Australia and New Zealand) recognize the presence of genera, subgenera, and sometimes even sections in different regions. The presence of one genus in two regions means that at some time conditions were sufficiently favorable for the migration of individuals belonging to that genus from one region to the other. Probably one individual could travel only a small part of the distance, but if living conditions were favorable, his descendants would each go a little way until at last the species would reach the other region, unless, perchance, it should have evolved by that time into another species. If the individuals of one genus are sufficiently adaptable or sufficiently hardy to make the journey, it is not unlikely that the individuals of some other genera could make the journey also. In cases where many genera are known to have passed from one region to another, especially if some of the genera are not particularly hardy or adaptable, there is good reason to believe that conditions were fairly favorable all along the way and that some of the more hardy and versatile species might make the journey without losing their specific identity. Because a species is a much more limited and more definite unit than a genus, these cases of the migration of species or of specific stocks (sections or groups of closely-related and doubtful species) provide the most accurate evidence for determining the exact nature and times of the interregional migrations. The distribution of faunal provinces has in the past been very different from what it is now. In the Paleozoic and the Mesozoic, boundaries were fewer and the world was sometimes divided into only two or three great faunal provinces; perhaps once or twice there was only one great faunal community. In the Eocene, what boundaries there may have been did not keep the Venericardia plait icosta fauna from appearing in nearly every part of the world. It makes little difference whether the varieties of the best- known species or specific stock of that fauna are disguised under many new specific or pseudospecific names or not, except that it does disguise them, obscuring relationships. Perhaps the present tendency to dismember V. planicosta is only a fad and will pass away as not in accord with the facts. Perhaps it is correct and will have to be put up with. In the Miocene there was another period of widespread migration. The com- munication between the various regions may have been as easy then as it had been in the Eocene, but the Miocene period of easy communication has not been so well recog- nized because the local representatives of each wide-ranging specific stock have been Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 95 known under local names and their relationships have seldom been noticed. No one species, like V. planicosta, has been called by the same name in many different regions. Since the Miocene there has been no similar, nearly universal intermigration of warm and temperate faunas. As the last of these periods, the Miocene is particularly important. Temperatures were more nearly uniform then than now. Passages into the Arctic appear to have been closed at least part of the time and the waters of the northern Pacific and northern Atlantic were protected from Arctic currents. Species that are now confined by tem- perature conditions to certain latitudes could then range much farther north and south and could pass east and west around the ends of the oceans. Furthermore, there were one or more connections between the Atlantic and the Pacific, one probably through Mexico and others farther south, to say nothing of possible channels through the Old World. In a broad sense, the Miocene coast lines can be thought of as chiefly east and west in contrast to the present north and south arrangement, and the whole temperate and warm-temperate zone of the northern hemisphere can be thought of as a single province, divided into subprovinces, perhaps, but the divisions no more distinct than subprovinces are today. Some waiters state that the connection between the Japanese region and North America was formed at an earlier time or a later time, or both, than the other connections; but even if this is so, the migrations would still have been possible. The Pectens are one of the best illustrations of these interregional migrations, for they are a versatile and dominant group, able to adapt themselves to a wide range of conditions; and many of them are capable of rapid locomotion, moving sometimes as much as several miles a day. Pecten hu7nphreysii of Maryland, New Jersey, etc., Pecten laqueatus of Japan, and Pecten aletes of Lower California, whether one species or three, bear witness of a migration between the western coast of the Atlantic and Japan, prob- ably through California. The present writers do not know the antiquity of this stock in Japan, and it is possible that the last lap of the journey was made from California to Japan in the Pliocene, though there is no evidence of it. It seems more probable that the migration took place entirely in the Miocene, the stock surviving in the Orient until the present day, in Low'er California perhaps to the Pliocene, and in eastern United States apparently not outlasting the Miocene. In either case, the presence of the three forms in the three regions is incontestible proof of the migration. Similarly Pecten (Amusium) jajponicus of Japan and P. vwrtoni of the Atlantic states Miocene appear to indicate Miocene migration between the two regions, though this case is not so certain. The Chinese Pecten (Amusium) laurentii has been reported in the California Miocene under what is probably an erroneous name; and Pecten {Amusium) pleuronectes of China and the East Indies is probably the same as lompocensis of the California Miocene and cristatus Brown of the Italian Miocene. The last occurrence suggests that some of the migrations may have been by the way of Europe. The California upper Miocene Pecten discus may differ in minor respects from the European living and fossil P. opercularis; but it is just as sure an index of migration between the two regions. Similarly, the Pecten swiftii group, fossil and Recent in Japan and Miocene and Pliocene in California, is a certain index of migration to or from the Orient. There are many examples of species migrating between the Caribbean and California, a notable case among the Pectens being shown by P. ziczac of the Caribbean and P. keepi of the California and Lower California Pliocene (or Miocene ?). Another case of unquestionable Miocene migration between the Atlantic states and California is furnished by the Lyropecten, P. jeffersonius and its varieties or relatives. Large forms 96 San Diego Society of Natural History [Memoirs like the LjTopectens are known in Europe and other parts of the world and characterize the Miocene of certain latitudes. Another form of particular interest is Pecten gibbus, which appears to have originated in the Miocene of the Caribbean and is still living practically unchanged and in great abundance on both sides of North America. But the Pectens are not the only group that furnishes examples of these migrations. The strange Corbula gibbiformis of the California Pliocene has so many of the peculiar characters of the European C. gibba that there can be little question about its close relationship, if indeed the two are not specifically identical. The stock must have migrated between the two regions in the Miocene, surviving in California only until the end of the Pliocene but in Europe lasting until the present day. Similarly Mactra orthomorpha of the California Pliocene is practically identical with Mactra stuUorum of Europe. The California Miocene variety longior of the Atlantic living Anatina (Raeta) plicatella is likewise an example of transcontinental migration. Another Mactroid group, MadreUa, is represented in the living faunas of both coasts of Mexico and Central America by two forms (species, varieties, or variations) which must have lived through practically unchanged on both sides of the continent since the Miocene. Similarly, Divaricella dentata of the Atlantic and eburnea of the Pacific have become only varietally distinct. Lucina {Miltha) xantusi, Miocene to Recent of California and the Gulf of California, has long been confused with the Brazilian L. childrencB (of which the present writers have not seen authentic specimens), and to judge from what has been said of these two forms they must have belonged to the same stock in the Miocene and may even yet be the same species. Nucula (Acila) gettysburgensis from the Oligocene of western North America is represented by a very similar form in the Miocene of the Panama Canal Zone and by nearly identical living Oriental forms. Similar ex- amples among the gastropods have not been noticed by the present writers because during the preparation of the gastropod part of this paper time was becoming limited and they were not able to peruse the literature of other regions. Undoubtedly as many examples could be found among the gastropods. The living Psephcea prevostiana of the Japanese region is represented in the Miocene and Pliocene of the Pacific coast of North America by the variety oregonensis, which is so nearly identical in form that it is difficult to find an excuse for retaining it as a variety. Ranella dilleri from the Miocene of Oregon is almost identical with R. gigantea, the type of the genus, living in the Mediterranean. It is possible that the Psephwa migrated between North America and Japan as late as the Pliocene, for at that time also there seems to have been a connection between Asia and North America. The same may be true of some of the other species mentioned and also of some of the Patinopectens. Pecten yessoensis of Japan, though now probably specifically distinct, is so clearly related to P. caurinus, (? Miocene or) Pliocene to Recent, of North America that it must have sprung from the same stock. Perhaps the somewhat cold-water adaptation of the Patinopectens facilitated this migration in the Pliocene. Even during the interglacial ages of the Pleistocene migration of warm-water species between North America and Asia may have been possible, and some species of Haliotis may have passed across at those times. With the change in climatic conditions at the end of the Pliocene, the warm-water species retreated to comparatively isolated faunal pockets or provinces as we know them today, bounded by climatic and continental barriers. Then the cold-water species of the Arctic migrated down the shores of both oceans and found their way even farther south in deep water. Hence many genera and identical species have appeared in the north Atlantic and in the north Pacific, including species of Astarte, Mya, Nuculana, Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 97 Saxicava, Thyasira, Buccinum, Nucella, Lora and other cold-water Turrids, and many others. Presumably there had been earlier opportunities for some of these species to make the journey around through the Arctic, for some are known to have lived in both oceans before the end of the Pliocene. Perhaps they did not have to wait until the end of the Pliocene to start the migration. Perhaps a few species got around in the Miocene or Oligocene through temporary breaks in the barriers. The Myas are well known throughout the California Pliocene, though they become more common near the end, and they are also known in the Miocene. Madra (Spisula) polynyma of the Atlantic is represented in the California Pliocene and north Pacific Recent by the variety voyi, which probably migrated via the northern route. Some California Pliocene specimens of Siliqua greatly resemble the Atlantic living Siliqua nahantensis. Migrations of this sort may be still going on. Here the question of nomenclature must come up again. How far should these migrating forms be recognized and called by the same names? The answer is, of course, a matter of personal opinion. A species that has comparatively recently migrated through the Arctic and appeared on both sides of the Atlantic and on both sides of the Pacific and is still connected by representatives at intermediate points must of course be kept under a single name, provided no appreciable evolutionary changes have taken place during its migrations. On the same principle, a Miocene warm-water species that was at one time in the process of extending its distribution from what is now one region to what is now another, making a journey that in many cases was no harder than the journey today around Florida from the Atlantic to the Gulf of Mexico, should be kept under a single name, unless there is evidence that appreciable evolutionary changes took place. The latter proposition is more difficult to apply than the former, and it has hardly ever been tried, for there are very few paleontologists who know enough of the literature of two regions to be able to do it. However, the present writers believe that it is the more scientific course and is worth while to try. For southern species, the migration between the Atlantic and the Pacific through Mexico or Central America was surely an easy matter in Miocene times and could be accomplished by many species without undergoing any marked changes in characters. At that time it was not inter- regional migration, but migration within a single province. Furthermore, it is usually agreed that a Miocene species which has survived in one region until the present without appreciable change should be known as a single species. Hence, if a Miocene form should survive in two regions without appreciable change, it should still be known by the same name in both regions, even though the regions are not at present connected. There are more such cases than are usually suspected. Finally, if the individuals in one region differ from those in another by a very small amount, such as may be merely a temporary reaction to certain environmental conditions (as individuals in one cove differ from those in another along a single shore line), and the difference appear to be not genetic but of the sort that would disappear in a few generations if the particular conditions causing it were removed, then the form could be recognized as a variety of the parent species. The last case appears to be illustrated by Peclen gibbus and its variety circularis. Surely it is an advantage to spread scientific knowledge from one region to another. It is an advantage to call a species by the same name in two regions^ if it can be done without violating the principles of classification or the natural facts, for by doing so you call to mind through the use of the name the whole interesting and significant background of the specific history besides reducing the number of isolated facts that every worker must deal with. There is no advantage whatsoever in making 98 San Diego Society or Natural History [ Memoirs artificial boundaries, and doing so is apt in the end to cause considerable trouble at the points where the separations are made. Of course in changing established usages it is worth while to be conservative, and in introducing names from other regions to wait until the evidence points clearly to the truth of the history that is implied by the pro- posed change; but on the whole the writers believe that specimens and species should be studied objectively without interposing any preconceived barriers in time or space. In that way only will many unsuspected important relationships come to light. Bibliography During the preparation of the following catalogue the writers compiled a bibliography which it was hoped could be published here. It grew to such proportions, however, that the time required to get it ready and the cost of pubUcation became prohibitive. As a result, some of the references in the catalogue may be found to be inconveniently short; but in most cases an attempt was made to make the abbreviations fuller than in the majority of similar publications. Occasionally, a troublesome reference has been spelled out. Complete titles can usually be found by looking in the "Catalogue of the Books, etc., in the British Museum (Natural History)" by B. B. Woodward, which the present ^Titers have found very useful. Other useful but more specialized bibliographies can be found in the fossil papers listed below by Arnold (1903) and by Dall (1909) and in the Recent papers by Dall (1909) and by Oldroyd. Binney's "Bibliography of North American Conchology"i is useful for papers published before 1860, especially as in many cases it summarizes the papers, giving for each American species the name used, the page, figure, and date. Also, The Zoological Record, wliich began in 1864 and contains references to nearly all papers published since its inception, should not be overlooked by those who wish to make a thorough search into the literature. Sherborn's Index Animalium has recently made itself indispensable. Unfortunately only a small part of Sherborn's valuable work was available during the preparation of most of this catalogue. A few innovations in the details of arranging the references have been introduced in the interests of clarity. Misidentifications are not cited in the same way as ignorantly described new species, but the improperly used name is given as used in quotation marks. For example: "Pecten cerrosensis Gabb," Arnold, is given because it is less am- biguous than Pecten cerrosensis Arnold. The latter looks as if Arnold had described a homonym. In cases where the original usage of a name is not familiar to a reader, there is nothing to show in the latter form that the name is not available in that sense. Another very minor detail is in the capitahzation of the words Series, Volume, Part, part, Number, number. Article, article, etc. An attempt is made to use capital letters when the division indicated is separately paginated and to use small letters when the pagination is con- tinuous with the other divisions of the same rank. The writers regret .not always being consistent in this matter. The writers also regret that the specific references are in many cases not complete. Occurrences and occasionally even illustrations in some bulletins published by the U. S. Geological Survey and in a few other publications have sometimes been omitted. However, it is believed that the majority of the important references have been included. Recent papers by Pressler, Stewart, and others appeared too late to be incorporated. A few of the more important primarily paleontological papers dealing with the material of this catalogue are as follows (the works most important for the present subject are marked by an asterisk) : > Smithsonian Miscellaneous Collections, Pt. 1, March. 1863; Pt. 2. June. 1864. (Separate indices for American and foreign authors.) Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 99 Conrad, T. A.: U. S. Pacific R. R. Reports, Vol. 5, Appendix, pp. 322-329, pis. 2-9, 1856 (previously printed without plates in the U. S. House of Representatives, Document No. 129, July, 18.5.5); Vol. 6, pp. 69-73, pis. 2-5, 1857; Vol. 7, pp. 189-196, pis. 1-10, 1857; these publications reprinted (without the plates) by Dall in the appendix to the 1909 paper listed below. : "Descriptions of Three New Genera, Twenty-three New Species of Middle Tertiary Fossils from California and One from Texas," Proc. Acad. Nat. Sci. Phila., Vol. 8, pp. 312-316, 1857. *Gabb, W. M.: Geological Survey of California, Paleontology, Vol. 2, sect. 1, pt. 1, pp. 1-38, 1866; pts. 2, 3, pp. 39-124, with plates, 1868-9. Cooper, J. G. : "Catalogue of California Fossils," Seventh Annual Report of the California State Mineralogist, pp. 227-270, 1888. : "Additions to the Catalogue of California Fossils Obtained since 1888," California State Mining Bureau, Bull. No. 4, Pt. 3, pp. 23-33, 1894. (All of these early records are not included in the present catalogue.) Dall, W. H.: "Contributions to the Tertiary Fauna of Florida," Transactions of the Wagner Free Institute of Science, PhUadelphia, Vol. 3, pts. 1-6, 1890-1903. *Arnold, Ralph: "The Paleontology and Stratigraphy of the Marine Pliocene and Pleistocene of San Pedro, California," Memoirs of the California Academy of Sciences, Vol. 3, June 27, 1903; reprinted as Contributions to Biology from the Hopkins Seaside Laboratory of the Leland Stanford Junior University, No. 31. * : "The Tertiary and Quaternary Pectens of California," U. S. Geological Survey, Professional Paper 47, 1906. : "New and Characteristic Species of Fossil MoUusks from the Oil-bearing Tertiary Formations of Southern California," Proceedings of the IT. S. National Museum, Vol. 32, pp. 525-546, pis. 38-51, June 15, 1907; some of the plates reproduced in Bull. 309 of the U. S. Geological Survey. : "New and Characteristic Species of Fossil Mollusks from the Oil-bearing Tertiary Formations of Santa Barbara County, California," Smithsonian Miscellaneous Collections, Vol. 50, Publ. No. 1780, pp. 1-26 (Quarterly Issue, Vol. 4, pt. 4, pp. 419-447), pis. 50-58, December 13, 1907; plates 50 to 56 reproduced in BuU. 322 of the U. S. Geological Survey and plates 57 and 58 in Bull. 321. : "Descriptions of New Cretaceous and Tertiary Fossils from the Santa Cruz Mountains; California," Proceedings of the U. S. National Museum, Vol. 34, pp. 345-390, pis. 31-37, August 8, 1908. *Dall, W. H.: "The Miocene of Astoria and Coos Bay, Oregon," U. S. Geological Survey, Professional Paper 59, April 2, 1909. *Arnold, Ralph: "Paleontology of the Coalinga District, Fresno and Kings Counties, California," U. S. Geological Survey, Bull. No. 396, January 15, 1910, the plates reproduced in Bull. 398. Martin, Bruce: "Descriptions of New Species of Fossil Mollusca from the Later Marine Neocene of Cali- fornia," Univ. Calif. Publ. Geol., Vol. 8, no. 7, pp. 181-202, pis. 19-22, August 6, 1914. English, W. A.: "The Fernando Group near Newhall, California," Univ. Calif. Publ. Geol., Vol. 8, no. 8, pp. 203-218, pi. 23, November 7, 1914. Nomland, J. O.: "Fauna from the Lower Pliocene at Jacalitos Creek and Waltham Canyon, Fresno County, California," Univ. Calif. Publ. Geol., Vol. 9, no. 14, pp. 199-214, pis. 9-11, February 24, 1916. Moody, C. L.: "Fauna of the Fernando of Los Angeles," Univ. Calif. Publ. Geol., Vol. 10, no. 4, pp. 39-62, pis. 1, 2, October 11, 1916. Nomland, J. O.: "The Etchegoin Pliocene of Middle California," Univ. Calif. Publ. Geol., Vol. 10, no. 14, pp. 191-254, pis. 14-20, AprO 19, 1917. Howe, H. v.: "Faunal and Stratigraphic Relationships of the Empire Formation, Coos Bay, Oregon," Univ. Calif. Publ. Geol., Vol. 14, no. 3, pp. 85-114, pis. 7-12, September 8, 1922. Stewart, R. B.: "Gabb's California Fossil Type Gastropods," Proc. Acad. Nat. Sci. Phila., Vol. 78, pp. 287-447, pis. 20-32, 5 text figures, published January 3, 1927. Waterfall, L. N.: "A Contribution to the Paleontology of the Fernando Group, Ventura County, California," Univ. Calif. Publ. Geol., Vol. 18, no. 3, pp. 71-92, pis. 5, 6, April 6, 1929. Pressler, E. D.: "The Fernando Group in the Las Posas-South Mountain District, Ventural County, Cali- fornia," Univ. Calif. Publ. Geol., Vol. 18, no. 13, pp. 325-345, 4 text figures, September 30, 1929. Stewart, R. B.: "Gabb's California Cretaceous and Tertiary Type Lamellibranchs," Special Publication No. 3, Academy of Natural Sciences of Philadelphia, August 9, 1930. 100 San Diego Society of Natural History [Memoirs For the sake of students in California and others who are engaged in identifying specimens or are considering the naming of new species, it may be worth while to point out that many more species are known in the Recent fauna than have been reported from the best known Pliocene or Pleistocene fossil faunas. As many Recent species range back into the Pleistocene and Pliocene, it is probable that many more of them will be found in a fossil state and it is the duty of paleontologists to become familiar with the Recent literature, to try to correlate fossils with their living representatives, and before imposing a new name on the scientific world to be sure that the form which it is proposed to name has not already a name in the Recent fauna. The same is also true of Miocene species. Many species of the Miocene, Pliocene, and warm-water Pleistocene faunas of California are now living only south of the United States and do not appear in the checklist by Dall (1921), or in the work by Oldroyd (1924-27), which is an expansion and illustration of that checklist. Unfortunately the literature of the Mexican and Central American coast is very incomplete. Besides the general world iconographies of Martini and Chemnitz, Kiener, Reeve, Sowerby, and Tryon, there are only a few scattered works. Some of the most important works dealing with the living faunas of the Pacific coast of the Americas are as follows: Conrad, T. A.: "Descriptions of New Marine Shells from Upper California, collected by Thomas Nuttall, esq.," Journal of the Academy of Natural Sciences of Philadelphia, Series 1, Vol. 7, pp. 227-268, pis. 17-20, 1837; also various other papers in the Journals and Proceedings of the Academy of Natural Sciences and in the American Journal of Conchology. Hinds, R. B. : "The Zoology of the Voyage of H. M. S. Sulphur under the command of Capt. Sir E. Belcher . . . during 1836-42 . . . Mollusea," published 1844. Gould, A. A.: Various papers in the Proceedings of the Boston Society of Natural History and in the Boston Journal of Natural History; also "Mollusea and Shells of the U. S. Exploring Expedition," Report of the United States Exploring ExTJedition under the Command of Captain Charles Wilkes, Vol. 12, text, 1852; plates (folio), 1856; etc. Adams, C. B.: "Catalogue of Shells Collected at Panama, with Notes on Synonymy, Station, and Habitat," Annals of the Lyceum of Natural History of New York, Vol. 5, pp. 229-548, 1852; also issued as a separate. Carpenter, P. P.: "Catalogue of the Reigen Collection of Mazatlan Mollusea in the British Museum," July, 1855, to June, 1857. : "Report on the Present State of our Knowledge with Regard to the Mollusea of the West Coast of North America," British Association for the Advancement of Science, Report for 1856, pp. 159-368, 1857. : "Supplementary Report on the Present State of our Knowledge with Regard to the Mollusea of the West Coast of North America," British Association for the Advancement of Science, Report for 1863, pp. 517-686, August, 1864; reprinted with other papers and a general index in the Smith- sonian Miscellaneous Collections, No. 252, 1872. Dall, W. H.: "Descriptions of SLxty New Forms of Mollusks from the West Coast of North America and the North Pacific Ocean, with Notes on Others Already Described," American Journal of Conch- ology, Vol. 7, pp. 93-160, pis. 13-16, November, 1871. : "PreUminary Report on the Collection of Mollusea and Brachiopoda Obtained |by the U. S. S. Albatross] in 1887-88," Proceedings of the U. S. National Museum, Vol. 12, pp. 219-362, pis. 5-14, March 7, 1890. Stearns, R. E. C: "Report on the Mollusk Fauna of the Galapagos Islands, with Descriptions of New Species," Proceedings of the U. S. National Museum, Vol. 16, pp. 353-450, pis. 51, 52, 1893. : "The Shells of the Tres Marias and Other Localities Along the Shores of Lower California and the Gulf of California, ' Proceedings of the U. S. National Museum, Vol. 17, pp. 139-204, 1894. Dall, W. H.: "The Mollusea and Brachiopoda" (obtained by the Albatross in the Eastern Pacific during 1891, 1904, and 1905], Bulletins of the Museum of Comparative Zoology, Harvard College, Vol. 43, pp. 205-531, pis. 1-22, 1908. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 101 "Report on a Collection of Shells from Peru, with a Summary of the Littoral Marine Mol- lusca of the Peruvian Zoological Province," Proceedings of the U. S. National Museum, Vol. 37, pp. 147-294, pis. 20-28, November 24, 1909. Lamy, E.: "Pelecj-podes Recuillis par M. L. Diguet dans le Golfe de Californie (1894-1905)," Journal de Conchyliologie, Vol. 57, pp. 207-254, 1909. Zetek, James: "Los Moluscos de la Republique de Panama," La Revista Nueva, nos. 1 (July), 2 (August), 1918, reissued as a separate, 69 pp., 1918. Packard, E. L.: "Molluscan Fauna from San Francisco Bay," Univ. Calif. Publ. Zool., Vol. 14, no. 2, pp. 199-452, pis. 14-60, September 12, 1918. Dall, W. H.: "Summary of the Marine Shell-bearing MoUusks of the Northwest Coast of America, from San Diego, California, to the Polar Sea, ..." etc.. Bulletin 112 of the U. S. National Museum, February 24, 1921, (Additions and emendations appeared in the Proceedings of the U. S. National Museum, Vol. 63, Art. 30, 4 pp., April 12, 1923). Oldroyd, Mrs. I. S.: "Marine Shells of Puget Sound and Vicinity," University of Washington, Publications of the Puget Sound Biological Station, Vol. 4, March, 1924. : "The Marine Shells of the West Coast of North America," Stanford University Publications, University Series, Geological Sciences, Vol. 1 (Pelecypoda and Brachiopoda), 1924; Vol. 2, 3 pts. (Scaphopoda and Gastropoda, including the chitons), 1927. Tomlin, J. R. LeB.: "MoUusca of the St. George Expedition; (1) The Pacific Coast of North America," Journal of Conchology, Vol. 18, pp. 153-170, 1927; pp. 187-198, 1928. The writers regret that the 1930 paper by Stewart referred to in several places above did not appear in time for all of its nomenclatorial and other findings to be incorporated in the preparation of this catalogue. Some of the nomenclatorial discoveries were made possible by better library facilities than the present writers had access to. It is unfor- tunate that the unearthing of more obscure ancient publications will still threaten to upset the most carefully prepared nomenclatorial arrangements. A few changes have been made below in galley proof. The present writers wish to express to Dr. Stewart their appreciation of the kind of work his two papers on Gabb's types represent. It is to be hoped that someone will make a similar careful study of Conrad's and Carpenter's types. San Diego Society of Natural History Fossil Localities 40. Santa Barbara County. About 1}2 miles west of Goleta Point, and about 4 miles west-southwest of the town of Goleta, in fossiliferous soft sand overlying clay shale at beach on Campbell's Ranch. U. S. Grant, collector. Upper Pleistocene terrace. 41. Santa Clara County. Two or three miles southwest of Mayfield, in sandstone along a small creek. A speci- men of Ficiis secured here, probably at or near the tj-pe locality of Ficus stanfordensis Arnold. U. S. Grant, H. R. Gale, and L. W. Wiedey, collectors. Middle Miocene. 78. Ventura County. About half a mile south of Seacltff Station on Southern Pacific Railroad, about 8 miles north of Ventura, at the north end of a sea wall. A low terrace about 6 feet above sea level. ( = Stanford University loc. 536.) U. S. Grant, collector. Upper Pleistocene terrace. 97. Orange County. In the northern part of the San Joaquin Hills, at an elevation of between 125 and 150 feet, just south of a hill reaching 300 feet. On the map of the Santa Ana quadrangle (U. S. Geol. Surv., Ed. 1901) about 3'2 inch west of the "J" in "San Joaquin." Wayne Loel, collector. Upper Pleistocene terrace. 98. Los Angeles County. Fossiliferous deposit in a canyon in the mesa northwest of Santa Monica, about 350 yards west of the corner of Beverly Boulevard and Gary Street, just west of Toyopa Drive. F. C. Clark, coUector. Upper Pleistocene terrace. 99. Los Angeles County. Just west of Newport, at top of 25-foot embankment at edge of mesa. The fossiliferous stratum continues for some distance along the edge of the mesa. A. M. Strong and U. S. Grant, col- lectors. Upper Pleistocene terrace. 101. Santa Barbara County. About 100 yards west of the pier at the old Bath-house; in a sandstone embank- ment at the beach. Called "Bath-house Beach" by Arnold, 1903. U. S. Grant, collector. Upper Pliocene. 102 San Diego Society of Natural History [Memoirs 151. Santa Barbara County. On Maria Ygnacia Creek, about l}i miles northeast of Goleta, in nearly vertical strata of unconsolidated fine sand. Van Court Warren, collector. Upper Pliocene. 201. Los Angeles County. About 20 feet down the south side of ridge from little knoll which is N. 75° W. of the first important fork of Elsmere Canyon below the granite contact; about the middle of the south boun- dary of the S.E. }{, N.E. H, Sec. 7, T. 3 N., R. 15 W., Mt. San Bernardino B. and M.; elevation about 2025 feet; in conglomerate, upper horizon, Elsmere Canyon just below coarse Saugus conglomerate capping; about 300 feet stratigraphically above the lower horizon; most easily found by following along the ridge. H. R. Gale, collector. Middle or lower Pliocene. 202. Los Angeles County. A path cut into the side of the main canyon leads up a side canyon about opposite locality 201. It follows up the side canyon past a prospect in the oil sand and soon reaches the granite contact. Then it follows around a contour onto the next ridge to the southwest and turns up the crest of the ridge, ending just over the first hump. To the southwest on the hiU slope and along the next creek is locality 202, near the center of the northern boundary of the N.W. }4, S.W. J4 of Section 8. In oil-stained sandstone just above the granite. An attempt was made to divide the 25 -|- feet of fos- sOiferous strata into three faunules, upper, middle, and lower, respectively. ( = Stanford University loc. 177.) See also localities 207 and 208. H. R. Gale, collector. Lower Pliocene. 203. Los Angeles County. On the hill slope along the N.W. bank of the main branch of Elsmere Canyon just above the little side creek which heads off to the northwest and just below the big waterfall. S.E. Mi N.W. }4 of Section 8. In about 80 feet above the granite there are ten fairly distinct fossiliferous strata, ■ which it was attempted to separate. Locality 203a is under the brush just above the waterfall. H. R. Gale, collector. Lower Pliocene. 204. Los Angeles County. In the bed and along the banks of the small side creek mentioned under 203. Locality 204a is on the steep canyon wall just west of the side creek. Elsmere Canyon. H. R. Gale, collector. Lower Pliocene. 205. Los Angeles County. On the same northwest side of the canyon west of locality 204a where the slope is less steep below with a vertical cliff above. Most of the fossils have weathered out of the cliff. H. R. Gale, collector. Lou-er Pliocene. 206. Los Angeles County. Along the north fork of the canyon (the north fork is not so apparent from the creek bed below because of its hanging mouth), and eastward toward locality 205 in the main canyon. S.W. }4, N.W. a of Section 8. Only the higher strata of locality 203 are present. See also locality 209. ( = ? University of California loc. 1601.) Elsmere Canyon. H. R. Gale, collector. Lower Pliocene. 207. Los Angeles County. On the hill slope to the north of the end of the path on the ridge near locality 202, near Elsmere Canyon. H. R. Gale, collector. Lower Pliocene. 208. Los Angeles County. Near the oil prospect mentioned under locality 202 and up little gulch to the north. Locality 208a is in the cut made for the path in the wall of the main canyon just as it turns into the hanging side valley. Locality 208 proper is in the N.W. M, S.W. H of Section 8, as shown on the map. Elsmere Canyon. H. R. Gale, collector. Lower Pliocene. 209. Los Angeles County. West of locality 205 and southwest of locality 206 below the forks of the canyon on the north side of the main canyon. S.W. }4, N.W. M of Section 8. In sandy shale and concretions. Elsmere Canyon. H. R. Gale, collector. Lower Pliocene. 210. Los Angeles County. Detritus in the bed of Elsmere Creek. H. R. Gale, collector. Lower Pliocene. 211. Los Angeles County. On the southwest limb of the synclkie in the ridge over the southern end of the Fer- nando Pass railroad tunnel, half way up the slope opposite the point where the recently constructed real estate development side road turns back along the northeast side of the canyon, and below the first high point on the ridge northwest of the place that the tunnel passes mider (loc. 214). About the center of the eastern boundary of the S.E. U, S.W. }i, Sect. 13, T. 3 N., R. 16 W., Mt. San Bernardino B. and M. Pico formation but a higher horizon than found in Elsmere Canyon. H. R. Gale, collector; spring, 1927. Middle Pliocene. 212. Los Angeles County. On the dip-slope of the north limb of the syncline at the head of a broad amphitheatre north of locality 211, on the map not far below the first "N" in "TUNNEL." N.W. }i, S.W. }4 of Section 13. H. R. Gale, collector; spring, 1927. Middle Pliocene. 213. Los Angeles County. On the top of the same ridge about a mile northwest of locality 212, near the figures 2000 of the 2000-foot contour on the map. About the center of the N.W. H of Section 14. This locahty is the northwest end of the outcrops of the fossiliferous stratum represented by localities 211 to 214. It was pointed out by Mr. J. E. Eaton. H. R. Gale, collector; spring, 1927. Middle Pliocene. 214. Los Angeles County. On summit of ridge directly over railroad tunnel. S.W. M> S.E. }i of Section 13. This locality is the southeast limit of the outcrops of the fossiliferous stratum, where the outcrops on the two limbs of the syncline curve around the end of the ridge and join. H. R. Gale, collector; spring, 1927. Middle Pliocene. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 103 215. Los Angeles County. On the top of the main ridge east of Fernando Pass, just below the granite contact. North boundary of the S.W. H, S.W. M of Section 17, T. 3 N., R, 15 W., Mt. San Bernardino B. and M. Hard calcareous sandstone forming a knoll on the ridge. Elevation 2650 feet. ( = ? University of California loc. 3588.) H. R. Gale, collector; spring, 1927. Lower Pliocene. 216. Los .\ngeles County. Coarse sandstone stratum about 12 feet above the granite at head of canyon just over the first hump to the north of locality 215. A path runs from near locality 215 northward along a side ridge toward Elsmere Canyon. After passing around the head of the second minor canyon which leads off to the west the path swings down on the west flank of the ridge. Locality 216 is on the north side of this second side canyon not far below the path and the top of the ridge. N.W. %, S.W. li of Section 17. Locality 216a is Vi. mile down the path from 216, toward Elsmere Canyon. H. R. Gale, collector; spring, 1927. Lower Pliocene. 217. Los Angeles County. Top of hill 2223 on the divide between Holser and San Martinez Grande canyons (so described by Kew in Bull. "753 U. S. Geol. Survey, p. 79, 1924; but the divide meant is the one going over into the canyon marked San Martinez Chiquito on the map). S.E. ]4,, N.E. }^, Section 7, T. 4 N., R. 17 W., Mt. San Bernardino B. and M. (= U. S. National Museum loc. 8140 and Stanford University loc. 178.) H. R. Gale, collector; summer, 1927. Middle Pliocene. Locality 217a is on ridge running to the east-southeast. Locality 217b is on the the ridge to the south-southeast. It may be University of California loc. 1637, which could not be located in the place described. Locality 217c, detritus from Holser Creek; could have come from no other horizon. 218. Ventura County. Sulphur Canyon, east of South Mountain, on the east side of the long, narrow ridge run- ning northward from the divide just east of the road, almost N. 45° \V. from B. M. 1237. Locality discovered by Glenn E. Bader. H. R. Gale, collector; summer, 1927. Upper Pliocene. 219. Ventura County. Sexton Canyon, Santa Paula Quadrangle, just north of the junction with Lake Canyon, in clay bluff on right side of canyon going up. U. S. Grant, H. R. Gale, and Phil Wright, collectors; summer, 1927. Upper Pliocene shaly fades. 220. Ventura County. Knoll to the northwest of little, short, flat-bottomed valley west of Timber Canyon, Santa Paula Quadrangle. Fossils weather out on the southern hUl slope below fanglomerate capping. See also locality 225 to the west. (= Stanford University loc. 254.) H. R. Gale, collector; summer, 1927. Upper Pliocene. 221. Ventura County. Second conglomerate ridge on the east side of Canada de Aliso, north of Canada Larga about }4 mile, Ventura Quadrangle. ( = Stanford University loc. 165 and University of California loc. 7096 — Waterfall.) H. R. Gale, collector; summer, 1927. Middle (or upper ?) Pliocene. 222. Ventura County. At the head of Canada de las Encinas about half way up the south side of the ridge sep- arating it from Manuel Canyon, Ventura Quadrangle. ( = Stanford University loc. 527.) H. R. Gale, collector; summer, 1927. Middle (or upper ?) Pliocene. 223. Ventura County. In conglomerate ledge on east side of the west branch of O'Hare Canyon just above the forks, about 13.2 miles from the mouth of the canyon, Santa Paula Quadrangle. (= Stanford Uni- versity loc. 234.) H. R. Gale, collector; summer, 1927. Middle (or upper ?) Pliocene. 224. Ventura County. In sandstone on ridge }i mile to the northwest of locality 223. H. R. Gale, collector; summer, 1927. Middle (or upper f) Pliocene. 225. Ventura County. On the west side of the west branch of the large unnamed canyon between Timber Canyon and Santa Paula Creek, near the figures 1250 of the 1250-foot contour on the map. On the middle of the north border of the N.E. U, N.E. M, Section 35, T. 4 N., R. 21 W., Mt. San Bernardino B. and M., Santa Paula Quadrangle. In conglomerate about half way up slope. Locality 225a is on top of the ridge in sandy shale to the southwest. H. R. Gale, collector; summer, 1927. Upper Pliocene. 226. Ventura County. East side of Smith Canyon (first canyon east of Torrey Canyon) near its mouth in cal- careous sandstone rib not far above the canyon bottom. Immediately overlying stratigraphically the Modelo sandstones, which contain poor fossils on the top of the ridge. ( = ? U. S. National Museum loc. 8143.) H. R. Gale, collector; sununer, 1927. Middle Pliocene (?). 227. Los Angeles County. On the northwest side of ridge running northeast from hUl 2006, S. 33° W. of Humph- reys Station, just north of the center of the S.W. >i of Section 27, T. 4 N., R. 15 W., Mt. San Bernardino B. and M. (= University of California loc. 3587.) H. R. Gale, collector; summer, 1927. Lower Pliocene. 228. Los Angeles County. Two-fifths of a mile south of north line of T. 3 N. and 1/10 mile east of meridian 118° 35', mostly on south side of ridge immediately above bend in creek, southeast of Pico Canyon. (= U. S. National Museum loc. 8146.) H. R. Gale, collector; summer, 1927. Middle Pliocene. 104 San Diego Society of Natural History [ Memoirs 229. Los Angeles County. On the summit of ridge near old water tank, west of the sharp bend in Pico Canyon which is just below the town of Pico. (= University of California loc. 1603.) H. R. Gale, collector; summer, 1927. Lower or middle Pliocene. 230. Los Angeles County. Just below top of steep southern escarpment of ridge north of potrero, or flat-bottomed valley, which heads west of the bend in Pico Canyon, 1 i^s miles N. 30° W. from the town of Pico. More easily accessible from the northeast or northwest, auto roads running in from the Santa Clara Valley (= ? U. S. National Museum loc. 1850. U. S. National Museum loc. 1842 could not be located from the description.) H. R. Gale, collector; summer, 1927. Middle Pliocene. 231. Los Angeles County. At the base of the escarpment below locality 330. H. R. Gale, collector; summer, 1927. Middle Pliocene. 232. Los Angeles County. On ridge extending to the northward in northeast corner of Section 32, T. 4 N., R. 15 W., Mt. San Bernardino B. and M., between Soledad and Placerita canyons, but more easily accessible from the former; a few poor fossils in a hard calcareous sandstone. H. R. Gale, collector; summer, 1927. Lower Pliocene. 233. Ventura County. Immediately below and east of top of ridge which makes the northwest corner of El Conejo Land Grant; north of Arroyo Santa Rosa. FossUiferous unconsolidated sandstone overlying Sespe ? formation. ( = U. S. National Museum loc. 8141.) U. S. Grant, collector; July, 1927, and January 4, 1928. Las Posas formation, lower Pleistocene. 234. Ventura County. Fossil reefs in old road-cut, about 75 feet above creek bottom on east side of Barlow Canyon (Santa Paula Quadrangle Map. U. S. G. S.) about yi mile from mouth of canyon. Strike about N. 85° E.; dip about 37° south. (May be the same as Arnold's "Barlow Ranch Pleistocene.") U. S. Grant, collector; July 18, 1927. Las Posas formation, lower Pleistocene. 235. Ventura County. On divide between Hampton and Ali.so canyons, due west of junction of Hampton and Wheeler canyons, on north side of hilltop at about S50-foot elevation, Santa Paula Quadrangle. U. S. Grant, collector; July 11, 1927. Las Posas formation, lower Pleistocene. 236. Ventura County. Just north of top of hill (at elevation of about 1100 feet) on east side of Harmon Canyon, V/i miles above its confluence with the Santa Clara Valley. Just above upper Pliocene clay shale. U. S. Grant, collector; July 13, 1927. Las Posas formation, lower Pleistocene. 237. Ventura County. Fossils weathered out on small north-south ridge at about 750-foot elevation a half mile west of locality 244 in Sexton Canyon, at head of and 9/10 mile above mouth of small canyon lying half way between Sexton and Barlow canyons. H. R. Gale, collector; summer, 1927. Las Posas formation, loicer Pleistocerie . 238. Ventura County. East side of Adams Canyon about 1 mile above mouth, just at south edge of mouth of side canyon from east, in yellowish sandstone at or near base of Las Posas formation near contact with typical Pico clay shale. A conglomerate stratum occurs stratigraphically above (south of) this fossil moUuscan reef. About 3 miles west of Santa Paula. U. S. Grant, collector; July 1, 1927. Las Posas fornwtion, lower Pleistocene. 239. Ventura County. Divide between Adams and O'Hare canyons, south side (slope) of 800-foot hill about 1 mile north of Santa Clara Valley. Sandstone near Pico contact. (This is near Stanford University loc. 213.) U. S. Grant, collector. Las Posas formation, lower Pleistocene. 240. ^'entura County. Fossiliferous sandstone exposed on cliff on west side of sharp ridge between Adams and Fagan canyons, about 100 yards south of 950-foot hill, ^i mUe north of Santa Clara Valley, Santa Paula Quadrangle. U. S. Grant, collector. Las Posas formation, lower Pleistocene. 241. Ventura County. On ridge ascending from the southwest up 1200-foot hiU, on the east side of Harmon Canyon, IJ/2 miles above mouth. (Harmon Canyon is 2H niiles north-northeast of Montalvo.) Pico formation just below Las Posas contact. Pecten fragments. U. S. Grant, collector; July, 1927. Upper Pliocene. Locality 241a is 200 yards south of locality 241. Float from the Las Posas formation, loicer Pleistocene. 242. Ventura County. West side of Adams Canyon, about 1 mile above mouth, in fossiliferous sandstone at foot of prominent hill. (This is just across Adams Canyon from loc. 238.) Santa Paula Quadrangle. U. S. Grant, collector; July 5, 1927. Las Posas formation, lower Pleistocene. 243. Ventura County. Base of Las Posas formation on west side of Adam's Canyon, Santa Paula Quadrangle, on spur northeast of 1000-foot hill, just beyond houses. (Same as loc. 242.) H. R. Gale, collector; summer, 1927. Las Posas formation, lower Pleistocene. 244. Ventura County. At back of sheep corral, on west side of Sexton Canyon, Santa Paula Quadrangle, about a mile above the mouth and about / 8 mile south of the jimction of Lake and Sex-ton canyons, at or near the base of the Las Posas formation in brownish, fine-grained sandstone, which strikes about N. 70° E., and dips 30° south. H. R. Gale and U. S. Grant, collectors. Las Posas formation, lower Pleistocene. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 105 245. Ventura County. Fossils on slope on the north side of short side canyon leading west-northwest from the main canyon which enters Santa Clara Valley about 1 mile east of the mouth of Harmon Canyon, Santa Paula Quadrangle. Apparently Pico arenaceous clay shale not far stratigrajihically below the Las Posas contact. Fragments of Palinopeclen, etc. U. S. Grant, collector; July 13, 1927. Upiper Pliocene. 246. Ventura County. Fossil reef on the southwest cliff of a ridge and weathered out fossiliferous sandstone blocks on slope of a spur leading west toward ranch houses near central part of Section 29, T. 4 N., R. 20 W., San Bernardino B. and M.; about '2 mile from mouth of canyon, in hills on east side of the canyon; east of Timber Canyon. U. S. Grant, collector; January 2, 1928. Las Posas formalion, lower Pleistocene. 247. Ventura County. About 1850 feet north of the corner of Poli and Kalorama streets, ^'entura, in canyon draining south and about 1250 feet north of bridge across mouth of canyon, in fossiliferous sandstone, dipping south. U. S. Grant, collector; January 3, 1928. Middle of Las Posas formation, lower Pleistocene. 248. Ventura County. Outcrop of indurated basal Las Posas sandstone fossil reef 30 to 50 feet south of summit of hill just over 1200-foot altitude, a little south of center of Section 35, T. 4 N., R. 21 W., San Ber- nardino B. and M. The fossils are in cemented sandstone blocks just on the south slope of this hill, near the summit. Stratigraphically overlying this fossU zone are some brown conglomerate members. Strike N. 60° E., dip 70° to 80° south. U. S. Grant, collector; January 4, 1928. Las Posas formation, lower Pleistocene. 249. Ventura County. About 1600 feet north of the intersection of Kalorama and Poli streets, Ventura, in fos- siliferous sandstone exposed in canyon draining south. This locality is about 250 feet south of locality 247. V. S. Grant, collector; January 3, 1928. Middle of the Las Posas formation, lower Pleistocene. 250. Ventura County. About 1250 feet north of the corner of Kalorama and Poli streets, Ventura, in fossiliferous sandstone in canyon draining south. This locality is about 350 feet south of locality 249. U. S. Grant, collector; January 3, 1928. Middle of the Las Posas formation, lower Pleistocene. 251. Los Angeles County. In the little saddle baoli of the most prominent little tongue sticking out from the west side of San Martinez Grande Canyon, near its mouth. Sandstone bed in shale, (cf. loc. 262.) H. R. Gale, collector (41); summer, 1928. Middle Pliocene. 253. Los Angeles County. Palomas Canyon, on the south side of ridge south of Palomas Canyon between the second and third minor canyons above the junction with Violin Canyon. H. R. Gale, collector (33); summer, 1928. Lower middle Pliocene. 254. Ventura County. Sulphur Canyon, south side of Sulphur Mountain, on top of east-west ridge southeast of big turn in the canyon at the base of the Pliocene section or the top of the Miocene. Fossils preserved only in one or two large concretions. H. R. Gale, collector (34) ; summer, 1928. Lower Pliocene. 255. Los Angeles County. Hasley Canyon; in shale in and near road cut almost at the head of the canyon, directly east of hill 2100 and south of the section number of Section 32 on the map. H. R. Gale, collector (35); summer, 1928. Middle Pliocene, shaly fades. 256. Los Angeles County. On the northwest corner of hill 1668 east of the big bend in San Martinez Chiquito Canyon. H. R. Gale, collector (38) ; summer, 1928. Middle Pliocene, oyster bed fades. 257. Los Angeles County. On minor spur projecting southward on side of synclinal ridge west of Fernando Pass, in the west H of the S.W. }4 of Section 13, R. 16 W., T. 3 N., San Bernardino B. and M. H. R. Gale, collector (37) ; summer, 1928. Middle Pliocene, nornuil fades. 258. Los Angeles County. Oyster reef bed running along the crest of the ridge east of San Martinez Chiquito Canyon about half way between the mouth of the canyon and the big bend. H. R. Gale, collector (36); summer, 1928. Middle Pliocene, oyster bed fades. 259. Los Angeles County. Continuation of the horizon represented at locality 229, the lower zone of Pico Canyon, probably lower Pliocene, on the north side of hill 2010 about a mile and a half west of Pico. In a hard calcareous sandstone (compare localities 232, 254). H. R. Gale, collector (46); summer, 1928. Lower or middle Pliocene. 260. Los Angeles County. On the top of hill 2018 west of the northwest branch of San Martinez Chiquito Canyon. H. R. Gale, collector (40); summer, 1928. Middle Pliocene, normal sandy fades. 262. Los Angeles County. On the east side of San Martinez Grande Canyon northeast from locality 251. Probably approximately the same horizon. H. R. Gale, collector (42); summer, 1928. Middle Pliocene. 263. Los Angeles County. On the south side of the ridge north of the junction of Towsley and Wiley canyons. H. R. Gale, collector (43) ; summer, 1928. Middle Pliocene, normal sandy fades. 264. Los Angeles County. A continuation of 263 across the main canyon to the east. H. R. Gale, collector (44); summer, 1928. Middle Pliocene, normal sandy fades. 106 San Diego Society of Natural History [ Memoirs 265. Los Angeles County. Continuation of same bed in the bottom of the side canyon north of Gavin Canyon, in the S.E. 1-nopsis meth. Moll. gen. spec, editio altera, p. 119, 1830 (revised spelling); Chil- dren, Quarterly Jour. Sci. Lit. Arts, p. 300, January, 1823; Bucquoy, Dautzenberg and Dollfus, Moll. Mar. Roussillon, Vol. 2, fasc. 26, p. 718, 1898. Stephanopus Seacchi, Osserv. Zool., p. 3, 1833. Type (by subsequent designation. Children, 1823), "Solenomya mediterranea" Lamarck, = Solemya mediterranea Lamarck, = Solemya togata (Poli), 1791, Test. Utr. Sic, Vol. 2, p. 42, pi. 15, fig. 20, as "Tellina," fide Bucquoy, Dautzenberg and Dollfus; Recent, Adriatic and Mediterranean Seas, Atlantic Ocean off Spain, Madeira, West Africa, etc. Shell elongate, Solen-shaped, rounded and gaping at both ends, covered by a rather tough, horny epidermis which extends beyond the ventral margins of the valves. Sculpture obscure or consisting of low radial bands which may project beyond the ventral margin of the shell or become separated by indentations of the margm. Umbones posterior, not promment; hinge edentulous, with an obliquely inclined, somewhat triangular chondrophore, below which is a reinforcing rib on the inner surface of the valve, similar to the internal rib of Siliqua. Pallial Ime obscure, without definite sinus. Size from very small {S. occidentalis Desh., S. vellum Say, Florida and Massachusetts respectively, 7 to 15 mm. length) to large {S.johnsoni Dall, length, 115 mm.). Geologic range: Paleozoic to Recent, (Carboniferous, possibly from Silurian, to Recent) . Distribution: Widely distributed; uncommon, generally deep water. Dall (1908) has proposed the two subgenera, Petrasma (type, »S. borealis Totten) and Acharax (type, S. johnsoni Dall), but the hinge characters upon which they are based are not apt to be visible on fossil specimens. Dall places S. ventricosa Conrad in Acharax, probably because of the external similarity between Conrad's species and Univ. Calif. Publ. Geol., Vol. 14, p. 97, 1922. VoLUMK I j Pliocene and Pleistocene Mollusca of California 135 and they are of the opinion that Dall drew specific Unes far too fine in this genus. In a collection of specimens labeled Glycymeris subobsoleta (Carpenter) from the Pleistocene of San Pedro there are occasional individuals with a prominent umbo as in Arnold's figure of barbarensis. We have, therefore, tentatively considered the "barbarensis" of Arnold (1909) synonymous with subobsoleta Carpenter; but it is not yet certain whether the shells which Conrad named barbarensis are the same as Carpenter's variety. A study of Con- rad's type, which according to Dall is in the National Museum, may settle this point. As many species of Glycymeris are diflficult to differentiate, it is probable that not enough allowance has been made for individual variation, for differences in shell charac- ters produced by the direct influence of habitat, and for reduction or obliteration of sculp- ture by erosion. Glycymeris kashewarowi (Grewingk) Pechmcultis kasheu-aroiii Grewingk, Riissisch-Kaiserliche Mineralogische Gesellschaft zu St. Petersburg. Verhand- lungen for the years 1848 and 1849, p. 352, pi. 5, figs. 3a-d, 1S50; Dall, U. S. Geol. Surv., Prof. Paper .59, p. 109, 1909. Peclunculus kashevaroffi Grewingk, Dall, Seventeenth Ann. Rept., U. S. Geol. Survey, Pt. 1, p. 844, 1896. Glycimeris kasherarofi Grewingk, Dall, Wash. Acad. Sci., Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 112, 1904 (reissued by Smithsonian Inst., 1910). Miocene: St. Paul Island, Unga Island and Kadiak Island, off Alaska (Grewingk; Dall, 1896); Peninsula of Alaska, and near Tonki Cape, Igatskoi Bay, Island of Kadiak (Dall, 1934). This species looks much like Glycymeris gabbi Dall, but may have stronger ribs, wider than the interspaces. It has about nineteen distinct growth rings and a hinge with a straight row of fourteen small teeth across the middle, changing abruptly to the curving row of large side teeth, seven to a side. There are several chevron-shaped grooves under the beaks.' Glycymeris grewingki Dall Glycymeris greuiiigki Dall, U. S. Geol. Surv., Prof. Paper 59, p. 107, pi. 2, fig. 13, Ajjril 2, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, no. 212, p. .590, 1913 (including G. gahhi and G. conradi Dall as synonyms); Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 97, 1922; Waterfall, Vol. 18, pp. 78, 82, 1929. Glycymeris conradi Dall, U. S. Geol. Surv., Prof. Paper 59, p. 107, pi. 11, fig. 2, April 2, 1909, not Axirisea conradi Whitfield, U. S. Geol. Surv., Monograph 9, p. 230, pi. 29, figs. 10-11, 1885. Glycymeris gahhi Dall, U. S. Geol. Surv., Prof. Paper 59, p. 108, pi. 11, fig. 5, April 2, 1909. Glycymeris coalingensis Arnold, U. S. Geol. Surv., Bull. .396, p. 80, pi. 19, fig. 3, January 15, 1910; Bull. 398, pi. 41, fig. 3, 1910; Arnold and Hannibal, Proc. .\mer. Philos. Soc, Vol. 52, p. 592, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 418, 1915; Martin, Vol. 9, p. 252, 1916; Nomland, Vol. 10, pp. 220, .300, 1917. Glycymeris larrala Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 167, 1924, new name for G. conrndi Dall, not Whitfield. Type specimens: Of grewingki, conradi, gabbi, and coalingensis, in U. S. National Museum. Type localities: Of grewingki, conradi and gabbi, Miocene of Astoria, Oregon; of coalingensis, Glycymeris bed on north side of Alcalde Canyon, two miles northeast of Alcalde, Coalinga district, California, Etchegoin formation. Pliocene. Miocene: Empire formation of Astoria, Oregon (Dall, 1909; Arnold and Hannibal, 1913; Howe, 1922); San Pablo formation of middle California (Clark, 1915); Santa Margarita formation, upper Miocene, north of Coalinga (Nomland, 1917). I Eichwald, p. 125. 1871. thinks that this species niight be a synonym of "Cardium" aleuticnm. He attributes them both to the Cretaceous, probably erroneously. See note, p. 275. 136 San Diego Society of Natural History [Memoirs Pliocene: At various localities in the Etchegoin formation of the Coalinga district (Arnold, 1910; Arnold and Anderson, 1910; Nomland, 1917) ; Merced formation south of San Francisco (Arnold and Hannibal); Etchegoin of Sargent oil field (Martin, 1916); "lower Pico" near Ventura [middle Pliocene] (Water- fall). This species has been well figured and described under its vai-ious names. Weather- ing can entirely change the appearance of the sculpture, which may account for some of the synonyms noted above. Glycymeris maculata (Broderip) Pcctiiricidus maculaius Broderip, Proc. Zool. Soc. London for 1832, p. 126, 1832; Reeve, Conch. Icon., Vol. 1, Pectun- ndus, sp. 4, pi. 1, fig. 4, 1843; Hanley, Cat. Rec. Biv. Shells, p. 164, pi. 19, fig. 34; Mabille, Bull. Soc. Philom., Paris, Ser. 8, Vol. 7, p. 71, 1895; Lamy, Jour. Conchyl., Vol. 57, p. 209, 1909. Pectuncidus giganieus Reeve, Conch. Icon., Vol. 1, Pectunculus, sp. 3, pi. 1, figs. 3a-6, February, 1843. Pectunculus (Axinsea) maculatus Broderip, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 147, 1894. Glycymeris gigantea Reeve, Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 466, 1926; Hanna and Hertlein, Vol. 16, p. 140, 1927. Pliocene: Coyote Mountain, western lm])crial County (Hanna, 1926); Coronados and Carmen Islands, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Santa Rosalia, Gulf side of Lower California, Mexico (collected by Marcel Touwaide); upper Quaternary of San Ignacio Lagoon, west side of Lower California, Mexico (Jordan). Recent: Gulf of California, Mexico, to Peru (Jordan). This species attains a large size and has a strong, thick, very convex shell. The umbo protrudes prominently above the dorsal margin of the shell. The radial ribbing is reduced to very low relief or is obsolete, but the surface is finely and evenlj' radially striated. The hinge plate is heavy, with a curved series of stout chevron-shaped teeth which may be interrupted in the middle by the basal line of the ligamental area. The slight difference in color pattern between G. gigantea Reeve and G. maculata Broderip is not believed to be significant by the present authors, hence, the older name has been used. The variations in shape noticed in a series of specimens is partly due to the influence of a rocky habitat. There is a very similar Japanese species. Glyc3rmeris inaequalis (Sowerby) Pectunculus insequalis Sowerby, Proc. Zool. Soc. London for 1832, p. 196, March, 1833; not of Sowerby, Zool. Beechey's Voy., pi. 32, fig. 3, 1839, fide Dall, 1909; Reeve, Conch. Icon., Vol. 1, Pectunculus, sp. 16, pi. 4,.fig. 16, 1843. Glycymeris insequalis Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 37, pp. 155, 254, 1909. Shell subcordate, solid, heavy, with obtuse radial ridges; lilac gray or white with four or five broad rusty or blackish transverse bands, irregularly disposed; interspaces of the ribs striated; liga- ment short and a very small part of it liehind the umbones. (Dall, 1909.) Pleistocene: Coast of Oaxaca, Mexico (collected by R. H. Palmer), (Dall, 1909). Recent: Mazatlan, Mexico, south to Sechura Bay, Peru (Dall). Glycymeris corteziana DaU Glycymeris corteziana Dall, Proc. U. S. Nat. Mus., Vol. 52, p. 402, December 27, 1916; Bull. 112, U. S. Nat. Mus., p. 15, 1921; I. S. Oldroyd, Stanford Tniv. Publ. Geol., Vol. 1, p. 42, pi. 3, fig. 7, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In U. S. National Museum, Cat. No. 212,431. Type locality: On edge of Cortez Bank, in 67 fathoms, off California. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Forrester Island, Alaska, to Cortez Bank, California (Dall, 1921). Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 137 This is a small species, with a finely concentrically sculptured surface and less con- spicuous fine radiating strise. The beaks are small and the ligamental area very narrow. The type measures 22 mm. in length and 20 mm. in height. The " Pectunculus" patulus Conrad, 1849, was considered by Dall to be a poor internal cast of Lucina acutilineata, under which we have placed it as a synonym. "Pectunculus" nitens Conrad^ was considered by Clark= to be a LwiopsisK It occurs in the Miocene shales at Astoria, Oregon. A number of forms have been named from the earlier Tertiary. Genus ARCA Linnaeus, 1758 Area Limiffius, Syst. Nat., Ed. 10, p. 693, 1758; Schumacher, Ess. Nouv. Syst. Hab. Vers Test., pp. 171, 172, 1817, type cited Area antiquata Linnseus; Children, Quart. Jour. Sci. Lit. and Arts, p. 319, pi. 6, fig. 65, January, 1823, type cited A. toriuosa Linnaeus. Anadara Gray, Proc. Zool. Soc. London for 1S47, p. 198, Nov., 1847, type (by original designation), Area antiquata Linnaeus. Scapharca Gray, Proc. Zool. Soc. London for 1847, p. 198, Nov. 1847, type (by original designation), Area inxquivalvis Bruguiere, Ency. Meth., Vers, Pt. 1, p. 106, 1789; DaU, Trans. Wagner In.st. Sci., Vol. 3, p. 617, 1895. Anomalocardia (Ivlein) H. and A. Adams, Genera of Recent MoUusca, Vol. 2, pp. 535, 536, 1858, example A. antiquata Linnaeus, pi. 124, figs. 5, 5a. Diluvarca Woodring, Carnegie Inst. Publ. No. 366, pp. 40, 41, 1925, type (by original designation) Area diluvii Lamarck. Type (by subsequent designation, Schumacher, 1817), Area antiquata Linnseus, Syst. Nat., Ed. 10, p. 694, 1758. Shell suhciuadrate or trapezoidal, vontricosp, ribbed, striated or cancellated; hinge straight, with two series; of similar comb-like (taxodont) teeth. The various natural (and unnatural) groups of Areas have been well supplied with names, and some confusion has resulted from the lack of agreement concerning the types of the subdivisions. The synonymy and discussion in the present paper has been reduced to the minimum required to make clear what the present authors consider the natural systematic arrangement of the CaUfornia Pliocene and Pleistocene species. Subgenus ARCA, s. s. Shell of medium size, inequilateral, heavy, ventricose, without byssal gape; umbones high, stout; sculpture consisting of radial flattened ribs and channeled interspaces, the ribs sometimes multiple or modified by granules or beads ; cardinal area generally with chevron-shaped grooves and sometimes horizontal striae parallel to hinge margin; teeth in two series not separated in the middle. The typical subgenus was formerly thought to be based upon Area noce Linnaeus, according to the type designation of Gray, 1847. However, nearly a quarter of a century earlier, Children (1823) had designated Area toriuosa Linnseus as genotype, and still earlier Schumacher* had definitely designated Area antiquata Linnseus. Schumacher's action makes it possible to retain the name Area in a sti'ict sense for a majority of the Pacific coast species formerly assigned to Area in a broad sense. Anadara Gray, 1847, is an exact synonym of Area, s. s., having the same genotype. Diluvarca Woodring was based upon a misconception. In 1925 Woodring pubhshed fig- ures (pi. 4, figs. 1 and 2) furnished him by the General Secretary of the Linnsean Society 1 Geol. U. S. Explor. Exped. (Wilkes), Vol. 10, p. 726, Atlas, pi. 18, figs. 9a-b, 1849. » Univ. Calif. Publ. Geol., Vol. 15, p. 81, 1924. ■A. Sassi, Giorn. Ligustico, Vol. 1, Pt. 6, p. 476, 1827. ' Ess. Nouv. Syst., p. 172. Schumacher's exact words are: "Pour le type du genre j'ai donn6 la 6g. 2, PI. six. de la charniSre de VArca antiquata Lin. qu'on trouve figur^e dans Chemn. 7. pag. 201. Tab. 55. fig. 548." 138 San Diego Society of Natural History | Memoirs of London of Linnseus' type specimen of Area antiquata, and stated that along with Hanley's figure of the exterior (Ipsa Linnsei Conchylia, pp. 93-95, pi. 4, fig. 3, 1855) these photographs "show that Area antiquata externally resembles some of the American species of Argina, but has a byssal gape. Its cardinal area is moderately wide, but no ligament grooves are visible. The hinge is heavy; the anterior series of teeth is relatively long and not clearly separated from the posterior series. There are no similar Tertiary or living American Areas." Examination of Woodring's figure of the interior shows that the hinge is not like that of Argina, but is like that of "Dihivarca." Area antiquata and Area diluvii were similar enough to be confused by many of the early conchologists under the name of the former until they were separated by Lamarck. In the Deshayes and Edwards edition of the Histoire des Animaux sans Vertebres, Vol. VI, p. 470, 1835, we read that the diluvii group always has chevron-shaped grooves on the cardinal area, whereas the true antiquata never does. It is added that the true antiquata has a thicker shell, less ventricose and broader valves, with more numerous ribs. It is said further that the typical group is the most anciently known and the most common. Linnseus, Chemnitz, and others give the type locality as Jamaica, and a specimen in the Stanford collection from the West Indies agrees with Woodring's figures and with that of Chemnitz (Conch. Cab., Vol. 7, pi. 55, fig. 548) cited by Deshayes as typical, as well as with that of Reeve (Conch. Icon., Vol. 2, species 60, Area). If this is the case, we cannot say "there are no similar Tertiary or living American Areas." Furthermore, we shall have to refer all, or at least most of the forms classified by Woodring as "Diluvarca" to Area, s. s., for it does not seem practicable to separate groups on the basis of presence or absence of the cardinal grooves. Our common quadrate Areas agree in thickness of shell and number of ribs better with the typical antiquata than with diluvii, a good example being our well-known Pacific coast Area trilineata Conrad, some specimens of which are difficult to separate specifically from the type of Area, s. s. This group of forms seems to be so clear as a unit and the different species so closely related that it is hardly desirable to separate them. A separation might seriously obscure important relationships, for it does not seem probable that cardinal grooves are of phylogenetic sig- nificance. It is even likely that these grooves exist on the type of Area antiquata but are hidden by the ligament or obscured by erosion. The differences between Area antiquata and A. diluvii are, then, specific, not subgeneric or sectional. It is questionable whether Scapharea can be separated or not. Seapharea is character- ized by a thinner shell and narrower cardinal area, but grades directly into Area, s. s. Dall did not think it desirable to separate the two (that is, Seapharea and Anadara), and classed them all as Seapharea (following the practice of most American paleontologists). Europeans, on the other hand, have preferred the name Avadara for the same forms. The Adams brothers separated the two, putting the thicker shelled foinns with more obliquely elongated posterior sides into Anadara. Since Anadara is an exact synonym of Area, s. s., we have placed Scapharea in the synonymy. It might be well to state here that should Schumacher's type designation of Area antiquata Linnseus for the typical group of Ai'cas be declared invalid, then Children's designation of Area tortuosa Linnseus would probably have to be used, which would make the group here defined under Trisidos Bolten, 1798, the typical subgenus of Area. A re- striction of the name Area to the peculiar group Trisidos, represented by only one or two species, would obviously be undesirable.' ' Stewart (Special Publ. No. 'S, Acad. Nat. Sci.. Phila., pp. 34, S3, 1930) has since foxind an intermediate designation of A. nox by Schmidt, ISIS. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 139 Area (Area) multicostata Sowerby Area Willi irostata t^owerby, Proc. Zool. Soc. London for 1S33, p. 21, May 1833; Reeve, Conch. Icon., Vol. 2, Area, .sp. 23, pi. 4, fig. 23, 1844; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 134, 1S.57; Lamy, Jour. Conchyl., Vol. 55, p. 261, 1907; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, pi. 4S, fig. 1, 1907; Bull. 309, U. S. Geol. Surv., pp. 107, 152, pi. 38, same figure, 1907; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 45, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Hanna anil Hertlein, Vol. 16, p. 146, 1927. Area (Scapharca) muUicostala Sowerby, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 146. 1S94; Dall, Bull. 112, U. S. Nat. Mus., p. 16, 1921. Area (Anadara) multicoatala Sowerby, Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 71, 1895; Lamy, Jour. Conchyl., Vol. 57, p. 212, 1909. Pliocene: "Fernando" of Puente Hills, Orange County (Arnold), lower Pliocene; lower Pliocene of 3rd Street tunnel, Los Argeles (Arnold, 1907); Coronados Islands, Lower California, Mexico (Hanna and Hertlein). Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Diego, California, to Gulf of California, Mexico (Dall, 1921); Balboa, Los .\ngeles County, California (A. M. Strong, MS.). This species has a large, high shell with a somewhat rhomboid outline, moderately elevated umbones, and a large cardinal area. The sculpture consists of numerous promi- nent, flat-topped radial ribs. The anterior ribs are sometimes .slightly granulose, but the typical variety lacks the beaded ribs of variety camuloensis Osmont. Area (Area) multicostata Sowerby variety eamuloensis Osmont Plate 2, Figures .5a, 5b, 5c Area camuloensis Osmont, Univ. Calif. Publ. Geol., Vol. 4, p. 98, pi. 10, figs. 6, 6a, pi. 11, figs. 66, 6c, 1904; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 543, pi. 47, figs. 1, la, Ife, 1907; Bull. 309, U. S. Geol. Surv., p. 24, pi. 37, same figures, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 209, 1914; Kew, Bull. 7.53, U. S. Geol. Surv., p. 78, 1924. Type specimen: In the University of California collection. Type locality: Southern California; Phocene, probably near Camulos. Pliocene: Near Camulos, Ventura County; Puente Hills, Los Angeles County; foothills of Santa .\na Moun- tains, Orange County (Osmont); middle Pico of Holser Canyon, Los .\ngeles County (.\rnold; English; Kew; localities S. D. S. N. H. Nos. 217, 217a, 2l7h, coll. by H. R. Gale); middle Pico of locality 228, southeast of Pico Canyon, Los Angeles County (nine specimens, coll. by H. R. Gale). This large characteristic form has a shell sometimes as much as 8 mm. thick. The beaks are prominent and the cardinal areas high. It is distinguished from the typical Area multicostata Sowerby by the coarser ribs, which are beaded and separated by nar- rower interspaces. It may be an ecologic variety. Heavy and beaded specimens of Area trilineata Conrad occur with variety carnuloensis, suggesting that the thickness of both varieties is the result of environmental influences. Area (Area) trilineata Conrad Plate 2, Figures 1, 4 .4rc. This subgenus has generally been considered the typical group of Area because of an apparently erroneous conception of the type. It seems to be chiefly a warm-water group. Area (Navicula) terminumbonis, new species Plate 1, Figures ISo-c (Type); Figures 19a-c, 20a-c, 22 (Paratypes) Shell of medium size and thickness, elongatel.v trigonal; beaks near or at the extreme anterior end of the shell where the straight hinge line makes an acute angle with the area along the ventral margin; teeth divided near the middle by a slight internal thinning of the shell wall, outer teeth of the posterior series becoming rapidly elongated and very oblique, almost liorizontal at the end of the hinge, continuing a short distance around the corner, teeth of the anterior series showing the same tendency but to a much less degree; cardinal area higli, long, sculptured by manj^ oblique grooves; beaks twisted forward Imt not sharply overhanging as in Area noce; from the beaks an oblique fokl rumiing out to the posterior ventral corner, dividing into two broad branches as it goes, separated from the cardinal area by a depression; shell near the ventral margin of the valve nearly perpendicu- lar to the plane of the valve margins ; ventral margin arched around a very large byssal gajje ; sculp- ture consisting of many fine wavy radial striations and a few concentric ripples. Dimensions: Greatest dimension (measured along the ventral margin), 75 mm.; greatest dimension measured perpendicular to the plane of the ventral area, 32 mm. ; depth, 22 mm. ; length of hinge line, 56 mm. Type specimen: San Diego Society of Natural History, No. 79, collected from S. D. S. N. H. Loc. 207, basal Pliocene of Elsmere Canyon, Los Angeles County, California, by H. R. Gale. Pliocan-: Basal Pico of Locality 207, Elsmere Canyon, Los Angeles Co., the type and two paratypes; locality 202, Elsmere Canyon, one paratype (coll. by H. R. G.). It was at first believed that two species were represented in the specimens listed above, but it is probable that some of the differences in shape are due to a rocky habitat. The smallest specimen (pi. 1, figs. 20a-c) is very different in shape from the type specimen (figs. 18a-6), and suggests a relationship with Area pacifica. While Area terminumbonis appears to be more closely related to Navicula (group of Area iiocp) than to other subgenera, it could readily be placed in a separate section from the typical. Area merriami (Van Winkle) from the Oligocene of Washington and middle VoLUMK 1 1 Pliocene and Pleistocene Mollusca of California 143 California has the shape of Navicula and may be related; but it seems to be, in hinge characters, somewhat more like a Barbuda. It may be a connecting link or may be related to Ohliquarca Sacco. Area (Navicula) pacifica (Sowerby) Byssoarca pacifica Sowerby, Proc. Zool. Soc. Loiulon for 1833, p. 17, 1833; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus.," p. 138, 1857. Area pacifica Sowerby, Reeve, Conch. Icon., Vol. 2, Area. sp. 75, pi. 11, fig. 75, 1844; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 146, 1894; Lamy, Jour. Conchy]., Vol. 55, p. 19, 1907; Vol. 57, p. 209, 1909; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 251, 1909; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 152, 153, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 144, 1927. Pliocene: Half mile back from the shore at Santa .\ntonita Point, Lower California, Mexico (Hamia and Hert- lein). Pleistocene: Upper Quaternary of Scamraons Lagoon, west coast of Lower California, Mexico (Jordan); upper Pleistocene, coast of Oaxaea, Mexico (collected by R. H. Palmer). Recent: Scammons Lagoon, Lower California, Mexico, to Tumbes, Peru (Jordan). This species has a much deeper and more coarsely sculptured shell than A. terminum- bo7iis, new species. Reeve has a good figure of it. Subgenus BARBATIA Gray, 1847 Barbatia Gray, Synopsis of the Contents of the British Museum, Ed. 42, p. 151, 1840, 7iomen nudum; Proc. Zoo!. Soc. London "for 1847, p. 197, 1847; H. and A. Adams, Gen. Rec. Shells, Vol. 2, p. 534, pi. 124, figs. 4, 4a-b, 1857; Dall, Trans. Wagner Inst., Vol. 3, p. 614, 1898; Woodring, Carnegie Inst. Publ. No. 366, p. 33, 1925; Gard- ner, U. S. Geol. Surv., Prof. Paper 142A, p. 25. 1926. Type (by original designation, Gray, 1847), Area barbata Linnaeus, Mediterranean; Recent; figured by Reeve, Conch. Icon., Vol. 2, Area, sp. 83, pi. 13, fig. 83, 1844. According to Gray, Barbatia is distinguished by the lengthening and the increasing obliquity of the teeth from the center to the ends of the hinge line, and by the hairy (bearded) epidermis. It is usually a comparatively small, not very thick shell with some- what irregular fine radial striations and a narrow cardinal area. It is elongate-quadrangu- lar in outline, with the corners well rounded, and usually has only a narrow byssal gape. Area (Barbatia) reeviana d'Orbigny "Area helblingvi Bruguiere," Reeve, Conch. Icon., Vol. 2, Area, sp. 90, pi. 14, fig. 90, 1844, not Area helhlingii Bruguiere, Ency. Meth. Vers, Vol. 1, p. 99, 1789, fide Dall, 19G9. Area reeviana d'Orbigny, Voy. Amer. Merid., p. 635, 1846, fide Dall, 19C9; in Ramon de la Sagra, Hist. Cuba, Moll., Vol. 2, p. 320, 1853, ^rfe Lamy, 19C9; Carpenter, Brit. Assn. Adv. Sci., Rept. for 18.56, p. 278, 1857. Byssoarca reeviana d'Orbigny, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 147, 1894. Area {Barbatia) reeviana Orbigny, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 2.52, 1909. Area reeviana Orbigny, Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 140, 1927. Pliocene: Carmen Island, Lower California, Mexico, coll. by Dr. Fred Baker (Hanna and Hertlein). Recent: Lower California, Mexico, to Peru and Galapagos. There have been reports of finding this species at Balboa, Los Angeles County, California. Area (Barbatia) reticulata Gmelin Area reticulata Gmelin, Syst. Nat., Ed. 13, Vol. 1, p. 3311, 1790; Chemnitz, Conch. Cab., \i>\. 7, p. 193, pi. .54, fig. 540, 1784. ? Area plicata Chemnitz, Conch. Cab., Vol. 11, p. 244, pi. 204, fig. 2008, 1795. Area gradata Broderip and Sowerby, Zool. Journal, Vol. 4, p. 365, 1829; Gray, Zool. Beechey's Voy., Moll., p. 152, pi. 43, fig. 1, 1830; Reeve, Conch. Icon., Vol. 2, Area, sp. 92, pi. 14, fig. 92, 1844; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 252, 1909; Woodring, Carnegie Inst. Publ. No. 366, pp. 36, 37, 1925. 144 San Diego Society of Natural History [Memoirs ? Byssoarca divaricata Sowerby, Proc. Zool. Soc. London for 1833, p. 18, 1833; Reeve, Conch. Icon., Vol. 2, Area, sp. 108, pi. 16, fig. 108, 1844. Byssoarca gradata Broderip and Sowerby, Carpenter, Cat. Reigen Coll. Mazatlan MoU. Brit. Mus., p. 141, 1857; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 147, 1894. Barbatia (Aca.r) reticulata Gmelin, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 629, 1898. Area (Aear) plicaia Chemnitz, Lamy, Jour. Conchyl., Vol. 55, p. 81, 1907; Vol. 57, pp. 210, 211, 1909. Barhalia reticulata Gmelin, Dall, BuO. 112, U. S. Nat. Mus., p. 16, 1921. Area (Barbatia) reticulata Gmelin, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 45, 1924. Pleistocene: Upper Pleistocene, coast of Oaxaca, Mexico (collected by R. H. Palmer). Recent: San Pedro, California, to Ecuador (Oldroyd); Monterey ? (Berry); also Caribbean. Chemnitz (1784) stated that he could not give the habitat of A. reticulata, but that he beheved it came from the West Indies. According to Woodring (1925) Kobelt' stated that the shell figured by Chemnitz as Area retieulata came from the Indian Ocean. This might be an error on the part of Kobelt. Woodring points out that "the figure does not resemble the West Indian Area that goes under the name of reticulata." Dall, in his Wagner Institute Memoir on the Florida Tertiary (p. 629, 1898), considered reticulata and gradata con-specific, the latter having been described from Mazatlan, west coast of Mexico. Dall likewise considered A. divaricata Sowerby, 1833, as an additional synonym, although divaricata supposedly came from the East Indies. Under the circumstances we have tentatively considered A. retieulata Gmelin and A. gradata Broderip and Sowerby synonymous, perhaps representing a single species occurring on both Atlantic and Pacific coasts of America. Woodring (1925) designated A. gradata as type of Acar Gray," a minor subdivision of Barhalia with reticulate sculpture. Subgenus TRISIDOS Bolten, 1798 Trisidos Bolten, Mus. Bolt., p. 175, 1898, only species Area lortiio^a. Linnseus. This is Trisis Oken, 1815, and Parallelepi pedum (Klein) H. and A. Adams, Dec, 1857, both of which have the same type. It is a peculiarly twisted Area with a long hinge line and much reduced cardinal area, now living in India and China. Children (1823) cited A. tortuosa as the type oi Area. Hence, if Schumacher's prior type designation is disregarded, this peculiar group might become typical Arca.^ Superfamily Pteriacea Family PINNIDAE Shell mytiliform, not alate, with two adductor muscles, the anterior smaller; valves equal, truncate, and whoOy open behind; hinge without teeth; cardinal area linear; ligament internal; byssus present; shell structure coarsely prismatic, the unier layer thimier and nacreous. The family dates from the Paleozoic, Palceopinna Hall of the Devonian and Avi- culopinna Meek of the Carboniferous and Permian being the early representatives of the group. The shell of the Pinnidce is made up partly of very coarse prisms like Inoceramus, the inner pearly layer readily splitting away when dessicated. Genus PINNA Linnasus, 1758 Pinna Linnseus, Syst. Nat., Ed. 10, p. 707, 1758, list includes P. muricata, P. rudis, and others; Children, Quart. Jour. Sci. Lit. Arts, Vol. 15, p. 34, pi. 1, fig. 80, April, 1823, type Pinna rudis Lirmseus; Gray, Proc. Zool. Soc. London for 1847, p. 199, 1847, type Pinna rudis Lmnseus. ' Syst. Conch. Cab. Martini und Chemnitz, Band 8, Abtheilung 2. Area, p. 211, 1891. '■ Ann. Mag. Nat. Hiat., Ser. 2, Vol. 19, p. 369, 1S57. > Schmidt's designation is somewhat questionable. See note on Area. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 145 Type (by absolute tautonymy), Concha -pinna Hasselquist = Pinna muricata Lin- naeus, 1758; habitat, East Indies (see discussion below). Shell equivalve, wedge-shaped, with umbones at extreme end, which is acute; posterior (ventral) side truncated and gapmg; ligamental groove long, linear; anterior adductor scar apical, posterior scar subcentral, large and ill-defined; pedal scar in front of posterior adductor. Children (1823) and Gray (1847) both cited Pinna rudis L. as type, but Linnaeus (1758) gave "Concha Pinna" Hasselquist as a synonym of Pinna muricata and according to the International Rules of Zoological Nomenclature^ muricata becomes the type by absolute tautonymj^ It appears that Linnaeus wrote the names for Hasselquist (1757), so the "Pinna" of Concha Pinna was properly used as a specific name. There has been doubt about the recognition of Pinna muricata Linnaeus. Reeve- figures what, "according to Chemnitz and Lamarck, appears to be the Linnaean P. muricata" but gives the habitat as West Indies. Chemnitz, ^ who studied the species critically, attributes it to the "Ostindischen Meeren" and Reeve seems to have translated this as West instead of East Indies. Rumphius, according to von Born^ reported it from Amboyna, which is in the Moluccas, and although Lister attributed it to the Mediterran- ean, we believe the latter to be an error. There are several named forms of Pinna in the Indo-Pacific region which fit the original description of muricata and likewise the figures of Chemnitz and Reeve. One of these should be selected by the first reviser as the Lin- naean muricata. Dall^ has expressed the opinion that the true muricata is an Oriental species, but he does not attempt to settle the difficulty. However, the uncertainty does not disturb the present conception of the genus, for all of the species of which the Lin- naean muricata is one, appear to belong to the same group as P. rudis. Subgenus PINNA, s. s. Shell elongate, with a longitudinal crack or sulcus filled with cartilage in the middle of each valve. The Atrinas are generally shorter and broader than the true Pinnas and lack the longitudinal medial sulcus which sometimes tends to give fossil Pinnas a subangular cross-section. Pinna (Pinna) latrania Hamia Pinna latrania G. D. Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 475, pi. 27, fig. 1, text fig. 1, March 23, 1926. Shell thin, long and slender, apical angle acute (27°); surface apparently unmarked externally by ridges, ribs, or spines, except for a heavy longitudinal mid-rib in each valve, the mid-rib Ijeing rounded, convex internally, apparently sharply carinate externally, and divitled longitutlinally, the two parts being united by cartilage; the length of this rib unobtahiable from available material, but h\ other species it does not extend entirely to the beak; each valve deeply sulcate at the mid-rib so that in looking dowTi upon it, it is double-loojjed. Length of type specimen, 1.35 mm.; width from hinge line down, 63 mm.; gape posteriorly, 51 mm.; length of hinge line, 116 mm.; length of byssal scar, 85 mm. (Hanna.) Type specimen: In U. S. National Museum, No. 324,593. Plaster cast in California Academy of Sciences. Type locality: Coyote Mountain, Imperial County, California; Pliocene. Pliocene: At the head of Garnet Canyon on the north side of Coyote Mountain, Imperial County, California (Hanna). 1 See Article 30d, and Opinion 16. The Rules and Summaries of Opinions were republished in Proc. Biol. Soc. Wash., Vol. 39, pp. 75-103. July 30, 1926. » Conchologia Iconica, Vol. 11, Pinna, pi. 13, fig. 23, May, 18.5S. 8 Neues Systematisches Conchylien Cabinet, Vol. 8, pp. 235-236, 1785. ^ Testacea Musei Caesarei Vindobonensis, p. 133, 1780. ' Trans. Wagner Inst. Sci., Vol. 3, p. 661, 1898. HG San Diego Society of Natural History [ Memoirs Pinna (Pinna) mendenhalli Hanna Pinna rmndenhnlli Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 47(), pi. 27, fig. 2, March 23, 1926. Type specimen: In U. S. National Museum, No. 324,593, the same number as for the preceding species. Type locality: Coyote Mountain, Imperial County; Pliocene. Pliocene: At the head of Garnet Canyon, on the north side of Coyote Mountain, Imperial County, California (Hanna). This is a thick and heavy species with an apical angle of 47°. It has the mid-rib, which places it in the subgenus Pinna. Subgenus ATRINA Gray, 1840 Airina Gray, Synops. Cont. Brit. Mus., Ed. 42, p. 151, 1840; Ed. 44, p. S3 1842, fide Iredale, Proc. Malac. Sec. Lon- don, Vol. 10, p. 3C3, 1913; Gray, Proc. Zool. Soc. London, 1847, p. 199, 1847. Type (by subsequent designation. Gray, 1847), Pmna nigra Chemnitz, Indo-Pacific; Recent. Shell shorter than that of Pinna, s. s., and without the longitudinal medial sulcus. Pinna (Atrinaj alamadensis Yates Pinna alamade7(si^ Yates, in Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 2.59, footnote, 1888. Pinna alainedeiisin Yates, Cooper, Calif. St. Mining Bureau, Bull. 4, pt. 5, p. 56, pi. 4, fig. .53, 1894; Clark, Univ. Calif. Publ. Geol., Vol. 8, pp. 420, 440, 447, pi. 48, fig. 3, 1915; Nomland, Vol. 10, pp. IBOl, :302, 30S, 1917. Pinna (Airina) alamedensis Yates, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 665, 1898. ? Pinna venlurensis Yates, in Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 259, footnote, 1888; Cooper, Calif. St. Mining Bureau, Bull. 4, pt. 5, p. 56, pi. 4, fig. 54, 1894. ? Pinna (Airina) venlurensis Yates, Dall, Trans. Wagner In.st. Sci., Vol. 3, p. 665, 1898. This species has nine concentric, inequidistant, rounded wrinkles emanating from the open side, and turning towartl the hinge nearly at right angles, the entire shell marked by small longitudinal narrow ribs (about forty), which, radiating from the apex, extend to the basal margin, liecoming more indistinct as they approach the lower margin. These ri})s at their intersections with the lines of growth are ornamented by slight elevations forming zigzag markings along the lines of growth. The hinge is straight the entire length, the oijposite side running parallel for about half the distance from base to apex, where it makes a sharp curve, ami continues at an angle of about forty-five degrees to the apex. Length nine, width five, and thickness about two inches. (Yates.) Type localities: Of alamadensis, Alameda Creek, Alameda County, Miocene; of venlurensis, Casitas Pass, Ventura County, Miocene. Miocene: Vaqueros, lower Miocene, at Casitas Pass; Monterey-Temblor, middle Miocene (Nomlantl); upper San Pablo, upper Miocene (Clark). Pinna venlurensis Yates may be conspecific. Clark (1915) reported alamadensis as very common in the San Pablo Miocene, where it attains a length of ten inches and a maximum width of about five and a half inches. Pinna (Atrina) bicuneata Nomland Pirma binineata Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 301 (list), 308, pi. 15, figs, la-b, November 8, 1917. Shell elongate-cuneate; in cross-section thin, acutely elliptical. Hinge line long, nearly straight ; ventral margin slightly concave near beaks; posterior end evenly rounded. Sculptured by approxi- mately ten distinct raiHating ridges which appear to be alisent on lower one-third of shell. Length, 96 mm.; width, 44 mm.; thickness, 18 mm.; umljonal angle, 35 degrees. (Nomland.) Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 147 Type specimen: University of California, No. 11,307. Type locality: Ten miles northeast of Coalinga, upper Miocene. Miocene: Santa Margarita formation, near Coalinga; upper San Pablo formation, Las Trampas Ridge, Concord Quadrangle, Contra Costa County (Nomland). ? Pliocene: Near Standard Oil Company, Powell well, eight miles northeast of Bradley, Monterey County, possibly lower Etchegoin ? (Nomland). There are several other Pinnas in the earlier Tertiary. In the California Recent fauna there is but one known species, Pinna (Atrina) oldroydi Dall'. Mr. Frank Stephens, of San Diego, reports a Pinna in the Pleistocene deposits along the coast of San Diego County, but the specimens have not yet been studied. Family PTERIIDAE Shell oblique, Aviculoid, alate, inequivalve, adult with one adductor scar; ligament aliviiieular; byssus present; young with hinge teeth, becoming obscure with ago. This family dates from the middle Paleozoic and includes such well-known extinct genera as Pseudomonotis Beyrich (Devonian to Cretaceous), Monotis and Halobia Bronn, and Daonella Mojsisovics (Triassic). It is somewhat intermediate between the dimy- arians and the monomyarians, the young possessing two adductor muscles, the anter or becoming very small or absent in the adult. Genus PTERIA Scopoli, 1777 Pleria Scopoli, Introd. Hist, natur. p. 397, 1777, sole species Mytilus Jiiruiitlo Linnseus; Meek, I'. S. Geol. Surv. Terri- tories, Vol. 9, pp. 28, 29, 187t); Dall, Trars. Wagner Inst. Sci., Vol. 3, p. 668, 1898. Aviculn Bruguiere, Enc. meth. Vers, Vol. 1, fasc. 2, p. 536, 1792; Children, Quart. Jour. Sci., Lit., Arts, p. 37, 1823, type cited Ai'icula crocea Lamarck. Type (by monotypy), Mytilus hirundo Linnseus, figured by Bucquoy, Dautzenberg and Dollfus, Moll. Mar. Roussillon, Vol. 2, fasc. 4, pi. 22, 1890, Mediterranean; Recent. Shell oblique, inequivalve, eared, hyssal notch present under anterior ear of right valve; cardinal area linear, with obscure or obsolete teeth; dorsal margin long, straight; sculpture not prominent; shell fragile. Subgenus PINCTADA Bolten, 1798 Margaritifera P. Browne, Civil and Natural History of Jamaica, second edition, p. 412, 1789; Harris, Cat. Tert. Moll. Brit. Museum, Pt. 1, p. .32.5, 1897; Jameson, Proc. Zool. Soc. London for 1901, Vol. 1, p. 372, 1901. Pinctada Bolten, Mus. Boltenianum, p. 166, 1798, first species, P. margaritifera: Iredale, Proc. Malac. Soc. London, Vol. 11, p. 305, 1915. Vnionium Link, Beschr. Rost. Samml., Abth. 3, p. 155, 1807, fide Harris. Margariiiphora Megerle, Mag. Gesellschaft Naturforschender Freunde, Berlin, Jahrgang 5, p. 66, 1811; type ^1/. communis = M. margaritifera Linnseus, yif/c Jameson; "Margnrilophora" of L. Agassiz, Xomen. Zool., Index Univ., 1846, emend, pro. Margariiiphora Megerle. Margarita Leach, Zool. Misc., Vol. 1, p. 107, 1814, t5-t)e M. sinensis Leach = M. margaritifera Linnaeus, China; not Margarita Leach, 1819. Perlamatcr Schumacher, Ess. Nouv. Syst. Hab. Vers, Test., p. 107, 1817. Meleagrina Lamarck, Anim. s. Vert., Vol. 6, p. 150, 1819; not Lamarck, 1812, vernacular use. Type (by subsequent designation, Iredale, 1915), P. margaritifera (Linnseus), Oriental seas. Shell less oblique than in Pteria, s. s., valves flatter and nearly equal; posterior ears or hinge con- tinuation smaller or entirely absent; pedal impression blended with that of the atlductor; shell pearly within. ' Nautilus, Vol. 14, p. 143. 1901; figured in Bull. 112, U. S. Nat. Mus.. pi. 2. figs. 4. .5, 6, 1921, .and by Oldroyd. Stanford Univ. Publ. Geol. Vol. 1, pi. 28, fig. 12, 1924. Range San Pedro Bay to San Onofre. southern California. 148 San Diego Society of Natural History [Memoirs The pearl-oysters have long been known under the name of Margaritifera. This name was proposed by Patrick Browne in the "Civil and Natural History of Jamaica," the first edition of which was pre-Linnsean (1756), and the second has been declared nomenclator- ially invalid under suspension of the rules by Opinion 89 of the International Commission on Zoological Nomenclature. Margaritifera of Humphrey in the Museum Calonnianum (p. 44, 1797) is likewise invalid. Pindada Bolten is the earliest name that can be used for the group, and should the Museum Boltenianum be rejected, Uniotiium Link, 1807, is next in order. There are at least three other names available earlier in date than La- marck's Meleagrina, which was first published as a generic name in 1819, his use of it in 1812 being in the vernacular. The pearl-oysters have been of commercial importance on the west Mexican coast and in the Panamic region for many years. In addition to the single species listed below, Pteria (Pindada) fimbriaia Dunker (1852, not Reeve, 1857) occurs in the Gulf of Califor- nia. The Pteria vivesi de Rochebrune, 1895, is a Pteria, s. s., and a synonym of P. peruviana Reeve in the Iconica, 1857. Pteria (Pinctada) mazatlanica (Hanley) Margaritiphora mazatlanica Hanley, Cat. Rec. Biv. Sliells, p. 388, pi. 24, fig. 40, 1855. Avicula barbata Reeve, Conch. Icon., Vol. 10, Aiicula, pi. 5, fig. 9, 1857. Meleagrina mazatlanica Hanley, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 564, 576, 1864. Meleagrina margaritifera Linnaeus, Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 72, 1895. Pteria {Margaritifera) margaritifera L. var. mazatlanica Hanley, Jameson, Proc. Zool. Soc. London for 1901, Vol. 1, pp. 376, 377, 1901 ; Lamy, Jour. Conchyl., Vol. 57, p. 227, 1909. Margaritifera mazatlanica Hanley, Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, pp. 141, 146, 150, 1927. Pliocene: Southwest point of Coronados Island; also on Ceralbo Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Gulf of California to Panama. Jameson, whose excellent paper, "Mother-of-Pearl Oysters," is referred to above, considered P. mazatlanica an unusually convex and aberrant variety of P. margaritifera Linnseus, the typical form of which appears to belong to the warm western Pacific. The posterior angle of mazatlanica is acute or rarely a right angle; the anterior margin below the byssal notch "projects further forward than in any other variety, so that a perpen- dicular to the hinge from its anterior end would cut off about M of the valve. "' Recent specimens are of a grayish yellow or light brown color; the radial rows of spots are very indistinct, and approximate the ground color of the shell. The inner sui'face of the valve has a yellowish brown lip, the nacreous portion being of a silvery white with a golden or brassy margin. ? Family PHILOBRYIDAE Genus PHILOBRYA Carpenter, 1872 Bryophila Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 314, April, 1864; Tryon, Struct. Syst. Conch., Vol. 3, p. 284, 1884; not Bryophila Trietschke, in Ochsenheimcr, Die Schmetterlinge von Europa, ^'ol. 5, p. 57, 1825, Lepidoptera. Philobrya Carpenter, Smithsonian Miscellaneous Collections, Publication No. 252, Inde.x, p. 21, substitute name for Bryophila. Type (by monotypy), Bryophila setosa Carpenter. Shell like that of a minute Pinna with pointed beaks ; upper margin straight, with a strong in- ternal ligament, anteriorly somewhat indented by the tjyssal sinus, ventrally and posteriorly rounded and gaping; posterior muscular scar subcentral, indistinct. (Tryon.) 1 Jameson, he. cit. VoLtTME I ] Pliocene and Pleistocene Molltjsca of California 149 The generic name Bryophila having been preoccupied, Carpenter proposed in the index to the Smithsonian Reprint of his "Supplementary Report" the name Philobrya as a substitute. The single species appears to be closely related to the Pinnida, the shape and shell structure being like that of Pinna. Philobrya setosa (Carpenter) Bryophila setosa Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 314, April, 18G4; Brit. Assn. Adv. Sei., Rept. for 1863, pp. 538, 612, 618, 645, 1864; Bernard, Journ. de Conchy!., Vol. 45, p. 10, text figures 1, 4, pi. 1, fig. 1, 1897. Philobrya setosa Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 17, 1921; I. S. Oklroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 48, pi. 54, figs. 32 to 35, 1924. Type specimen: In U. S. National Museum. Type locality: Cape San Lucas, Lower California; Recent. Pleistocene: San Pedro cut, Los Angeles County (T. S. Oldroyd collection). Recent: Forrester Island, Alaska, to Gulf of California, Mexico (Dall). Superfamily Ostracea Shell sessile, inequivalve, often irregular, sometimes very heavy, not auriculate, without gape; composed of subnacreous or porcellanous and prismatic shell layers; hinge edentulous or with de- generate schizodont teeth. Geologic range: Carboniferous to Recent. Family OSTREIDAE Shell distorted by sessile habit; only the posterior adductor muscle present in the adult; generally attached by the left valve, which may be more ventricose than the right. Genus OSTREA Linnaeus, 1758 Oslrea Linuajus, Syst. Nat. Ed. 10 p. 696 1758; Muller Prodr. Zool. Daniea pp. x.\xi and 247, 1776; Children, Quart. Jour. Sci., Lit., Arts, Vol. 15, p. 44, pi. 2, fig. 94, April, 1823; Meek, U. S. Geol. Surv. Territories, Vol. 9, p. 10, 1876. Type (by subsequent designation, Children, 1823), Ostrea edulis Linnseus, figured by Reeve. Shell irregular, with termmal beaks; sculptured by imbricating lamelliB and plications, or rarely almost smooth ; lower valve generally deeper than upper valve, which may be flat or externally con- cave; ligament in a mesial groove. In view of a forthcoming report on the Pacific coast Neocene subgenera and species of Ostrea, the treatment of the group here will consist of a mere chronological listing of the Pliocene and Pleistocene species. Ostrea calif omica Marcou Ostrea virginica var. californica Marcou, Geology of North America, p. 32, pL 5, figs. 2, 2a, Zurich, 1858; Hanna and Hertlein, Nautilus, Vol. 41, p. 46, Oct. 1927. "Ostrea iridescens Gray," Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 468, pi. 26, figs. 4-7, 1926; not of Gray, MS., Hanley, Conch. Misc., Ostrea, pi. 2, figs. 6, 7, 1854. Pliocene: Coyote Mountain, Imperial County (Hanna, 1926). Hanna and Hertlein (1927) state that the Coyote Mountain form referred by Hanna (1926) to 0. iridescens Gray is exactly like Marcou's figures of californica. The Recent west Mexican Ostrea which Carpenter, Dall, and others have referred to "Ostrea iridescens 150 San Diego Society of Natural History [Memoibs Gray" appears to be a synonjm of Oslrea prismaUca Gray'. In spite of Ball's remarks (Nautilus, Vol. 28, p. 1, 1914), the present authors believe the name iridescens should be dropped in favor of prismatica Gray, 1825, for the Gulf of California Recent species. Ball's discussions of oysters have never been satisfactory. Ostrea megodon Hanlcy Oslrea megodon Hanley, Proc Zool. Soc. of London for 184.5. p. 106, 1846; Sowerby, in Reeve's Conch. Icon., Vol. 18, Ostrea, sp. 24, pi. 12, figs. 24o-b, 1871; Dall, Trans. Wagner In.st. Sci., Vol. 3, p. 685, 1898; Nautilus, Vol. 28, p. 1, 1914; Dall, in Orcutt, West American Scientist, Vol. 19, p. 23, 1921; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 1.5, p. 244, 1926; Jordan and Hertlein, Vol. 1,5, pp. 427, 428, pi. 28, fig. 1, 1926; Hanna and Hcrt- lein, Vol, 16, p. 141, 1927. ? Ostrea gallus Valenciennes, Voy. Venus, Coq., pi. 21, 1846, fide Dall, 1898. Oslrea cerrosensis Gabb, Geo!. Surv. Calif., Pala-c, Xo\. 2, p. 3.5, 1866; p. 106, pi. 11, fig. 61, 1868-9. Pliocene: Cedros Islard, vicinity of Turtle Bay, Loreto, San Antonio Point, Maria Madre Island, Santa An- tonita Point, all in Lower California, Mexico (Jordan and Hertlein; Hanna and Hertlein) ; "Saugus" near Piru, Santa Clara Valley (Jordan and Hertlein). Pleistocene: San Quintin Bay, west coast of Lower California, Mexico (Dall, in Orcutt; Jordan). Recent: Lower California south to Peru (Dall, 1914). This species is nearly equivalve, of a reniform shape, and has large rounded plications which give the ventral margin great resistance against lateral thrusts. Ostrea megodon has been reported from the Burabo formation of the Bominican Republic by Maury, from the Miocene of Bowden, Jamaica, by Ball (1898), and from the Miocene of Costa Rica by Olsson; but Woodring (Carnegie Inst. Publ. No. 366, p. 60, pi. 6, figs. 12-14, 1925) points out differences in the Bowden form, which he renames paramegodon. The Carib- bean species, however, appears to be closely related. Ostrea cumingiana Dunker Ostrea cumitigiaiia Dunker, Zeitsthrift f. Malak., Vol. 3, p. 48, 1846; Philippi, Abbild. Conch., Vol. 2, Ostrea, p. 81, pi. 1, figs. 1-4, 1846; Carpenter, Brit. A.=sn. Adv. Sci., Rept. for 1856, p. 352, 1857. Ostrea jacobea de Rochebrure, Bull. Mus. Hist. Nat. Paris, Vol. 1, p. 241, 1895; not of Linnseus, Syst. Nat. Ed. 10, p. 696, 1758; Ed. 12, p. 1144, 1767. Ostrea sinensis var. cumingiana Dunker, Lamy, Jour. Conchyl., Vol. 57, pp. 218, 219, 1909. Ostrea fischeri Dall, Nautilus, Vol. 28, p. 1, 1914, new name for 0. jacobea de Rochebrune, not Linnaeus; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 141, 1927. Pliocene: Espiritu Santo Island, Lower California, and Ceralbo Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Gulf of California and west coast of Mexico. Lamy (1909) considered this oyster a variety of Ostrea sinensis Gmelin (Syst. Nat., Ed. 13, Vol. 1, p. 3335, 1790).= This latter species appears to be similar to "Mytilus" hyotis Linnaeus but does not have tubular spines. Authentic specimens or the type of Ball's 0. iubulifera should be carefully compared with Ostrea hyotis (Linnseus). Ostrea amara Carpenter, 1857, 0. angelica de Rochebrune, 1895, and 0. mexicana Sowerby, 1871, should be compared with cumingiana Bunker, 1846. ' Ann. Philos., Ser. 2, Vol. 9. p. 139, 1825; Hanley. Cat. Rec. Biv. Shells, p. 302, 1842; Sowerby. in Heave's Conch. Icon.. Vol. IS. Ostrea. sp I, pi. 1. 1871; Lamy, Journal de Conchyliologie, Vol. 57, p. 219, 1909. According to Lamy, Ostrea lucasiana de Rochebrune (Bull. Mus. Hist. Nat. Paris, Vol. 1. p. 241, 1895) is a further synonym of prismatica Gray. Sowerby, in Reeve, has a fine figure of prismaUca. of which he considers iridescetts a synonym. ' Figured by Hanley, Conch. Misc., Oslrea. pi. 3. figs. 9-12, 18.54, and by Sowerby in Reeve's Conch. Icon., Vol. 18, Ostrea. pi. 3, fig. 5, 1870. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 151 Ostrea heermanni Conrad Ostrea hedrmanni Conrad, Proc. Acad. Nat. t-'ci. Pliila., Vol. o, p. 267, 1855; U. S. Pacific R. R. Repts., Vol. 5, p. 326, 1855; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 685, 1898, his Carrizo Creek localities onlj', not his other localities nor his SJ^lonymy. Ostrea heermani Conrad, Kew, Univ. Calif. Publ. Geol., Vol. 8, p. 46, 1914. Ostrea heermanni Conrad. Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 467, pi. 22, figs. 7, 8, jil. 23, figs. 1, 2, 1926. Pliocene: Carrizo Creek region (Conrad); Carrizo formation, lower division, all localities, upper division at Yuha Buttes, western Imperial County (Kew); abundant in many places in the Imperial formation of Coyote Mountain, western Imperial County (Hanna). (!. D. Hanna appears to be the only one who has figured this early described Cali- fornia species. He remarks: "Although this species has not been previously figured, so far as I have been able to determine, there is no mistaking the fact that Conrad had specimens of the only large circular oyster of the Coyote Mountain region. It is exces- sively abundant in many places and also excessively variable." (Hanna, 1926.) Ostrea lurida Carpenter Ostrea lurida Carpenter, Brit. Assn. Adv. Sci., Rept. for 1S63, p. 645, 1864; Jour. Conchyl., Vol. 12, p. 137,^1865; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 106, 1869; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 256, 1888; Keep, West Coast Shells, p. 164, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 193, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 102, 1903; U. S. Geol. Surv., Bull. 396, p. 167, pi. 30, fig. 12, Jan. 15, 1910; .\rnold and .\nderson, Bull. 398. p. 1.53, pi. 52, fig. 12, 1910; Clark, Univ. Calif. Publ. Geol., Vol. S. p. 419, 1915; Martin, Vol. 9, p. 253, 1916; Nomland, Vol. 10, p. 219, 1917; Weymouth, Calif. Fish and Game Comra., Fish Bull. No. 4, p. 24, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 18, 1921; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. .563, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 50, pi. 37, figs. lOa-6, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, .\rt. 22, p. 3, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ, Geol., Vol. 18, p. 78, 1929; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 251, 2.52, 255, 1929. Type specimen: In U. S. National Museum. Type locality: Vancouver Island; Recent. ? Micoene: San Pablo formation of middle California (Clark, 1915). Pliocene: Uppermost Etchegoin formation of Coalinga district (Arnold); common in the Pecten coalingensis and Mya japoiiica zones of Coalinga (Nomland); ''Pico" near Ventura (Waterfall); Cedros Island and Turtle Bay, Lower California, Mexico (Jordan and Hertlein); upper Merced south of San Francisco I Martin). Pleistocene: Rare in the lower San Pedro series of Deadman Island and San Pedro (.\rnold) ; Pleistocene of Benecia, Solano County {fide Arnold, 1903); Tomales Bay, Marin County (Dickerson); lower San Pedro of Nob Hill cut, San Pedro (Oldroyd, 1925); "Saugus" formation near Ventura (Waterfall); foot of 26th Street, San Diego (Arnold, 1903; Stephens); Greeley Street; east side of Point Loma, common; two miles north of Del Mar; northeast end of Point Loma, all San Diego County (Stephens); e.xceedingly common in upper San Pedro series of San Pedro, Signal Hill, and Long Beach, Los Angeles County (Arnold, 1903) ; upper Pleistocene of San Quintin Bay, Lower California, Me.xico (Jordan). Recent: Sitka, Alaska, to Cape San Lucas, Lower California, Mexico (Dall, 1921). This is a rather small species of an irregular ellipsoidal or elongate shape, sculptured with crude, low, irregular plications, or almost smooth except for irregularities of growth. The layers of the fossil shells are often easily scaled off if leaching has weakened the na- creous shell structure. It is very abundant at certain places. It has not been generally recognized from the Miocene ; and the San Pablo formation record might have been based upon the young of some other species. 152 San Diego Society of Natural History [Memoirs Ostrea palmula Carpenter Ostrea ? ? conchapkila, var. pahnula Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., pp. 163, 550, 1857. Ostrea -palmula Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. IS, 1921; I. S. Oldroycl, Stanford Univ. Publ. Geol., Vol. 1, p. 51, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 148, 151, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. IS, p. 7S, 1929. Pliocene: "Pico" near Ventura (Waterfall). Pleistocene: Lower Quaternary of Magdalena Bay and upper Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan) ; Santa Rosalia district, gulf side of Lower California, Mexico (collected by M. E. Touwaide). Rece7U: Puget Sound to Gulf of California (Dall, 1921). 0. palmula has palm-like foliations on the outer margin, and a row of denticles which fit into the margin of the opposite valve. It is a small species, about two or two and a half inches long (50 or 60 mm.). Lamy' stated that this species may be identical with 0. spathulata Lamarck-. Ostrea vespertina Conrad Plate 12, Figures la, lb Ostrea vespertina Conrad, Jour. Acad. Nat. Sci. Phila., Ser. 2, Vol. 2, p. 300, 1854; U. S. House of Representatives, House Doc. No. 129, p. 15, July, 1855; U. S. Pacific R. R. Repts., Vol. 5, p. 325, pi. 5, fig.s. 36-8, 1856, re- printed by Dall, U. S. Geol. Surv., Prof. Paper 59, p. 168, 1909; Gabb, Geol. Surv. Calif., Palso., Vol. 2, p. 107, 1869; Arnold, U. S. Geol. Surv., Bull. 396, p. 77, pi. 24, figs. 4, 5, 1910; Bull. 398, pi. 46, same figures, 1910; Kew, Univ. Calif. Publ. Geol., Vol. 8, p. 46, 1914; English, Vol. 8, p. 210, 1914; Nomland, Vol. 10, pp. 219, 299, 300, 302, 1917; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, pp. 468, 469, pi. 26, figs. 1, 2, 3, 1926; Jordan and Hertlein, Vol. 15, pp. 212, 428, 429, 1926; Hanna and Hertlein, Vol. 16, p. 141, 1927. ? Ostrea amara Carpenter, Proc. Zool. Soc. London for 1863, p. 363, 1863. Ostrea veatchii Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 34, pi. 11, fig. 59, 1866; Dall, Seventeenth Ann. Rept., U. S. Geol. Surv., Pt. 1, p. 844, 1896; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 63, questionably identified, 1903; Proc. U. S. Nat. Mus., Vol. 32, pp. 527, 544, pi. 49, fig. 1, 1907; Weaver, Wash. Geol. Surv., Bull. 15, p. 18, 1912; Dall, Nautilus, Vol. 28, p. 1, 1914; Vol. 32, p. 24, 1918; U. S. Nat. Mus., Bull. 112, p. 17, 1921; Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 49, 1926. Miocene: Blakely formation, "lower Miocene" of western Washington (Weaver); Alka Island and Unga Island, Alaska (Dall, 1896); Santa Margarita, U])per Miocene, north of Coalinga and questionably of the Tejon Hills, also San Pablo formation, upper Miocene, of middle California (Nomland, 1917). Pliocene: Lower Fernando of Holser Canyon (English); lower Pliocene of Third Street Tunnel, Los .\ngeles (Arnold, 1907); lower Fernando of Fugler's Point, Santa Barbara County (Carson); Etchegoin for- mation of Coalinga district (Arnold); common in Pecten coalingensis and Mya japonica zones of Coalinga district Pliocene (Nomland, 1917); Imperial formation of Coyote Mountain, western Im- perial County (Kew; Hanna); questionably. Pliocene of Russ School and Pacific Beach, San Diego (Arnold, 1903) ; Pico formation of southern California (Jordan and Hertlein) ; Cedros Island, Turtle Bay, and Elephant Mesa, west coast of Lower California (Jordan and Hertlein); Santa Antonita Point, Loreto, Coronados Island, Pond Island, San Jose Island, all Lower California, Mexico (Hanna and Hertlein); upper Pliocene of Maria Madre Island, Lower California (Jordan and Hert- lein); very- abundant in the normal facies of the middle Pliocene from Fernando Pass to Holser Canyon, Los Angeles County, S. D. S. N. H. localities 213, 214, 228, 268, 217, etc. (H. R. G.) Pleistocene: Magdalena Bay, west coast of Lower California, Mexico (Dall, 1918, as 0. veatchii). Recent: Lower California and the Gulf of California, Mexico. Jordan and Hertlein (1926) discuss this species and it? probable relationship with other forms. In spite of Ball's conclusion, 0. veatchii Gabb appears to be a synonym of Conrad's earlier described 0. vespertina. 0. amara Carpenter may be identical. This species is a fluted oyster with a moderately thick shell which is sculptured with six to fifteen, irregular, rather angular plications which increase in number from the beak outward. It is of medium size, averaging about 50 to 75 mm. in length. It is distinguished 1 Jour, de Conchyl.. Vol. 57, p. 220, 1909. 2 Hist. Anim. s. Vert., Vol. 6, p. 206, 1819; Delessert, Rec. Coq. Lamarck, pi. 17, figs, la-d, 1841; Sowerby, in Reeve's Conch. Icon., Vol. 18, Ostrea, pi. 8, fig. 13, 1871. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 153 from 0. lurida Carpenter by its larger, thicker, more plicate shell; from 0. heermanni Conrad by its smaller thinner shell; and from 0. ahvoodi Gabb by having both valves plicate instead of only one. It is similar and perhaps closely related to several Atlantic coast species, such as 0. haiiensis Sowerby, 0. sculpturala Conrad, 0. subfalcata Conrad, etc. Ostrea vespertina Conrad variety sequens AriKild Oslrea I'espeiima Conrad, var. sequens Arnold, U. S. Geol. Surv., Bull. 396, p. 79, pi. 29, figs. 5, 6, January 15, 1910; Arnold and R. Anderson, Bull. 398, pi. 51, same figures, 1910; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 419, 1915, listed questionably; Nomland, Vol. 10, p. 219, 1917. "This species is smaller, thinner, more circular in outline, and decidedly less plaited than the typical O. vesper- tina. The right valve of O. i-esperiiiia var. sequens is less ornate than the same valve in O. resperiina." (Arnold). Type specimen: U. S. National Museum, No. 165,545, a left valve. Type locality: Northeast border of Kettleman Hills, Coalinga district; upper Pliocene. Miocene: Lower San Pablo formation of middle California, listed questionably (Clark). Pliocene: At the type localitj' and at several other localities in the upper part of the Etchegoin formation, just below the fresh-water Tulare Lake beds (Arnold: Nomland); very abundant in the last phases of marine deposition in the middle Pliocene of localities 256, 258, 262, etc., S. D. S. N. H., Santa Clara Valley. Los Angeles County (H. R. G.). Arnold pointed out that this variety lived during the period of unstable conditions during the change from the inland sea of Etchegoin time to the fresh-water lake of Tulare time. The present authors are not acquainted with the characters that distinguish this form from Ostrea lurida Carpenter. Ostrea atwoodi Gal^b Ostrea alwoocHi Gabb, Geol. Surv. Calif., Palseo., Vol. 2, section 1, pp. 33, 34, pi. 10, figs. 58, 58o, pi. 11, fig. 586, 1866; Arnold, U. S. Geol. Surv., Bull. 396, p. 140, pi, 17, figs. 1, 2, 1910; Arnold and Robert Anderson, Bull. 398, pi. 39, same figures, 1910; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 2,53, 1916; Nomland, Vol. 10, p. 219, 1917. "Shell broad, irregular, thin; partly attached, sometimes by nearly the whole of the lower surface; free surface of lower valve marked by numerous irregular radiating ribs crossed by lines of growth; upper valves more squamose and not radiated (in the only specimen I have seen). Hinge broad at the base, triangular, not deep and sometimes slightly oljlique ; inner margin of the shell not denticu- lated. Muscular scar broad." (Gabb, original description.) Gabli's type appears to have been 55 or 60 mm. long and the same in width. Miocene: "On San Lorenzo Creek, Monterey County; either Miocene or Pliocene" (Gabb); San Pablo forma- tion of middle California, upper Miocene (Nomland). Pliocene: Upper Jacalitos and lower Etchegoin of the Coalinga district (Arnold); common in the Chione elsmerensis, Turrilella nora and Pecten coalingoisis zones, lower and middle Pliocene, Coalinga region (Nomland); Etechcgoin of Sargent oil field (Martin). Ostrea tayloriana Gabb Ostrea tayloriana Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, sect. 1, pt. 1, p. 34, pi. 12, figs. 60, 60a, 1866, sect. 1, pt. 3, p. 106, 1868-9; probably not of Dall, Seventeenth Ann. Rept. U. S. Geol. Surv., Pt. 1, p. 844, 1896; nor of Dall, Washington Academy of Sciences, Alaska, Res. Harriman .Vlaska Exped., Vol. 4, p. 113, 1904; reissued by the Smithsonian Institution, 1910; not of Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 428, pi. 33, fig. 3, 1926, = O. erici. Type specimen: In the collection of the University of California. Type locality: "From the Miocene; from San Marcos Pass, near Santa Barbara" (Gabb) ; now believed to be upper Eocene. 154 San Diego Society of Natural History [ Memoirs Enccnc: At the type locality, probably upper Eocene.^ ? Miocene: Atka Island, Pavlof Bay, Unga Island, and Kadiak Island (Dall, 1896); "Miocene Unga Island and near Pavlof Volcano on the Peninsula of Alaska" (Dall, 1904). Dall united this form with unrelated species. It seems to have been confused with 0. idriaensis Gabb. Dall's reports from the Alaskan Miocene are probably erroneous; and the specimens reported from the middle Pliocene of Lower California by Jordan and Hertlein have since been renamed erici. Ostrea erici Hertlein "Oslrea tayloriaria Gabb," Jordan and Hertlein, Proc. Calif. .\cad. Sci., Ser. 4, Vol. 15, p. 428, pi. 33, fig. 3, 1926. Ostrea erici Hertlein, Journ. Paleo., Vol. 3, p. 295, Sept., 1929. Type specivien: In the collection of the California Academy of Sciences. Type locality: Mouth of large arroyo northwest of Elephant Mesa, Scammon Lagoon Quadrangle, Lower California, Mexico. Pliocene: Cedros Island, and northwest of Elephant Mesa, west coast of Lower California, Me.xico (Jordan and Hertlein). This species should be compared with 0. chilensis Philippi and 0. panzana Conrad. Superfamily Pectinacea Shell usually somewhat inequivalve, more or less circular, hinge line straight or nearly straight, often with wing-like extensions called ears; young shells with two muscle scars (dimy- arian), adults usually with onlj' one (monomyarian) ; shell .structure semi-pearly, usually with some traces of a prismatic laj'er. Family PECTINIDAE Shell witli the ears well developed; internal ligament inserted in a cardinal pit or series of rachat- ing grooves under the beaks, sometimes in the adherent species externally prolonged in a notch be- tween the beaks; very young shells dimyarian, with small taxodont teeth and a prismatic shell layer, indicating relationship with the Pteriidce and the XucuUdw, the teeth usually entirely obsolete in the adults, and the prismatic layer seldom showing, the adults monomyarian, with the ears dorsal and ventral instead of anterior and posterior. Genus PECTEN Osbeck, 1765 Feclen Klein, 1753, pre-Linnjean. Peclen Osbeck, "Dagbok ofver en Ostindisk Resa aren 1750-52, ....," p. 299, Stockholm, 1757, pre-Linnsean ; Ed. 2, revised by Osbeck and translated into German by J. G. Georgi, "Reise nach Ostindien und China ....," p. 391, Rostock, 1765; Ed. 3, translated into English from the German by J. R. Forster, "A Voyage to China and the East Indies ," Vol. 2, p. 100, London, 1771; Sherborn, Index Animalium, Section 2, Peclen, 1929. Peclen Miiller, Zoologite Danicse Prodromus, pp. 31, 248, Havnise, 1776, species cited include among others Peclen. maximiiii, = Ostrea iiin.rinia Linnaeus, and Pccten islandicus Miiller. Peclen, of varioiis other early authors, in part: Da Costa, Brit. Conch., p. 140, 1778; Chemnitz, Neiies Syst. Conch. Cab., Vol. 7, pp. 261-356, pis. 60-68, 1784; etc. Hiiiiiites Defrance, Diet. Sci. Nat., Vol. 21, p. 169, 1821, species in the original list H. corlesyi Defrance and H. dubuis- sorri Defrance; Deshayes in Lamarck, Hist. Nat. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 7, p. 148, 1836; Herrmannsen, Ind. Gen. Malac, Vol. 1, p. 533, 1846-7, type not cited; Gray, Proc. Malac. Soc. London, p. 201, 1847, type cited H. eorleysii; Dall, Trans. Wagner Free In.st. Sci., Phila., Vol. 3, pp. 689, 699, 711, 1898. Hiiniitn Fcrussac and Deshayes, Tableaux .Systematic|ue des ,\nimaux Molhisque etc., Tabl. Syst. Cieneraux, p. xl, 1822; Gray, Ann. Phil., X. S., Vol. 12, p. If3, August, 1826; Menke, 1828 (fide Herrmannsen). Uitniiis Gray, Ann. Phil., N. S., Vol. 12, p. 362, Nov., 1826; Sowerby, Syst. Index Min. Conch. Gt. Brit., p. 244, 1835; Wood, Ann. and Mag. Nat. Hist., Ser. 1, Vol. 6, p. 253, 1841, another emendation of Hinnites. ' Woodring (Trans. San Diego Soc. Nat. Hist., Vol. 6. p. 159. 1930) reports O. laylitriaria in the Tiirritella tarinta zone, upper Eooene, of the Santa Ynez Mountains, near Gaviota Pass, Santa Barbara County. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 155 Type (by monotypy), Pecten adscensionis Osbeck, Recent, Cross Bay, Ascension Island, south Atlantic, in 24 fathoms. Shell nearly always somewhat mequivalve, but, with the exception of the ears, usually approxi- mately equilateral, suborbicular; hinge line straight, the ears well developed, the ventral one of the right valve more or less separated from the main body of the shell by a byssal notch; sculpture normally of external radiating ribs or striae; resilium triangular, situated in a pit in the middle of the inside of the hinge, in heavy-shelled or short-hinged species sometimes well-developed grooves and ridges diverging from the apex of the resilial pit; the single adductor muscle large, rounded, dorsal, being the strongly developed posterior adductor of the young stages. Geologic range: Carboniferous to Recent (Jackson). Distribution: World wide. The Pectens or scallop shells constitute a single distinct and very important group. Their phylogeny along with that of related groups has been very carefully worked out by R. T. Jackson in his classic work on the "Phylogeny of the Pelecypoda."' In 1897 A. E. Verrill wrote a discussion of the characters of the genus, dividing it up into many genera, subgenera, and sections on the basis of very minor characteristics, and proposing many new names-. The next year Dall prepared a summary of the subgenera and sec- tions of the genus and reviewed many of our Pacific coast species'. Soon afterward Ralph Arnold compiled a monograph of the "Tertiary and Quaternary Pectens of California" which has been the foundation of all subsequent work on west American Pectens*. Studies of variations carried on in the East and in Europe by C. B. Davenport and others have been of considerable importance in showing the extent of variation possible within a single species.^ Fossil as well as living species show very wide variations. The study of these varia- tions is indispensable for an understanding of the range and distribution of species and should be pursued by anyone who is considering the naming of new species or varieties. Because of the failure to recognize the variabilitj' of Pectens, our common species are encumbered with long lists of synonyms and varieties of doubtful value. The variable characters are: convexity of valves; thickness of shell; size; shape, number, and spacing of ribs; relative length of hinge line; size of the apical angle; amount of obliquity of the valves; ratio of altitude to width; etc. The characters mentioned first are the most variable: the convexity may be twice as much in one individual as in another; the thick- ness and size vary with age, with the temperature, depth, and salinity of the water; the ribs may vary froin low and rounded to high and square, and some specimens may have half again as many as others; the relative length of the hinge line depends on whether deposition has taken place last on the ears or on the free margins of the valves; the apical angle varies somewhat in absolute size and on very convex individuals appears larger because the beak is tilted downward ; some individuals are considerably more drawn out ' Jackson, Robert Tracy: "Phylogeny of the Pelecypoda, the Aviculidae and their Allies," Mem. Bost. Soc. Xat. Hist., Vol. 4, pp. 277-400. 1890. 2 Verrill. A. E.: "A Study of the Family PectinidEe, with a Revision of the Genera and Subgenera." Trans. Conn. Acad. Sci., Vol. 10. pp. 41-96, 1897. 3 Dall. William Healey. in the "Tertiary Fauna of Florida." Trans. Wagner Free Inst. Sci., Phila.. Vol. 3. pp. 689-758, 1898. * Arnold. Ralph: "Tertiary and Quaternary Pectens of California," Prof. Paper 47 U. S. Geol. Survey, pp. 1-264. pis. 1-53. 1906. ^ Davenport. C. B.: "On the Variation of the Shell of Pecten Irradians Lamarck from Long Island," .^mer. Naturalist, Vol. 34. pp. 863- 877, 1900. : "A Comparison of some Pectens from the East and West Coasts of the United States." Mark Anniversary Volume. pp. 12.3-136, 1903 (Henry Holt & Co.. New York). : "Quantitative Studies in the Evolution of Pecten. III. Comparison of Pecten Opercularis from Three Localities of the British Isles," Proc. Amer. Acad. .\rts and Sci.. Vol. 39, pp. 124-1.59. 1903. and Hubbard. M. E.: "Studies in the Evolution of Pecten. IV. Ray Development in Pecten Varius." Journ. Exp. Zool.. Vol. 1. pp. 607-616, 1904. ; "Evolution without Mutation." Journ. Exp. Zool.. Vol. 2, pp. 137-43. 1905. 156 San Diego Society of Natural History [Memoirs dorsally than others, giving the shell an oblique appearance ; and the ratio of the altitude to the width is also variable. Some characters vary together: the width of the smooth lateral areas outside of the last ribs is greatly influenced by the convexity of the individual, as is also the curvature of the ears; individuals with heavier shells are apt to have stronger, sharper ribs, except that gerontic types often greatly increase the thickness of the shell and at the same time lose the definiteness of their sculpture. In the following classifica- tion the forms that have received distinct names but are not known to have any strati- graphic significance and are found to have many combinations of intergrading characters (as a complicated aggregate of related variations should be expected to have) are grouped under a single specific name, thus stressing their relationship, but are distinguished as varieties lest they be found at any time to be of value. If they all were to be considered distinct, we should eventually, to be consistent, have a separate name for every form that lived in every little bay and along every stretch of shore where the living conditions were slightly different, and geologic correlations (the chief object of paleontologic study) would be very difficult. Jackson has pointed out that in monomyarians like the Pectens and oysters the ani- mal has assumed a position within the shell at right angles to that occupied by dimyarian pelecypods. As a result the ears become ventral and dorsal instead of anterior and pos- terior respectively, and the hinge line is anterior while the free ends of the valves are posterior. Since to call them so is biologically correct and helps to convey a clearer pic- ture of the nature of the organism, it seems wise to follow Jackson's lead. The byssus is always ventral. The right valve is the valve with the byssus on the right (and bears the byssal notch), the left is the valve with the byssus on the left. The rest of the descriptive terms used here are as given in the introduction to Arnold's monograph. There has been a tendency among recent writers to separate the genus Pecten as here treated into several, sometimes many, distinct genera, restricting the name Pecten to a very limited part of the group. There are good reasons for subdividing the genus, for it must be admitted that the extreme forms are sometimes very dissimilar, that it is a long jump from Lyropeden, for instance, to Pscudanmssiuvi. Nevertheless, our generic lines are drawn principally for convenience at the points where groups are most easily separated, and it is difficult to see what useful purpose it would serve to break up and scatter to the winds this well-known and long-recognized genus. Geologists and others who know only a little of conchology can now recognize and talk with confidence about Pectens ; but if instead of one well-marked genus, they were confronted with many names recognizable generically only by specialists who have well-preserved material, matieral good enough usually so that the species could be recognized as easily as the genus, the nomenclature would no longer be useful to them. The Pectens are such an important group that it is well to handle them conservatively. Furthermore, the present lack of informa- tion about the exact nature of the type species and the consequent uncertainty in the nomenclature of some of the subgenera (which would be genera if the group were broken up) make it unwise for the time being to upset the long-established custom of assigning all the Pectens to a single genus. If later the present arrangement of the subgeneric nomenclature becomes stabilized, most of the species commonly known as Pecten can be left under that name, and it may be found useful to recognize as additional genera Janira, Amusium, Propeamussium, and Pseudamussium. Such a subdivision of the Pecten group would do much less harm than the subdivision according to the arrangement of subgenera that has generally been in use up to this time, for Pecten, s. s.. Pallium, Lyropeden, Vertipeden, Patinopecten, and Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 157 Aequipeden would still remain as subgenera, and only the forms with more strikingly different appearances would be separated. As Janira and Amusmni, despite their dis- similar appearances, are really very closely related, it is possible that Janira should be classified as a subgenus of Amusium. For the last fifty or seventy-five years many writers have been considering the group of species with the left valve flat, or nearly flat, or concave, typified by Ostrea maxima Linnaeus, as the typical subgenus of Pecten. However, most of the early writers, who used the term Pecten in a broad sense, included under it a large number of species that belong to the group with both valves inflated. As the latter group is the more important, with a greater variety of forms and many more species, it was natural to think of it as the nor- mal group, and of Pecten maximus and its relatives as specialized derivatives, which they are. Jackson in 1890, and, even later, others who have been more interested in mor- phology and phylogeny than in nomenclature have assumed that the larger group should bear the name. At least two other generic names have been proposed to include Pecten maximus because it differed from what was thought to be a normal Pecten, and these names have at times had considerable use. Thus it is not surprising that Osbeck, who was familiar with the pre-Linnsean usage of the well-known term, should apply it to a species of the larger group. We may be glad that he did, for it enables us to retain Pecten for the larger part of the shells that have been so called throughout most of conchological history, even though the genus as here used be divided up. The only unfortunate feature of Osbeck's usage of the name Pecten lies in the brevity of his description and the remoteness of the type locality of his type species, which make it difficult to discover on short notice the exact characters of the species. The information given by Osbeck is, however, quite sufficient to indicate the subdivision of the genus to which his species belongs and to enable later workers to identify it and ascertain its char- acters more precisely. Osbeck writes (Vol. 2, p. 77 of the English edition) : "We steered from W. by N. to get the longitude of Ascension Island, near which we sailed in the forenoon; and at last cast anchor in the Cross-bay on the same island, with twenty-four fathoms ground." After describing the plants and animals that he found while the ship remained a few days in Cross Bay, he writes (p. 100) : "After we had got all our men on board again, and 41 tortoises on the deck, we weighed anchor. With the cable we pulled up a piece of coral, on which a red shell (Pecten Adsce7isio7iis) was growing, which on its valves represented many branches. We took it with us, and at present it is preserved in one of the greatest cabinets of natural curiosities in Sweden." As Pecten had long been in use for scallop shells, even in Osbeck's time, it is evident that Osbeck had a species of scallop or a scallop-like form that had been growing to a piece of coral and on which there were many ribs, multiplying by division. The many ribs and the sessile habit indicate that it was a form related to Chlamys but belonging to the section that was formerly called Hinnites. The red color may be of help in identifying the species or variety. It may be a reddish variety of P. 7nultistriatus (Poll) or of P. distortus Da Costa -|- sinuosus (Gmelin), or it may be Hinnites corallinus Sowerby, or an entirely distinct island species. In any case the definite type locality and meager fauna of Ascension Island make the ultimate precise identification of the species practically certain, if indeed the type specimen cannot be located "in one of the greatest cabinets of natural curiosities in Sweden." Since Osbeck is the first writer to use Pecten binomially, it is here proposed to follow his usage as nearly as it can now be ascertained. 158 San Diego Society of Natural History [Memoirs There is no question about the nomenclatorial availabihty of Osbeck's names. The German edition is not merely a reproduction or translation of a pre-Linnsean work, for it had been carefully revised by its author, as is shown by the following quotation from Mr. Forster's preface to the English edition: "A word or two I must say in regard to the translation, which is made from the German, and not from the original Sivedish; but as Mr. Osbeck not only revised the German translation, but also made some additions to it which are not found in the original Suwdish edition, it is rather an advantage to the work than a prejudice." (English edition. Vol. l,p. X.) Furthermore, Osbeck is strictly binomial in all three editions. He describes many plants, birds, fishes, and other animals, often going into considerable detail, and in the case of the plants sometimes adds illustrations. It is unfortunate that he was not equally interested in invertebrate animals, or we might have had a fuller description of Pecten adscensionis. However, we must agree with Sherborn that Osbeck's Pecten is nomenclatorially available and must be dealt with. Osbeck was a pupil of Linnaeus, and after his work was published Linnaeus wrote him a letter, complimenting him especially on his nomenclature: "You, Sir, have every where travelled with the light of science: you have named every thing so precisely, that it may be comprehended by the learned world ; and have dis- covered and settled both the genera and species. For this reason, I seem myself to have travelled with you, and to have examined every object you saw with my own eyes." (English edition, Vol. 2, pp. 127-128.) Subgenus PECTEN, s. s. Shell with valves moderately and nearly equally inflated, ribs small and numerous, often gath- ered into many small Inmdles or fascicles, spinose or covered with microscopic lattice-like sculpture; hinge line short, ventral, ears large and extended, hyssal notch dcej) and broad, ctenolium (pectinidial teeth) strong, dorsal ears small, oblique. Geologic range: Triassic to Recent. Distribution: World wide. This subgenus appears to represent the main stock from which all the other modern subgenera have been derived. It is possible, however, that, as at present restricted, the early Mesozoic forms could not be included, or that the other subgenera instead of being derived directly from this one may have evolved along with it from a small thin-shelled group like Entolium Meek (Carboniferous to Cretaceous) or from Pseudamussium. The many fine radial ribs distinguish the typical subgenus, as well as the form of the ears. Section Pecten, s. s. Shell up to advanced youth like that of the section Chlamys, later becoming sessile and irregular, in which stage the resilial pit is elongated and the whole shell is thickened, becoming oyster-like. These sessile forms, phylogenetic derivatives of the section Chlamys, have often been treated as belonging to a distinct genus, being placed sometimes even in a different family ; but the reason for this treatment is that the two look very differently, not that thej^ are genetically separated. The single Pacific coast species appears to have specific relation- ships with Pecten hastatus, being descended perhaps from the same Eocene ancestor, from some form like P. proaims Arnold. The lower Miocene specimens have a short sessile stage and are difficult to separate from species of Chlamys; and the young of the living VoltjmeI] Pliocene and Pleistocene Mollxjsca of California 159 form has too many characters in common with hastatus to allow the hypothesis to sound plausible that all the specific resemblances are coincidences. It seems highly probable and in accord with the natural facts that each of the species of sessile Pectens, which have ap- peared from time to time in geologic formations dating from the Triassic to the Recent, has individually separated from the main Pecten stock and hence has no particular rela- tionship with the others. If this be so, the sessile habit is merely of specific, hardly even of sectional, importance; and to be entirely consistent we should not separate Chlamys from Pecten, s. s., at all. For the sake of convenience, however, the name Chlainys is here em- ployed in a sectional or pseudosectional sense. According to Blainville's figures' the species cortesyi, described as a fossil from Plaisantin, Italy, is very similar to multirugosus, and this fact would be surprising if it were not for the increasing accumulation of evidence to show that migration of mollusks between CaUfornia and Europe in the Miocene was possible and that a number of species in the two regions are either the same or very closely related. On the other hand, the ma- jor part of the growth of a sessile form of Pecten is so irregular and is so much determined by the environment that the specific relationships can only be seen by examining the young Chlamys stage. If an examination of the young of cortesyi should show that it is descended from a different species of Chlamys, it would be desirable to have a different sectional name either for the Pacific coast or for the Italian species, or both; and Hinnita Gray 1826 with the type Lima gigantea, as noted by Gray in 1847, would be ap- propriate for the Pacific species, were it not for the earlier usage of Hinnita by Ferussac and Deshayes, probably for the Italian species, before the Pacific species was known. In this connection, the discussion by Bucquoy, Dautzenberg, and Dollfus- of the re- lationship between Pecten multistriatus (Poll) and P. distortus Da Costa + sinuosus (Gmelin) is very interesting. The authors give good figures of the two forms and ex- plain that they may be only varieties of the same species, being indistinguishable until the form distortus attaches itself and becomes a sessile or typical Pecten. They think that the question of whether or not a given individual will attach itself may be determined by the environment. Perhaps distortus is a normal Chlamys just changing over into a typical Pecten. Pecten (Pecten) multirugosus Gale Plate 11, Figures 5a, 56 Lima gigantea Gray, Ann. Phil., New Series, Vol. 9, p. 1.39, 1S25, not Plagiostoma ( = Lima) gigantea Sowerby, Min. Conch. Gt. Brit., Vol. 1, p. 176, pi. 77, 1812; Wood, Catalogue Suppl., pi. 2, fig. 7, inedited, 1825 or 26 {fide Gray). Hinnita gigantea Gray, Ann. Phil., New Series, Vol. 12, p. 10.3, 1826. Not Pecten giganteus Munster in Goldfuss, Petrifacta Germanise, Ed. 1, Vol. 2, pt. 4, p. 48, pi. 90, fig. 14, 1834; Ed. 2, p. 46, pi. 90, fig. 14, 1862. Hinnites giganteus Gray, Sowerby, Zool. Journ., Vol. 3, p. 70, 1827; Thes. Conch., Vol. 1, Hinnites, p. 80, pi. 20, figs. 5-7, 1843; Reeve, Conch. Icon., Vol. 8, Hinnites, pi. 1, fig. 3, 1853; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 164, 193, 233, 290, 312, 350, 351, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, pp. 522, 527, 528, .534, 536, 539, .540, 645, 665, 683, 1864; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 105, 1868-9; Whiteaves, Trans. Roy. Soc. Canada, Vol. 4, sec. 4, p. 119, 1887; Cooper, Seventh Ann. Rept. Calif. St. Mineralogist, p. 243, 1888 (Santa Rosa Island occurrence excepted, fide Arnold); Keep, West Coast Shells, p. 165, fig. 138, 1888, 1892; Weymouth, Calif. Fish and Game Comm., Fish, Bull. No. 4, p. 25, pi. 1, fig. 3, pi. 2, figs. 1, 2, 1920; Dall, Bull. 112 U. S. Nat. Mus., p. 20, 1921; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. .563, 1922; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 21, pi. 30, figs, la, 16, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 63, pi. 25, figs, la, 16, 1924 (but not from the "Pliocene of Santa Rosa Island," fide Arnold); Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. * Blainville, Man. Malac p. 524, Atlas pi. 61, fig. 1, 1825. Hinnites cortesyi Defrance is the type of Hinnites Defrance, which now falls as a synonym of Pecten, a.s. ' B., D., and D., Lea MoUusqucs Marins du Roussillon. Vol. 2, pp. 104-109, 1889. 160 San Diego Society or Natural History [ Memoirs Hinnila pouhoni Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, p. 182, pi. 14, October, 1834, not Peclen ■poulsoni Morton, Synopsis of the Organic Remains of the Cretaceous Group of the United States, p. 59, pi. 19, fig. 2, Philadelphia, published early in 1834 (the preface dated January 1), — a common Claiborne species. f Peclen conmhts Valenciennes, Voyage of the Venus, pi. 18, fig. 2, Paris, 1846, not Pecten comalus Miinster in Goldfuss, Petrifacta Germania;, Ed. 1, Vol. 2, pt. 4, p. 50, pi. 91, fig. 5, 1834; Ed. 2, p. 47, pi. 91, fig. 5, 1862; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 528, 1864. Pecten (Hinnites) giganteus Gray, Kiister and Kobelt, Conch. Cab., Vol. 17, Pt. 2, sp. 228, pi. 65, figs. 9, 10, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 115, 1903; Keep, West Amer. Shells, p. 42, fig. 22, 1904; Arnold, Prof. Paper 47, U. S. Geol. Survey, p. 93, in part, pi. 29, figs. 2, 2a, not fig. 1, 1906; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 45, 1916; Nomland, pp. 212, 219, 1917; Kew, BuU. 753 U. S. Geol. Survey, p. 78, 1924. Not "Pecten (Hinnites) giganteus Gray", Eldridge and Arnold, Bull. 309, U. S. Geo!. Survey, p. 17, pi. 32, fig. 1, 1907 (= Spondylus perrini Wiedey, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 138, pi. 17, figs. 6, 7, 1928). Pecten (Chlamys) muUirugosus Gale, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 92, 1928. Shell of young a Chlamys, having numerous small, somewhat spmose ribs, those of the right valve low and irregular but arranged roughly in 20 to 22 paired fascicles, those of the left valve with every fourth or fifth to the number of 10 or 11 accentuated above the others and bearing more prominent spines; ears like those of P. hastahts at a similar age; adult shell attached by the right valve, which usually loses almost immediately all its character, left valve continuing more or less irregularly with the same sculpture, having the 10 or 11 prominent rows of spines, and soon developing as intercalaries 10 or 11 more, almost as prominent, with sometimes a tertiary set; hmge rough and irregular, the cartilage pit becoming greatly elongated in a direction transverse to the hinge line. Dimensions (rough average of Uving specimens): Altitude 105 mm.; length 95 mm.; length of hinge 55 mm.; diameter of two valves 40 mm. Type specimen: No. 5 in the type collection of the San Diego Society of Natural History. Type locality: San Diego; Recent. Pliocene: Carrizo Creek district, Imperial Co., Calif. (Arnold); Pacific Beach, San Diego (Arnold); Ventura and Los Angeles counties (Cooper, Kew); middle Pico, middle Pliocene of loc. 228 S. D. S. N. H. southeast of Pico Canyon, one medium-sized left valve (H. R. G.); Fourth and Broadway, Los Angeles (Moody); upper Pico, upper Pliocene of loc. 225 S. D. S. N. H. between Timber Canyon and Santa Paula Creek, Ventura Co., one large left valve (H. R. G.); ? "Pleistocene" of Santa Barbara (Cooper). Pleistocene: Tomales Bay, Marin County (Dickerson); Santa Barbara to San Diego (Cooper); upper and lower San Pedro series of San Pedro, Los Angeles Co. (Arnold); "Saugus," of Ventura Co. (Water- faU). Living: Aleutian Islands, Alaska, to Magdalena Bay, Lower California (Dall). Variety multirugosus, s. s. Shell when young more nearly circular in shape than that of P. hastatus, beginning to become irregular at an early stage, when still only 15 to 25 mm. in altitude. Pecten (Pecten) multirugosus variety crassiplicatus Gale Hinnites arassa Conrad, U. S. Pacific Railroad Survey, Reports, Vol. 7, Pt. 2, p. 190, pi. 2, figs. 1, 2, 1857, description reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 181, 1909; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 595, 1864; not Pecten crassiis A. Risso, Histoire Naturelle des Principales Productions de I'Europe M6ridionale, Vol. 4, p. 300, Nov., 1826. [Pecten] Hinnites crass^^s Conrad, DaU, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 711, 1898. "Pecten (Hinnites) giganteus Gray," Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 93, in part, pi. 29, fig. 1 only, a figure of Conrad's type, 1906; Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 300, 304, in part, 1917. "Hinnites giganteus Gray," Arnold, Bull. 396, U. S. Geol. Survey, p. 21, pi. 10, fig. 2, Jan. 15, 1910; Arnold and Ander- son, Bull. 398, p. 94, pi. 32, fig. 2 (same figure), 1910. Pecten (Chlamys) mvltirvgosvs variety crassiplicatus Gale, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 93, 1928, new name for crassus Conrad. Shell hke that of the typical variety but usually with the Chlamys stage lasting longer, lasting imtil the shell is 25 or even sometimes 45 mm. in altitude, the young shell relatively higher than long. Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 161 practically the same shape as P. hastatus, the free valve of the adult usually having fewer and coarser plications. Dimensions: Much like those of the typical variety, very variable. Type specimen: No. 13,336 in the U. S. National Museum. Type locality: Santa Margarita formation, of the Salinas Valley, middle California. Middle Miocene: (Arnold, 1910). Upper Miocene: Santa Margarita formation, type locality (Conrad) ; north of Coalinga, Fresno Co. (Arnold; Noniland). Dall and others have thought that it might be possible to separate the upper Miocene form described as crassa from the common Pliocene to Recent species formerly known as Pecten giganteus (Gray), but the distinction is still of doubtful significance. This older form of attached Pecten resembles even more closely than the living form P. hastatus and its upper INIiocene relatives here grouped under P. bartschi. It is more than likely that the paratypes of P. Jiodgei Hertlein are the young of crassiplicatus, though it is difficult to be sure where the type belongs. Intergradations between crassiplicatus and bartschi, and between bartschi and hastatus in the upper Miocene make the distinctions very difficult, although of course, as soon as the shell shows evidence of attachment it should be assigned to crassiplicatus. Some of the other forms cited questionably in the synonymy of P. bartschi maj' be young Hinnites also, and it is possible that one of these names should be used instead of crassiplicatus. There is almost enough material already collected to work out genetic series from the Eocene proavus Arnold through bartschi to hastatus and from proavus, perhaps also through bartschi, to crassiplicatus and multirugosus. Section Chlamts Bolten, 1798 Chlamys Bolten, Mus. Boltenianum, p. 161, 1798, species cited include, among many others, (1) C. cinnabarina, under TV'hich references are given to Oslrea islandica Gmelin, sp. 55, Chemnitz, Vol. 7, pi. 65, figs. 615, 616, and (2) C. islandica, mider which no references are given; Herrmannsen, Ind. Gen. Malac, Vol. 1, p. 231, 1846-47, type designated, Pecten islandicus Linnseus, referring almost certainly to Gmelin's edition of Linnseus, which was included in the Boltenian references; Meek, U. S. Geol. Surv. of the Territories, Vol. 9, p. 23, 1876, accepts Herrmannsen's designation of iype. Type (by subsequent designation, Herrmannsen, 1846-47), Pecten islandicus (Lin- naeus) = Ostrea islandica Gmelin in Linnseus, Syst. Nat., Ed., 13, p. 3326, 1791 = Pecten islandicus Miiller, Prodr. Zool. Dan., p. 248, 1776; Recent, circumboreal. Ribs small and numerous, spmose, or rounded and covered with cross-hatching; shell never becoming sessile or irregular. According to the dictionary and to Bolten's usage, the word Chlamys is feminine. Pecten (Pecten) islandicus Miiller Plate 11, Figures la, 16 Pecten islandicus Muller, Zool. Dan. Prodr., No. 2990, p. 248, 1776; Chemnitz, Neues Syst. Conch. Cab., Vol. 7, p. 304, pi. 65, figs. 615, 616, 1784; Lamarck, Hist. Nat. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 7, p. 145, 1836; Sowerby, Thes. Conch., Vol. 1, p. 75, pi. 17, figs. 159, 160, 161, 1842; Middendorff, "Beitrage zu einer Malacozoologia Rossica," Vol. 3, M6m. Acad. Imp. Sci. , St.-P^tersbourg, Ser. 6, Vol. 6, Pt. 3, p. 12 (dr.), 1849; Wood, Mon. PaliBO. Soc, Vol. 4, "Mon. Crag Moll.", Vol. 2, p. 40, pi. 5, fig. 1, 1851; Kuster and Kobelt, in Martini-Chemnitz, Syst. Conch. Cab., Second Series, Vol. 17, Pt. 2, Spondylus und Pecten, No. 24, p. 59, pi. 16, figs. 1, 2, p. 105, pi. 30, figs. 1-6, 1888; Brogger, Norges Geol. Undersbgelse, No. 31, p. 228, fig. 23, pi. 5, figs, la-d, 1901; Dall in Moffit, Bull. 533 U. S. Geol. Survey, pp. 45, 46, 47, 1913. Ostrea cinnabarina Born, Testacea Musei Csesarei Vindobonensis, p. 103, 1780 (fide Deshayes in Lamarck, 1836); Dillwyn, Cat. Rec. Shells, Vol. 1, p. 256, 1817. 162 San Diego Society of Natural History [Memoirs Ostrea islandica Miiller, Fabiieius, Fauna Gronlandica, p. -415, 1780; Gmelin in Linnseus, Syst. Nat., Ed. 13, p. 3326' 1791. Pecten rubidus Martyn, Univ. Conch., Vol. 2, pi. 153, fig. 1, 1784; not "Pecten rubidus Martyn" of Hinds and Midden- dorff {fide Dall, Nautilus, Vol. 27, p. 122, 1914). Ostrea demissa Solandcr, Mus. Calonnianum, p. 52, 1797. Chlamys cinnaharina , Bolten, Mus. Boltenianum, p. 161, 1798. Chlamys islandica Bolten, loc. cil. Peclen pealii Conrad, Amer. Marine Conch., Vol. 1, p. 12, pi. 2, fig. 2, 1831. Pecten fabricii Philippi, Abbildungen und Beschreibungen neuer oder wenig gekannter Conchylien, Vol. 1, p. 101, Pecten, pi. 1, fig. 5, January, 1844. Not "Pecten islandicvs MuUer," Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 257, 1888 (fide Arnold, = variety jordani Arnold). Chlamys islandica Chemnitz, Verrill, Trans. Conn. Acad. Sci., Vol. 10, p. 72, pi. 16, figs. 2-5h, pi. 20, fig. 9, pi. 21, fig. 2, 1897. Pecten (Chlamys) islandiciis Muller, Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, pp. 708, 735, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 113, pi. 45, figs. 1, lo, 1906; Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; Oldroyd, Univ. Wash. Publ. PugetSound Biol. Sta., Vol. 4, p. 18, pi. 24, figs. 1, 2, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 54, pi. 8, figs. 1, 2, 1924. Pecten (Chlamys) islandicus Muller n. var. ?, Waterfall, Univ. Calif. Publ. Geol., ^'ol. 18, pp. 78, 84, 1929. Shell large, of medium thickness, subcircular, equilateral except for the ears, somewhat higher than long, valves with very low convexity, anterior margins back of the ears (or sides as they are often called) only slightly incurving; sculpture of numerous rounded, somewhat flat-topped, narrow ribs, finely imlaricated when fresh, smooth w-hen worn, very variable in number, multipl>'ing with growth by bifurcation and intercalation, more by bifurcation on the right valve, more by inter- calation on the left valve, usually twenty-five to thirty-five primary ribs on each valve, more distant on the left, the interspaces finely cross-hatched; hinge line about half the length of the shell, variable, the ventral ears about twice as long as the dorsal, the byssal ear romided at the extremity, sculptured with five or six major radiating riblets and some intercalaries, the byssal scar taking up less than a third the width of the ear, notch only of moderate depth, other ears sculptured with seven or eight radiating riblets. Dimensions: Altitude 82 mm.; length 75 mm.; length of hinge line 37.5 mm.; convexity of the two valves 27 mm., the left a little more convex than the right. Type specimen: At Copenhagen (?). Type locality : Iceland. ? Oligocene-Miocene: As P. branneri and P. imshburnei of middle California and Oregon (Arnold). Pliocene: Raised beaches at Nome, Alaska (Dall, 1913); uppermost Pliocene of Ventura Co., California (Waterfall). Pleistocene: "Pliocene" of Deadman Island, San Pedro (Arnold); boulder clays of the northwest American coast, Alaska, British Columbia, also New England and New Brunswick (Dall); Clyde beds of England (Wood). Living: Arctic Ocean to Kamchatka and Puget Sound on the west, to Chesapeake Bay on the east (Dall); Scandinavia and north Scotland (Wood). This species is characterized by its large size when adult, by its large number of irregularly sized ribs, and by the reticulated interspaces. According to Arnold, there were in 1906 only two authentic specimens known from California, both of them coming from the "Pliocene" of Deadman Island. It seems probable, however, that the specimens de- scribed by Waterfall from the upper Pico, Santa Barbara zone, of Ventura County, should be assigned to the typical variety. From the descriptions and illustrations of Pecten branneri and P. washburnei Arnold, ^ there is practically nothing by which these forms can be distinguished from the typical variety of islandicus. The ears of branneri are not large for a fragment of a large specimen. However, it is possible that the narrower apical angle of branneri and the fewer, stronger ribs might be of significance and might serve to distinguish it. In any case, those forms are almost surely the ancestors of the 1 Peclen (.Chlamys) branneri Arnold. Prof. Paper 47 U. S. Geol. Survey, p. 55, pi. 3. figs. 9, 10, 11, ISOG. Pecten (Chlamys) washburnei Arnold, op. cit., p. 119, pi. 45, fig. 2, 1906. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 163 living islandicus, and are closely related to the Maryland Miocene P. marylandicus Wagner/ to say nothing of the Oligocene forms of the Northwest. Variety islandicus, s. s. Shell large, the altitude noticeably greater than the length; ribs numerous, narrow, rounded, slightly imbricated. Pecten (Pecten) islandicus Miiller variety hindsii Carpenter " Pecten fabricii Philippi" Gould (fide Carpenter, Brit. Assn. Adv. Sti., Rept. for 1863, p. 574, 1864). "Pecten rubidvn Martyn" Hinds, Zool. Voy. Sulphur, Moll., p. 61, pi. 17, fig. 5, 1844 (fide Carpenter, op. cU., p. 606). Pecten (? var.) hindsii Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 645, 1864, reprinted in Smithsonian Misc. Coll., No. 252, pp. 92, 131 (bottom pagination), 1872. Pecten {CMamys} liericeus var. hindsii Carpenter, Whiteaves, Trans. Roy. Soc. Canada, Vol. 4, sec. 4, p. 119, 1887; Dali, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 7C9, 1S98. Pecten (Chlainys) hericeus var. nararchvs Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 708, 1898; Wash. .\cad. Sci., Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 121, 1904, reissued by the Smithsonian Inst., 1910. Pecten (Chlamys) hnstotus var. hindsii Carpenter. ,\rnold. Prof. Paper 47 U. S. Geol. Survey, p. Ill, pi. 43, figs. 2, 2a, 1906. Pecten (Chlatnys) hnslatiis var. nararchiis Dall, .\rnold. Prof. Paper 47 U. S. Geol. Survey, p. 1 12. pi. 43, figs. 1, lo, lb, 1906. Pecten (Chlntnys) liiiidsii Carpenter, Dall, Bull. 112 V. S. Nat. Mus. p. 18, 1921; Oldroyd, I'niv. Wash. Publ. Paget Sound Biol. Sta., Vol. 4, p. 17, pi. 23, figs. 3, 4, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. .53, pi. 7, figs. 3, 4, 1924. PectcK [Chlamys) hindsii var. tiararchns Dall, Hull. 112 I'. S. Nat. Mus., p. 18, 1921: f)l(lroyd, I'niv. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 17, pi. 26, figs. 2, 3, 1924; Stanford Univ. Publ. Geol., \'ol. 1, p. 54, pi. 4, figs. 2, 3, 1924. Pecten (Chlamys) islandiois picoensis Waterfall, Vniv. Calif. Publ. Geol.. Vol. 18, pp. 78, 79, 83, pi. 5, figs. 2, 4, 1929. Pecten (Chlamys) it-ashburnei ventvrnnesis Waterfall, l^niv. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pecten (Chlamys) venturaens-is Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 84, pi. 6, fig. 4, 1929. Shell like that of the typical variety, but smaller, relatively longer; ribs somewhat more regular and fewer, usually not imbricated, covered with a minute lattice-like structure, those of the right valve multiplying principally by bifurcation, those of the left principally by intercalation. Dimensions: Altitude 60 mm.; length 60 mm.; length of hinge 29 mm.; convexity of the two valves, 19 mm. Type specimens: Of hiridsii and navarchus, both of which are based on "Pecten rubidus Martyn" Hinds, in the British Museum (fide Carpenter) ; of picoensis, No. 31,419, of venturaensis, No. 31,416, at the University of California. Type localities: Of hindsii and navarchus, Vancouver Island (fide Carpenter); of picoensis and venturaensis, upper Pico, Santa Barbara zone, uppermost Pliocene of Ventura Co., Calif. Middle Pliocene: Pacific Beach, San Diego (Hamlin in Arnold). Upper Pliocene: Type locality of picoensis and venturaensis. Pleistocene: "Pliocene" of Deadman Island, San Pedro Harbor, Los Angeles Co., Calif. (Arnold); Vancouver and Sucia Islands, Puget Sound (Newcombe); Alaska (Dall, 1904). Liring: Bering Sea to San Diego (Dall). This variety is very similar to typical islandicus, forming a link in the intergrading series between it and P. hastatus. Some specimens are slightly spinose on the left valve and show a tendency to bunch the ribs into fascicles as in P. hastatus, but the majority of the specimens have rounded ribs covered with a microscopic network as in Pecten beringianus. Other specimens show * Pecten marylandicus Wagner, Journ. Acad. Nat. Sci., Phila., Vol. 8, p. 51. pi. 2. fig. 2, 1839. Pecten tenuis Lea, Trans. Amer. Phil. Soc. Vol. 9. p. 246. pi. 35. fig. 33, 1845. Pecten {.Chlamys) marylandicus Wagner. Glenn, Mar>'land Geol. Survey, Miocene Volume, p. 376. pi. 99. fig. 6. 1904. 164 San Diego Society of Natural History [ Memoirs a thinning out of the ribs as in the form venturaensis, approaching so closely the varieties jordani and kincaidi that it is doubtful whether the former of these, at least, should be separated even varietally. Waterfall did not recognize the variability of this variety nor the fact that the ribs tend to multiply in different ways on the two valves, else he would not have added two more names to the synonymy. Pecten (Pecten) islandicus Miiller variety jordani Arnold Plate 11, Figure 4 Peden (Chlamys) jordani Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. Ill, pi. 12, figs. 6, 7, 1903; Prof. Paper 47 U. S. Geol. Survey, p. 114, pi. 44, figs. 1, la, 16, 1906; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pecten jordani Arnold, McLaughlin and Waring, Folio accompanying BuU. 69, Calif. St. Mining Bureau, pi. 1, fig. 49, 1914. Shell like that of the typical variety, with approximately the same shape, but smaller, the ribs less numerous and not multiplying so fast, those of the right valve much wider than the interspaces and not beginning to bifurcate until about 30 mm. long, those of the left romided, rather distant, the intercalaries appearing at about the same time as the bifurcations on the right valve, both valves with a secondary sculpture of microscopic network. Dimensions: Altitude, 37 mm.; length, 34 mm.; length of hinge line, 15 mm.; convexity of two valves, 11 mm. Type specimen: No. 162,522 in the U. S. National Museum. Type locality: "Pliocene" of Deadman Island, San Pedro Harbor, Los Angeles County. V. Pliocene: Santa Barbara (Arnold); upper Pico, Santa Barbara zone, Ventura Co. (Waterfall). Pleistocene: Type locality; also in the lower San Pedro series of the same locality (Arnold). Living: At various localities with hiridsii, not the specimen figured by Oldroyd (see kincaidi). This variety is intermediate between hindsii and kincaidi, and it is doubtful whether any of the distinctions are of significance. It has fewer, simpler ribs than the typical islandicus, and is small; it has fewer, broader ribs, and is less elongate parallel to the hinge than hindsii; the ribs of kincaidi are narrower and do not bifurcate. Pecten (Pecten)[islandicus Miiller variety kincaidi Oldroyd Pecten kincaidi Oldroyd, Nautilus, Vol. 33, p. 135, pi. 4, figs. 3, 4, 1920. Pecten (Chlamys) hindsii kincaidi Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 17, pi. 9, figs. 3, 4, 1924; Stanford Univ. Publ. Geol., Vol. 1. p. 63, pi. 12, figs. 1, 2, 1924. Pecten (Chlamys) jordani Arnold, Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 19, pi. 2, figs. 1, 2, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 55, pi. 28, figs. 5, 6, 1924. Shell like that of the variety hindsii but with fewer ribs, the ribs not multiplying, on the left valve faint intercalaries never rising to the height of the ribs. Dimensions: Altitude, 40 mm.; length, 38 mm.; length of hinge hne, 18 mm.; convexity of the two valves, 13 mm. Type specimen: In the Oldroyd Collection at Stanford University. Type locality: Puget Sound. Living: In Puget Sound (and elsewhere with hindsii ?). This variety is distinguished by its small size, and its few distant ribs- Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 165 Pecten (Pecten) opuntia Dall Plate 11, Figure 3 Pecten {Chlamys) ojmntia DaU, Trans. Wagner Free Inst. Sci., PhUa., Vol. 3, p. 707, pi. 29, fig. 6, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 113, 1903; Prof. Paper 47 U. S. Geol. Sun-ey, p. 118, pi. 41, fig. 2, 1906; Proc. TJ. S. Nat. Mus., Vol. 32, p. 527, 1907; Eldridge and Arnold, BuU. 309 U. S. Geol. Survey, p. 152, pi. 36, fig. 8, 1907; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 45, 1916; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 417, 1926; WaterfaU, Univ. Calif. Publ. Geol., Vol. 18, pp. 78, 79, 80, 81, 82, 1929. Shell of medium size, circular, not very convex, sides or anterior margins strongly incurving; sculpture of numerous (about 60) small, high, flat-topped ribs which show a tendency to increase in number, especially toward the free marguis of the valves, by bifurcation and irregular intercalation, ribs marked on top by numerous small, thin, somewhat distant lamelliform imbrications; hinge line almost half as long as the shell, ears like those of islandicus. Dimensions: Altitude, 52 mm.; length, 50 mm.; length of hinge, 23 mm.; convexity of the two valves, 16 mm. Type specimen: No. 107,752 (and No. 7,938 ?) in the U. S. National Museum. Type locality: Middle Pliocene of Pacific Beach, San Diego. M. Pliocene: Type locality; Third Street tunnel, Los Angeles (Arnold); Temescal Canyon, Santa Monica Mountains (Arnold). V. Pliocene: Rincon Creek, Santa Barbara Co. (Arnold) ; Packard's Hill, Santa Barbara (Arnold) ; Fourth and Broadway, Los Angeles (Moody); uppermost Pico of Ventura Co. (Waterfall). ? Pleistocene: Lower San Pedro formation, cold-water zone, of San Pedro (Stanford University collection). This species, although probably related to islandicus, is quite constant in characters and is easily distinguishable. It is most like the living P. patagonicus King, from the Straits of Magellan. Although not common, it is useful in California as an index to the upper half of the Pliocene. The lower Pleistocene record, based on the Stanford Univer- sity collection, is very unreliable. Waterfall has made considerable use of it in his recent work of correlation in Ventura County. Pecten (Pecten) lioicus Dall Pecten (Chlamys) limciis Dall, Amer. Jour. Sci., Ser. 4, Vol. 23, p. 457, text figure on p. 458, 1907; Dall in JNIoffit, Bull. 533 U. S. Geol. Survey, p. 46, 1913; DaU, Prof. Paper 125-C U. S. Geol. Survey, p. 31, 1920. Shell Uke that of islandicus in shape, but almost smooth. Dimensions: Altitude, 61 mm.; length, 55 mm.; length of hinge, 30 mm. Type specimen: No. 110,480 in the U. S. National Museum. Type locality: "Fifty feet below the surface in marine gravels near Nome, Norton Sound, Alaska,"— Otter Creek ? Pliocene: Type locality. Dall states in 1920 that "no further specimens of this very distinct species have come to hand." Perhaps the original specimen is but a monstrosity of islandicus. It looks some- what like living forms of P. squamosus (Gmelin) from Japan upon which the ribs are nearly obsolete; but it has a shorter byssal ear, shallower byssal notch, and straighter anterior margins. Pecten (Pecten) beringianus Middendorff Plate 11, Figure 2 Pecten islandicus var. beringianus Middendorff, "Beitr. Malac. Ross.", Mto. Acad. Imper. Sci., St.-Petersbourg, Ser. 6, Vol. 6, Pt. 3, p. 12, 1849; DaU, Nautilus, Vol. 27, p. 122, 1914; Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919. Pecten (Chlamys) hericeus Gould var. slrategxLs DaU, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 709, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 110, pi. 11, fig. 5, 1903. 166 San Diego Society of Natural History ( Mf.moirs Pectcn {Chlairiys) luialatiDi Sowerby var. slralegiis Dall, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 113, jil. 44, Hks. 2, 2a, 3, 4, 1906; Proc. U. S. Nat. Mus., Vol. 32, p. 54."), pi. .50, fig. 13, 1907, figure rejjroduced in Hull. 31!9 U. S. Geol. Survey, pi. 40, fig. 13, 1907. Pecten (Chlamys) islandicvs beringiamis Middendorff, Dall, Bull. 112 U. S. Nat. iVIu.s., p. 19, 1921; (;)ldroycsfclix Litina^us {Jide Verrill and Bush, Proc. U. S. Nat. Mus., Vol. 20, p. 833, 1898). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 171 Type (by monotypy ?), Ostrea pesfelis Linnaeus, Recent, Corsica, illustrated by Sowerby, Thes. Conch., Vol. 1, p. 67, pi. 17, fig. 162, pi. 20, fig. 234, 1842, and by Reeve, Conch. Icon., Vol. 8, Pecten, pi. 19, species 66, 1853. Shell like that of typical Pallium except that the ears are very imequal, varying from the form of the ears of typical Pecten, in which the byssal ear is roimded on the end, to that of P. pesfelis, in which all the ears are trigonal m shape, the ventral ones large, with an undifferentiated byssal notch, the dorsal ones very small. Geologic range: Miocene to Pliocene (California); Pliocene or Pleistocene of Alaska; Pliocene to Recent in the Orient. Distribution: Warm and temperate waters of the Old World. This section is of doubtful value, but forms the link between Pallium and Chlamys, and seems to have a geographic as well as a morphologic distinction. It inhabits cooler water than typical Pallium, being intermediate in this respect also between Chlamys and Pallium, and is found in parts of the world other than the Orient. Besides the type and P. siviftii with its relatives, the following species should probably be included: P. tigris Lamarck, Philippines; P. sanguinolenta (Gmelin), Red Sea. Pecten (Pallium) hamlini Arnold Peclen {Chlamys) hamlini Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 67, pi. 11, fig. 2, 1906. Type specimen: No. 164,844 in the U. S. National Museum. Type locality: Near head of Slack's Canyon, Mount Diablo Range, Monterey Co. ? Middle Miocene: Type locality, and also near Stanford University, Santa Clara Co. The original specimen of this species is very poor and badly distorted. Specimens in the collection at Stanford ITniversity show that it is a form of the P. siviftii type, dis- tinguishable from the variety parmeleei of that species not by its shape but by its fewer, coarser secondary ribs. Pecten (Pallium) swiftii Bernardi Plate 10, Figures lo. It, 2, 4a, 4b, 5 Pecten sinftii Bernardi, Journ. de Conehyl., Vol. 7, p. 90, pi. 1, fig. 1, pi. 2, fig. 1, 1S58; Schrenck, MoUusken des Amur-Landes und des Nordjapanischen Meeres, p. 487, pi. 21, figs. 1, 2, 3, St. Petersberg, 1867; Dunker, Index Molluscorum Maris Japonic!, p. 242, 1882; Hirase, Cat. Mar. Jap. Sh., p. 33, pi. 3, fig. 15, 1907; Dall, Prof. Paper 125-C U. S. Geol. Survey, p. 31, 1920; Yokoyama, "Foss. Miura Penin." Journ. Coll. Sci., Imper. Univ. Tokyo, Vol. 39, p. 154, pi. 14, fig. 11, 1920; "MoU. Rem. Up. Pt. J6-Ban Coal-field," Journ. Coll. Sci., Imper. Univ. Tokyo, Vol. 45, p. 27, pi. 2, fig. 7, 1925; "Moll. Tert. Basin Chichibu," Journ. Fac. Sci., Imper. Univ. Tokyo, Vol. 1, p. 123, pi. 15, fig. 3, 1925; "Tert. MoU. Shiobara," Journ. Fac. Sci., Imper. Univ. Tokyo, Vol. 1, p. 135, 1926; "Tert. Moll. Oilfields of Embets and Etaibets," Journ. Fac. Sci. Imper. Univ. Tokyo, Vol. 1, p. 245, 1926; "Fos. Sh. from Sado," Journ. Fac. Sci., Imper. Univ. Tokyo, Vol. 1 p. 303, pi. 37, figs. 5, 6, 1926. Peclen {Chlamys) parmeleei Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 708, pi. 37, figs. 14, 14a, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 119, pi. 41, figs. 1, la, 5, 5a, 1906; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, p. 25, pi. 36, fig. 7 (Dall's figure again reproduced), 1907; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907. Shell large, elongate, subtriangiilar in shape; body of the shell ornamented with a few large, more or less prominent folds and small superimposed ribs or striations; the whole surface including the ears covered with a fine sculptural network or cross-hatchmg; free ends of the valves often con- tracted as is characteristic of the subgenus, in many specimens other constrictions at earlier stages of growth giving the main ribs or folds a nodose appearance, superimposed striations worn off when 172 San Diego Society of Natural History [ Memoirs the nodes or ribs are high; hinge line short, sometimes oblique to the axis of the shell; ears varying greatly in size and shape, the byssal notch sometimes moderately deep and the end of the ear arcuate, sometimes almost lacking, with the end of the ear extcndmg obliquely outwards to a point; ears in most specimens very unequal, radially striate, on large shells with five to nine coarse striations, sometimes alternating in size, coarser on the outer edge. Dimensions: Altitude, 105 mm.; longitude, 90 mm.; length of hinge, 50 mm.; convexity of two valves, 35 mm. Type specimen: Of parmeleei, No. 154,479 in the U. S. National Museum. Type localities: Of stviftii, living in Japan; of parmeleei, Pliocene of San Diego. Pliocene: San Diego (as parmeleei, Dall); Crescent City, Del Norte Co. (Arnold; Dall); middle Pico of lo- cality 217a, Holser Canyon, Los Angeles Co., one small, stunted specimen, very well preserved and closer to the typical variety than to any other variety yet described (H. R. G.); Pliocene of various localities in Japan (Yokoyama) . Pleistocene: Of northern Japan (Yokoyama). hiving: Northern Japan, Sea of Okhotsk, Alaska (Yokoyama). "There is a great deal of variation in the form of the ribs which in some specimens are high and prominent, while in others they are low and flattened. Their number, however, is tolerably constant, the main ribs being generally four in the right valve and five in the left. The outline is very characteristic, and the height is invariably greater than the length" (Yokoyama). The number and coarseness of the striations on the major ribs and interspaces, the size, ventricosity, and amount of elongation of the shell are all very variable. The typical form is characterized by moderately high relief, large size, and large ventral ears. Pecten parmeleei Dall, 1898, is the first representative of Pecten swiftii to be described from the Pacific coast of North America. Dall said: "This species is close to P. siviftii Bernardi of Japan but smaller, and differs by the smooth top surface of the ribs, which in P. swiftii are more or less striated or coarsely threaded, and by the not alternated radial riblets on the right posterior ear; also, especially, by the profuse coalescent microscopically checkered squamation which makes a complete external coating of the valve." An examination of a series of living shells from Japan shows that none of these cri- teria is sufficient to separate Dall's species from the living. It is true that Dall's type speci- men is only half as large, but the constrictions on it show that it is less than half as old. The early part of the left valve of Bernardi's type is almost exactly like Dall's type, as shown by the figures. Dall admits that the specimen from the Pliocene of Crescent City, California, figured by Arnold (1906) as parmeleei is indistinguishable from swiftii. The California fossil specimens assignable to the typical variety of swiftii have so far not been very common, which probably accounts for the fact that none have been found so large as the Japanese living specimens selected for collections. Arnold's specimen measures only 70 mm. Dall meant to say in his description the left posterior (or as Arnold has it the left anterior) ear, for the only valve Dall had was a left valve. The dorsal ( = poster- ior) ears are often very poorly developed and in fossils are usually broken off, but when sufficiently developed show radiating ridges as well as the ventral ears ; and even in the liv- ing specimens of swiftii the ridges on the ears are not always alternating in size. Both the living and fossil forms show striations on the main ribs or folds of the body of the shell if the surface has not been worn; but if worn, neither does. The "checkered squamation" or microscopic network is very evident on the living Japanese shells and is of the same character as that on the California Pliocene forms. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 173 Pecten (Pallium) swiftii Bernard! variety etchegoini Anderson Plate 10, Figures 3a, 36 Pecten etchegoini Anderson, Proc. Calif. Acad. Sci., Ser. 3, Vol. 2, p. 198, pi. 18, figs. 92, 93, 1905; Nomland Univ. Calif. Publ. Geol., Vol. 10, p. 219, pi. 7, figs. 1, la, 16, pi., 8, figs. 2, 2a, etc. 1917. Pecten (Chlamys) vattsi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 120, pi. 11, figs. 1, la, 1906; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pi. 35, fig. 1 (same figure), 1907; Arnold and R. Anderson, Bull. 322 U. S. Geol. Survey, p. 59, pi. 25, fig. 4 (same figure), 1907; Arnold, BuU. 396, p. 77, pi. 27, figs. 1, 2, Jan. 15 1910; Arnold and R. Anderson, Bull. 398, pp. 119, 126, 129, 132, 137, pi. 49, figs. 1, 2 (same figures), 1910. Pecten (Chlamys) wattsi var. morani Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 121, pi. 10, figs. 3, 4, 5, 6, 1906. Pecten (Chlamys) uaitsi var. etchegoini Anderson, Arnold, Bull. 396 U. S. Geol. Survey, p. 77, Jan. 15, 1910; Arnold and R. Anderson, Bull. 398, pp. 129, 137, 1910; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. Pecten wattsi Arnold, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. Pecten etchegoini var. waltsi Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 219, pi. 7, eight figures, pi. 8, figs. 2, 2a, 26, 1917. "Pecten ligerrinus Miiller," Yokoyama, "Foss. Miura Penin.", Journ. Coll. Sci., Imper. Univ. Tokyo, Vol. 39, p. 155, pi. 14, figs. 5, 6, 1920, not P. tigrinus MuUer. Pecten cosibensis Yokoyama, Journ. Geol. Soc. Tokyo, Vol. 18 (No. 208), p. 4, pi. 1, figs. 3, 4, Jan. 20, 1911; "Foss. Miura Penin.", Journ. Coll. Sci., Imper. Univ. Tokyo, Vol. 39, p. 156, pi. 13, figs. 7, 8, 1920; "Foss. Shells from Sado, Journ. Fac. Sci.," Imper. Univ. Tokyo, Vol. 1, p. 304, pi. 53, figs. 7, 8, 1926. The variety etchegoini (including the forms wattsi and cosibensis) is recorded from the following localities : ? Miocene: A specimen in the Stanford collection labelled P. hamlini Arnold looks very much like this variety and probably belongs here. It is said to have come from Burial Hill, Los Altos, California. Pliocene: Etchegoin formation of Coalinga (Anderson; Arnold), common in the Pecten coalingensis zone and rare in the Mya japonica zone but not found below (Nomland); Pescadero Creek, one-fourth mile above Jones Gulch, San Mateo Co. (Arnold); Kreyenhagen's Ranch, Fresno Co. (Watts; Arnold); Olinda, Puente HiUs, Orange Co. (Eldridge and Arnold; English) ; middle Pico of locality 217, one specimen, and 217a, two specimens, one of the latter with constrictions as in the form xvaltsi, Holser Canyon, Los Angeles Co. (H. R. G.); middle Pico of locality 228, southeast of Pico Canyon, Los Angeles Co., one very small specimen with constrictions (H. R. G.); northern Japan— Sawan^, rare (Yokoyama). Pecten etchegoini may be distinguishable from swiftii as a variety. It is characterized by coarser striations on the folds and by its generally somewhat stunted form. It is itself very variable, some specimens being relatively much more elongate than the typical swiftii and others much less, some forms lacking the concentric constrictions, whereas on others the constrictions may be abnormally strong. In view of the wide variations in the living variety, it seems of little use to try to separate these forms, some of which are still unnamed, especially as they all occur together and seem to have no significance. Arnold described two of them in 1906, as wattsi and wattsi var. morani, afterwards recog- nizing that the latter is exactly the same as etchegoini. Wattsi is the form with the ab- normally strong constrictions. Arnold also described in 1906 the variety nutteri which has more irregular ribs, the major folds on the right valve dividing in the middle so that they no longer stand out clearly as individuals, and intercalaries appearing on the left valve about equal in size to the main ribs. Nomland (1917) has shown by a series of figures (and specimens and figures of other authors confirm his conclusion) that all these forms intergrade. It is the writers' belief that we have to deal here with a single veiy variable species, on the variations of which almost every possible combination of the many var- iable specific characters is known. Arnold (1910) distinguished wattsi from etchegoini entirely on the basis of stronger concentric constrictions, though the strength of the con- strictions is an individual characteristic dependent upon seasonal changes in temperature or some other environmental factor. The Japanese have recognized in their Pliocene all of these variations and have given them names just as we have, though they do not 174 San Diego Society of Natural History [Memoirs attempt to state the distinctions between their varities and the typical form, which they also recognize. The form nutteri is here separated as a variety, for its relations with the Miocene species may have some significance. Pecten (Pallium) swiftii Bernardi variety nutteri Arnold Pecte7i {Chlamys) milleri Arnold, Prof. Paper 47, U. S. Geo). Survey, p. 67, pi. 11, figs. .3, 4, 4(7, 1906; Bull. 396 U. S. Geol. Survey, pp. 31, 35, 39, pi. 27, figs. 3, 4, 1909; Arnold and Anderson, Bull 398, p. 129, pi. 49, figs. 3, 4 (same figure.s), 1910. Pecten nuUeri Arnold, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. Pecten eichegoini var. nutteri Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 219, pi. 7, figs. 4, 5, pi. 8, figs. 2a, 26, 1917. Pecten heteroglyplus Yokoyama, Journ. Fac. Sci., Imper. Univ. Tokyo, Vol. I, p. 304, pi. 33, figs. 1-6, 1926. Type specimen: No. 6 in the type collection at Stanford University. Type locality: Lower Pliocene near San Gregorio, San Mateo Co., Calif. Pliocene: New Brighton Beach, Santa Cruz Co. (Humphreys); Mt. Hamilton, Santa Clara Co., — Miocene or Pliocene ? (Arnold); Kreyenhagen's Ranch, Fresno Co. (Watts; Arnold); Purisima to Pescadero, San Mateo Co. (J. P. Smith; ^\rnold; etc.); Coalinga (Arnold); common in the Pecten coalingensis zone, not reported from the other zones (Nomland); northern Japan, uppermost Pliocene (Lower Musashino) of Sado Island; also from Kaidate, common, and from the upper horizon at Sawan^, rare (Yokoyama). This variety is characterized by the splitting of the main ribs of the right valve and the development of strong intercalaries on the left valve so that the number of ribs is doubled, or more than doubled, and the shell has an appearance as if it were sculptured by a considerable number of ribs of irregular size, shape, and spacing. A specimen in the the collection at Stanford University from the lower Pliocene of Santa Cruz Co., has an altitude of 85 mm. This variety is not reported from the Pleistocene or Recent, but is represented in older formations by several related forms. It is possible that the other varieties have been derived from this one. Pecten (Pallium) swiftii Bernardi variety kindlei Dall Plate 10, Figure 7 Pecten (Chlamys) suyiflii Bernardi, Dall, Amer. Jour. Sci., Vol. 173, p. 457, 1907. Pecten (Chlamys) kindlei Dall, Prof. Paper 125 U. S. Geol. Survey, p. 30, pi. 6, figs. 2, 7, 1920. This variety is characterized by large size, low surface relief, and low ventricosity. It is found only as a fossil in beds of probable Pleistocene age in Alaska. Section Peplum Biicquoy, Dautzenberg, and Dollfus, 1889 Peplum Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 67, ISSO. Flexopecien Sacco, I Molluschi dei terreni terziarii del Piemonte e della Liguria, Pt. 24, p. 38, Turin, 1897, type P. flexnosns (Poll). Type (by original designation), Ostrea clavata Poll, Recent, distributed from northern Scotland to the Mediterranean; described and illustrated by Sowerby, Thes. Conch., Vol. 1, p. 60, pi. 12, figs. 14, 15, 1842, by Reeve, Conch. Icon., Vol. 8, Pecten, pi. 4, species 18, 1852, and by B., D., and D., op. ciL, p. 68, pi. 16, figs. 10-17, 1889. Shell like that of typical Palliuin hut small, thin, mf)re circular in shape, the radial striation sometimes weak. Volume I J PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 175 Geologic range: Pliocene (possibly Miocene) to Recent (B., D., D.). Distribution: East Atlantic and Mediterranean, Indian Ocean. On some of the thin-shelled, possibly degenerate species of this section, the radial striation is almost obsolete. The relation to Pallium, s. s., is shown by the radiating folds, by the nearly equal ears, and in some individuals by the characteristic contraction of the free margins of the shells. In Peplum, including P. septemradiatus Miiller from Scotland, as well as the type, the ears are short and square as in Pallium, s. s.; but in Flexopecten, including P. flexuosus (PoH), Mediterranean, P. glaber (Linnaeus), Mediterranean, and probably P. parvus Reeve, Mauritius, the ears are somewhat longer and pointed. Prob- ably Flexopecten should be recognized as a section also, having perhaps as much or as little value as Manupecten. This section is included here, although not found in North America, to illustrate the multifarity of form that a group of related Pectens may assume. Subgenus LYROPECTEN Conrad, 1862 Lyropeclen Conrad, Proe. Acad. Nat. Sci., Phila., p. 291, 1862, species in the original list are Pallium estrellanum Con- rad, U. S. Pacific R. R. Survey, Reports, Vol. 6, p. 71, pi. 3, fig. 15, 1857, Lyropeclen volseformis Conrad, new name for Pallium eslrellanum Conrad, U. S. Pacific R. R. Survey, Reports, Vol. 7, p. 191, pi. 3. figs. 3, 4, 1857, and Lyropeclen crassicardo Conrad, described as if new, loc. cil., but probably the same as the Pallium crassi- cardo Conrad, described in the Proc. Acad. Nat. Sci., Phila., p. 313, December 1856; Conrad, Amer. Journ. Conch., Vol. 3, p. 6, 1867; Verrill, Trans. Conn. Acad. Sci., Vol. 10, p. 63, 1897; Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, pp. 695, 701, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 49, 1906. "UTo-peclen" Conrad, Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 105, 1S6S-9; Fischer, Man. Conchyl., p. 944, 1887. Nodipecten DaU, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 695, 1898, type (by original designation) Ostrea nodosa Linnaeus, Pliocene of Florida and living from the Gulf of Mexico to the north coast of South .America, probably also Pacific (as suhiiodosus) . Not to be confused with Lyriopecten Hall, 1883, a Paleozoic form. Type (by subsequent designation, Dall 1898), Pallium estrellanum Conrad, upper Miocene of California. Shell thick, usually large, valves about equally convex: strengthened with large radial ribs upon which and upon the interspaces between which secondary striations are usuallj' developed as on Peden maximus; surface of valves sometimes marked by nodes or concentric constrictions as in Manupecten; ventral ear somewhat longer than the dorsal, with a moderate or characteristically shal- low byssal notch; interior of hinge often marked with strong cardinal grooves. Geologic range: Oligocene or lower Miocene to Recent (Atlantic coast) ; lower Miocene to Recent (Pacific coast). Distribution: warm waters of the Western Hemisphere. Tliis subgenus is in several respects similar to Manupecten; but it is characterized by its longer hinge line with larger ears, and it nearly always has a larger, heavier shell. In spite of the similarities, the two groups probably were derived independently from the section Chlamys of typical Peden, and in their typical development are very distinct. Call's section Nodipecten is based upon distinctions that are of no more than specific significance. The nodose form is represented in varieties of typical species. The large heavy-shelled Pectens that have a parallel development in the Miocene of Europe, Gigantopecten Roverto (+ Macrochlamys Sacco), are said to be distinguishable by their left valves, which are of low convexity, almost as in typical Pecten; but the distinction is of doubtful value and obscm-es a relationship that may be of considerable importance. The Lyropectens appear suddenly and practically simultaneously in the lower Mio- cene of the two sides of the continent. As the correlations between the two regions are 176 San Diego Society of Natural History [Memoirs still somewhat uncertain, it is not yet safe to say positively in which region the new group of Pectens first made its appearance; but the evidence seems to point strongly to the east- ern occurrence being the older. Pecien jeffersonius and its varieties, which are represented in specifically indistinguishable assemblages in the Miocene formations along both the Atlantic and Pacific coasts, are the first Lyropectens to appear in the West, but are pre- ceded in the East by at least one older variety of Pecten jnadisonius, a closely related species. 1 Thus, if it be assumed that the migration of Pecten jeffersonius between the At- lantic and Pacific coasts took a geologically negligible amount of time, it would indicate that the Vaqueros formation, lower Miocene of California, is not so old as the Alum Bluff group of Florida, formerly thought to be upper Oligocene but now considered lower Mio- cene. Conrad and others based their original identification of the Pacific coast Miocene on the presence of Pecten jeffersonius and similar forms. It has been well recognized that there was during the Miocene an inter-oceanic con- nection somewhere in Mexico or Central America through which genera and subgenera and sections of warm-water distribution could migrate; but it has been held highly im- probable, a possibility too "theoretical" to be worth looking into, that any species could migrate through this passageway. However, the evidence is beginning to accumulate and is in some cases sufficiently complete to show that this entirely illogical view is re- sponsible for the neglect of numerous natural facts that would otherwise have been useful for making correlations. In other words, the California province is not so isolated as it has been considered ; some species have been identical on the two sides of the continent, especially at the time when the passageway was open, and in a few cases the species have lived on on one side or the other or even on both sides up to the present day without chang- ing their specific characters sufficiently to become distinguishable. Pecten jeffersonius is an example of an extinct species that once lived on both sides, and Pecten nodosus is an ex- ample of a living species, the Pacific and Atlantic branches of which have remained only doubtfully separable. There are probably many other species in common between the two regions, especially Miocene species, though practically no attempt has been made to recognize them. Because of the similarity of the California Lyropecten assemblage to that of the At- lantic coast, students in California as well as those in the East will find Ball's excellent account of the variations of the eastern species very useful.^ The following is a brief summary of the California Lyropectens, prepared in order to show some of the relations with the eastern species and to show the position of the Plio- cene species within the group. It also serves to illustrate the distinction between Lyro- pecten and Vertipecten. Pecten (L)T:opecten) jeffersonius Say Plate 9, Figure 3 Pecien jeffersonius Say, Journ. Acad. Nat. Sci., Phila., Vol. 4, p. 133, pi. 9, fig. 1, 1824; Conrad, Fossils of the Medial Tertiary, p. 46, pi. 22, fig. 1, 1840, republished by Dall, Philadelphia, 1893. Pecien catiUiformis Conrad, U. S. House of Representatives, Doc. No. 129, p. 20, July, 1855; U. S. Pacific R. R. Survey Reports, Vol. 5, p. 329, pi. 9, 1856, the volume reprinted with explanation of plates by Blake, New York, 1858, Conrad's two versions of the original description collated and the description reproduced by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 171, 1909. Pecten magnolia Conrad, U. S. Pacific R. R. Survey, Reports, Vol. 7, p. 191, pi. 1, fig. 2, 1857, description reproduced by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 181, 1909; Anderson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 100, listed questionably, 1911; Smith, Vol. 3, pp. 165, 173, 178, 1912. ' Pecten (Lyropecten) madiaoniua Say variety sayanus Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3. p. 725, 1898. Chlamys (Lyropecten) aayanua [sic.] Dall, Gardner, Prof. Paper 142-A U. S. Geol. Survey, p. 45, pi. 12, fig. 7, 1926. 2 Trans. Wagner Free Inst. Sci., Phila., Vol. 3. pp. 722-725, 1898. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 177 "Uroyeclen veatchii Gabb" Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 246 (in part, — "Pliocene," Ojai Valley), 1888. Not "Pecten magnolia Conrad" Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 702, 1898; Nautilus, Vol. 14, p. 117, 1901. Pecten (Lyropecten) jeffersonhis Say, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 722, 1898. Pecten (Chlamys) jeffersomus Say, Glenn, Mar>-land Geol. Survey, Miocene Volume, p. 378 (? pi. 100, fig. 2), 1904. Pecten {Lyropecten) magnolia Conrad, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 77. pi. 24, figs. 1, 2, pi. 25, fig. 1, 1906; Proc. U. S. Nat. Mus., Vol. 32, p. 541, pi. 41, fig. 1, 1907; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, p. 14, pi. 28, fig. 1, 1907; Arnold and Anderson, Bull. 322, p. 32, pi. 16, fig. 1, 1907. Shell large, nearly circular, practically equivalve or with the right valve somewhat the more convex; sculptured with 7 to 13 large, strong ribs, which are wider and closer together on the right valve than on the left, the ribs and interspaces alike being marked by numerous scabrous striations; hinge line long, ears large and nearly squarely terminated, sculptured with numerous fine radial stria- tions, the byssal notch small and shallow; interior of the hinge without tlie diverging cardinal grooves that are sometimes found in Lyropectens, or with only rudimentary ones. Dimensions: Altitude, 145 mm.; length, 150 mm.; length of hinge, 105 mm.; diameter of the two valves, 67 mm. Type specimens: Oi jeffersonius, location unknown to writers; of catilliformis — "The specimen was a cast of the interior of the shell and was too friable to preserve. The drawing was made at the locality by Mr. Koppel, and is of the natural size" — Blake; of magnolia, No. 13,311 in the U. S. National Museum (Paratype No. 13,325). Type localities: Oi jeffersonius, Miocene of Maryland; of catilliformis Miocene (prob- ably Anderson's zone A of the Temblor, which might possibly represent the Vaqueros), Ocoya Creek (now called Poso Creek, near Barker's Ranch), Kern Co., Calif.; of mag- nolia, Vaqueros formation, lower Miocene of the Santa Ynez Mts., Santa Barbara Co., California. Lower (?) Miocene: Various localities in the Vaqueros formation of southern and middle California (Arnold). Middle Miocene: 7 Temblor of the east side of the San Joaquin basin, Calif. (Blake; Anderson), possibly Vaqueros; Maryland to North Carolina (DaU). This large characteristic species is a very important marker for the Vaqueros forma- tion in California. It is not surprising that such a form, free-swimming as it was and able to migrate rapidly, should be found on both sides of the continent in approximately the same latitudes in formations that were deposited at a time when the two oceans were connected. It varies greatly in relative dimensions, the most important variety, septen- arius, being also found on both sides of the continent. Variety jeffersonius, s. s. Shell with 9 to 13 ribs, usually longer than high. The type of magnolia appears to belong to this typical variety rather than with the fewer ribbed variety that has often been called magnolia. The two forms intergrade so completely, however, that the distinction may not be important. The ribs on young specimens are high and squarish; but on adults they become rounded, and sometimes flatten out as on the eastern specimen here figured and on two incomplete western speci- mens in the Stanford University collection. Dall distinguishes an eastern variety edge- comhensis Comad with 12 to 17 ribs which approaches closely the eastern P. madisonius Say, although, as Dall explains, it can be distinguished from madisonius by its byssal ear, which is "sculptured with fine uniform numerous threads," and by its notch, which is "shallow and leaves an inconspicuous fasciole." P. miguelensis Arnold resembles edge- comhensis in several respects, including the tendency to have a midrib; and as there are in the Stanford University collection some poorly preserved California specimens from 178 San Diego Society of Natural History [Memoirs an unknown locality that resemble madisonius, it may be possible in the future to show that practically the whole eastern assemblage is represented in California. The more numerous ribbed varieties oi jeffersonius sometimes resemble P. uiagnificus variety crassicardo, and indeed the latter is probably a direct descendant. P. magnificus variety crassicardo can, however, be distinguished by its more numerous ribs, by the fewer, coarser riblets on the ears, and by the strongly developed diverging grooves on the inside of the hinge. Pecten (Lyropecten) jeffersonius Say variety septenarius Say Peclen septenarius Say, Journ. Acad. Nat. Sci., Vol. 4, p. 136, pi. 9, fig. 3, 1824; Conrad, Fos.sils of the Medial Tertiary p. 47 (spelled se-plemnarius), pi. 22, figs. 2, 1840, republished by Dall, Philadelphia, 1893. Pecten jeffersonius var. septenarius Say, Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 722, 1898; Glenn, Maryland Geol. Survey, Miocene Volume, p. 379, pi. 100, fig. 4, 1904. Pecten magnolia Conrad, in part, of California authors. Shell like that of the typical variety but often somewhat narrower, with fewer (7-9), sometimes broader ribs. Dimensions: Altitude, 145 mm.; length, 140 mm.; length of hinge, 105 mm.; diameter of two valves, 65 mm. Type locality: Miocene of Maryland. Lower (?) Miocene: Vaqueros formation near its type locality (Wayne Loel) and in various other places in middle and southern California. This variety intergrades perfectly with the typical variety, but in its extreme de- velopment has quite a distinctive appearance. It is probably from such a form as this that P. nodosus was derived, the latter with its varieties suhnodosus and veatchii being dis- tinguishable by the coarser secondary striations on the ribs, the coarser riblets on the ears, the relatively shorter dorsal ears, the nodosity of the ribs, and the diverging grooves on the inside of the hinge. Pecten (L3Topecten) miguelensis Arnold "Peclen heermanni Conrad," Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 701, 1898 {fide Arnold). Peclen {Lyropecten) miguelensis Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 79, pi. 22, figs. 1, la, 16, pi. 23, fig. 1, 1906. This form is intermediate in general characters between Pecten magnificus variety crassicardo and P. estrellanus, having 17 or 18 prominent rounded ribs which are wider than the interspaces, both the ribs and the interspaces being ornamented by longitudinal striae as on crassicardo, and having a prominent mid-rib as on estrellanus. The left valve of the type is depressed behind the umbones, but this feature is probably not a character- istic of the species. P. miguelensis is distinguished from crassicardo by the wider ribs and narrower interspaces on the right valve and by the mid-rib. From estrellanus it is dis- tinguished by stronger striation, higher, rounder ribs, and larger size. There are in the collection at Stanford University some poorly preserved specimens from the lower or middle Miocene of California, locaUty uncertain, that are marked miguelensis. It is not unlikely that they represent P. madisonius Say, or P. jeffersonius variety edgecombensis Conrad, though the riblets on the ears are coarser. Pecten miguelen- sis originally came from the Miocene of San Miguel Island, and is now considered charac- teristic of the lower Miocene. It may be that P. jeffersonius evolved into the upper Mio- cene forms estrellanus and crassicardo through the form catilliformis ( + the true magnolia, not septenarius) and through this species. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 179 Pecten (Lyropecten) nodosus (Linnaeus) Osirea nodosa Linnaus, Syst. Nat., Ed. 10, p. 697, 1758. Pecten corallinus Chemnitz, Neues Syst. Conch. Cab., Vol. 7, p. 306, pi. 64, fig.s. 609-611, 1874. Osirea decemradiata Gmelin in Linnseus, Syst. Nat., Ed. 13, p. 3329, 1790. Pecten nodosus LinniEUs, Lamarck, Hist. Anim. s. Vert., Vol. 6, p. 170, 1819, Dcsh. and M. Edw. Ed., Vol. 7, p. 139, 1836; Sowerby, Thes. Conch., Vol. 1, p. 66, pi. 15, fig. 115, 1842; Reeve, Conch. Icon., Vol. 8, Perlen, pi. 3, species 15, 1852; Heilprin, Trans. Wagner ¥vee Inst. Sci., Phila., Vol. 1, p. 100, 1887. Pecten corallinoides d'Orbigny in Webb and Berthelot, Histoire Naturelle des lies Canaries, Vol. 2, Pt. 2, p. 102, 1836-44; Sowerby, Thes. Conch., Vol. 1, p. 65, pi. 12, figs. 3, 4, 1842; Reeve, Conch. Icon., Vol. 8, Pecten, pi. 6, fig. 27, 1852. f Pecten fragosus Conrad, Journ. Acad. Nat. Sci., Phila., Ser. 2, Vol. 1, p. 214, pi. 39, fig. 11, 1849. "Pecten magnificus Sowerby" Gabb, Geol. Santo Domingo, p. 256, 1873; Pilsbry, Proc. Acad. Nat. Sci., Phila., for 1921, p. 409, 1922. Pecten pernodosus Heilprin, Trans. Wagner Free Inst. Sci., Phila., Vol. 1, p. 131, pi. 166, figs. 69, 69a, 1887. Lyropecten nodosus Linnseus, Verrill, Trans. Conn. Acad. Sci., Vol. 10, p. 91, 1897. Pecten (Nodipectcn) nodosvs Linnseus, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, pp. 695, 717, 728, 1898; Maury, Bulls, Amer. Paleo., Vol. 5, pp. 350, 442 (or Bull. 29, p. 186, Bull. 30, p. 26), 1917; Vol. 8, p. 59 (or Bull. 34, p. 27), 1920; Woodring, Mem. Geol. Survey of the Dominican Republic, No. 1, pp. 125, 144, 1921. Pecten (Lyropecten) pitlieri Dall, Smithsonian Misc. Coll., Vol. 59, p. 10, 1912; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 23, pi. 17, fig. 6, 1925. Shell of medium or large size, circular, valves of apjjroximately equal conve.xity, sculptured with large rounded ribs, 8-12 in number, with about equal mterspaces, ribs and mterspaces alike marked by numerous rather strong striations, the ribs, especially the largest three of the left valve, periodically interrupted by hollow bulbous nodes; hinge line about half the length of the shell, the ventral ears sometimes twice as long as the dorsal, sculptured usually with five strong riblets, the byssal ear some- times with a few smaller ones on the narrow byssal scar and the others when adult usually with a set of intercalaries almost as large as the primaries and a few additional smaller riljlets toward the base, byssal ear rounding into the rather small V-shaped notch, ctenolium strong; hinge with moderately developed diverging grooves on the inside. Dimensions (Venezuela specimen) : Altitude, 102 mm. ; length, 104 mm. ; length of hmge, 54 mm. ; diameter of the two valves, 40 mm. Type specimen: Of pittieri, No. 214,368 in the U. S. National Museum. Type localities: Of nodosus, African and Indian oceans; of corallinus, Danish West Indies; of corallinoides, Canary Islands; oi fragosus, West Indies; of pernodosus, Pliocene deposits of the Caloosahatchie, Florida; of pittieri, Pleistocene of Costa Rica. Miocene: Dominican Republic (Maury, Woodring). Pliocene: Domincan Republic (Maury); of the Caloosahatchie (Heilprin, Dall). Pleistocene: Antilles and the north coast of South America (Dall); Costa Rica (Dall). Living: East Africa (Linnaeus, Reeve as corallinoides); West Africa (Chemnitz, etc.); Isle of Ascension (Lister); Canary Islands (d'Orbigny); Gulf of Mexico and the Antilles, and probably also (as P. snbnodosns) on the Pacific shores of middle America (Dall). Those who dogmatically assert that no species can occur in widely separated locali- ties will throw up their hands in horror at the distribution cited above. Nevertheless, the shells are there and are so similar that so far as the present writers could discover no one has yet found any characters of more than individual or possibly varietal significance by which to distinguish them. Even if, from the comparison of many specimens, means are found to distinguish the various local groups, the essential and most significant fact will remain that this form has, since the beginning of the Miocene, migrated nearly around the world. If the local groups are separated nomenclatorially, what will be gained by this sacrifice of the expression of the natural history of the group? Pecten gibbus has nearly the same history and distribution. It may be that Pectens, because of their rapid means of locomotion, can travel more widely (provided the climate suits them) than other mol- lusks; but examples of similar occurrences in other genera are coming to light. 180 San Diego Society of Natural History [Memoirs Peden nodosus varies considerably, and it is useful to recognize some of the most dis- tinctive forms as varieties. No attempt is here made to separate any varieties except those that occur on the Pacific coast of America. The species as a whole can be distin- guished from P. jeffersonius by its shorter hinge line and by its coarser radial striations on the ribs and ears. Variety nodosus, s. s. Shell circular, of moderate size and thickness; ribs on the right valve 10 in number, nearly equal in size and character, seldom nodose, ribs on the left valve 9 in number, usually with prominent hol- low bulbous nodes, of which the largest are on the middle rib, the first pair of ribs on each side of the middle rib smaller and with smaller nodes, the second pair large, with large nodes, the third pair small hke the first pair, and the last pair small but with fairly prominent nodes, the larger ribs of the left valve corresponding to wider interspaces on the right. This typical variety is distinguished from the form of subnodostis figured by Reeve only by having one less rib. The specimens in the Oldroyd Collection at Stanford Univer- sity show no other difference, and it is very likely that this one is not of significance. It is almost a certainty that with more material, specimens from the Pacific coast will appear that are indistinguishable from the typical form. Antillean specimens have various colors, carmine, maroon, orange, etc., and Chemnitz mentions among other specimens an orange one from the coast of Guinea, West Africa. It might be mentioned that Chemnitz has an excellent, perhaps the best, description of the typical form of this species, and that his name is binomial, and his illustrations and synonymy very helpful. Hence, if the name nodosus is restricted to the east African form, corallinus should be the name for the West Indian. Dall (1898) gives a good account of the variations in the nodosity of the West Indian form. Pecten (Lyropecten) nodosus (Linnaeus) variety subnodosus Sowerby Pecten subnodosus Sowerby, Proc. Zool. Soc. London, p. 109, 1835; Thes. Conch., Vol. 1, p. 65, pi. 15, figs. 97, 112, 1842; Reeve, Conch. Icon., Vol. 8, Peden, pi. 4, species 20, 1852. "Pecten magnificus Sowerby," on collection labels and sometimes cited in the literature as a synonym of subTwdosus, probably Sowerby's form /3 of magnificus but not the typical form. Shell hke that of the typical variety but with one more rib on each valve, there being two small ribs back of the middle rib of the left valve instead of one, and on the right valve a group of three ribs instead of two back of the wide central mterspace. Dimensions : Like those of the t jrpical variety. LAving: Panama and West Colombia. The present writers follow Reeve's example in selecting Sowerby's form /3 of subno- dosus to bear the name. This variety is represented in the Oldroyd Collection at Stanford University by six Pacific coast specimens, all having the extra rib and all of a maroon color. This variety is exactly intermediate in the rib character between nodosus, s. s., and variety vaughani. Sowerby's form a from the Gulf of California was named intermedius by Conrad, and is somewhat better distinguished from nodosus, but only varietally. Sowerby's form 7 is from the Atlantic, indicating that this variety may also occur in the Atlantic. Reeve's figure is of the left valve and shows more plainly the extra rib. Pecten (Lyropecten) nodosus (Linnseus) variety vaughani Arnold Pecten {Lyropecten) vaughani Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 81, pi. 23, figs. 3, 3a, 36, 1906. "Pecten subnodosus Sowerby," Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 474, pi. 25, fig. 6, 1926. Pecten {Lyropecten) modulatvs Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 11, pi. 3, fig. 6, 1925. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 181 Shell like that of the typical variety but smaller, with two more ribs on each valve, there being two small ribs on each side of the middle rib of the left valve instead of one as in the typical variety, and on the right valve groups of three ribs instead of two on each side of the central wider interspace. Dimensions: Altitude, 37 mm.; length, 39 mm.; length of hinge, 23 mm.; diameter of the two valves, 16 mm. Type specimens: Of vaughani, No. 9, of modulatus, No. 43, in the type collection at Stanford University. Type localities: Of vaughani, Ojai Valley, Ventura Co., probably on the ridge be- tween the Ojai Valley and the Upper Ojai Valley; of modulatus, Pliocene of Scammons Lagoon, Lower California. L. Miocene: Type locality of vavghani. Pliocene: Type locality of nwdulntus; also Coyote Mt., Imperial Co., Calif. (Hanna). This variety is still very poorly known, being represented by only two authentic specimens, and these are probably immature. It is distinguished from the young of the living west Colombia form of subnodosus only by its additional rib in front of the median line, the other differences between the two forms being accounted for by the probable im- maturity of vaughani. The living specimens of subnodosus referred to above sometimes have a slightly stronger riblet in the center of the interspaces, and on the early part of the shell this may be the only riblet. On the type of P. modulatus this middle riblet seems to have been inadvertently accentuated during the excavating of the ribs. In vaughani, on the other hand, the secondary riblets are all worn nearly smooth by natural erosion, being not essentially different from those on the living form. Pecten (Lyropecten) nodosus (Linnseus) variety intermedius (Conrad) Lyropecien intermedius Conrad, Amer. Journ. Conch., Vol. 3, p. 7, 1867. Pecien {Nodipectcn) subnodosus Sowerby, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 128, pi. 52, fig. 1, pi. 53, figs. 1, la, 1906; Bose, Parergones del Inst. Geol. de Mexico, Vol. 2, pp. 41-43, 1907, says the species should be reunited with nodosus. f Pecten subnodosus Sowerby, n. var., Kew, Univ. Calif. Publ. Geol., Vol. 8, p. 46, 1914. Pecten sitbn^)dosus Sowerby, Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924. Pecten {Lyropecten) subnodosus Sowerby, Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 418, 1926; Hanna and Hertlein, Vol. 16, p. 142, 1927. Shell like that of the typical variety, having the same number of ribs, but tendmg to grow larger and heavier, the ribs usually with smaller nodes that are confined to the younger stages of growth, and the secondary striations on the ribs and interspaces becoming more numerous in the adult than on the typical form. Dimensions: Altitude, 150 mm.; length, 165 mm.; length of hmge, 85 mm.; diameter of the two valves, 70 mm. Type specimen: In the U. S. National Museum. Type locality : Cape San Lucas, Lower California. Pliocene: Loreto, Santa Antonita Pt., Coronados Is., Lower California (Hanna and Hertlein); Cedros Island and Turtle Bay, Lower California (Jordan and Hertlein); ? Pliocene of Temescal Canyon, Santa Monica, Los Angeles Co., Calif. (Rivers in Arnold). Pleistocene: Lower Quaternary, Magdalena Bay, Lower California (Jordan); La Paz, Mexico (Bose); upper Pleistocene, coast of Oaxaca, Mexico (collected by R. H. Palmer). Living: Scammons Lagoon, Lower California, to the mainland of Mexico; also reported south to Ecuador (Jordan). Practically all the differences between this form and the typical are functions of its larger size. It is a geographic variety growing larger where the conditions are better suited for it. Smaller specimens have the shape, coloration, and ribbing of the specimen from Zanzibar figured by Reeve as corallinoides. 182 San Diego Society of Natural History [Memoirs The fragmentary specimen reported by Arnold from the upper San Pedro formation of Deadman Island, San Pedro, as a variety with 17 ribs is a P. estreUanus var. cerro- sensis, or possibly a P. magnificus var. crassicardo, but the occurrence is somewhat ques- tionable. The specimen is now in the collection at Stanford University. It may be a re- deposited fragment from an older formation. Pecten (Lyropecten) nodosus (Linnseus) variety veatchii Gahli ? "Pecten nodosus Linnseus," Sowerby, Thes. Conch., Vol. 1, p. 66 in part, pi. 17, fig. 147, 1842. Pecten veatchii Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. .32, pi. 10. fig. .56, 1866. Liropecten veatchii Gabb, Cooper, Seventh Ann. Rept. Calif. St. Mineralogist, p. 246, 1888. Pecten {Nodipecten) veatchii Gabb, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 106, pi. 40, figs. 1, la, 1906. Pecten (Lyropecten) veatchii Gabb, Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 418, 1926. Shell like that of the typical variety or the variety intermedius, with the same number and arrangement of ribs, but with the strong ribs of the left valve unusually liroad and the small ribs un- usually narrow, this character being reflected in the interspaces of the right valve. Dimensions: Altitude, ].30 mm.; length, 145 mm.; length of hinge, 75 mm.; diameter of the two valves, 50 mm. Type specimen: At the University of California. Type locality: Pliocene of Cedros Island, Lower California. Pliocene: Known only from the type locality. f Living: East coa.st of South America (Sowerby). This variety illustrates very well the normal pattern of ribs in the species nodosus, having the differentiation accentuated so that it can be seen more plainly. On some specimens from the type locality there are stronger concentric constrictions which make the right valve appear nodose also, as in some forms of Pecten swiftii and as in the form of typical nodosus called pernodosus by Heilprin. The writers believe that this character is the result of more marked seasonal changes in the environment, and that not being of genetic significance it should not be recognized in the nomenclature. The form with the constrictions occurs with and intergrades with the normal form, and even on the type specimen lesser constrictions are visible. Pecten (Lyropectenj magnificus Sowerby Plate 9, Figure 1; Plate 10, Figure 6 Pecten magnificus Sowerby, Proc. Zool. Soc. London, p. 109, 18.3.5; Thes. Conch., Vol. 1, p. 6.5, pi. 1.5, fig. 114, 1842; Reeve, Conch. Icon., Vol. 8, Pecten, pi. 2, species 9, 18.52. Shell large, circular, sculptured with large rounded ribs as in P. nodosus with moderately strong superimposed striations and sometimes small hollow bulbous nodes on the early part of the left valve, rib arrangement as in nodosus variety vaughoni but with the differentiation usually rather obscure and with one or two extra ];)airs of riljs added at the sides so that the total numl:)er becomes 14 for the right valve and 13-15 for the left; hinge line a little more than half the length of the shell, ears as in vodos^is excejjt that the radial striations are fewer and more distant, three or fom- strong ones on the byssal ear and either four on the others or else the four dividing into eight or nine smaller ones. Dimensions (of large specimen from the type locality): Altitude, 160 mm.; length, 175 mm.; length of hinge, 97 mm. ; diameter of the two valves, 75 mm. Type specimen: In the Museum Cuming, London (?). Type locality : Galapagos Islands. Although this species is obviously related to P. nodosus, it is better distinguished than any of the forms here considered varieties of that species; and yet it has hardly been accorded recognition and has been listed as a synonym or a doubtful variety of nodosus, Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 183 whereas the other forms have sometimes been separated into different sections. It is dis- tinguished from nodosus by its more numerous ribs, by its smaller nodes, and by the sparser striations on the ears, although the last character is not particularly significant, as some Antillean specimens of nodosus, s. s., do not develop the intercalaries and have almost as few riblets. The writers were shocked to discover that typical specimens of crassicardo are indis- tinguishable from living specimens of magnifies except in the one respect that crassicardo seldom has any of the small bulbous nodes. The nodosity appears to increase in P. Tiodosus from higher to lower latitudes, and it is quite probable that the nodosity of the living inagnificus is a result of the warmer water environment. In any case, a comparison of specimens shows beyond any reasonable doubt that the upper Miocene guide fossil in California lived over as inagnificus on the Galapagos Islands; and as the only difference that has developed in the living form may be attributed to the local environment and may not be of genetic significance at all, the latter can hardly be recognized as more than varietally distinct. It is regrettable that such a well-known name as crassicardo has to take a subordinate position; but it seems better to recognize the natural relations than to hide our heads in the sand and try to forget about them. The discovery of a living crassi- cardo or of an upper Miocene magnificus does not in the least injure the value of crassi- cardo in California as an index fossil, for the mollusks in the Tertiary formations are used chiefly as indicators of climatic conditions; and it is apparent that crassicardo migrated southward at the end of the Miocene, giving place to the cooler climates of the Pliocene, and that it can still be used, especially when abundant, as an index to the upper Miocene in California. A recognition of the occurrence of this specific stock in the higher horizons of more southerly latitudes may, if correct, help paleontologists to avoid mistakes in making correlations, especially if more examples are found in later warm-water horizons of southern latitudes. The discovery of a living branch of the crassicardo stock may ex- plain the presence of a 17-rib variety of "subnodosus" in the warm-water upper San Pedro of San Pedro. Variety magnificus, s. s. Shell with small bulbous nodes on the earlier part, especially on the three strongest ribs of the left valve. Pecten (Lyropecten) magnificus Sowerby variety crassicardo (Conrad) Plate 9, Figures 4, 5 Pallium crassicardo Conrad, Proc. Acad. Nat. Sci., Phila., Vol. S, p. 313, December, 18.56, reprinted by Dall, Prof Paper 59 U. S. Geol. Survey, p. 173, 1909. Spondylus estrallensis Conrad, Proc. Acnd. Nat. Sci., Phila., Vol. 8, p. 315, December, 1856, reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 175, 1909, not Pallium estrellanum Conrad, p. 313, ahead of crassicardo. Spondylus estrellanus Conrad, U. S. Pacific Riiilroad Survey, Reports, Vol. 7, p. 191, pi. 1, fig. 3, 1857, description re- printed by Dall, Prof. Paper 59 U. S. Geol. Survey, [>. 182, 1909, not Pallium estrellanum Conrad. Lyropecten crassicardo Conrad, Proc. Acad. Nat. Sci., Phila., p. 291, 1862; .\mer. Journ. Conch., Vol. 3, p. 6, 1867. Liropccten crassicardo Conrad, Gabb, Geol. Surv. Calif., Pal»o., Vol. 2, p. 105, wholly or in part, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 246, wholly or in part, 1888. "Pecten estrellanus Conrad," Cooper, Bull. No. 4, Calif. St. Mining Bureau, p. .57, in part, 1894. "Pecten mognolia Conrad," Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 702 in part, 1898; Nautilus, Vol. 14, p. 117 in part, 1901. Pecten (Lyropecten) diabloeusis .\rnold MS., 1904; Prof. Paper 47 U. S. Geol. Survey, p. 72, 1906, not Pecten diabloensis Clark in Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 176, 1924. Pecten (Lyropecten) crassicardo Conrad, .Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 71, pi. 16, figs. 1, la, pi. 17, figs. 1, la, 1/), pi. IS, figs. 1, 2, 2a, 1906; Proc. U. S. Nat. Mus., Vol. 32, p. .542, pi. 44, fig. 1, 1907; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pp. 14, 147, pi. 31, fig. 1 (same figure), 1907; Arnold and Anderson, Bull. 322, p. 32, pi. 18, fig. 1, 1907; Clark, Univ. Calif. Publ. Geol., Vol. 8, pi. 46, fig. 3, 1915; Hertlein and Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 623, 1927. 184 San Diego Society of Natural History [Memoirs Pecten (lAropeden) crassicardo Conrad, Weaver, Univ. Calif. Publ. Geol., Vol. 5, p. 262, 1909. Pecte7i crassicardo Conrad, Arnold, Bull. 396 V. S. Geol. Survey, pp. 17, 21, 22, 25, 27, pi. 12, fig. 1, Jan. 15, 1910; Arnold and Anderson, Bull. 398, pp. 85, 86, 94, 95, 109, 111, pi. 34, fig. 1, 1910; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 167, 173, 1912; Anderson and Martin, Vol. 4, p. 47, 1914; McLaughlin and Waring, Map Folio accompanying BuU. 69, Calif. St. Mining Bureau, pi. 1, fig. 39, 1914; Clark, Univ. Calif. Publ. Geol., Vol. 8, pp. 419, 426, 435, pi. 45, fig. 3, 1915; Nomland, Vol. 10, pp. 300, 302, 303, 1917; Trask, Vol. 13, pp. 142, 144, 1922. ? Not "Pecten crassicardo Conrad," Guppy, Proc. Agri. Soc. Trinidad and Tobago, Vol. 10, p. 453 (Society Paper No. 440, p. 7), 1910, reprinted in Bulls. Amer. Paleo., Vol. 8, p. 298 (or No. 35. p. 150), 1921 = ? Peclen archon Maury. Pecten (Pallium) liolwayi Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 454, pi. 47, fig. 5, 1915. Peclen crassicardo biformatus Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 307, pi. 18, fig. 1 only (the type), pi. 19, fig. 4, 1917. Pecten (Lyropecten) ricei Trask, Univ. Calif. Publ. Geol., Vol. 13, p. 148, pi. 2, fig. 1 only (the type), 1922. Pecten {Lyropecten) vickereyi Trask, Univ. Calif. Publ. Geol., Vol. 13, p. 148, pi. 4, fig. 1, 1922. Shell like that of the typical variety but without the hollow nodes; ribs varying from 14 to 17 in number. Dimensions: Altitude, 160 mm.; length, 165 mm.; length of hinge, 115 mm.; convexity of the two valves, 65 mm. Type specimens: Of crassicardo, at the Academy of Natural Sciences, Philadelphia; of holwayi, at the University of California; of hiformatus, No. 11,308, of ricei, No. 12,364, at the University of California; of vickereyi, No. 26, at Stanford University. Type localities: Of crassicardo, Monterey Co., Calif., probably upper Miocene; of holwayi, San Pablo Bay, upper Miocene; of hiformatus, Tejon Hills, Kern Co., upper Miocene; of ricei and vickereyi, Briones formation, upper Miocene of the San Francisco Bay district. Middle Miocene: Reported by Arnold and others, but not common. Upper Miocene: Common and characteristic throughout middle and southern California. This variety, as explained above, is not well distinguished from the typical variety, and it would not be surprising to find it along with the typical variety in the Pliocene and Recent of more southerly latitudes. It developed side by side with estrellanus from a form intermediate between it and nodosus, and among the many variations of crassicardo and estrellanus there are a number that approach each other so closely that it is difficult to assign them with confidence to either species. However, the characteristic forms appear to be more common than the intergrades, and it is best for the present to keep the species separate. P. estrellanus is distinguished by its broader, flatter ribs, on the top of which the radial striations are faint, by the inter-rib that is commonly present between the main ribs, and by the more numerous riblets on the ears. The two stocks appear to have been diverging, although the Pliocene variety cerrosensis of estrellanus is again intermediate between them. Some variations of crassicardo, like the ones here illustrated, show a differentiation of the ribs as in nodosus. Pecten (Lyropecten) magnificus Sowerby variety hamiltoni Arnold Pecten {Lyropecten) crassicardo var. hamiltoni Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 73, pi. 11, figs. 5, 6, 1906. ? Pecten {Plagioctenium) neahensis Arnold, Prof. Paper 47, U. S. Geol. Survey, p. 87, pi. 15, figs. 2, 2a, 26, 1906. Shell smaller, with about 17 smaller, rounder ribs, and narrower interspaces. This variety is known from the upper Miocene of middle California ; and if P. neahen- sis, the figure of which is verj^ similar, is included, it occurs also in the middle and upper Miocene of Neah Bay, Washington. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 185 Pecten (Lyropecten) pretiosus Hertlein Pecten (Lyropecten) -pretiosus Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 12, pi. 2, fig. 6, pi. 3, fig. 4, 1925; Hertlein and Jordan, Vol. 16, p. 624, 1927. Shell small, having both valves very convex and contracted around the margins, strengthened with 14 to 16 moderately prrminent rounded ribs, and covered with radial striations. Type specimen: No. 38 in the type collection at Stanford University. This species or pathologic variation is found at several localities in Lower California, at horizons believed to be the equivalent of the lower Temblor (middle Miocene) of Cali- fornia. It resembles very closely Pecten eldridgei, Arnold, and like that species appears to be a stunted or pathologic form of its group. It can be distinguished from eldridgei by its more rounded, more distant, longitudinally striated ribs, and sometimes (but not always) by the more grooved interior of the hinge. Pecten (Lyropecten) estrellanus (Conrad) Plate 8, Figxu-e 4 Pallium estrellanum Conrad, Proc. Acad. Nat. Sci., Phila., Vol. 8, p. 313 (ahead of crassicardo), December, 1856, reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 173, 1909; U. S. Pacific Railroad Reports, Vol. 6, p. 71, pi. 3, fig. 15, 1857, description reprinted by Dall, op. cit., p. 178, 1909; U. S. Pacific Railroad Reports, Vol. 7, p. 191, pi. 3, figs. 3, 4, 1857, description reprinted by Dall, op. cit., p. 182, 1909; not Spondylus estrel- lanus Conrad ( = Pecten crassicardo), V. S. Pacific Railroad Reports, Vol. 7, p. 191, pi. 1, fig. 3, 1857, descrip- tion reprinted by Dall, op. cit., p. 182, 1909. Lyropecten estrellamis Conrad, Proc. Acad. Nat. Sci., Phila., Ser. 2, Vol. 6, p. 291, 1862; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 105, 1868-9. Lyropecten volseformis Conrad, same references as for Lyropecten estrellanus. Liropecten estrellanus Conrad, Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 246, 1888; Bull. No. 4, Calif. St. Mining Bureau, p. 57 in part, pi. 5, figs. 65-67, 1894. "Pecten heermanni Conrad," Dall, Trans. Wagner Inst. Sci., PhUa., Vol. 3, p. 701 in part, 1898; Nautilus, Vol. 14, p. 117, 1901. Pecten (Lyropecten) estrellamis Conrad, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 74, pi. 19, figs. 1, la, pi. 20, figs. 1, 2, 2a, pi. 21, figs. 1, la, lb, 2, 2a, 2b, 1906; Proc. U. S. Nat. Mus., Vol. 32, p. 541, pi. 41, fig. 2, 1907; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pi. 28, fig. 2 (same figure), 1907. Pecten estrellanus Conrad, Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 350, 1908; Bull. 396 U. S. Geol. Survey, pp. 17, 21, 22, 25, 27, pi. 10, fig. 3, Jan. 15, 1910; Arnold and Anderson, Bull. 398, pp. 85, 86, 94, 95, 101, 102, 106, 107, 109, 110, 111, 112, pi. 32, fig. 3, 1910; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 167, 173, 1912; Anderson and Martin, Vol. 4, p. 47, 1914; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 419, 1915; Nomland, Vol. 10, pp. 299, 300, 303, 304, 1917. Pecten (Lyropecten) ricei Trask, Univ. Calif. Publ. Geol., Vol. 13, p. 148 in part, pi. 2, fig. 2 only (probably a worn left valve), 1922. Shell large, biconvex, strengthened with 16 to 20 broad, flat-topped, comparatively low, vertical- sided ribs, with narrower interspaces, each of which usually contains a distinct mid-rib, interspaces on the right valve much narrower than the ribs, containing, as a rule, merely the mid-rib with a narrow groove on each side of it, although on a few specimens there are longitudinal striations on the ribs and interspaces as in migitelensis and crassicardo, especially near the margins of the shell, these striations beuig much fainter and less persistent, only in the interspaces of the left valve are the stria- tions prominent, there being usually one or two au.\iUary striations on each side of the mid-rib ; ears with more numerous radiating riblets than is usual for crassicardo. This species is distinguished from P. miguelensis by its lower, smoother, squarer ribs. From crassicardo it can also be told by its mid-rib. 186 San Diego Society of Natural History [Memoirs Variety estrellanus, s. s. Shell with moderatelj' arched valves and usually about 17 to 19 ribs. Miocene Vacqueros (Arnold 19C9, questionably identified; 8mitli); Temblor (Arnold 1908, listed as Vac- queros; Smith); Briones (Trask); San Pablo (Clark; Arnold; etc.); Santa Margarita (Nomland). Pliocene: Jacalitos (lower Etchegoin) (Arnold 1910) ; lower Pico of locality 2C9, Elsmere Canyon, Los Angeles County, three specimens, one of which is characteristic, the others are somewhat intermediate be- tween this variety and variety caUilin^ (H. R. G.). The form identified by Conrad as Pallium estrellanum in Vol. 7 of the Pacific Railroad Reports and later renamed by him Lyropecten voloBformis has a strongly arched right valve. Conrad thought that the unattached flat valve which he collected with his original speci- men was the left valve, but Arnold has pointed out that he probably was in error. The typical variety, like crassicardo, is reported from the Vaqueros and Temblor, but the early records are doubtful and the species does not become common and branch out into many variations until the upper Miocene. A few stragglers lived over into the lowermost Pliocene. Pecten (Lyropecten) estrellanus (Conrad) variety terminus Arnold Pecten (Lyropecten) estrellanus Conrad variety terminus Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 77, pi. 23i figs. 2, 2a, 1906. Pecten estrellanus var. terminus Arnold, Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 173, 1912; Nomland, Univ. Calif. Publ. Geol., Vol. 9, pp. 81, 203, 204, 205, 208, 1916. Pecten terminus Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 212, 213, 219, pi. 6, fig. 4, 1917. Shell with fewer, broader ribs, usually about 15; rather convex. U. Miocene: San Pablo (Arnold; Smith). L. Pliocene: Jacalitos (Nomland, 1916) ; common in the Chione elsmerensis, and Turitella noi Placopecten Verrill. Trans. Conn. Acad. Sci., Vol. 10, p. 69, 1897, type (by original designation) Pecten cUntonius Say, described in the Journ. Acad. Nat. Sci., Phila., Vol. 4, p. 124, pi. 9, fig. 2, 1824, also described and figured by Verrill. op. cit.. p. 78, pi. 17, figs. 1-7, pi. 20, figs. 7, 8, 8a, pi. 21, figs. 1. la, 2, 2o, =? Pecten mageltanicm Gmelin, Miocene to Recent of the Atlantic coast. 2 Amusium is more closely related to Janira, and it is probable that its apparent relation to Patinopecten is superficial, being a parallel adaptation to a somewhat similar environment. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 193 the characters well. Conrad describes the species as having 17 ribs (living specimens of caurinus have from 16 to 20), and he does not figure nor mention sulcations on the ribs of the right valve, nor interribs between the ribs of the left. It is possible that both healeyi and caurinus occur in the Miocene of the Northwest, or that one or the other, or both, are found there only in the Coos conglomerate, Pliocene or Pleistocene. Pecten (Patinopectenj coosensis Shumard Peden coosensis Shumard, Trans. Acad. Sei., St. Louis, Vol. 1, p. 122, 1858; Gabb, Geol. Survey Calif., Palsec, Vol. 2, p. 122, 1868-9; Arnold and Hannibal, Proc. .A.mer. Phil. Soc, Vol. 52, p. 590, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916; Howe, Univ. Calif. Publ, Geol., Vol. 14, p. 92, 1922; Hertlein and Crickmay, Proc. Amer. Phil. Soc, Vol. 64, p. 267, 1925. Pecten {Patinopecten) coosensis Shumard, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 700, pi. 26, fig. 2, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 61, pi. 6, fig. 2, pi. 7, figs. 2, 2a, 1906; Dall, Prof. Paper 59, p. 112, pi. 16, figs. 2, 2a, pi. 17, fig. 3, 1909. ? Pecten {Patinopecten) cf. coosensis Shumard, Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 417, 1926. Shell large, circular, of low convexity, with 27 to 33 strong ribs, those of the right valve narrow, square or T-shaped with sharp angles, and sometimes with faint medial sulcations, those of the left valve more distant and a little rounded. Dimensions: Altitude, 110 mm.; length, 115 mm.; length of hinge, 54 mm.; diameter of the two valves, 26 mm. Type locality: Empire formation of Coos Bay, Oregon. Upper Miocene: Empire formation of Oregon (Shumard, Dall, Arnold, Howe, etc.); Montesano Formation of Washington (Weaver). f Pliocene: Pliocene of Elephant Mesa, Scammon Lagoon Quadrangle, Lower California, questionably identified (Jordan and Hertlein); Coos conglomerate, Coos Bay, Oregon (Howe). This species is distinguished from P. purisimaensis only by its more numerous ribs. As specimens intermediate even in this respect, having 25-27 ribs, were found and noted by Arnold, it is probable that purisimaensis is directly derived from coosensis. Variety coosensis, s. s. Ribs without lamellar frills. Pecten (Patinopecten) coosensis Shumard variety dilleri Dall Pecten (Lyropecten) dilleri Dall, Nautilus, Vol. 14, p. 117, 1901. Pecten (Patinopecten) dilleri Dall, Arnold, Prof. Paper 47 LT. S. Geol. Survey, p. 62, pi. 5, fig. 2, 1906; Jordan and Hert- lein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 431, pi. 30, fig. 1, 1926. Pecten dilleri Dall, Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 238, 253, 1916. Shell like that of the typical variety but with numerous prominent lamellar frills on the ribs of both valves. Type specimen: In the U. S. National Museum, No. 164,846 (?). Type locality: Lower Pliocene of Rio Dell, Eel River, Humboldt County, northern California. Lower Pliocene: Type locality, lower Wildcat formation (Martin); also Santa Maria district, middle Cali- fornia (Jordan and Hertlein). Middle Pliocene: Elephant Mesa, Lower California (Jordan and Hertlein). It is quite probable that this variety differs from the typical only in the state of pres- ervation. Jordan and Hertlein report the typical form along with dilleri from Lower California, and the specimen reported probably is one on which the frills have been worn off. In the older formations of the Northwest where the preservation is not good, 194 San Diego Society of Natural History [Memoirs it might be expected that the delicate frills would always be destroyed. The fact that the type of P. purisimaensis shows traces of the frills, although on most of the ribs the frills have been completely removed, is instructive. It may indicate, since cooserisis is also a PHocene species, that purisimaensis should be considered another variety of dilleri. Pecten (Patinopecten) purisimaensis Arnold Plate 6, Figure 3 Pecten (Patinopecten) purisimaensis Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 105, pi. 34, fig. 3, pi. 35, figs. 1, la, 1906. Pecten {Patinopecten) tiirneri Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 106, pi. 34, fig. 4, pi. 35, figs. 2, 3, 1906. Pecten purismaensis Arnold, Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 243, 253, 1916. Pecten turneri Arnold, Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922. Shell like that of canrinus, but with 22 to 23 narrower, higher, more sharply angled ribs, ribs sometimes with a slight tendency to be sulcated, and, if not l^adly worn, with lamellar frills somewhat as on dilleri. Dimensions: Altitude, 125 mm.; length, 125 mm.; length of hinge, 50 mm.; diameter of right valve, 18 mm.; of left, 6 mm. Type specimens: Of purisimaensis, No. 3, of turneri, No. 430, in the type collection at Stanford University. Type localities: Of purisimaensis. Pliocene north of the mouth of Pescadero Creek, San Mateo Co.; of turneri, Pliocene of Tomales, Marin Co., California. Pliocene: Merced-Purisima formation, north and south of San Francisco, type localities of the two names. This species resembles caurinus very closely, and is sometimes hard to tell from it. On the other hand, it is very much like P. coosensis Shumard, being distinguished prin- cipally by its fewer ribs. The lamellar frills, resembling those of coosensis variety dilleri, emphasize the relationship with that species and suggest that the sharp-angled ribs and the frills go together, the latter in purisimaensis having usually been removed by erosion. The type of P. turneri is a small, poorly preserved specimen with narrow ribs on which the sulcations are a little stronger than usual. Pecten (Patinopecten) caurinus Gould Plate 6, Figure 4 ? Pecten propatuliis Conrad 1849 (see heading for). Pecten caurinus Gould, Proc. Bost. See. Nat. Hist., Vol. 3, p. 345, 1850; U. S. E.\-ploring Exped. (Wilkes), Vol. 12, p 458, 1852, Mollusca Atlas, pi. 42, figs. 569, 569o, 5696, 1856; Kuster and Kobelt, in Martini-Chemnitz Syst Conch. Cab., Ser. 2, Vol. 17, Pt. 2, Spondylus und Pecten, p. 152, pi. 43, fig. 1, 1888; Williamson, Proc, U. S. Nat. Mus., Vol. 15, p. 193, 1892; Keep, West American Shells, p. 38, 1904; .\rnold and Hannibal, Proc Amer. Phil. Soc, Vol. 52, pp. 593, 594, 596, 1913; McLaughlin and Waring, Map Folio accompanying Bull 69 Calif. St. Mining Bureau, pi. 1, fig. 47, 1914; Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 239, 253, 1916 Pecten heermarmi Conrad, Proc. Acad. Nat. Sci., Phila., Vol. 7, p. 267, 1855; not "Pecten (Lyropecten) heermanni Conrad," Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 701, 1898, nor "Pecten heermanni Conrad" Dall, Nautilus, Vol. 14, p. 117, 1901. Pecten meekii Conrad, Proc. Acad. Nat. Sci., Phila., Vol. 8, p. 313, December, 1856; U. S. Pacific R. R. Survey, Re- ports, Vol. 7, p. 190, pi. 1, fig. 1, 1857, the descriptions in these two publications reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, pp. 173, 181, 1909. Amusium caurinnm Gould, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 595, 645, 679, 1864, reprinted in Smithsonian Misc. Coll., No. 252, pp. 81, 131, 165 (bottom pagination), 1872; ? DaU, Proc. Calif. .\cad. Sci., Vol. 5, p. 296, 1874; Cooper, Seventh Ann. Rept. Calif. St. Mineralogist, p. 228, 1888; Keep, West Coast Shells, p. 168, 1888, 1892. Not "Pecten caurinus Gould," Dall, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 12, p. 216, pi. 5, fig. 4, 1886, reprinted in Bull. 37 U. S. Nat. Mus., pi. 5, fig. 4, 1889, 1903, = P. vancouverensis Whiteaves; ? Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, p. 25, 1907; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; English, Univ. Calif. Publ, Geol., Vol. 8, p. 212, 1914. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 195 "Peclen propatulus Conrad," Cooper, 7th Ann. Kept. Calif. St. Mineralogist, p. 258 in part, 1888; Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 238, 253, 1916. Peden {Palinopecten) caurinns Gould, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 710, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 107, pi. 13, fig. 6, 1903; Prof. Paper 47 U. S. Geol. Survey, p. 101, pi. 38, figs. 1, la, 16, pi. 39, figs. 1, 2, 1906; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pi. 36, fig. 1, (not p. 25) 1907; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 45, 1916; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 19, pi. 25, fig. 1, pi. 26, fig. 1, 1924; WaterfaU, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Peden (Peden) merriami Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 99, pi. 30, figs. 1, la, 2, 1906; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, p. 24, pi. 36, fig. 9 (not a figure of the type), 1907. Peclen (Chlamys) caurinus Gould, Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 57, pi. 6, fig. 1, pi. 4, fig. 1, 1924. Pecten oregonensis Howe, Univ. Calif. Publ.Geol., Vol. 14, p. 98, pi. 11, figs. 1, 2, pi. 12, figs. 1, 2 (aU right valves), 1922. Shell large, thin, of nearly circular outlme, valves of very low convexity, sometimes nearly equal, sometimes with the right valve moderately arched and the left valve flat or only slightly convex near the umbo and on large specimens concave beyond; ribs varying from 16 to 20 m number, smooth, on the right valve squarish and equal to or -wider than the interspaces, rarely showing a very faint medial sulcus, on the left valve narrow, distant and rounded or triangular, most of the interspaces without inter-ribs, the whole surface of the shell, except where worn, covered with very fine engraved gro^^'th Imes; huige line varymg considerably m relative length, sometimes half the length of the shell, sometimes nearly three-fifths, ears almost equal m length, not deep, practically without sculpture except for growth hues, byssal notch moderately deep, leavmg behind it a distmct scar. Dimensions: Altitude, 160 mm.; length, 162 mm.; length of hinge, 87 mm.; diameter of right valve, 20 mm. ; of left, 5 mm. Tijpe specimens: Of caurinus, No. 5,954, of meekii, No. 13,333, in the U. S. National Museum;of/}eenwanni in the Academy of Natural Sciences, Philadelphia (^de Arnold), not U. S. Nat. Mus. No. 13,317; of merriami, probably destroyed in the San Francisco earthquake, a specimen from the Arnold collection of Stanford University having all the characters of merriami, and labelled merriami. Pliocene of Ventura County, hereby designated the neotype; of oregonensis. No. 25 in the Stanford type collection. Type localities: Of caurinus, living, Puget Sound; of meekii and heermanni, near Santa Barbara, probably uppermost Pliocene ; of merriami, upper or middle Pliocene of Santa Felicia Canyon, a tributary of Piru Canyon, Ventura County; of oregonensis, Empire formation or Coos conglomerate, Coos Bay, Oregon. f Miocene: Middle Miocene of Oregon and Washington (Carpenter, Dall, Arnold and Hannibal, etc., as propatulvs) ; upper Miocene, Empire formation (Howe, £is oregonensis). Pliocene: Lower Wildcat formation of northern California (Martin as propahihis; Howe as oregonensis, etc.); ? middle Pliocene of San Diego (Dall, — the present wTiters question this occurrence very strongly, the species reported being almost surely healeyi); middle or upper Pliocene of Ventura County (Arnold as merriami); uppermost Pliocene of Ventura Co., abundant and characteristic, found at Iocs. 225, 218, 241, etc., S. D. S. N. H. (H. R. G.), and in numerous other places at the top of the Pliocene clay shale; uppermost Pliocene of Santa Barbara (Arnold); Eel River and nearby localities in Humboldt Co., northern California (Arnold) ; Coos conglomerate of Oregon (Howe) ; mouth of Raft River, Jefi'erson Co., Washington (Arnold). Pleistocene: "Pliocene" and lower San Pedro series of San Pedro and vicinity (Arnold). Linng: Wrangell Island, Alaska, to Siletz Bay, Oregon (Dall); San Pedro (Williamson). It is unfortunate that the well-known name caurinus is threatened by the earlier name propahilus, no real attempt ever having been made to separate the two. Dall states that propatulus has only 15 ribs, whereas Conrad's original description expressly states that it has 17; and Dall states that caurinus has from 20 to 26 ribs, whereas the writers have not noticed in 25 Pliocene and Recent specimens examined a single one with more than 20 ribs (unless the side margins be counted), and the normal number is about 18. Carpenter, whose observations are usually much more accurate than Dall's, con- sidering the scant material he had to work with, makes the following note : 19G San Diego Society of Natural History [ Memoirs "Pecten propatulus, Conr. A very fine specimen, enclosed in a large nodule from Oregon, was presented to the Brit. Mus. by Mr. C. Pace. If not identical with Amusium caurinum Gld., it is most closely allied, especially to the Japanese form." By the Japanese form. Carpenter meant P. yessoetisis Jay,^ which he considered a variety of caurinus; and there is much to be said for Carpenter's suggestion that -pro- patulus may be closely related to yessoc7isis. P. yessoensis is distinguished by the fine network sculpture covering the surface of the shell and by its smaller apical angle, which usually causes the shell to be relatively shorter and to have on the average a few less ribs, and which also causes the ears to be deeper. Occasionally yessoensis has a mid-rib in one or two of the interspaces of the left valve and a corresponding tendency in the ribs of the right to be slightly grooved; but this irregular feature is also noted in caurinus, and the height of the ribs and the width of the interspaces vary as in caurinus. Thus, if the form represented by the holotype of propatulus has the same minor sculpture that the paratypes (or plesiotypes of propatulus) figured by Arnold and Dall have, then propa- tulus is distinguished. from caurinus by practically the same characters that yessoensis is, and the relationship is evident. There are other fossil species of Patinopecten in Japan that might help to link the two. Hence, for the time being caurimis is considered distinct from propatulus, though the separation should not be made on the basis of a misstatement of the number of ribs. There is in the collection at Stanford University a large series of very fine specimens of caurinus from the Pliocene or Pleistocene of Eel River, northern California. Pecten caurinus is a very important and characteristic fossil in the uppermost Plio- cene of southern California. Its value lies not in its being confined to the uppermost Pliocene but in its being a characteristically cold-water species. Its abundance in the uppermost Pliocene is indicative of the colder temperatures of the time. It also occurs commonly in southern California in the cold-water horizons of the lower Pleistocene, probably during the glacial periods, and also throughout the Pliocene and possibly in the upper Miocene (Empire formation) of the Northwest. The warmer water species which precedes it in southern California, P. healeyi, is distinguished by grooves on the ribs of the right valve and by the inter-ribs which are almost invariably present on the left valve. These two species can be used nearly always in southern California to distinguish the middle Pliocene from the upper, or Santa Barbara, zone. Pecten (Patinopecten) healeyi Arnold Plate 6, Figures 2a, 2b ? Pecten jwopatuhis Conrad (see heading for). Pecten expansus Dall, Proc. U. S. Nat. Mus., Vol. 1, p. 14, 1879; Rivers, Bull. So. Calif. Acad. Sci., Vol. 3, p. 69, 1904; not Pecten expa7isus Smith, Quart. Journ. Geol. Soc, Vol. 3, pp. 413, 419, pi. 18, fig. 21, 1847. Pecten (Patinopecten) expansus Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 706, pi. 26, fig. 1, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 108, 1903. Pecten (Patinopecten) healeyi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 103, pi. 36, figs. 1, la, pi. 37, figs. 1, la, 2, 1906, new name for expansus Dall; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pi. 34, fig. 1, 1907; Arnold and Anderson, Bull. 322, p. .59, pi. 26, figs. 1, 2, 1907; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 4.'5, 1916; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 417, 1926. Pecten healeyi Arnold, Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pp. 25, 153, 1907; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, pp. 210, 213, 1914; McLaughlin and Waring, Map Folio accompanying Bull. 69 Calif. St. Mining Bureau, pi. 1, fig. 42, 1914; Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 243, 253, 1916; Nomland, Vol. 10, pp. 212, 219, 1917; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. ' Pecten yessoensis Jay. V. S. Japan Exped., Vol. 2. p. 293. pi. 3, figs. 3, 4, pi. 4. figs. 1, 2, 185G. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 197 ? Peden yamasakii Yokoyama, Journ. Fac. Sci., Imper. Univ. Tokyo, Sec. 2, Vol. 1, p. 17, pi. 5, figs. 1, 2, 4, 5, 1925. ? Peden tryblium Yokoyama, Journ. Fac. Sci., Imper. Univ. Tokyo, Sec. 2, Vol. 1, p. 17, pi. 6, figs. 1, 2, pi. 7, figs. 1, 5, 1925. Shell with the general outlme of caurinuf:, usually equivalved, with 17-21 ribs; the ribs of the right valve wider than the interspaces and always distinctly sulcated after the shell has reached a height of about 50 mm., the ribs of the left valve like those of cauriiius, but after the shell has reached 50 mm., always separated bj^ a strong mid-rili, the mterspaces of the right valve often with an ob- scure mid-rib also; hinge line about half the length of the shell, ears as in caurinus except that there are four or five fairly strong radiating rililets on the byssal ear; growth lines as in caurinuf;. Dimensions (of the rather small figured specimen) : Altitude, 85 mm. ; length, 86 mm. ; length of hinge of right valve, 40 mm. ; of left valve, counting the bulge behind the byssus, 45 mm. ; convexity of valves, 8 mm. each. Type specimens: Of expansus, No. 7,941, of healeyi (designated by Arnold in the explanation of plates), No. 148,012, in the U. S. National Museum. Type locality: Pliocene of San Diego. Lou-er Pliocene: Elsmere Canyon, Los Angeles Co. (Arnold; English), at loc. 206 S. D. S. N. H., Elsmere Canyon, four incomplete specimens (H. R. G.); (? lower) Pliocene of Brea Canyon, 4 miles S. E. of Newhall, Los Angeles Co. (Arnold). Middle Pliocene: Pacific Beach, San Diego (Dall; Arnold; etc.) common; Tia Juana, Mexico (Greeley in .Ar- nold); Cedros Island, Lower California (Jordan and Hertlein); Temescal Canyon, Santa Monica Mountains, common (Rivers in Arnold); Purisima formation, San Mateo Co., middle California, common (Arnold); occurring commonly in the northern part of Los .\ngeles Coimty along the out- crop of the middle Pliocene from Newhall tunnel to Pico and Holser canyons, being represented at localities 211-214, 257, 26;5, 228, 217, etc., S. D. S. N. H. (H. R. G.); doubtfully reported from the "lower" ( = middle) Pico of Ventura County (Waterfall). f Upper Pliocene: Fourth and Broadway, Los Angeles (Moody); ? Jajjan (Yokoyama). This species is an important horizon marker in southern California, disappearing rather suddenly with the first wave of the colder temperatures of the upper Pliocene, and giving place to P. cauriynis. Like caurinus, the name is threatened by the poorly- known propatulus, for both simple-rib and split-rib forms have been identified as propa- tulus. There is nothing to distinguish healeyi from the paratypes of propatulus illustrated by Arnold and Dall except the microscopic cross-hatched minor sculpture of the latter. P. healeyi is distinguished from caurinus by the split ribs of the right valve and the inter- calaries between the ribs of the left. Variety healeyi, s. s. Shell usually nearly equivalved, with 17-21 ribs, the sulcations on the ribs of the right valve and the intercalaries on the left valve becoming only moderately strong. Pecten (Patinopecten) healeyi Arnold variety lohri Hertlein Plate 6, Figures In, 16 "Pecten pabloensis Conrad," Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 258 in part, 1888. Peden {Palinopeclen) oweni Arnold, Prof. Paper 47 L'. S. Geol. Survey, p. 63, pi. 8, figs. 1, lo, lb, 1906; Arnold and Anderson, Bull. 322 U. S. Geol. Survey, p. 59, pi. 25, figs. 2a, 26, 1907; .\rnold. Bull. 396, pp. 25, 27, 31, 35, 39, 42, pi. 23, fig. 1, Jan. 15, 1910, repeated in Bull. 398, pi. 45, fig. 1, 1910; not Pecten oweni De Gregorio, Naturalista Siciliano, Ann. 3, p. 133, 1884. Peden oweni Arnold, English, Univ. Calif. Publ. Geol., Vol. 8, pp. 210, 213, 1914; McLaughlin and Waring, Map Folio accompanying Bull. 69 Calif. St. Mining Bureau, pi. 1, fig. 40, 1914; Nomland, Univ. Calif. Publ. Geol., Vol. 9, pp. 81, 203, 1916; Martin, pp. 232, 243, 245, 253, 1916; Nomland, Vol. 10, pp. 212, 219, 1917. Peden {Paiinopeden) lohri Hertlein, Nautilus, Vol. 41, p. 93, January, 1928, new name for Peden oweni Arnold not De Gregorio. 198 San Diego Society of Natural History [Memoirs Shell like that of the typical variety but with the right valve more strongly convex and the left usually convex only on the early part, thereafter concave, ribs fewer m number than in the typical variety (14-16), the sulcations on the ribs deeper, and the mtercalaries between the ribs on both valves stronger. Dimensions : Altitude, 95 mm. ; length, 100 mm. ; length of hinge, 50 mm. ; diameter of right valve, 17 mm. ; of left valve, 6 mm. Type specimen: At the University of California. Type locality: Foxin's, Santa Barbara County, probably Pliocene. ? U. Miocene: Possibly San Pablo formation near Double Eagle wells, Coalinga district, middle California (Arnold); a variety 2 miles south of San Lucas, Monterey Co. (Arnold). Lower Pliocene: Santa Maria district (Arnold and Anderson); Puente Hills, Los Angeles Co. (.\rnold); Elsmere Canyon, Los Angeles Co. (English), localities 209 and 210 S. D. S. N. H., Elsmere Canyon, twenty-three specimens (H. R. G.); locality 227, south of Humphreys Station, Los Angeles Co., three specimens (H. R. G.). Middle Pliocene.: Temeseal Canyon, Los Angeles Co. (Arnold) ; Purisima formation, middle California (Ar- nold); Merced formation, middle California (Martin). This variety, as Arnold pointed out, is closely related to the typical variety. The two varieties often occur together, but sometimes the variety lohri is more common in older horizons. The upper Miocene occurrences are somewhat doubtful. In the convexity of the valves, lohri is similar to the form merriajni of caurinus, which appears to be of no significance. It is the left valve of these forms that is nearly flat, not the right as in the somewhat closely related Vertipectens. Subgenus AEQUIPECTEN Fischer, 1886 Aequipecten Fischer, Man. Conchyl., p. 944, 1886; Verrill, Trans. Conn. Acad. Sci., Vol. 10, p. 67, 1897; Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 695, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 49, 1906. Type (by monotypy), Ostrea opercularis Linnaeus, living from Norway to the Mediter- ranean and illustrated in all the principal works dealing with living Pectens, full synonymy and illustrations of variations given by Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 72, pis. 17, 18, 1889. Shell of moderate size and thickness, of circular outline; ribs miiform, distinct, not bifurcating, sometimes with finely imbricated radial striations; ears usually nearly equal, the byssal notch of moderate depth, ctenolium usually present but small. Geologic range : Jurassic to Recent. Distribution: Warm and temperate waters of all oceans. This subgenus is closely related to Chlamys, with which it appears to intergrade ; but it can be distinguished by its fewer, more distinct ribs, which are characteristically with- out striations, by its circular outline, and by its nearly equal ears with a smaller byssal notch. It has representatives in the middle, and possibly in the early Mesozoic, although it is quite probable that it has not kept separate from Chlamys during all the time since then but may have been added to by other species of Chlamys that have evolved inde- pendently into a similar form. In other words, the division may be merely a makeshift one, useful for the present until we know more about the group. It was on one of the Aequipectens, Pecten gibbus variety irradians Lamarck, that Jackson made his most extensive study of the phylogeny of the family.' In 1898 Dall split off the section Plagioctenium, describing it as "Resembling Aequi- pecten but without radial striation." The other characters that Dall mentions apply 1 See above, under the discussion of the Pectinidse. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 199 equally well to Aequipeden, s. s. In view of the fact that P. opercularis is very similar to Pecten gibbus variety irradians and that P. purpuratus and other species assigned to Plagioctenium sometimes show the radial striation, it seems somewhat questionable whether Plagiocteniuvi should be accorded even sectional value. Pecten exasperatus (Lin- nseus) from Florida has a ventricose form, long hinge line, and fairly strong ribs (charac- ters often cited as distinguishing Plagioctenium) ; but it also has strong radial striation. Leptopecten and Lissopecten are degenerate forms clearly derived from Aequipecten, and should not be given more than sectional rank. The subgenus Aequipecten has been slighted by California conchologists and paleon- tologists because Arnold gives as its sole representative Pecten (Aequipecten ?) palmeri Dall,' a very peculiar species, the type of which (U. S. N. M. 150,980) looks like the left valve of a very unusual Chlamys, having sculpture somewhat like that of the left valve of hastatus, but with ears more like those of an Aequipecten. The right valve figured by Arnold is probably a specimen of Leptopecten, perhaps tumbezensis d'Orbigny, the reason for assigning it to palmeri not being apparent. On the other hand, several Pacific coast Tertiary species are so close to P. opercularis that they can hardly be separated speci- fically. Section Aequipecten, s. s. Valves not verj' convex, the right one sometimes nearly fiat; sculptured with distinct, but low, rounded, usually rather distant ribs, radial striations of variable strength but never very prominent. Pecten (Aequipecten) pabloensis Conrad Pecten pabloensis Conrad, U. S. Pacific Railroad Survey, Reports, Vol. 6, p. 71, pi. 3, fig. 14, 1857, description reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 178, 1909; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 258 in part, 1888, Dall, 17th Ann. Rept. U. S. Geol. Survey, p. 844, 1896. Pecten (? Plagioctenium) pabloensis Conrad, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 703, 1898. Pecten (Plagioctenium) pabloensis Conrad, .Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 88, pi. 27, figs. 5, 5a only, 1906. Pecten (Chlamys) pabloensis Conrad, Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 452, pi. 47, fig. 8, pi. 48, fig. 2, 1915. Pecten (Plagioctenium.) bilinealvs Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 448, pi. 64, figs. 3, 4, 1915. Pecten Ulinealus Clark, Trask, Univ. Calif. Publ. Geol., Vol. 13, pp. 142, 145, 1922. Shell rather small, thin, circular, with low, narrow ribs and a suggestion of an intercalary thread, both valves usually somewhat humped up and distorted ; internally with strong, sharp radial lirse as in Amusium; otherwise like P. discus. Dimensions: Altitude, 30 mm.; length, 31 mm.; length of hinge, 15.5 mm.; convexity of right valve, 4 mm. ; of left valve, 5 mm. Type specimen: At the Academy of Natural Sciences, Philadelphia (?). Type locality: San Pablo formation, upper Miocene, San Pablo Bay, Contra Costa County, middle California. Miocene: Alaska (Dall, 1896); upper Miocene, type locality; Briones formation, upper Miocene, of middle California (Trask). This species appears to be a degenerate offshoot of P. discus, with which it occurs and with which it intergrades. The humped-up form may have been caused by the influx of more or less fresh water, and this suggestion is strengthened by the fact that pabloensis sometimes occurs very abundantly all by itself in beds two or three feet thick. The writers should probably have considered this form a variety of discus, were it not that its name has priority. It is inconvenient to class a normal species under the name of a degenerate ' Pecten palmeri Dall, Nautilus, Vol. 11, p. 85, 1S97. Peclen (.Aequipecten) palmeri Dall, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 136, pi. SO, figs. (2, 2a?), 3, 3a, 1906. 200 San Diego Society of Natural History [Memoirs variety. Furthermore, the observation noted below made it desirable to keep this form separate. The most interesting character of P. pabloensis is its possession of strong Amusium- like internal lirse, which are stronger than the external ribbing, and which cause on inter- nal casts the two lines of bilineatus. These lirse are of the same nature as those on the interior of P. hyalinus (Poli), which Verrill noted and thought so remarkable that he pro- posed for that species the new name Lissopecten.^ The writers do not venture to say whether P. pabloensis is specifically related to P. hyalinus or not; but they take pleasure in noting that this occurrence is a very satisfactory confirmation of Ball's observation that Lissopecten is "merely a somewhat degenerate Aequipecien." This occurrence also helps to indicate the mode of origin of the internal lirse of Amusium. The Pleistocene and Recent P. hyalinus of the Mediterranean is well discussed and illustrated by Bucquoy, Dautzenberg, and Dollfus.'^ Pecten (Aequipecten) discus Conrad Plate 4, Figure 7 Pecten discus Conrad, U. S. Pacific Railroad Survey, Reports, Vol. 7, p. 190, pi. 3, fig. 1, 1857, description reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 181, 1909; Gabb, Geol. Survey Calif., Pateo., Vol. 2, p. 122, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 257, 1888; Calif. St. Mining Bureau, Bull. No. 4, p. 57, pi. 4, figs. 55, 56, 1894. Pecten {Chlamys ?) discus Conrad, Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 704, 1898. Pecten (Plagioctenium) discus Conrad, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 86, pi. 27, figs. 1, lo, 2, 3, 4, 1906. "Pecten {Plagioctennim) pabloensis Conrad," Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 88 in part, pi. 27, figs. 6, 6a, 7, 1906. Pecten {Pecten) cierboensis Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 449, pi. 47, fig. 6, 1915. Pecten (Pecten) raymondi Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 450, pi. 46, figs. 1, 2, pi. 47, figs. 1, 2, 1915. Pecten raymondi Clark, Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 301, 302, 303, 304, 1917; Trask, Vol. 13, pi. 1, figs. 4, 5, 1922; Kew, Bull. 753 U. S. Geol. Survey, pp. 68-69, 1924. Pecten (Pecten) raymondi brionianus Trask, Univ. Calif. Publ. Geol., Vol. 13, p. 148, pi. 1, figs. 2, 3, 1922. Shell of moderate size, outline circular, the valves of very low convexity, the right valve only half as convex as the left; shell sculptured with 17 to 20 low, smooth, rounded ribs of variable width; hinge line variable, about half the length of the shell, ears of nearly equal length, the ventral ears shghtly longer, byssal notch moderately deep, narrow, leaving behind it a narrow sunken scar, byssal ear sculptured with three to five moderately strong riblets, other ears with numerous fine weaker riblets. Dimensions: Altitude, .54 mm.; length, 56 mm.; length of hinge line, 28 mm.; convexity of the right valve, 5 mm.; of the left, 10 mm. Type specimens: Of discus, No. 13,335 in the U. S. National Museum; of cierboensis, at the University of California; of raymondi, No. 11,581, of brionianus. No. 12,368, at the University of California. Type localHies: Of discus, between La Purisima and Santa Ynez, Santa Barbara Co., probably from the Monterey formation, middle Miocene; of cierboensis and raymondi, San Pablo formation, upper Miocene of middle California; of brionianus, Briones forma- tion, middle or upper Miocene of middle California. Middle Miocene: Tj-pe locality of discxts; San Luis Obispo Co. (Arnold), etc. Upper Miocene: Type localities of raymondi and brionianus; Santa Margarita formation at its type locality, also north of Coalinga, on the Nacimiento River, and in the Tejon Hills (Nomland); Modelo ? for- mation, now considered Santa Margarita from hill west of forks in Haskell Canyon and east ( = west ?) of Los Angeles reser\-oir in Dry Canyon, Los Angeles Co. (Kew); common in the basal sand- stone beds of the Santa Monica Mts., Los Angeles Co. (Kew) ; Santa Margarita of well cores in the southern end of the San Joaquin basin (H. R. G.). » Lissopecten Verrill, Trans. Conn. Acad. Sci., Vol. 10, p. 68, 1897, type (by original designation) Ostrea hyalina Poli; Dall, Trans. Wagner Free Inst. Sci.. Phila., Vol. 3, pp. 698, 744, 1898. 2 Mollusques .Marina du Roussillon. Vol. 2, p. 96, pi. 21, figs. 11-17, 1889 Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 201 This species is so close to Pecien opercularis that there can be no reasonable doubt that either the two are descended from the same immediate specific ancestor or that one is derived directly from the other. Indeed, when the group is better known, it may be desirable to put discus into the synonymy of opercularis, or at least to call it a variety, recognizing in this case as in many others a migration between Europe and California during the Miocene. P. discus is distinguished from opercularis by the absence (possibly due to the state of preservation) of the dehcate radial striations superimposed on the ribs of that species, and perhaps by a slightly deeper byssal notch. There are living varieties of opercularis on which the striations amount to little more than color markings. There has been some question about the application of the name discus, and Dr. Clark of the University of California has thought that the name should apply to a middle Miocene species, possibly andersoni Arnold, distinct from the upper Miocene form which he called raymondi. It is true that andersoni and discus (as here considered) are very similar and that andersoni is difficultly separable on the basis of fewer ribs, smaller size, and narrower byssal ear; but in all these characters (except the last, which Conrad does not mention), the original description agrees better with discus as identified by Arnold and by the present writers than it does with andersoni. Conrad states that his species has 17 ribs, and is two inches high. In both species the ears are of nearly the same length and the right valves more nearly flat than the left. Conrad's illustration is of no use at all, but Arnold figures the type specimen, or at least what is said to be the type specimen. Furthermore, discus was described from shale, and the forms commonly occurring as casts in the middle Miocene shales of the Coast Ranges agree with discus as here interpreted, whereas andersoni is the ancestor of the living kelp-Pecten and is more characteristic of sandy deposits than shales. Pecien cierboensis is the young of P. disc^ls, being indistinguishable from the young specimen figured by Arnold as pabloensis and from the young of living opercularis. The apical angle is apt to be smaller and the length of the shell proportionately smaller in young specimens than in old. The form brionianus helps to complete the gradation between andersoni and discus, but is probably not of significance. P. pabloensis may be no more than a degenerate offshoot of not more than varietal significance. P. dallasi may belong to this group also, being distinguished specifically by its strong radial striations and shorter dorsal ears. Any attempt to separate the middle Miocene from the upper by means of Pectens of this group is very risky and is more apt to be misleading than helpful. However, Pecien discus has never been found in the Pliocene of California and can be used with confidence to distinguish the Miocene from the Pliocene. Pecten (Aequipecten) weaveri Clark Pecien (Patinopecten) weareri Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 454, pi. 45, figs. 1, 2, 1915. Pecten tolmani Hall and Ambrose, Nautilus, Vol. 30, p. 82, 1916; Trask, Univ. Calif. Publ. Geol., Vol. 13, pp. 142, 146, pi. 3, figs. 1, 2, 1922. Shell somewhat similar to that of P. discus, but usually humped up and distorted, its altitude relatively lower and its 15 to 17 ribs broad, low, and irregular. Dimensions: Altitude, 67 mm.; longitude, 71 mm.; length of hinge, about 33 mm.; convexity of right valve, 13 mm. Type specimens: Of weaveri, at the University of California; of tolmani, No. 23 in the type collection at Stanford University. 202 San Diego Society or Natural History [Memoirs Type localities: Of weaveri, lower San Pablo formation, near San Pablo Bay, middle California; of tolmani, Briones formation, lower San Pablo group, middle California. U. Miocene: Type localities. This species is closely related to P. discus and to P. andersoni, being more nearly like the former in size and the latter in number of ribs. It is possible that all these forms inter- grade so that it is not worth while to separate them. P. weaveri is a pathologic or brackish water variation of the group, analagous in form and origin to P. bellus var. slevini Dall and Ochsner. Its chief characteristic is its broad curving ribs and noticeably concave anterior margins (the sides or submargins as usually called). Section Leptopecten Verrill, 1897 Leptopeclen Verrill, Trans. Coiin. Acad. Sci., Vol. 10, p. 69, 1897. Type (by original designation), Pecten monotimeris Conrad. Shell thin, small, of low convexity, approximately equivalved (except for the ears) ; sculptured typically with only a few low, broad folds, but on the older species and on the typical variety of P. latiauralus Conrad, where the relation to typical Aequipecten is more clearly shown, the folds re- vealing their true nature as more definite and more numerous ribs ; hinge line long, sometimes as long or even longer than the shell, byssal notch deep, with prominent (but delicate) pectinidial teeth. Geologic range : Miocene to Recent. Distribution: Warm and temperate latitudes of North and South America. This section has been treated in various ways by different authors. Dall did not con- sider it even of sectional significance, for he recognized the characters of monotimeris as due entirely to its kelp-inhabiting habits. Some authors have made it a subgenus and have included it in listing the names of species as "Pecten {Leptopecten)" sp., etc. It has generally been treated as if it belonged to Chlamys, whereas it seems rather to be a spe- cialized or degenerate form of Aequipecten. It is analogous to Lissopecten, and should probably not be accorded even sectional rank. Pecten andersoni must be included in it, for it is barely distinguishable from latiauralus, and yet andersoni may be only a variety of discus, wliich is very close to opercularis. Thus the retention of this section makes an artificial separation that obscures the natural facts ; and the section is retained here only because the writers do not wish to upset too radically the current usage, preferring in this case to try to explain the usage so that it will not be given too much emphasis. Pecten (Aequipecten) andersoni Arnold Plate 4, Figures 4, 5 Pecten {Plagioclenium) andersoni Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 82, pi. 20, figs. 5, 5a, 6, 7, 8, 8o, 1906. Pecten {Plagioctenivm) andersoni var. barkerianits Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 83, pi. 26, fig. 9, 1906. Pecten andersoni Arnold, Bull. 396 U. S. Geol. Survey, p. 17, pi. 7, fig. 4, Jan. 1.5, 1910; figure reprinted in Bull. 398, pi. 29, fig. 4, 1910. ? Pecten (Pecten) andersoni gonicoslvs Trask, Univ. Calif. Publ. Geol., Vol. 13, p. 149, pi. 1, fig. 5, 1922. "Pecten {Plagioctenium) colli Hertlein," Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 16, in part, not the type, pi. 4, figs. 5, 7, 1925. Pecten {Plagioclenium) diminutivus Hertlein and Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 623, 1927, name for the paratype of "colli." Shell like that of P. discus, but somewhat smaller, sculptured with only 15 to 16 moderately strong, distant, rounded ribs, ribs of the left valve more triangular, often with a small thread on top. Dimensions: Altitude, 38 mm.; length, 40 mm.; length of hinge, 23 mm.; convexity of the right valve, 5 mm.; convexity of the left, 7 mm.; Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 203 Type specimens: Of andersoni, lost (?); of barkerianus, at the California Academy of Sciences; of gonicostus, No. 12,370 at the University of California; of diminutivus, No. 127 in the type collection at Stanford University. Tijpe localities: of andersoni, lower or middle Miocene north of Santa Cruz; of bar- kerianus, middle Miocene of Barker's Ranch, Kern County; of gonicostus, upper Miocene, Briones formation, of middle California; of diminutivus, Miocene (Temblor ?) west side of Elephant Mesa, Scammons Lagoon Quadrangle, Lower California. Miocene: Lower, middle, and upper (?) of middle California; middle Miocene of Lower California (Hertlein). This species is very closely related to P. discus, in spite of the fact that it is placed in another section. It is possible that the form gonicostus should be referred to P. discus instead of to andersoni. When small, the ribs of andersoni are higher and stronger. P. andersoni is also very closely related to the living latiauratus, and can only be distin- guished by its larger size, stronger ribs, and narrower byssal ear. P. tumbezensis is also similar, but has larger ears, the dorsal ears being longer than the ventral, and the shell heavier, though smaller. P. andersoni can hardly be used as an index of the lower Mio- cene, for it must have lived through, giving rise in the upper Miocene or Pliocene to latiauratus. Pecten (Aequipecten) latiauratus Conrad Perlen latiauralvs Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, Pt. 2, p. 238, pi. 18, fig. 9, 1837; Sowerby, The.s. Conch., Vol. 1, p. 57, in part, but not the figures, 1842. Not "Peclen latiauritus Conrad," Reeve, Conch. Icon., Vol. 8, Pecten, pi. I, fig. 5, 1852, = var. moiiolimeris Conrad. Pecten latiauritus Conrad, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 645, 1864; Kiister and Kobelt, Syst. Conch. Cab., Vol. 17, Pt. 2, Spondylus und Pecten, p. 203, pi. 54, figs. 7, 8, 1888; Cooper, 7th Ann. Rapt. Calif. St. Mineralogist, p. 257, 1888; Keep, West Coast Shells, p. 167, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 193, 1892; Keep, West American Shells, p. 40, 1904; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; Kelsey, Trans. San Diego Soc. Nat. Hist., Vol. 1, p. 46, 1907; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 254, 191S; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 564, 1922; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pt. 5, p. 148, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Peclen {Chlamys) latiauritus Conrad, Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 709, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. Ill, pi. 12, figs. 2, 2a, 1903; Prof. Paper 47 IJ. S. Geol. Survey, p. 115, pi. 46, figs. 2, 2a, 3, 3a, 1906; Bull. 309 U. S. Geol. Survey, p. 244, pi. 36, figs. 2, 3, 1907. Pecten {Chlamys) latiauritus Conrad "var. monotimeris Conrad," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 112, pi. 12, figs. 4, 4a, 1903; Prof. Paper 47 U. S. Geol. Survey, p. 131, pi. 46, figs. 4, 5, 5a, 1906. Pecten {Chlamys) latiauritus Conrad var. delosi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 130, pi. 40, figs. 9, 9a, 10, lOo, 1906, the young. Pecten {Leptopecien) latiauritus Conrad, Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 3, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 57, pi. 22, fig. 2 (Con- rad's type figure), 1924; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 418, 1926. Shell thin, about 25 mm. in altitude, about as long as high, convexity moderate, the left valve more convex than the right, dorsal extremity somewhat obliquely produced, but usually not so much so as in the variety monotimeris; ribs 12 to 16, flat topped and sometimes slightly sulcated, repre- sented on the Ulterior by somewhat angulated grooves, the sides of the ribs, the liottoms of the inter- spaces, and the ears, especially the early parts and the right ventral ear, marked by strong concentric growth lines ; hmge luie long, about as long as the shell but variable, the ears sometimes sharp pointed and extended, sometimes not, strengthened by four or five radiating riblets, which are most promi- nent on the right ventral ear; byssal notch deep, with distinct pectmidial teeth. Dimensions: Altitude, 2.5 mm.; longitude, 25 mm.; length of hinge, 21 mm. (often more); con- vexity of the left valve, 5 mm.; of the right, 3 mm.; umbonal angle, 100°. Type specimen: Of delosi, No. 32 in the type collection at Stanford University. Type localities: Of latiauratus, living, San Diego; of delosi, lower San Pedro Pleisto- cene of Deadman Island, San Pedro Harbor. 204 • San Diego Society of Natural History [ Memoirs Pliocene: Third Street tunnel, Los Angeles (Arnold). Pleistocene: Basal "Saugus" of locality 244, Sexton Canyon, Ventura Co., two specimens (U. S. G.); middle "Saugus" of locality 249, Ventura, one specimen (U. S. G.); Santa Barbara; San Pedro (Cooper); San Pedro; San Diego (Arnold); San Pedro (T. S. Oldroyd). Limng: Monterey, California, to Lower California (Dall, 1921). This species is distinguished from P. bellilamellatus Arnold by its lower, flat-topped, or somewhat rounded ribs, which are usually more numerous. In the variety monotimeris Conrad the ribs become still lower and fewer so that in some specimens they are merely rounded folds and the interspaces are not distinctly separated from the ribs by impressed lines, the hinge line is often shorter, the dorsal extremity of the shell is strongly and obliquely drawn out, and the concentric sculpture is not so distinct. The specimens attributed by Arnold, entirely erroneously, to the variety monotiineris have even stronger, higher ribs than the typical form and really belong in the series of variations closer to P. bellilamellatus. The specimens here listed from the "Saugus" formation of Ventura County are of this sort. The type specimen of variety delosi Arnold is a small specimen with unusually strong concentric lamellation; but since Pecten bellilamellatus, which is probably the precursor of this species, has similar lamellation and since the young stages of many specimens of latiauratus show strong concentric sculpture, it seems probable that variety delosi is merely a young specimen from which the lamellations have not yet been worn off. There are in the Oldroyd collection from the lower San Pedro series of San Pedro several specimens like latiauratus in every way except that the ribs are sharper. They are thus closer to bellilamellatus, but can still be distinguished by their slightly more numerous, much smaller, and lower ribs. They occur along with normal specimens of latiauratus, and it does not seem desirable within such a variable species to give every slightly different form a special name, for these forms are almost surely meaningless, except for showing relationship with bellilamellatus. Mr. E.G. Vanatta, of the Academy of Natural Sciences of Philadelphia, has informed the writers that Conrad's types of latiauratus and m,onotimeris cannot be located ; but he kindly helped us with the identifications of the true latiauratus and monotimeris, and it is reasonably certain from a comparison with Conrad's figures and descriptions and with collections that Arnold's identification of monotimeris is erroneous. Pecten (Aequipecten) latiauratus Conrad variety monotimeris Conrad Plate 4, Figures 3, 6 Peclen monolimeris Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, pt. 2, p. 233, pi. 18, fig. 10, 1837; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 645, 1864; Kuster and Kobelt, Syst. Conch. Cab., Vol. 17, Pt. 2, Spondylus und Pecten, No. 257, p. 276, pi. 72, figs. 7, 8, 1888; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 257, in part, 1888; Keep, West Coast Shells, p. 167, fig. 140, 1888, 1892. "Pecten latiauratus Conrad" Sowerby, Thes. Conch., Vol. 1, p. 57, pi. 12, figs. 20, 21, 1842; Reeve, Conch. Icon., Vol. 8, Pecten, pi. 1, fig. 5, 1852. Pecten "mesotimeris" Conrad, Sowerby, Thes. Conch., Vol. 1, p. 57, 1842, probably a misspelling for monotimeris as indicated by Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 559, 1864. Pecten tunica Philippi, Abbild. u. Beschreib. Conchyl., Vol. 1, pt. 4, p. 100, pi. 1, fig. 3, 1844, said by Philippi to have come from the Sandwich Islands, but the locality, as explained by Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 574, 645, 1864, is erroneous. Pecten (Leptopecten) monotimeris Conrad, Verrill, Trans. Conn. Acad. Sci., Vol. 10, p. 69, 1897. Pecten {Chlainys) laliauritvs variety monotimeris Conrad, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 709, 1898; not Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 112, pi. 12, figs. 4, 4a, 1903; Keep, West American Shells, p. 40, fig. 20, 1904; not Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 131, pi. 46, figs. 4, 5, 5a, 1906 (see latiauratus, s. s.). Pecten (Chlamys) latiauritus variety /«cicoh/s Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 710, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 131, pi. 46, figs. 8, 8a, 1906. Volume 1 1 PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 205 Peclen (Chlaynys) laliaurUus Conrad vaxwiy fragilis Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 112, pi. 12, fig. 8, 1903, not Pedenfragilis Jeffreys, Ann. and Mag. Nat. Hist., Ser. 4, Vol. 18, p. 424, 1876. Peclen (Chlamys) latiaurilus Conrad variety cerritensis Arnold, new name for fragilis, Prof. Paper 47 U. S. Geol. Survey, p. 129, pi. 46, figs. 6, 7, 1906. Pecten (Leptopecten) latiauritus ynonolimeris Conrad, Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 57, pi. 40, figs. 1, 2, (these figures are not reproductions of Conrad's type figure as stated, but photographs of specimens at Stanford), 1924. Peclen (Leplopeclcn) laliaurUus fucicolus Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 58, 1924. Shell thin, about 30 mm. in altitude, about as long as high; convexity moderate, the left valve more convex than the right ; dorsal extremity strongly produced obliquely, excess of dorsal half-length over the ventral half-length averaging about 35 per cent but very variable (compare P. gibhus var. drcularis) ; hmge Ime long, variable, but usually not so long as the shell; ears shaped and marked like those of the typical variety, the byssal notch and the ctenolium (pectinidial teeth) also similar to those of the typical variety; ribs 7 to 13, low and rounded like folds, often not marked off from the interspaces by distinct lines, the mternal grooves of similar character, not angulated; concentric sculpture weaker than in the typical variety, but fine radial striation sometimes visible. Dimensions : Similar to those of the typical variety, though somewhat larger, as 25 :30. Type specimens: Of cerritensis, No. 162,523 in the U. S. National Museum; of fucicolus, also in the U. S. National Museum (?). Type localities: Of monotimeris, living, San Diego; of cerritensis, upper San Pedro series of San Pedro. Pleistocene: San Pedro; San Diego (Dall; Arnold). Living: Monterey, Calif., to the Gulf of California (Dall, 1921). This variety lives in great abundance attached by its byssus to kelp. Its situs ac- counts entirely for its special characters. Mrs. I. S. Oldroyd has informed the vpriters that the normal variety, although not so common, is found attached to worm tubes at low tide level near San Pedro. The forms described by Dall as fucicolus and by Arnold as cerritensis are but variations of this variety, having a smaller number of ribs. They are almost surely without significance. Intergradations of monotimeris with the typical variety are not at all rare. Pecten (Aequipecten) bellilamellatus Arnold Peclen {Chlamys) bellilamellatus Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 108, pi. 41, figs. 6, 6a, 7, 7a, 1906; Proc. U. S. Nat. Mus., Vol. 32, p. 546, pi. 50, fig. 14, 1907. Pecten. (Leptopecten) bellilamellatus Arnold, Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 418, 1926. Shell about 18 mm. in altitude, about as long as high; moderately convex, nearly equivalve; dorsal extremity only slightly obliquely produced (about as much as in P. gibhus var. drcularis) ; ribs 14 or 15, high, triangular, separated by mterspaces about as wide as the bases of the ribs so that the ribs appear widely spaced ; the whole surface of the shell sculptured by strong lamellar growth hues; hinge line long, about as long as the shell; ears sculptured with about five radiatmg riblets, dor- sal ears sharply pointed, ventral ears with an arcuate termination, the right ventral set off by a deep byssal notch which bears distinct pectinidial teeth, more strongly sculptured than the others. Dimensions: Altitude, 18 mm. ; longitude, 18 mm. ; length of hinge line, 17 mm. ; convexity of the two valves, 8 mm.; umbonal angle, 100°. Type specimen: No. 35 in the Stanford University type collection. Type locality: Pliocene, Pacific Beach, San Diego. Pliocene: Pacific Beach, San Diego (Arnold); Cedros Island, etc., Lower California (Jordan and Hertlein). ? Living: As tumbezensis. This species is distinguished from P. latiauratus Conrad by its slightly smaller size perhaps, but principally by its high, sharply-topped ribs. P. paucicostatus Carpenter has fewer ribs and the tops are more broadly rounded. 206 San Diego Society of Natural History [Memoirs Pecten (Aequipecten) tumbezensis d'Orbigny "Pecten aspersxis Lamarck," Sowerby, Proc. Zool. Soc. London, p. 110, 1835; Thes. Conch,, Vol. 1, p. 51, pi. 19, figs. 198, 199, 1842. Pecten himbezensis d'Orbigny, Voy. Amer. M6r., p. 663, 1847; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 256, 1909. Pecten sowerbyi Reeve, Conch. Icon., Vol. 8, Pecltn, pi. 1, species 4, 1852, new name for aspersus Sowerby; not Pecten soverbyi Guilding, 1826. Pecten paiicicostatus Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 645, 1864; Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 179, 1865. reprinted in Smithsonian Misc. Coll., No. 252, pp. 100, 131, 281 (bottom pagination), 1872; Kuster and Kobelt in Martini-Chemnitz Syst. Conch. Cab., Vol. 17, Pt. 2, Spondylus und Pecten, p. 281, 1888. "Pecten (Aequipecten) palmeri Dall," Arnold, Prof. Paper 47 V . S. Geol. Sur\'ey, p. 136 in part, pi. 50, figs. 2, 2a, only, 1906. Pecten (Plagioctemum) pmicicostatus Carpenter, Arnold, Prof. Paper 47 U. S. Geol. Survej', p. 137, pi. 39, figs. 3, 3a, 4, 1906. .? Pecten (Chlamys) ? tumbezensis Orbigny, Dall, Bull. 112 V. S. Nat. Mus., p. 19, 1921. Shell rather small, heav>', with 13-14 strong ribs, on the right valve rounded and clearly marked off from the interspaces, on the left valve like sharp folds, not marked off; ears large, the dorsal ears larger than the ventral. Dimensions: Altitude, 35 mm.; length, 37 mm.; hinge line, 25 mm.; convexity of the two valves, 13 mm. Type specimen: Of paucicostatus, No. 15,6346 in the U. S. National Museum. Type localities: Of tumbezensis, living, Tumbez, Peru; of paucicostatus, Gulf of Cali- fornia {fide Arnold, the locality originally given being erroneous). hiving: Gulf of California to Peru; ? Santa Barbara, California. This species is distinguished from latiauratus and andersoni by its heavier shell and stronger ribs. It is distinguished from prcevalidus by its lack of radial striations. Young specimens look like P. bellilamellatus. Pecten (Aequipecten) praevalidus Jordan and Hertlein Pecten {Leptopecten) prsevalidus Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 435, pi. 29, figs. 2, 3, 1926. Like typical Pecten latiauratus Conrad but aljout twice as large and with distinct radial striation on the ribs and interspaces; ears as in tumbezensis. Type specimen: No. 2,101 at the California Acadmey of Sciences. Upper Pliocene: S. E. of Turtle Bay, Lower California, common (Jordan and Hertlein). Section Plagioctenium Dall, 1898 Plagioctenium Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 696, 1898. Type (by original designation), Pecten ventricosus Sowerby = P. gibbus variety cir- cularis Sowerby. Shell like that of Aequipecten, s. s., but usually with stronger, squarer ribs, on which the radial striations are faint or obsolete; valves often more convex; hinge Ime long, ears nearly equal. Geologic range: Oligocene to Recent; in California, upper Miocene or lower Pliocene to Recent. Distribution: Practically world wide in warm and temperate waters. Pecten purpuratus and Pecten gibbus variety irradians each show the intergradation between Plagioctenium and the typical section of Aequipecten, and they show that the characters of the section are hardly more than of specific significance. Pecten purpuratus Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 207 variety hakei grows large and ponderous, so that it might be mistaken for a Lyropecten; but it can be recognized as a member of this group not only by its intergradation with typical purptiratus but also by the fact that, its ponderosity being newly acquired, the shell did not have time to develop grooves on the interior of the hinge as had the con- temporaneous Lyropectens. The species of the subgenus Aequipecten, and especially the Aequipectens belonging to this section, are among the most variable species known. The end forms of such variable species as Pecten gibbus Linnaeus appear so different that they have been described as distinct, although later, more careful work has shown every gradation between them. Dall (1898) gave a very reasonable treatment of the variations of Pecten gibbus, recog- nizing the geographic extremes as varieties only. Our Pacific coast forms must be treated in the same way, if we wish to avoid the danger of obscuring, for the sake of characters due mainly to the local configuration of the coast line or to local variations in climate, their true relationships and their value for purposes of correlation. A large series of Pacific coast Plagiocteniums shows intergradations between most of the forms that have been described as if they were distinct species. They are here arranged into groups somewhat as in Ball's arrangement of the Atlantic forms. Pecten (Aequipecten) evermanni Jordan and Hertlein Pecten (Plagioctenivm) evermamii Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 439, pi. 27, fig. 1, 1926. Dimensions: Altitude, 115 mm.; length, 125 mm.; umbonal angle, 108°. Type specimen: No. 210 at the California Academy of Sciences. Pliocene: Cedros Isiland, Lower California, upper Pliocene (Jordan and Hertlein). This species is closely related to Pecten purpuraius variety hakei Hertlein, but it ap- pears to be distinct. It is distinguished by its large number (30-31) of flat-topped, very broad ribs, with very narrow interspaces. The convexity of the valves is moderate. Pecten (Aequipecten) purpuratus Lamarck Plate 4, Figures 2a, 2b, 2c Pecten -purpuratus Lamarck, Hist. Anim. s. Vert., Vol. 6, pt. 1, p. 166, 1819; Desh. and M. Edw. Ed., Vol. 7, p. 134, 1836; Sowerby, Thes. Conch., Vol. 1, p. 52, pi. 15, fig. 113, pi. 16, figs. 123-125, 1842; Reeve, Conch. Icon., Pecten, pi. 5, species 25, 1852; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 149, pi. 26, figs. 5, 6, 1910; Peile in Bosworth, Geol. and Paleo. of N. W. Peru, p. 178, pi. 25, fig. 9, 1922 (MacMillan & Co., London). Pecten (Plagiocteniuni) purpuratus Lamarck, Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 14, pi. 1, fig. 1, pi. 4, figs. 2, 4, 1925; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 442, 1926. Shell of moderate to large size, usually of low convexity, with the left valve always the more convex, outlme circular or with slight obliquity, with a comparatively large apical angle, weight of shell variable among the different varieties, sculpture consistmg of 19 to 26 radiating ribs, the height and angularity of which varj- roughly with the weight of the shell ; hinge line more than half the length of shell, byssal ear with about five fairlj' strong radiating riblets, the other ears with seven or eight finer riblets, dorsal ears nearly square on the end, the left ventral ear gently arcuate, the right ventral strongly arcuate with a fairly deep byssal notch, the whole surface of the valves including the ears covered with fine growth-line lamehse which are sometimes prominent as fringes along the sides of the ribs. Dimensions: Altitude, 105 mm.; longitude, 120 mm.; length of hinge, 70 mm.; convexity of the two valves, 40 mm., of which about 27 mm. are in the left valve; umbonal angle, 118° . Pecten purpuratus represents a very variable group of forms, some of the varieties of which bear a striking resemblance to corresponding variations of Pecten eboreus Conrad of the Atlantic coast. The group as a whole in practically all cases is distinguishable from 208 San Diego Society of Natural History [Memoirs Pecten gibbus and its varieties by the much lower convexity of the valves, by the fact that the left valve instead of the right is always the more convex, by a greater average number of ribs, and by the greater size of the adult in all cases except in variety mendenhalli, which is quite possibly the young of one or more of the others. The varieties of Pecten deserti are intermediate forms with nearly equal convexity of valves, a smaller size and a smaller average number of ribs than purpuratus, and (except in the distorted type variety deserti) with a greater ratio of altitude to length. The variations of the different characters may be summarized as follows: The umbonal angle, though not at all constant within the varieties themselves, is noticed to be slightly larger in varieties percanis, purpuratus, and hakei than in varieties mendenhalli, cristobalensis, callidus, or subdolus. The extremes are percarus and subdolus, but there are specimens of percarus which have as small an angle as the type of subdolus. The dorsal extremities of varieties percarus and subdolus, and to a less extent those of callidus and cristobalensis, show a strong tendency to be drawn out obliquely, whereas in the other variaties the valves are less inequilateral. The ribs of the right valve vary from the broad, moderately high ribs on typical purpuratus to high, narrow, squarish ribs on ex- treme specimens of cristobalensis, and to low rounded ones on percarus and subdolus. The ribs of typical purpuratus and also of variety cristobalensis appear in the living specimens abnormally wide because of the lateral fringes (see the quotation from Dall on the varieties of Pecten gibbus) ; so that in comparing them with fossils on which the fringes have been worn off, allowance must be made for the difference. The shell of typical purpuratus is moderately thick, that of variety hakei is thicker, that of percarus and subdolus thinner. The convexity of percarus is slightly less than that of other varieties, though the convexity of each variety varies considerably. The relative length of hinge line is slightly less in the type specimens of subdolus, callidus, and percarus, and in some specimens of mendenhalli. Also, in varieties subdolus, callidus, and sometimes mendenhalli, the ratio of altitude to length is greater than in the other forms, though this character is rather a function of the umbonal angle than a distinct feature. The ears vary in the number and strength of striations, though preserving on the whole a similar general appearance. Thus there is represented within this species a long list of variable characters, to which others probably could be added. The number of possible combinations of these characters is practically unlimited. With every new collection new combinations appear, forms with half the characteristics and perhaps the general appearance of one variety, but with other important characteristics of a second. There are intergradations between the extremes of all the characters; and by selecting different features as ultimate criteria, the specimens of a collection may be assigned to the different varieties in many different ways. The whole group cannot be arranged satisfactorily in a linear series, but had better be thought of as a spherical aggregate with typical purpuratus (fortunately) in the center and variations outward in every direction, there being lateral intergradations as well between the various radiating series. All of the varieties so far described have been found at a single locality at Cedros Island, Lower California, and many of them have been found together in a limited horizon in the Santa Clara Valley of southern California, hundreds of miles from Cedros Island. Typical purpuratus and variety cristobalensis are found living off the coast of Peru today, and the latter is labeled in the Oldroyd Collection at Stanford University, "color form." It may be only a question of time before others of the group are found living in southern waters. With these records under consideration and with a reali- zation of the great variability generally exhibited by other strong or dominant species, it seems as if it would greatly obscure the scientific facts of the case and lessen the value of Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 209 this common group for purposes of correlation to separate the variations artificially into distinct species. The names already proposed are here retained as varieties of the earliest described form, which happens to represent very nearly the average of their properties; for it is not thought desirable to destroy whatever possible value, if any, may later be found in such separations, and in general practice not much stress is laid upon the im- portance of varietal distinctions. There are in the collections several forms which do not agree closely with any of the previously described varieties, and might, as Davenport says of his Cold Spring Harbor form-unit of Pecten gibbus, "receive a new varietal name, were not the futility of this endless naming, alas, too evident." Variety purpura tus, s. s. Pliocene: Lower California (Hertlein; Jordan and Hertlein); Pico formation near the Los Angeles Reservoir, San Fernando, one specimen (Stanford collection). Pleislocenc: Tablazos beds of N. W. Peru (Peile). Living: Coqiiimbo, Chile, northward to Ecuador (Dall, 1910). The typical variety is distinguished by its large umbonal angle, moderate thickness of shell, moderate convexity, comparatively wide but only moderately high ribs with con- spicuous lateral fringes, length greater than altitude, hinge line more than half the length of the valves, and obliquity scarcely noticeable. The ribs of the right valve are equal to or a Uttle wider than the interspaces ; those of the left valve are narrower than the inter- spaces. Ribs 22 to 25. Pecten (Aequipecten) purpura tus Lamarck variety hakei Hertlein Plate 8, Figure 3 Peden (Plagiocicnium) hakei Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 18, pi. 4, figs. 1, 3, 192.5. Dimensions: Altitude, US mm.; longitude, L35 mm.; length of hinge, 90 mm.; convexity of two valves, 57 mm.; inubonal angle, 110-120°. Type specimen: No. 40 in the type collection at Stanford University. Type locality: Pliocene of Turtle Bay, Lower California. Pliocene: Lower California (Hertlein); San Diego formation, San Diego (Hertlein and Grant); lyi miles west of Somis, Ventura Co., "Saugus" formation (Stanford collection). This variety is characterized by a larger, heavier, thicker shell than the typical form, and the ribs are somewhat more rounded and less definite. The convexity of the valves varies greatly. This variety bears all the ear-marks of a gerontic type which in old age thickened its shell and deposited material less regularly and less delicately than it did in its young and mature stages. The opinion that hakei is the gerontic stage of variety purpuratus or cristobalerisis is strengthened by the fact that the older specimens of these two varieties grade perfectly into the smaller specimens of hakei, and also by the fact that there are no young specimens of hakei in the collection. If similar gerontic forms should be found living, the name had better be discarded ; but the name is retained here in case larger collections should show that no living individuals grow so large, for the size might then have some significance. In the latter case some of the Pliocene records from Lower California of either purpuratus or cristobalensis or both should be included under this variety. Ribs 22 to 26. 210 San Diego Society of Natural History [Memoibs Pecten (Aequipecten) purpuratus Lamarck variety cristobalensis Hertlein Plate 5, Figure 2 Pecten (Plagiodenium) cristobalensis Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 19, pi. 3, figs. 1, 2, 5, 1925; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 439, 1926. Dimersions: Altitude, 85 mm.; length, 90 mm.; length of hinge, 52 mm.; convexity of the two valves, 35 mm. Type specimen: No. 36 in the type collection at Stanford University, herewith figured. Type locality: Uppermost beds, slopes of Salada, S. E. of Turtle Bay, San Cristobal Bay Quadrangle, Lower California. Pliocene: Lower California (Hertlein; Jordan and Hertlein); locality 217b, middle Pico of Holser Canyon, Los Angeles Co., one specimen doubtfully referred to this variety (H. R. G.), similarly, locality 217a, two specimens (H. R. G.), locality 214, middle Pico west of Fernando Pass, Los Angeles Co., one specimen very doubtful (H. R. G.). Living: Coast of Peru (Oldroyd collection). This variety is characterized by stronger sculpture ; the ribs are narrower and higher and of sharper outline than on the typical variety. Without the fringes the ribs are nar- rower than the interspaces even on the right valve. The type specimen itself, however has more rounded ribs, looking much as a young hakei should look. The "color form" in the Oldroyd Collection at Stanford University is pinkish in color, whereas the typical form is more often purple. Ribs 20 to 24. Pecten (Aequipecten) purpuratus Lamarck variety percarus Hertlein Peclen (Acqmpecte7i) perconts Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 13, pi. 2, figs. 2, 5, 1925; Jordan and Hertlein, Vol. 15, p. 435, 1926. Dimensions: Altitude, 81 mm.; longitude, 90 mm.; length of hmge, 48 mm.; convexity of the two valves, 24 mm.; umbonal angle, 121°. Type specimen: No. 42 in the type collection at Stanford University. The "holotype" of percarus does not consist of matched valves, for the right has 20 ribs and the left 25. Therefore the two valves should be called cotypes. Type locality: Mouth of big arroyo N. W. of Elephant Mesa, Scammons Lagoon, Lower California. Pliocene: Lower California (Hertlein; Jordan and Hertlein); middle Pico of locality 214, one specimen, and of locality 211, three specimens, west of Fernando Pass, Los Angeles Co., (H. R. G.); ? Pliocene of the Waccamaw beds, South Carolina, as sencscens (Dall), (if the two forms should be the same, this name of course has priority). This variety is distinguished by its low, rounded ribs, thinner shell, low convexity, large umbonal angle, and (in the type) short hinge line. In some respects this variety is the most definite of all, although there are intergrades with the less characteristic speci- mens of cristobalensis, and there is some question about the advisability of trying to sepa- rate it from the variety subdolus. It usually (but not always) has a larger umbonal angle than subdolus, and the ratio of altitude to length is smaller. Sometimes also the hinge line is longer than is normal for subdolus. So far as can be told from the figure and description, this variety is indistinguishable from Pecten eboreus Conrad variety seiiescens Dall (Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 751, pi. 29, fig. 5, 1898); but no specimens have been available for comparison. Ribs 20 to 25. VoLtTMEl] Pliocene and Pleistocene Mollusca of California 211 Pecten (Aequipecten) purpuratus Lamarck variety subdolus Hertlein Plate 5, Figure 1 "Pecten [Plagioclenmm) cerrosensis Gabb," Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 123, pi. 49, figs. 1, la, lb, 1906, in part; BuU. 309 U. S. Geol. Survey, p. 24, pi. 35, fig. 6, 1907, in part. Pecten {Plagioctenivm) subdolus Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 20, pi. 5, figs. 2, 4, 7, 1925; Jordan and Hertlein, Vol. 15, p. 443, 1926. Dimensions (of large specimen): Altitude, 110 mm.; longitude, 110 mm.; length of hinge, 65 nam.; convexity of the two valves, 30 mm.; mnbonal angle, 105°. Dimensions of the type: Altitude, 49 mm.; longitude, 50 mm.; length of hinge, 21 mm.; convexity, 18 mm.; umbonal angle, 108°. Arnold records a specimen 200 mm. long. A specimen from San Diego had an umbonal angle of only 100°. Type specimen: No. 51 in the type collection at Stanford University. Type locality: Pliocene of Pacific Beach, San Diego. Pliocene: Cedros Island, Lower California (Arnold); Cedros Island and Turtle Bay, Lower California (Hert- lein; Jordan and Hertlein); San Diego (Hertlein; Jordan and Hertlein; Hertlein and Grant); middle Pico of locality 211, west of Fernando Pass, Los Angeles County, two specimens (H. R. G.); also locality 214, one specimen which might equally well have been referred to callidus (H. R. G.). This variety is distinguished by low, rounded ribs with wide interspaces, and by short hinge line and small umbonal angle. Consequently, the ratio of altitude to length is larger, being usually nearly one to one. This variety is very like percarus in sculpture and callidus in shape. Ribs 20 to 22. Arnold listed Pecten {Plagiocienium) subventricosus Dall as a synonym of this form, and if he were correct Dall's name should of course be used. However, Mr. Mansfield of the U. S. National Museum has informed the writers that Ball's type is close to Pecten gibbus var. circularis Sowerby. Pecten (Aequipecten) purpuratus Lamarck variet.y callidus Hertlein Plate 5, Figure 4 "Pecten {Plagioctenium) cerrosensis Gabb, square ribbed variety," Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 124, 19C6. Pecten {Plagiocienium) callidus Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 22, pi. 5, figs. 1, 3, 5, 6, 1925; Jordan nnd Hertlein, Vol. 15, p. 437, 1926. Dimensions: Altitude, 54 mm. ; longitude, 55 mm. ; length of hinge, 29 mm. ; convexity of the two valves, 19 mm.; umbonal angle, 107°. Type specimen: No. 53 in the type collection at Stanford University. Type locality: Pliocene of Cedros Island, Lower California. Pliocene: Lower California (Hertlein; Jordan and Hertlein); San Fernando (Arnold); San Diego (Stanford collection); middle Pico of locality 211, one specimen, of 212, one, of 213, two, and of 214, six, all west of Fernando Pass, Los Angeles Co. A few of these specimens are typical, but most of them are intermediate between this and other varieties. This variety is characterized by high, moderately wide, square ribs, like those of cristobalensis but not so extreme. The hinge line is shorter and the umbonal angle smaller than in cristobalensis, and the ratio of altitude to length is about one. Arnold records a specimen over 100 mm. in altitude, but usually callid^ls is smaller than the other varieties (with the excei^tion of mendenhalli) . It is like subdolus with stronger sculpture. Ribs about 20. 212 San Diego Society of Natural History [ Memoirs Pecten (Aequipecten) purpuratus Lamarck variety mendenhalli Arnold Pecten (Plagioctenium) cerrosensis Gabb variety mendenhalli Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 8-1, pi. 25, figs. 2, 2a, 2b, 1906. Not "Pecten {Plagioctenium) cerrosensis mendenhalli Arnold," Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 16, pi. 1, fig. 5, 192.5 ( = Pecten gibbus var. demiurgus Dall ?). Pecten mendenhalli Arnold, Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 473, pi. 25, figs. 4, 5, 1926. Not "Pecten (Plagioctenium) mendenhalli Arnold" Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 442, 1926, but the authors in this reference show why mendenhalli is not a variety of cerrosensis Gabb. Dimensions: Altitude, 40 mm.; longitude, 44 mm. (or proportionally less in some specimens); length of hinge, 29 mm. (or less) ; convexity of the two valves, 16 mm. ; umbonal angle, 110° (or 105°). Type specimen: No. 164,849 in the U. S. National Museum. Type locality : Pliocene of Santa Rosalia, Lower California. Pliocene: Santa Rosalia, Lower California; Garnet and Alverson canyons just north of the Mexican boundary, San Diego Co., Calif. (Arnold); Coyote Mt., Imperial Co., Calif. (Hanna); Cedros Island, Lower Calif. (Hertlein, oral communication); middle Pico of locality 214, west of Fernando Pass, Los Angeles County, three specimens with rounded ribs and prominent lamellation, probably belonging here (H. R. G.). This variety is characterized bj^ rather wide but low, squarish or rounded ribs and small size. The hinge line and apical angle vary considerably. More careful work may show that this form is just the young of typical purpuratus or of one of the later named varieties. It is difficult to distinguish from any of them. Ribs 19 or 20. Pecten (Aequipecten) deserti Conrad Plate 5, Figure 3 Pecten deserti Conrad, "Descr. Fos. and Rec. Shells," U. S. House of Representatives Doc. 129, p. 15, July, 1855; U. S. Pacific Railroad Survey Reports, Vol. 5, p. 325, pi. 5, fig. 41, 1856; Conrad's descriptions reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, pp. 167, 181, 1909; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 257, 1888; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 232, pi. 6, figs. 1, la, 16, 1917; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 470, pi. 25, figs. 1, 2, 3, 1926. Pecten (Plagioctenium) deserti Conrad, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 703, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 85, pi. 26, figs. 1, 2, 2a, 3, 4, 4a, 1906. Shell of small or moderate size, noticeably higher than wide and of low convexity except in the distorted type variety, valves almost equally convex; ribs small, low, and romaded, or high, wide, and square, varying in number from 15 to 19. The group of forms included here is intermediate between the Pecten purpuratus group and the Pecten gibbus group. It probably represents a derivative or a branch of the purpuratus stock which was able to adapt itself to more rigorous living conditions, for it is found farther northward and in the probably slightly brackish water deposits at the head of the Pliocene Gulf of California and in the San Joaquin basin. It is unfortunate that the earliest described member of this group is the distorted, probably brackish water variety from the Coyote Mt. region; for although it is not typical, it must be called the type variety. The normal marine form is described as invalidus Hanna (new name for cooperi Arnold), and except for the rules of nomenclature invalidus should be the species name and deserti the specialized variety. The Pecten gibbus stock including the common Pacific coast variety circularis probably represents a later wave of migration from a com- mon center or metropolis. The deserti group, however, is more closely linked by inter- grading series with Pecten purpuratus, and it is possible that the two should be classed together as has been done apparently with the Atlantic coast varieties of Pecten eboreus Conrad, which seem to include representatives of both. Hanna says in reference to three forms typical of these three groups: "The species circularis, deserti, and mendenhalli Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 213 are undoubtedly very closely related. With a large series of specimens from different places, it is possible all would be found to constitute an intergrading series, but at present some of the connecting links seem to be absent." It is true that we have now the inter- gradation between viendenhalli and deserti, and in other parts of this hemisphere there are similar intergradations between the deserti type and the circularis or gibbus type. Never- theless, the three groups appear to have a distributional and perhaps a stratigraphic significance; and in any case, Pecten purpuratus, a clearly characterized species close to the typical Aequipectens, should be specifically separated from Pecten gibbus, of which the variety circularis is the type of Ball's section Plagioctenium. Pecten deserti and its varieties are distinguished from Pecten purpuratus by the equal convexity of the valves, the fewer ribs, the greater ratio of altitude to length, the smaller size, etc. From Pecten gibbus and its varieties they are distinguished by the equal and normally lower convexity of the valves, and in some cases by the fewer ribs. Variety deserti, s. s. Dimensions: Altitude, 32 mm.; longitude, 32 mm.; length of hinge, 22 mm.; convexity of the two valves, 25 mm. ; umbonal angle varying from 90° to 105°. Sometimes the longitude is 4 or 5 mm. greater or less than the altitude. Type specimen: No. 8398 in the U. S. National Museum. Pliocene: Coyote Mt., Imperial Co. (Conrad; Arnold; Hanna; etc.). The specimens of this variety nearly all have a somewhat distorted appearance. The young specimens are very convex, but most of them when about half grown flatten out noticeably, giving the whole a fanciful resemblance to the ruffled-up neck of a pigeon. A few less distorted specimens, however, show the relationship of this variety to the more normal, moderately convex varieties. Pecten eldridgei Arnold, from the Pliocene of the southern San Joaquin basin, is a distorted, specialized, probably also brackish water form even more pecuUar than deserti. It is characterized by a small, very thick shell that is so buckled up that the two valves when put together are almost spherical or nut-like in shape. This variety is abnormally convex for the species. It is distinguished by the con- vexity, by the close-set, fairly small ribs of the right valve which are roughly rounded, with narrow flattened tops, by the roughly triangular ribs of the left valve, and by the distorted appearance. The outline is very inconstant, the shell being elongated some- times in the direction parallel to, sometimes in the direction perpendicular to the hinge. Ribs usually 18 or 19. Pecten ( Aequipecten) deserti Conrad variety invalidus Hanna Plate 5, Figures 5a, 5b, 5c, 6a, 66, 6c Pecteyi (Plagioctenium) cooperi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 124, pi. 49, figs. 2, 3, 4, 1906, not Pecten coo-peri E. A. Smith, Fauna and Geography of the Maldive and Laccadive Archipelagos, Vol. 2, p. 621, 1903. Pecten invalidus Hanna, new name for Pecten cooperi Arnold, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 177 top, 1924. Pecten {Plagioctenium) invalidus Hanna, Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 441, 1926, in part (?). Dimensions of tj^pe: Altitude, 35 mm.; longitude, 37 mm.; length of hinge, 22 mm.; convexity of the two valves, 16 mm. ; umbonal angle, 105°. Dimensions of figured specimen (plate 5, figures 5) : Altitude, 40 mm. ; longitude, 39 mm. ; length of hinge, 26 mm. ; convexity of the two valves, 18 mm. ; umbonal angle, 95°. 214 San Diego Society or Natural History [Memoirs Type specimen: No. 8 in the Stanford University type collection. Type locality: Pliocene of Pacific Beach, San Diego. Pliocene: Pacific Beach, San Diego (Arnold; Hertlein and Grant); middle Pico of locality 211, one specimen, of 213, two, of 214, two, west of Fernando Pass, Los Angeles Co. (H. R. G.) ; middle Pico of locality 217, six specimens, of 217a, fourteen, of 217b, six, Holser Canyon, Los Angeles Co. (H. R. G.), This variety is distinguished by its moderate convexity, square, high ribs, which are sometimes considerably wider than the interspaces on the right valve, small umbonal angle and consequently larger ratio of altitude to length. It is very close to specimens of Pecten eboreus Conrad var. ? in the Stanford University collection, from the PHocene Caloosahatchie marls of Florida. Ribs 16-19. Pecten (Aequipecten) deserti Conrad variety impostor Hanna Peclen deserli Conrad, Arnold, Bull. 396 U. S. Geo!. Survey, p. 76, pi. 26, figs. 3, 4, Jan. 15, 1910, reprinted in Bull. 398, pi. 48, figs. 3, 4, 1910. Pecten yrolevs Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 232, pi. 6, figs. 2, 2a, 2b, 2c, 1917, not Pecten proteus Sower- by, Thes. Conch, p. 59, pi. 13, figs. 53, 54, 1847. Pecten impostor Hanna, new name for Pecten proteus Nomland, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 177 middle, 1924. Dimensions: Altitude, 44 mm.; longitude, 42 mm.; length of hinge, 25 mm.; convexity, 18 mm.; umbonal angle, 90-95°. Type specimen: No. 11,089 at the University of California. Type locality: Pecten coalingensis zone, Etchegoin middle Pliocene of the Coalinga district, middle California (Nomland). Pliocene: Type locality; middle Pico of locality 211, three specimens, of locality 214, five, west of Fernando Pass, Los Angeles Co. (H. R. G.); middle Pico of locality 217, three, of 217a, seven, of 2176, five, Holser Canyon, Los Angeles Co. (H. R. G.). This variety is characterized by low convexity, low, roughly rounded ribs, with a very variable outline. Often the umboilal angle is unusually small and likewise the ratio of altitude to length. Some of the shells are conspicuously oblique. Ribs 18 to 20. Pecten (Aequipecten) eldridgei Arnold Pecten {Plagioctenium) eldridgei Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 87, pi. 25, figs. 3, 3a, 36, 4, 4a, 5, 5a, 6, 1906. Pecten eldridgei Arnold, Pack, Prof. Paper 116 U. S. Geol. Survey, p. 35, 1920. Shell small, both valves very convex, thickened, sculptured with 19 to 20 low, squarish ribs. Dimensions (from Arnold): Altitude, 20 mm.; longitude, 21 mm.; length of hinge, 15 mm.; diameter of the two valves, 15 mm. Type specimen: In the U. S. National Museum, No. 164,850. Type locality: In the hills south of Dabney water wells, McKittrick district, Kern County, "upper Miocene." Pliocene: Etchegoin formation of the southeastern end of the San Joaquin basin, at the type locality (Arnold), and between McKittrick and Midway (Pack). The original reference of this species to the Miocene created an enigma, for the species from which it is most likely to have been derived, deserti and circularis, are not known so far north as California in the Miocene. Pack, however, has identified it in Etchegoin beds not far from the type locality; and it is probable that the type locality also is Etchegoin. P. eldridgei appears to be a stunted, brackish-water derivative of Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 215 deserti, most like the typical form; and it is not at all surprising to find it in beds that are approximately equivalent in age to the beds in which the varieties of deserti are found. Even the typical variety of deserti, from the Imperial formation, may be of approximately equivalent age. Pecten (Aequipecten) gibbus (Linnseus) Ostrea gibba Lianaeus, Syst. Nat., Ed. 10, p. 698, 1758; ? Born, Test. Vindo., p. 107, 1780. Pecten dislocatus Say, Journ. Acad. Nat. Sci., Phila., Vol. 2, p. 260, 1822; American Conchologist, pi. 56, figs. 2, 2a, 1834; Holmes, Post-Pliocene Fos. of So. Carolina, p. 13, pi. 2, fig. 13, 1858. Pecten soverbii GuUding, 1826 (not of Reeve 1852). "Pecten purpuralus Lamarck" Conrad, Amer. Marine Conch., p. 10, pi. 2, fig. 1, 1831; DeKay, Zool., N. Y., Vol. 5, p. 174, 1843. Pecten gibbus Linnaeus, Sowerby, Thes. Conch., Vol. 1, fig. 17 (only), 1843; d'Orbigny, Moll. Cuba, Vol. 2, p. 352, 1845; Reeve, Conch. Icon., Pecten, pi. 9, figs. 376, 37c, not 37a, 1852; I\jebs, West Indies Mar. Sh,, p. 134, 1864; Arango, Fauna Mai. Cubana, Vol. 2, p. 270, 1878; Davenport, Mark Anniversary Volume, pp. 123-136, pi. 9, 1903. "Pecten circularis Sowerby," Guppy, Paria Fauna, p. 155, 1877. "Pecten nucleus Born," Heilprin, Trans. Wagner Inst. Sci., Phila., Vol. 1, p. 102, 1886. Pecten irradians var. dislocatus Say, DaU, Bull. 37 U. S. Nat. Mus., p. 34, 1889. Pecten (Plagioctenium) gibbus Linnaeus, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 745, 1898; Maury, BuUs. Amer. Paleontology, No. 34, p. 27, 1920; No. 42, p. 86, pi. 14, fig. 2, pi. 16, fig. 1, 1925. Pecten (Plagioctenium) gibbus var. dislocatus Say, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 746, 1898. The group of closely related intergrading forms here classified under the name of Pecten gibbus is characterized by shells of moderate size and thickness, usually of strong convexity, the right valve noticeably more convex than the left, the outline nearly circular but with the dorsal margins more or less obliquely drawn out ; sculptured by ribs averag- ing for the whole group 19 or 20 in number, with moderate height and often a tendency to be flattened on top, equal to or wider than the interspaces; hinge line more than half as long as the shell; ears sculptured by radiating lines of varying strength, four to six fairly strong ridges on the right ventral ear, on the other ears a varying number of finer lines which sometimes cover only the inner part of the ear, sometimes spread over the whole ear, and in a few specimens of nearly every variety continue up over the normally smooth areas between the ears and the first rib on the main part of the valve ; byssal notch fairly sharp and deep ; the whole surface including the ears, but especially the spaces between the ribs, covered with fine concentric lines of growth. Dall says, in speaking of the group as a whole (p. 748), "The variations in the fossils parallel those of the living forms; the concentric sculpture may be weaker or stronger, may be visible on the backs of the ribs or only in the interspaces. The ribs may be more or less emphatic, rounded or flat-topped with lateral angles. In the latter case the con- centric sculpture sometimes stops short at the angle, leaving the unworn back of the rib smooth, as if the concentric lamellae had been worn off. In this case, which is the most conspicuous of the various mutations, the ribs appear laterally fringed. All the species of this group, recent or fossil, show this mutation occasionally, though it is rarer among the recent shells than among the fossils." There is great hesitancy on the part of conchologists and even of paleontologists to recognize the specific identity of related forms which are found on the two sides of the continent, even though the morphologic characters of these forms fall within the limits of specific variation. This feeling has really had a detrimental effect on the science, for it has obscured the true relations of the forms and spread the conception that the California province is entirely separate and impossible to correlate with other regions. There are a number of species on the Atlantic coast which are so close to our Pacific coast forms that 216 San Diego Society of Natural History [ Memoirs if the two occurred together it would be impossible to distinguish them. If, in addition, it can be shown that the two forms belong to a common stock that has migrated from one coast to the other during the middle or late Tertiary or the Quaternary, the two should be classed under the same name. In such a case it is of considerable value to know that the two are the same, in addition to eliminating a superfluous name and diagnosis from the mass of material that each paleontologist must learn; and there is nothing at all to be gained by separating forms that it is reasonably certain are identical. The argument that the purely geographic separation of species enables a worker to tell from the name what region a specimen came from is absurd, for it is much easier and more likely to be intelligible to everyone to say such and such a species from such and such a locality than it is to give each geographic race a separate name when there are no distinguishing char- acters. An example of such a case is given by Davenport {loc. cit., 1903), in his tabulation and analysis of the characters of a very large series of the living varieties of Pecten gibbus from Tampa, Florida, and from San Diego, California. Davenport collected and measured considerably over five hundred specimens from each locality (having already studied several other large series of more northern varieties of the same species from the Atlantic). He examined the number of ribs and concluded that Tampa specimens average about one rib more per shell, but noted that the Tampa average is higher than that from any other locality which he had studied on the Atlantic coast, and that the San Diego average occupies an intermediate position. He found the convexity of the two lots not noticeably different, though the San Diego specimens are more variable. He measured the ratio between the dorsal half-length and the ventral half-length of the shells (i. e., the length of the shell behind a diameter drawn perpendicu- lar to the hinge line at the beak and the length of the shell in front of that line, or in other words the obliquity of the valve) and found that as in most Pectens the dorsal half- length exceeds the ventral in both lots. The excess is 15% in the San Diego set and only 6% in the Tampa set. Davenport notes that the obliquity is not so great in the Pacific coast variety as in other Pacific coast living species (such as Pecten latiauratus Conrad) ; and implies therefore that the greater obliquity is attributable to the influence of local environment; but it is largely on account of this difference that the San Diego form is here accorded varietal distinction. Davenport discusses also the similarity in color mark- ings, noting the positions of the characteristic light-colored ribs that are found in many specimens of both series, and showing that the correspondence of position is more than coincidental. Having demonstrated by means of the details of color markings, as well as by the similarity of general proportions, the close relationship of the two forms, he goes on to inquire into their ancestry, pointing out that Dall has recorded in the Miocene forms indistinguishable from the typical variety, and recalling the connection which is known to have existed between the two oceans at that time. Thus we have the explana- tion of the common form in the ancestry. Neither branch of the original race has changed sufficiently since the separation to become a distinct species. As Davenport has already observed, it is sometimes easier to tell the specimens from different localities along the Atlantic coast than it is to tell the Atlantic coast forms from the Pacific coast. Of the various varieties of Pecten gibbus the Pacific coast variety circularis is the closest to the typical form. The species is recorded then in its typical form from the Miocene of Virginia (Dall), from the Pliocene of Florida (Dall) and of Trinidad (Maury), from the Pleistocene of the Carolinas, Florida, and the Antilles (Dall). The variety demiurgus Dall is recorded Volume I 1 PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 217 from the Miocene of Trinidad; and two other varieties, venezuelanus and cornellanus, both of F. and H. Hodson (Bulls. Amer. Paleo. No. 49, pp. 25 and 26, with plates, 1927), are recorded from the Miocene of Venezuela and the Canal Zone. The last two authors describe still another variety from the Pliocene of the Canal Zone {caucanus, p. 27, pi. 15, figs. 1, 8); and Dall describes variety ampUcostatus from the Pliocene of Florida and lists variety borealis Say from the Pleistocene of Florida. The records of P. mendenhalli, P. circularis, and P. abietis made by Hertlein and by Jordan and Hertlein from the Pliocene of Lower California should probably be referred to variety demiurgus Dall; and the records of P. calli by the same authors from the Pliocene of Lower California and of P. circularis var. ocquisulcatus by various authors from the Pleistocene of California should be referred to the variety circularis. The species is living today from New England to Brazil and from southern California to Peru, and is also reported from the west coast of Africa. The New England variety is classified by Dall as var. borealis Say, that from the middle Atlantic states as var. irradians Lamarck, that from Cape Hatteras to Brazil and west Africa as typical gibbus, the variety inhabiting fuci as var. nucleus Bonn, an- other supposedly ecologic form as var. ampUcostatus from Texas to Cartagena, the form ranging from California to Peru as P. circularis, and the larger, less convex form from California and Lower California as var. cequisulcatus of circularis. Thus it is seen that the species has, and has had in the past, a very wide distribution. The metropolis of the species appears to have been in the Caribbean, from which it has radiated out in all directions. In various articles Davenport has pointed out that even between the extreme northern varieties, irradians and borealis, which would otherwise be specifically separated from gibbus, there is a very complete and gradual intergradation. In adapting themselves to colder climates the individuals of the species tend to become less convex, with the ribs rounder and more widely spaced. The same tendency is shown much less strongly by cequisulcatus, the northern form from the Pacific coast. It is possible that Pecten eboreus Conrad and its varieties, including perhaps the forms here described as varieties of P. deserti, may be the ancestors of Pecten gibbus. They appear to have radiated from the common center so as to arrive in most regions just ahead of the varieties of gibbus, though some of them managed to live on for some time after the arrival of the latter species. In some cases it is difficult to distinguish the two. The typical variety of Pecten gibbus is characterized by moderate size; strong con- vexity of the valves, the right valve more convex; 17 to 23 ribs, averaging 20 with a tendency toward a slight reduction in number in the fossils, ribs fairly high and flat- topped; obliquity averaging 6%; and a wide range of coloration, usually of bright colors. Variety amplicostat^us Dall has but 15 or 16 ribs, which are broader and more solid; and it is usually white on the right valve and mottled gray on the left. Variety nucleus Born has 21-23 ribs, is smaller, thinner, and polished, variegated with gray, white, and dark brown. Variety irradians Lamarck has from 17 to 22 ribs, averaging 19, the ribs varying from angulated to rounded, sometimes showing strise as in P. opercularis Lamarck, the type of the subgenus Aequipecten. It is less convex than typical gibbus, has a somewhat thinner shell and more sombre coloration, preferring deeper water. Variety borealis Say is like irradians, being but a more extreme variation in the same direction, with rounded, fewer, more distant ribs, and lower convexity, the two valves becoming almost equally convex. Variety venezuelanus F. and H. Hodson has about 19 fairly broad, flat-topped ribs, strong convexity, the right valve being the more convex, and has an estimated obliquity of about 11%. Variety cornellanus F. and H. Hodson recalls the description of ampUcostatus, with 17 or 18 fairly broad, square-sided, flat-topped ribs, and (according to Hodson's 218 San Diego Society of Natural History [Memoirs figures) a low obliquity as in gibbus, s. s. Variety caucanus F. and H. Hodson is like variety venezuelanus but with riiore prominent striations on the ribs. The other varieties will be more fully described below. Pecten (Aequipecten) gibbus (Linnaeus) variety circularis Sowerby Plate 5, Figures 7a, 76, 7c Peclen tumidus Sowerby, Proc. Zool. Soc. London, p. 109, 1835, not Peclen tumidus Turton, 1822, nor Zeiten, 1830. Pecten circularis Sowerby, Proc. Zool. Soc. London, p. 110, 1835; Thes. Conch., Vol. 1, p. 51, pi. 12, fig. 23, 1842; Reeve, Conch. Icon., Vol. 8, Peclen, pi. 31, species 137, 1852; Weymouth, Calif. Fish and Game Comm., Fish BuU. No. 4, p. 24, pi. 1, figs. 1, 2, 1920. Not Pecten circularis Goldfuss, Petrifacta Germanise, Vol. 2 (pt. 5), p. 76, pi. 99, figs. 10a, 106, 1836, Ed. 2, p. 72, pi. 99, figs. 10a, 106, 1862. Peclen ventricosus Sowerby, Thes. Conch., Vol. 1, p. 51, pi. 12, figs. 18, 19, 26, 1842, new name for P. tumidus; Reeve, Conch. Icon., Vol. 8, Pecten, pi. 7, species 31, figs, a, b, 1852; Gabb, Geol. Survey Calif., Palso., Vol. 2, p. 104, 1868-9; Kuster and Kobelt, Martmi-Chemnitz Syst. Conch. Cab., Ser. 2, Vol. 17, Pt. 2, p. 100, pi. 28, figs. 1-3, 1888; Cooper, 7th Annual Report, Calif. St. Mineralogist, p. 258, 1888; Davenport, Mark Anni- versary Volume, pp. 123-136, pi. 9, 1903; Keep, West American Shells, p. 41, 1904; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 256, 1909; Peile in Bosworth, Geol. and Paleo. of N. W. Peru, p. 178, pi. 25, fig. 10, 1922 (MacMiUan & Co., London). Pecten [ventricosus var. ?] seqtiisidcatus Carpenter, Brit. Assn. Adv. Sci. Rept. for 1863, p. 645, 1864; Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 179, 1865; Dall, Trans. Wagner Free Inst. Sci., PhOa., Vol. 3, p. 711, 1898. Pecten (Dentipecten) circularis Sowerby, Kuster and Kobelt, Martini-Chemnitz Syst. Conch. Cab., Ser. 2, Vol. 17, p. 188, pi. 51, figs. 5-8, 1888. Pecten xquisulcalus Carpenter, Kuster and Kobelt, Martini-Chenmitz Syst. Conch. Cab., Ser. 2, Vol. 17, p. 269, pi. 71, figs. 1, 2, 1888; Keep, West Coast Shells, p. 166, fig. 139, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 193, (1892) 1893; Orcutt, West American Scientist, Vol. 12, p. 11, 1901; Williamson, Bull. So. Calif. Acad. Sci., Vol. 1, r.o. 5, pp. 51-64, pis. 4-6, 1902; Keep, West American Shells, p. 39, fig. 18, 1904. Pecten (Pecten) compactus Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 707, pi. 34, fig. 5, 1898; figure re- produced by Arnold, Prof. Paper 47 U. S. Geol. Survey, pi. 44, fig. 7, 1906. Pecten {Plagioctenium) subvcntricosus DaU, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 707, pi. 29, fig. 8, 1898; figure reproduced by Arnold, Prof. Paper 47 U. S. Geol. Survey, pi. 44, fig. 5, 1906. Pecten {Plagioctenium) ventricosus Sowerby, Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 710, 1898 (-1- P. inca d'Orbigny 1847, = ? P. pomata Valenciennes, Voy. Venus, pi. 19, fig. 3, 1835, fide Dall); Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 114, pi. 11, figs. 3, 3a, 6, 6a, 1903. Pecten {Plagioctenium) newsomi Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 113, pi. 11, figs. 1, la, 1903. Pecten (Plagioctenium) circularis Sowerby, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 125, pi. 42, figs. 3, 4, 5, 6, pi. 44, figs. 6, 6a, 66, 7, 1906; Eldridge and Arnold, Bull. 307, U. S. Geol. Survey, p. 242, pi. 35, fig. 4, 1907; Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 58, 1924; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 214, pi. 23, fig. 9, 1926; also p. 438, in part, 1926. Pecten (Plagioctenium) circularis var. asquisulcatus Carpenter, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 132, pi. 50, figs. 1, la, 16, also text figure 1 on p. 45 and 2 on p. 46, 1906; Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 58, pi. 42, figs. 1, 2, 1924. Pecten (Plagioctenium) calli Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 16, pi. 4, fig. 6, not figs. 5 and 7, (fig. 6 is of the type), 1925; Jordan and Hertlein, Vol. 15, p. 436, pi. 27, fig. 5, 1926. Pecten (Chlamys) circularis sequisulcatus Carpenter, Waterfall, Univ. Calif. Publ. Geol., Vol. IS, p. 78, 1929. ? Pecten (Plagioctenium) ericellus Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. IS, p. 215, pi. 24, figs. 10, 11, 1929. Like the typical variety in all respects except that the obliquity (as explained above) averages 15% instead of 6%, that is, more specimens are drawn out obliquely than is the case with the typical variety. Dimensions: Altitude, 44 mm.; length, 46 mm.; length of hinge, 33 mm.; convexity of right valve, 15 mm., of left valve, 12 mm. Type specimens: Of circularis, ventricosus, and cequisulcalus, British Museum (?); of compactus and subvcntricosus, both No. 61,246, and of newsomi, No. 162,524, in the U. S. National Museum; of calli, No. 68 in the collection at Stanford University; of ericellus, No. 2,998 at the California Academy of Sciences. Type localities: Of circularis, living. Gulf of California; of ventricosus, living, west Colombia; of asquisulcatus, living, Santa Barbara, Calif.; of compactus and subvcntricosus, Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 219 Pleistocene of Ventura Co.; of newsomi, Pleistocene of Signal Hill (Los Cerritos), Los Angeles Co.; of calli, east of Santiago, Lower California, probably Pliocene; of ericellus, Pliocene of Pacific Beach, San Diego. Pliocene: Lower California (Jordan and Hertlein as circularis and as calli, though part of the occurrences listed as circularis may be closer to variety dcmiurgus Dall — those with the "rounded ribs"); (Plio- cene ?) Cholas Valley, near San Diego (Stearns in Arnold 1906); ? Pliocene of Pacific Beach, San Diego (Hertlein as ericellus). Pleistocene: Ventura, San Pedro, San Diego (Arnold, etc., also as var. aequisulcalus) ; "Saugus" of Ventura County (Waterfall); Lower California (Jordan and Hertlein); Borego Springs, Colorado Desert (Orcutt). Living: Monterey, Calif., to Payta, Peru (Dall, 1921); as ^guisulcatus, Santa Barbara, Calif., to Cape San Lucas, Lower Calif. (Dall, 1921). The long list of synonyms bears witness to the great variability of this variety. Conchologists have long tried to keep ventricosus separate from circularis, but now it is generally acceded that the two are nearly identical. Some conchologists still try to keep variety cequisulcatus separate on the grounds that it is a larger and less convex form. Arnold gives for its dimensions : Alt., 72 mm. ; long., 83 mm. ; hinge line, 51 mm. ; diameter, 36 mm. ; umbonal angle 100°. It is also said to have a thinner shell, narrower ribs, and more subdued coloration, which recalls the analogous variety irradians of the Atlantic coast, though the modification has not gone so far with cequisulcatus. The range also appears to have a significance, for this variety is said not to occur outside of California and the west coast of Lower California. Hence it may be found desirable to attempt the separation of Pecten gibbus var. cequisulcatus, though it would be just as easy, when the forms are so much alike, to remember it as the northern modification of variety circularis. W. C. Mansfield of the U. S. National Museum very kindly informed the writers after examining the types of compactus and subventricosus that he believed them to be the right and left valve of P. circularis respectively. Arnold himself listed newsomi as the young of cequisulcatus. Hertlein accedes that calli is but the young or a stunted localized form of circularis. The form ericellus is an individual variant in the evolutionary series between P. purpuratus and P. gibbus variety circularis; but it has already advanced far enough so that it can be matched in all its characters, ventricosity, number and character of ribs, and secondary ribs, by young living specimens of the form cequisulcatus, and hence should be assigned here. In some respects it resembles the varieties of P. deserti from the middle Pliocene of the Ventura basin, but it has too many ribs. Pecten (Aequipecten) gibbus (Linnseus) variety demiurgus Dall (?) "Pecten comparilis Tuomey and Holmes," Guppy, Geol. Mag., Decade 2, Vol. 1, 1874. Pecten (Plagioctenium) demiurgus Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 718, pi. 26, fig. 3, 1898; Maury, BuUs. Amer. Paleo., No. 42, p. 85, or Vol. 10, p. 237, pi. 14, fig. 5, pi. 16, fig. 6, 1925. "Pecten {Plagiocteniu7n) ccrrosensis mendenhalli Arnold," Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 16, pi. 1, fig. 5, 1925. Pecten (Plagioctenium) abietis Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 214, pi. 23, figs. 1, 3, 7, 1926. "Pecten (Plagioctenium) circularis Sowerby" Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 438, 1926. "Pecten (Plagioctenium) mendenhalli Arnold" Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 442, 1926. Type specimens: Of demiurgus, No. 115,527 in the U. S. National Museum; of abietis, No. 2,079 at the California Academy of Sciences. Type localities: Of dem,iurgus, Miocene of Trinidad; of abietis, Pliocene of Maria Madre Island off the southwest coast of Mexico. 220 San Diego Society of Natural History [Memoirs Miocene: Trinidad (Guppy; Dall; Maury). Pliocene: Lower California (Jordan and Hertlein). This variety is distinguished by its large size, twenty strong, broadly rounded ribs with very narrow interspaces, its moderate convexity, with the right valve usually a little more convex, and obliquity like that of the variety circularis. The original description stresses the high, narrow umbones and inset ventral ears, and one of the specimens in the Stanford collection from Lower California agrees in these respects with the type description and figure ; but other specimens from the same locality which are almost surely the same are of a more normal shape, and Miss Maury's figure of a specimen from the type locality in Trinidad does not show the shape of the type ; in- deed. Miss Maury's figure bears in some respects a closer resemblance to the variety cequisulcatus than it does to demiurgus. At all events, it seems to be the shape of ribs and the narrow interspaces, with the size and moderate convexity, that characterize this variety, and the narrow umbones are not essential. Hertlein no longer holds that the forms from Lower California ascribed by him to mendenhalli are the true mendenhalli of Arnold. Indeed, it seems probable that the rounded ribs of the form described by Hertlein as well as the triangular ribs described by Jordan and Hertlein as the characteristic of abietis are a peculiar result of weathering, for one specimen shows patches of rounded ribs and of triangular ribs on the same valve. Some of the specimens of "P. circularis" with the "rounded ribs" reported by Jordan and Hertlein from Lower California probably also belong here. This variety appears to have migrated from the Atlantic to the Pacific along with the typical variety. Pecten (Aequipecten) hallae Dall Peden (Plagiocleniuvi) hallx Dall, Nautilus, Vol. 34, p. 76, 1921. Type specimen: No. 33,042 in the U. S. National Museum. Pliocene ?: Nome, Alaska. This species has not been figured, and the description alone is not sufficient to show its relationships. Apparently it has a right valve like that of P. gibbus var. circularis (or cequisulcatus), but it is much larger (altitude 120 mm. or more). Subgenus JANIRA Schumacher, 1817 Vola Ivlein, 1753, pre-Linnsean. Peclen Miiller, 1776, in part only (see reference under Pecten, s. s.) ; Bolten, Mus. Boltenianum, p. 165, 1798; Lamarck, Prodr., Mem. See. Hist. Nat. Paris, Ser. 1, Vol. 1, p. 88, 1799; Children, Quart. Journ. Sci., Lit., Arts,. Vol. 15, p. 40 (pi. 2, fig. 89), April, 1823, type designated, Pecten maximus = Oslrea maxima Linnaeus; Gray, Proc. Zool. Soc. London, p. 200, 1847, type cited, Oslrea maxima Linnseus; Dall; Arnold; Woodring; etc. Pandora Megerle von Miihlfeld, 1811, not of Bruguiere, 1792, nor of Hwass in Chemnitz, 1895, nor of Lamarck, 1799. Janira Schumacher, Ess. Nouv. Syst. Hab. Vers. Test., pp. 40, 117, 1817. Type (by original designation), Janira intermedia Schumacher, p. 118, pi. 3, fig. 4, probably the same as or a variety of Pecten maximus, though the grooves and ridges di- verging from the resilial pit are shown to curve out farther; Recent, Norway to the Mediterranean. Shell with the right valve convex and the left nearly flat, sometimes concave, sculptured with a moderate number of ribs, which are sometimes radially striate; ears nearly equal, usually squarely terminated, the byssal notch almost obsolete. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 221 Geologic range: Eocene to Recent, possibly older. Distribution: Warm and temperate waters of all oceans. The Mesozoic subgenus Nerithea Drouet has the same general form as Janira, but it is quite likely that it was derived from Chlamys independently, and the writers are for the present incUned to think that Janira comprises a group of species of not very great antiquity, not any more distinct from Chlamys than the other subgenera. Section Janira, s. s. Ribs strong and radially striate. Section Notovola Finlay, 1926 Notovola Finlay, Trans. New Zealand Institute, Vol. 57, p. 451, 1926; Marwick, Vol. 58, p. 448, 1927. Type (by original designation), P. novcezelandice Reeve, Conch. Icon., Vol. 8, Pecten, pi. 8, species 36, 1852, living. New Zealand. Ribs not radially striate. Marwick mentions that P. laqueatus and P. bellus should be referred to this section. The writers believe that this section is of practically no significance and that it may do more harm than good to separate it from the typical, perhaps dividing related species. The Pliocene Janiras may be thought of as a series varying from the flat forms like P. bellus and stearnsii to the very convex vogdesi. There are six species. The first is rather distinct from the others, being most closely related to P. bellus. It is represented by the form aletes Hertlein, which is probably only a variety of P. humphreysii Conrad from the Miocene of Maryland and of P. laqueatus Sowerby now living in Japan. This form is characterized by its few, broad, flat-topped ribs. It may have been derived from P. vanvlecki Arnold,' a lower Miocene species. The other species are all more or less inter- grading. P. stearnsii and its varieties have a depressed form and numerous ribs, which often have a tendency to be grooved. P. bellus has a moderate number of ribs, and typically is depressed; but in the varieties hemphilli and coaUngaensis the right valve becomes more convex, and these forms eventually grade over into P. vogdesi. P. vogdesi has a very convex right valve, with rounded ribs, and on the left valve strong intercalaries. P. hartmanni Hertlein has also a very convex right valve, but it has a narrow shell and few ribs. P. keepi is a P. vogdesi on which the ribs have become nearly obsolete. Pecten ( Janira) humphreysii Conrad Pecten humphreysii Conrad, Bull, of the Proc. of the National Institute for the Promotion of Science, Washington, D. C, No. 2, p. 194, pi. 2, fig. 2, 1842, published before the American Journal of Science, Vol. 43, Pt. 1, p. 216, April to June, 1842. Pecten laqueatus Sowerby, Thes. Conch., Vol. 1, pt. 2, p. 46, pi. 15, fig. 101, 1842, publi-shed between August 1 and November 2, 1842. Vola humphreysii Conrad, WTiitfield, Monograph 24 U. S. Geol. Survey, p. 32, pi. 4, figs. 6, 7, 8, 9, 1894. Pecten (Pecten) humphreysii Conrad, Glen, Maryland Geol. Survey, Miocene Volume, p. 372, pi. 98, figs. 10, 11, 12, 1904. Shell of moderate size, right valve of moderate convexity, sculptured with seven or eight large, broad, flat-topped ribs and one or two minor ribs at each side; left valve nearly fiat, with a similar number of low, squarish, narrow ribs ; ears nearly smooth or finely, radially striate. 1 Pecten {Pecten) vanvlecki Arnold. Smithsonian Misc. Coll., Vol. 50. Pt. 4, p. 10, (separate pagination), pi. 5.3. figs. 1. 2, 1807. figures reprinted in Bull. 322 U. S. Geol. Sur\'ey, pi. 17, figs. 1, 2. 1907. 222 San Diego Society of Natural History [Memoirs Miocene: Maryland, New Jersey, etc. (Conrad; Whitfield; Glenn). Miocene-Pliocene: Lower California (see the variety aletes). Living: Japan. The two well-known forms, humphreysii and laqueaius, are so very much alike that they probably cannot be distinguished and are here tentatively considered synonymous in spite of their very distant occurrences. The variety aletes explains and unites these two widely separated occurrences, for it is a form probably not more than varietally distinct, being apparently a local off-shoot that separated from the main stock as it migrated from Maryland to Japan. Whether the synonymy as given above be accepted or not, the fact of primary importance cannot be doubted that this species or group of forms migrated, probably during the Miocene, between Maryland and Japan through Cali- fornia. A single instance of this sort is sufficient to prove that the provincialism of the California faunas is entirely mythological and to show that migration has occurred be- tween this region and others, that some species must have come here from the other regions, and that therefore the faunas of the other regions must be taken account of and some of the specific names applied to California forms. Furthermore, this instance does not occur alone but is accompanied by many others. The Pectens supply the cases best known to the present writers, who have studied them more with this idea in mind, but similar cases have been noticed in other genera such as Corbula, Psephoea, Nucula, Pilar (Amiantis) , Mactra, etc. Provincialism has deprived California paleontologists of one of the most helpful aids in making correlations and has kept in the dark some of the most interesting chapters of this part of natural history. Pecten ( Janira) humphreysii Conrad variety aletes Hertlein Peclen (Pecten) aletes Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 8, pi. 2, figs. 1, 4, 1925. Shell like that of the typical variety, but with higher, more T-shaped ribs on the right valve, these ribs more strongly overhanging the interspaces, which on the right valve are consequently wider and allow the ribs of tJie left valve to be wider also; a few indistmct longitudmal grooves present on the tops of the ribs of the right valve. Dimensions: Altitude, 62 mm.; length, 65 mm.; length of hmge, about 32 mm.; diameter of right valve (possibly somewhat crushed), 13 mm. Type specimen: No. 44 in the type collection at Stanford University. Type locality: North of San Jose del Cabo, Lower California. Upper Miocene or loxoer Pliocene: Type locality. The main stock of this species is so variable that it is not certain whether the char- acters separating this variety are significant or not. Pecten (Janira) steamsii Dall "Janira dentata Sowerby" Gabb, Geol. Survey Calif., Palso., Vol. 2, p. 104, 1868-9, in part^ .\rnold; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 244, 1888, in part fide Arnold. Pecten steamsii Dall, Proc. U. S. Nat. Mus., Vol. 1, p. 14, 1879. Pecten (Pecten) steamsii DaU, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 706, pi. 26, fig. 5, 1898; Arnold, Mem. Calif- Acad. Sci., Vol. 3, p. 106, pi. 12, fig. 3, 1903; Prof. Paper 47 U. S. Geol. Survey, p. 100, pi. 32, figs. 1, la, 1906; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pp. 152, 153, pi. 35, fig. 2, pi. 36, fig. 4, 1907; Arnold and Anderson, Bull. 322, p. 59, pi. 25, figs, la, 16, 1907; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 417, 1926. Pecten (Pecten) beali Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 10, pi. 2, fig. 3, pi. 5, fig. 8, 1925. VoLTJME I ] Pliocene and Pleistocene Mollusca of California 223 Shell about 70 mm. in diameter, subcircular, piano or concavo-convex, fairly thin; right valve of low convexity, with 18 to 24 regular, even, squarish ribs, separated by interspaces somewhat narrower than the ribs, the top surface of each rib flattened and often grooved or sulcated; ears nearly equal, arched, covered with crowded, elevated lamellae and sometimes inchstinct radiating ridges, byssal notch very small ; left valve flattened or concave, with regularly rounded, even ribs, separated by shghtly wider interspaces, which sometimes have an inconspicuous mid-rib, the whole surface cov- ered with fine, sharp, concentric, regular lamellse; ears of this valve concave, with indistinct radiating ridges and fine concentric lamellse. Dimensions: Altitude, 62 mm. : lorgitude, 71 mm. ; diameter, 14 mm. ; length of liinge, 25 mm. This species is represented by a somewhat limited series of variations which are prob- ably closely related genetically with Pecten bellus and its varieties. Variety steamsii, s. s. Plate 3, Figures 2a, 2b Type specimens: Of steamsii, No. 7,942 in the U. S. National Museum; of heali, No. 55 in the type collection at Stanford University. Type localities: Of stearr^sii, Pliocene of San Diego; of beali, from arroyo near La Palma, Lower California, Salada contact. Pliocene. Pliocene: Pacific Beach, San Diego (Dall; Arnold); Santa Maria district (.\rnold, 1907); Temescal Canyon> Santa Monica Mts., Los Angeles Co. (Watts; Rivers in Arnold); Lower California (Hertlein; Jordan and Hertlein; partly as beali); loc. 217a S. D. S. N. H., middle Pliocene of Holser Canyon, Los Angeles Co., three specimens, one of which has no sulcations on the ribs (H. R. G.); loc. 228, middle Pliocene southeast of Pico Canyon, Los Angeles Co., three large specimens none of which have sulcations on the ribs (H. R. G.); Third Street tunnel, Los ^\ngeles (.Arnold). Pleistocene: "Pliocene" of San Pedro (Arnold 1903). ? Ldving: Some living specimens look as much like this variety as they do like diegensis. This typical variety is distinguished by its numerous ribs (23-24, possibly even 26), the ribs when characteristic being high and comparatively narrow, and on the right valve more or less deeply grooved, the hinge line very short, less than half the length of the shell. The distinction is drawn more according to the number of the ribs and the length of the hinge hne than according to the sulcations on the ribs, for many living specimens have grooved ribs and many fossils have entire ribs. The distinction is of doubtful value. The form beali is too close to separate, though the type specimen is interesting, as it shows a tendency for the two parts of the sulcated ribs to split again like the ribs of Area trilineata. Pecten ( Janira) steamsii Dall variety diegensis Dall Plate 3, Figure 4 "Pecten floridus Gmelin," Hinds, Zool. Voy. Sulph., p. 60, pi. 17, fig. 6, 1844; Reeve, Conch. Icon., Vol. 8, Pectm, pi. 8, fig. 34, 1852. "Pecten (Vola) floridus Gmelin," Kiister and Kobelt, Syst. Conch. Cab., Vol. 17, pi. 57, fig. 2, 1888. "Janira florida Gmelin," Cooper, 7th. Ann. Rept. Calif. St. Mineralogist, p. 244, 1888. Pecten (Pecten) diegensis Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 710, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 106, pi. 12, fig. 5, 1903; Prof. Paper 47 U. S. Geol. Survey, p. 127, pi. 51, figs. 1, la, lb, 1906; Dall, Bull. 112 r. S. Nat. Mus., p. 18, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 51, pi. 29, fig. 5, pi. 41, fig. 3, 1924; WaterfaU, Tniv. Calif. Publ. Geol,, Vol. 18, p. 78, 1929. Pecten diegoemtis DaU, Keep, West. Amer. Shells, p. 39, 1904. Type specimen: No. 150,980 in the U. S. National Museum. Type locality: Living, San Pedro, Los Angeles Co. 224 San Diego Society of Natural History [Memoirs Pliocene: Middle Pico of locality 226, Ventura County, one specimen (H. R. G.) ; uppermost Pliocene of Ven- tura Co. (Waterfall). Pleistocene: San Diego (Hemphill in Arnold). Living: Monterey Bay to San Diego and the Cortez Bank (Dall) ; in all cases dredged (Arnold). This variety is distinguished from the typical form by its fewer ribs (18 to 21), with wider interspaces, and by its generally longer hinge line. The ribs are usually lower and are less often sulcate. The right valve may be flatter than that of the typical variety, in which case the left valve becomes somewhat convex. This variety is distinguishable from the typical variety of Pecten bellus by its longer hinge line and larger number of ribs. The single specimen collected from locality 226 is much like the living specimens, having low convexity, 18 medium high, squarish, non-sulcated ribs, and a hinge line about half as long as the shell. If the characters of the variety diegensis are to be depended upon at all, this specimen must be included, even though it comes from a horizon thought to be of middle Pico age. The ribs are a little wider than on living diegensis, this form being apparently a connecting link with bellus. Locality 226 is near the mouth of Smith Canyon, the first canyon east of Torrey Canyon, south of the town of Piru, Ventura County, directly overlying hard calcareous Modelo sandstones, and described by Kew (1924) as basal Pico. It is thought by the writers, however, to be of middle Pico age, the basal Pico not being represented in that particular locality. Among the living and fossil specimens, there are some which have the number of ribs typical of stearnsii, s. s., but have the shape of ribs characteristic of diegensis. There are others with longer ears. The ultimate distinction is made on the basis of the number of ribs, and not upon the shape. Pecten (Janira) stearnsii Dall varietj' carrizoensis Arnold Pecten sp. indet., Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 706, line 13, 1898, fide Arnold. Pecten (Pecten) carrizoensis Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 59, pi. 4, figs. 1, la, 16, 2, 3, 3a, 1906; Hert- lein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 2, 1925; Hanna and Hertlein, Vol. 16, p. 141, 1927. Pecten carrizoensis Arnold, Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 470, 1926. Type specimen: No. 11 in the type collection at Stanford University. Type locality: Head of Garnet Canyon, about 12 miles north of the Mexican boundary in the Carrizo Creek district. Pliocene: Carrizo Creek district (Arnold; Hertlein; Hanna); Santa Rosalia, Lower California (Arnold); Santa Antonita Point, Lower California (Hanna and Hertlein); "Miocene" of San Diego (Dall). This variety is a smaller stunted form with fewer ribs (18), otherwise indistinguish- able from the variety diegensis and the typical stearnsii- Pecten (Janira) stearnsii Dall variety bakeri Hanna and Hertlein Plate 4, Figures la, 16 Pecten (Patinopecten) bakeri Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 153, pi. 5, fig. 1, 1927. Pecten (Pecten) bosei Hanna and Hertlein, Proc. Calif. Acad. Sci,, Ser. 4, Vol. 16, p. 154, pi. 5, figs. 2, 3, 1927. Shell like that of the typical variety but with low, smooth, slightly flat-topped ribs, the inter- calary between the ribs well developed on the left valve, and on large specimens faintly showing on the right also. Dimensions : Altitude, 113 mm., length, about 122 mm.; length of hinge, about 55 mm.; convex- ity of right valve, 15 mm., of left valve, 4 mm. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 225 Type specimens: Of bakeri, No. 1,865, of bosei, Nos. 2,215 and 2,216 (cotypes), at the California Academy of Sciences. Type localities: Of bakeri, 15 miles north of Loreto, Lower California; of bosei, near Santa Antonita Point, Lower California. Pliocene: Type localities, Lower California; loc. 32, S. D. S. N. H., Santa Rosalia, Lower California, one fine specimen (collected by Marcel Touwaide). The two forms described by Hanna and Hertlein in the same paper and figured on the same plate do not look at all alike in the original illustration. Indeed, one was assigned to a different subgenus. Fortunately, however, the specimen herewith figured, which is much better than the type of bakeri, and has both valves well preserved, shows beyond a shadow of a doubt that bakeri is a Janira and that bosei is the young of it. The original illustration of bakeri is misleading, for it makes the ribs look very broad and shows the shallow sulcations in a peculiar manner. What appears to be a rib in the original illustration is really the entire area between a mid-rib and the far side of the first main rib to the right. Pecten (Janira) bellus (Conrad) Janira bella Conrad, Proc. Acad. Nat. Sci., Phila., for 1856, p. 312, 1857, reprinted by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 173, 1909; U. S. Pacific Railroad Survey, Reports, Vol. 6, p. 71, pi. 3, fig. 16, 1867, description reprinted by Dall, op. cit., p. 178, 1909; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 244, 1888. Pecten (Pecten) bellus Conrad, Dall, Trans. Wagner Free Inst. Sci., Phila., p. 704, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 103, pi. 21, figs. 1, 2, 1903; Prof. Paper 47 U. S. Geol. Survey, p. 95, pi. 31, figs. 1, la, 1906; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, p. 24, pi. 35, fig. 3, 1907; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 4.30, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, pp. 78, 81, 82, 1929. Pecten bellus Conrad, Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, p. 151, 1912; McLaughlin and Waring, Map Folio accompanying Bull. No. 69, Calif. St. Mining Bureau, pi. 1, fig. 46, 1914; Kew, Bull. 753 U. S. Geol. Survey, p. 88, 1924. Shell moderately large, not very thick, varying in convexity from forms with a moderately arched right valve, which necessitates a distinct bulge in the left valve to provide the animal room to live, to forms with a strongly arched right valve and a slightly concave left, the umbones being in a few cases strongly arched and the later growth of the shell more expanded and flattened; ribs varying in number from about 12 to 18, either Ijroad and square and not very high, or tending toward higher, narrower, or more rounded shapes, but in all cases rather widely spaced, enlarging noticeably toward the periphery', the whole surface of the shell ornamented with close, fine growth lines; hinge line short, only about half the length of the shell or slightly shorter, ears not long, but fairly deep, nearly equal, the right ventral somewhat arcuate but with hardly any byssal notcli, marked with about four low, rounded, radiating riblets, the other ears almost squarely terminated, without the riblets, on some varieties the ears of the right valve noticeably convex or folded, those of the left smoothly concave. This series of variations has been described as five distinct species, and all of the forms have not yet been named. Jordan and Hertlein have shown that two of the most distinct, bellus and hemphilli, intergrade perfectly in Lower California and are very difficult to distinguish there or even at San Diego. All of the other varieties are less distinctly characterized, probably representing nothing more than minor reactions to local condi- tions, and some of them it is hardly worth while to try to recognize. Variet}' bellus, s. s. Right (lower) valve only moderately convex, the pomt of greatest convexity being about one- third of the distance from the hinge to the posterior margin of the disk, the umbo curving sharply in some specimens and meeting the plane of the ears perpendicularly; ribs prominent, 12 to 15 in num- ber, broad, flat-topped, with flat, steeply sloping sides, sometimes marked by one or two indistinct longitudinal grooves, growing broader, less elevated, and less sharply angled near the periphery; 226 San Diego Society of Natural History [Memoibs hinge line short; left valve only slightly convex, outline smoothly curving or varied with a depressed area just under the beaks; ribs much as in the right valve, but narrower and higher, more distant, sometimes slightly grooved in the center. Dimensions of a large specimen from the type locaUty: Altitude, 98 mm.; length, 105 mm.; length of hinge, 48 mm.; convexity of right valve, 25 mm., of left valve, 5 mm. Type locality : Uppermost Pliocene near Santa Barbara. Middle Pliocene: San Deigo and Lower California (Jordan and Hertlein). Upper Pliocene: Santa Barbara (Conrad; Cooper; Gabb; Arnold); Dry Canyon, north branch of Tapo Canyon, Ventura County (Kew); east side of Piru Creek, Ventura County (Watts); locality 221, Canada de Aliso, Ventura County, ten fragments (H. R. G.); ? Temescal Canyon north of Santa Monica, Los Angeles County (Rivers). Typical belhis is distinguished from its varieties by the more moderate convexity of its right valve, by the usually somewhat convex left valve, and by its broader, squarer ribs. From typical stearnsii it is distinguished by the fewer, broader ribs on the right valve, and the less strongly laminated ribs on the left valve; from stearnsii variety diegensis it is also distinguished by its shorter hinge line. It approaches distantly the form of Pecteti huviphreysii. Pecten (Janira) bellus (Conrad) variety hemphilli Dall Plate 3, Figures la, 16 Pecten hemphilli Dall, Proc. U. S. Nat. Mus., Vol. 1, p. 15, 1879; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 257, 1888; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, pp. 150, 151, 152, 1912; Kew, BuU. 753 U. S. Geol. Survey, pp. 78, 88, in part ?, 1924. Pecten (Pecten) hemphilli Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 706, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 105, 1903; Prof. Paper 47 U. S. Geol. Survey, p. 97, pi. 33, figs. 3, 3a, 3b, 1906; Arnold and An- derson, Bull. 322 U. S. Geol. Survey, p. 59, pi. 25, fig. 5, 1907; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 45, 1916. Pecten (Pecten) auhvryi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 94, pi. 33, figs. 2, 2a, pi. 34, figs. 2, 2a, 1906; Eldridge and Arnold, BuU, 309 U. S. Geol. Survey, p. 153, pi. 35, fig. 7, 1907. Pecten [Pecten) leconlei Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 98, pi. 33, figs. 4, 4a, 46, 1906; Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 2, 1925. Pecten (Pecten) bellus Conrad, Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 430, in part, pi. 32, fig. 2, pi. 33, figs. 1, 2, pi. 34, figs. 2, 3, 4, 1926. Shell like that of bellus, s. s., and grading into the typical variety, but characterized by a greater number of ribs (14 to 18, — in auburyi "16 to 17," in lecontei "about 17"), the ribs of both valves being generally higher, narrower and rounder; right valve more strongly convex, left valve concave (or flat in forms close to bellus, s. s.); shell often smaller. Dimensions: Altitude, 60 mm.; length, 66 mm.; length of hmge line, 29 mm.; convexity, 17 mm. Type specimens: Of hemphilli, No. 7,943 in the U. S. National Museum; of leconlei, No. 4 in the type collection at Stanford University. Type localities: Of hemphilli, Pliocene of San Diego; of auburyi, 1 mile east of the Chandler wells, Puente Hills, Los Angeles Co.; of lecontei. Pliocene of Cedros Island, Lower California. Pliocene: Type localities; also Temescal Canyon north of Santa Monica (Rivers in Arnold); Santa Maria, Santa Barbara Co. (Arnold as auburyi); Turtle Bay, Lower California (Jordan and Hertlein); ? Santa Clara Valley, Ventura and Los Angeles counties (Kew, in part ?); Fourth and Broadway, Los Angeles (Moody). The form auburyi is a little more extreme in its characters than is the type of hemp- hilli, but not significantly so, being a little more convex, which makes the apical angle look smaller; the form lecontei has shghtly lower and rounder ribs. These forms differ from hemphilli less than hemphilli differs from bellus, and they appear to have no strati- Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 227 graphic and only a local geographic significance. Jordan and Hertlein probably were right in not considering bellus and hemphilli distinct species, but it seems to be advisable to preserve the distinction between them as varieties. In Ventura County they appear to have a stratigraphic significance, hemphilli grading upwards into bellus. The variety hemphilli is distinguished from the variety coalingaensis by its fewer ribs and by the broader tops and steeper sides of the ribs. It is distinguished from Pecten vogdesi Arnold by its fewer, squarer, more distant ribs, by its shorter hinge line, and by the absence of the mid-rib which is often present on the left valve of vogdesi. Pecten (Janira) bellus (Conrad) variety coalingaensis Arnold in Anderson Plate 2, Figure 2 Pecte7i coalingaensis Arnold, F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 3, Vol. 2, p. 197, pi. 18, figs. 94-98, 190.5. Pecten (Pecten) coalingaensis Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 97, pi. 4, figs. 4, 4a, .5, 1906. Pecten coalingaemis Arnold, Bull. .396 U. S. Geol. Survey, pp. 31, 3.5, 39, 42, 44, pi. 26, figs. 1, 2, 1910; .\rnold and R. Anderson, Bull. 398 U. S. Geol. Survey, pp. 101, 119, 129, 132, 136, 137, 138, pi. 48, same figures, 1910. Pecten coalingensis Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 219, 1917. ? Pecten hemphilli Dall, Kew, Bull. 753 U. S. Geol. Survey, pp. 78, 88, in part ?, 1924. Shell like that of the variety hemphilli but typically with more triangular ribs on the right valve, the rib.s with narrow, somewhat rounded tops and sides sloping at an angle of about 45° to the narrow bottoms of the interspaces, ribs 17-20 in number. Type specimen (the one figured by Arnold, 1906, which may or may not be the type, as Anderson's publication appeared first) : No. 7 in the type collection at Stanford University. Type locality: Etchegoin formation, near Coalinga, middle California. M. Pliocene: Common but confined to the Pecten coalingensis zone of the Etchegoin (Nomland); ? Santa Clara Valley, Los Angeles Co. (Kew); ? loe. 228 S. D. S. N. H. southeast of Pico Canyon, Los An- geles Co., about ten left and ten right valves (H. R. G.) ; loc. 230, one, loc. 231, four (loc. 226, one ?), south side of the Santa Clara Valley (H. R. G.). It is probable that this variety should not be separated from hetnphiUi, for even at the type locality there are specimens with broader topped ribs and nearly vertical sides as in variety hemphiUi. The specimens from the S. D. S. N. H. localities are generally of smaller size, have a large number (17-20) of small, clearly defined, but lower, rounder, somewhat flat-topped ribs, with a very variable convexity and shape, and a tendency for the free margins of the shell to contract suddenly as if deformed. This form is as dis- tinct from coalingaensis as lecontei and auburyi are from hemphilli, but it seems hardly worthy of a name. It resembles lecontei in ribs, and coalingaensis in shape, especially those specimens of coalinga en.sis which do not have the characteristic sub-triangular ribs. Its significance as a relative of coalingaensis is greater than is its significance as a distinct (or abnormal) form. Pecten (Janira) bellus (Conrad) variety slevini Dall and Ochsner Plate 2, Figure 3 ? Pecten hemphilli Kew, Bull. 753 U. S. Geol. Survey, pp. 78, 88, 1924. Pecten [Pecten] skuiyii Dall and Ochsner, Proc. Calif. Acad. Sci., Ser. 4, Vol. 17, p. 118, pi. 3, fig. 9, pi. 4, fig. 4, 1928. Shell like that of varieties hemphilli and coalingaensis, Imt relatively much longer and with a somewhat crushed appearance. Dimensions : Altitude, 47 mm. ; length, 63 mm. : length of hinge, 27 mm. ; convexity of right valve, 15 mm. 228 San Diego Society of Natural History [Memoirs Type specimen: No. 2,944 at the California Academy of Sciences. Type locality: East shore of Indefatigable Island, Galapagos Group, probably Pliocene. Pliocene: Type locality; middle Pliocene of loc. 231 S. D. S. N. H., northwest of Pico Canyon, Los Angeles Co., one specimen (H. R. G.); of loc. 263, between Pico Canyon and the New hall tunnel, several specimens (H. R. G.), common in the same horizon north of the Santa Clara Valley, the top of the marine Pliocene (H. R. G.). This variety is probably a distorted form caused by the increasing brackishness of the water at the top of the marine sequence in the California locality. Like coalingaensis, this variety should probably be reunited to hemphilli. It is a variation in the opposite direction from atiburyi, which has a narrow, deep shell. Pecten (Janira) vogdesi Arnold Plate 3, Figures 3a, 36 Peclen dentatus G. B. Sowerby, Proo. Zool. Soc. London, p. 109, 1835; Thes. Conch., Vol. 1, p. 49, pi. 15, figs. 105-6, 1842, not Pecten dentaivs J. Sowerby, Min. Conch. Gt. Brit., Vol. 6, p. 143, pi. 574, fig. 1, 1829; Verrill, Trans. Conn. Acad. Sci., Vol. 10, p. 57, 1897. Not Pecten excavatus Anton, Verzeichniss der Conchylien, p. 19, No. 710, 1S39, correctly reported from China. Pecten sinensis Sowerby is a sjTionym of excavatus Anton. "Pecten excavatus Anton," Valenciennes, Voy. Venus, pi. 19, fig. 1, 1846. Vola dentata Sowerby, H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 554, 1853. Janira dentata Sowerby, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 645, 1864; Gabb, Geol. Survey Calif., Palaec, Vol. 2, p. 104, 1868-9; Cooper, 7th Ami. Rept. Calif. St. Mineralogist, p. 244, 1888. Pecten {Vola) dentatus Sowerby, Kusterand Kobelt, Martini-Chemnitz Syst. Conch. Cab., Ser. 2, Vol. 17, Pt. 2, p. 155, pi. 44, figs. 1, 2, 1888. Pecten (Pecten) dentatus Sowerby, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 104, 1903. Pecten {Pecten) vogdesi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 100, pi. 33, figs. 1, la, pi. 34, fig. 1, 1906 Eldridge and Arnold, BuU. 309 U. S. Geol. Survey, pi. 35, fig. 5, 1907. Pecten (Pecten) ixcavatus Anton, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 134, pi. 46, figs. 1, la, 16, 1906. Pecten (Euvola) cataractes Dall, Nautilus, Vol. 27, p. 121, 1914, new name for dentatus G. B. Sowerby. Pecten (Pecten) heimi Hertlein, Proc. Calif. .\cad. Sci., Ser. 4, Vol. 14, p. 9, pi. 1, fig. 3, pi. 3, fig. 3, 1925. Shell averaging about 90 mm. in altitude, about as long as high, plano-convex or slightly concavo-convex, equilateral, with more or less coarsely serrate margins, sides concave above; right valve very convex, the umbo projectmg above the hmge line, ribs about 20 in number, broad, low, and rounded, with interspaces aljout a quarter as wide, sometimes showing faint intercalary riblets or longitudinal striations; left valve usually slightly concave, sometimes strongly concave, with about 19 low, squarish ribs, about equal in width to the mterspaces, sometimes longitudinally sul- cated or ridged, interspaces flat-bottomed with usually a well-developed mid-rib, surface sculptured by fine concentric Imes; hinge line about three-fifths the length of the shell, ears equal, those of the right valve convex, folded over, rectangularly truncated, byssal ear with two or three mdistinct radiating ridges and concentric sculpture, other ears usually with concentric sculpture only. Dimensions: Altitude, 98 mm.; length, 107 mm.; length of hinge, 58 nmi.; convexity of right valve, 40 mm., concavity of left, 7 mm. Type specimens: Of vogdesi, No. 14, of heimi, No. 46, in the type collection at Stanford University ; of cataractes, in the British Museum ?. Type localities: Of vogdesi, Pleistocene, lumber yard, San Pedro; of heimi, southern part of Arroyo San Gregorio, Lower California, Pliocene; of cataractes, living, Gulf of California. Pliocene: 31st Street and Logan Avenue, San Diego (Sternberg Collection, 1924, specimen at Stanford University); San Diego Pliocene (Hemphill in Arnold, 1906); Cholas Valley, near San Diego (Steams in Arnold, 1906); type locality of heimi. Pleistocene: Type locality of vogdesi; Ventura Co. (Bowers in .\rnold); San Diego (Hemphill in Arnold); Lower California (Hertlein). Living: Gulf of California (Sowerby; Dall; .\rnold; etc.). Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 229 This species is distinguished from P. bellus and its varieties (hemphilli being the closest) by its greater convexity, by the beak projecting beyond the hinge, and by its larger size. Comparison of the types of heimi and of vogdesi show them to be exactly the same. The writers first thought that cataractes could be distinguished as a variety by the mid-ribs of the left valve and by the narrower ribs of the right ; but more specimens show that these distinctions will not hold. Pecten (Janira) hartmanni Hertlein Pecten (Pecten) harlrnanni Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, pi. 1, figs. 4, 6, 1925. Shell similar to that of P. vogdesi but still more convex and witli only 16-17 broad, rounding ribs; shell somewhat narrower. Type specimen: No. 48 in the type collection at Stanford University. Pliocene: Arroyo Mesquital, Lower California, lower Pliocene (?). Section Euvola Dall, 1898 Euvola Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 694, 1898. Type (by original designation), Ostrea ziczac Linnaeus, figured by Reeve, Conch. Icon., Vol. 8, Pecten, pi. 6, species 29, 1852, living, West Indies (according to Dall, which is probablj' correct) . Intermediate between Janira and Amusium, the shell with the arehed right valve and flat (or concave) left valve of Janira, but with the ribs practically obsolete on the exterior, and with well- developed internal lirae as in Amusium. Pecten (Janira) keepi Arnold Pecten (Pecten) keepi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 60, pi. 5, fig. 1, pi. 6, figs. 1, la, 1906. f Pecten (Pecten) refugioensis Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 7, pi. 1, fig. 2, pi. 5, fig. 9, 1925. Shell with the general form of P. vogdesi, but less convex and with the ribbing almost entirely obsolete; on the left valve ribs narrower than m vogdesi. and the somewhat broader interspaces bounded by narrow grooves so that the interspaces are sometimes hard to distinguish from the ribs; sometimes the sculpture so nearly obsolete that it can hardly be made out at all except on the umbones; shell internally grooved almost as in A77^^tsium. Dimensions: Altitude, 75 mm.; length, about 75 mm.; length of hinge, 35 mm.; convexity of right valve, 21 mm. Type specimens: Of keepi, No. 5, of refugioensis, No. 49, in the type collection at Stanford University. Type localities: Of keepi, Carrizo Creek district, north of the Mexican boundary, Imperial Co. ; of refugioensis, north of San Jose del Cabo, Lower California. Pliocene or upper Miocene: Type locality of refugioensis. Pliocene: Type locality of keepi. This species, as Hertlein has already pointed out, is a link midway between Janira (formerly known as typical Pecten) and Amusium. It is close to, and is probably directly related to P. ziczac (Linnaeus), a species living in the Caribbean region; but on the left valve of the latter the interspaces have been raised higher than the ribs (by contact with the internal grooves of the right valve), giving the sculpture a very peculiar appearance. The sculpture on the form refugioensis is a trifle weaker than that on the type of P. keepi; but as the two forms come from the same general region and have the same shape and the same sculpture pattern, the writers do not think the difference significant. A little more flattening of the right valve and bulging of the left would make this species an Amusium. 230 San Diego Society of Natural History [ Memoirs Subgenus; AMUSIUM Bolten, 1798 Amusium Bolten, Mus. Boltenianum, p. 165, 1798, original list includes Oslrea pleuronectes and others; Dall, Bull- Mus. Comp. Zool., Harvard CoUege, Vol. 12, p. 207, 1886; Trans. Wagner Free Inst. Sci., Phila., Vol. .3, p. 691 (last paragraph), pp. 693, 698, 744, 755, 1898. Amussium Bolten emended, Herrmannsen, Indicis Generum Malacozoorum, Vol. 1, p. 47, 1846. Type (by subsequent designation, Herrmannsen, 1846), Osti'ea pleuronectes Linnseus.^ Shell large, thin, almost flat, disc-hke, valves nearly smooth exteriorly, occasionally with faint radial grooves representing the edges of the obsolete ribs; internally with strong, narrow radial lirse, often in pairs corresponding to the edges of the interspaces of the ribbed ancestor, also a pair of short internal ridges diverging from the shallow resilial pit toward the side margins; ears small, short, shaped as in Janira, with a nearly obsolete byssal notch. Geologic range: Oligocene to Recent. Distribution: Mainly Oriental, but Dall reports also a typical species in the Gulf of Mexico. The transition from Janira to Amusium is very evident, being accomplished by the flattening of the right valve and the loss of the external ribs, with the compensating strengthening of the interior. The shape of the ears, as well as the existence of inter- mediate species, shows that Amusium is more closely allied to Janira than it is to any other group. Thus, although Pecten and Amusium have very dissimilar appearances, they are very closely allied genetically through Janira, and the writers are of the opinion that it would accomplish little to separate them generically, at least for the present. In other subgenera also, individual species have lost their external sculpture and de- veloped internal lirse instead, as P. pabloensis and P. hyalinus, derivatives from Aequi- pecten. The possibility of the transition may be seen in such forms as P. stearnsii variety hakeri, which has the general shape of Amusium but retains the external ribs and has not developed internal lirse. This form might be thought of as having gone a quarter of the distance from Pecten to Amusium. P. keepi has gone half the distance, retaining the arched right valve and flat left valve of Janira, but having lost external sculpture and developed internal lirse. P. laurentii has gone three-quarters of the distance, still having larger ears than typical Amusium and with the left valve almost flat but the right only slightly arched. Perhaps P. keepi has gone more than half way. Pecten (Amusium) laurentii (Gmelin) Oslrea laurentii Gmelin, in Linnaeus, Syst. Nat., Ed. 13, p. 3317, 1790. Peclen laurentii Gmelin, Sowerby, Thes. Conch., Vol. 1, p. 56, pi. 16, figs. 137, 138, 1842; Reeve, Conch. Icon., Vol. S, Pecten, pi. 16, species, 58, 1853. "Pecten (Amusium) lompocensis Arnold," Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 92, in part, not the type, pi. 28, fig. 3, 1906. ? "Pecten {Amusium) eondoui Hertlein," Hertlein, Bull. So. Calif. Acad. Sci., Vol. 24, p. 41, in part, unfigured paratype, 1925. Shell of medium size, thin, nearly smooth exteriorly, right valve slightly arched, left valve almost flat; with about twenty pairs of moderately strong internal lira?, the pairs in the right valve being very close together; hinge hne fully half as long as the shell, ears squarely terminated except the byssal ear, which has the byssal notch a little better developed than is usual for Amumum. Dimensions: Altitude, 84 mm.; length, 87 mm.; length of hinge, 45 mm.; diameter, 18 mm. Type locality: Living, China. * Schumacher, 1817, designates A. japonicum for Amusium Megerle von Miihtfeldt; but this change in type will not affect the use of Amusium, A. japonicum is included in Bolten's list. Volume I) PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 231 Miocene: Four miles south of Lonipoc, Santa Barbara County, California (Arnold) ; ? Montesano formation, upper Miocene, of Washington (Hertlein). Living: China. The ears, the internal ribbing, and the general shape of this species, which are all very characteristic, are shown in Arnold's figure of the California Miocene specimen. The writers feel that emphasizing the close relationship of the fossil to the living form is of much more significance than an attempt to separate them would be when no means are known by which to distinguish them. Pecten (Amusium) pleuronectes (Linnaeus) Ostrea pleuronectes Linnaeus, Syst. Nat., Ed. 10, p. 696, 1758. Pecten cristatus Bronn, Ital. Tert. Gebilde, p. 116, 1831. Pecten pleuronectes Linnaeus, Sowerby, Thes. Conch., Vol. 1, p. 55, pi. 16, figs. 127, 128, 1.35, 136, 1842; Reeve, Conch. Icon., Vol. 8, Pecten, pi. 13, species 48, 1853. Pecten (Amusium) lompocensis Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 92 in part, pi. 28, figs. 1, 2 (right valves), not fig. 3, 1906; Arnold and Anderson, Bull. 322 U. S. Geol. Survey, p. 32, pi. 18, figs. 2, 3, 1907. Shell of medium size, thin, nearly smooth externally, valves about equally convex; sculptured internally with 12 or 13 pairs of lirations, those in the right valve conspicuously paired, those in the left valve equally spaced so that the pairs are not evident ; ears about two-fifths the length of the shell, small, somewhat obliquely terminated, b.yssal notch almost obsolete. Dimensions: Altitude, 87 mm.; length, 87 mm.; length of hinge, 33 mm.; convexity of the two valves, 1(3 mm. Type s-pecimen: Of lompocensis, at the California Academy of Sciences (?). Type localities: Of pleuronectes, East Indies, living; of lompocensis, Miocene 4 miles south of Lompoc, Santa Barbara Co., Calif. Miocene: Lower Miocene between the Lower and Upper Ojai valleys, Ventura Co.; middle or upper Mio- cene (?), type locality of lompocensis; Italy (Bronn). Living: East Indies and China. The case of the synonymy of this species is just like the last. This species is dis- tinguished from laurentii by its fewer pairs of lirse (each pair representing an obsolete rib), by the greater distance between the lirse in each pair, and by the smaller ears. Pecten (Amusium) japonicus (Gmelin) Ostrea japonica Gmelin, in Linnaeus Syst. Nat., Ed. 13, p. 3317, 1790. Pecten japonicus Gmelin, Sowerby, Thes. Conch., Vol. 1, p. 55, pi. 15, figs. 109, 110, 1842; Reeve, Conch. Icon., Vol. 8, Pecten, pi. 12, species 47, 1852. ? Pccteii morloni Ravenel, Proc. Acad. Nat. Sci., Phila., Vol. 2, p. 96, 1844; Tuomey and Holmes, Pleiocene Fossils of South Carolina, p. 27, pi. 10, figs. 1, 2, 1855. ? "Amusium pleuronectes Linnaeus," Dall, Bull. Mus. Comp. Zool., Harvard College, Vol. 12, pp. 208, 209, 1886; Vol. 18, p. 438, 1889. ? Pecten {Amusium) mortoni Ravenel, Glenn, Maryland Geol. Survey, Miocene Volume, p. 372, pi. 99, fig. 1, 1904. Shell Kke that of pleuronectes but larger and with 18 to 24 pairs of internal lirae in each valve, the pairmg not very distinct. Dimensions: Altitude 110 mm.; length, 112 mm.; length of hinge, 39 mm.; convexity of right valve, 12 mm., of left valve, 9 mm. f Miocene: Atlantic states (as mortoni). Living: Japan; ? Gulf of Mexico (as mortoni). Again we have two forms apparently the same in widely different localities. There can be no question but that the stock migrated between the two localities in the Miocene, passing probably through California; and if the species remained unchanged from the Miocene to the Recent in the Atlantic, there is no reason why it could not do the same in the Pacific. 232 San Diego Society of Natural History [ Memoirs Pecten (Amusium) condoni Hertlein Peclen (Amusium) condoni Hertlein, Bull. So. Calif. Acad. Sci., Vol. 24, p. 41, pi. 4, figs. 8, 9, 1925. Shell with the shape and size of pleuronectes, but showing on the surface apparently 17-18, very nearly obsolete, low, broad ribs, and with a byssal notch about as strong as that of laurentii; interior not known. Dimensions: Altitude, 72 mm.; length, 72 mm.; length of hinge, 29 mm.; convexity of the two valves, 20 mm. (half m each ) . Type specimen: No. 15 in the type collection at Stanford University. U. Miocene: Montesano formation, Washington. As species of this subgenus are distinguished principally by their interior ribbing, the status of this form is uncertain. It may be the same as pleuronectes, or possibly P. obliteratus (Linnaeus) ' from West Australia and China. Subgenus PROPEAMUSSIUM de Gregorio, 1884 Propeamvssium de Gregorio, "Nota intorno ad Alcune Nuove Conchiglie Miocenische di SicUia," II NaturaUsta Siciliano, Anno 3, no. 4, p. 119, January 1, 1884; Fischer, Man. Conchyl., p. 944, 1886, though the type cited, Pecten iniequisadplus Tiberi, is not in de Gregorio's original list; Stewart, Special Publ. No. 3, Acad. Nat. Sci. PhDa., p. 122, 1930. Propeamusium de Gregorio em., Dall, Bull. Mus. Comp. Zool., Harvard College, Vol. 12, p. 210, 1886; Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 698, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 50, 1906, type stated in all three references, P. insequisculptus Tiberi = fenesiratus Forbes. Yariamussium Sacco, Boll. Mus. Zool. ed Anat. Comp., R. Univ. Stud. Torino, Vol. 12, p. 101, June 11, 1897; I MoUuschi dei Terreni Terziarii del Piemonte e della Liguria, Pt. 24, p. 49, 1897, type (by monotypy ?) Peclen cancellalus Schmidt, not Phillips, 1829, nor Goldfuss, 1833, nor Hall, 1843; Dautzenberg, Res. Camp. Sci. Albert I, Prince de Monaco, Vol. 72, p. 271, 1927. Not "Propeamussium de Gregorio," Cossmann and Peyrot, Actes de la Societe Linneenne de Bordeaux, Vol. 66, "Conchologie Neogfoique de I'Aquitaine," Vol. 2, p. 305, August, 1914; Woodring, Carnegie Inst. Wash., Publ. No. 366, p. 74, 1925. Type (by monotypy), Pecten {Propeamussium) cecilice de Gregorio, "Miocene" of Sicily. Shell small, very thin, valves of approximately equal convexity, sculptured externally with concentric Imes and sometunes on the left valve with radial striations, iiaternally with a moderate number of raised liriB that m adult specimens often do not reach the periphery ; hinge line of variable length, byssal ear sometimes with radial riblets, byssal notch moderately deep, narrow. Geologic range: Cretaceous to Recent. Distribution: Deep water, normally, but sometimes found in shallow; widely dis- tributed. It is unlikely that Propeamussium has any particular relation with Amusium. The byssal notch shows that it is probably more directly connected with Chlamys or Aeqtii- pecten. Stewart has pointed out that Cossmann and Peyrot and later Woodring have raised the question of whether P. cecilicB has the internal lirse of this group or not. However, Stewart concluded from a study of the original description that cecilice does have the in- ternal lirse, and the present writers are inclined to believe that this view is correct. De Gregorio mentions nine broad, red-colored rays, presumably on the exterior. It seems hardly possible that the red color is the original color of the shell, if the Miocene age is 1 Ostrea obliterata Linnaeus. Syst. Nat., Ed. 10, p. 697, 1758. Pecten obliteratus Linnteus, Son-erby. Thes. Conch., Vol. 1, p. 55, pi. 16, fig. 126, 1S42; Reeve, Conch. Icon., Vol. 8, Pecten. pi. 19, species 70, 1853. Volume 1 ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 233 correct. It is more probable that the shell had been stained by secondary oxide of iron, the stain affecting perhaps the parts of the surface that had once been ribs in an ancestral Peclen. If this is the case, these rays should be bordered by about 18 internal lirations of the sort described by de Gregorio (like so many thin, delicate sticks) in the interior of the shell. Propeamussiuvi may be more closely allied to ribbed forms, like Pecten pablo- ensis or perhaps a Janira, than it is to Pseiidamussiu77}. For the sake of those who may find it difficult to consult the original reference to Propeamussium, a translation of de Gregorio's original description is given here in full: Note on Some New Miocene Shells from Sicily :ti * dl: * * Propeamussium, new subgenus. I am proposing this subgenus for the species described below. Perhaps P. semi- rndialus and xinguiculus Mayer (in HoiTmann), etc., should also be referred to it. Pecten {Propeamussium) ceciUx de Gregorio. Shell extremely thin and compressed; with its internal and external surface polished. Diameter, 3.5 mm.; depth, 4 mm. The sculpture consists of very fine linear threads, concentric and radial; in the peripheral region these threads are almost completely cancellate, though some of the concentric lines are difficult to distinguish from lines of growth. The radial threads are distinct in the umbonal region. — More char- acteristic of this species are about 9 blood-colored red rays, rather wide, almost as wide as the interspaces. These rays do not project at all from the exterior, nor from the interior either, it would seem, if part of the umbonal region is, perchance, left out of consideration. — They are neither costse nor mere colored zones; they affect the internal structure (cut the internal structure into strips) and they can be separated from the rest of the shell like so many thin, delicate sticks. The right valve is barely convex, almost flat; the rays, though transparent, are firmly fixed to the inner part; they are to be found in the umbonal region and go as far as the middle, but without completely crossing it. The left valve is even flatter; in fact, it is hardly at all convex in the umbonal region, and as for the rest, it is even a little concave, but that perhaps is due to the compression undergone during fossilization. The rays are much more marked and visible; they traverse not only the umbonal region, but also the middle. It much resembles Amussiuvi hicidum Jeffreys, from which it is distinguished by the colored zones and by the diverse sculpture, principally by the radiating threads. My guide, V. Meneguzzo, found various fragments of this most interesting species and one specimen (though lacking the ears) in the Terrebianche region in a white foraminiferal marl which appears to me much like the one at Malta. ***** P.\LERMo, December, 18S.3. Section Propeamussium, s. s. Shell with stronger radial sculpture on the exterior of the left valve, making the two valves noticeabl.v discrepant, rarely with some radial striation on the exterior of the right valve also. The species of this section from the Pacific coast of North America are very like species from other parts of the world, and in time some of them will probably be found to be conspecific. There are several species in the early Tertiary of the Pacific coast that should be assigned here. P. (Propeamussium) interradiatus Gabb is said to have come from the Eocene, though there is some reason to believe now that the type locality might have been in the Kreyenhagen shale, Oligocene. This species is large, having an altitude of 25 mm., the eight internal lirse of the left valve continuing only about half that distance; the ears are large, and the left valve has numerous radial striations. P. (Propeamussium) icaylandi Arnold from the Clallam formation, middle Miocene of Washington and its probable synonym P. stanfordensis Arnold from the Miocene near Stanford University, middle California, are much like the young of interradiatus and may be found to be con- specific with that species also. They are distinguished only by smaller size and shorter hinge line. The "elevated ridges on the left valve" of waylandi look very much like the impressions of the internal ribbing and can be attributed to the state of preservation. P. [Propeamussium) claUamensis Arnold, which occurs with ivaylandi, is distinguished by the fewer, coarsely laminated radial ribs on the exterior of the left valve. All of these forms are figured and described by Arnold in his Pecten monograph, 1906. 234 San Diego Socikty of Natural History [ Memoirs Pecten (Propeamussium) alaskensis Dall Pecien (Pseudamusiutn ?) alaskensis Dall, Amer. Journ. Couch., Vol. 7, p. 155, pi. 16, fig. 4, 1871. Pecten [Propeamusium) alaskensis Dall, Bull. Mus. Comp. Zool., Harvard College, Vol. 12, p. 215, pi. 5, figs. 7, 7((, 1886; Bull. 37 U. S. Nat. Mus., pi. 5, figs. 7, 7a, 1889, 1903; Trans. Wagner Free Inst. Sci., PhUa., Vol. 3, p. 711, 1898; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 133, pi. 53, figs. 2, 2a, 3, 1906; DaO, Bull. 112 U. S. Nat. Mus., p. 20, pi. 1, fig. 2, 1921; Oldroyd, Univ. Wash. Publ., Puget Sound Biol. Sta., Vol. 4, p. 20, pi. 27, fig. 6, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 62, pi. 12, fig. 3, pi. 38, fig. 6, 1924. Not "Pecten alaskensis Dall," Whiteaves, Trans. Roy. Soc. Canada, Vol. 4, p. 119, 1S87, = P. vancouverensis Whiteaves. Pecten alaskensis DaU, Kiister and Kobelt, Martini-Chemnitz Syst. Conch. Cab., Ser. 2, Vol. 17, Spondylus und Pecten, p. 245, pi. 64, figs. 7, 8, 1888; Newcombe, Bull. Nat. Hist. Soc. Brit. Columbia, p. 53, 1893. Pecten (Propeamusium) riversi Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 126, pi. 44, figs. 8, 9, 1906. Pecien {Propeamusium) lens Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 56, pi. 2, figs. 2a-d, 1916, not Pecten Isevis Pennant, 1777, nor Defrance, 1825, nor Nilsson, 1827, nor Potiez and Michaud, 1844, etc. Pecten calamitus Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 176, 1924, new name for Pecten levis Moody. Shell small, thin, circular, with a short hinge line, right valve smooth externally except for growth Imes, left valve sculptured with 18 or more fairly strong prunary radial riblets and about as many more smaller intercalaries, the ribs fuiely laminated on specimens tliat have not lost the surface layer of the shell; interior of each valve with about 22 radiating lira;, which in the right valve are covered up from the center of the shell to the uml)o by a deposit of chalky material, Init which per- sist faintly to tlie uml^o m the left valve if the chalky deposit has been worn o(i, tliough they are difficult to distinguish from the impressions of the external ribs, the number of the mternal lirse often mcreased to 29-33 by the appearance of intercalaries in the widest interspaces. Dimensions: Altitude, 17 mm.; length, 18 mm.; length of hinge, about 9 mm.; convexity of the two valves, 4 mm., the left slightly the more convex. Type specimens: Of alaskensis, in the U. S. National Museum; of riversi, No. 33 in the type collection of Stanford University; of calamitus, No. 11,084 at the University of' California. Type localities: Of alaskensis, living, Alaska; of riversi, Santa Monica Canyon, Los Angeles Co.; of calamitus, Fourth and Broadway, Los Angeles. Pliocene: Type locality of calamitus. Pliocene or Pleistocene: Type locality of riversi. Pleistocene: Lower San Pedro series of Deadman Island, San Pedro Harbor, Los Angeles Co. (Arnold); of Alaska (Dall); of Vancouver Island (Newcombe). hiving: Alaska to Magdalena Bay, Lower California, usually in deep water; Japan. This species is easily distinguishable from the Miocene and older species on the Pacific coast by its more numerous internal lirations. The writers tried to distinguish riversi from the living P. alaskensis Dall on the basis of the still more numerous internal lirations on the living specimens, until they noticed that Dall's original description calls for only 21. The form renamed by Hanna is exactly like rii^ersi. P. [Propeamussium) davidsoni Dall, a species living in Alaska, and apparently to be assigned to Propeamussium rather than to Pseudamussium, has much the same shape; but it has fewer and stronger external ribs on the left valve, and after it is a little more than half grown it develops ribs on the outside of the right valve also.^ Section Parvamussium Sacco, 1897 Parvamussium Sacco, Boll. Mus. Zool. ed. Anat. Comp., R. Univ. Stud. Torino, Vol. 12, p. 101, June 11, 1897; I. MoUuschi del Terreni Terziarii del Piemonte e deUa Liguria, Pt. 24, p. 48, 1897; Woodring, Carnegie Inst. Wash., Publ. No. 366, p. 74, 1925. I Pecten davidsoni Dall, Nautilus, Vol. 11, p. 86, 1897; Proc. V. S. Nat. Mus., Vol. 24, p. 559, pi. 40, figs. 5, 6, 1902: Keep, West. .\mer. Shells, p. 41, figs. 21o, 216, 1904. Pecien (.Pseudamusium) danidsoni Dall, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 13S, pi. 50, figs. 4, 4a, 1906: Dall, Bull. 112 U. S. Nat. Mus., p. 20, 1921: Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 61, 1924. Pecten (Propeamusium) davidsoni Dall, Moody, loc. cit. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 235 Type (by original designation), Pecten duodecim-lamellatus Bronn, Italiens Tertiiir Gebilde, p. 116, 1831, Miocene of Ta])])iano, Italy. The original description of this species is: "P. testa subcequivalvis compressa, rotundata, eleganter et dense concentrice-striata, eradiata; auriculis cequalibus; intus lamellis 11-12, oeque-distantibus, apice clavato-incras- saiis radiata. "Verwandt mit P. squamula Lmk. VI. i. 83. Liinge und Breite 7'"." Without or with very weak radial striations on the exterior of the left valve. Geologic range: Miocene of the West Indies (Woodring) to Recent. Distribution: Deep water, typically, but sometimes found in shallow; widely dis- tributed. This section is closely related to the typical, there being intimate gradations between them. If Propeamussium should in any way be invalidated, Parvamussium would be- come the subgenus or genus and Variamussium would be a section. Subgenus PSEUDAMUSSIUM Klein in Morch, 18.53 Pseudamusium Klein, Meth. Ostrac, p. 1.34, 1753 (pre-Linnsean), species included, Pecten Isevis variegatus, etc. Pseudamussium Klein, Morch, Cat. Conch. Yoldi, Pt. 2, p. .59, 18.53, original list includes Pecten seplemradiatum Muller, under which is placed "P. pseudamussium Ch." as a synonym; H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 553, 1858, original list contains liybridus Gmelin and a number of others, but exnticus Cheronitz and lasvis Idein and pseudamusium Sowerby not mentioned by name; Stohczka, Mem. Geol. Survey, India, Palaeo. Indica., Vol. 3, p. 426, 1871, type designated : "Pecten exoticus Chenmitz {Pseudamusimn-Pecten Isevis etc., of Klein)." "Propeamussium de Gregorio," Cossmann and Peyrot; Woodring; etc.; see Propeamnssiuju. Pseudamusium H. and A. Adams, DaU, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 697, 1898. Type (by tautonymy, and by subsequent designation, Stoliczka 1871), Ostrea hybrida Gmelin, in Linnaeus, Syst. Nat., Ed. 13, p. 3318, 1790; + Pseudamusium, Pecten Icevis, etc., Klein, Meth. Ostrac, p. 134, 1. 9, fig. 31, 1753; " Pseud- Amusium. Pecten loevis," etc., Klein cited by Chemnitz, Neues Syst. Conch. Cab., Vol. 7, p. 298, but not pi. 63, figs. 601, 602, 1784; -|- Pecten exoticus Chemnitz, Vol. 11, p. 262, pi. 207, figs. 2037, 2038, 1795; + Pecten pseudamusiuyn Sowerby, Thes. Conch., Vol. 1, p. 56, pi. 19, figs. 211, 212, pi. 20, fig. 243, 1842, also illustrated by Reeve, Conch. Icon., Vol. 8, Pecten, pi. 16, species 56, 1853. Shell small, very thm, discoidal; sculptured with fine radial and concentric striations, sometimes with only the radial on the left valve and only the concentric on the right, when these lines are worn off showing only concentric waves ; huige line rather long, byssal ear sculptured with radial riblets, byssal notch deep; interior smooth. Geologic range: Cretaceous to Recent (if Camptonectes is included, Jurassic to Recent). Distribution: Practically world wide, more characteristic of deep water, but also found in shallow. This subgenus looks very much like a primitive form that has lived on for a long time without changing much. It resembles somewhat the Palaeozoic genus Aviculopecten, and it may be related to Chlamys and the other modern Pectens as an ancestor. It is distin- guished from Propeamussium by its smooth interior. Some of the names that have been applied to closely related groups, a number of which should probably be considered synonyms or should be assigned to subordinate divisions, are: Camptonectes Agassiz in Meek, 1864, Syncyclonema Meek, Eburneopecten Conrad, 1865, Pectinella, Hyalopecten, 236 San Diego Society of Natural History [ Memoirs Cyclopecten, Verrill, 1897, and possibly Palliolum Monterosato, 1884, and Lissochlamyn. Sacco, 1897. Dall and others have stated that Klein had but a single species. The references by Morch and by H. and A. Adams to Klein should make Klein's species available for type, no matter whether Pseudamussium is dated from Morch or from the Adams brothers. Hence Woodring's objection' that Pecten exoticus Chemnitz and Peden pseuda- musium Sowerby are not named in the original list does not invalidate Stoliczka's desig- nation, and we do not have to rely on Suter's designation in 1913 of Pecten hybridus (Gmelin), which would not be available for Pse^idamussium Morch. However, Stewart has pointed out= that Morch cited under "Pecten septemradiatum Miiller" "P. pseuda- mussium Ch." If Pecten septemradiatus Miiller is taken as the type by absolute tautonymy, then Pseudamussium Morch will have to be applied to Peplum and one of the other names noted above will have to be applied to this group, unless an earlier binomial use of Pseudamussium can be found. Stewart uses Palliolum and proposes a new subgenus, Delectopecten, for Vancouver ensis. On the other hand, if "P. pseudamussium Ch." determines Morch's idea of the type of Pseudamussium by absolute tautonymy (as it clearly must), then Pecten psetidamusium Chemnitz must be taken into account as part of Morch's type, if not the whole of it. Chemnitz' species is composite, for the reference to Klein clearly includes Klein's species, although the figures are apparently of septemradiatus. Hence the type of Pseudanmssium as determined by tautonymy must be considered composite, and Stoliczka, being the first definitely to designate the type, fixed the name on Klein's species. It is clear that the early writers confused the two groups, and we have no right to say that Morch meant to apply Pseudarnussium exclusively to the septemradiatus group, in view of his reference to Klein. Although there is some question about whether this reasoning can be accepted, or must be accepted, or not, the rule is that in doubtful cases the long-established usage should be followed. Furthermore, Stoliczka's designation would probably apply to any earlier binomial use of Klein's name that may be found, and the present course would, in case such a use is found, avoid the necessity of changing the meaning of the name and later shifting it back again to its original meaning. The finding of an earlier binomial use is not at all unlikely, because Klein's names were well known among the early conchologists and many early sources, especially German and Italian, have not been investigated. Deshayes almost established the name,^ but invalidated his application of it by stating that it was not adopted. Pecten (Pseudamussium) pedroanus (Trask) Plagiosloma pedroana Trask, Proc. Calif. Acad. Sci., Vol. 1, p. 93, pi. 3, figs. 1, la, 1856. Plagioslovm Iruncala Trask, Proc. Calif. Acad. Sci., Vol. 1, p. 94, pi. 3, fig. 3, 18.56. Plagiosloma annulalus Trask, Proc. Calif. Acad. Sci., Vol. 1, p. 94, pi. 3, fig. 2, 1856. Pecten peckhami Gabb, Geol. Survey Calif., Palaeo, Vol. 2, p. 59, pi. 16, figs. 19, 19a, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 258, 1888; DaU, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 705, 1898; ? Arnold. Bull. 396 U. S. Geol. Survey, p. 13, pi. 3, figs. 2, 2a, Jan. 15, 1910, reprinted in Bull. 398, pi. 25, figs. 2, 2a, 1910; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. Peclen pedroanus Trask, Gabb, Geol. Survey Calif., Pateo., Vol. 2, p. 60, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 258, 1888; Dall, Trans. Wagner Free Inst. Sci., Phila., Vol. 3, p. 705, 1898; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907. 1 Woodring, Carnegie Inst. Wash., Publ. No. 366, p. 72, 1925. 2 Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 122, 1930. « Deshayes, Ency. Mfth., Vol. 3, p. 854, 1S32. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 237 Pecten randolphi Dall, Nautilus, Vol. 11, p. 86, 1897; Proc. U. S. Nat. Mus., Vol. 24, p. 559, pi. 40, fig. 2, 1902; Keep, West Amer. SheUs, p. 41, 1904. Pecten {Pseudamusium) peckhami Gabb, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 56, pi. 3, figs. 6, 7, 8, 1906; Proc. U. S. Nat. Mus., Vol. 32, pi. 44, fig. 3, 1907; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pi. 31, fig. 3, 1907; Dall, Prof. Paper 59 U. S. Geol. Survey, p. 113, 1909. Pecten {Pseiidanmsiwn) pedroanus Trask, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 90, pi. 28, figs. 4, 5, 1906; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pi. 36, figs. 5, 6, 1907. Pecten (Pseudamusium) randolphi Dall, Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 138, pi. 48, figs. 2, 2a, 1906; Dall, Bull. 112 U. S. Nat. Mus., p. 19, 1921; Oldroyd, Univ. Wash. Publ., Puget Sound Biol. Sta., Vol. 4, p. 19, pi. 4, fig. 8, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 59 (not pi. 14, figs. 5, 6 = P. (Propmmussium) dav-idsoni), 1924. Pecten {Pseudamusium) randolphi Dall var. tillamookensis Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 139, pi. 48, figs. 3, 3a, 1906. Pecten pedroanus Arnold, McLaughlin and Waring, Map Folio accompanying Bull. 69 Calif. St. Mining Bureau, pi. 1, fig. 35, 1914. Pecten {Pseudamusium) tillamookensis Arnold, Dall, Bull. 112 U. S. Nat. Mus., p. 20, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 59, 1924. ? Pecten vanwinkleie Clark, Univ. Calif. Publ. Geol., Vol. 15, p. 82, pi. 15, fig. 2, 1925. Shell small, transparent, discoidal, both valves sculptured with delicate radial striations and con- centric lines that become slightly spinose at the intersections but are often entirely worn or dissolved off so that the surface of the shell is varied only by broad concentric waves; hinge line of variable length, the byssal ear 'sculptured with four or five fairly strong radial riblets, byssal notch moderately deep, leaving a scar about two-thirds as wide as the rest of the ear. Dimensions (of a large hvuig specimen): Altitude, 30 mm.; length, 30 mm.; length of hinge, 14 mm.; convexity of the two valves, 6 mm. Type specimens: Of randolphi, No. 107,749, of tillamookensis, No. 150,233, in the U. S. National Museum. Type localities: Of pedroanus, truncatus, and annulatus in the shales underlying the "Pliocene" and Pleistocene of San Pedro, probably Pliocene; of peckhami, in the bitum- inous shales probably of the Monterey formation, middle Miocene, of Sulphur Mt. south of the Ojai Valley, Ventura Co.; of randolphi, living off Destruction Island, Washington, in 516 fathoms; of tillamookensis, living off Tillamook Bay, Oregon, in 786 fathoms; of vanwinklece, Oligocene of Porter Creek, Washington. ? Eocene: Tejon formation of the Coalinga district (Arnold, 1910). f Oligocene: As P. vanxnnklese. Miocene: Numerous localities, especially in the middle Miocene, the Monterey shale of California and the Clallam formation of Washington (Arnold, 1906). Pliocene: Type locality of pedroanus; Puente Hills, Los Angeles Co. (Arnold); Third Street tunnel, Los An- geles, abundant (Arnold, 1907); near Eastlake Park, Los Angeles (McLaughlin and Waring). hiving: Bering Sea to Guaymas, Mexico (DaU, 1921). The synonymy listed above is just another case of putting together closely related forms that exhibit no significant characters by which they can be separated. Attempts have been made to point out distinguishing characters, but the writers have seen noth- ing that did not appear to be due to individual variation or to the state of preservation (even in Recent forms the differences in preservation give individuals different appear- ances). There is little use in keeping forms separate until it is known how to separate them. If such forms are synonymized, there will be fewer workers misled into trying to use them as guide fossils. Variety pedroanus, s. s. Byssal ear comparatively narrow. 238 San Diego Society of Natural History [ Memoirs Pecten (Pseudamussium) pedroanus (Trask) variety vancouverensis Whiteaves "Peden caurinus Gould young," Dall, Bull. Mus. Comp. Zool., Harvard CoU., Vol. 12, p. 216, pi. 5, fig. 4, 1886, figure reprinted in Bull. 37 U. S. Nat. Mus., pi. 5, fig. 4, 1889, 1903. "Pecten {Pseudamusium) alaskensis Dall," Whiteaves, Trans. Roy. Soc. Canada, Vol. 4, p. 119, 1887. Pecten (Pseudamusium) vancouverensis Whiteaves, Ottawa Naturalist, Vol. 7 (Trans. Ottawa Field-Nat. Club, Vol. 9), p. 133, pi. 1, figs. 1, la, 1893; Newcombe, Bull. Nat. Hist. Soc. Brit. Columbia, p. 53, 1893; Taylor, Trans. Roy. Soc. Canada, Ser. 2, Vol. 1, p. 26, 1895; Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 140, pi. 52, figs. 3, 3a, 1906; DaU, Bull. 112 U. S. Nat. Mus., p. 20, pi. 1, figs. 4, 5, 1921; Oldroyd, Univ. Wash. Publ., Puget Sound Biol. Sta., Vol. 4, p. 20, pi. 4, fig. 7 (not fig. 8), 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 60, pi. 12, figs. 6, 7, 1924. Pecten (Pseudamusium) arces DaU, Proc. U. S. Nat. Mus., Vol. 45, p. 592, 1913. Pecten (Pseudamusium) vancouverensis fernandoensis Hertlein, Bull. So. Calif. Acad. Sci., Vol. 24, pi. 4, figs. 6, 7, 1925. Like the typical variety but with the ventral submargin of the right valve sloping off more ab- ruptly in a concave arc, leaving more room for the byssal notch and the broader byssal ear; the ven- tral ear of the left valve correspondingly deeper. Type specimens: Of vancouverensis, at Ottawa (?); of arces, No. 267,169 in the U. S. National Museum; of fernandoensis, No. 16 in the type collection at Stanford University. Type localities: Of vancouverensis, living off Vancouver Island; of arces, off Santa Barbara in 500 fathoms; oi fernandoensis, on the Ventura River IJ^ mi. north of Ventura, 34 mi. south of Taylor well No. 1, Ventura Co., Calif. Pliocene: Type locality oi fernandoensis; also from well core, Long Beach, Calif. (Hertlein). lAving: Bering Sea to San Diego. This variety is distinguished from the typical by its larger byssal ear. In the speci- mens from the Pliocene the distinction is not very definite, and it is probable that the variety first appeared at about the beginning of the Pliocene. The form described by Clark and Arnold as variety sanjuanensis^ from the Sooke beds, lower Miocene or Oligo- cene of Vancouver Island, appears to be a Propeamussium close to alaskensis and may extend the range of that species into the older Tertiary. P. lompicoensis Arnold- (not to be confused with lompocensis) is another form assigned to Pseudarmissium that is more probably a Propeamussium, though it is poorly preserved and it is difficult to be sure. The latter appears to belong to the P. interradiatus group, and it may be a synonym of that species. Dall has described, but not figured, two other supposed species of Pseudamussium from San Diego. ^ Another supposed species described by Dall was renamed binominatus by Hanna.^ Family LIMIDAE Shell equivalve, auriculate, gapmg, Pectiniform, with one adductor muscle; shell substance fibrous, with minute tubules, not pearly or prismatic; hmge without teeth, or \a ith traces of taxodont armature; hmge area extendmg on both sides of beaks, equal in botli valves; ligament external, resihum sub-mternal; byssus generally present. (After Dall.) Geologic range: Carboniferous to Recent. Distribution: World wide. 1 Fecten (Pseudamusium) vancouverensis Whiteaves subspecies sanjuanensis Clark and Arnold, Univ. Calif. Publ. Geol., Vol. 14, p. 140, pi. 16, figs. 5. 6, 192.3, type specimen No. 224 at Stanford University. - Pecten {Pseudamusium) lompicoensis Arnold, Prof. Paper 47 U. S. Geol. Survey, p. 89. pi. 23, fig. 5, pi. 27, fig. S, 1906. 3 Pseudamusium incongmum Dall, Pseudamusium bistriatum Dall, Proc. U. S. Nat. Mus., Vol. 52, pp. 403, 404, 1916. * Pecten (Pseudamusium) andersoni Dall, Sci. Res. Canadian .\rctic Exped., Vol. 8, p. 19A, pi. 2, figs. 7, 8, 1918, not Pecten (Aequipecten) andersoni Arnold, 1906. Pecten binominatus Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 175, 1924. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 239 Genus LIMA Bruguiere, 1797 Lima Brugiere, Encycl. Meth. (Tabl. Vers), pi. 206, 1797, name and figure only; Cuvier, Tabl. El^m. Hist. Nat. Anim., p. 421, 1798; Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 88, 1799; Harris, Cat. Tert. Moll. Brit. Mus., Pt. 1, p. 309, 1897: Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 765, 1898; Woodring, Carnegie Inst., Publ. No. 366, p. 79, 1925. Type (by absolute tautonymy, Cuvier, 1798), Ostrea lima Linnseus, Syst. Nat., Ed. 10, p. 699, 1758; figured by Bruguiere in the Ency. Meth., pi. 206, fig. 4, 1797, and described by Deshayes in Ency. Meth., Vol. 3, p. 345, 1832; also figured by Sowerby in Reeve's Conch. Icon., Vol. 18, Lima, sp. 10, pi. 2, fig. 10, 1872, as L. squamosa Lamarck, Indo-Pacific, Recent. Shell equivalve, compressed, ovate, oblique, slightly mflated; ornamented with radiating costse, which may be simple or scaly; umbones prominent, auriculate, small lateral appendages unequal; carduial area triangular, havmg a central pit for the ligament; hinge without teeth; muscle impres- sions large. (Harris.) This genus is abundantly represented in the Mesozoic. Several species have been reported from the early Tertiary of the Pacific coast and three in the Pliocene and Pleisto- cene deposits. Lima tetrica ( ioukl Lima telrica Gould, Proc. Boston Soc. Nat. Hist., Vol. 4, p. 93, 1851; Boston Jour. Nat. Hist., Vol. 6, p. 405, pi. 16, fig. 6, 1857; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, pp. 535, 583, 621, 1863. Radula tetrica Gould, Lamy, Jour, de Conchyl., Vol. 57, p. 214, 1909. Type locality: La Paz, Gulf of California, Mexico. Pleistocene: Upper Pleistocene of coast of Oaxaca, Me.xieo (coll. by R. H. Palmer). Recent: Lower California to Panama, Galapagos and Juan Fernandez Islands. This is a small, moderately oblique species which appears to be related to L. angulata Sowerby. 1 Lima dehiscens Conrad Lima dehiscens Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 247, pi. 19, fig. 7, 1837; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 245, 1888; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 769, 1898; Dall, in Orcutt, West American Scientist, Vol. 19, No. 3,^ p. 23, 1921. "Lima orientalis Adams and Reeve," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 645, 1864; Keep, West Coast Shells, p. 168, fig. 142, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 1.5, p. 193, 1892; not of Adams and Reeve, fide Arnold, 1903. Lima {Mantellum) dehiscens Conrad, Dall, U. S. Nat. Mus., Bull. 112, p. 20, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 63, 1924. Pliocene: Santa Barbara (Cooper). Pleistocene: Lower San Pedro series of Deadman Island, one specimen (Arnold); upper Pleistocene of San Quintia Bay, Lower California, Mexico (Dall, in Orcutt). Recent: Monterey, California, to Acapulco, Mexico (Dall, 1921). Lima hamlini Dall Lima hamlini Dall, Nautilus, Vol. 14, p. 16, 1900; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; Dall, Vol. 66, .■^t. 17, p. 18, pi. 29, fig. 6, 1925. Type locality: Third Street tunnel, Los Angeles; Pliocene. Pliocene: Pliocene clays of Los Angeles City (Dall; Arnold). The single imperfect specimen is well figured by Dall (1925). ' Thes. Conch., Lima, sp. 12, figs. 39. 40. 1843; Conch. Icon., Vol. 18, Lima, sp. 13, pi. 3, fig. 13, 1872. ' Vol. 19, No. 3, is dated June 15, 1921; Vol. 21 is dated 1919! 240 San Diego Society of Natural History [ Memoirs Superfamily Anomiacea Family ANOMIIDAE Shell variable, often rather flat, sometimes pearly and thin; in most genera the right valve with a foramen, through which passes the calcified or homy plug ; resilium internal ; hinge usually edentu- lous or rugose. Genus ANOMIA Linnaeus, 1758 Anomia Linnaus, Syst. Nat., Ed. 10, p. 700, 175S; Children, Quart. Jour. Sci., Lit., Arts, p. 46 (pi. 2, fig. 97), April, 1823; Meek, U. S. Geol. Surv. Territories, Vol. 9, p. 21, 1876; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 774, 781, 1898. Type (by subsequent designation, Children, 1823), Anomia ephippium LinniBus, Syst. Nat., Ed. 10, p. 701, 1758. Shell thin, attached, with a calcified byssal plug passing through a sinus in the right valve; two byssal scars present; hinge edentulous. Geologic range: Jurassic to Recent (Meek). Distribution: Cosmopolitan. Pododesmus differs in having a single conspicuous byssal scar. Placunanomia is large, heavy shelled, its byssal foramen is entirely closed except in the young, and its hinge is armed. Anomia peruviana d'Orbigny Plate' 12, Figures 2, 5 Anomia peruviana d'Orbigny, Voy. Amer. M&id., Vol. 5, pt. 3, Moll., p. 673, 1846; Philippi, Abbild. Beschreib. Conchyl., Vol. 3, p. 131, pi. 1, fig. 2, 1850; DaU, Proc. U. S. Nat. Mus., Vol. 37, pp. 148, 257, pi. 28, fig. 4, 1909; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 26, pi. 3, fig. 3, 1920; DaU, Bull. 112 V. S. Nat. Mus., p. 21, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 65, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; E. K. Jordan and Hertlein, p. 417, 1926; Waterfall, Univ . Calif. Publ. Geol., Vol. 18, p. 78, 1929. Anomia lampe Gray, Proc. Zool. Soc. London for Jan.-June, 1850, p. 117; Reeve, Conch. Icon., Vol. 11, Anomia, pi. 4, figs. 16a-fc, 1859; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Museum, p. 167, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, p. 646, 1864; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 106, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 229, 1888; Keep, West Coast Shells, p. 163, 1888, 1892; William.son, Proc. U. S. Nat. Mus., Vol. 15, p. 194, 1892; DaU, Trans. Wagner Inst. Sci., Vol. 3, p. 785, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 117, 1903; Lamy, Journ. Conchyl., Vol. 57, pp. 224, 225, 1909. Anomia limaiula Dall, Proc. U. S. Nat. Mus., Vol. 1, p. 15, 1879; Trans. Wagner Inst. Sci., Vol. 3, p. 785, pi. 35, fig. 19, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 118, 1903. Anomia simplex MabiUe, Bull. Soc. Philom., Paris, Ser. 8, Vol. 7, p. 73. 1895. Pliocene: Turtle Bay, Lower California, Mexico (Jordan and Hertlein). Pleistocene: Lower San Pedro series of Deadman Island and San Pedro, "rare"; common in upper San Pedro series of San Pedro, Los Cerritos (Signal Hill), Long Beach, and Crawfish George's; Pleistocene of Barlow's Ranch, near Ventura, and of Spanish Bight and Pacific Beach, San Diego (Arnold, as A. lampe); Pleistocene of Coronado Beach (DaU, 1879, as ^4. limaiula); Twenty-sLxth Street, San Diego (Arnold, 1903, as A. limahda); "Saugus" formation near Ventura (WaterfaU, 1929, as A. peruviana); ujiper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: San Pedro, California, to Peru and the Galapagos Islands (DaU, 1921). This is the common Recent Anomia of the Pacific coast. It is variable in shape and general appearance due to the influence of situs. Generally it is thin and partly trans- lucent with irregular sculpture, sometimes almost smooth. A. UmatuJa Dall is based upon a slightly heavier and smoother specimen, but it appears to be within the limits of specific variation of the Recent form. VoLTJME I ] Pliocene and Pleistocene Mollusca of California 241 Anomia subcostata Conrad Anomia subcostata Conrad, U. S. House of Representatives, Doc. No. 129, p. 15, July, 1855; U. S. Pacific R. R. Repts. Vol. 5, p. 325, pi. 5, fig. 34, 1856; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 785, 1898; Kew, Univ. Calif. Publ. Geol., Vol. 8, p. 46, 1914; G. D. Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 460, pi. 23, figs. 3-5, 1926. Type specimen: In the U. S. National Museum. Type locality: Coyote Mountain, Imperial County; Pliocene. Pliocene: Carrizo (= Imperial) formation, lower division, several localities, and in the upper division at Carrizo Valley and Yuha Buttes, western Imperial County, California (Kew). This species, described by Conrad from the "Miocene" on Carrizo Creek, Colorado Desert, has strong radial sculpture. Its relationship to other Pacific coast species has not been studied. Genus PODODESMUS Philippi, 1837 Pododesmus Philippi, Wiegmann's Arch. f. Naturg. for 1837, p. 385, pi. 9, fig. 1, (1837 ?); Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 770, 779, 1898. Type (by monotypy), P. decipiens Philippi = Placunanomia rudis Broderip, Cuba, Recent. Shell variable, right valve rather flat, suborbicular, somewhat pearly; byssal plug passmg through foramen in right valve; a single conspicuous byssal scar present; hinge without teeth; valves sculptured with radial grooves. This genus lacks the cardinal crura of Placunanomia Broderip. The open byssal foramen of Pododesmus is a further distinguishing character. Anomia Linnaeus with the two byssal scars and thinner shell is quite distinct. Section Monia Gray, 1849 Monia Gray, Proc. Zool. Soc. London, for 1849, p. 121, 1850; Bucquoy, Dautzenberg and Dollfus, Moll. Marins du Roussillon, Vol. 2, fasc. 2, p. 41, August, 1888; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 771, 774, 1898. Type (by subsequent designation, Bucquoy, Dautzenberg and Dollfus, 1888), Anomia zealandica Gray, in Dieffenbach's New Zealand, p. 261, 1843; figured by Reeve, Conch. Icon., Vol. 11, Placunanomia, sp. 4, pi. 1, fig. 4, 1859, habitat New Zealand. Shell ovate, not plicated; radiately ribbed; perforation of lower valve large, only slightly em- bracing the large thin plug. (Gray, 1849.) Monia Gray is much like Pododesmus, s. s., but has a larger byssal opening. Pododesmus macroschisma (Deshayes) Plate 12, Figures 3, 4a, 4b Anomia macroschisma Deshayes, Rev. Zool. Soc. Couverienne, p. 359, 1839; Guerin's Mag. Zool., pi. 34, 1841; Mid- dendorff, Beitr. Mai. Rossica, Vol. 3, p. 6, 1849; Philippi, Abbild. Beschreib., Vol. 3, Anomia, p. 132, pi. 1, fig. 4, 1850. Placunanomia macroschisma Gray, Proc. Zool. Soc. London, for 1849, p. 121, 1849; Cat. Anom. Brit. Mus., p. 11, 1850; Reeve, Conch. Icon., Vol. 11, Placunanomia, sp. 7, pi. 2, fig. 7, 1859; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 646, 1864; Tryon, Struct. Syst. Conch., Vol. 3, p. 294, pi. 131, fig. 76, 1884; Cooper, 7th Ann. Rept. Cahf. St. Mineralogist, p. 260, 1888; Keep, West Coast SheUs, p. 163, fig. 137, 1888, 1892. Placunanomia cepio Gray, Proc. Zool. Soc. London, for 1849, p. 121, 1849; Cat. Anom. Brit. Mus., p. 11, 1850; Reeve, Conch. Icon., Vol. 11, Placunanomia, sp. 12, pi. 3, figs. 12a-6, 1859. Placunanomia alopc Gray, Proc. Zool. Soc. London, for 1849, p. 122, 1849; Reeve, Conch. Icon., Vol. 11, Placunanomia, sp. 11, pi. 3, figs, lla-b, 1859. 242 San Diego Society of Natural History [Memoirs Placunano7nia iyiacroschis7na Deshayes, Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 297, 1874. Placunanomia (Monia) macroschistna Deshayes, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 194, 1892. Pododesmus {Monia) macroschisma Deshayes, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 780, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 116, 1893; DaU, Bull. 112 U. S. Nat. Mus., p. 21, 1921; I. S. Oldroyd, Univ. Washington Publ. Puget Sound Biol. Sta., Vol. 4, p. 23, pi. 35, figs, la-b, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Monia maa-oschisma Deshayes, Dall, Amer. Jour. Sci., Ser. 4, Vol. 23 (whole No. 173), p. 457, 1907; Eldridge and Arnold, U. S. Geol. Surv., Bull. 309, p. 25, 1907; Arnold and R. Anderson, U. S. Geol. Surv., Bull. 322, p. 59, 1907; Berry, Nautilus, Vol. 22, p. 38, 1908; Arnold, U. S. Geol. Surv., Bull. 396, pp. 24, 25, 27, 75, 134, pi. 14, fig. 1, Jan. 15, 1910; Arnold and R. Anderson, Bull. 398, pi. 36, fig. 1, 1910; Dall in Moffit, BuU. 533, p. 45, 1913; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 219, 1917; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 26, pi. 3, figs. 1, 2, 1920. Pododesmus macroschisimis Deshayes, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pt. 5, p. 148, 1924. Pododesmus macroschisma Deshayes, Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 563, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 65, pi. 26, figs, la-b, 1924; E. K. Jordan, Proc. CaUf. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In British Museum ?. Type locality: Kamchatka, ^de Oldroyd, 1924. Pliocene: Lower and upper Etchegoin of Coalinga district (Arnold; Nomland); Fernando Pliocene of Santa Maria district, Santa Barbara County (Arnold and R. Anderson); middle Fernando of Elsmere Canyon, Los Angeles County (Eldridge and Arnold, 1907); Pico formation near Ventura (Water- faU); San Diego well, Balboa Park, San Diego (DaU, 1874); S. D. S. N. H., loc. 218, uppermost Pico, east of South Mountain, Ventura County; Otter Creek and Center, also second beach east of Nome, Alaska, supposedly Pliocene (Dall, in Moffit, 1913); Santa Barbara formation, upper Pliocene, at Bath-house Beach, Santa Barbara (Berry). Pleistocene: Lower Quaternary of Magdalena Bay, Lower California, Mexico (Jordan, 1924); Tomales Bay, Marin County (Dickerson); rare in the upper San Pedro series of San Pedro, Crawfish George's, and Deadman Island (Arnold, 1903); S. D. S. N. H. loc. 233, ridge north of Arroyo Santa Rosa, Ventura County (U. S. G. collector); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan, 1926); ?Pleistocene of Alaska (see below). Recent: Southern Bering Sea from the Pribilof Islands to Japan and the Okhotsk Sea on the west, and on the east south to and including the whole coast of Lower California, Mexico (Dall, 1921). This is the common Pododesmus of the Pacific coast. It is generally larger, heavier shelled, and has coarser radial sculpture than Anomia peruviana. It also has but one byssal scar. The occurrences in Alaska were attributed by Dall in the papers above cited to the Pliocene, but may be in part Pleistocene. It occurs at least as low as the Jacalitos formation, lower Pliocene, and is probably descended from Pododesjiius neiocomhei Clark and Arnold, 1 from the upper Oligocene or lower Miocene of Vancouver Island. This latter species appears to be smaller and more coarsely and evenly sculptured, the radial ribs being separated by wider interspaces. Genus PLACUNANOMIA Broderip, 1832 Placunano7nia Broderip, Proc. Zool. Soc. London, pp. 28, 29, 1832; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 770, 771, 1898. "Placunomia" Swainson, Treat. Malac, p. 390, 1840, "Abridged from Placunanomia Sow."; Woodward, Man. Mol- lusca, pt. 2, p. 255, 1854. Type (by monotypy), Placunanomia cumingii Broderip, Central American and west Mexican coasts, Recent. Shell with interlocking rugosities on the cardinal margias of the valves; right valve with two prominent elevated ridges converging acutely at the cardinal margin and fitting into a corresponding iaipartite socket m the left valve; right valve with one prominent subcentral adductor scar and about ' Univ. Calif. Publ. Geol., Vol. 14. p. 141, pi. 21, figs. 3-6, 1923. Volume I J PlIOCENE AND PLEISTOCENE ^NloLLUSCA OF CALIFORNIA 243 half way between it and the lower ends of the crura the closed (in adult) byssal foramen is equally prominent; left valve with the conspicuous adductor and byssal scars adjacent; inner surface of l)oth valves somewhat pearly ; valves with few strong, subangular plications. This genus is very different from Anomia and Pododesmus as noted on preceding pages. Pododesmus macrochisma Deshayes has been referred to Placunanomia probably because of Stoliczka's citing this species as type. Placunanomia cumingii Broderip Placunanomia cumingii Broderip, Proc. Zool. Soc. London, Pt. 2, p. 29, 1832; Reeve, Conch. Icon., Vol. 11, Placu- nanomia, pi. 1, figs. 3a-b, 1859; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. i, Vol. 15, pp. 215, 216, pi. 23, fig. 4, 1926. Type locality: Gulf of Dulce, Costa Rica, Recent. Pliocene: In the cliffs about one mile south of the village, Maria Madra Island, Mexico. Recent: Gulf of California, Mexico, to Gulf of Dulce, Costa Rica. This species, the type of the genus, is characterized by the few strong, subangular plications and the lack of radial striations. Placunanomia califomica Aanold Placunanomia califomica Arnold, U. S. Geol. Surv., BuU. 396, p. 75, pi. 2-1, figs. 2, 2a, 3, Jan. 15, 1910; Arnold and R. Anderson, BuU. 398, pi. 46, figs. 2, 2a, 3, 1910. Type specimen: U. S. National Museum, No. 165,546. Type locality: South of Kettleman Hills, Sec. 10, T. 25 S., R. 19 E., Mt. Diablo B. and M., Coalinga district, Pliocene. Pliocene: Upper portion of the Etchegoin formation at the type locality, Coalinga district, rare (Arnold). This rare species differs from P. cumingii in the presence of radial riblets and the very low, almost obsolete plications. P. hannibali Jordan and Hertlein is very closely related, but has finer radial sculpture and the byssal scar is not sub-triangular as in Arnold's species. Placunanomia hannibali Jordan and Hertlein Placunanomia hannibali E. K. Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Xo\. 15, pp. 443, 444, pi. 28, figs. 2-4, 1926. Type specimen: California Academy of Sciences, No. 2,110. Type locality: Southeast of Turtle Bay, Lower California, Mexico; upper Pliocene. Pliocene: .\t the type locality (Jordan and Hertlein). This species is closely related to P. californica Arnold, but the radial sculpture is much finer. It appears to attain a larger size and the byssal scar does not have the sub- triangular shape of the type of californica. Numerous specimens were obtained at the type locality. When more specimens of this species and californica become available for study, it may be necessary to reduce hannibali to varietal or synonymic status. 244 San Diego Society of Natural History [Memoirs Superfamily Mytilacea Family MYTILIDAE Shell equivalve, ovate or elongate; umbones anterior; hinge edentulous or with small or obscure teeth; ligament internal or submarginal; byssus generally present; inner shell layer sometimes na- creous or subnacreous; pallial line entire. Genus MYTILUS Linnaeus, 1758 Mytilus Lmnaeus, Syst. Nat., Ed. 10, p. 704, 1758; Children, Quart. Jour. Sci., Lit., Arts, Vol. 15, p. 33 (pi. 1, fig. 79), April, 1823; Gray, Proc. Zool. Soc. London for 1847, p. 198, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 785-787, 1898; Jukes-Browiie, Proc. Malac. Soc. London, Vol. 6, p. 217, 1905. Not Mytilus Linnfeus, as restricted by Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 107, 1817. Type (by subsequent designation, Gray, 1847, see below), Mytilus edulis Linnaeus, cosmopolitan. Shell elongate, rather thin; beaks terminal, pointed; generally wider and rounded beliind, and with a slight byssal gape; sculpture consi.sting of concentric undulations, and sometimes radial ribs, which may be wide and indefinite or fine and miifonn ; epidermis present, often dark ; interior of shell with a thin nacreous layer; hinge edentulous or with a few small teeth. Geologic range: Mesozoic to Recent. Distribution : Cosmopolitan. We retain the Linnaean name Mytilus for the shells so well known under this designa- tion in spite of Schumacher's citation of the "figure of the hinge of" Anodonta anatina [Mytilus anatinus Linnseus) as the type of the genus. To follow Schumacher would make Mytilus the valid name for Anodonta Bruguiere; but as it undoubtedly will be but a matter of time before the International Commission suspends the rules in favor of retaining Mytilus in its generally accepted sense, it would merely cause confusion to transfer Mytilus to the fresh-water Anodontas in the interim. There might be some doubt in re- gard to the manner in which Schumacher cites the type, but a special ruling should settle the matter permanently. Subgenus MYTILUS, s. s. Umbonal end of shell not greatlj' thickened. Section Mytilus, s. s. Sculpture when present consisting of incremental undulations and coarse, often indefinite or subdued radial ribs, sculpture sometimes lacking ; fine bifurcating riblets absent. Mytilus (Mytilus) edulis Linnaeus Mytilus edulis Linnseus, Syst. Nat., Ed. 10, p. 705, 1758; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 252, 1888; Bucquoy, Dautzenberg and DoUfus, Moll. Mar. Roussillon, Vol. 2, fasc. 4, pp. 136-143, pi. 26, figs. 1-4, 1890; Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 118, 119, 1903; Thompson, Rept. Brit. Columbia Com- missioner of Fisheries for 1912, p. 1-40, pis. 7, 11, 1913; DaU, in Moffit, U. S. Geol. Surv., Bull. 533, pp. 46, 47, 1913; Dall, Canadian Arctic Exped., Vol. 8, Pt. A, p. 28A, 1919; Weymouth, Calif. Fish and Game Comm., Bull. No. 4, p. 27, pi. 3, fig. 4, 1920; U. S. Nat. Mus., Bull. 112, p. 21, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 66, pi. 27, fig. 4, 1924. Mylilus pedroanus Conrad, U. S. House of Representatives, Document No. 129, p. 15, July, 1855 (reprinted by Dall, U. S. Geol. Surv., Prof. Paper 59, p. 167, 1909); U. S. Pacific R. R. Repts., Vol. 5, p. 325, pi. 5, fig. 40, 1856. Mytilus ficus DaU, U. S. Geol. Surv., Prof. Paper 59, p. 113, pi. 9, figs. 1, 4, 1909; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 245 Miocene: ?. Pliocene: Submarine beach west of Snake River; of Center Creek; of submarine beach west of Nome, and second beach one and a half miles east of Nome, all Alaska (Dall, 1913); Empire formation of Coos Bay, Oregon (as M.ficus Dall); Pliocene of the Red Crag, England, etc. Pleistocene: South Side of Bernard Harbor, northern Canada; mouth of Inman River; Dolphin and Union Strait, Northwest Territories (Dall, 1919); Benecia, Solano Countj* (Cooper); lower San Pedro series of Deadman Island, rare; upper San Pedro series of Deadman Island, Crawfish George's, and San Pedro (Arnold) ; Atlantic coast, etc. Recent: Arctic Ocean to San Diego; cosmopolitan in temperate waters. This species is too well known to need description. A large series of specimens from many different localities exhibits variations which, in shape, include a large number of supposed species described from the Pacific coast Tertiary. The references and data on occurrence given above are much abbreviated. The earliest occurrence of M. edulis on the Pacific coast may be in the lower Miocene, where it is represented by Mytilus sam- mamishensis and M. snohomishensis Weaver (Wash. Geol. Surv., Bull. 15, pp. 58, 59, 1912), two Blakeley formation forms which are probably one and the same species and either conspecific with edulis or its ancestor. M. stillaguamishensis Weaver was unfigured and the description suggests no valid characters by which to distinguish it from the other two forms from apparently the same horizon. Mytilus (Mjrtilus) califomianus Conrad Plate 12, Figure 6 Mytilus califomianus Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 242, pi. 18, fig. 15, 1837; Reeve, Conch. Icon., Vol. 10, Mytilus, pi. 1, figs. 2a-6, 1858; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 26, pi. 4, figs. 1, 2, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 21, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 66, pi. 27, fig. 2, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 3, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Shell ovate elongated, inflated ; anterior margin straight ; posterior side emarginate ; ribs not very numerous, slightly prominent, broad, rounded; lines of growth very prominent. Length, 2]/^ inches. (Conrad.) Type locality: San Diego, California. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, "part of one valve" (T. S. Oldroyd); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Unalaska, Aleutian Islands, eastward and southward to Socorro Island, Mexico (Dall). This common large Mytilus of the Recent California fauna is characterized by its few, obscure, rather broad radial riblets. Section Hormomya Morch, 1853 Hnrmomya Morch, Cat. Yoldi, fasc. 2, p. 53, 1853. '^Brachydontes Swains.," Gray, Proc. Zool. Soc. London for 1847, p. 199, 1847, type Mytilus exuslus. Type (here designated), M. exustus Linnaeus. Shell sculptured with numerous, fine, closely, spaced, bifurcating riblets. The type of this section has a distinctive sculpture of numerous, small, bifurcating ribs which are quite different from the broad, unequally developed ribs on such species as M. californicus. The section is poorly represented on the Pacific coast, M. adamsianus Dunker (Proc. Zool. Soc, 1856, p. 360) being the only native California Recent species. Gray associated this group with Brachidontes, although the latter has a slightly pro- duced, Volselloid, anterior margin. To judge by a few Recent specimens from Florida, 246 San Diego Society of Natural History [Memoirs the two groups come very close to intergrading, and it is not unlikely that the separation is artificial. Perhaps Brachidontes should be recognized as a genus intermediate between Mytilus and VoIseUa, with Hormomya as a section. Subgenus MYTILOCONCHA Conrad, 1862 MytiJoconcha Conrad, Proo. Acad. Nat. Sci. Phila., Vol. 14, p. 290, 1862; Dall, Trans. Wagner. Inst. Sci., Vol. 3, p. 7S7. 1S9S. Type (by subsequent designation, Dall, 1898), M. incurvus Conrad, Fossils of the Medial Tertiary of the United States, No. 1, cover page 3, 1838, No. 2, pp. 52, 53, pi. 28, fig. 1, 1840 (text and figures republished by Wagner Free Inst. Sci., 1893), Miocene of Maryland. Shell curved, thick; Iseaks pointed, somewhat divergent distally, and greatly thickened inter- nally, with a ridge and a long furrow or groove for the cartilage. Conrad originally described the type species under Myoconcha Sowerby,' a Jurassic genus having considerable similarity. Later he proposed Mytiloconcha for the Maryland Miocene shell, which is adopted for M. coaliyigerisis Arnold and such other Pacific coast species as may prove upon examination to have the peculiar heavy terminal hinge of the type. Conrad's later spelling Mytiliconcha is inadmissible. Mytilus (Mytiloconcha) coalingensis Arnold Mytilus (Mylilocoricha) coalingensis Arnold, U. S. Geol. Surv., Bull. 396, p. 73, pi. 19, fig. 5, pi. 22, fig. 6, Jan. 15, 1910; Bull. 398, pi. 41, fig. 5, pi. 44, fig. 6, 1910; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 419, 1915. Mytilus coalingensis Arnold, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 2.52, 1916; Nomland, Vol. 10, p. 219, 1917. Type specimen: U. S. National Museum, Cat. No. 165,551. Type locality: Coalinga region, California, Etchegoin, middle Pliocene. ? Miocene: ? Upper San Pablo, upper Miocene, questionably as a new variety (Clark). Pliocene: Etchegoin formation of Coalinga region (Arnold); common in the Pecten coalingensis zone, Coalinga region, also questionably in the Turritella nova zone (Nomland); Etchegoin, and Merced of the Sargent oil field, near Sargent, Santa Clara Coimty (Martin). This species has the greatly thickened terminal hinge characteristic of typical Mytiloconcha. It differs from M. {Mytiloconcha) incurvus Conrad in being larger, broader, and in having a prominent muscle pit just anterior to the beaks. Mytilus trampasensis Clark^ of the upper Miocene has been considered a Mytilo- concha, but we are not aware that the hinge has been examined. This species is probably conspecific with M. perrini Clark from the same formation. M. mathcu'sonii Gabb is a typical Mytilus and is more closely related to M. edulis than to M. incurvus. The subgeneric position of the following species is unknown to us. Mjrtilus kewi Nomland Mytilus kemi Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 206, pi. 9, fig. 1, 1916; Vol. 10, pp. 299, 300, 304, pi. 14, fig. 1, 1917; not M. kewi Wiedey, Journ. Paleo., Vol. 3, p. 281, pi. 31, fig. 2, 1929, = M. loeli Grant, Journ. Paleo., Vol. 4, p. 419, 1930. Type specimen: In the collection of the University of California. ^ Min. Conch. Gt. Britain, Vol. 5, p. 103, pi. 467, 1825, Myoconcha crassa Sowerby, monotype, from the Ironshot Oolite near Bristol. ' Univ. Calif. Publ. Geol., Vol. 8, pp. 457, 458, pi. 42, figs. 2, 3, 1915. Volume 1 ] PLIOCENE AND PLEISTOCENE MOLLTJSCA OF CALIFORNIA 247 T]jj>e locality: On Jacalitos and Waltham Creeks, Fresno County, Etchegoin, lower Pliocene. Miocene: Santa Margarita formation, upper Miocene, north of Coalinga, also from the Santa Margarita for- mation on the Nacimicnto River, several miles west of San Miguel, San Luis Obispo County (Nomland, 1917). Pliocene: Lower and middle Etchegoin, lower and middle Pliocene, Coalinga region (Nomland, 1916). M. hewi Nomland was stated to be smaller than M. coalingensis Arnold with less acute and thickened beak. It also has a depression extending from beak to basal margin. Mytilus middendorffi Grewingk Mylihis middendorffi Grewingk, Verhandlungen der Russisch-Kaiserliehen Mineralogischen Gesellschaft zu St. Peters- burg, Jahrgang 1848 and 1849, No. 6, pp. 167, 171, 360, pi. 7, figs. 3o-f, 1850; Dall, 17th Ann. Kept. U. S. Geol. Surv., Pt. 1, p. 844, 1896; Dall, Harriman Alaska Series, Vol. 4, p. 113, 1904, reissued by Smithsonian Inst., 1910. Miocene: Unga Island and Kadiak Island, near Cape Tonki, Igatskoi Bay, Alaska (Grewingk; Dall). This species differs from all other Pacific coast Neocene and Quaternary species in the broad plications on the distal portions of the valves. Dall has given its occurrence in Alaska as Miocene. ^ In the geology volume of the Harriman Alaska report Dall states that this species is represented in the Pliocene of Oregon by Mytilus condoni Dall, but we have found no description of this latter species. Perhaps it is the species which Dall later called Mytilus ficus, although that form as figured is not similar to Grewingk's figure of middendorffi. Unless condoni has been actually described, it must be considered a nomen nudum. Genus SEPTIFER Recluz, 1848 Seplifer Recluz, Rev. Zool., p. 27.5, 184S; Stoliczka, Pal. Indica, Cret. Pelecypoda So. India, p. 366, 1871; Harris, Cat. Tert. Moll. Brit. Mus., Pt. 1, p. 328, 1897. Type (fide Stoliczka, 1871), Mytilus bilocularis Linnaeus. Shell like that of Mytilus, luit with an umbonal deck. Septifer bifurcatus (Conrad) Mytilus bifurcatus Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 241, pi. 18, fig. 14, 1837; Reeve, Conch. Icon., Vol. 10, Mytilus, pi. 9, fig. 41, 1851; Williamson, Nautilus, Vol. 12, pp. 67, 68, 1898. Septifer bifurcatus Reeve, Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 101, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 264, 1888; Keep, West Coast Shells, p. 171, fig. 144, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 191, 1892; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 789, 1898; Keep, West American Shells, p. 33, fig. 15, 1904; E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2, 1919. Septifer bifurcatus Conrad, Pilsbry and Raymond, Nautilus, Vol. 12, pp. 69, 70, 1898; .Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 119, 1903. Septifer bifurcatus (Conrad) Reeve, Dall, Bull. 112, V. S. Nat. Mus., p. 21, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 67, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; T. S. Oldroyd, Proc. n. S. Nat. Mus., Vol. 65, Art. 22, p. 4, 1925. Shell narrowed, slightly arcuate; anterior margin much flattened; ribs narrow, prominent, bi- fureatmg toward the base; color dark purple. Height II/2 inches. (Conrad.) 1 Eichwald, p. 128, 1871, attributes this species to the Cretaceous and identifies it with Modiota dufrenoyi d'Orbigny from the Senonian, U. Cretaceous of Europe. See the note on Mya arenaria variety pro/undior, p. 414. 248 San Diego Society of Natural History ( Memoirs Pleistocene: San Pedro series of Deadman Island, rare (Arnold); lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd) ; Pleistocene at San Diego (Mrs. K. Stephens, MS.) ; Pleistocene of the Chiton bed, Point Firmin, Los Angeles County (E. P. and E. M. Chace); lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Crescent City, California, to Gulf of California, Mexico (Dall). Septif er margaritanus Nomland Septifer margaritana Nomland, Tniv. Calif. Publ. Geol., Vol. 10, pp. 308, 309, pi. 19, fig. 5, 1917. Type specimen: University of California collection, No. 11,310. Type locality: Santa Margarita beds about ten miles northeast of Coalinga. Miocene: Type locality. This species is larger and has more numerous radial ribs than S. bifurcatus, and the umbonal ridge is more marked. Neither the description nor the figure throw light on the presence or absence of an umbonal deck, and we have not seen specimens. Genus VOLSELLA Scopoli, 1777 (Modiolus Lamarck, 1799) Volsella Scopoli, Introd. Hist. Nat., p. 397, 1777; Gray, Proc. Zool. Soc. London, for 1847, p. 198, 1847; Meek, V. S. Geol. Surv. Territories, Vol. 9, pp. 69-71, 1876; Bucquoy, Dautzenberg and DoUfus, Moll. Mar. Roussillon, Vol. 2, fasc. 4, p. 150, 1890; Jukes-Browne, Jour. Conchology, Vol. 11, p. 101, 1904; Dautzenberg and Fischer, Hirondelle et Princesse Alice Rept., p. 366, 1912. Modiolus Lamarck, M6m. Soc. Hist. Nat. Paris, p. 87, 1799; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 790, 791, 1898. Modiola Lamarck, Syst. Anim. s. Vert., p. 113, 1801; Bucquoy, Dautzenberg and Dollfus, Moll. Marins Roussillon, Vol. 2, fasc. 4, p. 1.50, 1890; Jukes-BrowTie, Proc. Malac. Soc. London, Vol. 6, p. 221, 1905. Type (by subsequent designation, Gray, 1847), Mytilus modiolus Linnaeus, European seas, Recent. Shell obliquely oblong, expanded posteriorly and inflated along an oblique medial line from the umbonal end to the posterior ventral margin ; anterior end produced beyond imibones ; hinge edentu- lous in adult. In Scopoli's rare work, "Introductio ad Historian! Naturalem," a copy of which is at hand, the name Volsella is proposed for a genus of supposedly denticulate Mytilidce, the first species of which is Mytilus modiolus Linnseus, described as having one tooth. The second species, "Gula soricis" of Lister, is unknown to us, and the third and only remain- ing species is "Mytilus I'aber" of Adanson. The last species is figured by its author in his work on Senegal in such a manner that the hinge characters are indeterminable, but Scopoli attributes to it "dentibus pluribus." It is therefore evident from Scopoli's text^ that his inclusion of Mytilus 7yiodiolus Linnaeus in this group was due to some misconcep- tion of the hinge characters of his first species, but as the generic name in all respects fulfills nomenclatorial requirements and antedates Lamarck's Modiolus, it must be used in place of the latter. Volsella Scopoli is not a homonym of Vulsella Bolten. Volsella has been divided into several minor gi'oups, some of which appear natural, while others are clearly artificial. The species listed below belong to the typical sub- genus, unless otherwise noted. » Volsella, Pleria, Solen, Mya, and other genera are placed under a heading "Cardine dendato." Scopoli might have been referring to the young of Volsella, which 8ometime3 show traces of taxodont teeth. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 249 Volsella modiolus (Linnaeus) Mylilus modiolus Linnaeus, Syst. Nat., Ed. 10, p. 706, 1758; Chemnitz, Neues Syst. Conch. Cab., Vol. 8, p. 178, pi. 85, fig. 757, 1785. Modiola modiolus Linnaus, Reeve, Conch. Icon., Vol. 10, Modiola, pi. 1, fig. 2, 1858; Clessin, in Martini und Chemnitz, Conch. Cab., Ed. 2, Mytilids!, p. 92, pi. 5, fig. 3, 1889; Lamy, Jour. Conchy]., Vol. 57, p. 229, 1909. Modiolus modiolus Lamarck, E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2 (p. 42), 1919. Modiolus modiolus Linnaeus, Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 596, 1913; Dall, U. S. Nat. Mus., Bull. 112, p. 21, 1921; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 1, p. 68, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pt. 5, p. 153, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 4, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type s-pecivien : In the collection of the Linnsean Society of London? Pliocene: Elk River formation, upper Pliocene, north of mouth of Elk River, Port Orford, Oregon (Arnold and Hannibal); lower San Pedro fauna of Nob Hill, San Pedro (T. S. Oldroyd). Pleistocene: Plei.stocent of the Chiton bed. Point Firmin, near San Pedro (E. P. and E. M. Chace); upper Quaternary at San Quintin Bay, Lower California, Mexico (E. K. Jordan). Recent: On the Pacific coast from the Arctic Ocean to San Ignacio Lagoon, Lower California, Mexico (E. K. Jordan); circumboreal. V. modiolus (Linnaeus) is characterized by its rather blunt umbonal end, with the shell but little produced beyond the end of the beaks. The valves are rather broad (deep), being alate dorsally. The sculpture consists entirely of incremental lines. Living speci- mens have a dark brown or chestnut colored glistening epidermis. V. capax (Conrad), which is closely related, is similar in appearance, but has a much heavier shell, is often larger, and is more inflated along the line running obliquely from the umbones to the posterior part of the valves. In consequence of this greater inflation of the valves of capax, the dorsal area between the umbones is more depressed. V. capax generally has a rougher, partly hirsute epidermis. V. modiolus has an imposing list of synonyms which are omitted here to conserve space. Volsella capax (Conrad) Modiola capax Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 242, 1837; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 121, 1857; Reeve, Conch. Icon., Vol. 10, Modiola, pi. 3, fig. 11, 1859; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 146, 1894; MabiUe, Bull. Soc. Philomathique de Paris, Ser. 8, Vol. 7, p. 73, 1895. Modiolus capax Conrad, Clark, Univ. Calif. Publ. Geol., Vol. 8, table opp. p. 408, p. 418, 1914; Dall. U. S. Nat. Mus., Bull. 112, p. 22, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 69, 1924; T. S. Oldroyd, Proc. V. S. Nat. Mus., Vol. 65, Art. 22, p. 4, 1925: Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type specimen: At the Academy of Natural Sciences, Philadelphia?. Type locality: San Diego, California; Recent. Miocene: Santa Margarita formation and upper San Pablo of middle California (Clark). Pliocene: Etchegoin formation of middle California (Clark); Pico formation, upper Pliocene, near Ventura (Waterfall). Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, "one valve" (T. S. Oldroyd). Recent: Santa Barbara, California, to Payta, Peru (Dall, 1921). This species is similar to V. modiolus, but is heavier shelled, more inflated, and has a more depressed region between the umbones. Volsella recta (Conrad) Modiola recta Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 243, pi. 19, fig. 1, 1837; Reeve, Conch. Icon., Vol. 10. Modiola, pi. 7, fig. 38, 1857; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 643, 1864; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 101, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 251, 1888; Keep, West Coast Shells, p. 171, fig. 145, 1888, 1892. 250 San Diego Society of Natural History [ Memoirs Modiolus rectus Conrad, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 793, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 120, 121, 1903; Keep, West American Shells, p. 34, fig. 16, 1904; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 526, 1907; Arnold, Bull. 396, U. S. Geol. Surv., p. 146, pi. 20, fig. 4, Jan. 15, 1910; Arnold and R. Ander.son, Bull. 398, pi. 42, fig. 4, 1910; Arnold and Hannibal, Proc. ,\mer. Philos. Soc, Vol. 52, no. 212, pp. 588, 590, 596, 1913; Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 203, 1916; Martin, Vol. 9, p. 252, 1916; Nomland, Vol. 10, p. 211, 1917; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 27, pi. 4, fig. 3, 1920; Dall, Bull. 112, U. S. Nat. Mus., p. 22, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 68, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Modiolus directus Dall, U. S. Geol. Surv., Prof. Paper 59, p. 113, pi. 12, figs. 11, 12, 1909; Weaver, Washington Geol. Surv., Bull. 15, p. 18, 1912; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 588, 590 (including directus Dall), 596, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 418, 1915; Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 28, 1916; Van Winkle, Univ. Wash. Publ. Geol., Vol. 1, no. 2, p. 75, 1918. ? Oligocene: Blakeley formation, Oligocene or lower Miocene of the Chahalis Vallev, Washington (Van Winkle). Miocene: Miocene of the basal sandstone, foot of 19th Street, Astoria, Oregfin, and of the massive sandstone in the sea cliffs at Pillar Point near Clallam Bay, Washington (Arnold and Hannibal) ; Empire for- mation of the Coos Bay, Cape Blanco district, southwestern Oregon (Arnold and Hannibal; Dall, 19C9; Howe; etc.); Montesano formation (Weaver); upper San Pablo formation of middle California (Clark, 1908); Miocene of El Toro ranch, Monterey County; Foxin's, Santa Barbara County (Cooper); Santa Margarita formation of middle California (Nomland, 1917). Pliocene: Lower Pliocene on Jacalitos and Waltham Creeks, Coalinga district (Nomland); common in the Chione elst>ierensis, Turritella nova, and Pecteii coaUngensis zones, and rare in the Mi/a japonica zone of the Etchegoin formation in the Coalinga district (Nomland, 1917) ; lower Pliocene of ELsmere Canyon, Los .A.ngeles County (Arnold, 1907); Santa Rosa; Twelve Mile House, San Mateo County; Soquel, Santa Cruz County; San Fernando, Los Angeles County; San Diego well, Balboa Park, San Diego (Cooper, 1888); Pacific Beach, San Diego County (Arnold); Purisima of Santa Clara County; lower Merced formation; Merced of the Sargent oil field, near Sargent, Santa Clara County; Merced of Bolinas Bay and of Ano Nuevo Bay (Martin); Pico, upper Pliocene part, near Ventura (Waterfall); Santa Barbara formation, upper Pliocene at Bathhouse Beach, Santa Barbara (Arnold). Pleistocene: Rare in lower San Pedro series of Deadman Island (Arnold, 1903); Post-Pliocene of Santa Bar- bara (Cooper); Barlow Canyon, Ventura County (Arnold, 1903); Pleistocene at Pacific Beach and at foot of 26th Street, San Diego (Arnold, 1903; Mrs. Kate Stephens MS.); upper Pleistocene at San Quintin Bay, Lower California, Mexico (E. K. Jordan). Recent: Bolinas Bay, California, to Magdalena Bay, Lower California, Mexico (Dall, 1921); [variety /abeZ- lata, Vancouver Island to San Diego.] This species differs from V. modiolus (Linnaeus) in the greater extension beyond the beaks of the antepor alation; also the anterior half of the dorsal margin of the valves is straighter, the dorsal alation occurring posterior to the middle. V. recta attains a larger size and is often more elongate than 1'. modiolus. Volsella recta Conrad occurs at least as early as the lower Miocene. The Modiolus directus of Dall appears to us to be conspecific with Conrad's species. The amount of alation beyond the beaks is variable; and this part of the shell margin, being rather thin and vulnerable, is subject to shortening by erosion. Volsella recta (Conrad) variety flabellata (Gould) Plate 12, Figure 7 Mytihis (Modiola) flabeUntus Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 343, Dec, 1850; U. S. Expl. Exped., Vol. 12, p. 4.53, 18.52, MoUusca Atlas, pi. 40, figs. 561, 561rt, 1856. Modiolus flabellaius Gould, Dall, Bull. 112 U. S. Nat. Mus., p. 22, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 68, pi. 6, fig. 2, 1924. Type locality: Puget Sound; Recent. Pleistocene: Las Posas zone, lower Pleistocene, S. D. S. N. H. loc. 241a, float just east of Harmon Canyon, Ventura County (coll. by U. S. G.). Recent: Vancouver Island to San Diego, California (Dall, 1921). Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 251 This form is close to recta, but is larger, less ventricose, particularly at the umbones, and the anterior alation projects farther forward. It frequently dwells buried in mud with just a portion of the shell projecting. It is probable that some of the fossil records of V. recta refer to this variety, variation, or gerontic form. Volsella fomicata (Carpenter) Modiolafornicata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1S6.3, p. 643, 1S64; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 179, 1S6.5; Keep, West Coast Shells, p. 173, 18SS, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 1.5, p. 191, 1892. Modiolus fornicatus Carpenter, Arnold, Mem. Calif. .\cad. Sei., Vol. 3, p. 120, 1903; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 219, 1917; DaU, U. S. Nat. Mns., Bull. 112, p. 22, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Howe, Univ. Calif. Publ, Geol., Vol. 14, p. 92, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 69, 1924. Type specimen: In the collection of Mrs. Boyce, Utica, N. Y., fide Oldroyd. Type locality: Santa Barbara, California; Recent. Pliocene: Rare in the Pecten coalingensis zone, upper Pliocene part of the Etchegoin formation, Coalinga region (Nomland); Santa Barbara formation, upper Pliocene, at Bath-house Beach, Santa Barbara (Arnold). Phistoane: Rare in lower San Pedro series of Deadman Island. Los .4ngeles County; "Saugus" formation of Barlow Canyon, just cast of Ventura (.Arnold); lower Quaternary of Magdalena Bay, Lower Cali- fornia, Mexico (E. K. Jordan ) ; upper San Pedro series of Los Cerritos (.Arnold). Recent: Trinidad to San Pedro and Cortez bank off San Diego, California (Dall). In this species the beaks curve strongly forward, downward and backward so that a portion of their curve projects considerably beyond the anterior margins of the valves. In the Oldroyd Collection at Stanford University there is a Recent specimen from Mon- terey which is unusually large and swollen; it has the following measurements: extreme anterior-po.sterior length, 32 mm. ; dorsal-ventral height, 16J^ mm. ; thickness of both matched valves together 20 mm. Volsella trinominata is much larger, does not have such a pronounced curvature of the umbones, is less ventricose, and is broader posteriorly. Volsella for 7iicata (Carpenter) may not belong to the typical section of the genus. Volsella trinominata (Hanna) Modiolus inflatvs Dall, U. S. Geol. Surv., Prof. Paper .59, p. 114, pi. 12, figs. 8, 9, 1909; Weaver, Washington Geol. Surv'., Bull. 15, p. 18, 1912. Modiolus Irinominata G. Dallas Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 171, March 18, 1924, new name for Modiolus inflaliis Dall, not Modiolus inflatus (Tuomey and Holmes) Pleiocene Fossils of South Carolina, p. 33, pi. 14, fig. 3, 1855, as Myiilus; nor Modiola {Lithodomus ?) inflala Whitfield, U. S. Geol. Surv-., Monogr. 9, p. 197, pi. 26, figs. 1, 2, 1885. Type specimen: U. S. National Museum No. 153,946. Type locality: Coos Bay, Oregon; Miocene. Miocene: Coos Bay, Oregon (Dall); Blakeley formation, probably lower Miocene, western Washington (Weaver). This species is said to be less alate and angulate dorsally than capax, and more evenly convex anteriorly. Howe considered it a synonym oi fomicata (Carpenter), but Ball's figure of ")nflat2is" is so different from specimens of Carpenter's species that we do not beUeve the two species to be conspecific. The beaks of Volsella fomicata are strongly curved so that they project forward, downward, then backward, and a part of them por- jects considerably beyond the actual anterior margin of the valves. Posteriorly, fomicata is narrower than "iyiflaius" and the entire shell is much smaller. 252 San Diego Society of Natural History [ Memoirs Subgenus BRACHIDONTES Swainson, 1840 Brachidontes Swainson, Treat. Malac, p. 384, 1840. Not "Brochydontes Swains.," Gray, Proc. Zool. Soe. London, for 1847, p. 199, 1847, type Mytilus exuslus. Type (by monotypy), Modiola sulcata Lamarck, Indian Ocean; Recent; figured by Reeve, Conch. Icon., Vol. 10, Modiola, pi. 10, fig. 74, 1858. Like Volsella, s. s., but with numerous, well-defined radial riblets; shell generally of medium or small size. Gray altered the original spelling to Brachydontes, which is inadmissible. His desig- nation of Mytilus exustus as type is not valid, as that species was not in Swainson's original list. Volsella (Brachidontes) stalderi (Martin) Modiolvs stalderi Martin, Univ. Calif. Publ. Geol., Vol. S, pp. 182, 183, pi. 22, figs. 6a-b, August 6, 1914. Type specimen: In the University of California collections. Type locality: Near Ferndale, Humboldt County, CaUfornia; Pliocene. Pliocene: In the sea cliff at the mouth of a small gulch one-third of a mile north of the mouth of Guthrie Creek, about eight miles southwest of Ferndale, Humboldt County, the type locality (Martin). This species differs from the Recent Brachidontes demissus (Dillwyn), which has been introduced into San Francisco Bay from the Atlantic on seed oysters, in being less pointed anteriorly and less incurved ventrally. It unquestionably belongs to Brachidontes Swain- son. Genus BOTULA Morch, 1853 Botula Morch, Catalogus Conchyl. Yoldi, fasc. 2, p. 55, 1853; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 792, 1898. Type (by subsequent designation, Dall), Botula fusca (Gmelin).' Shell long, subcylindric or rhombic; beaks subterminal or suljcentral. Section Adula H. and A. Adams, 1857 Adida H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 517, Dec, 1857; Dall, Trans. Wagner last. Sci., Vol. 3, p. 799, 1898. Type (by monotypy), Botula {Adula) soleniformis (d'Orbigny). Shell rhombic, with subcentral beaks; surface of valves polished, not incrusted. Botula falcata (Gould) Lithodomvs falcalus Gould, Proc. Boston Soc. Nat. Hist., Vol. 4, p. 92, 1851. Adula falcata Gould, Keep, West Coast Shells, p. 170, fig. 143, 1888, 1892. Botula falcata Gould, Dall, U. S. Nat. Mus., BuU. 112, p. 22, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 71, pi. 21, figs. 8, 9, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 4, 1925. Type locality: Monterey, California; Recent. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, California (T. S. Oldroyd). Recent: Coos Bay, Oregon, to San Diego, California (Dall). * Morch included but two specifically named species in his original generic list, the second being fitsca (Gmelin) , under which Morch gives as a synonym "Modiola cinnantomea var. Lam." Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 253 This species is similar to B. californiensis Philippi, 1847, but is larger, more elongate, and the valves are sculptured with peculiar vertical striations. B. diegensis Dall' is still smaller and much broader. Mr. A. M. Strong points out that the latter species is probably a Volsella; it is not a rock borer. Genus LITHOPHAGA Bolten, 1798 Ldthophaga J. F. Bolten, Mus. Boltenianum, p. 1.56, 1798. Ldthodomus Cuvier, Le R6gne Animal, Vol. 2, p. 471, 1817. Type (by monotypy), L. mxjtuloides Bolten = Mytilus lithophagus Gmelin. Shell elongate, sub-cylindrical, inflated anteriorly and wedge shaped posteriorly. The wedge-shaped posterior end of the shell serves to differentiate this genus from Botula. Section Lithophaga, s. s. Beaks nearly terminal; surface polished, without calcareous incrustation. Section Diberus Dall, 1898 Dibenis Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 799, 1898. Type (by original designation), L. plumula Hanley. Shell with two or more radial sulci extending backward from the beaks; with a plume-like incrustation arranged in a distinct pattern on the areas between the sulci, and when projecting beyond the ends of the valves, opposed symmetrically. Myoforceps Fischer, 1886, is similar, but the incrustation projecting beyond the ends of the valves is twisted. Lithophaga plumula (Hanley) Lilhodomus plumula Hanley, Proc. Zool. Soc. London, for 1844, p. 17, 1844; Reeve, Conch. Icon., Vol. 10, Lilhodomus, pi. 4, fig. 23, 1857; Lamy, Jour. Conchyl., Vol. 57, p. 229, 1909. Lithophagus plumula Hanley, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 125, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, p. 644, 1864; Keep, West Coast Shells, p. 171, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 192, 1892. Lithophaga plumula Hanley, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 799, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 121, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 23, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 73, 1924. Type locality: Panama; Recent. Pleistocene: Upper San Pedro series at Los Cerritos (Signal Hill), Los Angeles County (Arnold). Recent: Monterey, California, to Patagonia; also Atlantic. The peculiar, coarsely and irregularly grooved incrustation serves to distinguish this species. It is the common rock borer of the southern California coast, being abundant in favorable localities. Genus MODIOLARIA Beck, 1838 Musculus Bolten, Museum Boltenianum, Part 2, pp. 156, 157, 1798, not Musculus Martyn, Universal Conchologist, Vol. 4, explanatory table of plates 151 and 152, 1787; not Musculus Rafinesque, 1818, nor Morch, 1853. Modiolaria Beck, in E. Robert, Zool. Voy. Recherche en Isl. et en Grbnl., pi. 17, figs. 1-4, 1838; Lov6n, Ind. Moll. Scand., p. 33, 1846; Stoliczka, Mem. Geol. Surv. India, Palseo. Indica, Vol. 3, p. 368, 1871; Tryon, Struct. Syst. Conch., Vol. 3, p. 264, 1884; Bucquoy, Dautzenberg and Dollfus, MoU. Mar. RoussiUon, Vol. 2, fasc. 4, p. 163, 1890; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 804, 1898. "Lanistes Humph." Swainson, Treat. Malac, pt. 2, p. 385, 1840, not Lanistes Montfort, Conch. Syst., Vol. 2, genus 122, 1810. Modiolarca J. E. Gray, Synop. Cont. Brit. Mus., Ed. 42, p. 151, 1840, misprint for Modiolaria, fide Sherborn, Index Animalium, Sect. 2, p. 4122, Aug., 1928. » Nautilus, Vol. 24, p. 10, 1911, figured in U. S. Nat. Mus., Bull. 112, pi. 1, figs. 1, 3, 1921. 254 San Diego Society of Natural History [ Memoirs Type {fide Stoliczka, 1871), Mytilus discors Linnjeus, figured by Reeve, Conch. Icon., Vol. 10, Modiolus, pi. 9, fig. 65, 1857. Shell rhomboidal, sculiitured by two rows (one on each side of a lateral area) of strise, which radiate from the beaks, leaving the middle portion smooth; umbones incurved, hinge edentulous or crenulated, with the hinge plate finely notched. Musculus Bolten being preoccupied by Thomas Martyn, Modiolaria Beck takes its place. There is some doubt as to .the year of issue of Beck's portion of the report of the Commission Scientifique d'lslande et de Gronland: Sherborn dates the genus 1838, while Bucquoy, Dautzenberg and Dollfus state that it appeared in 1846, the same year as Loven's Index of the Mollusks of Scandinavia, in which, likewise, Modiolaria is pro- posed. Lanistes cannot date from Humphrey,' 1797, and Swainson's use of that name is later than Montfort, 1810. A specimen of Modiolaria laevigata (Gray) is illustrated herewith, plate 12, figure 8. Modiolaria nigra (Gray) Modiola nigra J. E. Gray, Appendix Parry's Voy. 1819-20, p. ccxliv (nonwn nudein), 1824; Beck, Voy. de la Recherche, pi. 17, fig. 1, 18.")1. Modiolaria nigra Gray, Dall, 17th Ann. Rept. U. S. Geol. Surv., Part 1, p. 844, 1896; I. S. Oldroyd, Stanford Univ. Publ. Geo]., Vol. 1, p. 74, pi. 1.3, fig. 21, pi. .39, fig. 9, 1924. Musculus niger Gray, Dall, U. S. Nat. Mus., Bull. 112, p. 23, 1921. Miocene: Unga Island, Alaska (Dall, 1896). Recent: Arctic Ocean to Oregon; circumboreal (Dall, 1921). The fos.sil occurrence on Unga Island, Alaska, was attributed bj^ Dall to the Miocene. The age determination of late Tertiary faunas in extreme northern provinces is often difficult, and in the present case it is possible that the Unga Island occurrence is of Plio- cene age. Genus CRENELLA Brown, 1827 Crenella T. Brown, 111. Conch. Gt. Britain, Vol. 1, pi. 31, figs. 12-14, 1827; Ed. 2, p. 75, pi. 23, figs. 12-14, 1844; Harris, Cat. Tert. Moll. Brit. Mus., Pt. 1, p. 329, 1897; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 801, 802, 1898. Type (probably by monotypy-), Mytilus decussatus Montagu, 1808. Shell oval, or rhomboidal, surface ornamented by longitudinal and concentric stria; umbones incurved; cardinal border denticulate, the denticles ajjpearing to be the continuation of the crenula- tions on the margm of the valves; the single denticle present is also crenulated; interior of the valves nacreous. (Harris.) Crenella decussata (Montagu) Mytilus decussatus Montagu, Testacea Britannica, Supplement, p. 69, 1808. Crenella decussata Montagu, Forbes and Hanley, Hist. Brit. Moll., Vol. 2, p. 210, pi. 4.5, fig. 2, 18.53; Dall, U. S. Nat. Mus., Bull. 112, p. 24, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 79, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 6.5, Art. 22, p. 4, 1925. Type locality: Scottish coast; Recent. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd). Recent: Bering Sea to Puget Sound and south to San Pedro, California; also Atlantic. This is a minute shell with delicate radial striations. It is of infrequent occurrence as a fossil. C. divaricata d'Orbigny is probably a tropical race of this species. 1 Humphrey's genera are not accepted: moreover Sherborn states (Index .\nimaUum, section 1, p. 518) that he cannot find that word in Humphrey's work. - The first edition of Brown's "Illustrated Conchology of Great Britain" has not been available. The second edition contains only one species under Crenella, M. decussatus. under which reference is made to the first edition. For generic synonymy, see Dall, op. cit., pp. SOl-802, 1898. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 255 ORDER ANOMALODESMACEA Superfamily Laternulacea (=Ensiphonia Dall) Family PERIPLOMATIDAE Shell subnacreous, conspicuously inequivalve, nearly closed, edentulous; the resilium mternal, between two anteriorly or vertically directed chondrophores, often buttressed, the lithodesma rarely wanting ; ligament and area absent ; the beaks fissured, the pallial sinus broad and shallow. Animal with the siphons separated to their bases, naked and wholly retractile. (Dall.) Genus PERIPLOMA Schumacher, 1817 Periploma Schumacher, Es.s. Nouv. Syst. Habit. Vers Test., pp. llo, 116, pi. .5, fig. 1, 1S17. Type (by monotypy), Periploma inoequivalvis Schumacher, op. cit., p. 116, pi. 5, fig. 1, 1817. Shell oval or rounded; surface smooth or with faint growth lines; lithodesma present. This is a small genus of inequivalved shells. Cochlodesma Couthouy,' a genus of small, smooth, fragile shells, differs in its lack of the Uthodesma. Both Periploma and Cochlodesma have the chondrophore buttressed posteriorly. Periploma planiuscula Sowerby Plate 13, Figures la, lb Periploma planiusnila Sowerby, Proc. Zool. Soc. London for 1834, p. 87, 1834; Stearns, Proc. U. S. Nat. Mus., Vol. 13, pp. 223, 224, 1890; Williamson, Vol. 15, p. 184, 1892; Dall, Vol. 49, p. 447, 1915; Dall, U. S. Nat. Mus., Bull. 112, p. 24, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol, 1, p. 82, pi. 22, fig, 1, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Periploma lenlicularis Sowerby, Proc. Zool. Soc. London, p. 87, 1834. Periploma argentaria Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 238, pi. 18, fig. 8, 1837; Carpenter, Brit. .\ssn. Adv. Sci., Rept. for 1863, p. 638, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 258, 1888; Keep, West Coast Shells, p. 204, fig. 175, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 121, 122, 1903; NomJand, Univ. Calif. Publ. Geol., Vol. 10, table opp. p. 230, 1917. Periploma oblusa Hanley, lUustr. Lamarck's Shells, pi. 2, fig. 50, 1842. Anaiina alta C. B. Adams, Ann. Lye. Nat. Hist. N. Y., Vol. 5, p. 294 (pagination of the separate), 1852. Periploma excurva Carpenter, Proc. Zool. Soc. London for 1855, p. 229. Periploma exnirvata Carpenter, Brit. .Assn. Adv. Sci., Rept. for 1856, p. 287, 1857 (error for excurva). Shell ovate, thin, with incremental striae, and on the posterior portion of the valves obscure radial sulci; right valve more ventricose than left; chondrophore ovate-trigonal, its longer diameter directed forward obliquely and reinforced posteriorly Ijy an elongate rib-like buttress. Mature specimens measure 42 mm. in length and 26 mm. in altitude ; very large specimens attain a length of 52 mm. and an altitude of 35 mm. Type locality: Isla de Muerte, Guayaquil. Pliocene: Lower middle Etchcgoin, lower middle Pliocene of the Coalinga region (Nomland). Pleistocene: Rare in the lower San Pedro series of Deadman Island, Los Cerritos and Crawfish George's, Los Angeles County (Arnold); foot of 26th Street and at Spanish Bight, San Diego (Arnold; Mrs. K,, Stephens' MS.); upper Pleistocene at San Quintin Bay, Lower California, Mexico (E. K. Jordan). Recent: Point Conception, California, to Guayaquil. 1 Cochlodesma J. P. Couthouy. Boston Journ. Nat. History. Vol. 2, no. 2. p. 170, 1839. Couthouy placed "Anatina Leina Conrad" in this new genus, including "Mya prxlenuis Pennant" as a synonym of his type. Gray. 1847, fixed the type on Pennant's species. Cochlodesma has a smooth shell, the only sculpture being minute growth striae. "Cochlodesma" bainbridgeiisis Clark (Univ. Calif. Publ. Geol., Vol. 15. p. 86, pi. 13, figs. 3, 4, 1924) has strong concentric undulations suggestive of Cyathodonta. 256 San Diego Society of Natural History [ Memoirs This is the common Periploma of southern California. It is more elongate and heavier shelled than P. discus Stearns, and lacks the concentric sculpture of P. sulcata Dall. P. discus is truly disk shaped except that the posterior end of the valves is slightly produced into a short, broad, blunt rostrum. The known living range of P. discus Stearns is from San Pedro to San Diego. Section Halistrepta Dall, 1904 Halislrcpta Dall, Natuilus, Vol. 17, p. 123, March, 1904. Type (by monotypy), Periploma sulcata Dall. Shell with undulated sculpture. Periploma sulcata Dall Periploma sulcata Dall, Nautilus, Vol. 17, pp. 122, 123, March, 1904; Bull. 112, U. S. Nat. Mus., p. 25, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 83, pi. 40, fig. 6, 1924; E. K. Jordan, Proc. Calif. Acad. Sci. Ser. 4, Vol. 15, p. 244, 1926. Periploma (Halistrepta) sulcata Dall, Bull. Mus. Comp. Zool., Harvard College, Vol. 43, p. 427, pi. 15, fig. 10, 1908. Type specimen: In the U. S. National Museum. Type locality: San Pedro, California; Recent. Pleistocene: Upper Quaternary at San Quintin Bay, Lower California, Mexico (E. K. Jordan). Recent: San Pedro, California (Dall). This rare species is recognized by its strong, concentric undulations. Periploma clarki Nomland,' of the Santa Margarita upper Miocene near Coalinga, is based upon such a poor specimen that it is impossible to be sure from the figure that it is not a Macoma. Family THRACIIDAE Shell earthy and cellulo-crystalline, not pearly; inequivalve, thm, edentulous, often with a granular surface; the ligament and resilium chiefly external, posterior to the beaks, seated on pos- teriorly directed nymphae; cardinal area none; beaks entire or perforated by friction on each other; valves nearly closed; pallial sinus present. (After Dall.) Geologic range: Jurassic to Recent. This family is closely related to the Periplomatidce and the Laternulidw, and it would probably be a convenience to all conchologists to consider them as one family. Genus THRACIA Blainville, 1824 Rupicola Fleuriau, Journ. de Physique, Vol. 54, p. 345, 1802; not Rupicola Brisson, 1760, Aves. Thraria (Leach MS.) Blainville, Diet. Sci. Nat., Vol. 32, p. 347, 1824; Man. Malac, Vol. 1, p. 564, 1825, Vol. 2, p. 660, 1827; Gray, Proc. Zool. Soc. London for 1847, p. 191, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1522, 1523, 1903. Homeodesma Fischer, Man. Conchyl., p. 1171, 1887. Type {fide Gray, 1847), Thracia corbuloidea Blainville, op. cit., p. 347, 1824; figured in Kiener, Spec. G^n. Icon. Coq. Viv., Vol. 10, Thracia, p. 4, pi. 1, figs, la-d, and pi. 2, fig. 1, 1834, and by Reeve (as Thracia corbuloides Deshayes), Conch. Icon., Vol. 12, Thracia, pi. 1, fig. 1, 1859; Mediterranean. > Univ. Calif. Publ. Geol., Vol. 10. pp. 307, 308, pi. 19, fig. 6, 1917. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 257 Shell rather thin, often bluntly rostrate ; sculpture lacking or consisting of concentric striae, with or without concentric or oblique undulations, sometimes with fine granulations ; beaks generally in contact, and one or both perforated (usually the right) by contact with each other. Size up to 100 mm. in length, or more. Geologic range: Triassic to Recent. Subgenus THRACIA, s. s. Surface of valves smooth or with growth striae only. The typical subgenus differs from Cyathodonta in the lack of the obliquely concentric undulations so pronounced on Cyathodonta undulata Conrad, the type of Cyathodonta. Thracia trapezoides Conrad is very similar to T. corbuloidea Blainville, but the latter species is deeper (that is, higher from ventral margin to dorsal margin) and the rostration is more accentuated. Both species have imperfect right umbones, due to contact with the left beak. This imperfection of the right beak is typical of Thracia, s. s., but Cijathodonta has an entire right beak or but a small eroded hole on most specimens. The ligament of Cyathodonta is internal on a definite chondrophore, while the ligament of Thracia corbu- loidea and T. trapezoides is external. However, Thracia pubescens Pennant, a Mediter- ranean species, has an internal ligament resting on a perfectly definite chondrophore. It is much more elongate than corbuloidea. Thracia magnifica Jonas, of the Atlantic coast of Honduras, is a Cyathodonta, not very different from undulata Conrad except that it has a heavier shell and may average larger in size. Thracia (Thracia) trapezoides Conrad Plate 13, Figure 8 Thracia trapezoides Conrad, U. S. Expl. Exped., Geol., Vol. 10, p. 723, pi. 17, fig. 6a, 1849; Gabb, Geol. Surv. Calif., Palffio., Vol. 2, p. 90, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 267, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 122, 1903; I. S. Oldroyd, Nautilus, Vol. .32, p. 10.5, January, 1919; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta. pp. 1, 2, 27, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 84, pi. 43, fig. 8, 1924. Thracia trapezoidea Conrad, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 135, pi. 2, fig. 14, pi. 13, fig. 7, 1909; .\rnold and Hannibal, Proc. Amer. Phil. Soc, Vol. 52, pp. 581, 583, 584, 588, 590, 593, 596, 1913; Weaver, Washington Geol. Surv., Bull. 15, p. 18, 1912; Univ. Wash. Publ. Geol., Vol. 1, no. 1, pp. 28, .32, 1916; Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 239, 243, 254, 1916; Howe, Vol. 14, table opp. p. 92, 1922; WaterfaU, Vol. 18, pp. 78, 79, 1929. Type specimens: U. S. National Museum, No. 3,604. Type locality: Astoria, Oregon; Miocene. Oligocene: "San Lorenzo horizon of the Astor series (middle Oligocene)," below Porter, Washington; also "Seattle horizon of the Astoria series" south side of entrance to Blakeley Harbor, and at Restoration Point, Bainbridge Island, Washington; also "Twin River horizon of the .\storia series" in the sea cliffs west of Twin, Olympic Peninsula, Washington (Arnold and Hannibal); Oligocene of Snoho- mish County, of Kitsap County, and of Wah Kia Kum County, western Washington (Weaver). Miocene: Lower Miocene of Chehalis County, Washington (Weaver) ; Astoria Miocene (Dall) ; Empire for- mation of Oregon (Dall; Arnold and Hannibal; Howe); Montesano formation (Weaver). Pliocene: Eagle Prairie, Humboldt County (Cooper); Merced and Purisima formations of middle California (Arnold and Hannibal; Martin; etc.); upper Wildcat formation of northern California (Martin); Coos conglomerate of Coos Bay region, Oregon (Howe); Pico formation near Ventura (Waterfall). Pleistocene: "Pliocene" of Deadman Island, Los .\ngeles County (Arnold); ? "Pliocene," southeastern part of San Pedro (.\rnold). Recent: Puget Sound (I. S. Oldroyd, 1924) ; Craig, Prince of Wales Island, Alaska (G. Willett, coll.). This species is recognized by its rather short, broad rostration. The posterior ros- trated part of the valve is set off by a broad radial sulcation posterior to which is a low 258 San Diego Society of Natural History [Memoibs ridge radiating from the umbonal area to the posterior margin of the rostrum. The pos- terior dorsal area is laterally constricted. The average length is about 50 mm., height 40 mm. Thracia condoni Dall, described from Smith's quarry, near Eugene, Oregon, has been shown by Clark to be an Oligocene species. It has a wider rostration and appears to attain a larger average size. Martin' reported a Thracia from the Etchegoin (Pliocene) of the Sargent oil field, which he referred to as similar to T. condoni Dall ; but it is probably not Dall's species. Thracia (Thracia) jacalitosana Arnold Thracia jacalitosana Arnold, U. S. Geol. Surv., Bull. 396, p. 68, pi. 16, fig. 4, Jan. 15, 1910; Arnold and R. Anderson, Bull. 398, pi. 38, fig. 4, 1910. Type specimen: U. S. National Museum, No. 165,579. Type locality: On the Stone Canyon and Coalinga road, 200 yards north of Jacalitos Creek crossing, 14 miles southwest of Coalinga (Arnold). Pliocene: "Jacalitos formation," lower part of the Etchegoin formation, lower Pliocene, at the type locality. According to Arnold's description and figure, this is a very deep species, the anterior- posterior measurement (51 mm.) being unusually short in relation to the dorsal-ventral depth (44 mm.). The rostration is Ukewise short and deep. Thracia quentinensis Dall Thracia quentinensis Dall, West American Scientist, San Diego, Vol. 19, No. 3, p. 21, 1921; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 28, pi. 11, fig. 1, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In the U. S. National Museum. Type locality: San Quintin Bay, Lower California, Mexico; Pleistocene. "Shell more or less irregular, white, thin, strongly inflated, inequilateral, the beaks at about the anterior third; ends rounded, the posterior slightly compressed on the superior slope; surface minutely granulose, concentrically ir- regularly ridged or subundulate; base prominently arcuate; hinge feeble, pallial sinus short, rounded, free of the paUial line. Measurements of left valve: length, 47; height, 35; diameter, 12 mm." (Dall, 1921.) Dall described this species from a unique broken specimen. Jordan placed the age of the deposit as upper Quaternary. Thracia curta Conrad Thracia curia Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 248, pi. 19, fig. 8, 1837; Newcombe, Bull. Nat. Hist. Soc. Brit. Columbia, p. 44, 1893; Dall, Journ. Wash. Acad. Sci., Vol. 9, no. 1, p. 2, 1919; BuU. 112, U. S. Nat. Mus., p. 25, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 84, pi. 43, fig. 6, 1924; E. K. Jordan, BuO. So. Calif. Acad. Sci., Vol. 23, pt. 5, p. 153, 1924. Type locality: Near Santa Barbara, California; Recent. Pliocene: Late Pliocene of St. George Island, one of the Pribilof group (Dall, 1919). Recenl: Icy Cape, Arctic Ocean, Bering Sea, south to San Diego, California (Oldroyd); San Hipolito Point, Lower California, Mexico (in Hemphill Collection, Jordan). This is a small suboval shell lacking the prominence of rostration in trapezoides. Jor- dan gave its range as from San Hipolito Point, Lower California (based upon specimens > Univ. Calif. Publ. Geol., Vol. 9, p. 254, 1916. Volume 1 1 PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 259 in the Hemphill Collection at Stanford University), to Ecuador, but the southern Umit may be an error. In Volume 8 of the Proceedings of the Philadelphia Academy (p. 313, 1856) Conrad described a Thracia madropsis from the Tertiary of Monterey County. This was later figured in Volume 6 of the Pacific Railroad Reports (Geological Report, Chapter 2, pi. 2, fig. 3, 1857), but it does not seem to have been recognized by later writers. * Subgenus CYATHODONTA Conrad, 1849 Cyalhodonta Conrad, Proc. Acad. Nat. Sci. Phila., for 1S49, Vol. 4, pp. 155, 156, 1849. Type (by monotypy) , Cyathodonta undulata Conrad . Shell much like that of Thracia, s. s., but with prominent, obliquely concentric undulations. Thracia (CyathodontaJ undulata (Conrad) Plate 1.3, Figures 6a, 6b Cyathodonta undulata Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 4, p. 156, 1849; DaU, Proc. U. S. Nat. Mus., Vol. 49, p. 444, 1915; Nautilus, Vol. 32, p. 24, 1918; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 466, 1926; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 141, 1927. Cyathodonta granulosa Gould, Boston Journ. Nat. Hist., Vol. 6, p. 407, 1852, name only. ? Cyathodonta dubiosa Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 445, 1915, no figure; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 86, pi. 9, fig. 5, 1924. ? Cyathodonta pedroana Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 445, 1915, no figure; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 86, pi. 54, figs. 1, 2, 3, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 4, 1925. "Subovate, inequilateral, very thin and fragile, with obliquely concentric undulations, profound on the anterior side, and suddenly becoming obsolete towards the posterior extremity, which is truncated and direct; posterior slope of the deeper valve obscurely tricarinated ; cartilage pit robust; valves with minute, very closely arranged, granulated radiating lines, iVio^l nearly." (Conrad.) Pliocene: Coyote Mountain, western Imperial County (Hanna); Santa Antonita Point, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (as C. pedroana Dall, T. S. Oldroyd) ; upper Pleistocene at Magdalena Bay, Lower California, Mexico (Dall). Recent: Catalina Island (as C. pedroana Dall) and San Pedro to west Mexican coast. This species was described by Conrad, without figure, along with several other forms stated to have come from "the coasts of Lower California and Peru." The shells we have seen from San Pedro and San Diego labeled C. undulata seem to fit Conrad's description of that species. These specimens indicate that considerable variation in the shape of the valves and in the character of the concentric ripples is the rule in this group and we do not beUeve that the distinctions Dall has used for the separation of dubiosa and pedroana as full species are significant. Thracia (Cyathodonta) plicata Deshayes (Encycl. Meth. Vers, Vol. 3, p. 1039, 1832) as figured in Kiener's Iconographie (Vol. 11, Thracia, pi. 2, fig. 3) is more elongate than the San Diego shells assigned to undulata. Thracia (Cyathodonta) formosa Nomland Thracia formosa Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 234, pi. 9, figs. 4, 4a, April 19, 1917. Type specimen: University of California collection, No. 11,103. Type locality: On Zapato Creek, Fresno County; middle Pliocene. Pliocene: "Pecten coalingensis zone," middle Etchegoin, middle Pliocene, on Zapato Creek, Fresno County (Nomland). 260 San Diego Society of Natural History [Memoirs From Nomland's figure this species seems to be similar to T. (Cyathodonta) undulata Conrad. The concentric ripples are perhaps finer and closer together than on Conrad's species. The "tooth" mentioned by Nomland must be the cartilage pit if the shell is a Thracia, but we have not seen the type. Superfamily Pandoracea (=Adelosiphonia Dall) Family PANDORIDAE Shell compressed, rather flat, inequivalved, free, nacreous with a thin external prismatic layer; dorsal edges of the valves overlapping, not socketed, with crural ridges or teeth on either side of the resilium; ligament external or obsolete; resilium internal, posterior to the beaks, with or without a lithodesma; cardinal area, none; valves closed, beaks not perforated by contact with each other; pallial line simple. Genus PANDORA Hwass in Chemnitz, 1795 Pandwa Hwass, Chemnitz, Neues Syst. Conchyl. Cab., Vol. 11, p. 211, 1795, Tellina inxquivalvis included; Bruguiere, Encycl. Meth., Vers, liv. 2, p. 250, 1797; Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 88, 1799; Schu- macher, Ess. Nouv. Syst. Hab. Vers Test., p. 114, 1817; Children, Quart. Jour. Sci., Lit., Arts, p. 302, January, 1823; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1515, 1516, 1903. Type (by subsequent designation. Children, 1823), Tellina incequivalvis Linnseus {Solen inaquivalms Linnseus, 1758; Pandora roslrata Lamarck). Shell closed, rather flat, inequivalved, the right valve flat or but little convex and frequently overlapped on its ventral margin by the left valve ; posterior portion of valves somewhat attenuated ; hinge with diverging cardinal, crural ridges or teeth; shell substance pearly with prismatic layer outside. Size small, up to about 50 mm. in length. Geologic range: Cretaceous to Recent. Distribution: Widely distributed in cold and temperate waters. Volume 11 of Chemnitz is accepted as binomial by many writers who do not accept the rest of Chemnitz. The whole work is entitled to consideration as a binary work in the technical sense of the International Commission on Zoological Nomenclature, though it is not binomial. Dating Pandora from Bruguiere, 1797, would not change its application, for its type (by monotypy) would be Pandora margaritacea Lamarck, a variety of incequivalvis {fide Stewart).' Section Pandora, s. s. Right valve with two cardinals ; left valve with one obscure cardinal or none ; lithodesma absent ; right valve with feeble concentric sculpture. The typical section is not represented in the Neocene or Quaternary of California. Section Kennerlia Carpenter, 1864 Kennerlia. Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, pp. 602, 638, 1864; Proc. Zool. Soc. London, p. 602, 1864; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1517, 1903. Type (by subsequent designation, Dall, 1903), K. filosa Carpenter. Like Pandora, s. s., but with a lithodesma; right valve with fine but widely spaced and somewhat irreguhxr ratlial striae. The radial striations on these shells are wide apart, sometimes discontinuous, and much resemble cracks in chinaware. For the section name we have returned to the original spelling of Carpenter. 1 Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 303, 1930. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 261 Pandora filosa (Carpenter) Kennerlia filosa Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 602, 638, 1864; Proc. Zool. Soe. London, pp. 602, 603, 1864. Pandora filosa Carpenter, Sowerby, Reeve's Conchologia Iconica, Vol. 19, Pandora, pi. 2, figs. lOa-6, 1874. Pandora (Kennerlia) filosa Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 124, pi. IS, fig. 3, 1903; Dall, Bull. 112, U. S. Nat. Mus., p. 26, 1921. Kcnnn-lyia fdosa Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 449, 1915. Pandora (Kennerlyia) fdosa Carpenter, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 88, pi. 33, figs. 2a, 2b, 1924. Type locality: Puget Sound; Recent. Pleistocene: Lower San Pedro series of Deadman Island, one right and one left valve (Arnold). Recent: Nvniivak Island, Bering Sea, to San Pedro, California. This is a small elongate species, measuring about 22 mm. in length and 10 mm. in height. The posterior end is definitely attenuated into a rostrum. The posterior dorsal margin is approximately straight, below which, on the right valve only, there are generally one or two radial sulcations nearly parallel but diverging slightly from the margin. The anterior dorsal margin is straight or but slightly convex and about one third the length of the posterior margin. The left valve is ventricose, irregularly undulating; the right valve being flat and radially sculptured on its exterior prismatic layer. Pandora bilirata Conrad Pandora bilirata Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 7, p. 267, 1855; U. S. Pacific R. R. Repts., Vol. 6, Geological Report, p. 73, pi. 5, fig. 25, 1857. Kennerlia bicarinata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 638, 1864; Proc. Zool. Soc. London, 1864, p. 603; Tryon, Struct. Syst. Conch., Vol. 3, p. 143, 1884. Pandora (Kennerlia) bicarinata Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 123, pi. 18, fig. 2, 1903. Pandora (Kennerlyia) bilirata Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 449, 1915; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 89, pi. 53, figs. 8, 9, 1924. Pandora (Kennerlia) bilirata Conrad, Dall, U. S. Nat. Mus., Bull. 112, p. 26, 1921. Oblong, very inequilateral, contracted anteriorly, convex medially; posterior side with two dis- tinct, carinated lines toward the hinge margin which is straight and not oblique; posterior extremity trimcated. Length, 15 mm.; height, 6 mm. (Conrad.) Pleistocene (or Pliocene ?): Of Santa Barbara (Conrad, 1857). Pleistocene: Lower San Pedro series of Deadman Island, one left valve (Arnold). Recent: Forrester Island, Alaska, to Point Abreojos, Lower California. This species differs from P. filosa by the rounded posterior margin, which in filosa is rostrated. The beaks are also nearer the middle in bilirata. Pandora grandis Dall Plate 13, Figures 5a, 5fe Pandora (Kennerlia) (p-andis Dall, "Proc. Calif. Acad. Sci., Vol. 7, p. 5, 1877," unauthorized separate'; Dall, Bull. 112, U. S. Nat. Mus., p. 25, 1921. Kennerlyia grandis Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 448, 1915. Pandora grandis Dall, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. Pandora (Kennerlyia) grandis Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 448, 1915; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, pp. 87, 88, pi. 15, fig. 10, 1924. Type specimen: U. S. National Museum, Cat. No. 171,069. Type locality: Unalaska. • This separate was never included by the California Academy in their Volume 7. In their hurry to describe new species both Stearns and Dall resorted to the private publication of leaflets, without illustrations, which were stated to be from the Proceedings of the California Academy of Sciences but which never were. These fragile, easily destroyed, and now rare leaflets are an annoyance to those who attempt to work from original sources. 262 San Diego Society of Natural History [ Memoirs Miocene: St. Paul Island, Alaska (Dall, 1896). Pliocene: Lower part of the Merced formation, Seven Mile beach just south of San Francisco, San Mateo County, and upper division of the Wildcat series, Humboldt County (Martin, 1916). Pleistocene: Santa Monica, Los Angeles County (Dall, 1915). Recall: Pribilof Islands, Bering Sea, to Siletz Bay, Oregon (Dall, 1921). This species is easily recognizable by its large size, curved dorsal margin and lack of rostration. Length, 55 mm. ; height, 38 mm. Pandora glacialis Leach Pandora glacialis W. E. Leach, in J. Ross, Voy. Discov. Baffin's Bay, Ed. 2, 8vo, Appen. 4, p. 174, July, 1819; Sowerby, Reeve's Conch. Icon., Vol. 19, Pandora, .sp. 14, pi. 2, figs. 14a-b, 1874. Pandora (Kennerlyia) glacialis Leach, Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 448, 1915; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 89, pi. 42, figs. 3, 4 (pi. 15, fig. 11 ?), 1924. Pandora (Kennerlia) glacialis Leach, Dall, Bull. 112, U. S. Nat. Mus., p. 26, 1921; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type locality: Greenland seas; Recent. Pliocene: Pico formation (upper Pliocene part), near Ventura (Waterfall). Recent: Arctic Ocean and south to Fuca Straits; also Atlantic (Dall, 1921). This species is well figured in Reeve's "Conchologia Iconica." According to these figures, the right valve has two or three posterior radial plications and a broad sulcation ventral to them. The only fossil record in California is that of Waterfall. Section Heteroclidus Dall, 1903 Heteroclidus Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1518, October, 1903. Type (by original designation), Clidiophora punctata Conrad, = Pandora punctata Conrad. Left valve with the posterior cardinal crural ridge or tooth absent; right valve with a short posterior cardinal and a produced anterior cardinal ridge; both the anterior ridges, or teeth, ending in front of the anterior adductor scar; Uthodesma present. Pandora punctata Conrad Plate 13, Figures 2a, 2b Pandora punctata Conrad, Jour. Acad. Nat. Sci., Phila., Vol. 7, p. 228, pi. 17, fig. 1, 1837; Sowerby, Reeve's Conch. Icon., Vol. 19, Pandora, sp. 13, pi. 2, fig. 13, 1874; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 219, 1917; Jordan, Proc. Calif. Acad. Sci., Ser. 4, p. 244, 1926. Clidophora punctata Conrad, Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 90, 1868-9. Clidiophora punctata Conrad, Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 235, 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 183, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 124, 1903; Arnold, U. S. Geol. Surv., Bull. 396, p. 160, pi. 27, fig. 10, January, 1910; Arnold and Anderson, Bull. 398, p. 335, pi. 49, fig. 10, 1910; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Pandora {Heteroclidus) punctata Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1521, 1903; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 90, pi. .53, figs. 6, 7, 1924. Pandora (Heteroclidus) punctatus Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 450, 1915; Bull. 112, U. S. Nat. Mus., p. 26, 1921; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Tandora (Clidiophora) punctata Conrad, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. ? Miocene: Ventura County (Gabb, 1868-9; Cooper, 1888 = ? var. gabbi Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1521, 1903, possibly not Miocene). Pliocene: Etchegoin formation of Coalinga region (Arnold and R. Anderson, 1910; Nomland, 1917); upper Sargent or Merced formation of the Sargent oil field, near Sargent, San Benito County (? Cooper; Nomland; Martin); Purisima formation along the coast south of Halfmoon Bay, middle California (Martin). Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 263 Pleistocene: Lower San Pedro series of Deadman Island, rare; Spanish Bight, North Island, San Diego; upper San Pedro series of San Pedro (,\rnold, 1903) ; upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan); numerous localities in the "Saugus" or Las Posas zone near and east of Ventura (Waterfall; also collected by the present authors). Rfccnl: Vancouver Island to the Gulf of California (Dall, 1921). This species is readily recognized by its strongly curved (concave) posterior dorsal margin and the small punctations on the inner surface of the valves. The anterior dorsal margin is short and evenly curved to the ventral margin. Fossil specimens are frequently about 40 mm. in length. The "Miocene" occurrence of this species is based on the records of Gabb and Cooper. It is probable that their Miocene is now regarded as Pliocene, but lack of exact locality data makes it impossible to determine definitely. The form without punctations from this "Miocene," which Dall has named variety gabbi, has not been recognized by us in the collections available. Family LYONSIIDAE Shell inequivalve, thin, sub-nacreous, edentulous; ligament obsolete, the resilium internal, uniting the edges of a long, mesial lithodesma to a narrow chondrophoric sub-marginal ridge on each valve; beaks entire, valves nearly closed, pallial sinus distinct. (Dall.) Genus LYONSIA Turton, 1822 Lyonsia W. Turton, Conchylia Insularum Britannicarum, pp. xvii and 34, 1822; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 635, 1846; Gray, Proc. Zool. Soc. London, Pt. 15, p. 191, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1513, 1514, 1903. Type (by monotypy), Mxja striata Montagu, 1822 = Mya noricegica Gmelin, 1790 = Mya norvegica Chemnitz, Neues Syst. Conch. Cab., Vol. 10, p. 345, pi. 170, figs. 1647 and 1648, 1788; also figured by Forbes and Hanley, Hist. Brit. Moll., Vol. 1, p. 214, 1853, Vol. 4, pi. 8, figs. 6-9; west coast of Ireland, Recent.^ Shell rather small, thin, internally nacreous; valves unequal, elongate, posterior distally trun- cated; sculpture consisting of radial striations. Geologic range: Tertiary to Recent. Distribution: Coasts of Europe, Greenland, North America, etc. This genus has a number of synonyms, some of which are referred to by Gray, Dall, and others. Lyonsia califomica Conrad Lyonsia califonnca Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 248, pi. 19, fig. 20, 1837; Keep, West Coast Shells, p. 202, fig. 174, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 125, 1903; Keep, West American Shells, p. 99, fig. 88, 1904; Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 453, 1915; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 252, 1916; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 261, pi. 18, fig. 3, 1918; Dall, Bull. 112, U. S. Nat. Mus., p. 26, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 91, pi. 27, fig. 3, 1924; T. S. Oldroj-d, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 4, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: V. S. National Museum, No. 253,111. Type locality: Near Santa Barbara, California; Recent. ' Dall (Proc. U. S. Nat. Mus., Vol. 49, p. 452. 1915) separates L. striata (Montagu) specifically from L. norvegica (Gmelin). These forms are so close, however, that the conception of the genus is not influenced whether the one or the other is taken as type. 264 San Diego Society of Natural History [Memoirs Pliocene: Middle part of the Wildcat formation, Humboldt County (Martin). Pleistocene: "Pliocene" of Deadman Island, also lower San Pedro series of Deadman Island and San Pedro (Arnold, 1903); lower San Pedro fauna of Nob Hill cut in San Pedro (T. S. Oldroyd); Pleistocene of San Diego (in Oldroyd Collection) ; upper San Pedro series of Deadman Island, Crawfish George's, and San Pedro (Arnold, 1903); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Puget Sound to Manuel's Lagoon, Lower California, Mexico. This is an elongate-ovate shell with the posterior portion slightly attenuated. It has delicate radial sculpture. Lyonsia arenosa (Moller) Pandorina arenosa H. P. C. Moller, Index MoUuscorum Groenlandise, p. 20, 1842; Gray, Zool. Beechey's Voy. to the Pacific, etc., pi. 43, fig. 3, 1839. Lyonsia flabellala Gould, Otia Conch., p. 162, 1861. Lyonsia arenosa Moller, Dall, IT. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896; Trans. Wagner Inst. Sci., Vol. 3, p. 1514, 1900; Proc. U. S. Nat. Mus., Vol. 49, p. 453, 1915; U. S. Nat. Mus., Bull. 112, p. 26, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. I, p. 92, 1924. Miocene: Miocene of St. Paul Island, Alaska (Dall, 1S96). Pleistocene: Leda clays of the Pleistocene in Maine, New Brunswick and Quebec (Dall, 1900). Recent: Arctic Sea to Japan and the Okhotsk Sea on the west, and on the east to the Aleutians and Kodiak Island, Alaska; also North Atlantic. According to Dall, this is a short and solid species well distinguished from any others. Genus MYTILIMERIA Conrad, 1837 Mytilimeria Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, pp. 246, 247, pi. 19, fig. 5, 1837, M. nuttallii only species; Tryon, Struct. Syst. Conch., Vol. 3, p. 147, 1884. Type (by monotypy), Mytilimeria nuttallii Conrad, California, Recent and fossil. Shell rounded-oval, more or less ventricose, equivalve, fragile, covered by a thin caducous epi- dermis; beaks subspiral; hinge without teeth, but formed of small linear excavations under the beaks to receive the ligament, which contains a small ossicle; muscular impressions small, jiallial impression with an obtuse sinus. (Tryon.) Mytilimeria nuttallii Conrad Mytilimeria nuttallii Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 247, pi. 19, fig. 5, 1837; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 540, 601, 638, 1864; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 90, 1868-9; Tryon, Struct. Syst. Conch., Vol. 3, p. 147, pi. 108, fig. 68, 1884; Cooper, 7th Ann. Rept. Calif. St. Mineralo- gist, p. 252, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 126, pi. 17, fig. 8, 1903; Keep, West American Shells, p. 100, 1904; Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 456, 1915; Bull. 112, U. S. Nat. Mus., p. 27, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 94, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 4, 1925. Type specimen: U. S. National Museum, No. 74,234. Type locality: California; Recent. Shell suboval, inflated, thin, fragile; white, with a very tliin, yellowish, deciduous epidermis. (Conrad.) ? Miocene: Tomales (Gabb). Pleistocene: "Pliocene" of Deadman Island, rare; lower San Pedro series of Deadman Island, rare, and of San Pedro (Arnold); lower San Pedro series of Nob Hill cut, San Pedro (Oldroyd, 1925). Recent: Vancouver Island to Round Island, Lower California, Mexico (Jordan). There does not seem to be any later confirmation of Gabb's Miocene record of this species. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 265 Superfamily Poromyacea Family CUSPIDARIIDAE Shell sub-cquivalve, rostrate, earthy or fellulo-crystalUne, rarely with surface granulations; hinge edentulous or with sub-umbonal tutierculation, sometimes buttressed; ligament sub-internal, anterior to the beaks or obsolete; resilium internal, with a mesial or ventral lithodesma; cardinal area amphidetic or obscure; valves closed except at the tip of the rostrum; pallial line simple; siphons united. (Dall.) Genus CUSPIDARIA Nardo, 1840 Neiera. Gray, in Griffith's Cuvier, legend to pi. 21, fig. 5, 18.34; not Neai^-a Robineau-Desvoidy, 1830. Cuspidaria G. D. Nardo, Atti. Riun. Sci. Ital., Vol. 1, p. 175, 1839 (1840); .^n. Sci. Lomb. Ven., Vol. 10, p. 50, 1840; Dall, Bull. Mils. Conip. Zool., Harvard Coll., Vol. 12, no. 6, pp. 292-294, 1886; Proc. U. S. Nat. Mus., Vol. 12, p. 279, 1889; Trans. Wagner Inst. Sci., Vol. 3, pp. 1503, 1504, 1903. Type ( fide Dall, 1886), TelUna euspidata Olivi, Zool. Adriatica, p. 101, 1792; Adriatic; Recent ; also reported from the Miocene of Baden, near Vienna. Shell concentrically sculptured; hinge with a small posteriorly inclined chondrophore in each valve, and an elongate ridge behind it; ligament when present always anterior to the beaks. (Dall.) Geologic range: Jurassic to Recent. Distribution: All seas; abundant in deep water. Subgenus CUSPIDARIA, s. s. Valves smooth or concentrically feebly sculptured, fossette posteriorly inclined and attached to the hinge margin by its posterior edge; one posterior lateral tooth in the right valve. (Dall, 1903.) Subgenus CARDIOMYA A. Adams, 1864 Cardiomya A. Adams, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 3.30, 1864. Type (by monotypy), Neoera gouldiana Hinds; Japanese seas; Recent. Like Cuspidaria, s. s., but with radial sculpture and more vertical and prominent fossette. Cuspidaria (Cardiomya) pectinata (Carpenter) Plate 1, Figures 16, 17 Nexra -pectinata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 602, 637, 1864; Proc. Acad. Nat. Sci. Phila. for 1865, p. 54; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 181, pi. 18, fig. 11, 1903. Cuspidana pectinata Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 28, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 101, 1924. Type locality: Puget Sound. Pleistocene: Lower San Pedro series at Deadman Island, Los Angeles County, "one valve" (Arnold). Recent: Puget Sound, British Columbia to Panama Bay (Oldroyd). This little shell is obtained by dredging along the southern California coast. Mrs. I. S. Oldroyd has dredged many specimens in ten or twelve fathoms in Puget Sound. The species is rare as a fossil. The subgenus Cardiomya is well represented in the Eocene of California. Family VERTICORDIIDAE Shell ecjuivalve or nearly so, variable in shape, valves closed; hinge with a strong tooth m the right valve anterior to the resilium, and dorsal margins modified to overlap each other; ligament obsolete, resilium posterior to the beaks, with a lithodesma; pallial hne entire or with a shallow sinus. (After Dall.) 266 San Diego Society of Natural History [ Memoirs Genus VERTICORDIA S. Wood in Sowerby, 1844 Verticordia J. E. Gray, Synopsis of the Contents of the British Museum, Ed. 42, p. 150, 1840, nude name, Ed. 44, p. 80, practically a nude name;^f/e Iredale, Proc. Malac. Soc. London, Vol. 10, pp. 299, 309, 1913. Verticordia S. Wood in Sowerby, Min. Conch. Gt. Brit., Vol. 7, p. 67, pi. 1139, 1844; Dall, Trans. Wagner Free Inst. Sci., Vol. 3, p. 1509, 1903. Type (by monotypy), Verticordia cardiiformis J. Sowerby; England, Pliocene. Shell small, nacreous, beaks strongly prosogyrous; sculpture consisting of radial ribs. Verticordia omata (d'Orbigny) Plate 13, Figure 4 Trigonulina ornata d'Orbigny, in R. de la Sagra, Hist. Phys. Polit. et Nat. Cuba, Moll., Vol. 2, p. 292, pi. 27, figs. 30-33, 1846. Hippagus 7ioile, the basal margin flat and entire. Shell without a lunula but with a long excavated escutcheon; the ligament deep-seated but practically external. Hinge in the right valve with a A-shaped socket and a triangular cardinal tooth below it, behmd which is a short, feeble, narrow, lateral tooth; in the left valve a A-shaped cardinal and ]30S- terior lateral. The teeth become more or less obsolete in old shells. The mantle edge is minutely frmged, the siphonal openings papillose, the foot stout, blunt, ovate cylindrical. The shell is earthy in texture. (Dall.) Calyptogena pacifica Dall Plate 13, Figures 13a, 136 Calyptogena pacifica Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 190, 1891; Vol. 17, p. 713, pi. 25, figs. 4, 5, 1894; Proc. Acad. Nat. Sci. Phila. for 1902, p. 712, Jan., 1903; Trans. Wagner Inst. Sci., Vol. 3, p. 1435, 1903; U. S. Nat. Mus., Bull. 112, p. 32, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 116, 1924. , Volume I] PLIOCENE AND PLEISTOCENE MOLLTJSCA OF CALIFORNIA 279 Type specimen: In the U. S. National Museum. Type locality: Off Dixon Entrance, Alaska, in 322 fathoms. Pliocene: Los Angeles, California (Dall, 1903) ; blown out of big Amalgamated Gas well, from depth of 2500 feet with Dendraster inlerlineatus Stimpson, Wolfskill lease, Salt Lake oil field, near Beverly Hills, Los Angeles County (coll. by J. O. Lewis, 1912). Recent: Clarence Strait, Alaska, to Santa Barbara Channel, California (Dall, 1921). In shape this species resembles somewhat a Petricola. It is elongate, with an anterior, moderately prominent beak. There is no sculpture except growth lines. C. elongata Dall' is more elongate, compressed, and thinner shelled. It is the southern form of the type species, and should probably be listed as a variety. Superfamily Chamacea Family CHAMIDAE Shell inequivalve, thick, attached or free m young or adult stages; beaks subspiral; ligament external; adductor impressions large, reticulated, pallial line simple. Geologic range: Cretaceous to Recent (Odhner). Genus CHAMA Linnaeus, 1758 Chama Linnaeus, Syst. Nat., Ed. 10, p. 691, 1758; Children, Quart. Jour. Sci., Lit., Arts. Vol. 15, p. 28, pi. 1, fig. 74, April, 1823; Odhner, Kungl. Vetens. Handl., Vol. 59, No. 3, 1919. Type (by subsequent designation, Children, 1823), Chavia lazarus Linnaeus, figured by Reeve, Conch. Icon., Vol. 4, Chama, pi. 2, figs. Aa-b, 1846. Shell attached by the left valve, which is generally the larger; adductor impressions large; sculp- ture foliaceous or spuiose. The hinge teeth in this genus are only observable in the young stages ; later they are replaced by rather crude and heavy rugosities arranged nearly parallel to the hinge mar- gin. Chama pellucida Broderip Chama ■pellucida Broderip, Proc. Zool. Soc. London, Vol. 2, p. 149, 1835; Trans. Zool. Soc. London, Vol. 1, p. 302, pi. 38, fig. 3, 1835; Reeve, Conch. Icon., Vol. 4, Chama, sp. 32, pi. 6, fig. 32, 1847. Chama pellucida Sowerby, Keep, West Coast Shells, p. 182, fig. 155, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 189, 1892; Cooper, Calif. State Mining Bureau, Bull. 4, p. 24, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 130, 1903; Keep, West Amer. Shells, p. 59, fig. 46, 1904; Arnold, U. S. Geol. Surv., BuU. 396, p. 158, pi. 26, figs. 5, 6, January 15, 1910; Arnold and R. Anderson, BuU. 398, pp. 125, 332, pi. 48, figs. 5, 6, 1910; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 417, 1914; Odhner, Kungl. Svensk. Vetenskaps-akad. Handl., Vol. 59, No. 3, p. 62, 1919; Dall, U. S. Nat. Mus., Bull. 112, p. 33, Feb. 24, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol, Vol. 1, p. 118, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Miocene: Lower San Pablo of middle California (Clark, 1914). Pliocene: Pliocene of Ventura County (Stephen Bowers) ; upper Etchegoin of Coalinga region (Arnold and R. Anderson) ; common in Pcclen coalingensis zone of the Etchegoin formation (Nomland) ; upper Pico near Ventura (Waterfall). Pleistocene: Lower San Pedro series of Deadman Island, Los Angeles County (Arnold, 1903) ; lower Quater- nary at Magdalena Bay, Lower California, Me.xico (Jordan, 1924); rare in the upper San Pedro of San Pedro, Deadman Island, Los Cerritos, and Crawfish George's, Los Angeles County (Arnold, 1903); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Oregon to Chile and the Galapagos Islands (Dall, 1921). This is the common California Chama. 1 Proc. U. S. Nat. Mus., Vol. 52. p. 408, 1916, figured in Bull. 112, U. S. Nat. Mus., p. 23, pi. 3. fig. 3, Feb. 1921. 280 San Diego Society of Natural History [ Memoirs Chama frondosa Broderip Chama frondosa W. J. Broderip, Proc. Zool. Soc. London, Vol. 2, p. 148, April, 1835; Trans. Zool. Soc. London, Vol. 1, p. 302, pi. 38, fig.s. 1, 2, 1835; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 262, 1909; Lamy, Jour. Conchyl., Vol. 57, p. 236, 1909; Bull. 112, U. S. Nat. Mus., p. 33, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 118, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 463, 1926; E. K. Jordan, Vol. 15, p. 427, pi. 34, fig. 1, 1926. Chama parasitica de Rochebrune, Bull. Mus. Hist. Nat. Paris, Vol. 1, p. 243, 1895, fide Lamy, 1909. Type specimen: In the British Museum. Type locality: Island La Plata, West Colombia. Pliocene: Coyote Mountain, western Imperial County (Hanna); Pliocene of Cedros Island and of Turtle Bay, Lower California, Mexico (Jordan and Hertlein). Recent: San Diego, California, to Peru. This is a larger species than Chama pelhicida. Chama buddiana C. B. Adams Chama buddiana C. B. Adams, Annals of Lyceum of Natural History of New York, ^'ol. 5, p. 253 (of the separate), 1852; Dall, Bull. 112, U. S. Nat. Mus., p. 33, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 119. 1924; E. K. Jordan, Proc, Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In the collection at Amherst College. Type locality: Panama; or Guaymas, Mexico; Recent. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Panama. Described as having small, thick, dentiform white spines. The specimens we have examined have been worn and lack the projecting spines. Genus ECHINOCHAMA Fischer, 1887 Echinochama Fischer, Man. Conchyl., p. 1049, 1887; Woodring, Carnegie Inst. Publ., No. 366, p. 105, 1925. Type (by monotypy), Chama arcinella Linnaeus; West Indies, Recent and fossil. Young shell attached by right valve; adults not attached. Woodring (1925) has stated that Echinochama is a strictly American tropical group of Chamas. On the Pacific coast the genus is represented by Echinochama californica Dall, which occurs in the Recent fauna of the Gulf of California and at Cedros Island. In the Caribbean region the genus first appears in the lower Miocene (Cercado formation of the Dominican Republic). The genotype, E. arcinella (Linnseus), lives in the West Indies. Echinochama Fischer differs from Chama Linnaeus in that the shell is attached by the right valve in early stages and when adult is not attached. The right valve often shows a place where it was originally attached. The umbones being strongly prosogyrous, the right and left valves are readily distinguished. Genus PSEUDOCHAMA Odhner, 1917 Pseudochama Odhner, Kungl. Svenska Vetenskaps-akademiens Handlingar, Vol. 52, No. 16, pp. 28-31, 1917; Vol. 59, No. 3, pp. 20, 23, 1919. Typical example^: Pseudochama cristella (Lamarck) ; Australian waters; Recent. Shell attached by the right valve; not free in adult stage. 1 The original description of Pseudochama Odhner. 1917. has not been seen by the authors. P. cristella Lamarck is in Odhner's original list. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 281 Pseudochama exogyra (Conrad) Chama exogyra Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 2.56, 18.37; Reeve, Conch. Icon., Vol. 4, Chama, sp. 38, pi. 7, fig. 38, 1847; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 233, 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 189, 1892; Cooper, Bull. Calif. State Mining Bureau, No. 4, p. 24, 1894; .\rnold, Mem. Calif. Acad. Sci., Vol. 3, p. 130, 1903; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. I, p. 119, 1924. Pseudochnma exogyra Conrad, Dall, U. S. Nat. Mus., Bull. 112, p. 33, 1921; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type locality: Santa Barbara, California; Recent. Plioceiie: Upper Pico, Santa Barbara horizon, upper Pliocene, near Ventura (Waterfall). Pleistocene: Santa Barbara to San Pedro (Cooper); upper San Pedro series of San Pedro and Los Cerritos (Arnold); San Nicholas Island (Bowers). Recent: Oregon to Panama. This species has lower, shorter sculpture than C. pellucida and is generally larger and heavier shelled. It is further distinguished by being attached by the right valve. Collec- tions usually contain only specimens that had become loose and were subjected to erosion before being found. Superfamily Codakiacea Family THYASIRIDAE Valves equal, free, closed, with a posterior radial flexure; hinge edentulous or with an obscure right cardinal; ligament and resilium behind the beaks, sub-external; pallial Ime entire. Genus THYASIRA Leach in Lamarck, 1818 Thyasira Leach MS., Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 492, 1818; DaU, Trans. Wagner Free Inst. Sci., Vol. 3, pp. 1335-1338, 1903. Cmchocele Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 27, 1866. SckizothsTus Locard, Ann. Univ. Lyons, p. 180, 1896; not of Conrad, 1853. Type (by monotypy, fide Dall, 1903), Tellina flexuosa Montagu, 1803 (figured by Forbes and Hanley, Hist. Brit. Moll., Vol. 2, pp. 54, 55, pi. 35, fig. 4, 1852). Smooth, thin-shelled, typically small. Geologic range: Cretaceous to Recent. Conchocele Gabb, based upon Thyasira disjuncta (Gabb), differs from Thyasira only in the size of the respective type species. Thyasira bisecta (Conrad) Compare Plate 13, Figure 15 Vemis bisecta T. A. Conrad, U. S. Expl. Exped. (Wilkes), Vol. 10, Geol., p. 724, October, 1849, Geol. Atlas, pi. 17, figs. 10, 10a, 1849. Cyprina bisecta Conrad, Amer. Jour. Conch., Vol. 1, p. 153, 1865. Conchocele disjimcta Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 28, 1866, p. 99, pi. 7, figs. 48a-b, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 236, 1888. Conchocele bisecta Conrad, Gabb, loc. cit., p. 99, 1868-9. "Cryptodon bisectus Dall," DaU, Proc. U. S. Nat. Mus., Vol. 14, p. 189, 1891; Vol. 17, p. 713, pi. 26, figs. 2, 5, 1895. Thyasira bisecta Conrad, Dall in Spurr, U. S. Geol. Surv., 20th Ann. Rept., Pt. 7, p. 264, 1900; Dall, Proc. U. S. Nat. Mus., Vol. 23, pp. 789, 790, 1901; -Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 135, pi. 15, fig. 4, 1903; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 118, 1909; Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 180, pi. 1, fig. 7, 1909; Weaver, Wash. Geol. Survey, Bull. 15, p. 18, 1912; DaU, U. S. Nat. Mus., Bull. 112, p. 33, 1921; Dall, Amer. Jour. Sci., Ser. 5, Vol. 4, p. 306, 1922; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 120, pi. 10, fig. 1, 1924; Yabe and Nomura, Science Repts. Tohoku Imper. Univ., Ser. 2 (Geol.), Vol. 7, No. 4, p. 84, pi. 33, figs. 2, 7-10, 1925; Hiigg, BuU. Geol. Inst. Upsala, Vol. 20, p. 46, 1925; Tegland, Nautilus, Vol. 41, p. 129, 1928. Thyasira disjuncta Gabb, Tegland, Nautilus, Vol. 41, p. 129, 1928; WaterfaU, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. 282 San Diego Society of Natural History [Memoirs Type localities: Of hisecta, Miocene of Astoria, Oregon; of disjuncta, Deadman Island, San Pedro Harbor, Miocene according to Gabb, Pliocene according to Arnold, now con- sidered Pleistocene. Oligocene: Blakeley horizon, near Seattle (Arnold); Blakeley of western Washington (Weaver); Oligocene of San Emigdio region (coll. by O. P. Jenkins) ; etc. Miocene: Astoria, Oregon (Conrad); "Miocene" of Cape Yaktag, Alaska (Dall, 1900); etc. Pliocene: Wildcat beds of Scotia bluffs, Humboldt County (Stanford collection). Pleistocene: Deadman Island, San Pedro Harbor (Gabb, as disjuncta, "Miocene"); "Pliocene" of Timm's Point, near San Pedro (Arnold, 1903). Recent: Off Alaska Peninsula and southward to Oregon coast. This species is large for the genus. Specimens sometimes attain a length of 130 mm. (about 5 inches) . The anterior dorsal margin often forms a right or an acute angle at the umbo with the posterior dorsal margin. There seems to be considerable individual vari- ation in this angle. Dall and others have considered Gabb's disjuncta conspecific with Conrad's hisecta, but recently Tegland (1928) has expressed the opinion that the Miocene hisecta Conrad is different, and that the Recent and Pleistocene form should take Gabb's name. Tegland distinguishes hisecta by the pronounced anterior projection of the margin of the valves immediately below the lunule. While the amount of anterior projection varies individually, the specimens at Stanford University from the Oligocene of the Olym- pic Peninsula and from San Emigdio, from the "Miocene" near Seattle, from the Pliocene Wildcat beds of Scotia bluffs, Humboldt County, from the Pleistocene of southern California, and Recent specimens, seem to be specifically identical. We have not seen specimens which entirely coincide with the anterior profile as figured by Conrad, as all our specimens are flat below the lunule or only moderately alate. We believe that Conrad had an abnormal specimen in that regard, and under the circumstances we use the oldest name for the form which appears to persist from the Oligocene to the Recent. The Oligocene and Recent specimens are closer in appearance than is Conrad's Miocene form to either. The reader is referred to the interesting paper by Yabe and Nomura on the Japanese Recent and Tertiary species of Thyasira. Thyasira gouldii (Philippi) Ludna gouldii Philippi, Zeitschr. f. Malak., p. 74, 1845. Cryptodon gouldii Philippi, Binney, in Gould's Invert. Mass., p. 100, fig. 406, 1870. "Cryptodon flexuosus Montagu," Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 297, 1874; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 237, 1888, not of Montagu (?). Thyasira gouldi Philippi, Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 135, 136, 1903; DaU, Bull. 112, U. S. Nat. Mus., p. 33, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 120, pi. 34, fig. 5, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925; Waterfall, Univ. Calif. Publ. Geol., Vol. IS, p. 78, 1929. Pliocene: San Diego formation of the San Diego well in Balboa Park, San Diego (Dall, 1874); Pliocene of Santa Barbara (Cooper); upper Pico, Pliocene, near Ventura (Waterfall). Pleistocene: Deadman Island and Timm's Point, San Pedro region (Arnold) ; lower San Pedro fauna of Nob Hill cut, San Pedro, one valve (T. S. Oldroyd). Recent: Bering Strait to San Diego, California; also Atlantic (Dall). This species was first identified on the New England coast as flexuosa (Montagu) by Gould, Binney, and others, then separated by Philippi as a new species, Lucina gouldii. Later, Carpenter identified Montagu's flexuosa on the Pacific coast and this identifica- tion was accepted by Dall, Cooper, and others for many years. The differences are slight, and undoubtedly the EngUsh and the Pacific coast shells are closely related. Both are very small in comparison to the relatively enormous hisecta. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 283 Family CODAKIIDAE Genus CODAKIA Scopoli, 1777 Codakia J. A. Scopoli, Introd. Hist. Nat., p. 398, 1777, sole example, Chama codak Adanson, Hist. Nat. Senegal, Coq., p. 223, pi. 16, fig. 3, 1757 (original spelling codok), = ? Venus ■punctata Linnseus, fide Woodring, Carnegie Inst., Publ. No. 366, p. 107, 1925; Dall, Proc. U. S. Nat. Mus., Vol. 23, pp. 797, 798, 19:1; Trans. Wagner Inst. Sci., Vol. 3, pp. 1344, 1345, 1903. Shell rather large (often 90 to 100 mm. in height and slightly longer), discoidal, flattened, sub- circular in outline, beaks small, not very prominent; sculpture consisting of radial riblets and small growth lamellae; hinge plate strong, with deeply set ligament and the resilium posterior to the car- dinal teeth; two well-developed cardinal teeth, the right anterior distant, fittmg into a socket in the left valve; pallial line entire, often conspicuously impressed; anterior adductor scar elongate, cres- centic. Type (by monotypy), Chama codak Adanson = Venus punctata Linnseus. This genus occurs largely in tropical and subtropical waters. Codakia distinguenda (Tryon) "Lucina tigerina Linnaeus," of Carpenter, Steams, MabiUe, and of Pacific coast collectors, not Vetius tigerina Linnaeus, Syst. Nat., Ed. 10, p. 688, 1758, West Indies. Lucina {Codakia) distinguenda Tryon, Proc. Acad. Nat. Sci. Phila. for 1872, p. 130, pi. 6, fig. 3. Codakia colpoica Dall, Proc. U. S. Nat. Mus., Vol. 23, pp. 801, 821, pi. 41, fig. 4, 1901; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 463, 1926; Hanna and Hert-lein, Vol. 16, p. 140, 1927. Ludiia (Codakia) colpoica Dall, Lamy, Jour, de Conchyl., Vol. 57, p. 238, 1909. Type specimen : In the Academy of Natural Sciences of Philadelphia. Type locality: Gulf of California, collected by W. M. Gabb. Pliocene: Santa Antonita Point, Gulf of California, and of Coronados Island and Carmen Island, Mexico (Hanna and Hertlein); Coyote Mountain, Imperial County (Hanna). Pleistocene: Santa Rosalia district. Gulf side of Lower California, Mexico, one valve (coll. by Marcel Tou- waide); coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Lower California to Panama. This is the only common species of the typical subgenus in Lower California waters. Tryon named the species almost thirty years before Dall. It is probable that distinguenda is conspecific with the analagous Caribbean form, having survived without appreciable change since the Miocene on both sides of the continent. Genus LUCINA Bruguiere, 1797 Lucina J. G. Bruguiere, Encyel. M^th., Tabl. Vers, pi. 284, 1797, name and figures only, the figures later identified by Deshayes as Lucina pensylvanica, jamaicensis, and edentula (L.); Lamarck, M6m. Soc. Hist. Nat. Paris, Ser. 1, Vol. 1, p. 84, 1799, only species L. edentula; Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 165, 1817, type cited Lucina pensylvanica; Children, Quart. Jour. Sci., Lit., Arts, Vol. 14, p. 307, January, 1823, type cited Lucina jamaicensis, pi. 5, fig. 48; Dall, Proc. U. S. Nat. Mus., Vol. 23, pp. 801, 802, 1901; Trans. Wagner Inst. Sci., Vol. 3, pp. 1351, 1352, 1903; Iredale, Proc. Malac. Soc. London, Vol. 11, pt. 5, p. 302, 1915; Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 175, 1930. Phacoides Blainville, Diet. Sci. Nat., Vol. 32, p. 334, 1824, vernacular use only; Manuel de Malac, Vol. 1, p. 550 (misprinted 450), 1825, vernacular use, only species Lucina jamaicensis; Gray, Proc. Zool. Soc. London for 1847, p. 195, 1847, type, Venus jatnaiceiisis; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 805, 1901; Trans. Wagner Inst. Sci., Vol. 3, pp. 1359, 1360, 1903; Iredale, Proc. Malac. Soc. London, Vol. 11, p. 301, 1915. Type (by subsequent designation, Schumacher, 1817), Venus pensylvanica Chem- nitz, Conch. Cab., Vol. 7, p. 12, pi. 37, fig. 394, West Indies, Recent. 284 San Diego Society of Natural History [ Memoirs Shell with subcircular outline, moderately inflated, valves closed, pseudo-lunule small, some- times deeply impressed; sculpture generally concentric only, sometimes with radial ribs, a long radial sulcus or plication below the posterior dorsal margin (the escutcheon) and a shorter curved one anterior to the beaks (the Imiule) ; hmge with small cardinal teeth, often obscure in adults, laterals sometimes well developed; pallial Ime entire. As Lamarck's choice of a single species to illustrate the genus Lucina in his "Pro- drome" cannot be taken as a type designation, the first to cite a type of Lucina was Schumacher, who definitely designated and figured the Venus pensylvanica of Chemnitz. As ja7naicensis, which later became the type of Phacoides^ through Gray's designation of 1847, belongs to the same section, the latter name becomes a synonym of Lucina Bruguiere. Codakia is closely related, but has a heavier hinge plate, the anterior teeth are gener- ally closer to the cardinals, and the exteriors of the valves do not have the posterior plications that are so conspicuous on most species of Lucina. The Codakiidce are in need of a thorough revision, both nomenclatorial and morpho- logic; but lack of time and facilities makes it impracticable for the present writers to carry out now a sufficiently thorough review of the whole group to make it worth while. Because of its long standing and familiarity the genus name Lucina is used for most of the species included here in spite of the fact that typical Lucina is practically as distinct from most of the other subgenera as is Codakia, a genus with an older name. The name Phacoides applies to the same group as typical Lucina and is therefore of no value. Instead of recognizing all of the groups as subgenera of Codakia (they are all clearly rather closely related), it will probably be best eventually to treat all of the subgenera used below as distinct genera. However, until the nomenclature can be settled with reasonable certainty, it is probably better to retain the old arrangement than to introduce as full genera names that are subject to change. Loripes Poli, 1791, Oken, 1815,- is one of the old names that the writers have not been able to investigate. The shells of the Codakiidce have usually circular, saucer or cup-shaped valves, with radial or concentric sculpture, or both, two cardinal teeth in each valve, and more or less developed anterior and posterior laterals. Besides a large, rather ill-defined lunule, most of the species have a small, smooth depression immediately in front of the beaks which is often miscalled a lunule. A radial sulcus on the posterior part of the valves may be analagous to the escutcheon of other families. In typical Lucina the shell is heavy and perhaps as a consequence the lateral teeth are all well developed, and the posterior sulcus is very strong, as in Thyasira. The lunule-like depression appears to be entirely absent in Lucina, s. s., and the sculpture is concentric. Here is thick shelled also and even more convex, with strong, rounded lateral teeth and concentric sculpture as in typical Lucina; but the lunule-like depression is deeply excavated and cave-like, crowding aside the cardinal teeth. The small cardinal teeth are oblique as in typical Lucina and the true lunule is large and rather obscure; but the posterior sulcus is very much weaker than in typical Lucina. In Codakia the valves are large and of low convexity, with both con- centric and radial sculpture; the hinge is strong and concentrated, the anterior laterals are well developed, elongate, and close to the cardinals, but the posterior laterals have * As Blainville's use of Phacoides was vernacular only, the genus must date from Gray, 1847. 2 Loripes J. X. Poli. Test. Sicil.. Vol. 1. p. 31 of the introduction. 1791. Loripes Oken. Lehrbuch Nat.. Vol. 3, p. 231, 1815. f Loripes Cuvier, 1817. Dall, Proc. U. S. Nat. Mus., Vol. 23. p. 803. 1901. "Type. Amphidesma lucinalis Lamarck = Tellina lactea of Poli and others, but not of Linnseus, Lucina leucoma Turton, L. amphidesmoides and tacteoides Deshayea and L. etata Locard. Habitat, Mediterranean." Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 285 been crowded out by a very wide, shortened ligamental trough and have become obso- lete. The pseudo-lunule is small but fairly deep ; the true lunule and the escutcheon are faint. Myrtea is smaller than Codakia, with a relatively much longer and narrower ligamental trough, with small distant laterals becoming obsolete in some species, and a narrow, elongate pseudo-lunule. The sections of Myrtea, though distinguished by sculpture, appear to form a well-defined group of closely related species. Both nuttallii and teiiuisculpta have the sculptural elements of Codakia; calif arnica has closely packed concentric sculpture only ; and acutilineata has distinct concentric lamellae and smooth interspaces as in typical Lucina. Miltha has the general shape of Codakia, but the sculp- ture is practically confined to growth hues and all the laterals have become obsolete. In Anodontia the cardinals too have become obsolete, as in Thyasira, and the shell has become globose and sculptureless. Divaricella is in shape and appearance very much like some species of Myrtea, except for its divaricate sculpture; but in eburnea, at least, its laterals have become obsolete and its cardinals have been modified so that they are more Uke the cardinals of Taras. Divaricella is therefore assigned to the Ungulinidce. Both the Ungulinidce and the Thyasiridce are very closely related to the Codakiidce and might better be considered subfamilies, if indeed the Ungulinidce should be separated at all. Subgenus MYRTEA Turton, 1822 Myrtea Turton, Conchylia Insularum Britanmcarum, p. 1.33, 1822; Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 187, 1930. Myrtxa Turton, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 804, 1901; Woodring, Carnegie Inst. Wash., Publ. No. 366, p. 112, 1925. Type (by monotypy) Venus spinifera Montagu, Test. Brit., p. 577, 1803, Suppl., pi. 17, fig. 1, 1808; Recent, Great Britain. Section Myrtea, s. s. Sculpture of closely packed concentric ridges as in californica but developed into minute spines posteriorly around the escutcheon. Section Epilucina Dall, 1901 Epiludna Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 806, 1901. Type (by original designation), Lucina californica Conrad. This section is very close to Callucina Dall (same reference, — type, by original designation, Lucina radians Lamarck), which is said to have only one cardinal tooth, the other, presumably, having become obsolete. Lucina (Myrtea) californica Conrad Plate 14, Figures 15o, 156, 2Io, 2Ib Lucina californica Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 255, pi. 20, fig. 1, 1837; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 642, 1864; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 100, 1868-9; Cooper, 7th Ann. Kept. Calif. St. Mineralogist, p. 247, 1888; Keep, West Coast Shells, p. 178, fig. 151, 1888, 1892; WQliamson, Proc. U. S. Nat. Mus., Vol. 15, p. 190, 1892; Delos Arnold, Nautilus, Vol. 10, p. 142, 1897; Baker, Nautilus, Vol. 16, p. 43, 1902; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 132, 1903. Phacoides (Epilucina) calif amicus Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 813, 1901; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1381, 1903. Phacoides californica Conrad, E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2, (p. 42), 1919; Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 419, 1926. 286 San Diego Society of Natural History [Memoirs Callucina californica Dall, U. S. Nat. Mus., Bull. 112, p. 35, 1921. Phacoides californicus Conrad, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 127, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Pliocene: Cedros Island, Lower California (Jordan and Hertlein); Santa Barbara horizon, upper Pliocene, Bath-house Beach, Santa Barbara (Arnold, 1903). Pleistocene: Lower San Pedro series of Deadman Island and San Pedro; Pleistocene at Pacific Beach, San Diego (Arnold, 1903) ; lower San Pedro fauna of Nob Hill, San Pedro, plentiful (T. S. Oldroyd) ; upper San Pedro series of Deadman Island, Crawfish George's, and San Pedro, rare (Arnold, 1903) ; > upper Pleistocene of San Quintin Bay, Lower California, Mexico. Recent: Crescent City, California, to San Ignacio Lagoon, Lower California, Mexico (Dall, 1921). This species averages a little smaller and somewhat more ventricose than acutilineata. It also lacks the sharp, widely spaced concentric riblets, their place being taken by a mul- titude of low, closely spaced concentric riblets with occasional growth-line irregularities. The hinge of californica has a prominent right anterior cardinal tooth, between which and the beak the elongate, rather deep-set pseudo-lunule projects, fitting into a cor- responding space in the left valve anterior to its beak. The anterior and posterior radial plications are obscure or entirely wanting. Lucina californica Conrad ranges from the upper Pliocene to the Recent in Cali- fornia. It is much less common as a fossil than L. acutilineata Conrad. Lucina (Myrtea) lingualis Carpenter Lucina lingualis Carpenter, Annals and Magazine of Natural History, Ser. 3, Vol. 13, p. 313, April, 1S64; Brit. Assn. Adv. Sci., Kept, for 1863, p. 618, 1864. Phacoides (Cavilueina) lingualis Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 827, pi. 39, fig. 7, 1901. Phacoides lingualis Carpenter, DaU, Nautilus, Vol. 32, p. 24, 1918. Type locality: Cape San Lucas, Lower California, Mexico; Recent. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 1918). Recent: Lower California and west coast of Mexico. Lucina (Myrtea) lampros (Dall) Phacoides (Camlucina) lampros Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 827, pi. 39, fig. 9, 1901. Phacoides lampros Dall, Nautilus, Vol. 32, p. 24, 1918; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Type specimen: In the U. S. National Museum. Type locality: La Paz, Lower California, Mexico. Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Lower California, Mexico. L. lampros (Dall) seems to be allied to L. californica. Section Lucinoma Dall, 1901 Lucinoma Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 806, 1901. Type (by original designation), Lucina filosa Stimpson. Lucina (Myrtea) acutilineata Conrad Plate 14, Figures 22a, 226 Lucina acutilineata T. A. Conrad, U. S. Expl. Exped. (Wilkes), Vol. 10, Geol., p. 725, October, 1849; Newcombe, Bull. Nat. Hist. Soc. Brit. Columbia, p. 48, 1893; Delos Arnold, Nautilus, Vol. 10, p. 34, 1896, p. 142, 1897; Ralph Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 131, 1903; Dall, in Spurr, 20th Ann. Kept. U. S. Geol. Surv., Pt. 7, p. 264, 1900. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 287 Peciunculus patulus Conrad, op. cit., p. 726, pi. 18, figs. 8, 8a, 1849. Lucina annulata Reeve, Conch. Icon., Vol. 6, Lticina, sp. 17, pi. 4, fig. 17, May, 1850. ? Cyclas ■permacra Conrad, U. S. Pacific R. R. Reports, Vol. 7, p. 192, pi. 7, fig. 4, 18.57; type specimen No. 13,340, U. S. Nat. Mus. "Lucina borealis Linnaeus," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 643, 1864; Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 297, Dec, 1874; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 246, 1888, not of Linnsus. Cyclas aculilineala Conrad, Amer. Jour. Conch., Vol. 1, p. 153, 1865. Axinsta paiula Conrad, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 102, 1868-9. Phacmdes (Lucinoma) annulatus Reeve, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 813, 1901. Phacoides annulatus Reeve, Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 594, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 419, 1915; Weaver, Univ. Wash. Publ. Geol., Vol. 1, ro. 1, pp. 28, 32, 1916; Martin, Univ. CaUf. Publ. Geol., Vol. 9, p. 2.53, 1916; Nomland, Vol. 10, pp. 212, 220, 301, 303, 1917. Phacoides {Lucinmna} aculilineala (Conrad) Dall, U. S. Geol. Surv., Prof. Paper 59, p. 116, 1909. Phacoides actililineatus Conrad, Arnold, U. S. Geol. Surv., Bull. 396, p. 122, pi. 8, fig. 4, January 15, 1910; Arnold and R. Anderson, Bull. .398, pi. 30, fig. 4, 1910; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. .583, 584, 588, 590, 1913; English, Univ. Calif. Publ. Geol., Vol. 8, pp. 210, 213, 1914; Weaver, Univ. Wash. Publ. Geol., Vol. 1, ro. 1, pp. 28, 32, 1916; Van Winkle, Vol. 1, ro. 2, p. 75, 1918; DaU, .\mer. Jour. Sci., Ser. 5, Vol. 4, p. 306, 1922; Clark, Univ. Calif. Publ. Geol., Vol. 15, p. 89, 1924. Phacoides annulatus densiliralus Dall, Proc. Biol. Soc. Washington, Vol. 32, p. 249, 1919; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 126, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925. Lucinoma anmdata densilineata Dall, U. S. Nat. Mus., Bull. 112, p. 35, 1921. Phacoides {Lucinoma) annulata Reeve, DaU, U. S. Nat. Mus., Bull. 112, p. 35, 1921. Phacoides columhianum Clark and Arnold, Univ. Calif. Publ. Geol., Vol. 14, pp. 144, 145, pi. 25, figs. 2a-h, 1923. Phacoides {Lucinoma.) annulatus Reeve, Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 126, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type locality: Of L. acutilineata Conrad, Astoria, Oregon; Miocene. OUgocene: Oligocene of Chehalis Valley, Washington (Van Winkle); Sooke formation of Vancouver Island; also Seattle horizon (Oligocene ?) of Washington (Arnold and Hannibal); Oligocene of western Washington (Weaver) ; etc Miocene: Oregon; Martinez; Griswold's, San Benito County; Foxin's, Santa Barbara County (Cooper); Mio- cene of Washington and Oregon (Conrad; Dall; Weaver; etc.); Miocene of Cape Yaktag, .\Iaska (Dall, 1900); Vaqueros and Temblor (?) formations, lower and middle Miocene; San Pablo and Santa Margarita formations of middle California; base of Monterey shale in San Luis Obispo County (Nomland, 1910); Bear River Miocene (?) (Martin); Temblor of Stanford University (Arnold, 1903, as Pliocene); etc. Pliocene Etchegoin, lower Fernando, lower Sargent, Purisima, lower Merced formations of middle California (various authors); lower Fernando of Elsmere Canyon (Arnold, 1907); of Elsmere and Holser canyons (English); S. D. S. N. H. localities 201 and 206, middle (?) and lower Pico of Elsmere Canyon, respectively; localities 215 and 216, lower Pico of Fernando Pass, localities 211, 213, 214, middle Pico of Fernando Pass, Los Angeles County (H. R. G. coU.); San Diego well, middle Pliocene, San Diego (Cooper); Etchegoin of Sargent oil field, San Benito County; middle Wildcat formation of Humboldt County; Merced of Ai'o Nuevo Bay, south of San Francisco (Martin); Pico near Ven- tura (Waterfall); Santa Barbara horizon, upper Pliocene of Santa Barbara (Arnold, 1903); etc. Pleistocene: "Pliocene" and lower San Pedro series of Deadman Island and San Pedro, common (Arnold, 1903); lower San Pedro of Nob Hill, San Pedro (T. S. Oldroyd, as var. detis-ilirata Dall); Pleistocene of Pacific Beach, San Diego; rare in the upper San Pedro of Deadman Island, Crawfish George's, and San Pedro (Arnold, 1903). Recent: Alaska to Coronado Islands, Lower California, Mexico (Dall). This is a lenticular shell with rather regularly disposed, fine, sharp, concentric riblets, and without radial sculpture. The posterior radial sulcus or plication, so pronounced on L. jamaicensis, is not well developed, and the anterior one is even less well developed or entirely obsolete. The cardinal teeth are stronger and the lateral teeth much weaker than in jamaicensis. The Oligocene and Miocene specimens are so similar to those of the Pliocene and Quaternary that they are here considered conspecific. The supposed specific differences between the teeth of annulata and acutilineata is a delusion. "Phacoides" hannibali Clark is very similar and is certainly closely related. 288 San Diego Society of Natural History [ Memoirs Section Lucinisca Dall, 1901 Lvcinisca Dall, Proc. I*. S. Nat. Mus., Vol. 23, p. 805, 1901. Type (by original designation), Lucina nassula Conrad. Lucina (Myrtea) nuttallii Conrad Plate 14, Figures 4a, 4b, IS Lucina nuttallii Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 255, pi. 20, fig. 2, 1837; Carpenter, Brit. Assn. Adv. Sei., Kept, for 1863, p. 642, 1864; Gabb, Geol. Surv. Calif., Pala;o., Vol. 2, p. 100, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 247, 1888; Keep, West Coast Shells, p. 179, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 190, 1892; Delos Arnold, Nautilus, Vol. 10, p. 142, 1897; Ralph Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 132, 1903. Phacoides (Lucinisca) nuttallii Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 812, 1901; Trans. Wagner Inst. Sci., Vol. 3, p. 1373, 1903; U. S. Nat. Mus., Bull. 112, p. 35, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 126, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925. Phacoides nuttallii Conrad, var. antecedens Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, pp. 18, 19, pi. 55, &g. 6, 1907. Phacoides nuttallii Conrad, English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Nomland, Vol. 10, pp. 301, 303, 1917; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 563, 1922; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 148, 151, 152, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Hanna and Hertlein, Vol. 16, p. 142, 1927. Miocene: Santa Margarita formation, upper Miocene, north of Coalinga (Nomland). Pliocene: Lower Fernando of Elsmere and Holser Canyons, Los Angeles County (English); S. D. S. N. H. locality 207, lower Pico of Elsmere Canyon, also 216, lower Pico of Fernando Pass, and 217o, middle Pico near Holser Canyon, Los Angeles County (coll. by H. R. G.); Alcatraz asphalt mine, near Sisquoc, Santa Barbara County (Arnold, 1907); Pliocene of Pacific Beach, San Diego (Arnold, 1903) ; Pliocene of Carmen Island, Mexico (Hanna and Hertlein) ; Santa Barbara formation at Santa Barbara (Arnold). Pleistocene: Lower San Pedro series of Deadman Island and San Pedro, common; Pleistocene at Pacific Beach and foot of Twenty-sixth St., San Diego (Arnold, 1903) ; lower Quaternary at Magdalena Bay, Lower California (Jordan, 1924) ; Tomales Bay, Marin County (Dickerson) ; upper San Pedro series of San Pedro, Los Cerritos, Crawfish George's, Deadman Island, and Long Beach (Arnold, 1903); upper Pleistocene of Scammon Lagoon, San Quintin Bay, and San Ignacio Lagoon, Lower California, Mexico (Jordan, 1924, '26, '27). Recent: Santa Barbara, California, to Mazatlan, Mexico (1921). L. nuttallii Conrad is a smaller shell than californica or acutilineata and is readily recognized by the fine cancellate sculpture. Mature individuals often measure 25 mm. in altitude. Section Parvilucina Dall, 1901 Parvilvcina Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 806, 1901. Type (by original designation), Lucina tenuisculpta Carpenter. The shells of this section are smaller and more convex than those of Lucinisca. This section, like some of the others, is hardly of more than specific significance. Lucina (Myrtea) tenuisculpta Carpenter Lucina tenuisculpta Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 642, 1864; Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 297, 1874; Cooper, 7th .4nn. Rept. Calif. State Mineralogist, p. 247, 1888; Baker, Nautilus, Vol. 16, p. 43, 1902; Arnold, Mem. Caht. Acad. Sci., Vol. 3, p. 133, 1903. Phacoides (Parvilucina) tenuisculptus Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 828, pi. 40, fig. 5, 1901; U. S. Nat. Mus., Bull. 112, p. 35, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 128, pi. 15, fig. 6, pi. 33, figs, la-b, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925. Phacoides (Parvilucina) intensus Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1385, pi. 50, fig. 8, 1903. Phacoides inlensus Dall, Arnold, Smithsonian Misc. Coll., Vol. 50, p. 445, pi. 56, figs. 9a, 9/), Dec. 13, 1907; U. S. Geol. Surv., Bull. 322, pp. 59, 148, pi. 23, figs. 9o, 9b (same figures), 1907. Phacoides tenuisculpta Carpenter, Clark, Univ. Calif. Publ. Geol, Vol. 8, p. 419, 1915. Volume I ) PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 289 Shell small, ventricose, with fine radiating riblets and concentric lamellae. Height, 12 mm.; length, 13 mm. Type specimens: In the U. S. National Museum; that of intensa, No. 135,041. Type locality: Vancouver Island, British Columbia; Recent, Miocene: Lower San Pablo formation, lower part of upper Miocene of middle California (Clark). Pliocene: Middle Pliocene of San Diego well, Balboa Park, San Diego, California (Dall, 1874); Santa Maria district, Santa Barbara Co. (Arnold, 1907). Pleistocejie : Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd); Pleistocene of Spanish Bight, North Island, San Diego (Arnold, 1903; Mrs. K. Stephens, MS.); rare in the upper San Pedro series of San Pedro (Arnold). Recent: Nunivak Island, Bering Sea (Dall), to San Martin Island, Lower California (F. Baker). Codakia (Jagonia) guppyi Woodring,' from the Miocene of Jamaica, appears to be very closely related. Lucina (Myrtea) tenuisculpta Carpenter variety approximata (Dall) Plate 14, Figures 8a, 86 Phcuxddes (Parvilucina) approximalus Dall, Proc. U. S. Nat. Mus., Vol. 2.3, p. 813, pi. 39, fig. 4, 1901; U. S. Nat. Mas., Bull. 112, p. 35, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 128, 1924; T. S. Oldroyd, Proc. II. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925. Parvilucina approximalus Dall, Nautilus, Vol. 32, p. 24, 1918. Pbacoides approximalus Dall, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, no. 7, p. 244, 1926. Type specimen: In the U. S. National Museum. Pleistocene: Lower San Pedro fauna of Nob HiU cut, San Pedro, "about 100 valves" (T. S. Oldroyd); lower Quaternary at Magdalena Bay, Lower California, Me.xico (Jordan; Dall, as warm-water Pleisto- cene); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Monterey, California, to Panama (Dall, 1921). This small, appropriately named form is very close to L. tenuisculpta Carpenter, but, according to Dall, is "smaller, more dehcate, without the anterior right cardinal tooth which is developed in the northern shell." The radial sculpture of variety approximata is more definitely developed than that on typical tenuisculpta, it being very faint or obso- lete on the latter form. It seems nearer the truth to consider approximata a variety or synonym of Carpenter's species. Lucina (Myrtea) mazatlanica Carpenter Lucina mazatlanica Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., pp. 99, 100, 1857; Brit. Assn. Adv. Sci., Rept. for 1856, pp. 248, 307, 1857. Phacoides {Here) mazatlanicus Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 811, 1901. Phacoides mazatlanicus Carpenter, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924. Type locality: Mazatlan, Mexico; Recent. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (E. K. Jordan). Recent: Gulf of California, Mexico, to Panama. We have not seen specimens of this species. Dall remarks: "Carpenter's specimens are so small that it is difficult to be certain about them, but they appear to be a distinct species, allied to the Atlantic P. sombrerensis. They are distinguished from young approximalus by their dense concentric lamellation." « Carnegie InBt. Wash., Publ. No. 366, p. 110. pi. 14, figs. 5, 6. 7, 1925. 290 San Diego Society or Natural History [Memoirs Subgenus BELLUCINA DaU, 1901 Bellucina Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 806, 1901. Type (by original designation), Lucina pisum Reeve, 1850 (not Sowerby, 1837, nor d'Orbigny, 1841, nor Philippi, 1850), = Lucina eucosmia (Dall), 1901, figured by Reeve, Conch. Icon., Vol. 6, Lucina, sp. 66, pi. 11, figs. 66a-b, 1850. "Dorsal areas and sculpture strong." (Dall.) Dall's arrangement of the Codakiidce appears somewhat mechanical and not entirely satisfactory. Bellucina was proposed as a section of the subgenus Parrilucina; but as Parvilucina, of which L. tenuisculpta is the type, is closer to Myrtea than is Bellucina, Parvilucina is treated as a section of Myrtea and Bellucina is used as a subgenus. Lucina (Bellucina) cancellaris Philippi Lucina cancellaris R. A. Philippi, Zeitsehr. f. Malakozool., p. 21, Feb., 1846. Phacoides (Bellucina) cancellaris Philippi, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 814, pi. 39, fig. 11, 1901. Phacoides cancellaris Philippi, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Cedros Island, west of Lower California, south to the Gulf of California and to Panama, in 5 to 30 fathoms (Dall, 1901). As figured by Dall, this species has about eleven broad ribs with concentric cancella- tions. Subgenus HERE Gabb, 1866 Here Gabb, Geological Survey of California, Palaeontology, Vol. 2, sect. 1, part 1, p. 28, 1866; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 251, 1871, "Type, Luc. (Here) Richthofeni, Gabb"; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 805, 1901. Type (virtually by monotypy; designated by Stoliczka, 1871), Lucina (Here) richt- hofeni Gabb. "Shell having all of the usual characters of Lucina, except that the lunule is very deeply excavated, penetrating the hinge plate, and almost perforating it; bounded anteriorly by the anterior lateral tooth, and posteriorly by the cardinal tooth." (Gabb.) Lucina (Here) excavata Carpenter Plate 14, Figures 2, 5, 10 Lucina excavata Carpenter, Cat. Reigan Coll. Mazatlan Moll. Brit. Mus., p. 98, 1857. Lucina (Here) richthofeni Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 29, 1866. Phacoides (Here) richthofeni Gabb, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 810, pi. 40, figs. 7, 9, 1901; U. S. Nat. Mus., Bull. 112, p. 35, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 126, 1924. Phacmdes richthofeni Gabb, Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 543, pi. 45, fig. 4, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Clark, Vol. 8, p. 419, 1915; Nomland, Vol. 10, pp. 220, 310, 1917; Wagner and SchilUng, Vol. 14, pp. 243, 244, 1923; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Proc. CaUf. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Lucina (Here) excavata Carpenter, Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 181, pi. 15, fig. 3, pi. 17, fig. 5, 1930. Type localities: Of richthofeni, San Fernando Valley, Los Angeles County, Pliocene; of excavata, Mazatlan, Mexico, Recent. Oligocene: San Emigdio region (Wagner and Schilling). Miocene: Lower Miocene three miles south of Calabasas, Los Angeles County (.\rnold, 1907); Santa Mar- garita formation, upper Miocene, of the Tejon Hills (Nomland); San Pablo formation of middle California (Clark). Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 291 Pliocene: Lower Fernando of Elsmere and Holser canyons, Los Angeles County (English) ; common at various lower and middle Pico localities in Elsmere Canyon and the San Fernando Pass region, Los Angeles County (coll. by H. R. G.); Pliocene of San Fernando Valley (Gabb); rare in the Chione elsmerensis zone of the Etchegoin formation (Nomland). Pleistocene: Lower Quaternary at Magdalena Bay, and upper Pleistocene at San Quintin Bay, Lower Cali- fornia, Mexico (E. K. Jordan). Recent: San Pedro, California, to Mazatlan, Mexico. Lucina excavata Carpenter is readily recognized by its globose, inflated shape, con- centric ridges, and deeply depressed pseudo-lunule. With the two valves together, as they often are, even in fossils, it resembles a nut. Subgenus MILTHA H. and A. Adams, 1857 Miltlia H. and A. Adams, Genera of Recent Mollusca, Vol. 2, p. 468, April, 1857, only species, Lucina (Miltha) childreni Gray; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 806, 1901; Trans. Wagner Free Inst. Sci., Vol. 3, p. 1361, 1903. Milthea H. and A. Adams, Meek, Report of the U. S.. Geological Survey of the Territories, Vol. 9, p. 131, 1876. Type (by monotypy), Lucina (Miltha) childrence Gray, 1825, Recent, from Brazil (see below). "Shell inequivalve, with the surface of the valves nearly smooth. Hinge with the lateral teeth obsolete." (H. and A. Adams.) The type of this subgenus was long supposed to have come from the Pacific coast,' but Dall has stated that its habitat is Brazil. Lucina (Miltha) xantusi (DaU) Plate 14, Figures 20a, 20b "Lucina childreni Gray," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 552, 620, 1864, (? not Lucina childrense J. E. Gray, Annals of Philosophy, Vol. 25, p. 136, February, 1825; nor Lucina "childreni" Gray, G. B. Sowerby, 2nd, Genera of Shells, Pt. 27, 1827, nor "Tellina" childreni Gray, Wood, Index Testaceologicus, Supplement, Plate I, fig. I, 1828); also of Pacific coast conchologists prior to 1905. "Phacoides (Miltha) childreni Gray," Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 812, I90I; Trans. Wagner Inst. Sci., Vol. 3, p. 1377, 1903. Phacoides (Miltha) xantusi DaU, Nautilus, Vol. 18, p. Ill, Feb., 1905; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, pp. 474, 475, pi. 28, fig. 7, pi. 29, fig. 1, 1926. ? Phacoides joannis Dall, NautLus, Vol. 18, p. 112, 1905 (original description ?). Phacoides (Miltha) sanctaecrucis Arnold, U. S. Geol. Surv., Bull. 396, pp. 17, 57, pi. 6, fig. 6, January 15, 1910; Arnold and R. Anderson, Bull. 398, pi. 28, fig. 6, 1910. Phacoides "santxcrucis" Arnold, English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914. Phacoides "santsecrusis" Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 301, 1917. Type localities: Of L. childrence Gray, Brazil (?) ; of P. xantusi Dall, Lower California; of P. sanctcecrucis Arnold, in "reef bed" one-fourth of a mile southeast of Barton's Cabin, Devil's Den district, Kern County, Temblor formation, middle Miocene, Turritella ocoyana zone (lower Miocene of Arnold, 1910). Miocene: Temblor formation of Devil's Den district, Kern County; Miocene of Mindego Creek, Santa Cruz Mountains, San Mateo County; in many of the "lower" [middle ?] Miocene faunas of the Coast Ranges (Arnold, 1910); Santa Margarita formation, upper Miocene, of the Tejon Hill.s and also north of Coalinga (Nomland) . Pliocene: Lower Fernando of Elsmere and Holser Canyons, Los Angeles County (English); S. D. S. N. H. localities 201, 203, 207, and 210, lower Pico of Elsmere Canyon, Los Angeles County (coll. by H. R. G.); Etchegoin of Coalinga region (Nomland); S. D. S. N. H. localities 211, 213, and 214, middle Pico west of Fernando Pass, and locality 217, middle Pico near Holser Canyon, Los .Angeles County (coll. by H. R. G.); Pliocene of San Juan, Gulf of California (Dall, 1903); Pliocene of Coyote Mountain, western Imperial County, California (Hanna). Recent: Gulf of California, Cape San Lucas, Lower California; Mazatlan, Mexico (Dall, 1901). 1 Carpenter, Brit, Ass. Adv. Sci., Rept. for 1863, p. 522, 1864, says of this species: "There is no authority for the statement that it comes from Brazil. The Br. Mus. specimens are from 'Mus. Cracherode', and are probably west coast. The only known locality is Cape St. Lucas." 292 San Diego Society of Natural History [Memoirs This is a moderately large, flattened species, showing the growth lines clearly. Some specimens show an inward bending of the growth lines occurring in a radial band from the umbonal region to the ventral margin of the valve, but this character seems to occur sporadically and cannot be used for specific or varietal differentiation. Lucina (Miltha?) jacalitosana (Arnold) Paphia jacalitosana Arnold, U. S. Geol. Surv., Bull. 390, p. 66, pi. 16, fig. 3, January 15, 1910; Arnold and R. Anderson, Bull. 398, pi. 38, fig. 3, 1910. Type specimen: U. S. National Museum, Cat. No. 165,587. Type locality: On Ramirez place at forks of Jacalitos Creek a short distance north- east of Reef Ridge, Coalinga district, California; Jacalitos formation, lower Pliocene. Pliocene: Lower Pliocene at type locality. So far as the writers know, this species has not been recognized by paleontologists since its original description. It may be a synonym of Lucina (Miltha) xantusi (Dall). Genus ANODONTIA Link, 1807 Anodontia T.ink, Beschr. Rostock Samml., p. 56, 1807, sole example, Venus edentula Gmelin, fide Dall, Trans. Wagner Inst. Sci., Vol. 7, p. 1352, 1903. Lucina (Bruguiere) Lamarck, of Dall, Proc. U. S. Nat. Mus., Vol. 23, pp. 801, 802, 1901. Pegophysema Stewart, Special Publ. No. 3, Acad. Nat. Sci. PhUa., p. 185, 1930. Type (by subsequent designation, Dall, 1901), Venus edentula Linnaeus. "Shell inflated, thin, concentrically striated, anterior and posterior dorsal areas obsolete; lunule deep and narrow, no visible escutcheon; ligament and resilium deeply inset, but not occluded; margins entire, anterior adductor scar long, hinge wholly edentulous, shell usually large." (Dall.) This genus is related to Lucina as Serripes is to Lcevicardium. Anodontia edentuloides (Verrill) Loripes edenluloides Verrill, Amer. Jour. Sci., Ser. 2, Vol. 49 (Whole No. 99), p. 226, 1870. Lucina edenluloides Verrill, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 802, 1901; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 466, 1926. Type specimen: In the Museum of Yale University. Type locality: La Paz, Lower CaUfornia, Mexico; Recent. Pliocene: Imperial formation, Coyote Mountain, western Imperial County (Hanna). Recent: Magdalena Bay, Lower California, south and into the Gulf of California (Dall). This species is closely allied to the Caribbean shell which Reeve identified as L. edentula (not the edentula of Linnaeus, fide Dall, 1901). It was described by Verrill as being "subglobose, and much more swollen than L. edentula. The apex is more prominent and curved, and the lunular region more deeply excavated. The ligament is shorter and its supporting plate is not so stout, and its inner edge but little elevated above the liga- ment groove." Family UNGULINIDAE Shell subcircular in outline, or irregular if nestling in habit; cardinal teeth small, normal ; laterals obscure or absent; valve margins plain; pallial line entire. It is probable that this family should be included in the Codakiidce. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 293 Genus TARAS Risso, 1826 Taras Risso, Hist. Nat. Eur. M^rid., Vol. 4, p. 344, 1826; Stewart, Special Publ. No. 3, .\cad. Nat. Sci. Phila., p. 193, 1930. Mysia Leach, Brown, 111. Conch. Gt. Brit., Ed. I, pi. 16, fig. 11, 1827; Ed. 2, p. 98, 1844; Gray, Syn. Cont. Brit. Mus., Ed. 42, p. 150, 1840; Ann. Mag. Nat. Hist., Vol. 20, p. 272, 1847; Cossmann, Soc. Roy. Malac. Belgique, Vol. 22, p. 17, 1887; not Mysia Leach in Lamarck, Hist. Nat. Anim. s. Vert., Vol. 5, p. 543, 1818; Desh. and M. Edw. Ed., Vol. 6, p. 229, 1835; Gray, Proc. Zool. Soc. London, p. 195, 1847; type (by monotypy) Venus undata Pennant, referred by Dall to the Veneridse. Diplodonta H. G. Bronn, Ergebnisse meiner naturhistorisch-okonomischen Reisen,Vol. 2, p. 484, 1831; Italiens Tertiar- GebUde und deren organische Einschlusse, pp. ix-xii, 1831; Herrmannsen, Indicis Generum Malacozoorum, Primordia, Vol. 1, p. 392, 1847, type designated, Venus lupinus Brocchi, Conch. Subappen., Vol. 2, p. 553, pi. 14, fig. 8, 1814, = ? Tellina rolundala Montagu, Pliocene of England and Italy, Recent; Dall, Jour. Conch., Vol. 9, no. 8, p. 244, Oct., 1899; Proc. U. S. Nat. Mus., Vol. 23, p. 791, 1901; Dall, in Zittel-Eastman, Text- book of Paleo., Ed. 2, Revised, p. 487, 1913; Woodring, Carnegie Inst. Wash., Publ. No. 366, p. 128, 1925. Type (by monotypy), Taras antiqiiatus Risso, op. cit., p. 344, fig. 167, 1826, Pliocene or Pleistocene of Trinite (Riviera), related to rotundatus (Montagu), ^dc Stewart. Thin-shelled, orbicular, convex, concentrically striate or pustulose ; cardinals 2 :2, the left anterior and right posterior bifid; laterals obscure or absent. (Dall, m Zittel-Eastman, 1913.) Geologic range: Eocene to Recent. Section Taras, s. s. Shell with growth lines only, rather ventricose, valves slightly inequilateral. Taras orbellus (Gould) Plate 14, Figures 14a, 14b Lucina orbella Gould, Proc. Boston. Soc. Nat. Hist., Vol. 4, p. 90, 1852; Boston Jour. Nat. Hist., Vol. 6, pp. 395, 396, pi. 15, fig. 3, 1853. Diplodonta orbella Gould, Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 238, 1888; Dall, Jour. Conchology, Vol. 9, no. 8, p. 245, 1899; Trans. Wagner Inst. Sci., Vol. 3, p. 1189, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 795, 1901; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 134, pi. 18, figs. 8, 8a, 1903; Lamy, Jour, de Conchyl., Vol. 57, p. 238, 1909; Clark, Univ. Calif. Publ. Geol., Vol. S, p. 418, 1915; DaU, Nautilus, Vol. .32, p. 24, 1918; U. S. Nat. Mus., Bull. 112, p. 34, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 124, pi. 6, figs. 5, 6, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925. Type locality: San Diego, California; Recent. Miocene: Upper San Pablo of middle California (Clark, 1915). Pliocene: Etchegoin of middle California (Clark, 1915; etc.); San Diego well, Balboa Park, San Diego (Dall). Pleistocene: Lower San Pedro series of Deadman Island, San Pedro Harbor, rare (.Arnold, 1903); lower San Pedro series of Nob Hill cut (T. S. Oldroyd); lower Quaternary at Magdalena Bay, Lower Cali- fornia, Mex-ico (E. K. Jordan); foot of Twenty-sixth St., San Diego; upper San Pedro series at San Pedro and Crawfish George's (.Arnold); warm-water Pleistocene fauna at Magdalena Bay, Lower California, Mexico (Dall, 1918); upper San Pedro formation at Santa Monica (Oldroyd Collection). Recent: PribUof Islands, Bering Sea, to Gulf of California (DaU). This is a rather small, subglobose shell with median, inconspicuous beaks and fine growth lines. T. harfordi (F. M. Anderson) and T. buwaldanus (Anderson and Martin) are very similar. Taras harfordi (F. M. Anderson) Diplodonta harfordi Anderson, Proc. Calif. Acad. Sci., Ser. 3 (Geol.), Vol. 2, p. 197, pi. 17, figs. 88, 89, 1905; Arnold, U. S. Geol. Surv., Bull. 396, pp. 25, 140, pi. 17, fig. 6, Jan. 15, 1910; .Arnold and R. .Anderson, Bull. 398, pi. 39, fig. 6, 1910; Woodford, Univ. Calif. Publ. Geol., Vol. 15, p. 208, 1925. 294 San Diego Society of Natural History [ Memoirs Miocene: Temblor formation, lower middle Miocene, sea cliff one- quarter mile northwest of Lagmia Canyon, Orange County, California (Woodford); Santa Margarita formation west of Coalinga (Coalinga Beds, type locality, F. M. Anderson). Pliocene: Questionably in the Jacalitos beds, lower part of the Etchegoin formation, lower Pliocene (Arnold, 1910); Etchegoin of Coalinga region (Arnold and F. M. Anderson). This species appears to be very closely related to orbellus, but can be distinguished by its more projecting, less twisted beaks, and by the fact that orbellus is usually more inflated, especially in the northern variety aleuticus (Dall). Arnold's figured specimen looks more like parilis or sericatus. Taras buwaldanus (Anderson and Martin) Diplodonta huwaldana Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 56, pi. 3, figs, la, lb, 1914. Type locality: Middle portion of the lower Miocene, near Barker's Ranch, Kern River. This form is small, round, smooth, inflated, practically indistinguishable from orbellus, but the dorsal margin is more convex behind the beaks. T. harfordi is less convex and has more prominent, straighter beaks, showing a slightly closer relationship with parilis ( + sericatus) . Section Felaniella Dall, 1899 Felaniella Dall, Journ. Conch., Vol. 9, no. 8, p. 244, October, 1899. Type (by original designation), Felania usta Gould. "Shell like Diplodonta, but heavy, compressed, externally smooth, with a conspicuous dark periostracum and less equilateral valves." (Dall.) This section is probably of little value. Dall has placed the species with the punctate or pustulate surface (type D. semirugosa Dall, + D. semiaspera Carpenter, Mazat. Cat., p. 102, 1857, not of Philippi, 1836) in the section Phlyctiderma Dall, op. cit., p. 246. Taras parilis (Conrad) Loripes parilis Conrad, Amer. Jour. Sci., Ser. 2, Vol. 5, p. 432, fig. 7, 1848. Mysia parilis Conrad, Amer. Jour. Conch., Vol. 1, p. 153, 1865; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 100, 1868-9. Diplodonta parilis Conrad, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1182, 1900; Arnold, U. S. Geol. Surv., Bull. 396, p. 140, pi. 17, fig. 5, 1910; Arnold and R. Anderson, BuU. 398, p. 108, pi. 39, fig. 5, 1910; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 588, 1913; Clark, Univ. Calif. Publ. Geol., Vol. S, p. 418, 1915; Nomland, Vol. 10, p. 219, 1917. Miocene: Empire formation of Oregon (Dall; Arnold and Hannibal; Howe; etc.); Montesano formation (Weaver); San Pablo formation (Clark). Pliocene: Etchegoin formation (Arnold); Chione elsmerensis zone and Pecteii coaKngensis zone of Etchegoin formation of Coalinga region (Nomland) Pleistocene and Recent: As T. sericatus (Reeve). This species resembles the form sericatus (Reeve) so closely that the latter should be considered conspecific. Volume I J PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 295 Taras parilis (Conrad) variety sericatus (Reeve) Plate 14, Figures 12a, 12b Lucina sericata Reeve, Conch. Icon., Vol. 6, Lncina, sp. 55, pi. 9, fig. 55, June, 1850. Diplodonta serricata Reeve, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 248, 1857; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 134, pi. 18, figs. 5, 5a, 1903. Felaniella seHcata Reeve, Dall, U. S. Nat. Mus., Bull. 112, p. 34, 1921. Diflodonla sericata Reeve, I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 1, p. 125, 1924. Pleistocene: Foot of Twenty-sixth Street, San Diego, common (Arnold; Mrs. K. Stephens MS.); upper San Pedro series of San Pedro (Arnold). Recent: San Diego, California, to Panama. This form is probably inseparable from the Pliocene form of Taras parilis (Con- rad), but we retain it as a variety until larger suites of specimens are available for study. Lucina cornea Reeve and Lucina nitens Reeve (op. cit. species 25, 50) are probably of the same species. Genus DIVARICELLA von Martens, 1880 Lucina sp. of many authors before 1880. "Cyclas Klein," Morch, Cat. Yoldi, Pt. 2, p. 32, C. guadrisulcata d'Orbigny + T. dimricnta Chemnitz included, 1853; not Cyclas Lamarck, Eney. M^th., Tabl. Vers, pi. 301, 1798; M(?m. Soc. Hist. Xat. Paris, Ser. 1, Vol. 1, p. 84, 1799. Divaricella von Martens, in Moebius' Beitrage zur Meeresfauna der Insel Mauritius und der Seychellen, MoUusken, p. 321, 1880, only species L. angulifera von Martens, pi. 22, fig. 14, = Lucina ornata Reeve, 1850, not of C. B. Adams, 1852, ^e Dall, 1903; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1387, 1903. Lucinella Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 18, 1884. Type (by monotypy), Lucina angulifera von Martens, op. cit., pi. 22, fig. 14, 1880, = Lucina ornata Reeve, Conch. Icon., Vol. 6, Lucina, pi. 8, fig. 48, 1850; Mauritius, Recent. Shell much like that of Taras, but with divaricate sculpture, a more polished .surface, and lower convexity. Geologic range: Eocene to Recent. The differences between Myrtea and Divaricella might not be of more than sub- generic importance, for species of the latter group closely approach species of Myrtea, except in sculpture. Divaricella generally does not have external anterior and posterior ridges, the pseudo-lunule is very small and deeply impressed, larger in the right valve than in the left, and the lateral teeth are small. However, Divaricella seems to be even more like Taras. The divaricate sculpture is so conspicuous that the custom has been to consider it a distinctive generic character. Lucinella Monterosato differs from Divaricella, s. s., according to Dall, in that the ligament is obsolete, and the resilium is wholly internal, as in Semele. It was considered a synonym of Divaricella by Bucquoy, Dautzenberg, and Dollfus. Divaricella dentata (Wood) Tellina dentata Wood, General Conch., p. 195, pi. 46, fig. 7, 1815; Dillwyn, Descr. Cat. Rec. Sh., Vol. 1, p. 103, 1817; Tryon, Proc. Acad. Nat. Sci. Phila. for 1872, p. 85, 1872; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1390, 1903; not Lucina dentata Defrance, Diet. Sci. Nat., Vol. 27, p. 275, 1823; nor L. dentata Basterot, Mem. Soc. Hist. Nat. Paris, Vol. 2, p. 87, 1827. Lucina divaricata Linnaeus," Lamarck, 1818, and others, not Tellina divaricata Linnaeus. Lucina serrata d'Orbigny, Voy. Amer. M(^rid., Vol. 5, Pt. 3, p. 384, 1840; in R. de la Sagra, Hist. Phys. Polit. Nat. Cuba, Vol. 2, p. 295, pi. 27, figs. 37, 39, 1853. ? Lucina ornatissima d'Orbigny, op. cit., p. 384, 1840, fide Tryon. ? Lucina chemnitzii Philippi, Zeitschr. f . Malakozool., Vol. 4, p. 151, March ?, 1849. ? Lucina ornata Reeve, Conch. Icon., Vol. 6, Lucina, pi. 8, fig. 48, 1850. 296 San Diego Society of Natural History [ Memoirs Shell of medium size, suborbicular; margin of valves circular in outline except for the dorsal portion, which is less curved, margin somewhat serrated, especially on the dorsal portions of old individuals; umbones central, rather small, beaks shghtly inclined forward; surface of valves with divaricate sculpture; hinge teeth small, posterior lateral elongate, distant, anterior cardmal distant, assuming position of a lateral. Dimensions of mature specimens: Length 20 to 28 mm. ; height, 19 to 26 mm.; convexity of both (matched) valves, 12 to 15 mm. Variety dentata, s. s. Hinge teeth very weak, posterior lateral absent or reduced to a slight, distant protrusion, ex- tending downward, not outward. Pleistocene: Santo Domingo (Gabb, fide Dall). Recent: Cape Hatteras, North Carolina, to Brazil (Dall). Divaricella dentata (Wood) has a very much involved early synonymy. Unfortu- nately, Wood did not assign any habitat to his well-figured species, but the American Atlantic coast shell is so similar to Wood's picture that it is probable that later authors have correctly identified it. In his Catalogue of the Lucinidce Tryon' included a number of names, most of which are probably closely related to dentata, if not exact synonyms; but a few, such as L. eburnea Reeve and L. quadrisidcata d'Orbigny,^ appear to be vari- etally or specifically distinct. D. quadrisulcata (d'Orbigny), according to Dall, can be distinguished by its "extremely small, deep, cordate lunule" and "frequently by its greater -size and solidity." Its range is given as Miocene to Recent. D. ehurnea (Reeve) was described from Recent specimens from Mazatlan. It appears to be only varietally distinct from the Florida dentata. Divaricella dentata (Wood) variety eburnea (Reeve) Plate 14, Figures la, 16 Lucina cbvrnea Reeve, Conch. Icon., Vol. 6, pi. 8, fig. 49, June, 1850; not Lvcina eburnea Deshayes, Bull. Soc. G^ol. France, Vol. 6, p. 321, 18.3.5, nnmen nudum. Divaricella eburnea Reeve, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 815, 1901; Nautilus, Vol. 23, p. 24, 1918; Hanna, Proc. Calif. .A.cad. Sci., Ser. 4, Vol. 14, p. 464, pi. 26, figs. 8, 9, 1926; Hanna and Hertlein, Vol. 16, p. 140, 1927. Divaricata eburnea Reeve, Kew, Univ. Calif. PubV. Geol., Vol. 8, p. 46, 1914. Divaricella lucasa7ia Dall and Ochsner, Proc. Calif. Acad. Sci., Ser. 4, Vol. 17, p. 122, pi. 2, figs. 17, 21, 24, 1930, new name for eburnea Reeve. Shell like that of the typical variety of dentata, but with the hinge teeth stronger, the posterior lateral tooth projecting outward from the hinge. Type locality: Mazatlan, Mexico; Recent. Pliocene: Coyote Mountain, lower division (Kew) ; Imperial formation of Coyote Mountain (Hanna) ; Carmen Island, Gulf of California, Me.xico (Hanna and Hertlein). Pleistocene: Magdalena Bay, Lower California, INIexico (DaU); Oa.xaca, Mexico (coll. by R. H. Palmer); Albemarle Island, Galapagos Group (Dall and Ochsner). Recent: Cape St. Lucas, Lower California, Mexico, to Panama (Dall, 1901); ? Caribbean. The comparison of a series of specimens of dentata from Florida localities with numerous specimens from west Mexican waters shows that the only significant difference between the two forms is in the hinge teeth. The Atlantic form, which we have assumed to be the typical variety, has either a very small posterior lateral tooth projecting down- ward toward the ventral margin, or none at all. This difference between the two varieties is small but in all the specimens examined it is constant. 1 Catalogue and Synonymy of the Recent Species of the Family Litcinids, Proc. Acad. Nat. Sci. Phila. for 1872, pp. 82-96; see page 85. ' Voy. Amer. M^rid., Vol. S. Ft. 3, p. 584. 1846: in R. de la Sagra, Hist. Phys. Polit. Nat. Cuba, Moll., Vol. 2, p. 294, pi. 27, figs. 34, 36. 1853; also figured by Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1389, pi. 51. fig. 1. 1903. For dates of publication of the natural history parts of d'Orbigny's Voy. Amer. M^rid.. see Sherborn and Woodward. Ann. Mag. Nat. Hist., Ser. 7. Vol. 7, pp. 38S-390. 1901. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 297 It should be noted that the strength of the serrations on the margins of the valves of dentata, both on the typical dentata and on the variety ehurnea, is a function of the age of the individual. Large shells, representing mature individuals, are conspicuously ser- rate, especially on the dorsal margins, whereas small, young shells may have almost smooth margins. The serrations tend to be most prominent on the posterior dorsal mar- gins. Since Deshayes' use of the name eburnea in 1835 is merely as a nornen nudum in a list, it does not invalidate Reeve's name; and unless some other use before 1850 is found, lucasana is unnecessary. The name quadrisulcata noted above in the discussion of the genus may be an early, valid name for eburnea, in which case the latter will be discarded anyway. E. A. Smith' stated that he was not able to find any valid distinction between specimens of eburnea (Reeve) from St. Elena, West Colombia, and Panama and quad- risulcata (d'Orbigny). It would not be surprising to have this variety in the Caribbean also. Divaricella dentata (Wood) varietj' perparvula Dall Lnccina pisum Philippi, Abbild. Besch. Conch., Vol. 3, p. 105, pi. 2, fig. 9, April, 1850; not L. pisum Sowerby, 1837, nor L. pisum d'Orbigny, 1841, ^"de Dall, nor L. pisum Reeve, November, 1850. Divancella perparvula Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 815, pi. 39, fig. 8, August 22, 1901; Bull. 112, U. S. Nat. Mus., p. 36, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924. Shell small, globular, with rather sparse sculpture, more tumid than the young of eburnea. Length and height each about 7 mm. (After Dall.) Type specimen: Of perparvula Dall, in U. S. National Musetim. Type locality: Of L. pisum Philippi, Mazaltaa, Mexico; Recent. Pleistocene: Magdalena Bay, Lower California, Mexico (Jordan). Recent: Cape San Lucas to Ecuador (Dall, 1921). The size of this shell suggests that it might be the young of dentata variety eburnea (or quadrisulcata), but the figures given by Philippi and by Dall show less flattening of the profile of the dorsal margin. Authentic specimens have not been available. Tenta- tively, we have considered it a small variety of dentata. The sparseness of the divaricating grooves is due, at least partly, to the magnification of the illustrations of this variety. Superfamily Sphaeriacea Shells specialized for fresh or brackish water conditions. Family SPHAERIIDAE Hinge with cardinal teeth variable, sometimes promiaent and bifid at the summit, three in each valve, or hmge plate not definitely thickened, cardinals widely divergent or thin and nearly parallel to hinge margui; lateral teeth separated from the cardinals, anterior and posterior double in the right valve, single in the left. Geologic range: Triassic to Recent. The shells of this family are variable in shape and in the character of the hinge. It might have seemed desirable to separate the species having definite diverging cardinal teeth from those which have an unthickened hinge plate and cardinal teeth which are obscure or very thin and parallel to the hinge margin, but the type of Sphcerium Scopoli, as figured by Forbes and Hanley, scarcely permits placing Sphcvrium and Corbicula in different Families. ' Challenger Repts., Zool., Vol. 13, Pt. 1, p. 178, 188S. 298 San Diego Society of Natural History [ Memoirs Genus CORBICULA Megerle von Miihlfeld, 1811 Corhicula J. K. Megerle von Miihlfeld, GeseUschaft Naturforschender Freunde zu Berlin, Magazin, Jahrgang 5, pt. 1, p. 56, 1811, includes Corbicula fliiminalis; Gray, Proc. Zool. See. London, Pt. 15, p. 184, 1847. Cyrena Lamarck, Hist. Nat. Anim. s. Vert., Vol. 5, p. 551, 1818; includes C. ccrr Lamarck and others; Children, Quart. Jour. Sci., Lit., Arts, Vol. 14, p. 311, January, 1823, type cited, "Cyrena cor Lamarck," figured pi. 6, fig. 53. Tyiie (by subsequent designation. Gray, 1847), Corbicula fluminalis Megerle, = Tellina fluminalis Miiller, Verniium Terrest., Vol. 2, p. 205, 1774 + Cyrena cor Lamarck. Shell rounded-trigonal, ventricose, concentrically sculptured, with smooth margins; cardinals three, laterals smooth or cross-striated. Geologic range: Cretaceous to Recent. Corbicula gabbiana (Henderson) Cyrena California Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 26, pi. 7, fig. 45, 1866, p. 98, 1868-9; Cooper, 7th Ann. Report Calif. State Mineralogist, p. 238, 1888; not Cyrena californica Prime, 1865. Corbicula californica Gabb, Clark, Univ. Calif. Publ. Geol., Vol. 7, p. 57, 1912. Cyrena (Corbicnla) californica Gabb, Clark, Univ. Calif. Publ. Geol., Vol. 8, pp. 418, 459, pi. 56, fig. 2, 1915. Corbicula gabbiana Junius Henderson, Nautilus, Vol. 33, p. 120, April 1920, new name for C. californica Gabb, 1866, not Cyrena californica Prime, 1865. Type locality: Kirker's Pass, Contra Costa County, California, upper Miocene (Gabb, as "Pliocene"). Miocene: L'pper part of San Pablo formation, upper Miocene, at Kirker's, and along San Pablo Bay, Contra Costa County (Clark, 1915). Pliocene: Jacalitos formation, lower Pliocene (Clark). This species is quite variable in shape. Generally the umbones are quite prominent. We have not seen the hinge. Corbicula kettlemanensis (Arnold) Sphserivm l-ellhmanensis Arnold, U. S. Geo!. Sur^'., Bull. 396, p. 94, pi. 30, figs. 1, la, January 15, 1910; Arnold and Anderson, Bull. 398, pi. 52, figs. 1, la, 1910; Hannibal, Proc. Malac. Soc. London, Vol. 10, p. 131, 1912. Type specimen: U. S. National Museum, No. 165,519. Type locality: Near Kettleman Hills, Coalinga district, California; Pleistocene. Pleistocene: Base of the Tulare formation, near Kettleman HiUs, Coalinga district, California, fresh water, lower Pleistocene (Arnold, as "Pliocene"). Arnold's figure of this species shows it to have cardinal teeth more like Corbicula than Sphcerium. Hannibal synonymized this species along with S. cooperi Arnold under "Spharium (Amesoda) simile Say." S. cooperi Arnold is quite different. Genus SPHAERIUM Scopoli, 1777 Sphsrium Scopoli; Introductio ad Historiam Naturalem, pp. 397, 398, 1777, only species Tellina cornea; placed on the ofiBcial list of Generic Names by Opinion 94 of the Int. Comm. Zool. Nomen., Smiths. Misc. coll.. Vol. 73, p. 13, 1926. Cyclas Lamarck, Ency. M6th., pis. 301, 302, 1798, fide Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 196, 1930. Type (by monotypy), "Tellina cornea" Linnaeus, Syst. Nat., Ed. 10, p. 678, 1758; figured by Forbes and Hanley, Hist. Brit. Moll., Vol. 2, p. 113, pi. 37, figs. 3-6, 1853. Shell with a scarcely thickened hinge plate ; weak cardinal teeth, widely diverging and in extreme cases very thin and parallel to the hinge margin. Distribution: In fresh and brackish water. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 299 Sphaerium cooperi Arnold Sphserium cooperi Arnold, U. S. Geol. Surv., Bull. 39tj, p. 94, pi. 30, figs. 2, 2a, January 15, 1910; Arnold and R. Ander- son, Bull. 398, pi. 52, figs. 2, 2a, 1910; Hannibal, Proc. Malae. Soe. London, Vol. 10, p. 131, 1912. Type specimen: U. S. National Museum, No. 165,528. Type locality: Near Kettleman Hills, Coalinga district, California; base of the Tulare formation, fresh-water Pleistocene. Pleistocene: At the type locality, lower Pleistocene. The cardinal teeth of this species are very thin, elongate, and approximately parallel to the hinge margin. Superfamily Erycinacea Family ERYCINIDAE Genus ERYCINA Lamarck, 1805 Erycina Lamarck, Ann. Mus. Hist. Nat. Paris, Vol. 6, p. 413, December, 1805, list includes E. pellucida but not E. cardioides; Froriep, Neues Syst. Conch., p. 38, 1807; Children, Quart. Jour. Sci., Lit., Arts, Vol. 14, p. 299, 1823, "type" E. cardioides Lamarck; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 263, 1871, type, E. pellucida, Lam.; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1140, 1141, 1900. Type (by subsequent designation, Stohczka, 1871), Erycina pellucida Lamarck, op. cit., p. 414, 1805, figured by Cossmann and Pissarro, Icon. Coq. Fos. Eoc. Env. Paris, pi. 27, fig. 88-1, 1906, Eocene of the Paris basin. Shell small, smooth, or concentrically sculptured; hinge with small cardinal teeth, laterals long, stronger distally; resiliiim in a fosette between the cardinal teeth. This genus occurs in the Eocene of Europe and is represented in the Recent fauna of the Pacific coast. It has not yet been reported from the Pliocene or Pleistocene of Cali- fornia, but can be expected to occur there. We use the family name Erycinidoe, based upon the oldest described genus, in place of Leptonidce. Genus CHIRONIA Deshayes, 1839 Chironia Deshayes, Rev. Zool. Soc. Cuv., p. 356, 1839; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 264, 1871; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1153, 1900, in synonymy of Kellia. "Kellia Turton," Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1153, 1900; and of various other authors. Type (fide Dall, 1900), C. laperousii Deshayes. Shell ovate, subglobose; hinge with two cardinals in each valve, a large posterior and a small anterior right cardinal, and a small posterior and a large anterior left cardinal; a posterior but no anterior lateral; pallial line entire. Size generally small, length varying up to about 40 mm. Chironia suborbicularis (Montagu) Mya suborbicularis Montagu, Test. Brit., pp. 39, 564, 1803. Tellina suborbicularis Montagu, Turton, Conch. Diet., p. 179, 1819. Kellia suborbicularis Montagu, Turton, Conchyl. Insul. Brit., Dithyra, p. 56, pi. 11, figs. 5, 6, 1822; Forbeg and Hanley, Hist. Brit. Moll., Vol. 2, p. 87, pi. 18, figs. 9, 9a, 9b, and pi. O, fig. 4, 1853. Tellimy a suborbicularis Montagu, Brow-n, lUust. Conch. Gt. Brit., Ed. 2, p. 106, pi. 42, figs. 14, 15, 1844. Type locality: England; Recent. The English variety averages a little smaller than the Pacific coast variety, but the two forms are very similar. The former is well figured by Forbes and Hanley. 300 San Diego Society of Natural History [Memoirs Chironia suborbicularis (Montagu) variety laperousii Deshayes Plate 14, Figures 19a, 196 Chironia laperousii Deshayes, Rev. Zool. Soe. Cuvierienne, Vol. 2, p. 357, 1839. "Kellia suborbindaris Montagu," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 553, 602, 611, 620, etc., 1864; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 137, pi. 18, figs. 1, la, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 36, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 131, 1924; apparently not typical of Montagu's British species. Bornia luticola Valenciennes, in Du Petit-Thours, Voy. Venus, Atlas, pi. 24, 1816. Kellia laperousii Deshayes, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 643, 1864; Newcombe, Bull. Nat. Hist. Soc. Brit. Columbia, p. 49, 1893; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1155, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 137, pi. 18, figs. 7, 7a, 1903; Dall, Bull. 112, U. S. Nat. Mus., p. 36, 1921; Dall, in Orcutt, West American Scientist, Vol. 19, No. 3, p. 23, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 152, 153, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 131, pi. 10, fig. 2, pi. 33, fig. 4, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 5, 1925; Yokoyama, Jour. Faculty Sci., Imper. Univ. Tokyo, Sect. 2, Vol. 1, pt. 9, p. 386, pi. 44, fig. 8, 1926. Kellia rotundata Carpenter, Jour, de Conchy!., Vol. 12, p. 137, April, 1865; Monterey. Pleistocene: "Pliocene" of Deadman Island, one valve; lower San Pedro series of San Pedro and Deadman Island, rare (Arnold) ; lower San Pedro series of Nob Hill cut, San Pedro, "six valves" (T. S. Old- royd); Pleistocene of Spanish Bight, San Diego (Arnold); lower Pleistocene at Magdalena Bay, and upper Pleistocene at San Quintin Bay, Lower California (Jordan); Pleistocene of Japan (Yoko- yama); etc. Recent: Bering Sea and Pribilof Islands to Panama. The Pacific coast shells assigned to siiborbicularis and laperousii appear to represent one variable species, which averages larger than the British C. suhorbicularis (Montagu). The synonymy given above is very much abbreviated. Genus ALIGENA Lea, 1843 Aligena H. C. Lea, Proc. Amer. Philos. Soc, Vol. 3, p. 163, 1843, -4. striata and ,4. teis only .species; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1175, 1900. Type (by subsequent designation, Dall, 1900), Aligena striata H. C. Lea. According to Dall, "the characteristic of this group is the possession of a rounded triangular inflated shell with only a single small anterior tooth under the beaks separated by a gap from the surface of attachment, under the posterior dorsal margin, of an elongate internal resilium carrying a lithodesma. The pallial line is simple, and the cardinal of the left valve more feeble than the other." Aligena cerritensis Arnolci Aligena cerritensis Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 138, pi. 13, fig. 3, 1903; Dall, Nautilus, Vol. 32, p. 24, 1918; Bull. 112, U. S. Nat. Mus., p. 36, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 132, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: U. S. National Museum, Cat. No. 162,529. Type locality: Los Cerritos (Signal Hill), near Long Beach, Los Angeles County; Pleistocene. Pleistocene: Upper San Pedro of Los Cerritos, type locality, two specimens (Arnold); Magdalena Bay Pleistocene, Lower California, Mexico (Dall, 1918); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: La Jolla to Magdalena Bay (Dall, 1921). This species has a small shell (about 11 mm. in length), somewhat broadly truncated on one end. Volume 1 ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 301 Genus ROCHEFORTIA Velain, 1877 Rochefortia C. Velain, Archives de Zoologie experimentale et gencrale, Paris, Vol. 6. pp. 132, 133, pi. .5, figs. 9-11, 1877, only species, R. australis Velain; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 11.57-59, 1900. Type (by monotypy), Rochefortia australis Velain, op. cit., p. 133, pi. 5, figs. 9-11, 1877; St. Paul Island, south Indian Sea; Recent. Dall has given a good discussion and description of this group, and the monotype was well figured by Velain. It is Tellimya, as used by Carpenter, and Mysella Aiigas, 1877, but only in part TeUivnja Brown. Rochefortia tumida (Carpenter) Plate 14, Figures 16, 17 Tellimya tumida Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 643, 1864. Mysella tumida Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 21, p. 892, pi. 87, fig. 7 (Carpenter's type specimen), 1899. Rochefortia tumida Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 37, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 132, pi. 54, figs. 11-14, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In the U. S. National Museum, Cat. No. 5,242. Type locality: Vancouver Island, British Columbia; Recent. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico. Recent: Shumagin Islands, Alaska, to San Diego, California (Dall, 1921). Genus BORNIA Philippi, 1836 Bornia Philippi, Enum. Moll. Sicilise, Vol. 1, p. 13, 1836; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, pp. 265, 266, 1871; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1147, 1148, 1900. Type (by subsequent designation, Stohczka, 1871), Bornia corbuloides Philippi, op. cit., p. 14, 1836, Mediterranean; Recent (according to Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. RoussiUon, Vol. 2, pp. 235, 236, pi. 39, figs. 1, 2, 1892 = Cyclas sebatia da Costa, 1829). This genus appears to be close to several other named groups. When the family is critically reviewed it is likely that a number of changes in nomenclature will be required, Bornia retifera Dall Bornia retifera DaU, Proc. U. S. Nat. Museum, Vol. 21, p. 889, pi. 87, fig. 2, 1899; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 136, pi. 17, fig. 12, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 38, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 137, 1924. Pleistocene: Lower San Pedro series of Deadman Island, San Pedro Harbor, Los Angeles County, "one right valve" (Arnold). Recent: Monterey to Santa Barbara Islands, California (Dall). Genus KELLIA Turton, 1822 Kellia W. Turton, Conch. Insul. Brit., pp. xix, 56, 1822, Kcllia suborbicularis (Montagu), and K. rubra (Montagu) included; Herrmannsen, Indieis Gen. Malac, Vol. 1, p. 568, 1847, "Typus: Cardium rubrum Mont." Lasxa Leach, in Brown, 111. Conch. Gt. Brit., Ed. 1, pi. 20, figs. 17-18, 1827; Ed. 2, p. 93, pi. 36, figs. 17-18, 1844, sole e.xample, L. rubra (Montagu); Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1162, 1163, 1900. Shell very small; hinge variable, rather crude; animal nestling in habit. Herrmannsen fixed the type of Kellia Turton, on Cardium rubrum Montagu, which species later served as the sole example of Lascea Leach, in Brown, 1827. Thus, it is 302 San Diego Society of Natural History [ Memoirs necessary to use Kellia for the small nestlers which have been called Lascea, and for the Kellias of the suborbicularis type the name Chironia Deshayes is to be used. These changes, though disconcerting to many, are in accord with the International Code, and as long as the rules are to be followed the sooner such disagreeable rearrangements are made the better. Kellia rubra (Montagu) Cardium ruhrurn Montagu, Test. Brit., p. 83, pi. 27, fig. 4, 1804. Kellia rubra Montagu, Turton, Conch. Ins. Brit., pp. 57, 58, pi. 11, figs. 7, 8, 1822. Lassea rubra Montagu, Brown, III. Conch. Gt. Brit., Ed. 1, pi. 20, figs. 17, 18, 1827; Ed. 2, p. 93, pi. 36, figs. 17, IS, 1844; Dall, Bull. 112, U. S. Nat. Mus., p. 38, 1921; Dall, in Orcutt, West American Scientist, Vol. 19, No. 3, p. 23, June, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 138, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In the British Museum. Type locality: British coast. Pleistocene: San Quintin Bay, Lower California, Mexico (Dall, in Orcutt). Recent: Vancouver Island, British Columbia, to Callao, Peru; also .Atlantic. This small shell is a nestler, often found in the byssal threads of mussels or in cracks in rocks. Superfamily Cardiacea Lobes of the mantle free behind the siphons, foot elongate, geniculate; sculpture of the shell chiefly radial; cardinal teeth conical, the lateral laminae short, distant from the cardinals. (Dall.) Family CARDIIDAE Shell substance cellulo-crystalline, with the external layer more or less tubular; valves equal, free, gaping slightly behind, the beaks inclined slight!}' forward, the margins usually serrate or rad- ially striated; adductor scars subequal, the pedal distinct and usually distant; ligament and resilium short, external, set iii a groove ; cardinal area obscure ; complete hinge armature consisting of an an- terior and a posterior lateral tooth in the left valve, two anterior and one posterior lateral in the right, any or all of which may be absent, and one cardinal in each valve, usually persistent and well de- veloped; all of the teeth simple, smooth, never bifid. (After Dall.) Geologic range: Triassic to Recent. Distribution : Cosmopolitan. Genus CARDIUM Lmnaeus, 1758 Cardium Linnaeus, Syst. Nat., Ed. 10, p. 678, 1758, C. costatum, first species; Children, Quart. Jour. Sci., Lit., Arts, Vol. 14, p. 315, pi. 6, fig. 59, 1823; Gray, Proc. Zool. Soc. London, Pt. 15, p. 185, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1069, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 383, Jan. 2, 1901; Woodring, Carnegie Inst., Publ. No. 366, p. 134, 1925. Tropidocardium Roemer, Neues Syst. Conch. Cab., Ed. 2, Cardium, p. 13, 1869; Dall, 1900; and others. Type (by subsecjuent designation, Children, 1823), Cardium costatum Linnseus; Indo-Pacific region; Recent. Shell large, globose, thin for its size, strengthened by a few high, thm, shellj' projections or radial costse; hinge line straight; siphonal gape wide. A large number of species differing markedly in character from C. costatum have been assigned traditionally to the genus Cardium. However, a study of C. costatum which Children and others have clearly designated as the genotype, shows that it is hardly pos- Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 303 sible to use the well-known name Cardium any longer for the majority of the species to which it has been applied. C. costatum is a peculiar form, sculptured with but a few, knife-like ridges that rise more than a quarter of an inch above the smooth general surface of the shell. It differs from the normal Carrfmm-like species as radically in other char- acters as in sculpture. Cardium aculeatum Linnaeus has often been considered the geno- type because it was selected as an example of the genus by Lamarck in 1799; but La- marck's action does not constitute designation of type, and however much we might wish to use aculeatu77i for the type, we cannot do it. Furthermore, aculeatum is not a normal member of the group that we should Uke to call Cardium, but belongs to Acanthocardia Gray,^ of which it is the type. Most of the species from the Pacific coast of North America that have been known as Cardium will fall within a single genus, Lwvicardiurn. Genus LAEVICARDIUM Swainson, 1840 ? Didacna Eichwald, Bull. Soc. Imp. Nat. Moscou, p. 166, 1838, species included, Cardium trigonoides Pallas and Cardium crassum Eichwald = C. eichwaldi Ivryn. (Bull, des Xatur. de Moscou, No. 2, p. 61, 1837); Recent, Caspian Sea. ? Monodacna Eichwald, op. cit., p. 167, 1838. Lxvicnrdium Swainson, Treat. Malac, p. 373, 1840; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 209, 1871; Bucquoy, Dautzenberg, and DoUfus, 1887; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1076, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 384, 1901; Woodring, Carnegie Inst., Publ. No. 366, p. 144, 192.5. lAocardium Morch, Cat. Conch. Yoldi, Pt. 2, p. 35, 1853, as of Swainson. Type (by subsequent designation, Bucquoy, Dautzenberg, and DoUfus, 1887), Cardium europceum Wood = C. norvegicum Spengler, European and Mediterranean. Shell quadrate or subtriangular, inflated, comparatively heavy, radiately ribbed or striated; hinge normal, hinge line curving; without appreciable posterior gape. Most of the species formerly called Cardium are closely related and fall naturally into a single genus. The earliest name available for this group is, apparently, Lcevicardium ; and although the meaning of the name might be misleading, the group of species can be thought of as ha\'ing lower, less angular, and in that sense more nearly smooth sculpture than Cardium. Eichwald's names would be much more appropriate; but they are based on speciahzed Caspian Sea species, and without figures or specimens the writers do not feel justified in introducing them. It is possible that the Caspian species have changed only a httle in the short time since the Caspian Sea has been separated from the open ocean, and that Didacna or Monodacna could be used in a broad sense in place of LcBvi- cardium.^ Only in the typical subgenus of Lcevicardium, as here used, is the ribbing obsolete or nearly obsolete. The other subgenera usually have ribs; but the ribs are usually more numerous, smaller, lower, blunter, and stouter than in true Cardium. Lcevicardium can also be distinguished from Cardium by its curved hinge fine, simpler teeth, smaller pos- terior gape, and usually heavier shell. Liocardium is an emendation by Agassiz for Lcevicardium Swainson. The altered spelUng was used by Morch, 1853, Carpenter, 1864, and others. 1 List of Specimens of British Animals in the Collection of the British Museum. Pt. 7, p. 23, 1S51, type cited by Bucquoy, Dautzenberg , and Dollfus, 1S87, fide Woodring, 1925. ' See Bateson. W.: "On Some Variations of Cardium edule apparently Correlated with the Conditions of Life," Philosophical Transactions of the Royal Society of London for the year 1889. Vol. ISO. Part B, pp. 297-330, with msps and diagrams. 1890. Bateson follows the changes in characters shown by this species as a result of the increasing salinity of the Aral Sea during the Pleistocene. 304 San Diego Society of Natural History [ Memoirs Subgenus LAEVICARDIUM, s. s. Shell of relatively great altitude, valves closed; middle of the valves smooth or feebly radially sculptured, ends with smooth areas; hinge normal, but with the anterior lateral teeth rising from the umbonal cavity; periostracum smooth. Laevicardium (Laevicardium) elatum (Sowerby) Cardium elatum G. B. Sowerby, Proc. Zool. Soc. London, Pt. 1, p. 84, Sept., 1833; Conch. Illust., Cardium, fig. 3, 1834; Reeve, Conch. Icon., Vol. 2, Cardium, pi. 8, fig. 41, 1844; Valenciennes, Voy. Venus, Atlas Zool., Moll., pi. 17, fig. 1, 1846; Romer, in Martini und Chemnitz, Conch. Cab., Ed. 2, Cardiacea, p. 93, pi. 13, fig. 7, 1869, Mabille, Bull. Soc. Philomathique de Paris, Ser. 8, Vol. 7, p. 74, 1895; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924. Cardium (Lsevicardium) elatum, Sowerby, Carpetner, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 91, 1857; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 391, 1901; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 141, pi. 20, 1903; Lamy, Journ. de Conchyl., Vol. 57, p. 235, 1909; Dall, U. S. Nat. Mus., Bull. 112, p. 40, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 144, 1924. Liocardium elatum Sowerby, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 642, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 246, 1888; Keep, West Coast SheUs, p. 181, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 190, 1892. Lsevicardium elatum Sowerby, Gabb, Geol. Surv. Calif., Palao., Vol. 2, p. 99, 1868-9; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1111, 1900. Cardium {hiocardium) elatum Sowerby, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 151, 1894. Type specimen: In the British Museum. Type locality: Gulf of California; Recent. Pleistocene: Lower Quaternary of Magdalena Bay, Lower California, Me.xico (Jordan) ; upper San Pedro series at the north end of San Pedro Bluff and at Los Cerritos, Los Angeles County; Pleistocene at San Diego (Gabb; DaU, 1900). Recent: San Pedro, California, to Panama (Dall, 1921). This is an enormous species, with a nearly smooth surface. It is a warm-water shell, occurring in the warm-water upper San Pedro series, now called the Palos Verdes forma- tion, but not found in the cold-water horizons of the California Pleistocene. Laevicardium (Laevicardium) substriatum (Conrad) Cardium substriatum Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, p. 228, pi. 17, fig. 2, 1837; Keep, West Amer. Shells, p. 62, 1904; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 563, 1922; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 251, 1929. Liocardium substriatum Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 642, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 246, 1888; Keep, West Coast Shells, p. 181, fig. 154, 1888, 1892; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, p. 190, 1892. Lsevicardium substriatum Conrad, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 99, 1868-9; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1111, 1900. Cardium {Lsevicardium) substriatum Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 391, 1901; U. S. Nat. Mus., Bull. 112, p. 40, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 145, 1924. Type locality: Vicinity of San Diego, California; Recent. Pleistocene: Lower San Pedro scries of Deadman Island and San Pedro, rare (Arnold, 1903) ; lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan, 1924) ; Tomales Bay, Marm County (Dicker- son); foot of Twenty-sixth Street, San Diego (Arnold; Frank Stephens); upper San Pedro series of Deadman Island, San Pedro, Crawfish George's, and Los Cerritos (Arnold) ; upper Quaternary at San Ignacio Lagoon and San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926). Recent: Catalina Island and San Pedro, California, to Acapulco, Mexico (Dall). Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 305 This is a small species with a smooth surface. It is closely related to L. elenense (Sowerby)' of the Panama fauna. It is similar in some respects to the young of L. elatum; but immature specimens of Recent eJatum are mottled with a purple or pink color, whereas substriatuni is whitish. L. apicinu7n (Carpenter)-, the type locality of which is Cape San Lucas, is also closely related, but seems to be a smaller, higher-beaked, smoother race than typical substriatuni. It may be possible to retain the two southern forms in the nomenclature as varieties. Subgenus MEXICARDIA Stewart, 1930 Mericardia Stewart, Special Publ. No. 3, Proc. Acad. Nat. Sei. Phila., p. 263, 1930. Type (by original designation), Cardium procerum Sowerby. Shell of relatively great altitude, with few, coarse, squarish ribs. Unlike Ringicardium, Mexicardia is probably closely related to Lmvicardium and its other subgenera. Laevicardium (Mexicardia) procerum (Sowerbj-) Cardium -procerum Sowerby, Proc. Zool. Soc. London, Pt. 1, p. 83, 1833; Conch. lUust., Cardium, fig. 23, 1834; Reeve, Conch. Icon., Vol. 2, Cardium, pi. 10, fig. 51, 1844; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 91, 1857; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 150, 1894; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1091, 1900; Proc. U. S. Nat. Mus., Vol. 37, p. 157, 1909; McLaughlin and Waring, Calif. State Mining Bureau, Map Folio accompanying Bull. 69, pi. 1, fig. 53, 1914; Dall, Nautilus, Vol. .32, p. 24, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 148, 151, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Cardium laticostatum Sowerby, Proc. Zool. Soc. London, Pt. 1, p. 85, 1833; Conch. lUust., Vol. 1, fig. 30, 1834 (date ?). Cardium panamense Sowerby, Proc. Zool. Soc. London, p. 85, 1833; Conch. lUust., Vol. 1, fig. 21, 1834 (?); Reeve, Conch. Icon., Vol. 2, Cardium, pi. 11, fig. 56, 1844; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 74, 1895. Cardium subelongatum Valenciennes, Voy. Venus, Atlas Zool. Moll., pi. 17, fig. 2, 1846, not of Sowerby, /ide Lamy, 1909. Cardium rotundatum Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 531, 1857, fide Lamy, 1909. Cardium {Ringicardium) procerum Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 389, 1901; Lamy, Jour, de Conchyl., Vol. 57, p. 233, 1909; Dall, Bull. 112, U. S. Nat. Mus., p. 39, 1921 (subgenus cited questionably). Type locality: Real Llegos, Central America. Pleistocene: Lower San Pedro series of Deadman Island, San Pedro, "one specimen" (Arnold); lower Quater- nary at Magdalena Bay, Lower California, Mexico (Dall, 1918; Jordan, 1924); Spanish Bight and foot of Twenty-sixth Street, San Diego (Arnold); "rather common in the upper San Pedro series of San Pedro, Long Beach, and Los Cerritos (Arnold); upper San Pedro series of Santa Monica (in Oldroyd Collection at Stanford University); upper Quaternary at San Ignacio Lagoon (Jordan, 1924) and upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Scammon Lagoon, Lower California, Mexico, to Peru (Jordan, 1924). This is the common rotund, spiny Lcevicardium of the Lower California coast. Subgenus TRACHYCARDIUM Miireh, 1853 Trachycardium Morch, Cat. Yoldi, Pt. 2, p. 34, 1853, list includes C. isocardia Linnaeus; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 207, 1871; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1073, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 383, Jan. 2, 1901; Woodring, Carnegie Inst., Publ. No. 366, p. 135, 1925. Granocardium Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 266, 1868-9. Type (by subsequent designation, Dall, 1901), Cardium isocardia Linnseus, West Indies; Recent. ' Proc. Zool. Soc. London, Pt. 8, p. 109. May, 1841. ' Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 313. April, 1S64. 306 San Diego Society of Natural History [ Memoirs Shell quadrate; ribs with spines characteristically only on one edge of each rib; valves closed or nearly closed. As pointed out by Stoliczka, Granocardium Gabb is a needless name. Laevicardium (Trachycardium) censors (Sowerby) Cardium consors G. B. Sowerby, Proc. Zool. Soc. London, Pt. 1, p. 85, September, 1833; Sowerby, Conch. lUust., Cardium, fig. 8, 1834; Sowerby in Reeve's Conch. Icon., Vol. 2, Cardium, pi. 17, fig. 86, 184.5; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1856, p. 307, 1857; Romer, in Martini und Chemnitz, Conch. Cab., Ed. 2, Cardiacea, p. 48, pi. 10, figs. 6, 7, 1869; Stearns, Proc. IT. S. Nat. Mus., Vol. 17, p. 150, 1894; Mabille, Bull. Soc. Philomathique de Paris, p. 74, 1895; Lamy, Jour, de Conchyl., Vol. 57, p. 233, 1909; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, Pt. 5, p. 148, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 140, 1927. Cardium (Trachycardium) consors Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 389, January 2, 1901; Vol. 37, p. 264, 1909 (as of Broderip and Sowerby). Pliocene: Coronados Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary of Magdalena Bay, Lower California, Mexico (Jordan); one valve from the Pleistocene of the Santa Rosalia district (collected by M. E. Touwaide). Recent: Gulf of California, Mexico, south to Guayaquil and the Galapagos Islands. This southern shell has been well illustrated. A variety with the imbrications twice as distant from each other and more elongated Dall has named laxum. Laevicardium (Trachycardium) quadragenariimi (Conrad) Plate 19, Figure 15 Cardium quadragenarium Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 230, pi. 17, fig. 5, 1837; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 232, 1888; Williamson, Proc. U. S. Nat. Museum, Vol. 15, p. 190, 1892; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1091, 1900; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 28, pi. 5, fig. 1, 1920. Cardium quadrigenarium Conrad, Keep, West Coast Shells, p. 192, 1888, 1892; West American Shells, p. 63, 1904; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 417, 1915; Martin, Vol. 9, p. 251, 1916; Nomland, Vol. 10, pp. 218, 300, 1917; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 563, 1922; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 6, 1925. Cardium (Trachycardium) quadragenarium Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 389, 1901; Bull. 112, U. S. Nat. Mus., p. 39, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 141, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Shell cordate, subequilateral, ventricose, thick; ribs forty to forty-two, prominent, subangular, flattened at the sides, with a series of small spines which on the middle and posterior parts of the shell are conspicuously placed on the posterior angular margin of the ril)s; umbones broad, prominent; beaks not oblique; color pale yellow, with fulvus spots and zones; posterior margin direct, deeply serrate. Height, three mches, according to Conrad. Type locality: Near Santa Barbara, California; Recent. Miocene: "Vaqueros-Temblor" (probably Temblor middle Miocene); Santa Margarita formation, upper Miocene, north of Coalinga (Nomland); upper and lower San Pablo, upper Miocene of middle California (Clark). Pliocene: Jacalitos (Clark) and Etchegoin formations near Coalinga (Nomland) ; Pico near Ventura (Water- fall); lower part of Merced formation south of San Francisco (Martin); Calleguas Ranch, Ventura County (Cooper). Pleistocene: Lower San Pedro formation of Nob Hill cut, San Pedro (T. S. Oldroyd) ; Tomales Bay, Marin County (Dickerson); Pleistocene of Pacific Beach and at the foot of Twenty-sixth Street, San Diego (Arnold); "upper San Pedro series of San Pedro, Los Cerritos and Long Beach Bluff," Los Angeles County (Arnold); "Saugus" formation near Ventura (Waterfall); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to Todos Santos Bay, Lower California, Mexico (Dall, 1921). According to Dall, 1901, Cardium luteolabrum Gould, 1851, C. xanthocheilum (Gould MS.) Carpenter, 1856, C. arenatum Carpenter, 1857, and C. setosum Tryon, 1872, not Redfield, 1846, are synonyms. Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 30( Laevicardium (Trachycardium) quadragenarium (Conrad) variety femandoense (Arnold) Cardium quadrigmarium Conrad, vslt. femandoensis Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 535, pi. 48, figs. 2, 2a, 1907; English, Univ. Calif. Publ. Geol., Vol. S, p. 209, 1914. Type specimen: In the V. S. National Museum, Cat. No. 164,947. Type locality: Elsniere Canyon, two and a half miles southeast of Newhall, Los Angeles County, California. Pliocene: T>T3e locality (Arnold) ; Elsmere and Pico canyons, Los .\ngeles County (English). According to Arnold, "This variety is more obhque, has narrower umbones, is rela- tively less in diameter, and has fewer and less prominently spinose ribs than the typical form." It is likely that some of the occurrences listed under the typical form refer to this variety. Cardivm vaqtierosense Arnold' from the lower Miocene of Kern and San Mateo coun- ties and from the Temblor formation- of Orange County also belongs to this subgenus. The section AcrosterigmaDaW^ is characterized by having an internal elevated mesial rib radiating from the umbonal cavitJ^ Subgenus CERASTODERMA Poli in Morcli, 1853 Cerastoderma Poli, Morch, Cat. Conch. Yoldi, Pt. 2, p. 34, 1853, list includes C. edule Linnaeus, and others; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 208, 1871; Meek, Kept. U. S. Geol. Surv. Territories, Vol. 9, p. 166, 1876; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1073, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 384, 1901. Type (by subsequent designation, Stoliczka, 1871), Cardiu7n. edule Linnaeus; Euro- pean seas; figured in Reeve, Conch. Icon., Vol. 2, Cardium, pi. 4, fig. 22, 1844. Shell more or less quadrate in shape, closed; with strong ribs that are granulose or smooth but not spinose; no posterior or anterior cardinal area: chamiels simple; hinge normal. According to Stoliczka, this subgenus begins in the Cretaceous. Laevicardium (Cerastoderma) corbis (Martyn) Plate 19, Figures 14, 17 Cochlea corbis Martyn, Univ. Conch., Vol. 2, fig. 80, 1788. Cardium nuttallii Conrad, Jour. Acad. Nat. Sci. Phila., Vol. 7, p. 229, pi. 17, fig. 3, 1838; Reeve, Conch. Icon., Vol. 2, Cardium, pi. 13, fig. 66, 1845; Amer. Jour. Conch., Vol. 5, \:t. 2, p. 105, 1869. Cardium nutlallianum Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 192, 1857. Cardium corbis Martyn, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 642, 1864; Conrad, Amer. Jour. Conch., Vol. 5, Pt. 2, p. 105, 1869; Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 207, pi. 4, fig. 36, 1909; Thompson, Report of the B. C. Commissioner of Fisheries for 1912, pp. 1-39, 1-47, pis. 3, 4, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 417, 1915; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. .32, 1916; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 251, 1916; Nomland, Vol. 10, p. 218, 1917; Edmondson, Science, N. Y., Vol. 49, p. 402, 1919; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 28, pi. 5, fig. 2, 1920; Dall, Amer. Jour. Sci., Ser. 5, Vol. 4, p. 310, 1922; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 563, 1922. Cardiurn {Cerastoderma) corbis Martyn, Dall, Proc. U. S. Nat. Museum, Vol. 23, p. 390, 1901; .\rnold, Mem. Calif. Acad. Sci., Vol. 3, p. 140, 1903; Dall, Bull. 112, U. S. Nat. Mus., p. 39, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 142, pi. 34, figs, la, 15, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 6, 1925. ' Proc. U. S. Nat. Museum, Vol. 34, p. 378, pi. 34, fig. 3, 1908; U. S. Geol. Surv.. Bull. 396. pi. 9, fig. 2, Jan. 15, 1910. » Univ. Calif. Publ. Geol., Vol. 15, p. 208, 1925. • Trans. Wagner Inst. Sci., Vol. 3, p. 1073, 1900, type designated C. dalli Heilprin. 308 San Diego Society of Natural History [ Memoirs Miocene: Montesano formation of western Washington (Weaver); Quillayute formation of the Olympic Peninsula (Reagan); San Pablo formation, upper Miocene of middle California (Clark); Empire formation of Coos Bay, Oregon (Dall, 1909; Howe). Pliocene: Merced and Purisima formations of the coast of middle California (Martin); Etchegoin formation of the Coalinga district (Nomland, 1917); Southern California Gas Company's well, No. 1-4, Sec. 4, T. 28 S., R. 23 E., Kern County, depth, 3969 feet, three specimens, upper Etchegoin (H. R. G.); Bath-house Beach, upper Pliocene, Santa Barbara (Arnold, 1903). Pliocene or Pleistocene: Coos conglomerate of Coos Bay, Oregon (Dall, 1909; Howe). Pleistocene: Tomales Bay, Marin County (Dickerson); lower San Pedro series of Deadman Island and San Pedro (Arnold, 1903); of Nob Hill cut, San Pedro, quite plentiful (T. S. Oldroyd). Recent: Nunivak, Pribilof, and Commander islands, Bering Sea, south to Hakodate, Japan, and to San Diego, California; ? Lower California (Dall, 1921). This is a rather large species, with about thirty-seven prominent, closely-set, some- what rugose ribs. It is larger and has wider ribs than L. decoratum (Grewingk). Laevicardium (Cerastoderma) corbis (Martyn) variety coosense (Dall) Cardium (Cerastoderma) coosense Dall, U. S. Geol. Surv., Prof. Paper 59, p. 118, pi. 13, figs. 3, 4, April 2, 1909. Cardium coosense DaU, Arnold, U. S. Geol. Surv., Bull. 396, p. 30, January 15, 1910; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 590, 1913; Howe, Univ. Calif. Publ. Geol., Vol. 14, table opp. p. 92, 1922; Dall, Amer. Jour. Sci., Ser. 5, Vol. 4, p. 310, 1922. Cardium coosensis Dall, Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 32, 1916; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 251, 1916. Type specimen: In the U. S. National Museum, No. 153,933. Type locality: Coos Bay, Oregon; Miocene. Miocene: Empire formation, Coos Bay, Oregon (Dall; Arnold and Hannibal; etc.); Montesano formation of western Washington (Weaver); Wildcat formation of northern California (middle Wildcat, Martin; upper, Howe). Pliocene: Etchegoin formation of Coalinga region (Arnold, 1910); Merced-Purisima Pliocene near San Fran- cisco. Pliocene or Pleistocene: Coos conglomerate, Coos Bay, Oregon (Howe). Dall gives a detailed description of this form and remarks further: "Although the specimens are far from perfect, the species cannot be referred to any previously known from the coast. The ribs are more compact, more numerous, and less prominent than in C. ciliatum Fabricius or C. corbis Martyn; the shell is more ovate than in C. californiense or its variety comoxense; the ribs are much more numerous and the interspaces less channelled than in C. decoratum; C. meekianum is much more oblique and has the sculp- ture absent on the submargins; its ribs are also fewer." However, it seems to the present writers doubtfully distinct. Laevicardiuin (Cerastoderma) decoratum (Grewingk) Plate 19, Figure 12 Cardium decoratum Grewingk, Russisch-Kaiserliche Mineralogische Gesellschaft zu St. Petersburg, Verhandlungen for the years 1848 and 1849, p. 347, pi. 4, figs. 2a-g, 1850; Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 844, 1896; Dall, in Spurr, 20th Ann. Rept., Pt. 7, p. 264, 1900; Washington Acad. Sci., Alaska., Repts. Harri- man Alaska Expedition, Vol. 4, pp. 114, 121, 1904, reissued by the Smithsonian Institution, 1910. Cardi%m (Cerastoderma) decoratum Grewingk, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 390, 1901; U. S. Geol. Survey, Prof. Paper 59, p. 119, 1909; U. S. Nat. Mus., BuU. 112, p. 39, 1921. Type locality: Alaska; Tertiary. Miocene: "Tertiary" of Unga, Kadiak, Aliiksa, Atcha, St. Paul, in "vulkanischen (?) tuff" (Grewingk); "Miocene" of St. Paul Island, Atka Island, Pavloff Bay, Unga Island, Kaliak Island, also Miocene of British Columbia (Dall, 1896); Cape Yaktag, Alaska (Dall, 1900); Miocene of Coos Bay, Oregon (Dall, 1909). Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 309 Pliocene: St. Paul Island, Bering Sea (Dall, 1904-10). U. Pliocene or Pleistocene: Elk River Beds, Oregon. Pleistocene: Boulder clays of Alaska and British Columbia (Dall, 1909); Douglas Island, near Juneau, Alaska (Dall, 1904). Recent: (?). Lcevicardium decoratum (Grewingk) is very close to L. corbis (Martyn), 1788, but ap- pears to be smaller and to have narrower ribs. There are about twenty-eight to thirty flat-topped ribs about as wide as the interspaces.^ Laevicardium (Cerastoderma) califomiense (Deshayes) Plate 19, Figures 13, 16 Cardium califomiense Deshayes, Rev. Zool. Soc. Cuv., Vol. 2, p. 360, December, 1839; Guerin, Mag. Zool., Moll., pi. 47, fide Dall, 1921; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1093, 1900; Jour. Wash. Acad. Sci., Vol. 9, p. 2, 1919; Howe, Univ. Calif. Publ. Geol., Vol. 14, opp. p. 92, 1922. Cardium pseudo-fossile Reeve, Conch. Icon., Vol. 2, Cardium, pi. 10, fig. 52, Dec, 1844. Cardium blandum Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 276, 1851. Cardium {Cerastoderma) califomiense Deshayes, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 390, 1901; Bull. 112, U. S. Nat. Mus., p. 39, pi. 14, fig. 8, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol,, Vol. 1, p. 143, pi. 2, fig. 3, 1924. Cardium fucanum Dall, Nautilus, Vol. 20, p. 112, 1907. Cardium (Cerastoderma) fucanum Dall, U. S. Nat. Mus., Bull. 112, p. 39, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 143, 1924. Type locality : Puget Sound ; Recent ( fide Oldroyd) . ? Miocene: Empire formation of Oregon (Howe) . Pliocene: St. George Island and St. Paul Island, Pribilof group (Dall, 1909); Pliocene of California (Dall, 1900). Pliocene or Pleistocene: Coos conglomerate of Coos Bay, Oregon (Howe). Recent: Arctic Ocean to San Diego, California; North Japan and Okhotsk Sea (Dall, 1921). This species is well figured by Reeve (as pseudo-fossile) , by Dall, and by Oldroyd. It is another member of the closely related corbis group. It has from forty to fifty rounded, generally rather smooth ribs. Laevicardium (Cerastoderma) califomiense (Deshayes) variety comoxense (Dall) Cardium califomiense Deshayes, var. comoxense Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1093, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 390, 1901. Cardium (Cerastoderma) califomiense comoxense Dall, U. S. Nat. Mus., Bull. 112, p. 39, 1921. Type specimen: In the U. S. National Museum. Type locality: Vancouver Island, boulder clay of Pleistocene age. Pleistocene: At the type locality (Dall). Dall separated this variety from the typical because "the ribs are much depressed and flattened, and the interspaces reduced to narrow, shallow grooves." It is possible that erosion would give the ribs a peculiar aspect, but the present authors have not seen specimens of Dall's variety. 1 Eichwald, p. 129, 1871, attributes Grewingk's original specimens to the Cretaceous and thinks they might be the same as Pectunculus umbonatu^ Sowerby. See the note on Mya arenaria variety pro/uitdior, p. 41-1. 310 San Diego Society of Natural History [Memoirs Laevicardium (Cerastodenna) meekianum (Gabb) Cardium meekianum Gabb, Geol. Surv. Calif., Palseo., Vol. 2, ji. 27, pi. 7, fig. 46, 1866; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 232, 1888; Dall, IT. S. Geol. Surv., Prof. Paper 59, p. 119, 1909; Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 206, pi. 4, fig. 35, 1909, probably only in part; Arnold, U. S. Geol. Surv., Bull. 396, pp. 25, 140, pi. 17, fig. 7, January 15, 1910; Arnold and .\nderson. Bull. 398, pp. 108, 125, 312, pi. 39, fig. 7, 1910; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 590, 592, 594, 1913; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 251, 1916; Howe, Vol. 14, table opp. p. 92, 1922; Dall, Amer. Jour. Sci., Ser. 5, Vol. 4, p. 310, 1922; Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 49, 1926. Miocene: Empire formation of Coos Bay, Oregon (Dall, 1909; Arnold and Hannibal, 1913; Howe, 1922); Wildcat formation, Humboldt County (Martin), perhaps Pliocene. Pliocene: Jacalitos and Etchegoin formations of Coalinga district (Arnold) ; Purisima and Merced formations of the San Francisco coastal region and near Sargent (Martin; ^"^nold and Hannibal); "Fernando" of Fugler's Point, Santa Barbara County (Carson). Pliocene or Pleistocene: Coos conglomerate ? (Howe). This species resembles L. corbis, but has fewer and more rounded ribs becoming dis- tinctly flattened toward the outer border. The beaks are curved and point forward as in corbis. Laevicardium (Cerastodenna) ciliatum (Fabricius) Plate 19, Figure 11 Cardium ciliatum Fabricius, Fauna Gronl., p. 410, 1780; Reeve, Last of the Arctic Voyages (Belcher), Vol. 2, p. 398) 1855; Sars, Fauna Reg. Arct. Norv., p. 46, pi. 5, figs, ia-b, 1878; Dall, Wash. Acad. Sci., Alaska., Res. Harri- man Alaska Exped., Vol. 4, pp. 113, 121, 1904, reissued by the Smithsonian Institution, 1910; Dall, in Moffit, U. S. Geol. Surv., Bull. 533, p. 46, 1913; Dall, Canadian Arctic Exped., Vol. 8, Pt. A, p. 26A, 1919; Jour. Wash. Acad. Sci., Vol. 9, p. 2, 1919. Cardium (Cerastoderma) ciliatum Fabricius, Dall, U. S. Nat. Mus., Bull. 112, p. 39, 1921; 1. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 142, pi. 19, figs. 8, 8a, 1924. ? Miocene: "Miocene" of Popof Island, Alaska (Dall, 1904). Pliocene: "Pliocene" near Nome, in the old beaches; Otter Creek; Center Creek, all in Alaska (Dall, 1913); "late Pliocene" of St. George Island and St. Paul Island, Pribilof group (Dall, 1919). Pleistocene: Pleistocene of Arctic Sound; east side of Coppermine River; south side of Bernard Harbor, Northwest Territories (Dall, 1919); Douglas Island, Juneau Harbor, Alaska (Dall, 1910). Recent: Arctic Ocean and southward to Puget Sound and northern Japan; also circumboreal (Dall, 1921). Lcevicardium ciliatum has a rather thin, brittle shell. It is somewhat like L. decor- aium, but has triangular ribs. Cardium islandicum Chemnitz, 1782; C. edule Mohr, 1786, not of Linnseus, 1758; C. pubescens Couthouj', 1838; C. arcticum Sowerby, 1840; C. dawsoni Stimpson, 1862, and hayesii Stimpson, 1863; and C. boreale Broderip and Sowerby, 1829, not of Reeve, 1844, are probably synonyms of L. ciliatum (Fabricius), as suggested by Dall (1901). Subgenus NEMOCARDIUM Meek, 1876 Nemocardium Meek, U. S. Geol. Surv. Territories, Vol. 9, p. 167, 1876; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1078, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 385, 1901; Woodring, Carnegie Inst., Publ. No. 366, p. 146, 1925. Type (by monotypy), Cardium semi-asperum Deshayes; figured by Cossmann and Pissarro, Icon. Coq. Eoc. Env. Paris, pi. 19, figs. 72-7, 1904-6; Paris Basin Eocene. Shell comparatively small, with fine ribs, the ribs of different character on the posterior jiart of the shell, being spinose, tuberculate, or cancellate, instead of simple. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 311 Laevicardium (Nemocardium) centifilosum (Carpenter) Plate 19, Figures 9, 10 Cardium var. centifilosum Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 642, 1864. Cardium centifilosum Carpenter, Gabb, Geol. Surv. Calif., Palao., Vol. 2, p. 99, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 232, 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 189, 1892. Prolocardia centifilosa Carpenter, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1113, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 391, 1901; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 142, 1903; English, Univ. Calif, Publ. Geol., Vol. 8, p. 210, 1914; Dall, U. S. Nat. Mus., Bull. 112, p. 40, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 146, pi. 34, figs. 2a-d, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 6.5, .Art. 22, p. 6, 1925. Type locality: Monterey, California; Recent. ? Miocene: Sunol, Alameda County (Cooper). Pliocene: Lower Fernando of Pico Canyon, Los Angeles County (English) ; San Diego well, Balboa Park, San Diego (Dall); Southern California Gas Company's weU No. 1-4, Sec. 4, T. 28 S., R. 23 E., Kern County, upper Etchegoin, si-xteen specimens (H. R. Gale) ; Packard's Hill, and Bath-house Beach, Santa Barbara (Arnold). Pleistocene: "Pliocene" of Deadman Island and Timm's Point, "not uncommon;" lower San Pedro of Dead- man Island "rare" (Arnold) ; lower San Pedro fauna of Nob Hill cut, San Pedro, three valves (T. S. Oldroyd). Recent: Bodega Bay, California, to Lower California, Mexico (DaU, 1921). This species is small, orbicular, and ventricose, with numerous, small, closely- spaced, radiating riblets, the posterior portion of the valves having also concentric sculp- ture. It differs from L. substriahwi in its stronger ribbing, in its posterior cancellate sculpture, and in its orbicular shape. L. substriatum is sUghtly elongated at the posterior ventral portion, and the radial sculpture is very low and inconspicuous. L. centifilosum has commonly been classified in the genus or subgenus Prolocardia Beyrich; but as ex- plained below, this classification is now believed to be erroneous. Genus PAPYRIDEA Swainson, 1840 Papyridea Swainson, Treat. Malac, p. 374, 1840; Gray, Proc. Zool. Soc. London, Pt. 15, p. 185, 1847; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 208, 1871; DaU, Trans. Wagner Inst. Sci., Vol. 3, p. 1075, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 384, 1901. Type (by subsequent designation, Gray, 1847), Cardium soleniforvie Bruguiere, 1789, = C. spinosum Meuschen, Mus. Gever., p. 442, 1787. Valves elongate-oval, gaping, moderately ventricose or flattened, posterior portion of shell longer than anterior; ribs numerous, narrow, often spiny. This group is distinguished by being markedly inequilateral. Papyridea spinosa (Meuschen) variety aspersa (Sowerby) Cardium aspersum G. B. Sowerby, Proc. Zool. Soc. London, Pt. 1, p. So, Sept., 1833; Conch. Illust., Cardium, fig. 15, 1834; Carpenter, Brit. .\ssn. Adv. Sci., Rept. for 1856, p. 364, 1857; Romer, Martini und Chemnitz Conch. Cab., Ed. 2, Cardium, p. 76, 1869, as "asperum." Cardium bullatum. Lamarck, var. /3, Reeve, Conch. Icon., Vol. 2, Cardium, as a variety of fig. 8, pi. 2, 1844. Cordiwra (Popyridea) aspersttra Sowerby, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 150, 1894; Dall, Vol. 37, p. 265, 1909. Cardium variegatum Mabille, Bull. Soc. Philomathique de Paris, Ser. 8, Vol. 7, p. 75, 1895, not of Sowerby, 1840. Cardium (Papyridea) spinosum Meuschen, var. aspersum Sowerby, DaU, Trans. Wagner Inst. Sci., Vol. 3, p. 1108, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 391, 1901; Lamy, Journ. de Conchyl., Vol. 57, p. 234, 1909. Pleistocene: Oaxaca, Mexico (coUected by R. H. Palmer). Recent: Magdalena Bay, Lower California, Mexico, south to Guayaquil (Dall, 1909). Papyridea spinosa (Meuschen) is an Atlantic shell. The Pacific variety aspersa is supposed to have less posterior elongation and flatter ribs. 312 San Diego Society of Natural History [Memoirs Genus FRAGUM Bolten, 1798 Fragum Bolten, Mus. Boltenianum, p. 189, 1798; Morch, Cat. Conch. Yoldi, Pt. 2, p. 35, 1853; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 210, 1871; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1074, 1075, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 384, 1901. Isocardia Oken, Lehrb. Naturg., Vol. 3, p. 234, 1815, in part, not of Lamarck, 1799. Hemicardium Swainson, Treat. Malac, p. 373, 1840. Loxocardium Cossmann, Cat. Illust., p. 160, 1887. Americardia Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 267, 1930, type Cardium medium Linnaeus. Type (by absolute tautonymy), Cardium fragum Linnseus; Indo-Pacific, Recent; figured by Reeve, Conch. Icon., Vol. 2, Cardium, pi. 4, fig. 23, 1844. Shell subtruncate behind, inflated, with strong ribs, no lunule or escutcheon, the channels simple, hinge normal, pallial line nearer the basal margin than in most Cardia. (Dall, 1900.) Fragum fragum is closely related to F. unedo (Linnseus), usually cited as the type. Section Fragum, s. s. Valves obtusely angular m front of the truncation ; ribs numerous, strong, pustular, or imbricate throughout. (Dall, 1900.) Fragum biangulatum (Broderip and Sowerby) Cardium biangulatum Broderip and Sowerby, Zool. Journ., Vol. 4, p. 367, January, 1829; Sowerby, Conch. Illust., Cardium, fig. 2, 1834 (date ?); Reeve, Conch. Icon., Vol. 2, Cardium, pi. 6, fig. 29, 1844; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 307, 1857; Romer, in Martini und Chemnitz, Conch. Cab., Ed. 2, Cardiacea, p. 104, pi. 14, figs. 12, 13, 1869; Dall, Nautilus, Vol. 32, p. 24, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Hanna and Hertlein, Vol. 16, p. 140, 1927. Cardium {Fragum) biangulatum Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 390, 1901; Lamy, Journ. Conch., Vol. 57, p. 234, 1909; Dall, U. S. Nat. Mus., Bull. 112, p. 39, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 144, 1924. Type specimen: In the British Museum, jide Oldroyd. Type locality: St. Elena and Isle of Plata, W. Colombia, fide Oldroyd. Pliocene: Coronados and Carmen islands, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary of Magdalena Bay, west coast of Lower California (Dall, 1918; Jordan, 1924) ; upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: San Pedro, California, south to Colombia. This species is characterized by its concavely truncated posterior end, with a pro- duced posterior margin. It has about twenty-eight prominent ribs. Fragum magnificum (Deshayes in Carpenter) Cardium 'planicoslatum Sowerby, Conch. lUust., Cardium, No. 83, pi. 50, fig. 25, 1834, not C. planicostatum Sedgwick and Murchison, 1829. Cardium magnificum Deshayes, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 187, 1857. Cardium (Fragum) magnificum (Deshayes MS.) in Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 265, 1901. Cardium (Fragum) magnificum Deshayes, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 265, 1909. Pleistocene: Coast of Oaxaca, Mexico (collected by R. H. Palmer). Recent: Lower California, Mexico, to Paita, Peru (Dall, 1909). This species is of the same character as F. biangulatum, which Carpenter considered a synonym, but it is proportionately higher and has fewer, broader ribs. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 313 Section Trigoniocardia Dall, 1900 Tngmiocardia DaU, Trans. Wagner Inst. Sci., Vol. 3, p. 1075, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 384, 1901. Type (by original designation), Cardium graniferum Sowerby. Shell small, few ribbed, medial rilis very strong; posterior end subtruncate with smaller, closer ribs; chaimels stronglj' concentrically sculptured; shell colorless, periostracum smooth. (Dall.) Fragum graniferum (Broderip and Sowerby) Cardium graniferum Broderip and Sowerby, Zool. Journ., Vol. 4, p. 367, January, 1829; Sowerby, Conch. Illust., Cardium, p. 3, No. 38, pi. 49, fig. 17, 1834; Reeve, Conch. Icon., Vol. 2, Cardium, pi. 8, fig. 43, 1844; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1075, 1900; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924. Cardium (Trigoniocardia) graniferum Broderip and Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 390, 1901 ; Vol. 37, p. 265, 1909. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Gulf of California, Mexico, south to Guayaquil (Dall, 1909). This is a small species with few imbricated ribs. Genus RINGICARDIUM Fischer, 1887 Ringicardium Fischer, Man. Conchyl., p. 1037, 1887; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1073, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 384, 1901. Type (by monotypy), Cardium ringens Chemnitz, = Cardium ringens Gmelin; Africa, Recent; figured in Reeve, Conch. Icon., Vol. 2, Cardium, pi. 1, fig. 6, 1844. Shell rotund, gaping, with flat ribs and chamiels, the posterior area with granulose channels; posterior margin sharply spinose, the spines crossing each other over the gape; left cardinals when interlocked posterior to the right ones. (Dall.) Apparently Ringicardium does not apply, to the west American species procerum, for which Stewart has erected the new subgenus Mexicardia. R. ringens is smaller, more quadrate in shape, has a shghtly straighter hinge line and quite different cardinal teeth. The cardinals of the left valve form a horse-shoe, curving completely around the chief cardinal of the right valve, whereas in procerum, as in the other west American subgenera of Loevicardium, the chief cardinals (one in each valve) are simple prongs, fitting side by side, and are practically the same in the left valve as in the right. Ringicardium is prob- ably more closely related to the true Cardium or to Fragum than to Lcevicardium. Genus SERRIPES Beck in Gould, 1841 Aphrodite Lea, Trans. Amer. Philos. Soc, N. S., Vol. 5, p. Ill, 1834, only species A. columba Lea; not Aphrodite Hiibner, 1816. ? Adacna Eichwald, p. 169, 1838 (see remarks on Landcardium) . Acardo Swainson, Treat. Malac, p. 374, 1840; not Acardo Bruguiere, 1789, nor Lamarck, 1799. Serripes (Beck MS.) Gould, Invert. Mass., p. 93, 1841; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, pp. 209-210, 1871; DaU, Trans. Wagner Inst. Sci., Vol. 3, p. 1077, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 384, 1901. Type (by monotypy), Cardium gronlandicum Gmelin. Valves smooth mesially, radially striate toward the ends; cardinal teeth obsolete; pallial line truncate behind; foot geniculate, compressed, serrate on the edge below. (Dall, 1900.) This boreal genus is readily distinguished by its lack of cardinal teeth. In discussing Cardium gronlandicum Gmelin, Gould remarks: "Dr. Loven informs me, that Beck has 314 San Diego Society of Natural History [Memoirs instituted a new genus for it which he calls Serripes, on account of the serrated margin of the foot." We have been unable to locate any earlier use of Serripes than that of Gould, which would make C gronlandicum the monotype. Stoliczka later (1871) gave this species as the genei'ic type. Serripes gronlandicus (Bruguiere) Cardium groenlandicum Chemnitz, Neues Syst. Conch. Cab., Vol. 6, p. 202, pi. 19, fig. 198, 1782; Bruguiere, Encycl. M^th. Vers, Vol. 1, pt. 1, p. 222, 1789; Gmelin, in Linnseus, Syst. Nat., Ed. 13, p. 3252, 1792; Gould, Invert. Mass., p. 93, 1841; Moller, Index Moll. Groenl., p. 20, 1842. Cardium horeale Reeve, Conch. Icon., Vol. 2, Cardium, pi. 22, fig. 131, 1845, not of Broderip and Sowerby, 1829. Cardium (Serripes) groenlandicum Chemnitz, Dall, E.xped. to Point Barrow, p. 183, 1885. Serripes gronlandicus "Beck," Dall, 17th Ann. Rept., U. S. Geol. Surv., Pt. 1, p. 844, 1896; Dall, in Spurr, 20th ,\nn. Rept., Pt. 7, p. 174, 1900. Serripes gronlandicus Gmelin, DaD, Washington Acad. Sci., .Alaska, Repts. Harriman Alaska Exped., Vol. 4, pp. 114, 121, 1904; reissued by the Smithsonian Inst., 1910; Dall, in Moffit, U. S. Geol. Surv., Bull. 533, p. 46, 1913 (author's name omitted); Dall, Canadian Arctic Exped., Vol. 8, Pt. A, p. 28A, 1919; U. S. Nat. Mus., Bull. 112, p. 40, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 145, pi. 8, fig. 3, 1924. Type locality: Coast of Greenland. ? Miocene: St. Paul Island, Nushagak, Unga Island, Kadiak Island, Alaska, also British Columbia (Dall, 1896, 1900, 1904).! Pliocene: About one-fourth mile west of Snake River; also second beach one and a half miles east of Nome, Alaska (Dall, in Moffit, 1913). Pleistocene: Arctic Sound, Northwest Territories; also south side of Bernard Harbor (Dall, 1919); St. Paul Island, Bering Sea; Douglas Island, Juneau Harbor, Alaska (DaU, 1910); also Quebec, etc., fide DaU, 1900. Recent: Arctic seas and south to Hakodate, Japan, and to Puget Sound; also circumboreal (Dall, 1921). This species has been attributed to Gmelin and to Beck. Chemnitz appears to have been first to describe it, and Bruguiere used the name in a strictly binomial manner three years prior to Gmelin's use of it. Most of the synonymy has been omitted in the above tabulation. Serripes laperousii Deshayes is edentulous (when mature), but noticeably larger. Serripes laperousii (Deshayes) Cardium laperousii Deshayes, R6vue Zool. Soc. Cuv., p. 360, 1839; Mag. Zool., pi. 48, 1841. Cardium (f Serripes) laperousii Dall, .Amer. Journ. Conch., Vol. 7, p. 148, 1871. Serripes laperousii Deshayes, Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1112, 1113, 1900; Proc. IT. S. Nat. Mus., Vol. 23, p. 391, 1901; Bull. 112, U. S. Nat. Mus., p. 40, 1921; I. S. Oldroyd, .Stanford Univ. Publ. Geol., Vol. 1, p. 145, 1924. Pleistocene: "Pleistocene of the .Aleutian Islands and of the boulder clay of southeastern Alaska near Juneau." (Dall, 1900). Recent: Bering Strait to Hakodate, Japan, and Sitka, Alaska (Dall, 1921). Genus PROTOCARDIA Beyrich, 1845 Protocardia Beyrich, Zeitsehr. f. Malak., p. 18, Feb., 1845, Cardium hillanum Sowerby included; Herrmannsen, Ind. Gen. Malac, Vol. 2, p. 336, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1078, 1900; Proc. U. S. Nat. Mus,, Vol. 23, p. 385, 1901; Woodring, Carnegie Inst., Publ. No. 366, p. 146, 1925. "Protocardium" Beyrich, Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 209, 1871. > Grewingk also reported this species from the Miocene of Alaska, and some of Dall's reports at least are probably based on Grewingk. Eichwald, however, p. 131. 1871, attributed Grewingk's specimens to the Cretaceous and renamed them Venus provida. See the note to Mya arenaria variety profundior, p. 414. These beds, associated with volcanic tuffs, have been called Miocene so many times, it seems hardly possible they could be Cretaceous. Volume 1 1 PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 315 Type (by subsequent designation, Herrmannsen, 1847), Cardium hillanum Sowerby, Mill. Conch. Gt. Brit., Vol. 1, p. 41, pi. 14, upper figure, 1813; Cretaceous of England; also figured by Stoliczka, Mem. Geol. Siu-v. India, Vol. .3, pi. 12, figs. 8-10, 1871. Shell globose, inflated, closed; sculpture of concentric striations or riblets, except on posterior area which has radial ribs ; lunule and escutcheon lacking. The Cretaceous species of Protocardia are so different from Lcevicardium centifilosum (Carpenter) that it seems unnatural to group the latter in the same genus with them. Typically, Protocardia has concentric sculpture except on the posterior area, which is radially sculptured. L. centifilosum has radial sculpture on the anterior two-thirds or three-quarters of the shell. The distribution of the two kinds of sculpture is therefore just the reverse. The Cretaceous Protocardice have a heavy hinge with stout laterals, quite unlike the hinge of the California Recent L. centifilosum. These differences are sufficient to remove the California Recent species from Beyrich's genus. Superfamily Veneracea Family VENERIDAE Shell of trigonal, circular, quadrate, or elongate-quadrate shape, usually heavy, equivalved, with prosogyrous beaks and external resilium embraced by the ligament; surface sometimes smooth and polished, more often sculptured with irregular growth lines, distant concentric grooves, or elevated lamellae, with or without radial striations or riblets ; a shield-shaped area in front of the beaks called the lunule and a lunate area behind the beaks called the escutcheon sometimes marked off by a sharp border and characterized by different sculpture ; hinge with two to four, strong, often bifid cardinals in each valve and occasionally an anterior lateral in the left valve, the normal arrangement of the teeth sometimes modified in various ways; pallial sinus usually distinct. Geologic range: Cretaceous to Recent. Distribution: World wide. Various classifications of this very important family have been attempted, perhaps the best known of which is that advocated by Dall.' Ball's classification has recently been more clearly elucidated and illustrated by Palmer.'- However, in some respects this classi- fication is artificial and misleading, and it is not improbable that the radically different classifications proposed by Jukes-Browne,^ Cossmann,'' and other Europeans are equally as good. Neither Dall nor the Europeans have adhered strictly to the rules of nomencla- ture as now understood, and, as a consequence, a certain amount of nomenclatorial re- vision must be undertaken. = In this respect a recent article by Marwick" on the New Zealand VeneridcB is helpful. It is unfortunate that the terms lunule and escutcheon are commonly used in a sense almost the reverse of their derived meanings, and it is to be hoped that before long suit- able substitutes will be found. ^ "Synopsis of the Family Veneridte and of the North American Recent Species." Proc. U. S. Nat. Mus., Vol. 26. pp. 335-412, pis. 12-16. December 29, 1902; Trans. Wagner Inst. Sci., Vol. 3, pp. 1219-1334, October, 1903. * Katherine Van Winkle Palmer, Palaeontographica Americana, Vol. 1, no. 5, pp. 209-522, March, 1927; pis., 1929. " Proc. Malac. Soc. London, Vol. 8, pp. 148-177, pi, 6, 1908; pp. 233-246, 1909; Vol. 10. pp. 36-38. 1912; pp. 95-104, 1912; Vol. 11, pp. 58-94, 1914. < Ann. Soc. Roy. Malac. Belg., Vols. 21, 22, 1886-7. ^ Pressure of other work has limited the time which the present authors could devote to this family. \ careful discussion of the Cali- fornia Pliocene and Pleistocene Veneridx must await a more propitious occasion. « Trans. New Zealand Inst., Vol. 57, pp. 567-635. pis. 34-54, Feb., 1927. 316 San Diego Society of Natural History [Memoirs Genus VENUS Linnaeus, 1758 Venus Linnaeus, Syst. Nat., Ed. 10, p. 684, 1758; Children, Quart. Journ. Sci., Lit., Arts., Vol. 14, p. 314, 1823; Gray, Proc. Zool. Soc. London for 1847, p. 183, 1847, type V. verrucosa Linnaeus. Type (by subsequent designation, Gray, 1847), Venus verrucosa Linnaeus, op. cit., p. 685, 1758; figured by Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 135, pi. 10, fig. 3 (hinge), 1817; Reeve, Conch. Icon., Vol. 14, pi. 12, figs. 40a, 406, 1863; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 368, pi. 57, figs. 1-6, 1893; Recent along the coasts of England and southern Europe to Africa, also Mediterranean; Pliocene of Europe; Pleistocene of England; etc. Shell moderately large and heayy, of a rounded subtrigonal outline, sculptured with concentric striae or growth lines and sometimes raised lamellae and radial striations or riblets, escutcheon and lunule both defined; hinge rather heavy and broad, with a posterior smooth or roughened platform- hke area of variable width behind the teeth, when narrow this area compressed into a long ill-defined ridge, but when wide Ijordered on the anterior edge by a tooth-like ridge set off by a groove, anterior to the platform-like area in the left valve two cardinal teeth, the posterior of which is bifid, and a more or less developed anterior pustule (occasionally the posterior ridge described above is suffi- ciently well defined to be called a tooth, m which case there are three cardinals), m. the right valve three cardinals in addition to the posterior ridge, the posterior and middle ones bemg bifid or tending to be so; pallial sinus distmct, short; inner margms of valves crenulated or fluted. Apparently the earliest valid type designation was that of Gray, who definitely selected Venus verrucosa as the type of the genus. Lamarck, in 1799,' used V. mercenaria as an example; but in 1801,' he used V. verrucosa as the example. Neither of these pas- sages can be construed as type designations; and to interpret them as such would lead to confusion.^ Subgenus ANTIGONA Schumacher, 1817 Cytherea Bolten, Mus. Boltenianum, p. 177, 1798; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 3.54, 1902; Trans. Wagner Inst. Sci., Vol. 3, pp. 1271, 1272, 1273, 1903; not Cytherea Fabricius, Ent. Syst., Vol. 4, p. 413, 1794, LHplera. Antigona Schumacher, Ess. Nouv. Syst. Habit. Vers Test., pp. 154, 155, pi. 14, fig. 2, 1817; Woodring, Carnegie Inst., Publ. No. 366, p. 1.56, 1925; Marw'ick, Trans. New Zealand Institute, Vol. 57, p. 598, 1927. Type (by monotypy), Antigona lamellaris Schumacher, op. cit., p. 155, pi. 14, fig. 2, 1817; Indo-Pacific, Recent.^ Shell similar to that of Chione, but with a small part of the anterior cardinal in the left valve separated off into a pseudolateral, and a corresponding pit in the right valve. Marwick (1927) has. shown^ that the anterior lateral tooth in the left valve of Antigona is not of the same origin as the anterior lateral in Dosinia, Pitar, MacrocaUista, Meretrix, etc., and that its classification with the latter is purely artificial. Antigona is more closely related to Venus and to Paphia. Venus (Antigona) multicostata Sowerby Venus multicostata Sowerby, Proc. Zool. Soc. London for 1835, p. 22, June, 1835; Thes. Conch., Vol. 2, p. 706, pi. 152, fig. 10, 1853; Reeve, Conch. Icon., Vol. 14, Venus, pi. 3, fig. 9, 1863; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 528, 569, 1864. Cytherea (Cytherea) multicostata Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 390, 1902. ' M«m. Soc. Hist. Nat. Paris, p. 84, 1799. « Syst. Anim. s. Vert., p. 123, 1801. ' Murray, Fund. Test., p. 148, pi. 3, figs. 11. 16. 17, 1771, is said to have given Venus dione Linnaeus as the sole example of the genus. We have not seen Murray's work. * Unfortunately, there is a complication over the type of Antigona. Schumacher identified his figure with Veiius cancellata Linna?us, which is the type of Chione; but as he referred to Chemnitz's conception of cancellata, it may be possible to avoid the loss of Antigona under Chione. 6 The left anterior lateral of MacrocaUista is the continuation of a low ridge proceeding from below the umbo, whereas the anterior lateral of Antigona is a prolongation of the front limb of the anterior triangular cardinal tooth. Ontogenetic studies by Marwick have proved the latter mode of development in Kuia vellicala (Hutton). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 317 Shell large, heavy, subovate, moderately ventricose, with small umbones and more or less roimded profile; sculptured with concentric, umbonally-re fleeted lamellae and occasionally with low, uniform, flattened ribs; lunule of moderate size, sharply delimited by a sinus, escutcheon of moderate size; right hinge with three cardinals, the middle and posterior heavy and lightly mesially grooved, left hinge with three cardmals, the posterior one an elongate ridge on the base of the nymph, and a small pseudo-lateral near the base of the strong front cardinal; pallial sinus small, rounded at the apex. Pleistocene: Coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Gulf of California, Mexico, south to Panama (Dall). This species is very different from Antigona fordi (Yates). Venus thouarsi Valen- ciennes is probably a synonym. A number of species assigned to Antigona have been reported from pre-Pliocene hori- zons in California, some of which appear to belong to other genera. Venus (Antigonaj fordii Yates Venus fordii Yates, Santa Barbara Soc. Nat. Hist., Bull. No. 2, p. 46, pi. 1, figs. 1-5, IS90. Cytherea (Ventricola) fordi Yates, Dall, Proc. U. S, Nat. Mus., Vol. 26, p. 390, 1902. Antigona fordi Yates, DaU, U. S. Nat. Mus., Bull. 112, p. 41, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 152, 1924. Shell heavy, subtrigonally ovate, strongly ventricose, with prominent, stronglj' curved beaks, wide, depressed lunule, and wide escutcheon delimited by racUal threads; sculptured by concentric striae superposed on concentric undulations, and radial riblets; huige of the right valve with three strong cardinal teeth, the middle one stoutest, hmge of the left valve with two cardinals, a posterior lamellar ridge beneath the ligament, and a small conical pseudo-lateral just anterior to the front car- dinal, fitting into a corresponding pit in the right hinge plate; pallial sinus small, angular. Type locality: Santa Barbara Channel, California. Pleistocene: San Pedro. Recent: Monterey, California, to Lower California; ? Panama (Dall, 1921). This species belongs to the group Ventricola Romer.' Its inflated, Isocardia-\ike appearance is very different from that of mxiUicostaia. Subgenus VENUS, s. s. Shell with strong concentric lamellae and secondary low radial imdulations or ribs arranged divaricately; hinge with a faint anterior pseudolateral in the left valve. Venus mercenaria Linnaeus has generally been considered the type of the genus Venus, but according to the International Rules the type must be Venus verrucosa. This changes Venus, sensu siricto, of most recent authors to Mercenaria Schumacher, which can now be considered a subgenus of Venus. The type of Chione is so similar to the type of Venus, represented by V. verrucosa, that it appears to be hardly more than sectionally distinct. The true Venus must be considered intermediate between Antigona and Chione, the anterior pustule being exceedingly faint and probably not of very great significance. Until typical Venus can be more closely allied to one or the other of these groups, it will probably be of little importance as a subgenus. Venus verrucosa has a relatively nar- rower and longer hinge plate than V. cancellata, which is a result of the more trigonal shape of the latter. It should be noted that the small, narrow anterior cardinal tooth of both is quite variable in strength. The sculpture patterns of V. verrucosa, the type of Ve7ius, and of V. cancellata, the type of Chione, illustrate the chief difference between these subdivisions of Venus, sensu ' Malakozool. Blatter, Bd. 14, p. 115, 1867, type by subsequent designation (Dall, 1902). Venus rugosa Gmelin (= V. rigida Dillwj-n); West Indies. Recent, fide Woodring, 1925. 318 San Diego Society of Natural History [ Memoirs lato. V. verrucosa has rather close-set concentric lamellae, which are each multiple, being generally' composed of about three appressed lamellar folds leaning in an umbonal di- rection, whereas V. caiicellata has distant, generally single, more erect, often sharp, con- centric lamellae or frills. In the umbonal region the sculpture, both radial and concentric, of these two types is approximately identical ; but during the growth of the shells the radial sculpture of the one becomes radically different in character from that of the other. In passing from the umbonal region to the ventral margin, the radial riblets must cover an increasing amount of area. On the valves of verrucosa this area is filled by the addition of fully-developed ribs along an axis of divarication, generally posterior to the medial axis, as well as by a constant increase in the width of the ribs ventrally. On cancellata the ribs divide into several parts as the area which they must cover increases, producing temporar- ily bunches or fascicles of riblets, which ultimately, with the growth of the shell, become a uniform series of equal ribs. The specimens of V. cancellata in the collections at Stanford University average smaller and flatter than those of verrucosa. Also the escutcheon of the former species is larger and the shell more trigonal, but these differences appear to be little more than specific. The right valves of some specimens show a slight prominence below the liga- ment, indicating the position of a possible fourth cardinal tooth. Clausina Brown, according to Dall's usage, 1903, is an exact synonym of the typical subgenus of Venus as here understood. Subgenus CHIONE Megerle von Miihlfeld, 1811 Chione Megerle von Miihlfeld, Gesellschaft Naturf. Freunde zu Berlin, Jahrg. .5, p. 51, 1811, fide Woodring, 1925; Gray, Proc. Zool. Soc. London for 1847, p. 183, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1286, 1287, 19C3; Woodrirg. Carnegie Inst., Publ. No. 366, p. 1.59, 1925. Type (by subsequent designation. Gray, 1847), Venus dysera Chemnitz = Venus cancellata Linnaeus, Syst. Nat., Ed. 12, p. 1191, 1767; West Indies, Recent. Shell like that of Venus, sensu strido, but with ribs increasing by division, not by divarication along an axis, and with ccncentric sculpture of more distant lamellae appearing as erect frills; hinge generally heavier, the left valve mthout the anterior pustule; escutcheon larger. Venus (Chione) gnidia Broderip and Sowerby Plate 16, Figures 5a, 56 Venus gnidia Broderip and Sowerby, Zool. Journ., Vol. 4, p. 364, January, 1829; Sowerby, Gen. Rec. MoU., Pt. 41, pi. 251, fig. 7, 1834; Gray, Zool. Beechey's Voy., MoU., p. 151, pi. 41, fig. 3, 1839; Sowerby, Thes. Conch., Vol. 2, p. 709, pi. 154, fig. 25, 1853; Reeve, Conch. Icon., Vol. 14, Venus, pi. 11, fig. 37, 1863; Carpenter, Brit. Assn Adv. Sci., Rept. for 1863, p. 561, 1864. Venns {Chione) gnidia Broderip and Sowerby, Carpenter, Cat. Reigen CoU. Mazat. Moll. Brit. Mus., p. 71, 1857 Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 147, pi. 14, fig. 7, 1903; Lamy, Journ. Conchyl., Vol. 57, p. 245, 1909 Chione gnidia Broderij] and Sowerby, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 153, 1894; Dall, Vol. 26, p. 394, 1903 McLaughlin and Waring, Calif. State Mining Bure.au, Bull. 69, Map Folio, pi. 1, fig. 52, 1914; Jordan, Bull So. Calif. Acad. Sci., Vol. 23, p. 151, 1924; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 253, 1929 Shell large, hea\y, of a subtrigonal shape, posterior dorsal margin broadly curving to a rather acutely rounded posterior ventral extremity, immediately below which the ventral margin is slightly indented, anterior dorsal margm concave, moderately curving, turning abruptly into the strongly convex anterior curve; sculpture of distant, high, concentric frills and prominent radial riblets; hinge normal, the posterior area somewhat restricted, the bifurcation of the middle left cardinal an- terior to the middle of tlie tooth, the anterior right cardinal well separated from the shell margin. Size up to 114 mm. in height, and 120 mm. in length. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 319 Pleistocene: "Rare in the upper San Pedro series of San Pedro" (Arnold); Pleistocene of Signal Hill (in Old- royd Collection at Stanford L^niversity; McLaughlin and Waring); Clark's well, near Encinitas, San Diego Count}' (Mrs. Kate Stephens, MS.); northeast shore of Mi-ssion Bay, San Diego County (Frank Stephens); upper Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Cedros Island, Lower California, Mexico, to Paita, Peru. The geologic history of this well-characterized species is not yet fully understood. It is very closely related to V. elsmerensis, from which it is distinguished by its more ab- ruptly truncated anterior extremity and by the details of the hinge. Weathering usually disguises the sculpturing of T'. elsmerensis. It is also similar to V. temblorensis of the California Miocene, but this latter species and a Recent species in the Gulf of California have more acute posterior extremities. Venus richthofeni (Hertlein and Jordan),' from the Miocene of Lower California, much resembles the young of gnidia. It may be the same as the Recent Gulf species, which would give the latter a range of Miocene to Recent. The occurrence of T'. gnidia in some of the Pleistocene faunas of California helps to show that temperatures warmer than the present prevailed at times during the Pleisto- cene. Venus i'Chione) elsmerensis (English) Plate 16, r'igures 60, 6b, 7 ? "Chione gnidia Sowerby," Watts, Calif. State Mining Bureau, Bull. No. 3, p. 34, 1S94. Chione elsmerensis English, Univ. Calif. Publ. Geol., Vol. 8, p. 214, pi. 23, figs, la, lb, 1914; Nomland, Vol. 9, p. 202, pi. 9, figs. 3a, 3b, pi. 10, fig. 1, 1916; Vol. 10, p. 218, 1917. ? "Chione pabloensis f", Clark, Univ. Calif. Publ. Geol., Vol. 8, pi. 58, fig. 1. 1915. Shell like that of Venus gnidia but with a longer and more roimded anterior extremity, a narrower posterior right cardinal, a more symmetrically bifurcated middle left cardinal, and possibly coarser radial sculpture. Type STpecimen : In the University of California collection. Type locality: Elsmere Canyon, Los Angeles County; Univ. Calif, locality 1735; lower Pliocene. ? IJ. Miocene: Specimen from the San Pablo formation questionably identified as pabloensis by Clark. Pliocene: Lower Pliocene of Elsmere Canyon, Los Angeles County (English); common in Chione elsmerensis zone, lower Pliocene, Coalinga district, California (Nomland, 1917); ? near Tar Canyon, Kings County (as gnidia, Watts). This species is somewhat intermediate between V. gnidia and V. securis. It is dis- tinguishable from the latter by its higher and more central beaks with more extended anterior, and probably also by its hinge. The details of the hinge vary considerably in different individuals. Venus (Chione) temblorensis Anderson Venus (Chione) temblorensis Anderson, Proc. Calif. Acad. Sci., Ser. 3 (Geol.), Vol. 2, p. 196, pi. 14, figs. 36-38, 1905; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 542, pi. 43, figs. 1, la, 1907, figures reproduced in U. S. Geol. Surv., Bull. :5C9, pi. 30, figs. 1, lo, 1907; probably not "Venus {Chione) temblorensis (Anderson)," Reagan, Trans. • Kansas Acad. Sci., Vol. 22, p. 182, 1909, fide Dall, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 307, 1922, which may be Venus securis Shumard. Type specimen : Formerly at the California Academy of Sciences, but lost in the San Francisco earthquake. Type locality: "Lower Miocene beds of Kern River and Temblor." ' Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 619, pi. 17, figs. 4, 7, 8, 1927. 320 San Diego Society of Natural History [ Memmhs Miocene: "Lower Miocene beds of Kern River and Temblor" (Anderson); head of Topanga Canyon, Los Angeles County [Temblor formation], (Arnold). The shape of this species, as figured, resembles Venus darwini Dunker of the Gulf of CaUfornia Recent fauna. They both belong to the gnidia clan. V. temblorensis may be the ancestor of securis Shumard. Venus (Chione) securis Shumard Plate 17, Figure 1 Venus securis Shumard, Trans. St. Louis Acad. Sci., Vol. 1, p. 122, 1858; Arnold and Hannibal, Trans. Amer. Philos. Soc, Vol. 52, pp. 590, 593, 594, 1913. Chione securis Shumard, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 120, pi. 11, fig. 8, pi. 13, figs. 2, 8, 9, April 2, 1909; Arnold, U. S. Geol. Surv., Bull. 396, p. 136, pi. 15, fig. 2, January 15, 1910; Arnold and Anderson, Bull. 398, p. 108, pi. 37, same figure, 1910; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916; Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 239, 245, 1916; Howe, Vol. 14, p. 92, 1922; Dall, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 307, 1922. Shell of medium size, elongate-trigonal, the posterior dorsal margin long and but slightly curved, at the extremity curving abruptly into the strongly convex ventral margm, anterior extremity short, the anterior dorsal margin descending abruptly and partly concavely from the beaks; sculpture similar to that of V. gnidia but weathered into various aspects; hinge similar to that of gnidia. Variety securis, s. s. Valves relatively compressed. Miocene: Montesano formation, middle Miocene of western Washington (Weaver) ; Empire formation of Coos Bay, Oregon (Arnold and Hannibal; Dall; Howe). Pliocene: Upper Wildcat formation, Humboldt County, California (Martin) ; Merced and Purisima formations of middle California (Arnold and Hannibal); Etchegoin formation of Coalinga region (Arnold; Martin); Etchegoin of Sargent oil field (Martin). Venus (Chione) securis Shumard variety ensifera Dall Plate 17, Figures 2a, 26, 3 Venus lamellifera Conrad, Geol. U. S. Expl. Exped., p. 724, Atlas, pi. 17, figs. 12, 12a, 1849; Amer. Journ. Conch., Vol. 1, p. 152, 1865; not F. lameUifera Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 251, pi. 19, fig. 19, 1837. Venus ensifera Dall, U. S. Geol. Surv., Prof. Paper 59, p. 122, 1909, new name for lamellifera. Venus parapodema Dall, op. cit., p. 122, pi. 11, fig. 11, pi. 13, fig. 1, 1909. Venus {Chione ?) clallamensis Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 183, pi. 1, fig. 13, Nov., 1909. Shell like that of the typical variety but more ventricose. Type specimens: In the U. S. National Museum. Type localities: Of V. ensifera Dall, Astoria, Oregon, Miocene; of V. parapodema, Coos Bay, Miocene; of clallamensis, East Clallam, Washington, Miocene. Miocene: Middle and upper Miocene of Oregon and Washington. This variety occurs with and intergrades with the typical variety, the intergrades being more common than the extremes. An examination of a series of specimens shows that the manner of weathering is the cause of different appearances which are not due to differences in the characteristics of the shells. It is strange that Dall took no account of this factor. More specimens may show that Venus pabloensis (Clark), from the upper Miocene of middle California, is another synonym. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 321 Venus (Chione) securis Shumard variety femandoensis (English) Plate 17, Figures 4a, 46, 5, 6 Chione new species, Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 526, 1907. Chione femandoensis English, Univ. Calif. Publ. Geol., Vol. 8, p. 215, pi. 23, figs. 9a, 96, 1914; Nomland, Vol. 10, p. 218, 1917; Waterfall, Vol. 18, pp. 78, 79, 1929. Shell like that of the variety ensifera, but smaller, with more sharply defined lunule and es- cutcheon. Type specimen: In the University of California collection. Type locality: Elsmere Canyon, Los Angeles County, lower Pliocene. Pliocene: Lower Pliocene of Elsmere, Holser, and Pico canyons, Los Angeles County (English, p. 209); S. D. S. N. H. localities 206 and 209, lower Pliocene of Elsmere Canyon, and loc. 2176, middle Plio- cene of Holser Canyon (H. R. Gale); Pico formation near Ventura (Waterfall). ? Pleistocene: "Saugus" formation near Ventura (Waterfall), this occurrence questioned by the present writers. It is not unlikely that the differences between this variety and the variety ensifera are due entirely to the state of preservation. Hitherto this form has been known from small or stunted individuals such as are shown in figures 5 and 6, but the specimen shown in figures 4a and 4b is unquestionably the same and indicates the more normal aspect of this variety. From the "lower series at East Clallam," Washington, probably Oligocene, Reagan' described a Venus (Chione ?) oJympidce from a single cast. Years later, in examining the specimen, Dall- assigned it to Antigona, and remarked that the "few particles remaining of the external layer of the shell indicate a finely reticulate sculpture." The specimen should be compared with a similar poor cast of Venus mediostriata (Clark) ^ of the basal Agasoma gravidum beds of middle California. Venus (Chione) securis Shumard variety semiplicata (Nomland) Chione semiplicata Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 305-6, pi. 15, figs. 2a, 26, 2c, November 8, 1917. Type specimen: In the University of California collection. No. 11,318. Type locality: About nine miles northeast of Coalinga, upper Miocene. Miocene: Santa Margarita formation at the type locality, about nine miles northeast of Coalinga, California. This variety is characterized by the gently and broadly rounded posterior extremity. It is of low convexity like the typical variety. Venus (Chione) succincta Valenciennes Plate 16, Figures la, 16, 2o, 26, 3, 4 Venus succincta Valenciennes, in Humboldt and Bonpland, Rec. Obs. Zool., Vol. 2, p. 219, pi. 48, figs, la-c, 1821; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 521, 641, 666, 1864. Venus californiensis Broderip, Proc. Zool. Soc. London for 1835, p. 43, June, 1835; Sowerby, Thes. Conch., Vol. 2, p. 711, pi. 154, figs. 40, 41, 1853; Reeve, Conch. Icon., Venus, Vol. 14, pi. 11, fig. 35, 1863. Venus leucodon Sowerby, Proc. Zool. Soc. London for 1835, p. 43, June, 1835. Venus undatella Sowerby, Proc, Zool. Soc. London for 1835, p. 22, June, 1835; Thes. Conch., Vol. 2, p. 711, pi. 153, fig. 22, 1853. ' Trans. Kansas Acad. Sci., Vol. 22, p. 182, pi. 1, fig. 12, 1909. ' Amer. Journ. ScL, Ser. 5, Vol. 4, p. 307, 1922. • Univ. Calif. Publ. Geol., Vol. 11, p. 150, pi. 5, figs. 5, 6, pi. 6, figs. 3, i, 1918. 322 San Diego Society of Natural History [ Memoirs Vemis califomiana Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 251, pi. 19, fig. 16, 1837. Verms mitlalli Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 250, pi. 19, fig. 15, 1837. Venus neglecia Sowerby, Zool. Beechey's Voy., Blossom, p. 151, pi. 41, fig. 8, 1839; Thes. Conch., Vol. 2, p. 710, pi. 154, fig, 39, 1853. Venvs entobapta Jonas, Zeitschr. f. Malakzool., p. 66, 1845. Venus simillima Sowerby, Thes. Conch., Vol. 2, p. 708, pi. 153, figs. 17, 18, 1853; Reeve, Conch. Icon., Vemis, Vol. 14, pi. 13, fig. 44, 1863. "Venus subrostrala Lamarck," Sowerby, Thes. Conch., Vol. 2, p. 710, pi. 154, fig. 39, 1853; Reeve, Conch. Icon., Vol. 14, Venus, pi. 14, figs. 54a, 54b, 1863; ? of Lamarck, 1818 ? (original reference not consulted). Venus excavata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 305, 351, 1857. Venus bilineata Reeve, Conch. Icon., Vol. 14, Venus, pi. 22, figs. 105a., 1056, 1863. Venus crassa Sloat MS., Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 566, 569, 1864, not V. crassa Quoy. Chione simillima Sowerby, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogi,st, p. 234, 1888. Chione succincia Valenciennes, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 94, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 234, 1888; Keep, West Coast Shells, p. 187, fig. 159, 1888, 1892; West .\merican SheUs, p. 70, fig. 56, 1904; Rev. Edition, p. 80, fig. 54, 1911; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 251, 1916; Dall, Nautilus, Vol. 32, p. 24, 1918; Weymouth, Calif. State Fish and Game Comm., Fish Bull. No. 4, pi. 9, fig. 3, 1920; Dall, V. S. Nat. Mus., Bull. 112, p. 42, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 154, 1924; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 148, 151, 1.52, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1924; Hanna and Hertlein, Vol. 16, p. 140, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Venus (Chione) suceincia Valenciennes, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 152, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 149, pi. 14, fig. 1, 1903; Lamy, Journ. Conchyl., Vol. 57, pp. 244, 245, 1909. Chione (Chione) succincia Valenciennes, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 392, 1902. Chione (Chione) undalella Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 392, 1902. Venus (Chione) simillima Sowerby, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 148, 1903. Chione undalella Sowerby, Dall, Nautilus, Vol. 32, p. 24, 1918; Weymouth, Calif. State Fish and Game Comm., Fish Bull. No. 4, pp. 12, 37, 67, pi. 9, fig. 2, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 42, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 154, pi. 55, fig. 2, 1924; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, pp. 560, 563, 1922; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 251, 255, 1929. Chione simillima Sowerby, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Shell of medium size, heavy, of varialile outline; sculi:)tured with strong concentric lamellae and radial ribs, the radial ribs often differentiated into stronger pairs separated by smaller single inter- calaries, but both concentric and radial sculpture variable in relative strength and disposition; teeth short and thick, seldom grooved, the anterior right cardinal small. Miocene: "Oregon; Martinez; San Pablo, Contra Costa County; Griswold's, San Benito County; Foxin's, Santa Barbara County; Santa Monica, Los Angeles County" (Cooper, as succincia; several of these records probably apply to some other species) . Pliocene: Middle Wildcat formation, Humboldt County (Martin); Seven Mile Beach, San Mateo County; San Fernando, Los Angeles County (Cooper); "Pico" formation near Ventura (Waterfall); Santa Antonita Point; Coronados Island; Carmen Island, Gulf of California, Mexico (Hanna and Hert- lein); upper conglomerate formation, Santa Rosalia district. Lower California, Mexico, one right valve (coll. by Marcel Touwaide). Pleistocene: Lower San Pedro series at Deadman Island, "rare" ; Barlow's Ranch, Ventura (Arnold) ; "Saugus" near Ventura (Waterfall); Pleistocene at Tomales Bay, Marin County (Dicker.son); Lower Quater- nary at Magdalena Bay, Lower California, Mexico (Dall, 1918; Jordan, 1924); upper San Pedro series (= Palos Verdes formation) at various localities in San Pedro and vicinity (Arnold; etc.); upper Pleistocene at foot of 26th Street, San Diego (Arnold; Stephens) ; northeast end of Point Loma (loc. 70) and two miles north of Del Mar (Stephens); about 5 miles east-northeast of Newport, in Orange County, loc. 97 (coll. by Wayne Loel); etc. Recent: San Pedro, California, south to northern Soutli .\merica. Venus (Chione) succincia Valenciennes is greatly over-supplied with names on account of the attractive and variable nature of the shell and the failure of authors to realize that a considerable degree of individual variation is a zoological feature well substantiated by proof in many well-known instances. Several specimens of this species all from the same locality are illustrated on plate 16 to show the variation of its shape and sculpture. The relative height of the shell and the frequency of the concentric lamel- Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 323 Ise are of little significance. These same variants are found nearly everywhere that the species occurs. The hinges are also somewhat variable. Weymouth (1920) figures two extreme variants, one known as undaiella, the other as succincta. His figures are exceptionally clear. Venus (Chione) fluctifraga Sowerby Venus fluctifraga Sowerby, Thes. Conch., Vol. 2, p. 712, pi. 154, figs. 42, 43, 1853. "Venus callosa Conrad" Sowerby, Thes. Conch., Vol. 2, p. 712, pi. 154, figs. 44, 45, 1853. ? Venus gibbosula Deshayes, Proc. Zool. Soc. London for 1853, p. 7, 1853, habitat unknown. "Vemts gibbosula Deshayes, MS.", Reeve, Conch. Icon., Vol. 14, Venus, pi. 13, fig. 47, 1863. Venus cortezi Sloat MS., Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 570, 1864. Chione fluctifraga Sowerby, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 234, 1888; Weymouth, Calif. State Fish and Game Comm., Fish Bull. No. 4, p. 37, pi. 9, fig. 1, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 42, 1921; Oldroyd, Stanford Univ. Publ. GeoL, Vol. 1, p. 1,53, pi. 39, fig. 3, 1924; E. K. Jordan, Bull. So. Calif. Acad. vSci., Vol. 23, p. 148, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. IS, p. 78, 1929. Chione (Chione) fluctifraga Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 392, 1902. Venus {Chione) fluclifraga Sowerby, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 147, pi. 14, fig. 2, 1903. Shell of medium size, hea\'y, outline varying from nearly orbicular to sulrtrigonal; sculptured with radial ribs and concentric cords somewhat midulose at their intersections, the posterior thuxl or less of the valves sculptured differently, with fewer but coarser radials and weaker or almost obso- lete concentric sculpture; hmge characters like those of succincta, but the anterior right cardinal tooth sometimes absent. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan); "Saugus" formation near Ventura (Waterfall); "rare in upper San Pedro series at San Pedro;" "common in the Pleisto- cene at Twenty-sixth Street, San Diego" (Arnold). Recent: San Pedro, California, to the Gulf of California, Mexico (Dall). This species is readily distinguished from succincta by the difference between the posterior sculpture and that of the other parts of the valve. Sowerby gave Australia as the habitat, which is probably an error. If fluctifraga came originally from AustraUa, the California species would have to take one of the later names. The sculpture aiul shape of this species are variable. Some specimens are somewhat oblique or trigonal while others are nearly orbicular in profile. Sowerby's figure of the interior of a right valve shows an unusually deep pallial sinus. There are a number of species belonging to Chione in the Miocene formations of California which cannot be discussed here. "Venus" pertenuis Gabb and martini Clark' of the Miocene belong to dementia. Section Lirophora Conrad, 1863 Lirophora Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, pp. 575, 586, 1863; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 358, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1288, 1903; Woodring, Carnegie Inst., Publ. No. 366, p. 162, 1925. Type (by subsequent designation, Ball, 1902), Venus athlefa (Conrad), = Venus latilirata Conrad, figured by Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1298, pi. 42, fig. 3, 1903; Miocene and Pliocene of the Atlantic coast. Sculpture of broad concentric waves, attenuated and often conspicuously lamellose di.stally; radially striate ; ligament not covered by the valve margins ; the edges of the right nymph and of the left posterior cardinal with interlocking rugosities. Venus (Chione) latilaminosa Anderson and Martin,- of the lower Miocene of Kern River, belongs to this section. The Recent species are confined to the tropics. ' Univ. Calif. Publ. Geol., Vol. 8, p. 470. pi. 54. fig. 1. 1915. ' Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, pp. 59-60, pi. 1. figs. 2a, 26, 2c, 1914. 324 San Diego Society of Natural History [Memoirs Venus (Chione) mariae d'Orbigny Venus maris: d'Orbigny, Voy. Amer. Muriel., Moll., p. 563, 1840. Venus cy-pria Sowerby, Thes. Conch., Vol. 2, p. 722, pi. 157, fig. 113, 1853; Reeve, Conch. Icon., Vol. 14, Venus, pi. 23, figs. 116a, 1166, 1863; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 571, 1864. Chione (Liro-phora) marix Orbigny, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 395, 1902. Chione manse d'Orbigny, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924. Shell rather small, trigonal, with high umbones and the posterior extremity prolonged; sculpture of large, reflected, concentric lamellse and fine radial wrinkles which may be obsolete on some speci- mens. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Gulf of California, Mexico, to Guayaquil, Ecuador. This is a handsome species resembling Venus paphia Linnaeus of the Caribbean region. Subgenus MERCENARIA Schumacher, 1817 Mercenaria Schumacher, Ess. Nouv. Syst. Habit. Vers Test., pp. 45, 135, pi. 10, fig. 3, 1817. Type (by monotypy), Mercenaria violacea Schumacher, op. cit., p. 135, pi. 10, fig. 3, 1817, = Venus mercenaria Linnseus, Syst. Nat., Ed. 10, p. 686, 1758; figured by Reeve, Conch. Icon., Vol. 14, pi. 2, figs. 2a, 26, 1863; also by Dall, U. S. Nat. Mus., Bull. 37, pi. 55, fig. 7, pi. 71, figs. 1, 3, 1889; etc.; see Schumacher's figure for hinge characters; Recent from Nova Scotia to Mexico; also fossil back to the Miocene. Shell large, heavy; radial sculpture absent, concentric sculpture of fine sharp growth lamellse or strise. The subgenus Mercenaria is represented by the type and several other species in the Tertiary and Quaternary of the Atlantic coast of North America. In the Pacific fauna V. stimpsoni Gould, of the Japanese region, is a typical Mercenaria. Venus kennicottii Dall' from Washington is so similar to the Atlantic V. mercenaria that the two are very difficult to distinguish; and the fact that it is very rare suggests that it may have been founded on adventitious specimens of the latter. Dall gives its range from Neah Bay, Washington, to Little River, Mendocino County, California. Genus PAPHIA Bolten, 1798 Pavhia Bolten, Mus. Boltenianum, p. 175, 1798; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 362, 1902; Trans. Wagner Inst. Sci., Vol. 3, pp. 1321-1324, 1903; Marwiek, Trans. New Zealand Inst., Vol. 57, p. 632, 1927; not Paphia Lamarck, 1799, nor 1801, nor Fabricius, 1808, nor Oken, 1815. Type (by subsequent designation, Dall, 1902), P. ala-papiUonis Bolten ( = V.rotun- data Gmelin, in part, not Linnseus) ; figured by Reeve, Conch. Icon., Vol. 14, Tapes, pi. 2, fig. 7, 1864; hinge figured by Marwiek, Trans. New Zealand Inst., Vol. 57, p. 632, fig. 3a, 1927; Indian Ocean. Shell elongate-ovate, flattened; surface jjolished and sculptured with rather distant concentric incised grooves; hmge rather narrow, with three cardinal teeth in each valve, the middle cardinal of the left valve and the middle and posterior cardinals of the right valve bifid, a long narrow pos- terior ridge or nymph in both valves; hinge-plate and teeth smaller than in Venus.. Marwiek (1927) has shown the differences in the hinges of Paphia and Tapes,'- his figures of the hinges being reproduced herewith. The most striking difference shown 1 Amer. Journ. Conch., Vol. 7, p. 147, pi. 16. fig. 1, 1871; Proc. U. S. Nat. Mus.. \'ol. 24, p. 560, pi. 40, fig. 7, 1902; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 155, pi. 14, fig. 7, 1924. 2 Megerle von Miihlfeld, Mag. Naturf. Freunde zu Berlin fur 1811, p. 51, fide Dall, 1903. ^'OLUME I 1 Pliocene and Pleistocene Mollusca of California 325 by Tapes litter atus, the type of Tapes, is in the very wide middle cardinal of the left valve, which is so deeply bifid that it is almost two teeth, and in the correspondingly wide inter- space of the opposing valve. The subgenus Tapes Megerle von Miihlfeld is interesting because it shows plainly one method by which the Venerid teeth multiply. The genus Saxidomus provides an- other example of this process. The fundamental liinge characters of the California species that have been assigned to Tapes and Paphia are identical with those of Paphia ala-papilionis Bolten; but the exter- nal sculpture is so different that the California species appear to be more closely related to the true Venerupis, under which they are here classed in subgenera. There are now, therefore, no California species of Paphia or of Tapes. Text figure 5. Illustration of the hinges of Paphia and Tapes, from Marwick, Trans. & Proc. New Zealand Institute, Vol. 57, New Issue, text figures 3a, Zb. 1927; reduced, X ?5- a. Paphia ala-papilionis Bolten. b. Tapes litteratus (Linnseus). Genus VENERUPIS Lamarck, 1818 Vemru-pis Lamarck, Hist. Nat. Anim. s. Vert., VoL 5, p. 506, 181S; Children, Quart. Journ. Sci., Lit., Arts, p. 303 January, 1823. Pullastra Sowerby, Genera of Shells, Pt. 28, 1826, type (by absolute tautonymy) Venus pullaslra Montagu. Type (by subsequent designation, Children, 1823), Venus perforans Montagu, Test. Brit., p. 127, pi. 3, fig. 6, 1803, a variety of Venus pullastra Montagu. Shell of moderate size and thickness, ovate-quadrate in outline, sculptured with concentric lines or threads of variable strength and wth strong or fine radial striations or ribs; hinge plate narrow, dentition like that of Paphia; pallial sinus of variable depth, ascending, rounded at apex. The recognition of the affinities of Ve7ius perforans was taken from Stewart' after this catalogue was in galley proof, and the name Venerupis was shifted to this group to replace Marcia, which was to have been used erroneously, sensu lata, with V. exalbida as the type, according to Ball's citation. Stewart has pointed out an earlier type designa- tion for Marcia, which makes Marcia apply to a peculiar smooth-shelled species, more hke dementia but heavier and with a different hinge. Stewart has also pointed out that Irus antedates Venerupis and would have to be used for the forms that have so commonly been called Venerupis, no matter what the latter name represents. Venerupis pullastra is a common, living, European species. It is radially striate and has the Paphia hinge; but it appears to be subgenerically distinct from all three of the California groups. The striations are fine and the hinge is weak, leaning toward Irus. Subgenus HUMILARIA, new subgenus Marcia sp., H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 423, Feb., 18.57, not the type, Venus pingids Chemnitz, designated by Kobelt, 111. Conch., Vol. 2, p. 339, 1881; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 360, 1902, type cited, Venus exalbida Dillwyn; Trans. Wagner In.st. Sei., Vol. 3, p. 1318, 1903. Type, Venus kennerleyi Carpenter in Reeve. Shell rather large, ovate-quadrate, flattened, beaks anterior; sculptured with fine concentric lines and periodic sharp lamellse but no radial sculpture; paUial sinus rather short, angular, but abruptly rounded at apex; anterior exi:remity of hinge buttressed just above the anterior adductor scar; valve margms crenulated or smooth. ' Stewart, Special Publication No. 3, Acad. Nat. Sci. Phila., p. 222, 1930. 326 San Diego Society of Natural History [ Memoirs If Ball's citation of the type of Marcia had been the first, the name would be avail- able for this group, even though Venerupis exalbida (Dillwyn)^ does not fit the generic description of Marcia, is not like the species that the Adams brothers had chiefly in mind in proposing the name, and is apparently unrelated to most of the species that have since been called Marcia by various authors, including Dall himself. In some respects this subgenus is more closely related to Mercenaria than to the radially striate Venerupis. It is interesting as a transitional group, intermediate between Mercenaria and Callithaca. In its sculpture, lunule, and pallial sinus it more closely resembles Mercenaria; but its shell is lower (i. e., of lower convexity), thinner, and much more elongate. In shape, in the modification of the dentition caused by the shape, and in the concentric sculpture it very closely resembles Callithaca; but it lacks the faint radial sculpture of the latter. Mercenaria in the genus Venus and Humilaria in the genus Venerupis are analogous as groups lacking radial striation in genera that are otherwise characterized by it. Perhaps Mercenaria should be used as a genus name, with Humilaria as a subgenus. Venerupis (Humilaria) perlaminosa (Conrad) Mercenaria -perlaminosa Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 7, pp. 267, 441, 1855; Gabb, Geol. Surv. Calif., PaliEO., Vol. 2, p. 22, pi. 5, fig. 38, 1866, p. 94, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 250, 1888; Ainold, V. S. Geol. Surv., Bull. 321, pp. 32, 76, pi. 12, figs, lo, lb, 1907. Venus perlaminosa Conrad, Arnold, Mem. Calif. Acad. Sci., Vol. 3, ]). 146, 1903; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, pp. 78, 81, 1929. Shell similar to that of Venertipis exalbida but with the umer valve margins finely crenulated, the umbones less erect, and the pallial sinus slightly narrower and ascending more rapidly. Type specimen: In the Academy of Natural Sciences of Philadelphia (?) Type locality: Near Santa Barbara, California, stated to be Miocene but probably Pliocene. This species is very similar to V. exalbida, only differing in the characters mentioned above. The valve margins are evenly and strongly crenulated, whereas the one specimen of exalbida in the Stanford collection shows no sign of crenulations on either valve. The purple color mentioned by Conrad in his description of perlaminosa is present on the shell of exalbida. Variety perlaminosa, s. s. Shell with tiie ventral margin evenly rounded, and the concentric sculpture less differentiated and more closely packed. Pliocene: Near Santa Barbara (Conrad, as Miocene, see Conrad, p. 441); Bath-house Beach and Packard's Hill, Santa Barbara (Arnold, 1903, 1907); Santa Barbara (Cooper, as Quaternary); Santa Barbara (Gabb, as Post-Pliocene beds on the beach) ; "Pico" near Ventura (Waterfall). The typical variety has a proportionally higher shell than the Recent variety, with a more convex, evenly rounded ventral margin. The concentric sculpture of the typical variety often lacks the sharp, erect, distant lamelliE of the Recent form, probably largely or entirely because of weathering. Some worn Recent specimens of the variety kennerleyi have the same concentric sculpture. 1 Venus exalbida Dillwyn, Cat. Shells, p. 170. 1817. as of Chemnitz. Conch. Cab., Vol. 11, pp. 225, 226. pi. 202. fig. 1974. 1793; also figured in Reeve, Coneh. Icon., Vol. 14, Venus, pi. 4, fig. 13, 1863; southern part of South America, Recent. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA . 327 Venerupis (Humilaria) perlaminosa (Conrad) variety keimerleyi (Carpenter in Reeve) Venus kennerleyi Carpenter MS., Reeve, Conch. Iron., Vol. 14, Veiiua, pi. 12, fig. 41, June, 1863; not "Venus kemierlyi Reeve ?" of Gabb, Geol. Surv. Calif., PalEeo., Vol. 2, p. 22, pi. 5, fig. 37, lS6fi, = Clemenlia (Egesla) pertenuis (Gabb). Marcia kennerleyi Carpenter M>S., Reeve, Dall, Proc. V. S. Nat. Mus., Vol. 26, p. 396, 1902. Mania kennerlyi (Carpenter) Reeve, Dall, U. S. Nat. Mus., Bull. 112, p. 42, 1921; Oklroyd, Stanford Univ. Publ. Geol., Vol. 1, ]). 15.5, pi. S, fig. 4, 1924. Shell with the ventral margin less strongly rounded, relatively more elongate, with distant erect concentric lanrellse. Type locality: Puget Sound; Recent. Recent: Kodiak Island, Alaska, to Santa Barbara Islands, California (Oldroyd). The Recent variety is more elongate than the typical variety of perlaminosa. The wearing off of the concentric lamellse produces a coarsely, irregularly undulate chalky surface. The inner margins of the valves are handsomely crenulated, even the margins at the liinule. Subgenus CALLITHACA Dall. 1902 Callilhaca Dall, Proc. II. S. Nat. Mus., Vol. 26, p. 364, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1326, 1903. Type (by original designation), Tapes tenerrima Carpenter. Shell with the shape and hinge characters of the subgenus Humilaria; sculpture with the con- centric lamellae of the subgenus Hvmilaria, either distant or closelj' packed, and with faint radial .striations; pallial sinus deep. This subgenus is like the subgenus Humilaria in its shape and concentric sculpture, but it is like Protothaca in its pallial sinus and non-crenulated inner margins. It has a much more flattened shell and less conspicuous radial sculpture than Protothaca. Venerupis (Callithaca) tenerrima (Carpenter) Plate 18, Figures 9a, 9b Tapes tenerrima Carpenter, Proc. Zool. Soc. London for 1856, p. 200; Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864; Gabb, Geol. Surv. Calif. Palseo., Vol. 2, p. 97, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 267, 1888; Keep, West Coast Shells, p. 157, fig. 136, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 151, pi. 14, fig. 6, 1903. Paphia {Callithaca) tenerrima Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 399, 1902. Paphia tenerrima Carpenter, Arnold, Proe. U. S. Nat. Mus., Vol. 32, p. 527, 1907; U. S. Geol. Surv., Bull. 396, p. 142, pi. 18, fig. 3, Jan. 15, 1910; Bull. 398, pi. 40, same figure, 1910; English, Univ. Calif. Publ. Geol., Vol. 8, pp. 210, 213, 1914; Martin, Vol. 9, p. 2.53, 1916; Nomland, Vol. 10, p. 219, 1917; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 272, pi. 22, figs, la, lb, 1918; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 563, 1922; Jordan, Vol. 15, p. 244, 1926. Paphia {Protothaca) tenerrima Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 43, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 156, pi. 30, figs, la, 16, 1924. Paphia {Callithaca) tenerrima alta Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 85, pi. 6, fig. 1, 1929. Shell rather large and flat, chalky, elongate ovate, with small anterior umbones; sculpture of periodically accentuated concentric raised lines and low radial threads; lunule faintly defined, escutcheon not defined ; hinge normal, with the left middle cardmal sometimes strongly bifid ; pallial sinus very deep, rounded on end. Average specimens about 70 mm. long and 55 mm. high, some- times much larger. Type specimens: Of tenerrivia, in the collection of the Boston Society of Natural History, fide Oldroyd; of variety alia, in the University of California collection, No. 31,418. 328 San Diego Society of Natural History [Memoirs Type localities: Of tenerrima, Panama, Recent; of variety alta, Hall Canyon, two miles northeast of Ventura, Pleistocene. Pliocene: Etchegoin of Coalinga region (Arnold) ; Chione elsmej-ensis zone, lower Pliocene of Coalinga region, common (Nomland); Purisima and Merced formations in the region south of San Francisco; Merced of Sargent oil field, Bolinas Bay, Afio Nuevo Bay (Martin); lower Fernando of Elsmere Canyon (Arnold; English) and of Holser Canyon, Los Angeles County (English); Pliocene at Santa Barbara (Cooper). Pleistocene: Northeast shore of Tomales Bay, Marin County (Diekerson) ; Santa Barbara (Cooper) ; Barlow's Ranch, Ventura County (Ai'nold) ; Hall and Harmon canyons, Ventura County (Waterfall, as variety alia); lower part of Pleistocene section near Santa Paula, Ventura County (U. S. G.); "rather rare" in the upper San Pedro series of San Pedro, Los Cerritos, Crawfish George's, and Deadman Island (Arnold) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jor- dan); etc. Recent: Puget Sound to San Quintin Bay, Lower California, Mexico (Dall, 1921); Panama (Carpenter). This species is easily recognized by its chalky white shell, rather evenly ovate, flattened shape, and low but sharp, fine sculpture. It is nearly identical in outline with Venerupis kennerleyi (Carpenter MS. in Reeve) ; but is lighter, flatter, has finer concen- tric sculpture and also radial striations, and the pallial sinus is much larger than the short, sharply angular sinus of kennerleyi. The variety alta, described by Waterfall, is based on an unusually high individual; but similar specimens occur living, and the form is probably not of significance. The form restorationensis FrizzelU of the late Pleistocene near Point Blakeley, Washington, appears to be a northern variety with a heavier shell and coarser radial sculpture. It is also more convex, and its general form shows better the relation- ship of this species with T'. staminea than does the typical variety. Subgenus PROTOTHACA Dall, 1902 Protothaca Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 364, Dec, 1902; Trans. Wagner Inst. Sci., Vol. 3, p, 1326, 1903. Type (by original designation), Chama thaca Molina, Saggio sulla Storia Naturale del Chile, p. 203, 1782 (-|- Vemis dombeii Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 590, 1818; figured by Reeve, Conch. Icon., Vol. 14, pi. 9, fig. 29, 1863; west coast of South America, Recent. Shell with the hinge of Paphia and of Venerupis, s. s., but with a shorter, more ventricose shape, with more uniform concentric sculpture, and equally strong radial ribs. It may be possible to substitute older names for Protothaca and Callithaca, but so much nomenclatorial revision is needed in the Veneridce that it is best to leave such mat- ters for a thorough review at a more opportune time. Protothaca has the hinge of Paphia, but its rough, sculptured surface is very different from the polished and concentrically grooved surface of Paphia ala-papilionis. Moreover, the shells of Protothaca are heavier, more ventricose, and less elongate. Venerupis (Protothaca) grata (Say) Venus grata Say, Amer. Conch., Pt. 3, pi. 26, 1S31; Reeve, Conch. Icon., Vol. 14, Venus, pi. 3, figs. 8a, 86, 1863. Venus histrionica Sowerby, Proc. Zool. Soc. London for 1835, p. 41, June,. 1835; Thes. Conch., Vol. 2, p. 714, pi. 155, fig. 52, 1853; Reeve, Conch. Icon., Vol. 14, Vemis, pi. 16, fig. 70, 1863. Venus fuscolineata Sowerby, Proc. Zool. Soc. London for 1835, p. 41, June, 1835; Reeve, Conch. Icon., Vol. 14, Venus, pi. 16, fig. 69, 1863. Vc7ius tricolor Sowerby, Proc. Zool. Soc. London for 1835, p. 41, June, 1835. ^ Paphia restoraXiunen^is Frizzell, Nautilus, Vol. 43, p. 120, .\pril, 1930. Volume I ] PLIOCENE AND PLEISTOCENE MOLLTJSCA OF CALIFORNIA 329 T'enits discors Sowerby, Proc. Zool. Soc. London for 1835, p. 42, June, 1835; Thes. Conch., Vol. 2, p. 698, pi. 151, figs. 148-150, 1853; Reeve, Conch. Icon., Vol. 14, Venus, pi. 7, figs. 22a, 226, 1863. Venus peclunculmdes Valenciennes, Voy. Venus, Atlas Zool., Moll., pi. 16, fig. 3, 1846, fide Lamy, 1909; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 203, 278, 1857; Rept. for 1863, p. 528, 1864. Tapes fusoli7ieata Sowerby, Thes. Conch., Vol. 2, p. 698, pi. 151, fig. 145, 1853. Tapes ffraia Say, Sowerby, Thes. Conch., Vol. 2, p. 699, pi. 151, fig. 152, 1853; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 77, 1857; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 155, 1894; Mabille, Bull. Soc. Philomathique de Paris, Ser. 8, Vol. 7, p. 75, 1895. Tapes tricolor Sowerby, Thes. Conch., Vol. 2, p. 699, pi. 151, fig. 153, 1853. Venus muscaria Reeve, Conch. Icon., Vol. 14, Venus, pi. 15, fig. 60, 1863. Paphia (Protothaca) grata Say, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 397, 1902. Venus {Paphia) grata Say, Lamy, Journ. de Conchyl., Vol. 57, pp. 246, 247, 1909. Paphia grata Say, E. K. Jordan, Bull. So. Calif. Acad. Sei., Vol. 23, p. 148, 1924. Pleistocene: Lower Quaternary of Magdalena Bay, west coast of Lower California, Mexico (Jordan). Recent: Turtle Bay, Lower California, Mexico, to Antofagasta, Chile (Jordan). Color variability has been the principal cause for the overnaming of this handsome species. It is certainly closely related to V. staminea, but may possibly be distinguished specifically by its color patterns (which vary greatly) and its shorter pallia! sinus. The elements of the hinge are essentially the same, and the sculpture can be matched on speci- mens of sta7ninea. V. grata has been reported from San Pedro, and it is possible that it intergrades with staminea, in which case the latter should be considered a variety of the earlier described species. Venerupis (Protothaca) staminea (Conrad) Plate 18, Figures la, lb, '2a, 26 Vemis staminea Conrad, Jeurn. Acad. Nat. Sci. Phila., Vol. 7, p. 250, pi. 19, fig. 15, 1837. Venerupis petitii Deshayes, Rev. Zool. Soc. Cuvierenne, p. 359, 1839; Mag. Zool., Moll., pi. 39, 1841, /ide Dall, 1921; Grewingk, Russisch-Kaiserliche Mineralogische Gesellschaft zu St. Petersburg, Verhandlungen for 1848 and 1849, p. 351, pi. 5, figs. 2a-f, 1850.1 Tapes diversa Sowerby, Thes. Conch., Vol. 2, p. 697, pi. 146, fig. 41, 1853; Conrad, U. S. Pac. R. R. Repts., Vol. 5, pi. 4, figs. 31, 31a, 316, 1856. Vmus dispar Gould MS., Carpenter, Brit. .\ssn. Adv. Sci., Rept. for 1856, pp. 196, 305, 351, 1857. Venus ampliata Gould MS., Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 213, 305, 348, 1857. Venii^ mundulus Reeve, Conch. Icon., Vol. 14, Venus, pi. 14, fig. 51, 1863. Tapes staminea Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 266, 1888; Keep, West Coast Shells, p. 185, fig. 158, 1888, 1892; Dall, 17th Ann. Rept. U. S. Geol. Survey, Ft. 1, p. 844, 1896; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 150, pi. 14, fig. 4, 1903. Tapes staminea Conrad, var. orbella Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864. ? Dosinia staleyi Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 24, pi. 7, fig. 42, 1866. Tapes staleyi Gabb, Geol. Surv. Calif., Pala!o., Vol. 2, p. 57, pi. 16, figs. 17, 17a, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 266, 1888. Paphia staminea var. sulculosa Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 399, pi. 14, fig. 2, 1902. Paphia (Protothaca.) staminea Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 397, 1902; U. S. Nat. Mus., Bull. 112, p. 43, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 156, pi. 35, figs, la, 16, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Ait. 22, p. 6, 1925. Paphia staminea var. orbella Carpenter, Dall, Proc. V. S. Nat. Mus., Vol. 26, p. 398, 1902; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 271, pi. 19, fig. 6, 1918. Protothaca greicingki Dall, Wash. Acad. Sci., Alaska., Repts. Harriman Alaska E.xped., Vol. 4, p. 116, 1904. Chio7ie staleyi Gabb, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 121, pi. 13, fig. 6, 1909; Amer. Journ. Sci., Ser. 5, Vol. 4, p. 311, 1922. Paphia (Tapes) statleyi Gabb, Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 209, pi. 4, figs. 38a, 386, 38c, 1909. Paphia staleyi ? Gabb, Arnold, U. S. Geol. Surv., Bull. 396, p. 158, pi. 26, fig. 8, Jan. 15, 1910; Bull. 398, pi. 48, same fig., 1910. ^ Eichwald, p. 130, 1871, states that Grewingk's Venerupis petitii came from the Cretaceous and renames it Venus costato-sguarnosa. Ball's grewingki is therefore a synonym of this form. See the note on Mya arenaria variety profundior, p. 414. 330 San Diego Society of Natural History [Memoirs Paphia sinmi.hea Conrad, Thompson, Rept. Brit. Columbia Comm. Fisheries for 1912, pp. 1-38, 1-47, pi. 2, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 419, pi. 5G, fig. 5, 1915; Martin, Vol. 9, p. 2.53, 1916; Nomland, Vol. 10, p. 219, 1917; Packard, Univ. Calif. Publ. ZooL, Vol. 14, p. 270, pi. 21, figs, la, lb, pi. 45, 1918; E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 2, p. 2, 1919; Weymouth, Calif. State Fish and Game Comm., Fish Bull. No. 4, pp. 11, 38, pi. 10, fig. 2, 1920; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 563, 1922; E. K. Jordan, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 253, 1929. Paphia sialeyi Gabb, Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 590, 593, 1913; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916; Nomland, Vol. 10, p. 219, 1917; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922; Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 49, 1926. Paphia alamiiiea var. diversa Sowerby, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. Paphia (Protothaca) staminea petitii Deshayes, Dall. U. S. Nat. Mus., Bull. 112, p. 43, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 157, 1924. Paphia (Protothaca) slamiiiea spatiosa Dall, U. S. Nat. Mus., Bull. 112, p. 43, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 158, pi. 9, fig. 1, 1924. Paphia (Protothaca) staminea arbella Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 43, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 157, pi. 33, fig. 6, 1924. Paphia (Protothaca) staleyi Gabb, var. hannibali Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 98, pi. 10, fig. 1, 1922. Shell subovate, variable, inflated, beaks anterior; sculpture of radial striae or ribs and eoncentric strise or ridges; hinge normal, as in Venerupis grata (Say). Variety staminea, s. .s. Shell with concentric and radial sculpture about equally well developed or with the radial more robust; outline and hinge normal. Size, often between 30 and 50 mm. in length. Type specimens: Of staminea, in the Academy of Natural Sciences, Philadelphia ?; of hannibali, No. 58 in the collection at Stanford University. Type localities: Of staminea, California, Recent; of staleyi, "from the Pliocene on Mark West Creek, a branch of Russian River, Sonoma County ;"of hannibali, Pliocene at Scotia, California. Miocene: "West of San Jose, Santa Clara County; Foxin's, Santa Barbara County" (Cooper); Miocene of St. Paul Island, Pavloff Bay, and Unga Island (Dall, 1896); San Pablo formation, upper Miocene of middle California (Clark; Nomland); Santa Margarita formation, upper Miocene of Coalinga region (Nomland); as staleyi: Miocene of Coos Bay, Oregon (Dall); Empire formation of Coos Bay, Oregon (Arnold and Hamiilial) ; Quillayute, Washington (Reagan), probably reworked Empire sandstone. Pliocene: "Santa Rosa, Sonoma County; Twelve-Mile House, San Mateo County; Kirker's Pass, Contra Costa County |? Pliocene]; Monterey; San Fernando, Los Angeles County" (Cooper); Pacific Beach and Russ School, San Diego (Arnold); lower Merced, San Mateo County (Nomland; etc.; Martin, as var. diversa); Etchegoin of Sargent oil field (Martin, also as var. orbella); etc.; as staleyi: Sonoma County at the type locality (Gabb); Eagle Prairie, Humboldt County; Santa Rosa, Sonoma County; Kirker's Pa.ss, Contra Costa County jPliocene ?]; Santa Cruz (Cooper); Etchegoin formation at various localities (Arnold; Martin; etc.); middle Wildcat formation of Humboldt Coun- ty (Martin); Purisima and Merced formations of middle California (Martin; Nomland); Pliocene of Sargent oil field (Nomland); lower Pliocene of Fugler's Point, Santa Barbara County (Carson); etc.; also reported from .some of these localities as hannibali (Howe). Pleistocene: "Rare in the lower San Pedro series at Deadman Island, San Pedro" (Arnold); lower San Pedro fauna at Nob Hill cut (Oldroyd) ; "Saugus" near Ventura (Waterfall) ; lower Quaternary at Magda- lena Bay, Lower California, Mexico (Jordan) ; east side of Tomales Bay, Marin County (Dickerson) ; Chiton bed, near San Pedro (Chace) ; common in upper San Pedro series at and near San Pedro and at Long Beach; Twenty-sixth Street and Spanish Bight, San Diego (Arnold); west side of Point Loma, near Moreno, near Torrey Pines, etc., San Deigo (Stephens); upper Pleistocene at San Quin- tin Bay, Lower California, Mexico (Jordan, 1926); etc. Recent: Aleutian Islands south to Kamchatka and northern Japan, and to San Quintin Bay, Lower California, and Socorro Island. Venerupis staminea is an abundant, long-ranging species with many variations and many names, but with only a few varieties worthy of notice. It is even probable that Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 331 staminea is merely a variety of grata, in which case staminea and its varieties should be treated as varieties under the older name. A very well known synonym is staleAji (Gabb), originally described as a Dosinia from a specimen without sculpture and with a shape quite different from that of a Venerupis of this group. Later Gabb found a better specimen of what he thought was the same species, and figured the hinge {op. cit., pi. 16, fig. 17a), which is the hinge of a Venerupis. Since then the name has been extensively used for forms, some of which are surely staminea; and so far as the present writers know, no one has at- tempted to show that there is any species distinct from staminea to which the name can or should be applied. Howe's variety hannibali has a more compressed shape, especially at the posterior end, but it is apparently without significance. Venerupis (Protothaca) staminea (Conrad) variety laciniata (Carpenter) Tapes ladniala Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 641, 1864; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 150, pi. 14, fig. 5, 1903. Paphia staminea var. laeiniaia Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 398, 1902. Paphia {Protothaca) staminea laciniata Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 43, 1921 ; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 1.57, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Pleistocene: Upper San Pedro series at San Pedro, "rather rare"; common at Los Cerritos (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Unalaska, Alaska, to San Diego, California (Dall). The shells which have received this name are large (65 mm. long, 57 mm. high), heavy, and the narrow but prominent ribs are crossed by strong concentric riblets, some- times spinose at their intersections. This presumed variety may prove to be merely a response to ecologic conditions. Such "varieties" as "orbella" are certainly (and generally admittedly) mere reflections of their particular habitat, the globose form of "orbella" being due to the confinement of pholad holes. The form called "spatiosa" is not dis- tinctive. It may be necessary to substitute the varietal name petitii Deshayes for laciniata. Venerupis (Protothaca) staminea (Conrad) variety ruderata (Deshayes) Plate 18, Figures 3a, 3b Chione ruderata Deshayes, Cat. Conch. Coll. Brit. Mus., Pt. 1, p. 136, 1853. Venus ruderata Deshayes, Reeve, Conch. Icon., Vol. 14, Venus, pi. 25, fig. 130, 1864. Paphia staminea var. ruderata Deshayes, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 398, 1902. Paphia (Protothaca) staminea ruderata Deshayes, Dall, U. S. Nat. Mus., Bull. 112, p. 43, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 157, 1924. Shell sculptured with concentric lines elevated into strong irregular laminae as in Venerupis, leaving the radial sculpture very subordinate; outline made irregular by the burrowing habit, and the hmge becoming narrower and degenerate. Type specimen: In the British Museum. Type locality: California; Recent. Pleistocene: Late Pleistocene terrace along beach southwest of Goleta, Santa Barbara County, localities 40 and 74 (coU. by U. S. G.). Recent: Southern Bering Sea to Lobitas, California (Dall). This variety is of considerable interest as it shows a transitional step toward Irus. However, the radial riblets, which tend to occur in pairs, have a Chione aspect. It is an inhabitant of holes in rocks. 332 San Diego Society of Natural History [ Memoirs Genus IRUS Oken, 1815 Irus Oken, Lehrbuch Zool., p. 230, 1815. Type (by absolute tautonymy), Donax irus Linngeus, figured by Sowerby in Reeve's Conch. Icon., Vol. 19, Venerupis, pi. 4, sp. 22, 1874; living, Great Britain. Shell of small or medium size and thickness; sculptured with periodically elevated concentric lamellae, and on the early part of the shell fine radial striations ; hinge similar to the hinges of Paphia and Venerupis, except that the hinge plate is narrower and the teeth usually small and degen- erate. This genus appears to be a specialized derivative of Venerupis, modified in characters by the burrowing habit assumed by the animal. It lives in holes burrowed Pholad fashion into soft mudstones, and like Petricola may take almost any shape according to the vary- ing hardness of the surrounding material. The variety ruder ata of Venerupis staminea is an independent adaptation of a related Venerid to similar conditions, and shows how close the relation is between Venerupis and Irus. There appears to be but one Recent species of Irus in the California fauna. It ranges back into the Pleistocene and possibly into the Pliocene. The present authors have a manuscript note referring to a specimen of Irus foliaceus (Philippi) from the upper Pleistocene of the coast of Oaxaca, Mexico, collected by R. H. Palmer, but the specimen is at present unavailable for study and the identification is probably wrong. PhiUppi' reported his species from the Red Sea and from Madagascar. Irus lamellifer (Conrad) Plate 18, Figures 5a, 56, 6a, 6b, 8 Vemts lamellifera Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 251, pi. 19, fig. 19, 1837. Petricola cordieri Deshayes, Rev. Zool. Soc. Cuvierenne, Vol. 2, p. 358, 1839. Rupellaria lamellifera Conrad, Carpenter, Proc. Zool. Soc. London for 1856, p. 214; Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 262, 1888; Keep, West Coast Shells, p. 183, fig. 156, 1888, 1892. Veneruyis lamtllifera Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 400, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1328, 1903; U. S. Nat. Mus., Bull. 112, p. 44, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 160, pi. 39, fig. 8, 1924. Petricola (Rupellaria) lamellifera Conrad, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 155, 1903. Variety lamellifer, s. s. Shell variable in shape, moderately heavy, with strong, distant, concentric lamellae. Pliocene: Monterey ? (Cooper, as questionably Pliocene). Pleistocene: Upper San Pedro of Deadman Island, Los Angeles County (Arnold); Santa Barbara (Cooper). Recent: Monterey to San Diego, California (Dall). Irus lamellifer (Conrad) variety prelamellifer, new vaiicty Plate 18, Figure 7 Shell like that of the typical variety, but with thuuier, more distant lamellae appearing earlier on the valves, and with perhaps more normally circular shape. Type specimen: In the collection of the San Diego Society of Natural History, No. 157. Type locality: Pacific Eastern Production Company's well No. 1, KCL-B, Sec. 21, T. 29 S., R. 27 E., Fruitvale District, Kern County, near Bakersfield, Cahfornia, depth 4859 feet, upper (possibly middle) Miocene (H. R. G.). ' Abbild. Besohr. Conchyl., Vol. 2, Heft 4, p. 107, Venus, pi. 5, 6g. 1, August, 1846. "Patria: Mare Rubrum; Madagascar (Petit)." Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 333 Miocene: At the type locality, from a well core near Bakersfield, California. The type specimen of this new variety is a right valve showing the high, thin lamellae, the fine radial sculpture, and the circular shape. A fragment of the left valve was found with it. From the same well at a depth of 5528 feet there was a specimen of the left valve in a hard matrix but broken so as to show the interior view of the hinge. The middle and anterior cardinals are of the same strength, showing the species to be an Irus, not a Circomphalus. The shell has much the appearance of Circumphalus calophylla (Hanley), Uving in China. Species of Irus vary so much in character that it is possible that this form is a variation of I. lamelUfer which had softer material to burrow in, or it may not have bur- rowed at all. However, the living species appears to have abandoned such habitats, and now burrows in soft or even hard rocks, like the Pholadidoe. Genus CLEMENTIA Gray, 1842 Clemenlia Gray, Synop. Cont. Brit. IMus., Ed. 44, p. 75, 1S42 (genus without species), fide Woodring, 1926; Proc. Zool. Soc. London for 1847, p. 184, 1847; DaU, Proc. U. S. Nat. Mus., Vol. 26, p. 348, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1234, 1903; Jukes-Browne, Proc. Malac. Soc. London, Vol. 11, p. 85, 1914; Woodring, U. S. Geol. Surv., Prof. Paper 147-C, 1926; Palmer, Palaeo. Amer., Vol. 1, p. 409, 1927-29. Blainmllia Hupe, Rev. Zool., p. 219, 1854, not BlaimnlUa Desvoidy, Mem. Pr^s. Ac. Roy. Sci. Insst. France, Vol. 2, p. 514, 713, 18.30, Diptera, fide Dall. Type (designated by Gray, 1847), Venus papyracea Gray, Ann. Philos., New Series, Vol. 9, p. 137, 1825; Wood, Suppl. Index Test., p. 5, pi. 2, fig. 8, 1828; also figured by Palmer, op. cit., text fig. 32 (hinge), and pi. 56, figs. 2, 5, 9, 11, 14, 1927-29; Philippine Islands and East Indies, Recent. Shell oval or oblong, convex, thin or substantial, sculpture generally concentric and feeble, but sometimes reticulate; Imiule iiadefiiiite or feebly defined; escutcheon generally depressed, but not defined; valve margins smooth, the right posterior dorsal margin grooved; hinge plate weak or strong in relation to the thickness of the shell, with a concave expansion in front of the teeth; three diver- gent teeth in each valve, the right posterior bemg generally bifid or composed of two laminae; the left posterior a short tooth crossmg the hmge plate; pallial sinus variable. Animal having long siphons, united along their whole length, with plain orifices; foot compressed and subquadrate (or hatchet- shaped), like that of Dosinia; mantle margins plain. (Jukes-Browne.) This genus has been discussed by Dall, Jukes-Browne, Woodring, and others. Palmer has recently discussed and figured the Atlantic coast species and refigured the genotype. dementia occurs from the Eocene to the Recent. The living species occur in the tropical and temperate zones.' Subgenus COMPSOMYAX Stewart, 1930 Compsomyax Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 224, 1930. Type (by original designation) Saxidomus gibbosus Gabb = dementia subdiaphana Carpenter. Shell like that of the tj'pical subgenus but somewhat heavier, the shape more ovate, with lower beaks, and the posterior right cardinal tooth more deeply bifid, the two divisions of this tooth diverg- ing widely. Typical dementia has a very thin shell and more prominent beaks, and its posterior right cardinal is long and straight, narrowly bifid, consisting of two thin, equal laminae. The posterior right cardinal of Compsomyax consists of two diverging laminae, the hinder 1 Woodring, op. cit., p. 27, fig. 1, indicates on a map the present range and former distribution of dementia, a. a., and of Egesta. 334 San Diego Society of Natural History [Memoirs of which is longer than the other. Flaventia Jukes-Browne' has almost exactly the same distinguishing characteristics, but the writers hesitate to introduce the name from the Cretaceous without a specimen of the type species. Flaventia appears to be more ovate, the right anterior cardinals are not so close together, and Jukes-Browne emphasizes the circumscribed lunule. The deeper splitting of the right posterior cardinal in both Flaventia and Compsomijax may be merely a function of the heavier shells. The subgenus Egesta may be still more closely related to typical dementia and might better be con- sidered a section. True Marcia appears to be entirely distinct. Clementia (Compsomyax) subdiaphana Carpenter Plate 17, Figures 10a, 10/), ? 15 Clementia subdiaphana Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 602, 607, 640, 1864; Proc. Acad. Nat. Sei. Phila. for 1865, p. .56; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 235, 1888; Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 185, pi. 7, figs. 5, 6, 1891. Callista subdiaphana Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 144, pi. 13, fig. 4, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 544, pi. 49, fig. 3, 1907. Callista subdiaphana Carpenter, var. pedroana .Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 144, pi. 13, fig. 2, 1903. Marcia sitbdiaphana Carpenter, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 123, 1909; English, Univ. Calif. Publ. Geol. Vol. 8, p. 210, 1914; Martin, Vol. 9, p. 252, 1916; Dall, U. S. Nat. Mus., Bull. 112, p. 42, 1921 ; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92 and table opp., 1922; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 155, pi. 38, fig. 1, pi. 33, fig. 3, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. "Marcia oregonensis Conrad," Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 593, 594, not pp. 583, 584, questionably p. 588, 1913; not Cytherea oregonensis Conrad, nor "Mnrcia oregonensis" Dall, 1909, nor Weaver, 1912, etc. Clementia obliqua Jukes-Browne, Ann. Mag. Nat. Hist., Ser. 8, Vol. 12, p. 59, pi. 1, figs. 1, 2, 1913. Shell of moderate size, sculptured only with fuie gro^rth lines, elongate-ovate, varying consider- ably in outline and ventricosity, beaks anterior to the middle and pointing forward, anterior slope short and abruptly descending, posterior dorsal margiii almost parallel for a short distance with the ventral margm, hmule broad and very famtly defined, escutcheon depressed but not defined; liinge like that of Pilar, but lacking the anterior left lateral ; valve margins smooth, pallial sinus broad and strongly ascending. Type locality: Puget Sound, Recent. f Miocene: Possibly in Empire formation ? (Howe, 1922). Pliocene: Lower Pliocene of Elsmere Canyon (.\rnold, 1907) and of Holser Canyon (English), Los .\ngeles County; Merced and Purisima formations of middle California (.\rnold and Hannibal; Martin); San Diego well (Cooper); "Pico"' near Ventura (Waterfall); ? Cape Blanco, Oregon. Pleistocene: "Pliocene" of Deadman Island and Timm's Point (Arnold, 1903); San Pedro to San Diego (Cooper); lower San Pedro series of Deadman Island (.Vrnold, as variety pedroana); "Saugus" near Ventura (Waterfall). Recent: Sannakh Islands, Alaska, to Santa Barbara Islands and San Pedro, C.nlifornia (Oldroyd). This species has been confused with "Marcia oregonensis Conrad" of Dall, which appears to be a misidentification of Pilar oregonensis (Conrad). Some of the above refer- ences and occurrences must be considered very doubtful, because of this confusion and the great similarity in the external appearance of this species to forms of Pilar occurring in the pre-Pliocene formations. Large specimens of this species reach a length of 70 mm., a height of 55 mm., and a convexity (of one valve) of 22 mm. The small shells which Arnold named variety pedroana are young or stunted specimens. > Proc. Malac. Soc. London, Vol. 8, p. 167, November 5, 1908, type (by original designation) Venus ovalis Sowerby, Cretaceous of England (Blackdown beds), hinge shown by Jukes-Browne, op. cit.. pi. 6, fig. 10. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 335 Subgenus EGESTA Conrad, 1845 Egesta Conrad, Foss. Tert. Form. United States, p. 70, 1845, reprint, Dall, p. 70, 1893; Woodring, U. S. Geol. Surv., Prof. Paper 147-C, p. 36, 1926. Type (by monotypy), Venus inoceriformis Wagner, Journ. Acad. Nat. Sci. Phila., Vol. 8, pp. 51-52, pi. 1, fig. 1, 1839; also figured by Glenn, Maryland Geol. Surv., Miocene Volume, p. 315, pi. 82, figs. 1, 2, 1904; and by Palmer, Pateo. Amer., Vol. 1, pi. 56, figs. 10, 13, pi. 57, fig. 13a, 1929; Maryland, middle Miocene. According to Woodring, "The larger and heavier shell, flattened or concave upper posterior slope, accompanying truncation of the posterior end, longer and deeper resilium groove, heavier hinge, and narrower pallial sinus separate Egesta from dementia, s. s." The Inoceramus-like concentric waves are also conspicuous, at least in most cases. Clementia (Egesta) pertenuis (Gabb) Venus kennerlyi Reeve, Gabb, Geol. Surv. Calif., Pal»o., Vol. 2, p. 22, pi. .5, fig. 37, 1866; not V. kennerleyi Carpenter in Reeve, = Ve7ierupis perlaminosa (Conrad). Venus jiertenuis Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, pp. 55-56, pi. 5, fig. 37, 1868-9; Branner, Newsom, and Arnold, U. S, Geol. Surv., Folio No. 163, p. 6, 1909; Arnold, U. S. Geol. Surv., Bull. 396, p. 17, pi. 8, fig. 3, 1910; Arnold and Anderson, Bull. 398, pp. 85, 86, pi. 30, fig. 3, 1910; Smith, Proe. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 174, 1912. ? Venus (Chione) pertenuis Gabb, F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 3 (Geol.), Vol. 2, p. 195, 1905. Clementia (Egesta) pertenuis Gabb, Woodring, U. S. Geol. Surv., Prof. Paper 147-C, p. 40, pi. 16, figs. 1-6, 1926. Shell relatively thin, reaching a large size; shape variable, slightly or decidedly elongate, slightly inequilateral, anterior end extended. Lunular area moderately depressed. Sculpture consisting of coarse concentric waves and fine concentric threads. Near the ventral margin the waves are lower and more closely spaced, or they may disappear. Hinge of right valve consisting of a slender anterior cardinal, a heavier middle cardinal, and a long, slender, deeply bifid posterior cardinal; hinge of left valve consisting of a heavy anterior cardinal, a slightly heavier middle cardinal, and a long, thin posterior cardinal. Pallial sinus deep, very narrow, ascending. Holotype: length, 58 mm.; height, 52 mm. ; diameter (both valves), 24 mm. (Woodrmg.) Type specimen: In the University of California collection, No. 12,000. Type locality: Griswold's, on the road to New Idria, San Benito County, Temblor Miocene. Miocene: Vaqueros formation of California (Smith) ; middle Miocene, TurriteUa ocoyaiia zone, also Santa Mar- garita formation, upper Miocene, of a number of localities, in San Benito, Fresno, Kern, San Luis Obispo, Santa Cruz, and Los Angeles counties (fide Woodring, 1926). ? Pliocene:^ Lower part of Purisima formation in Santa Cruz Quadrangle, lower Pliocene (Branner, Newsom, and Arnold). This species appears to range from the lower Miocene to possibly the lower Pliocene, being rare in the upper limit of its range. Woodring lists all reported occurrences in his paper on Clementia referred to above. Genus LIOCYMA DaU, 1870 Liocyma Dall, Proc. Boston Soc. Nat. Hist., Vol. 13, p. 256, 1870; .\mer. Journ. Conch., Vol. 7, p. 145, 1871; Fischer, Man. ConchyL, p. 1086, 1887; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 364, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1.327, 1903. Type (by original designation), Venus fluctuosa Gould. * In U. S. Geol. Surv. Folio 163 some middle Miocene outcrops were erroneously mapped as Pliocene. In view of this it seems probable that Clementia pertenuis (Gabb) is in reality confined to tlie Miocene formations. 336 San Diego Society of Natural History [Memoibs Liocyma fluctuosa (Gould) Venus fluchiosa Gould, Rep. Comm. Zool. Surv. State Massachusetts, p. 107, 1838, 7iomen nudum; Invert. Mass., p. 87, fig. 5, 1840; Ed. 2 (Binney), p. 136, fig. 447. Venus astarlmdes Beck, Middendorff, Mai. Rossiea, Ft. 3, p. 56, fide Dall, 1870. Liocyma fiucluosa Gould, Dall, Proc. Boston Soe. Nat. Hist., Vol. 13, p. 256, 1870; Amer. Joum. Conch., Vol. 7, p. 145, 1871; U. S. Geol. Surv., 17th Ann. Kept., Ft. 1, p. 844, 1896 (erroneously as of Beck). Miocene: Miocene(?) of St. Paul Island, Alaska (Dall, 1896). Recent: North Atlantic and Arctic oceans. This small shell is rather flat, with a trigonal shape, and small, irregular concentric rugosities. It is an inhabitant of cold northern waters. Dall reported it in the north Pa- cific, but omitted it from his catalogue of 1921. Genus PSEPHIDIA Dall, 1902 Psephis Carpenter, Brit. Assn. Adv. Sci.,*Rept. for 1863, p. 640, 1864; Proc. Acad. Nat. Sci. Fhila. for 1865, p. 56; not Psephis Guen^e, 1854, Lepidoptera. Psephidia Dall, Journ. Conch,, Vol. 10, p. 243, 1902; Proc. U. S. Nat. Mus., Vol. 26, p. 366, Dec, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1333, 1903; Jukes-Browne, Ann. Mag. Nat. Hist., Ser. 8, Vol. 12, p. 480, 1913. Type (by subsequent designation, Dall, Dec, 1902), Psephis lordi (Baird). Shell small, trigonal or oval, smooth and polished or concentrically striated; lunula feebly de- fined but escutcheon not differentiated ; hmge with three entire cardinals ia each valve and no later- als; palUal smus small; very fine crenulations present at both extremities of ventral margins of valves. Animal with the mantle edges fused below, the siphons short, simple ; an anterior opening for the foot which is not byssiferous. ^ Jukes-Browne considered this group a subgenus of Gomphina Morch, taking as type for the latter Venus donacina Chemnitz. Psephidia lordi (Baird) Plate 15, Figures 5, 6, 7a, 76 Chione lordi Baird, Proc. Zool. Soc. London for 1863, p. 69, 1863. Psephis lordi Baird, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, pp. 602, 611, 641, 1864; Cooper, 7th Aim. Rept. Calif. State Mineralogist, p. 261, 1888; Nomland, Univ. Calif. Pub!. Geol., Vol. 10, table opp. p. 230, 1917. Psephidia lordi Baird, Dall, Journ. Conch., Vol. 10, p. 243, 1902; Proc. U. S. Nat. Mus., Vol. 26, jjp. 401, 407, pi. 16, fig. 5, 1902; U. S. Nat. Mus., Bull. 112, p. 44, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 161, pi. 6, fig. 3, 1924. Shell small, of an ovate-triangular shape, a smooth shining appearance, and a light ohve color. The surface is concentrically marked with slight grooves. The beaks are promuient and very shining. Internally the surface is white, the margins of the shell very finely crenulate, and the pallial impres- sion short and Vilimt. (Baird.) Type specimen : In the British Museum. Type locality: Esquimalt Harbor, Vancouver Island, British Columbia. The type from the crop of a pin-tail duck. Pliocene: Upper middle Etchegoin of Coahnga district (Nomland) ; questionably in the upper Etchegoin of the Southern California Gas Company's well No. 1-4, Kern County, at depths of 2900-3124 feet (H. R. G.). Pleistocene: Quaternary at Santa Barbara (Cooper). Recent: Unalaska, Alaska, to Coronado Islands, just off San Diego (Dall, 1921). 1 The anatomical characters are as given by Dall, Dec, 1902. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 337 The typical variety of lordi is smaller and more trigonal than the variety ovalis, according to Ball's figure of Baird's species. The form barbarensis Arnold is very smiliar in appearance and may be a synonym ; but as no authentic specimens of Arnold's form are available at this time, it is retained until a comparison can be made with Baird's type. Psephidia lordi (Baird) variety barbarensis Arnold Psephidia barbarensis Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 22, pi. 58, fig. 3, 1907; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916; Waterfall, Vol. 18, pp. 77, 78, 79, 81, 1929. Type specimen: In the V. S. National Museum, No. 165,238. Type locality: Bath-house Beach, Santa Barbara; upper Pliocene. Pliocene: Upper Pliocene at Bath-house Beach, Santa Barbara (Arnold). According to Arnold, "This species is higher and more trigonal in outline, has a straighter anterior margin, and a less conspicuous tooth than P. lordii Baird, which it resembles." Psephidia lordi (Baird) variety ovalis Dall Psephidia ovalis Dall, Proc. U. S. Nat. Mus., Vol. 26, pp. 401, 407, pi. 16, fig. 4, Dec, 1902; Berry, Nautilus, Vol. 22, p. 38, 1908, questionably as oralis: Dall, U. S. Nat. Mus., Bull. 112, p. 44, 1921 ; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 161, pi. 34, fig. 4, 1924. Shell small, white, polished, oval, subcompressed; surface with obsolete concentric threads near the anterior base, but over most of the disk smooth ; beaks small and very low, at about the anterior third of the length; Iimule elongated, extremely narrow, nearly as long as the anterior dorsal slope; escutcheon linear or none; interior white, the pallial sinus moderate, pomted; internal margin deli- cately striated; hinge well developed, like that of P. lordi, with three entire cardinals and no lateral anterior tooth. Length, 8.5; height, 6.5; diameter, 3.0 mm. (Dall, 1902.) Type specimen: In the U. S. National Museum, No. 163,089. Type locality: North side of Catalina Island, in 16 fathoms, gravel and sand (Dall.) Pliocene: Questionably as ovalis in the upper Pliocene deposit at Bath-house Beach, Santa Barbara, one valve (Berry). Recent: St. Paul Island, Bering Sea, to San Diego, California (Dall, 1921). A pair of valves of this form from San Pedro magnified fourteen times show very fine crenulations at and near both extremities of the ventral valve margins. No tangential grooves were visible, but a single, faint groove on one valve parallel to the growth lines appeared to be oblique at its extremities. The pallial sinus is definite and angular. The hinge is provided with three cardinals in each valve, the left anterior one being directed forward like a lateral. The variety ovalis is more oval and much less trigonal than the typical variety as illustrated in Dall's figure. However, as lordi is very variable in shape, this variety, like the others, is of doubtful value. Psephidia cymata Dall Psephidia cymata Dall, Proc. U. S. Nat. Mus., Vol. 45, p. 593, June 11, 1913; U. S. Nat. Mus., BuU. 112, p. 44, pi. 3, fig. 2, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 161, pi. 22, fig. 3, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In the U. S. National Museum, No. 266,158. Type locality: Near Cedros Island, Lower Cahfornia, in shallow water. 338 San Diego Society of Natural History [ Memoirs Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara Islands, California, to the Gulf of California (Dall). This species is distinguished by prominent concentric sculpture. Psephidia (?) salmonea (Carpenter) Psephis salmonm Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 261, 1888; Baker, Nautilus, Vol. 16, p. 42, 1902; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 152, 1903. Psephidia salmonea Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 44, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 162, 1924. Shell small, salmon colored, ovate but with the umbones rather prominent and nearly medial. Size, about 5 mm. in length and 4 mm. in height. Type specimen: In the British Museum. Type locality: Farallone Islands, west of San Francisco, California. Pliocene: Packard's Hill and Bath-house Beach, Santa Barbara (Arnold). Pleistocene: "Rare in lower San Pedro series at Deadman Island and San Pedro" (Arnold); Santa Barbara (Cooper) . Recent: Farallone Islands to San Diego; also at San Martin Island, Lower California, Mexico (Baker). Dall (1921) questioned the assignment of this species to the genus Psephidia. Genus TRANSENNELLA Dall, 1883 Transennella Dall, Proc. U. S. Nat. Mus., Vol. 6, pp. 340, 341, 1883; Fischer, Man. Conchyl., p. 1080, 1887; DaU, Proc. U. S. Nat. Mus., Vol. 26, p. 348, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1240, 1903; Jukes-Browne, Proc. Malac. Soc. London, Vol. 10, p. 34.5, 1913; Vol. 11, p. 60, 1914; Palmer, Palaeo. Amer., Vol. 1, p. 299, fig. 10, 1927. Type (by monotypy), Cytherea {Transennella ?) conradiana Dall, op. cit., p. 340, 1883; figured by Dall, U. S. Nat. Mus., Bull. 37, Ed. of 1903, pi. 90, fig. 6, 1903, not Dall, Proc. U. S. Nat. Mus., Vol. 24, pi. 31, figs. 5, 7, 1902, fide Palmer; also figured in Proc. U. S. Nat. Mus., Vol. 26, pi. 13, fig. 6 [not 5 as stated], and by Palmer, Palseo. Amer., Vol. 1, text fig. 10, and pi. 16, figs. 4, 8, 10, 1927-1929; Pleistocene and Recent of Florida. Shell small, trigonal, with lively coloration; smooth and polished or concentrically striate; hinge with three cartlmals in eacli valve, the middle left cardinal bifid; an elongate anterior lateral in the left valve, received in a sulcus in the right valve; lunule defined by an incised line, escutcheon not defined; nymphs without rugosities; pallial sinus angular, free below, obliquely ascending; internal margins of the valves sharply tangentially grooved with numerous sulci. (Dall, 1903.) Geologic range: Miocene to Recent. This genus differs from Psephidia in the presence of an anterior lateral tooth in the left valve. The species listed below is not typical of the genus and jirobably should be placed in a separate section or subgenus. The type species has strong oblique grooves on the margins of the valves. Transemiella tantilla (Gould) Plate 15, Figures 8a, 86 Venus tantilla Gould, Boston Journ. Nat. Hist., Vol. 6, p. 406, pi. 15, fig. 10, 1853. Trigonia tantilla Gould, Carpenter, Proc. Zool. Soc. London for 1856, p. 201. Venus rhysomia Gabb, Proc. Acad. Nat. Sci. Phila. for 1861, p. 371. Psephis tantilla Gould, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 640, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 261, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 153, pi. 13, fig. 5, 1903. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 339 Transennella tantilla Gould, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 384, 1902; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; DaU, U. S. Nat. Mus., Bull. 112, p. 41, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 150, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, .\rt. 22, p. 6, 1925; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pleistocene: "Rather common in the lower San Pedro series at Deadman Island and San Pedro" (Arnold); lower San Pedro fauna of Nob Hill cut, San Pedro, "very plentiful" (T. S. Oldroyd); "Saugus" formation near Ventura (Waterfall); Santa Barbara (Gabb; Cooper); Chiton bed at Point Firmin, Los Angeles County (Chace); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan); upper San Pedro series at Deadman Island, Los Cerritos, and San Pedro (Arnold). Recent: Sitka Harbor, Alaska, south to Lower California, Mexico (Dall, 1921); San Martin Island (Baker). Type locality: Santa Barbara, California; Recent. This species has three cardinal teeth in each valve with an anterior left lateral fitting into a socket in the right valve. The inner (lower) margin of this socket is a tooth-like ridge, and it is in line with another small tooth-hke ridge that is considered to be the an- terior cardinal. There is evidence of one or two oblique grooves on the two extremities of the valve margins, but these grooves are faint and far less clearly developed than those on the valve margins of T. conradiana, the type of the genus. This species is not a typical Transennella in the character of the valve margins, but it is not known how reliable the grooves are for purposes of classification. Recent specimens of this species are white, blotched with brown on the posterior fourth of the valves. Transennella tantiUa (Gould) variety califomica Arnokl Transennella californica Arnold, U. S. Geol. Surv., Bull. 396, p. 72, pi. 26, figs. 7, 7a, January 15, 1910; Bull. 398, pi. 48, same figures, 1910. Type specimen: In the U. S. National Museum, No. 165,553. Type locality: South end of Kettleman Hills, San Joaquin Valley, California; Pliocene. Pliocene: Upper part of the Etchegoin formation, upper Pliocene of the type locality (Arnold); Southern California Gas Company's well No. 1-4, Sec. 4, T. 28 S., R. 23 E., Kern County, depth, 3880 feet, probably upper Etchegoin (H. R. G.). According to Arnold, this shell differs from Recent specimens of tantilla in having a "perceptibly shorter and less acute posterior extremity, a more prominent beak, and a more deeply sulcated and more anteriorly located forward cardinal tooth." The type is a well-preserved right valve. Genus TIVELA Link, 1807 Tivela Link, Beschr. Natur.-Samml. Rostock, Pt. 2, p. 1.52, 1807; Dall. Proc. U. S. Nat. Mus., Vol. 26, p. 349, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1243, 1903; Jukes-Browne, Proc. Malac. Soc. London, Vol. 10, pp. 266-270, 1913; Woodring, Carnegie Inst., Publ. No. 366, 1925; Palmer, Pal»o. Amer., Vol. 1, pp. 315, 316, 1927. Type (by subsequent designation, Dall, 1902), Venus corbicula Gmelin, = V. mac- troides Born, Index Mus. Cses. Vindob., p. 53, 1778; Test. Mus. Cses. Vindob., p. 65, 1780; figured by Palmer, Palso. Amer., Vol. 1, p. 315, text fig. 16, 1927, pi. 22, figs. 1, 4, 6, 15, 20, 21, 1929; West Indies to Brazil. Shell porcellanous, smooth, .sometimes heavy, trigonal, with prominent beaks and short but stout ligament ; hinge with three radiating cardinals in each valve, an anterior lateral in the left valve and a corresponding socket in the right valve, l)ut the teeth variable, sometimes with accessories; pallial sinus distinct, short or long. 340 San Diego Society of Natural History [ Memoirs This genus is a peculiar derivative of the Venerid family. It is similar in its charac- ters to Meretrix and is probably closely related to it. Both may have evolved from some form like Saxido^iuis, the size and position of the teeth being affected by the shape and to some extent by the habitat. It may be possible to trace Saxidomus back to some Paphia- like form in which the cardinal teeth have multiplied by division and the anterior cardinal has migrated forward to become the anterior lateral. In Tivela byronensis (Gray) one cardinal tooth in each valve has split, making four cardinals. Tivela stultorum (Mawe) Plate 19, Figures 3a, 3b, 8 Donax stultorum Mawe, Linn. Syst. Conch., pp. 37, 40, pi. 9, fig. 7, 1823; Gray, Index Test., Suppl., pi. 2, Donax, fig. 2, 1828. Cytherea (Trigonella) crassatellmdes Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 253, pi. 19, fig. 17, 1837. Cytherea crassatelloides Conrad, Reeve, Conch. Icon., Vol. 14, Cytherea, pi. 1, fig. 3, 1863. Cytherea (Tivela) a-assatelloides Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 21, pp. 371-378, pis. 23 to 25, 1898; Nautilus, Vol. 13, pp. 73-75, 1899. Pachydesma crassatelloides Conrad, Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 96, 1868-9; Cooper, 7th Ann. Rept., Calif. State Mineralogist, p. 256, 1888; Keep, West Coast Shells, p. 189, fig. 162, 1888, 1892. Tivela (Pachydesma) slvltorum Mawe, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 386, 1902; U. S. Nat. Mus., Bull. 112, p. 41, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 149, 1924. Tivela crassatelloides Conrad, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 143, 1903; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922. Tivela stultorum Mawe, Jukes-Browne, Proc. Malac. Soc. London, Vol. 10, p. 267, 1913; Weymouth, Cahf. Fish and Game Comm., Fish Bull. No. 4, p. 29, pi. 6, figs. 1, 2, 1920; Jordan, Bull. So. Cahf. Acad. Sci., Vol. 23, p. 148, 1924; I. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 6, 1925; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 252, 253, 254, 255, 1929. Shell large, very heavy; teeth heavy, short; valve margins smooth. Pliocene: Metced formation of Sonoma County (Dickerson). Pleistocene: "Rare in the lower San Pedro series of Deadman Island" (Arnold); Post-Pliocene at San Diego (Gabb) ; Santa Barbara to San Diego (Cooper) ; lower Quaternary at Magdalena Bay, Lower Cali- fornia, Mexico (Jordan, 1924); "common" in the upper San Pedro series of San Pedro, Los Cerritos, Long Beach, Crawfish George's, and Deadman Island (Arnold); at Twenty-six-th Street and at Spanish Bight, San Diego (Arnold; Stephens); Bay Point, Pacific Beach and Torrey Pines, San Diego (Stephens); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Halfmoon Bay, San Mateo County, to Lower California, Mexico. This species was figured by Mawe, who attributed it to the "Indian Seas," which must be an error, or else the California shell is not the one he figured and named. It is the "Pismo Clam" of commerce and is highly prized as a shellfish. Its habitat is along exposed sandy beaches, where its heavy shell protects it from the beating of the surf when the shifting of the sand exposes it to wave action. It is able to maintain itself at a rather uniform depth by its stout foot. Clark has described two species of Tivela and a variety' from the upper Miocene of California which are similar in general appearance to T. stultorum. Tivela trigonalis Nomland Tivela trigonalis Nomland, Univ. Cahf. Publ. Geol., Vol. 9, p. 207, pi. 9, figs. 2a, 26, 2c, 1916. Type specimen: In the University of California collection. Type locality: Near Coalinga; lower Pliocene. Pliocene: Middle Jacalitos to lower Etchegoin, lower Pliocene of Coalinga district (Nomland). This is a more inequilateral species than T. stultorurn, and the type is smaller than fully grown individuals of the latter. 1 Tivela {Pachydesma) diabloensia Clark, Univ. Calif. Publ. Geol., Vol. 8. pp. 462, 463, pi. 54, figs. 5, 8, pi. 55, fig. 1, 1915; T. (P.) diablo- ensis. var. angulaium Clark, op. cit., pp. 463, 464, pi. 56, fig. 1; and T. (P.) gabbi Clark, op. cit., p. 464, pi. 55, fig. 2, pi. 56. figs. 3, 4, 1915. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 341 Genus SAXIDOMUS Conrad, 1837 Saxido?mis Conrad, Journ. Acad. Nat. Sei. Phila., Vol. 7, p. 249, 1837; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 356, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1280, 1903. Type (by monotypy), Saxidomus nuttalli Conrad, 1837. Shell large, elongate-ovate and somewhat quadrate, gaping posteriorly, moderately inflated, umbones low; sculptured with concentric lines only, no defined lunule or escutcheon; ligament long, external; hinge with four teeth in each valve, in the right valve the posterior cardinal bifid, the middle cardinal normal, the anterior cardinal with a distal extension wliich might be considered a lateral, in front of which is another small tooth clearly a lateral, in the left valve the most anterior of the four teeth often considered a lateral, all teeth somewhat variable in development; behmd the teeth a small excavated area, and in line with the excavated area a long posterior ridge ; pallial sinus deep, broadly rounded on end; valve margms smooth. Geologic range: Tertiary to Recent, probably from the Oligocene. Distribution: North Pacific. This genus looks very much as if it had been derived from a group of Venerids, like some of the Paphias, in which the cardinal teeth have multiplied by division. The distinction between cardinal teeth and lateral teeth appears to be an artificial one, in this case more misleading than helpful. The anterior left lateral of Saxidomus is prob- ably of the same origin as the anterior left cardinal of Paphia; the two middle teeth of Saxidomus are the bifid middle cardinal of Paphia; and the posterior cardinals remain the same in each. Similarly, the two little anterior teeth in the right valve of Saxido- mus seem to be two divisions of the anterior cardinal of Paphia, the other teeth in the left valve and the posterior ridges in both valves still corresponding. Saxidomus nuttalli Conrad Plate 18, Figure 11 Saxidomus nuttalli Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 249, pi. 19, fig. 12, 1837; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 98, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 263, 1888; Stearns, Nauti- lus, Vol. 14, pp. 1-3, 1900; Dall, Proc. IT. S. Nat. Mus., Vol. 26, p. 391, 1902; Baker, Nautilus, Vol. 16, p. 42, 1902; Arnold, U. S. Geol. Surv., BuU. 396, p. 148, pi. 21, fig. 4, January 15, 1910; Bull. 398, pi. 43, same figure, 1910; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 420, 1915; Martin, Vol. 9, p. 253, 1916; Nomland, Vol. 10, pp. 220, 301, 302, 303, 1917; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 269, pi. 21, fig. 2, 1918; Weymouth, Calif. State Fish and Game Comm,, Fish Bull. No. 4, p. 35, pi. 7, figs. 1, 2, 1920; DaU, U. S. Nat. Mus., Bull. 112, p. 42, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 152, pi. 35, fig. 2, 1924; E. K. Jordan, Bull. So. Cahf. Acad. Sci., Vol. 23, p. 148, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 6, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 255, 1929. Venus maxima Anton, Philippi, Abbild. Beschr. Conchyl., Vol. 2, Heft 5, Venus, p. 151, pi. 2, fig. 1, 1846. Tapes gracilis Gould, U. S. Pacific R. R. Repts., Vol. 5, p. 333, pi. 19, fig. 20, 1855. Saxidomus aratus Gould, Otia Conch., p. 168, 1862; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 151, 1903. Type Specimen: In the Academy of Natural Sciences of Philadelphia. Type locality: "Inhabits the coast of California and Sta. Diego" (Conrad); San Diego {fide Oldroyd, 1924). The above synonymy seems to be beyond dispute. Philippi gave no locality for "Venus" maxima, but his figure represents Conrad's species. T. gracilis and S. aratus Gould {-\- S. ovatus Gould) are almost certainly synonyms. 342 San Diego Society of Natural History [Memoirs Variety nuttalli, s. s. Shell with conspicuous concentric rugae. Miocene: Monterey-Temblor, middle Miocene of California (Nomland); "Martinez; Walnut Creek, Contra Costa County; Santa Cruz ; Santa Inez, Santa Barbara County; Santa Monica, Los Angeles County" (Cooper, as S. gracilis Gould); upper San Pablo, upper Miocene of naiddle California (Clark); Santa Margarita formation at its type locality, in the Tejon Hills, and north of Coalinga (Nomland) ; etc. Pliocene: Etchegoin of Coalinga region (Arnold ; Clark) ; common in the Turritella nova and Pecten coalingensis zones of Coalinga region (Nomland) ; Etchegoin of Sargent oil field; also in the Merced formation of middle California (Martin); "Ivirker's Pass, Contra Costa County; Twelve-Mile House, San Mateo County; Santa Barbara; San Fernando, Los Angeles County" (Cooper, as S. gracilis Gould); Pico formation near Ventura (Waterfall); etc. Pleistocene: "Santa Barbara to San Diego" (Cooper); "Rare in lower San Pedro series of Deadman Island;" at Barlow's Ranch, near Ventura (Arnold); "Saugus" formation near Ventura (Waterfall); "not rare" in the lower San Pedro fauna of Nob Hill cut, San Pedro (T, S. Oldroyd); lower Quaternary at Magdalena Bay, Lower California, Mexico (E. K. Jordan, 1924); "common in the upper San Pedro series at Deadman Island, Crawfish George's, Los Cerritos, and San Pedro" (Arnold); foot of Twenty-sixth Street, San Diego (Arnold; Mrs. K. Stephens, MS.); Pleistocene shelf at Torrey Pines (F. Stephens); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Humboldt Bay, California, to Lower California, Mexico, San Martin Island (Baker). This is the southern variety, which is larger and more roughly sculptured than the variety giganteus (Deshayes). Saxidomus nuttalli Conrad variety giganteus (Deshayes) Plate IS, Figures 4, 10 Ve7ierupis gigantca Deshayes, Rev. Zool. Soc. Cuvierenne, \o\. 2, p. 359, Dec, 1839; Magasin de Zool., Moll., j)l. 43, 1841. Saxidomus gigajileus Deshayes, Dall, Proc. LT. S. Nat. Mus., Vol. 26, p. 391, 1902; Thompson, Kept. Brit. Columbia Comm. Fisheries for 1912, pp. 1-38, 1-47 (as aralus by mistake), pi. 1, 1913; Arnold and Hannibal, Proc, Amer. Philos. Soc, Vol. .52, pp. .596, 598, 1913; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. '253, 1916; Dal), U. S. Nat. Mus., BuU. 112, p. 42, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 153, 1924. Shell smaller than that of the typical variety, more circular in outlme, usually with finer concen- tric sculpture, which is sometimes periodically accentuated. Pliocene: Lower part of the Merced formation south of San Francisco (Martin); upper Pliocene of the Elk River formation, Elk River, Port Orford, Oregon (Arnold and Hannibal). Pleistocene: Saanich formation of Puget Sound and Straits of Georgia (Arnold and Hannibal). Recent: Aleutian Islands from Attn eastward and south to Monterey, California (Dall, 1921). This is the cooler water variety of Conrad's species. It varies somewhat in shape and greatly in the thickness of the shell, the individuals living in protected mud bottoms being thin shelled. From the fossiUferous beds on Popof Island, Alaska, presumed to be of Miocene age, Dall has described' Saxidomus popofianus. His figure is of a less elongate shell than S. nuttalli, with a much shorter pallial sinus. No external shell layer is shown in the figure. A short form, subtriangular, and smaller than nuttalli was described by Dall from the Recent fauna of the Admiralty Islands, Alaska, as variety brevis- of 5. giganteus (Deshayes). 1 Washington Acad. Sci., Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 115, pi. 10, fig. 4, 1904, reissued by the Smithsonian Institution, 1910. 2 Proc. U. S. Nat. Mus., Vol. 52, p. 413, no figure, December 27, 1916, type locality, Mole Harbor, Admiralty Islands, Alaska. VoLtTME I ) Pliocene and Pleistocene Mollusca of California 343 Genus MERETRIX Lamarck, 1799 Callisla Poli, Test. Utr. Sic, Vol. 1, p. 30, 1791, inconsistently considered not strictly binomial. Meretrix Lamarck, Mem. Soc. Hist. Nat. Paris, Ser. 1, Vol. 1, p. 85, 1799. Chimie Gray, The Analyst, Vol. 8, p. 305, 1838; not Chione Megerle von Muhlfeld, 1811, nor of Gray, 1847, nor 1851. Dione Gray, List. An. Brit. Mus., p. 6, IS51; fide Dall, 1903; not Dione Gray, 1847, nor EHone Hiibner, 1816, Lepi- doplera . Callisla Morch, Cat. Yoldi, Pt. 2, p. 2" 1853, not of Leach, Syn. Moll. Gt. Brit., p. 302, 1852 (edited by Gray), = Venus, s. s., typified by V. verrucosa; Palmer, Palso. Amer., Vol. 1, p. 279, el seq., 1927. Type (by monotypy), Venus meretrix Linnseus; figured by Reeve, Conch. Icon., Vol. 14, Cytherea, pi. 3, fig. 10, 1864; Recent, Philippine Islands and China. Shell of medium to large size, subquadrate to subtrigonal in outline; exterior smooth; hinge with three radiating cardinal teeth in each valve, an anterior lateral in the left, and a corresponding socket bordered by lamuia? in the right, m each valve an excavated area behmd the beaks; pallial sinus very shallow. This old genus name applies to a well-characterized gi-oup of species, but it does not appear to be appropriate for any of the species represented in this catalogue. See the remarks below on Megapitaria. Genus MACROCALLISTA Meek, 1876 Macrocallisla Meek. Rept. U. S. Geol. Surv. Territories, Vol. 9, p. 179, 1876; Tryon, Struct. Syst. Conch., Vol. 3, p. 178, 1884; Fischer, Man. Conchyl., p. 1079, 1887; DaU, Proc. U. S. Nat. Mus., Vol. 26, p. 351, 1902; Trans. Wagner Inst. Sci., Vol. 3, pp. 1251, 1252, 1903; Palmer, Palso. Amer., Vol. 1, p. 279, 1927. Type (by monotypy), Venus gigantea Gmelin = Venus niinhosa Solander, figured by Reeve, Conch. Icon., Vol. 14, Dione, pi. 5, fig. 17, 1863, and by Palmer, Pateo. Amer., Vol. 1, p. 287, fig. 9, pi. 41, fig. 15, pi. 44, figs. 1, 4, pi. 45, fig. 18, 1927; North Carolina south to Cuba and the Gulf coast of the United States, Recent. Shell elongate-ovate, rather flattened; smooth or sculptured with incised concentric grooves; hinge with two cardmals and a long posterior ridge in each valve, an anterior lateral in the left valve, and a corresponding socket marked off by lamma in the right valve; pallial sinus moderately deep. This genus is probably closely related to Pilar, as pointed out below. There are a number of rather small species in the early Tertiary of the Pacific coast and possibly one in the Pliocene that appear to have the characters of Macrocallista; but the species from Lower California assigned to Macrocallista have probably been placed there erro- neously. The characters of Macrocallista recall those of Paphia, except that the hinge teeth of the t.wo valves interlock in different order. A study of Macrocallista might help to unravel the phylogenetic historj' of the Veneridce. Of the species from the Tertiary of California that have been assigned to Macrocal- lista some of the smaller, ovate shells, such as M. vespertina (Conrad), may belong to the section Paradione Dall.' Macrocallista ? densa Moody Macrocallista densa Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 58, pi. 2, figs, la, 16, 1916. Type specimen: In the University of California collection, No. 11,086. Type locality: Fourth and Broadway, Los Angeles; Pliocene. ' U. S. Geol. Surv.. Prof. Paper 59, p. 120, April 2, 1909. type designated Cytherea ovalina Deshayes; new name for Chionella Cossmann. Ann. Soc. Roy. Malac. Belg., Ser. 4. Vol. 1. p. 103. 1886; not Chionella Swainson. Treat. Malac. p. 335, note. 1840. Marwick (Trans. New Zealand Inst.. Vol. 57, p. 592, 1926.) describes the differences between Macrocallista. s. s., and Paradione Dall, which he believes should be genericaliy separated. Chionella Swainson was not tised in a generic sense. 344 San Diego Society of Natural History [Memoirs Pliocene: Four specimens from the type locality, lower part of the upper Pliocene (Moody). Moody mentions that this small ovate species possesses "unique characters in the placing of the laterals and in having both posterior cardinals bifid." Genus PITAR Romer, 1857 Piter Romer, Krit. Untersuch. Mollesk. Venus, p. 15, 1857; Meek, Kept. U. S. Geol. Surv. Territories, Vol. 9, p. 179, 1876; Bucquoy, Dautzenberg, and DoUfus, Moll. Mar. Roussillon, Vol. 2, p. 329, 1893; Woodring, Carnegie Inst., Publ. No. 366, p. 152, 1925. Caryatis Romer. Mai. Blatter, Vol. 9, p. 58, 1862; Stoliczka, Mem. Geol. Surv. India, Cret. Pelecyp. So. India, p. 151, 1871; not Caryatis Hiibner, 1816, Lepidoptera. "Pitono Romer em.," Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 353, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1264, 1903; Palmer, Palaeo, Amer., Vol. 1, p. 216, 1927. Type (by monotypy), Venus tumens Gmelin, figured by Palmer, Palaeo. Amer., Vol. 1, p. 216, fig. 2 (hinge); pi. 32, figs. 1, 4, 5, 6, 7, 1927-29, and by Tegland, Univ. Calif. Publ. Geol., Vol. 18, pi. 21, figs. 1-3, 1929; West Africa, the coast of Senegal, and the Gulf of Guinea, Recent. Shell of moderate size, ovate-subtrigonal, ventricose; sculptured with concentric gro^\'th lines; lunule rather wide, defined by an incised line, escutcheon not defined; hinge teeth consisting in the left valve of a large posterior cardinal, a thinner cardinal in front, and an elongate anterior lateral, and in the right valve of a strong posterior cardmal, two other cardinals close together, the anterior very thin, and an anterior socket, in both valves a long posterior ridge corresponding to the posterior ridge of Paphia and Venerupis and to the broad flattened area of Venus and Dosinia; pallial sinus pointed, reachmg to the middle of the valve; valve margins smooth. Amiantis Carpenter is closely related, but differs in hinge characters as follows: the left anterior lateral is more elongate, the left posterior cardinal is much more elongate, and the right anterior cardinal is very short, especially in old individuals. The other teeth are of the same general form though much heavier, as is to be expected in the larger, heavier shell of Amiantis. In shape the genotypes are similar, though Amiantis callosa is less ventricose. It also differs in being heavier and in being prominently sculptured with small concentric ripples. It is probable that Amiantis should be classed as a sub- genus of Pilar. For notes on the development of the hinge of Pitar, see the discussion of Dosinia. Pitar oregonensis (Conrad) Cytherea oregonensis Conrad, .\mer. Journ. Sci., Ser. 2, Vol. 5, p. 432, text fig. 8, 1848, republished by Dall, U. S. Geol. Surv., Prof. Paper 59, p. 150, fig. 8, 1909. "Marcia" oregonensis Conrad, of some authors, probably not of Dall, 1909. ? Pilaria elarki Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 7, p. 169, pi. 28, figs. 4a-c, 1917. ? Pitaria (Lamelliconcha) eocenica Weaver and Palmer, Univ. Wash. Publ. Geol., Vol. 1, No. 3, pp. 20, 21, pi. 10, figs. 14, 16, 1922. Type specimen: Location unknown, probably lost (fide Dall, 1909). Type locality: "Tertiary deposits on the Columbia River near Astoria" (Conrad). Oligocene or Miocene of Astoria, Oregon. There has been so much confusion between Conrad's oregonensis and Carpenter's dementia subdiaphana that it would be useless and misleading to give a long list of ref- erences to the literature without a careful examination of all the specimens upon which the records have been based. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 345 From a study of the original description and figure it appears that Conrad's "Cytherea" oregonensis was based upon a rather small shell with prominent umbones slightly anterior in position but quite unlike the Recent shell upon which Carpenter fixed the name dementia subdiaphana and similarly unUke the shells which Dall unfor- tunately figured as "Marcia oregonensis Conrad." In his original description Conrad remarked that his new species was "remarkably similar to C. ovata Rogers, a fossil of the Virginia Miocene, but it lacks the impressed concentric lines of that species." The "C. ovata Rogers,"! mentioned by Conrad in his comparison, is a typical Pitar, in shape nearly identical with Conrad's drawing, and quite unlike C. subdiaphana or the figures given by Dall for Marcia oregonensis. The figures of Pitar clarki (Dickerson), from the Gries Ranch fauna, presumably lower Ohgocene of Washington, and those of Pitar eocenicus (Weaver and Palmer) of the Cowlitz horizon, upper Eocene of Washington, suggest that possibly these two names may be synonyms of Conrad's P. oregonensis. The similarities are striking. Conrad also proposed two other names, Dione angustifrons and D. brevilineata, in the reports of the U. S. Exploring Expedition. These names apparently apply to similar forms fi-om the Tertiary of the Northwest, forms like Ball's figure of "Marcia oregonensis" and like P. dalli (Weaver), respectively. In a recent interesting paper, N. M. Tegland figured and discussed several species of Pitar from the Pacific coast Tertiaries, but did not attempt to add to our knowledge of Conrad's early described species. This may have been because P. oregonensis was con- sidered a Marcia, and the other species are little known. Ball's misidentification of Con- rad's species and his absurd assignment of it to the genus Marcia (which genus he had him- self tried to fix upon a large flattened Paphia-like shell) has had much to do with the confusion surrounding this group of species. In passing, it might be remarked that Ball's figures of "Marcia oregonensis" are suggestive of Weaver's Pitar dalli,'^ from the Wash- ington Oligocene. Pitar newcombianus (Gabb) Lioconcha newcomUana Gabb, Proc. Calif. Acad. Sci. for 1865, p. 189; Geol. Surv. Calif., Palaeo., Vol. 2, p. 96, 1868-9. Callista newcomUana Gabb, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 231, 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 187, pi. 23, fig. 4, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 143, 1903. Pitaria newcomUana Gabb, DaU, Proc. U. S. Nat. Mus., Vol. 26, p. 387, 1902; U. S. Nat. Mus., Bull. 112, p. 41, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 151, pi. 57, fig. 2, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Stephens, Trans. San Diego Soc. Nat. ffist.. Vol. 5, p. 251, 1929. Type specimen: In the University of California collection. Type locality: Catahna Island, California, in 120 fathoms. Pliocene: San Diego well, Balboa Park, San Diego (Cooper). Pleistocene: Rare in the upper San Pedro series at Deadman Island, San Pedro (Arnold) ; San Diego (Gabb) ; foot of Twenty-sixth Street, San Diego, abundant (Arnold; Stephens); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to the Gulf of CaUfornia and Clarion Island, Mexico (DaU, 1921). This is a plump ovate-trigonal shell with few faint zig-zag brown markings on the exterior of the valves. The left hinge has a strong anterior tooth. It is distinguished from ' Trans. Amer. Philos. Soc, N. S., Vol. 5, p. 340, 1836; Vol. 6, pi. 27, fig. 2, 1839; Meretrix omta Rogers. Clark and Martin, Maryland Geol. Surv., Eocene, p. 168. pi. 34, fig. 1, 1901: Pilario (Pi(aria) otaia (Rogers). Palmer, Pateo. Amer., Vol. 1, p. 219, pi. 4, figs. 3. 4, 20, 1927-9; Eocene of Virginia and Maryland. 2 Pitaria dalli Weaver. Univ. Wash. Publ. Geol., Vol. 1, p. 41, pi. 1, figs. 1-4, 1916; discussed and figured by Tegland, Univ. Calif. Publ. Geol., Vol. 18, p. 278, pi. 21, figs, 4-9, 1929. 346 San Diego Society of Natural Histoky [Memoirs Clementia subdiaphana when the hinges are not visible by its less elongate shape, by the more nearly central umbones, and by the smoother surface. It is relatively more ventri- cose and apparently averages smaller than C. subdiaphana. A manuscript note in our possession reports Pitaria concinna from the Oaxaca Pleisto- cene, collected by Palmer, but through some inadvertence the specimen has been mis- placed. Pitar barbarensis (Gabb) Caryalis barbarensis Gabb, Geo). Surv. Calif., Palaeo., Vol. 2, pp. 56, 95, pi. 15, fig. 15a, 1868-9. Pitar barbare7isis (Gabb), Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 234, pi. 16, fig. 5, 1930. Type specimen: In the Museum of Comparative Zoology, Harvard College, No. 15028 {fide Stewart). Type locality: Santa Barbara, "Pliocene." ? Pliocene: At the type locality. This species is based upon a single specimen, the relationships of which are not known. The specimen appears to be fairly well preserved and may have come from the Pliocene or possibly even from the Pleistocene. It is of somewhat different shape from P. newconihianus but may be a distorted form of it. Subgenus MEGAPITARIA, new subgenus Type, Cytherea aurantiaca Sowerby. Shell like tliat of the typical subgenus, with similar hinge, shape, and polished exterior, but very much hirger and heavier. The shells of this group have been assigned by Dall to Macrocallista; but although the hinge of Macrocallista contains the same elements, modified somewhat by the shape of the shell, the shape is so very different that the two should be separated at least subgenerically. Macrocallista is much more elongate, of ovate outline, and much de- pressed. An early Tertiary group apparently belonging to Macrocallista is characterized by incised concentric grooves. Megapitaria is more closely related to Pitar and Amiantis. It has the hinge, the shape, the pallial sinus, the heavy shell, and the size of Amiantis, from which it can be distinguished only by its smooth surface. The present writers wish to emphasize this relationship with Amiantis, which may even be closer than the relationship with Pitar, s. s. Perhaps the truest arrangement of all would be to consider Macrocallista, Megapitaria, Amiantis, and Hysteroconcha all subgenera of Pitar, all having the same hinge and being distinguished only by minor differences in shape, size, and sculpture. Megapitaria is as distinct as the others. Lamy has assigned aurantiaca and squalida to Meretrix, which is an older name and has the shape and smooth exterior. However, there appears to be a constant dif- ference between the hinge of Meretrix and the hinges of the groups here associated with Pitar. Meretrix has three cardinals in the right valve, of about equal strength and about equally spaced. The Pitar group has the two anterior cardinals of the right valve smaller and very close together, and in the left valve the anterior cardinal has become very thin to fit between them. Meretrix is probably generically distinct. It is interesting that "Cytherea" lyrata Sowerby has the Meretrix hinge and the Amiantis sculpture. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 347 Pitar (Megapitaria) aurantiacus (Sowerby) Cythcrea aurantiaca Sowerby, Geii. Rec. Foss. Shells, No. 33, Cyllierea, fig. 6, 1831; Reeve, Conch. Syst., Vol. 1, p. 94, pi. 69, fig. 3, 1841. Cytherea aurantia Gray, Analyst, Vol. 8, p. 305, 1838; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 75, 1895. Cytherea aurantia Hanley, Sowerby, Thes. Conch., Vol. 2, p. 628, pi. 132, fig. 97, 1851. Dione aurantia Hanley, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 63, 1857. Dione aurantia Gray, Reeve, Conch. Icon., Vol. 14, Dione, pi. 3, fig. 12, 1863. Cytherea (Callisia) aurantia Hanley, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 153, 1894. Macrocallista {Clnonella) aurantiaca Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 386, 1902. Meretrix {CaUista) aurantiaca Sowerby, Laniy, Journ. Conchyl., Vol. 57, p. 242, 1909. MacrocallislaaurantiacaSov;eThy, 'Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 266, 1909; Dall, West American Scientist, Vol. 19, p. 19, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 26, p. 141, 1927. Pliocene: Santa Antonita Point, Lower California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary at Magdalena Bay (Jordan), and upper Pleistocene at San Quintin Bay (Dall, 1921), both Lower California, Mexico. Recent: Gulf of California, Mexico, to Guayaquil, Ecuador (Dall). Pitar (Megapitaria) squalidus (Sowerby) Cytherea squalida Sowerby, Proc. Zool. Soc. London for 1835, p. 23, 1835; Gray, Analyst, Vol. 8, p. 306, 1838; Sowerby, Thes. Conch., Vol. 2, p. 629, pi. 131, figs. 87, 88, 89, 1851; MabiUe, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 75, 1895. Cytherea biradiata Gray, Zool. Beechey's Voy., Moll., p. 151, pi. 43, fig. 5, 1838. Cytherea chiomea Menke, Zeitschr. f. Malak., Jahrg. 4, p. 190, 1847, fide Lamy, 1909. Dione chiomea Menke, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 64, 1857. Dione squalida Sowerby, Reeve, Conch. Icon., Vol. 14, Dione, pi. 3, fig. 10, 1863. Cytherea {CaUista) cMonsea Menke, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 153, 1894. Macrocallista (Chionella) squalida Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 386, 1902. Meretrix (CaUista) squalida Sowerby, Lamy, Journ. Conchyl., Vol. 57, pp. 241, 242, 1909. Macrocallista squalida Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 266, 1909; Nautilus, Vol. 32, p. 24, 1918; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 148, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 141, 1927. Pliocene: Coronados Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Dall, 1918; Jordan, 1924); upper Quaternary at Scammons Lagoon, Lower California, Mexico (Jordan); upper Pleistocene of coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Cedros Island and Scammons Lagoon, Lower California, Mexico, to Peru. This rather heavy, large shell has an ovate shape, but the umbonal portion is promi- nent and anterior. It has a shiny, thin periostracum which cracks off when dry, leaving a smooth porcellanous surface of a light creamy or salmon color. The pallial sinus is not deep but very broad and hardly ascending. The valve margins are smooth. In the right valve there are three cardinal teeth; the posterior one is bifid and directed posteriorly and nearly parallel to the long axis of the shell; the middle and anterior are narrow, very close and long. Anterior to the cardinals there is a deep pit for the reception of the left lateral tooth. Below, the margin of the pit is developed into a low lateral tooth. In the left valve there is a strong, prominent lateral tooth, which is probably the anterior car- dinal moved forward ; the anterior cardinal is a thin wall joined above to the heavy middle cardinal. In the left valve there is no true posterior cardinal (fourth tooth) in this species, but the lower margin of the nymph (which is finely vertically crenulated) pro- jects shghtly. Pitar squalidus is more elongated and pointed at the extremities than P. aurantiacus, and the color differs. Mature specimens of squalidus average 120 mm. in length and 108 mm. in height, but some are much larger. 348 San Diego Society of Natural History [Memoirs Pitar (Megapitaria) orcutti (Dall) Macrocallisla orcutti Dall, Nautilus, Vol. 32, p. 24, July, 1918. Type specimen: In the U. S. National Museum. Type locality: Magdalena Bay, Lower California, Mexico; Pleistocene. Pleistocene: A single imperfect right valve at the type locality (Dall). This may prove to be a variety or synonym of P. squalidus. Genus AMIANTIS Carpenter, 1864 Amiantis Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, pp. 526, 640, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 178, March, 1865; Tryon, Struct. Syst. Conch., Vol. 3, p. 178, 1884; Fischer, Man. Conchyl., p. 1079, 1887; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 352, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1257, 1903; Jukes-Browne, Proc. Malac. Soc. London, Vol. 11, p. 60, 1913; Palmer, Palaeo. Amer., Vol. 1, p. 304, 1927. Type (by monotypy), Cytherea callosa Conrad. SheU large, heavy, ovate; sculptured with many rounded concentric riblets; lunule defined, escutcheon linear; hinge essentially the same as that of Pitar; valve margins smooth. This genus is closely related to Pitar and was probably derived from the same stock in the early Tertiary. Subgenus AMIANTIS, s. s. Shell heavy but without spines; hinge teeth heavy, except the anterior right cardinal, which is comparatively small; pallial sinus sharp. Amiantis callosa (Conrad) Plate 17, Figures 7, 9, 11, 12, 13, 14 Cytherea callosa Conrad, Journ. Acad. Nat. Sci., PhUa., Vol. 7, p. 252, 1837. Cytherea nohilis Reeve, Proc. Zool. Soc. London, Pt. 17, p. 126, 1850. Not "Venus callosa Conrad," Sowerby, Thes. Conch., Vol. 2, p. 712, pi. 154, figs. 44, 45, 55, 1853. Dosinia callosa Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 305, 349, 1857. Dione nohilis Reeve, Conch. Icon., Vol. 14, Dione, pi. 4, fig. 15, 1863. Amiantis callosa Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 526, 640, 1864; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 96, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 266, 1888; Keep, West Coast Shells, p. 187, fig. 160, 1888, 1892; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 387, 1902; English, Univ. CaUf. Publ. Geol., Vol. 8, p. 209, 1914; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 34, pi. 5, fig. 3, 1920; DaU, U. S. Nat. Mus., Bull. 112, p. 41, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 151, pi. 56, figs. 1, 2, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Palmer, PaliEO. Amer., Vol. 1, p. 96, 1927, pi. 16, figs. 22, 23, 24, 1929; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 253, 1929. CaUista (Amiantis) callosa Conrad, WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, p. 187, 1892; Arnold, Mem. Cahf. Acad. Sci., Vol. 3, p. 145, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 544, pi. 49, fig. 2, 1907. Type specimen: Of callosa, in the Academy of Natural Sciences of Philadelphia ? Type localities: Of callosa, near Santa Barbara, California, Rfecent; of nohilis, Cali- fornia, Recent. Variety callosa, s. s. Anterior dorsal margin not descending abruptly but extendmg outward for a short distance almost parallel to the ventral margin, the anterior extremity regularly and strongly curved. Miocene: Well core near Bakersfield, upper or possibly middle Miocene (H. R. G.). Pliocene: Lower Pliocene of Elsmere Canyon, Los Angeles County (Arnold, 1907); lower Fernando of Els- mere, Holser, and Pico canyons, but not positively identified (English) ; lower Pliocene of Elsmere Canyon, locality 207, and of Holser Canyon, locality 2176, and middle Pliocene west of Fernando Pass, locality 214, Los Angeles County (H. R. G.). Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 349 Pleistocene: "Common in the upper San Pedro series of Los Cerritos," but rare at San Pedro; very abundant at Spanish Bight, San Diego (.^nold, 1903); Bay Point, near Pacific Beach, "few" (Stephens); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Monica (Wejonouth) to Gulf of Tehuantepec, Mexico. This well-known and handsome species is distinguished by its wliite shell and even, rounded, concentric riblets. It occurs on open beaches just below low tide, and is not often seen unless washed ashore by heavy seas. It occurs only as far north as Los Angeles County, where it is collected alive at Long Beach, Newport, Balboa, and other seaside communities. It may be quite sensitive to temperature conditions, for it is not present in the upper Pliocene and the cold-water Pleistocene faunas. There is a well-recognized variation in the shape of the valves, most specimens being elongate, while a few are quite rounded. The high form was named Dione nobilis Reeve. It is figured by Arnold (1907) from the Elsmere Pliocene. A very similar and certainly closely related species is known in the Tertiary of the Atlantic coast. The Atlantic and Pacific forms probably spUt from a common stock in the Miocene. Each is so variable in outline that it is probable that the variations overlap. Perhaps one should be recognized as a variety of the other. Also, the living florida (Lamarck) is barely distinguishable specifically. It has the hinge, shape, sculpture, lunule, and pallial sinus of callosa (according to specimens at the California Institute of Technology). Amiantis callosa (Conrad) variety stalderi (Clark) Plate 17, Figures 8a, 8& Pitana stalderi Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 468, pi. 53, figs. 5, 6, Aug. 30, 1915; Nomland, Vol. 10, pp. 301, 302, 1917. ; Antigona mUisi Trask, Univ. Calif. Publ. Geol., Vol. 13, p. 152, pi. 5, figs. 2a, 2b, May 10, 1922. Shell like that of the tjT^ical variety but with the anterior dorsal extremity descendmg more abruptly, changing the orientation of the shell, and making the beaks appear higher and more central; sculpture worn or weaker. Type specimens : In the University of California collection. Type localities: Of stalderi, San Pablo Bay, upper Miocene; of willisi, University of California locality 146, upper Miocene. Miocene: San Pablo and ? Briones formation, upper Miocene, of San Francisco Bay region (Clark; Trask); Santa Margarita formation, upper Miocene, of the Tejon Hills and north of Coalinga (Nomland) ; well core near Bakersfield, upper or possibly middle Miocene (H. R. G.). This variety will prove of value if the character of its outline is sufficiently constant to allow identification in the majority of cases. The sculpture is not trustworthy, as it is greatly affected by weathering. Amiantis dalli (Clark), also from the upper Miocene of middle California, has a much shorter end and maj^ average larger in size. "Antigona willisi" Trask may be a synonym; but the hinge is not visible in the type specimen, which is not well preserved. Amiantis dalli Clark Amiantis (Amiantis) dalli Clark, Univ. Calif. Publ. Geol., Vol. S, p. 465, pi. 50, fig. 2, pi. 53, figs. 1, 2, 3, 4, August 30, 1915. Pitaria behri Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 467, pi. 54, figs. 2, 3, 4, 1915. Amiantis communis Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 305, pi. 14, figs. 2a, 26, 2c, 2d, November 8, 1917. Shell unusually high, with almost circular shape; concentric sculpture somewhat irregular, affected by weathering; hinge coarse, irregular, apparently distorted. 350 San Diego Society of Natural History [Memoirs Type specimens: In the University of California collection. Type localities: Of dalli and behri, upper Miocene of San Francisco Bay region; of communis, upper Miocene northeast of Coalinga. Miocene: San Pablo group, upper Miocene, east of San Francisco Bay (Clark) ; Santa Margarita formation northeast of Coalinga (Nomland). This is an interesting and apparently quite distinct species. There seems to be but one form to take the three names. This form has a much higher and more circular shell than the Recent short specimens of A. callosa, which Reeve named Dione nobilis. From the Miocene beds of Kern River and Temblor, F. M. Anderson^ described "Venus iCallista) diabloensis," which is a high-beaked Amiantis, but not so extreme in shape as dalli. Subgenus HYSTEROCONCHA Fischer, 1887 Hysleroconcha Fischer, Man. Conchyl., p. 1079, 1887. Type (by monotypy), Venus dione Linnaeus; Recent, West Indies. Shell like that of the typical subgenus, but with a radial row of spines on the posterior part of the valves, and with the hinge teeth smaller, except the anterior right cardinal, which is larger; pallial sinus more rounded. Amiantis (Hysteroconcha) lupanaria (Lesson) Cytherea lupanaria Lesson, Centurie Zool., p. 196, pi. 64, 1830; Voy. Coquille, Zool., Vol. 2, Ft. 1, p. 4.30, 1830; Pfciffer, in Martini und Chemn. Conch. Cab., Ed. 2, Veneracea, p. 61, pi. 22, fig. 10, 1869. fide Lamy, 1909. Cytherea semilamellosa Gaudichaud, Delessert, Rec. Coq. Lamarck, pi. 19, fig. 2, 1841; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 520, 1864. Cytherea lupinaria Le.s.son, Sowerby, Thes. Conch., Vol. 2, p. 632, pi. 132, fig. HI, 1851. Dione lupanaria Lesson, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 67, 1857 Dione semilamellom Gaudichaud, Reeve, Conch. Icon., Vol. 14, Dione, pi. 6, figs. 20a, 20b, 1863. "Venus radiala Perry," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 520, 1864; not of Perry, Conch., pi. 58, Venus, fig. 2, "New Zealand," 1811. Pitaria (Hysteroconcha) lupanaria Lesson, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 388, 1902; Vol. 37, p. 267, 1909. Meretrix (Pitaria) lupanaria Lesson, Lamy, Journ. Conchyl., Vol. 57, p. 243, 1909. Pleistocene: Oaxaca, Mexico (R. H. Palmer, coll.). Recent: Ballenas Lagoon, Lower California, Mexico, to Paita, Peru (Dall, 1909). This is a handsome shell with long spines, like A. dione (Linnaeus), but larger. Genus DOSINIA Scopoli, 1777 Dosinia Scopoli, Intr. Hist. Nat., p. 399, 1777; Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 346, 1902; Trans. Wagner Inst. Sci., Vol. 3, p. 1226, 1903; Jukes-Browne, Proc. Malac. Soc. London, Vol. 10, p. 95, 1912; Vol. 11, p. 63, 1914; Palmer, Pala;o. Amer., Vol. 1, p. 268, 1927. Type (by monotypy), Chama dosin Adanson, Hist. Nat. Senegal, pi. 16, fig. 5, in text "Le Dosin," p. 225, 1757, "cote de Portudal," = Dosinia africana Hanley, figured by Palmer, Palaeo. Amer., Vol. 1, text fig. 6 of hinge, also pi. 48, figs. 5, 8, 13, 14, 1927- 1929; west coast of Africa, Recent. Shell of circular outline and low convexity, ranging from small to large and heavy; surface pol- ished, sculptured with somewhat distant, incised, concentric grooves; lunule impressed, escutcheon linear or obsolete; hinge plate rather broad, with a flat, platform-like area in each valve behind the teeth, in each valve just posterior to and under tlie beaks and anterior to the ligament a small area 1 Proc. Calif. Acad. Sci., Ser. 3 (Geol.), Vol. 2, p. 196, pi. 17, figs. 83-85, 1905. Volume 1 ) PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 351 excavated out of this platform, on the anterior edge of the platform in each valve a ridge set off so that it resembles a cardinal tooth, in the left valve anterior to this ridge two more cardinals, the pos- terior stout, the anterior thin (in the type widely diverging), and m addition a more or less well- developed anterior lateral, in the right valve three cardinals in front of the ridge, the posterior bifid, the anterior thin and close to the medial as in Pilar; pallial sinus distinct, V-shaped, generally strongly ascending; valve margins smooth. Geologic range: In North America, Eocene to Recent: in Europe, Miocene to Recent; in New Zealand, from Eocene (possibly Cretaceous) to Recent. For a discussion of the sections of this genus, the reader is referred to the literature cited above, particularly to the valuable papers by Jukes-Browne. The phylogenetic history of this genus promises to be very interesting when thor- oughly worked out. An example of the development of the hinge is noted below in the discussion of Dosinia ponderosa variety longidens. It appears to the present writers that the relationships between Dosinia and the other Venerids are much more significant than the differences, and that therefore it would be a mistake to separate this genus into a difi['erent subfamily. As has already been pointed out by Jukes-Browne or by Cossmann (the reference is not available at the present moment), Dosinia and Pilar (the latter in the past often called Callista) converge in the early Tertiary. If the VeneridcB are to be divided into subfamilies, Dosinia and Pilar should be placed together. However, Venus is not so far removed as the current practice of overemphasizing the distinction between the anterior cardinal tooth and the anterior lateral has led us to suppose. Because Dosinia has the shape more of Venus than of Pilar, it is easier to compare its hinge with that of Venus. The relation between Venus and Dosinia is similar to that between Clemenlia and Pilar. In the right valve the hinge elements are almost identical, except that in Dosinia and Pilar the anterior and middle cardinals are closer together than in Venus and Clemenlia. In the left valve the middle bifid cardinal of Venus, Paphia, Venerupis, and dementia has in Dosinia and Pilar apparently split more deeply, becoming two cardinals, and the anterior cardinal has swtmg around to a position parallel with the shell margin, becoming an anterior lateral. The difference has the appearance of being fundamental be- cause intergradations between the two arrangements are mechanically impossible. The ar- rangements involve a different order of interlocking of the anterior teeth. In the Venus ar- rangement, the most anterior tooth is in the right valve and in some cases is close to and parallel to the shell margin, like a lateral ; whereas, in the Dosinia arrangement, the middle cardinal of the right valve fits between the split parts of the middle cardinal of the left, and the anterior cardinal of the right valve takes its place behind the anterior tooth of the left, which is then free to swing around next to the shell margin. The change must therefore be made in one jump; and if this is true, different branches of the family may have made the same change independently. For the time being, until the phylogeny of the Veneridce is better known, it seems premature to divide the family into subfamilies on this basis. Dosinia ponderosa (Gray) Plate 15, Figures la, lb, Ic Arlemis ponderosa Gray, Analyst, Vol. 8, p. 309, 1838; Reeve, Conch. Icon., Vol. 6, Artemis, pi. 1, fig. 4, 1850; Sowerby, Thes. Conch., Vol. 2, p. 656, pi. 140, fig. 2, 1852. Cytherea {Artemis) gigantea Sowerby, Philippi, Abbild. Beschr. Conch., Vol. 2, Heft 8, Cytherea, p. 231, pi. 7, figs, la, 16, April, 1847, not Cytherea gigantea Gmelin, Sowerby, Thes. Conch., Vol. 2, p. 628, pi. 131, fig. 86. 1851. Venus cycloides d'Orbigny, Voy. Am^r. Merid., Moll., p. 562, 1847;^'de Lamy. ? Artemis distans Sowerby, Thes. Conch., Vol. 2, p. 657, pi. 140, fig. 3, 1851. 352 San Diego Society of Natural History [ Memoirs Dosinia ponderosa Gray, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 60, 1857; Gabb, Geol. Surv. Calif., Palaec, Vol. 2, p. 97, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 239, 1888, in part only; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 154, 1894; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 75, 1895; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 146, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 543, pi. 46, fig. 4, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Martin, Vol. 9, p. 252, 1916; Noni- land, Vol. 10, p. 299, 1917; Dall, Nautilus, Vol. 32, p. 24, 1918; U. S. Nat. Mus., Bull. 112, p. 41, 1921; Old- royd, Stanford Univ. Publ. Geol., Vol. 1, p. 149, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Dosinia {Dosinidia) ponderosa Gray, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 384, 1902. Shell large, heavy, more circular m outline than most species of Dosinia. Type specimen: In the British Museum. Type locality: Gulf of California. Variety ponderosa, s. s. Beaks rather low, lunule deeply impressed so that it makes nearly a right angle with the pro- truding anterior dorsal margin, no flattened area along the posterior dorsal margm; anterior lateral tooth of the left valve reduced to a small, rounded tubercle. Pleistocene: Upper Pleistocene at foot of Twenty-sixth Street, San Diego (Arnold; Stephens); upper Pleisto- cene of San Quintin Bay (Jordan), and Pleistocene of Magdalena Bay, Lower California, Mexico (Dall, 1918). Recent: San Diego, California, south to Paita, Peru (Dall, 1921). Although the characters of this variety (the typical) sound quite definite on paper, they are really not well defined, and it is difficult to classify specimens that depart from the typical form in one or more of the distinguishing characters. There is room for difference of opinion about the degree of distinction between the forms here considered. If each form did not vary so, it would be easier to decide whether it is a variety or a distinct species. The separation of the other varieties from ponderosa, s. s., recalls the separations made above between Venus elsmerensis and V. gnidia and between Amiantis callosa, s. s., and the variety stalderi. Dosinia ponderosa (Gray) variety jacalitosana Arnold Plate 15, Figures 2a, 2b, 3 Dosinia jacalitosana Arnold, U. S. Geol. Surv., Bull. 396, p. 67, pi. 16, fig. 5, January 15, 1910; Bull. 398, pi. 38, same figure, 1910; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 219, pi. 10, figs. 1, la, 1917; Hoots, Bull. 812-D, U. S. Geol. Surv., p. 284, 1930. Dosinia arnoldi Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 459, pi. 51, figs. 1, 2, Aug. 30, 1915; Nomland, Vol.10, pp. 300, 302, 1917. Dosinia (Dosinella) merriami Clark, Univ. Calif. Publ. Geol., Vol. 8, pp. 460, 461, pi. 49, figs. 1, 2, pi. 52, figs. 1, 2, Aug. 30, 1915. Shell like that of the typical variety but with more prominent beaks, a less impressed lunule, more descending anterior dorsal margin, and a beveled or flattened area along the posterior dorsal margin; anterior lateral tooth of the left valve larger and not regularly rounded- Type specimens: Of jacalitosana, in the U. S. National Museum, No. 165,575; of arnoldi and merriami, in the University of California collection. Type localities: Oi jacalitosana, fourteen miles southwest of Coalinga, lower Pliocene; of arnoldi, south side of Mount Diablo, upper San Pablo group, upper Miocene (also in Santa Margarita beds north of Coalinga); of merriami, Kirker's Pass to the north of Mt. Diablo, upper Miocene. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 353 Miocene: Base of San Pablo group at ICirker's Pass, north of Mt. Diablo, and lower San Pablo of San Pablo Bay, upper Miocene (Clark, as D. vierriami) ; upper San Pablo group, south side of Mt. Diablo, also Santa Margarita beds to the north of Coalinga (Clark, as arnoldi) ; Santa Margarita north of Coalinga, and questionably San Pablo of tlie Tejon Hills (Nomland, as arnoldi); Kirker's Pass, Contra Costa County (Cooper, as ponderosa); etc. Pliocene: Jaealitos of Coalinga region (Arnold; Nomland); Etchegoin of the southeastern end of the San Joaquin basin (Hoots); Dosinia beds of Balboa Park, San Diego (Hertlein and Grant); S. D. S. N. H. localities 228, 263, etc., between Pico Canyon and Fernando Pass, Los Angeles County, common; etc. A study of the variations of the Phocene Dosinia shows that the upper Miocene forms described by Clark as merriami and arnoldi fall well within the limits of variation of the Pliocene form. It is unfortunate that Arnold's type is poorly preserved, not showing the hinge, and worn so as to give an erroneous impression of its length. However, a recon- struction of its shape is a help, and Nomland has figured a better specimen from Arnold'.s locality. Nothing else is known that Arnold could have had. Weathering accounts for the appearance of the surface of merriami, sometimes producing the same effect on Plio- cene specimens. Dosinia ponderosa (Gray) variety occidentalis Clark Dosinia merriami variety occidentalis Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 462, pi. 50, fig. 1, 1915; Nomland, Vol. 10, p. 300, 1917. Dosinia merriami variety diabloensis Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 460, 1915, error for occidentalis. Shell like that of the variety jacalitosana, but with abnormally high beaks. Type specimen: In the University of California collection. Type locality: Presumably south s.de of Mount Diablo, upper Miocene. U. Miocene: Type locality (Clark; Nomland). This variety is a peculiar form. It recalls in shape Dosinia margaritana Wiedey' of the lower Miocene. Dosinia ponderosa (Gray) variety longidens, new variety Plate 15, Figure 4 ? Unnamed cast, Conrad, U. S. Pac. R. R. Survey, Reports, Vol. 5, pi. 4, fig. 32, 1856, reprinted by Blake, with ex- planation of plates indicating that the casts figured probably belong to Dosinia sp., New York, 1858. f "Dosinia ponderosa Gray," Arnold, U. S. Geol. Surv., Bull. 396, pp. 17, 21, 124, pi. 9, fig. 1, January 15, 1910; Bull. 398, pi. 31, same figure, 1910. Shell like that of the variety jaca/?'to.sar?a in shape but distinguished by the anterior lateral tooth of the left valve which is elongated parallel to the shell margin. Type specimen: No. 146 in the collection of the San Diego Society of Natural History. Type locality: Well core of the Superior Oil Company's well, Ansolabehere No. 1, in Sec. 9, T. 29 S., R. 27 E., Mt. Diablo Base and Meridian, northwest of Bakersfield; horizon, upper (possibly middle) Miocene. Miocene: Middle Miocene, Temblor formation, of Barker's Ranch, Kern County (specimen in the collection at Stanford University) ; ? Turritella bed on east flank of high hill northeast of Oil City, Coalinga district (Arnold, 1910, as D. ponderosa); at the type locality (see above; H. R. G.). One or more of a number of older names proposed by Conrad, Gabb, Wiedey, and possibly others may be apphcable to this form ; but as yet the hinge characters of these older-named forms are not known, and it is impossible to tell yet which, if any, of them ' Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 143, pi. 18, figs. 1, 2, March 31, 1928. 354 San Diego Society of Natural History [ Memoirs can be used here. Photographs of Conrad's three Miocene species are given on plate 22, figures 1, 3, 4. For the time being, therefore, the writers wish to call attention to the char- acter of the anterior lateral tooth by naming the variety longidens. The evolution of the anterior lateral tooth in Dosinia ponderosa is interesting. In the oldest variety, variety longidens, it is elongated like the anterior lateral of Pitar and other probably related genera. Except that it is more distant from the beaks, it is not unlike the right anterior cardinal of forms like Venerupis staminea variety ruderata (see plate 18, figure 3a). In the variety jacalitosana it has shrunk to a rounded mass; and in the living variety it has become a mere tubercle. Dosinia dunkeri (Philippi) Cytherea dunkeri Philippi, Abbild. Beschr. Conch., Vol. 1, Heft 7, Cytherea, p. 4, pi. 2, fig. 5, 1844. Cytherea pacifica M. Berol., fide Philippi, op. cil., not Venus pacifica Dillwyn, Descr. Cat. Rec. Shells, Vol. 1, pp. 175, 176, 1817 (= Venus chinensis Chemnitz, Neues Syst. Conch. Cab., Vol. 11, p. 227, pi. 202, fig. 1976, 1795, not Chemnitz, Vol. 10, p. 356, pi. 171, fig. 1663, 1788). ? Artemis simplex Hanley, Proc. Zool. Soc. London for 1845, p. 11, 1845; Cat. Rec. Biv. Shells, p. 357, pi. 15, fig. 41, 1842-56; Reeve, Conch. Icon., Vol. 6, Artemis, pi. 10, fig. 59, 1850; Sowerby, Thes. Conch., Vol. 2, p. 657, pi. 140, fig. 6, 1852. Artemis dunkeri Philippi, Reeve, Conch. Icon., Vol. 6, Artemis, pi. 6, fig. 41, 1850; Sowerby, Thes. Conch., Vol. 2, p. 657, pi. 140, fig. 5, 1852. Dosinia dunkeri Philippi, Carpenter, Cat. Reigcn Coll. Mazatlan Moll. Brit. Mus., p. 61, 1857; Romer, Monog. Dosinia, p. 17, pi. 3, fig. 3, 1862; Lamy, Journ. Conchyl., Vol. 57, p. 240, 1909; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 265, 1909; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 465, 1926. Dosinia {Dosinidia) dunkeri PhiUppi, Dall, Proc. U. S. Nat. Mus., Vol. 26, p. 384, 1902. Shell smaller than that of D. yonderosa, with higher, more prominent beaks. Pliocene: Imperial formation of Carrizo Creek region, western Imperial County (Hanna) . Recent: Gulf of California, Mexico, south to Tumbes, Peru, and the Galapagos Islands. The shape of this species recalls Dosinia mathewsonii Gabb, of the Miocene. The pallial sinus of dunkeri is strongly ascending, the lower margin being almost vertical. D. simplex appears to be based on a shell with a slightly higher umbo, but it is not suffi- ciently distinct to warrant a separate name. Dosinia hunkeri Hanna,' from the La Jolla Eocene, has a Ddsinoid shape, but a very thin shell and the hinge is unknown. It may not be a Dosinia. Dosinia ? alaskana Dall,- from the Tertiary beds of Popof Island, Alaska, is a high form that is questionably re- ferred to Dosinia, as the hinge is unknown. A number of other Pacific coast Tertiary Dosinias have been named, but need not be discussed here. Family PETRICOLIDAE Shell elongate to subglobose, variable in shape on account of the habit of boring in clay or soft rock; hinge narrow, generally with two cardinal teeth and posterior nymph; valves gaping at both ends; pallial sinus deep. Genus PETRICOLA Lamarck, 1801 Petricola Lamarck, Syst. Anim. s. Vert., p. 121, 1801; Children, Quart. Journ. Sci., Lit., and .\rts, p. 303, 1823; Gray, Proc. Zool. Soc. London for 1847, p. 184, 1847; Herrmannsen, Indicis Gen. Malac, Vol. 2, pp. 240-242, 1847; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 444, 1893; Jukes-Browne, Proc. Malac. Soc. London, Vol. 9, pp. 214, 215, 1910. IRupellaria Fleuriau de Bellevue, Journ. Physique, Vol. 54, p. 3, 1802. ' Univ. Calif. Publ. Geol.. Vol. 16. p. 287, pi. 42. figs. 4. 6, 1927. = Wash. Acad. Sci., Alaska, Res. Harriman Alaska Exped.. Vol. 4. p. 115, pi. 10. fig. 7, 1904, reissued b.v Smithsonian Inst., 1910, Deposits on north shore of Popof Island supposed to be of Miocene age. Volume 1 ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 355 Type (by subsequent designation, Gray, 1847), Venus lithophagus Retzius, M6m. Acad. Roy. Turin, Vol. 3, pp. 11-14, figs. 1, 2, 1786, + Rupellaria striata and R. reticulata F. de Bellevue, op. cit., p. 3, \802, fide Bucquoy, Dautzenberg, and Dollfus, op. cit., p. 445, pi. 67, figs. 20-28, 1893; also figured in Reeve, Conch. Icon., Vol. 19, Petricola, pi. 2, figs. 11a, lib, 1874; Mediterranean, and coasts of England, France and Spain. Petricola carditoides (Conrad) Plate 13, Figures 14o, 14b Saxicava carditoides Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 255, pi. 20, fig. 8, 1837. Saxicava californica Conrad, op. cit., p. 256, pi. 20, fig. 9, 1837. ? Petricola arcuata Deshayes, Rev. Zool. Soc. Couv., Vol. 2, p. 358, 1839, fide Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 835, 1898. ? Sa.ricava legumen Deshayes, Rev. Zool. Soc. Couv., Vol. 2, p. 358, 1S39, fide Dall, op. cit., p. 835, 1898. Saxicava abrupta Conrad, U. S. House of Representatives, Document No. 129, p. 13, July, 1855, reprinted by Dall, U. S. Geol. Surv., Prof. Paper 59, p. 166, 1909; Conrad, U. S. Pacific R. R. Repts., Vol. 5, p. 324, pi. 3, figs. 25, 25a, 1856. Petricola pedroana Conrad, U. S. House of Representatives, Document No. 129, p. 13, July, 1855, reprinted by Dall, op. cit., p. 166, 1909; Conrad, U. S. Pacific R. R. Repts., Vol. 5, p. 324, pi. 3, fig. 24, 1856. Petricola carditoides Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 526, 528, etc., 1864; reprinted in Smithsonian Miscellaneous Collections No. 252, 1872; Cooper, 7th Annual Rept. Calif. State Mineralogist, p. 258, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 154, 1903; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 124, 1909; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 220, 1917; Dall, U. S. Nat. Mus., BuU. 112, p. 44, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 163, pi. 34, figs. 6a, 6b, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 6, 1925; WaterfaU, Univ. Calif. Publ. Geol., Vol. IS, p. 78, 1929. Shell of medium size, extremely variable in shape, rather ventricose, varying from globular or short and subquadrate to elongate; umbones anterior, small, turned in and adjacent; valves gaping slightly at both ends; sculpture consisting of fine radiating threads and irregularly developed con- centric growi:h lines and lameUse; hinge with two oblique cardinal teeth in each valve, stronger on the right valve, the anterior cardinal of which is somewhat cuneiform and incipiently bipartite; ligament external, on a nymph posterior to the cardinal teeth; paUial sinus distinct, deep; adductor scars nearly equal in size. Dimensions quite variable : Elongate forms often about 35 mm. long and 17 mm. high; subquadrate forms about 35 mm. long and 28 mm. high. Type specimens: Of Saxicava abrupta Conrad, in the U. S. National Museum, No. 1,869; location of the others not known to the present authors. Type localities: Of S. carditoides, Santa Barbara, Recent; of S. californica, near Santa Barbara and San Diego; of S. abrupta and pedroana, San Pedro, Recent. Pliocene: Rare in Pecten coalingensis zone, upper Etchegoin formation, near CoaUnga (Nomland). Pleistocene: Lower San Pedro series at Deadman Island (Arnold); lower San Pedro of Nob Hill cut, "plenti- ful" (T. S. Oldroyd) ; "Saugus" formation near Ventura (WaterfaU) ; upper San Pedro series at Dead- man Island, Los Cerritos, Crawfish George's, and San Pedro; also Pleistocene at Spanish Bight, San Diego (Arnold). Recent: Vancouver Island, British Columbia, to Magdalena Bay, Lower California, Mexico (Dall, 1921). This species is exceedingly variable in shape because of its habit of living in holes in rocks or inside of dead shells. It varies from elongate to subovate, and occasional speci- mens are globular. The sculpture serves to distinguish it from denticulata Sowerby. P. carditoides has very fine, closely and rather evenly .spaced, radiating threads, while denticulata has larger, more widely spaced, and more continuous, radiating riblets, which increase in size and distance apart near the anterior end. Clark has described a Petricola from the upper Miocene, which should probably be referred here.' ^PeiricoUi buwaldi Clark. ITniv. Calif. Publ. Geol., Vol. 8. p. 471, pi. 60, fig. 6, 1915, based apparently upon a specimen that lived inside of a ribbed shell. 356 San Diego Society of Natural History [Memoirs Section Petricolaria Stoliczka, 1871 Petricolaria Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 139, 1871; Trj'on, Struct. Syst. Conch., Vol. 3, p. 174, pi. 112, fig. 94, 1884. Type (by subsequent designation, Tryon, 1884), P. pholadiformis Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 505, 1818, figured by Tryon, also by Reeve, Conch. Icon., Vol. 29, Petricola, pi. 1, fig. 7, 1874. Shell elongate, subcylindric anteriorly, laterally flattened posteriorly; sculpture of radial riblets coarser anteriorly; valves with slight gape at both ends. Geologic range: Tertiary to Recent. Distribution: Shores of North and South America; Ceylon; etc. The species belonging to this section are elongate, and the sculpture is generally coarser than on shells of the typical section. Petricolarias have stronger, larger, and wider-spaced ribs on the anterior portions of the valves, where the ribs are often frilled with growth lamellae. Petricola pholadiformis Lamarck Petricola pholadifoTmis Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 505, 1818; Deshayes and Milne Edwards Edition (Ed. 2), Vol. 6, p. 159, 1835; Reeve, Conch. Icon., Vol. 19, Petricola, pi. 1, fig. 7, 1874; Dall, U. S. Nat. Mus., Bull. 37, p. 58, pi. 59, fig. 15, pi. 64, fig. 140a, 1889. Petricola cogiiata C. B. Adams, Ann. New York Lye. Nat. Hist., Vol. 5, p. 510, 1852; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 363, 1857; Rept. for 1863, p. .552, 1864; Proc. Zool. Soc. London for 1863, p. 367, 1863. Petricola {Petricolaria) cognata C. B. Adams, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 156, 1903. Shell elongate, beaks near anterior end; sculpture of radiating ribs, very fine on posterior half of shell, coarse and widely spaced on anterior portion. Pleistoce?ie : Rare in the upper San Pedro series at the lumber yard at San Pedro and at Deadman Island (Arnold). Recent: North Atlantic (as P. pholadiformis) ; Panama and north, perhaps to California (generally as cognata). As there seems to be no significant difference between the Pacific and Atlantic speci- mens the older name is here used. There are specimens in the Stanford collection from Scammons Lagoon, Lower California, from Monterey, and from the mud-flats off Red- wood City in San Francisco Bay. The California specimens might have been introduced. Carpenter considered the Atlantic and Pacific forms identical. This species is more regularly elongate and has coarser anterior ribs than P denticu- lata. Petricola denticulata Sowerby Petricola denticulata Sowerby, Proc. Zool. Soc. London for 1834, p. 46, Sept., 1834; Thes. Conch., Vol. 2, Petricola, p. 773, pi. 166, figs. 6, 7, 1854; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 244, 297, 1857; Reeve, Conch. Icon., Vol. 19, Petricola, pi. 2, figs. 9a, 9b, Nov., 1874; Dall, Nautilus, Vol. 13, pp. 121, 122, 1900; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 163, 1924. Petricola tenuis Sowerby, 1834, C. B. Adams, and others, in part, fide Dall, 1900. Petricola nivea Sowerby, Proc. Zool. Soc. London for 1834, p. 34, 1834; Thes. Conch., Vol. 2, Petricola, p. 773, pi. 166, figs. 13, 14, 1854. Psephis tellimyalis Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 641, 1864; Journ. Conchyl., Vol. 12, p. 135, 1865, larval sheW, fide Dall, 1900.' 1 Since this went to press, Mr. George Willett of the Los Angeles Museum has shown the writers specimens of Petricola teUimyatis (Carpenter) and also young specimens of P. denticulata of the same size. It is clear that the two are distinct species. Carpenter's species is much more trigonal in shape than the young of denticulaia. It is also more brownish, and the largest specimens attain a length of only about a quarter of an inch. The type is in the U. S. National Museum. In 1S65 Carpenter said on the authority of J. Rowell, the col- lector, that it came from California. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 357 Cypricardia pedroana Conrad, Cooper, Calif. State Mining Bureau, BuU. 4, p. 25, 1894. Pelricola (Petricolaria) denticulala Sowerby, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 155, 1903. Pelricolaria denticidata Sowerby, Dall, U. S. Nat. Mus., Bull. 112, p. 44, 1921. Shell elongate, ventricose, with radial sculpture, the radial riblets larger and more widely spaced on the anterior portion of the valves. Type locality: Payta, Peru; Recent. Pliocene: In the city of Los Angeles (Williamson, fide Cooper). Pleistocene: "Rare in the upper San Pedro series at the lumber yard at San Pedro and at Deadman Island" (Arnold). The synonymy of this species is probably confused with that of carditoides. P. denticulata is variable in shape, but it can be distinguished from carditoides by its stronger, more continuous radial riblets. Superfamily Tellinacea Siphons distinct to their bases, usually long; pallial line sinuate; ligament external, seated on nymphs; hinge normally with an anterior and a posterior lateral in each valve, two radial cardinals, of which the anterior is usually bifid and somewhat pedunculated, and the posterior, as well as the laterals, often obsolete. (Dall.) Family TELLINIDAE Shell substance cellulo-crystalline, with an inconspicuous epidermis; valves slightly unequal, free, rounded in front, more or less rostrate, oblique and gaping behmd, compressed, usually with smooth margins, low beaks, and variable, chiefly concentric sculpture; anterior adductor scar larger, frequently irregular; pedal distinct; one or two isolated small scars made by attachments of the muscles of the mantle frequently visible near the ventral posterior termination of the pallial sinus; resilium embraced in the ligament, subexternal; cardinal area narrow, small, covered with a dark epidermis, or frequently obsolete ; hinge plate narrow, anterior lamina approximate, posterior more distant from the cardinals, when present; cardinal teeth small. (Dall.) Genus TELLINA Linnaeus, 1758 Tellina Linnaeus, Syst. Nat., Ed. 10, p. 674, 1758; Ed. 12, p. 1116, 1767; Gmelin, Syst. Nat., p. 3228, 1792; Children, Quart. Jour. Sci., Lit., and Arts, p. 306, January, 1823; Gray, Proc. Zool. Soc. London, Pt. 15, p. 186, 1847, StoUczka, Mem. Geol. Surv. India, Pal. Indiea, Vol. 3, p. 116, 1871; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 289, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1004, 1900; Woodring, Carnegie Inst., Publ. No. 366, p. 166, 1925. ? Anguliis Megerle von Miihlfeldt, Mag. Gesellsch. Naturf. Freunde zu Berlin, Vol. 5, p. 47, 1811. "TelUneUa Gray, 1852" Morch, Cat. Conch. Yoldi, Pt. 2, p. 13, 1853; H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 394, 1856; Stoliczka, Mem. Geol. Surv. India, Pal. Indiea, Vol. 3, p. 116, 1871. Eutellina Fischer, Man. de Conchyl., p. 1147, 1887. Liotellina Fischer, op. eit., p. 1147, 1887. Type (by subsequent designation. Children, 1823), Tellina radiata Linnaeus; Recent, West Indies. Shell elongate, of low convexity, posterior sometimes rostrated or twisted ; two lateral teeth in each valve; shell substance porcellanous. Geologic range: Jurassic to Recent. Distribution: World wide. The sections of this genus have not been critically revised. Section Tellina, s. s. Shell moderately large, with sculpture consisting primarily of growth lines ; posterior end some- what rostrated, with a shallow depression extending from near the posterior margin toward the umbo; right posterior and left anterior cardinals bifid; lateral laminae present, less prominent in the left valve; pallial sinus deep, U-shaped at end, lower margin confluent with pallial line. 358 San Diego Society of Natural History [Memoirs Tellina idae Dull Plate 20, Figures 12, 14a, 14b Tellina ida: Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 183, pi. 6, fig. 3, pi. 7, figs. 1, 4, 1891; Williamson, Vol. 15, p. 185, 1892; Cooper, Calif. State Mining Bureau, Bull. 4, p. 32, 1894; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 301, pi. 4, figs. 10, 11, 1900; Arnold, Vol. 32, p. 527, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Dall, Bull. 112, U. S. Nat. Mus., p. 45, 1921; Dall in Orcutt, West American Scientist, Vol. 19, No. 2, p. 19, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 164, pi. 14, fig. 4, 1924. Tellina (Angulus) idx Dall, Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 158, 159, pi. 15, fig. 6 (not fig. 7), 1903. Tellina nevadensis Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 61, pi. 2, figs. 32-c, 1914. ? Tellina englishi Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 472, pi. 61, figures 6, 7, 1915. Shell ovate-triangular ; posterior dorsal slope straight, obliquely truncate at the end, the posterior extremity rostrated by a narrow, shallow, radial depression just anterior to the rostral ridge; right valve with a deeply impressed line just in advance of the posterior dorsal margin; sculpture of definite, concentric, rather evenly spaced, fine incremental lamella. Type specimen: In the U. S. National Museum. Type locality: Long Beach, Los Angeles County; Recent. Miocene: "Lower Miocene" (probably Temblor) of Kern River and of San Luis Obispo County (Anderson and Martin, as nevadensis); San Pablo, upper Miocene (Clark, as englishi); (upper ?) Miocene of Superior Oil Company's well, Ansolabehere No. 1, near Bakersfield, depth 4575 feet (H. R. G.). Pliocene: Lower Fernando at Elsmere Canyon, Los Angeles County (Arnold, 1907; English, 1914) ; "Miocene" of San Diego (Dall, 1891); loc. 214 S. D. S. N. H., middle Pliocene west of Fernando Pass, Los Angeles County (H. R. G.). Pleistocene: Nob Hill cut, San Pedro, California (Oldroyd Collection at Stanford University); upper San Pedro series of Los Cerritos, Los Angeles County, very rare, "one valve" (Arnold, 1903); upper Pleistocene of San Quintin Bay, west coast of Lower CaUfornia, Mexico (Dall in Orcutt, 1921). Recent: Santa Barbara Islands, Catalina, and San Pedro, California. Tellina nevadensis Anderson and Martin, from the "lower Miocene" (probably Temblor) of Kern River and of San Luis Obispo County, appears to be of the same species as specimens of T. idee from Nob Hill, San Pedro, in the Oldroyd Collection at Stanford University. T. englishi Clark is considerably more elongate, but variations in specimens show that this feature is probably without significance. This very distinct species is not at all common. The concentric lines are stronger, sharper, and more distant on the right valve than on the left. Tellina aragonia Dall Tellina aragonia Dall, Prof. Paper 59, U. S. Geol. Surv., pp. 18, 124, 125, pi. 14, fig. 3, 1909; Arnold, U. S. Geol. Surv., Bull. 396, pp. 26, 134, pi. 14, fig. 2, Jan. 15, 1910; Bull. 398, pi. 36, same figure, 1910; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922. Type specimen : In the U. S. National Museum, Catalogue No. 153,940. Type locality: Coos Bay, Oregon; upper Miocene. Miocene: Empire formation, Coos Bay, Oregon (Dall; Howe). Pliocene: Jacalitos formation, Coalinga district, California (Arnold). This species is well figured by Arnold. It appears to be closely related to Tellina santarosce Dall,^ a Recent species of a slightly more elongate shape. It is broadly and bluntly rostrated, the posterior dorsal margin being curved, not straight as in T. idee. It may not belong to this section. ' Proc. U. S. Nat. Mus., Vol. 23, p. 321, pi. 3, fig. 6, pi. 4, figs. 1, 2, 1900. Volume I ] PlIOCENE AND PLEISTOCENE MoLLXJSCA OF CALIFORNIA 359 Section Moerella Fischer, 1887 Moerella Fischer, Man. de Conchyl., p. 1147, 1887; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 291, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1014, 1900; Woodring, Carnegie Inst., Publ. No. 366, p. 166, 1925. Type (by monotypy), TeJlina donacina Linnaeus; Recent, seas of Europe. Shell medium-sized, inflated, elongate-ovate, inequilateral, posterior end obscurely rostrate; sculpture consisting of concentric rugae ; right anterior and left posterior cardinals veiy small ; right laterals strong, anterior one closer to cardinals ; left laterals weaker, anterior one weaker than pos- terior; pallial sinus almost touching anterior adductor scar, confluent with pallial line, its apex U- shaped. (Woodring.) Moerella is close to Tellina, s. s., but has a weaker left anterior lateral tooth and the rostration is more obscure. According to Dall, Moera Adams, 1856, not Leach, 1815; Mcera Adams, 1856, not Leach, 1813: and Donacilla Gray, 1851, not Lamarck, 1812, are synonyms. Tellina salmonea (Carpenter) Miera salmonea Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 639, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 14, p. 423, 1864. Tellina (Moerella) salmonea Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 302, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 157, pi. 13, fig. 7, 1903; Dall, Bull. 112, V. S. Nat. Mus., p. 45, 1921; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 1, p. 165, pi. 44, figs. 3a-6, 1924; T .S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 6, 1925. Tellina salmonea Carpenter, Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 420, 1915. Type locality: Vancouver Island, British Columbia; Recent. Miocene: Upper and lower parts of the San Pablo formation, middle California (Clark). Pleistocene: Lower San Pedro series of Deadman Island, "not uncommon'' (Arnold); lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd). Recent: Aleutian Islands to San Pedro, California (DaU, 1921). Tellina meropsis Dall Plate 14, Figures 9a, 9b; Plate 20, Figures 9a, 9b "Tellina gouldi Hanley" of Carpenter and of some Pacific coast coUectors; not of Hanley. Tellina {Moerella) tneropsis Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 317, pi. 3, fig. 1, November, 1900; Bull. 112, U. S. Nat. Mus., p. 45, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 166, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Tellina meropsis DaU, Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, no. 16, pp. 250, 253, 1929. Type specimen: In the TJ. S. National Museum, Cat. No. 123,410. Type locality: San Diego, California; Recent. Pleistocene: "Saugus" formation, near Ventura (Waterfall); near International Boundary Monument No. 258, also at northeast corner of Mission Bay, San Diego County (Frank Stephens). Recent: San Diego, California, to the Gulf of California, Mexico (Dall, 1921). Specimens in the Oldroyd Collection at Stanford University labeled Tellina meropsis Dall appear to be the same as other shells labeled T. reclusa Dall. We have not seen the type specimens of either species and retain them with misgivings in the separate sections where they were placed by their author. Section Merisca Dall, 1900 Mensca Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 290, November 14, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1012, December, 1900; Woodring, Carnegie Inst., Publ. No. 366, p. 171, 1925. Type (by original designation), Tellina crystallina Wood, General Conch., p. 149, 1815; Recent, West Indies and Pacific coast of Central America; figured by Dall, Proc. U. S. Nat. Mus., Vol. 23, pp. 311, 312, pi. 2, fig. 10, 1900. 360 San Diego Society of Natural History [ Memoirs Shell small or of moderate size, trigonal-ovate, moderately convex, posterior end rostrated, with basal margin emarginate in front of rostrum; sculpture consisting of distant, thin concentric lamellse and sometimes fine radial lines ; pallial sinus deep, confluent with pallial line; hmge with strong later- als in the right valve, but without laterals in the left valve. The strong right lateral teeth and the absence of left laterals distinguish this section from Tellina, s. s. Tellina reclusa Dall Tellina (Merisca) reclusa Dall, Proc. U. S. Nat. INIus., Vol. 23, p. 315, pi. 3, fig. 2, 1900; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924. Type specimen: In the U. S. National Museum, Cat. No. 105,513. Type locality: San Ignacio Lagoon, Lower California, Mexico; Recent. Pleistocene: Upper Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: San Ignacio Lagoon, west coast of Lower California, to Gulf of California, Mexico (DaD). This species resembles T. meropsis, but appears to have a posterior sulcus on the left valve which is lacking or obscure on the left valve of meropsis. Dall figures opposite valves of the two species. Section Eurytellina Fischer, 1887 Eurytellina Fischer, Man. Conchyl., p. 1147, 1887; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 290, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1013, 1900; Woodring, Carnegie Inst., Publ. No. 366, pp. 167, 168, 1925. Type (by monotypy), Tellina punicea Born, Testacea Musei Csesarei Vindobonensis, p. 33, pi. 2, fig. 8, 1780; Recent, Pacific coast of northern South America. Shell medium-sized, elongate-ovate, subequilateral ; posterior end not rostrate but with a narrow flattened area; sculpture consisting of concentric rugae; right anterior cardinal relatively heavy, right laterals strong, anterior lateral close to the cardinals, posterior lateral distant; left posterior cardinal small and very slender, left laterals not so strong as the right, resembling them in position; pallial sinus touching anterior adductor, wholly confluent with pallial line. (Woodring.) The lack of rostration and the characters of the hinge are sufficient to distinguish this section from the other groups of this genus. According to Woodring, it is extensively represented in Tertiary and Recent faunas. Tellina rubescens Hanley Tellina rubescens Hanley, Proc. Zool. Soc. London for 1844, p. 60, 1844; Sowerby, Thes. Conch., Vol. 1, Tellina, p. 242, pi. 50, fig. 153, 1846; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 270, 1909; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Tellina sim.ulans C. B. Adams, Ann. Lye. Nat. Hist. N. Y., Vol. 5, p. 508, 1852; Romer, in Martini und Chemnitz, Conch. Cab., Ed. 2, Tellinida?, p. 99, pi. 25, figs. 4, 5, 1871; Bertin, Nouv. Arehiv. Mus. Paris, Ser. 2, Vol. 1, p. 259, 1878. "Tellina punicea Born," Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 35, 1857, not of von Born, 1780; Reeve, Conch. Icon., Vol. 17, Tellina, pi. 12, fig. 53, 1866; ^^e Lamy, 1909. Tellina {Eurytellina) rubescens Hanley, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 302, 1900; Lamy, Journ. de Conchyl., Vol. 57, p. 251, 1909. Tellina (Angulus) rubescens Hanley, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 159, pi. 15, fig. 8 (not fig. 9 as given), 1903. Pleistocene: Lower Quaternary of Magdalena Bay, west coast of Lower California, Mexico (Jordan); "rare in upper San Pedro series of San Pedro" (Arnold). Recent: Scammons Lagoon, Lower California, Mexico, to Tumbez, Peru. This species has very little evidence of posterior rostration, the anterior and posterior margins being greatly dissimilar in general aspect. It reaches a length of 40 or 50 milli- meters. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 361 Tellina oregonensis Conrad,' from the Miocene of Oregon and Washington, may belong to this section. Some of its supposed occurrences may be of OUgocene age. Section Angulus Megerle, 1811 Angulus Megerle von Miihlfeldt, Mag. GeseUsch. Naturf. Freunde zu Berlin, Vol. 5, p. 47, ISll; Gray, Proc. Zool. Soc. London, Pt. 15, p. 186, 1847; Dall, Proc. II. S. Nat. Mus., Vol. 23, p. 291, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1014, 1900. Type (by subsequent designation, Gray, 1847), Tellina lanceolata Linnaeus. Size generally small, elongate, posterior end pointed but not twisted, sculptured with fine concen- tric lamellse or normal growth lines, or smooth; hinge with a single strong right anterior lateral tooth, which is closely adjacent to the cardinals, other laterals absent. Geologic range: Eocene to Recent (Dall, 1900). Tellina carpenteri Dall Angulus variegatus Carpenter, Brit. Assn. Adv. Sci., Report for 1863, pp. 611, 627, 639, 1864; .\nn. Mag. Nat. Hist., Ser. 3, Vol. 14, pp. 423, 424, Dee., 1864; not Tellina variegata Gmelin, 1792. TelliHa (Angulus) carpenteri Dall, Proc. U. S. Nat. Mu.s., Vol. 23, p. 303, 1900; Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 421, 1908; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 1, p. 166, pi. 44, figs. lOa-b, pi. 29, fig. 2, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, .\rt. 22, p. 7, 1925. Tellina carpenteri Dall, Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 276, pi. 25, fig. 10, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type locality: Neah Bay; Recent. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd); lower Quaternary of Mag- dalena Bay, Lower California (Jordan, 1924); upper Pleistocene of San Quintin Bay, Lower Cali- fornia, Me.xico (Jordan, 1926). Recent: Forrester Island, Alaska, to Gulf of California, Mexico (Dall, 1921) ; Panama (Dall, 1908). Tellina modesta (Carpenter) Angulus modeslus Carpenter, Brit. Assn. .^dv. Sci., Kept, for 1863, pp. 602, 639, 681, 1864; Proc. Acad. Nat. Sci. Phila. for 1865, p. 54; Dall, Bull. 112, U. S. Nat. Mus., p. 45, 1921. Tellina (Angulus) modesta Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 304, 1900; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 167, 1924. Telli7ia modesta Carpenter, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924. Pleistocene: Upper Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Vancouver Island, British Columbia, to Lower California, Mexico (Dall, 1921). Section Oudardia Monterosato, 1884 Oudardia Monterosato, Nomencl. Gen. Spec. Conch. Medit., p. 22, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 291, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1014, 1900. Type (by original designation), Tellina oudardii Payraudeau, Cat. Annel. Moll. I'lle de Corse, p. 40, pl. 1, figs 16-18, 1826 = Tellina compressa Brocchi, Conch, foss. Subapp., p. 514, pl. 12, fig. 9, 1814, ^rfe Monterosato, 1884. With a thick internal anterior rib. (Dall.) Tellina buttoni Dall .' Tellina pedroana Conrad, U. S. Pacific R. R. Repts., Vol. 5, p. 323, pl. 3, fig. 17, 1855. I Macoma pedroana Conrad, Gabb, Geol. Surv. Calif., Palseo., Vol. 2, pp. 94, 124, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 248, 1888. Angulus ? var. ohtusus Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864, not Tellina ohtusa Sowerby, Min. Conch., Vol. 2, p. 175, pl. 179, fig. 4, 1818. ■ Amer. Jour. Sei., Ser. 2, Vol. 5, p. 432, fig. 5, 1848, reproduced by Dall, Prof. Paper 59 U. S. Geol. Surv., p. 150, fig. 5, 1909. 362 San Diego Society of Natural History [Memoirs Tellina (Angulus) var. obtusus Carpenter, Proc. Acad. Nat. Sci. Phila., p. 56, 1865, not Tellina oblusa Sowerby, 1818. "Angvlvs modeslus Carpenter" of some early California collectors, not of Carpenter, 1864. Tellina {Oudardia) hutloni Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 304, pi. 4, figs. 12, 13, November 14, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1036, pi. 47, fig. 18, December, 1900; U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 167, pi. 44, figs. 7o-b, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Tellina (Angulus) hutloni Dall, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 157, pi. 15, figs. 2 and 9, 1903, not pi. 16, figs. 1 and 2. Tellina hutloni Dall, Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 252, 1929. Type specimen: In the U. S. National Museum, No. 42,865a. Type locality: Guadalupe Island, Lower California, Mexico; Recent. Pleistocene: Lower San Pedro of Deadman Island and San Pedro bluffs (Arnold); lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd); Pleistocene at Barlow's Ranch, near Ventura (Arnold); "Saugus" near Ventura (Waterfall); Pleistocene of San Diego (Dall, 1900); Pleistocene of Spanish Bight, San Diego (Stephens) ; upper San Pedro of Deadman Island, San Pedro, Crawfish George's, and Los Cerritos (Arnold); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Lituya Bay, Alaska, to the Gulf of California, Me.xico (Dall, 1921). Section Peronidia Dall, 1900 Peronidia Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 291, November 14, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1014, December, 1900. Type (by original designation), Tellina albicans Gmelin. Shell writhout laterals, having the internal characters oi Angulug, s. s., and the external characters of Eurytellina Fischer. (Dall.) Tellina bodegensis Hinds Plate 20, Figure 13 Tellina hodegensis Hinds, Zoology Voy. Sulphur, Mollusca, p. 67, pi. 21, fig. 2, 1844; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 267, 1888; Keep, West Coast Shells, p. 197, fig. 169, 1888, 1892; Wilhamson, Proc. U. S. Nat. Mus., Vol. 15, p. 185, 1892; Dall, Vol. 23, p. 320, pi. 4, figs. 12, 13, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1029, 1900; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 254, 1916; Nomland, Vol. 10, table opp. p. 230, 1917; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 42, pi. 11, fig. 1, 1920; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 251, 1929. Tellina (Angulus) hodegensis Hinds, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 158, pi. 15, fig. 7 (not fig. 8), 1903. Tellina (Peronidia) bodegensis Hinds, DaU, Proc. U. S. Nat. Mus., Vol. 23, p. 304, 1900; U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 168, pi. 44, fig. 5, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type locality: Bodegas Bay, California; Recent. f Miocene: Oregon; Walnut Creek, Contra Costa County (Cooper). Pliocene: Etchegoin formation, Chione elsmere7isis zone, of Coalinga region (Nomland); lower Merced forma- tion near San Francisco, and middle Wildcat formation of northern California (Martin). Pleistocene: San Pedro to San Diego (Cooper); lower San Pedro series of Deadman Island and San Pedro; Pleistocene at Spanish Bight, San Diego (Arnold); lower San Pedro fauna of Nob Hill cut at San Pedro (T. S. Oldroyd), "Saugus" formation near Ventura (Waterfall); near International Boundary Monument No. 258, San Diego County (Stephens); lower Quaternary of Magdalena Bay, Lower California, Mexico (Jordan, 1924); upper San Pedro series at San Pedro, Los Cerritos, Crawfish George's, Deadman Island, and Long Beach, common (Arnold) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Queen Charlotte Islands, British Columbia, to Gulf of California, Mexico; questionably Japan (Dall, 1921). Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 363 Tellina lutea Gray Tellinalutea Gray, Index Testae, Suppl., pi. 1, fig. 3c, IS2S, fide Dall, 1900; Grewingk, Russisch-Kaiserliche Mineralo- gische Gesell. zu St.-Petersburg, Verhandlungen for the years 1848 and 1849, p. 359, 18.50; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1856, pp. 219, 221, 301, 1857; Kept, for 1863, p. 9, 1864; not "Tellina lutea Gray," Krause, Archiv. f. Naturg. for 1885, p. 37. Tellina alternidentala Broderip and Sowerby, Zool. Journ., Vol. 4, pt. 15, p. 363, 1829 (possibly October, 1828); Sowerby, Zool. Voy. Blossom (Captain Beechey's Voy.), p. 153, pi. 44, fig. 5, 1839; Dall, U. S. Geol. Surv., 17th Ann. Kept., Pt. 1, p. 845, 1896. Tellina guildfordix Gray, in Griffith's Cuvier, Vol. 12, pi. 19, fig. 2, 1834., fide Dall, 1900. ? Tellina venulosa Schrenck, Bull. Acad. Imp. Sci., p. 411, 1861; Reise in Amurl., Moll., p. 556, pi. 22, figs. 2-5, 1867, fide DaU, 1900. Tellina (Peronidia) lutea Gray, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 322, pi. 4, figs. 15, 16, 1900; Dall, Wash. Acad. Sci., Alaska, Res. Harriraan Alaska Exped., Vol. 4, p. 116, 1904, reissued by Smithsonian Inst., 1910; Dall, U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 169, pi. 1, fig. 9, 1924. Type locality: Icy Cape, Arctic Ocean. Miocene: "Tertiary" of Alaksa, Unga, Unalaschka, St. Paul (?), Atcha (?), (Grewingk); Miocene of St. Paul Island, Atka Island, Unalaska, Morzhowi, Unga Island (Dall, 1896, as T. alternidentata B. & S.). Recent: Arctic Ocean, Bering Sea, north Japan, the Aleutian Islands and east to Cooks Inlet, Alaska (Dall, 1921). DaU in 1921 concluded that T. venulosa Schrenck was a valid variety of lutea Gray. In 1904 he questioned Grewingk's identification of T. lutea from the Alaskan Tertiary. Genus APOLYMETIS Salisbury, 1929 Capsa sp., Bruguiere, Encycl. Meth., Vol. 1, pi. 231, figs, la-c, 1797, not the type. Caysa Lamarck, M6m. Soc. Hist. Nat. Paris, Vol. 1, p. 84, 1799; not Capsa Humphrey, 1797, nor of Lamarck, Syst. Nouv. Class., p. 126, 1801, nor of Lamarck, Anim. s. Vert., Vol. 5, p. .553, 1818, fide Dall, December, 1900. Cas-pa Bosc, Hist. Nat. Coq., p. 18, 1802, err. pro Capsa. Metis H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 399, November, 1856, not of H. and A. Adams, op. cit., p. 436, March, 1857, = Myrsus H. and A. Adams, corrigenda, p. 660, November, 1858; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 292, November, 1900; Trans. Wagner Inst. Sci., Vol. 3, pp. 1039-1041, December, 1900: not Metis Philippi, Archiv. f. Naturg., Vol. 9, p. 59, 1843; nor Metis Gistel, Naturg. Thierr. f. Hoh. Schul., p. 174, 1848. "Lutricola Blainville," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864, not of Blainville, Man. Malac, Vol. 1, p. 566, 1825. Polymetis A. E. Salisbury, Proc. Malac. Soc. London, Vol. 18, p. 255, July 15, 1929, new name for Metis; not Polymetis Walsingham, 1903. Apolymetis Salisbury, Proc. Malac. Soc. London, Vol. 18, p. 258, Nov., 1929, new name for Polymetis. Type (by monotypy), "Tellina meyeri 'Phil" = Tellina meyeri Dunker, ^de Philippi, Abbild. Beschreib, Conchyl., Vol. 2, Tellina, p. 89, pi. 4, fig. 1, Aug., 1846; East Indies. Shell sub-orbicular, compressed, surface of valves sulcate ; hinder flexuosity sub-median. Lateral teeth wanting. (H. and A. Adams.) It is unfortunate that Schmidt's designation makes Venus deflorata Linnaeus (figured by Bruguiere, pi. 231, figs. 3a, 35) the type of Capsa\ for thus Capsa becomes a synonym of Asaphis Modeer, 1793. Bruguiere's first species is much like our Apolymetis. Asaphis is a finely, radially striate genus quite different from Apolymetis. Apolymetis biangulata (Carpenter) Plate 20, Figure 16 Tellina alia Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 258, 1837; Hanley in Sowerby, Thes. Conch., Vol. 1, p. 332, pi. 62, fig. 200, 1847; not Tellina alta Conrad, Fossil Shells of the Tertiary Formations of North America, Vol. 1, no. 4, p. 41, Phila., 1833. ■ Fide Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 285, 1930. 364 San Diego Society of Natural History [Memoirs Scrohiailaria biangidala Carpenter, Proc. Zool. Soe. London, Pt. 23, pp. 213, 230, 1855; Brit. As.sn. Adv. Sci., Rept. for 1856, p. 195, 1857. Arcopagia medialis Conrad, Proc. Acad. Nat. Sci. Phila., VoL 8, p. 314, December, 1856; IT. S. Pac. R. R. Reports, VoL 6, Pt. 2, p. 70, pi. 2, fig. 6, 1857; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 174, 1909, reprint of Conrad, 1856. Scrobicitlaria biangularis Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 303, 1857, err. pro binngulata. ? Arcopagia iinda Conrad, U. S. Pacific R. R. Repts., Vol. 7, p. 192, pi. 4, figs. 3, 4, 1857; type specimen. No. 13,328, U. S. Nat. Mus. Lulricola alia Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864; Journ. de Conchyl., Vol. 12, p. 133, 1865; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 247, 1888; Keep, West Coast Shells, p. 197, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 186, 1892. Metis aha Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 306, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1044, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 160, 1903; U. S. Geol. Surv., Bull. 309, pp. 24, 26, 107, 1907; Bull. 396, pp. 17, 24, 25, 118, pi. 6, fig. 1, Jan. 15, 1910; Bull. 398, pi. 28, same figure, 1910; Kew Univ. Calif. Publ. Geol., Vol. 8, p. 46, 1914; English, Vol. 8, p. 210, 1914; Clark, Vol. 8, p. 418, 1915; Nomland, Vol. 10, pp. 211, 219, 300-304, 1917; Dall, Nautilus, Vol. 32, p. 24, 1918; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 42, pi. 11, fig. 2, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 169, pi. 57, fig. 3, 1924; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Miocene: Vaqueros formation, Coalinga region, specific identity questioned (Arnold, 1910); Monterey County (Conrad, 1856, 1857, as Arcopagia nwdialis); El Toro Ranch, Monterey County (Cooper); upper and lower San Pablo and Santa Margarita formations, upper Miocene, middle California (Clark, 1915) ; Vaqueros-Temblor, lower and middle Miocene of middle California; Santa Margarita formation, upper Miocene, north of Coalinga, in the Tejon Hills, at the type section, and on Naci- miento River (Nomland, 1917). Pliocene: Lower Pliocene of Elsmere and Holser canyons (English) and of various localities in eastern Ventura basin, southern California (Cooper; Arnold; etc.); Jacalitos and Etchegoin formations (Clark; Nomland); lower division of Carrizo formation. Imperial County (Kew); Pliocene of Pacific Beach, San Diego (Arnold, 1903); upper Pliocene at Santa Barbara (Cooper; Arnold). Pleistocene: Lower San Pedro series at Deadman Island (Arnold, 1903); lower San Pedro of Nob Hill (Oldroyd); "upper Fernando" near mouth of Adams Canyon, Ventura County (Arnold, 1907); Spanish Bight, San Diego (Arnold, 1903); Pleistocene of San Diego (Dall, 1900, Wagner Inst.); lower Quaternarj' at Magdalena Bay, Lower California, Mexico (Jordan); upper San Pedro forma- tion (= Palos Verdes formation) of San Pedro, very common at Los Cerritos, less common at Deadman Island and Crawfish George's (Arnold); Pleistocene of Magdalena Bay (Dall, 1918), and upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Santa Barbara to San Diego, California. As the Pacific coast species commonly known as Metis alia was originally described in 1837 as Tellina alta, its name is preoccupied by the prior Tellina alia of Conrad, 1833, and can no longer be used. The Tellina alta, 1833, is an entirely different species. The next available name appears to be hiangulaia Carpenter, 1855; but T. turgida and obesa Deshayes, 1854, should be compared when the literature and specimens are available. Arcopagia medialis Conrad appears to be a synonym, but A. unda, judging only from Conrad's figures, is much less certainly identical and may possibly belong to a different genus. Apolymetis excavata (Sowerby) Tellina excavata Sowerby, Reeve's Conch. Icon., Vol. 17, Tellina, pi. 26, fig. 138, 1867. Metis excavata Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 271, 1909; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 467, pi. 23, fig. 6, 1926; Hanna and Hertlein, Vol.' 16, p. 141, 1927. Pliocene: Coyote Mountain, western Imperial County (Hanna); Loreto, Lower California, Mexico (Hanna and Hertlein). Recent: Gulf of California, Mexico, South to Peru and the Galapagos Islands (Dall, 1909). This species is the southern representative of Apolymetis hiangulaia (Carpenter). Volume I ] PlIOCENB AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 365 Genus MACOMA Leach, 1819 Limicola Leach, Moll. Gt. Brit., p. 296, 1816; not Limicola Koch, 1S16, nor Fischer, 1887. Macoma Leach, in Ross's Voy. of Discovery in H. M. S. Isabella and Alexander, Appendix 2, p. l.vii, 1819; Journ. de Physique, Vol. 88, p. 465, 1819; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 292, 1900; Trans. Wagner Inst. Sci., Vol. 3, pp. 1044, 1045, 1900; Woodring, Carnegie Inst., Publ. No. 366, p. 176, 1925. ••MacToma Leach," Gray, Ann. Phil., Vol. 25, p. 136, 1825; Proc. Zool. Soc. London, Pt. 15, p. 186, 1847, err. pro Macoma. "PsammoUa Turton," Gray, Proc. Zool. Soc. London, Pt. 15, p. 186, 1847, not of Turton, 1822, nor Lamarck, fide Dall, 1900. Type (by monotypy), Macoma tenera Leach, = Tellina calcarea Gmelin, North American and boreal seas, to Japan and Port Etches, Alaska, in the Pacific, and to Long Island Sound, in the Atlantic. Shell without lateral teeth; of a rounded subtrigonal shape, usually but slightly inflated, generally with a marked posterior flexure; sculpture lacking or of feeble concentric growth lines; pallial sinus generally confluent with the pallial Ime. Geologic range: Tertiary to Recent. Distribution: Widespread, generally cooler seas. A number of subgeneric and sectional names have been used for minor subdivisions of Macoma, but they will not be considered in this paper. For a discussion of some of these subdivisions the reader may consult the two papers by Dall (1900) referred to above. A preliminary study of the Quaternary Pacific coast Macomas suggests that over- naming has occurred. Lacking specific types to study at first hand, we have in most cases accepted the status as given by Dall in 1921. Macoma nasuta (Conrad) Plate 20, Figures 11a, 116 Tellina nasuta Conrad, Jour. Acad. Nat. Sci. Phila., Ser. 1, p. 258, 1837; Hanley, in Sowerby's Thes. Conch., Vol. 1, Tellina, p. 314, pi. 64, fig. 224, 1846; not Tellina nasuta Conrad, U. S. Exploring Exped., Vol. 12, p. 725, 1849 (= T. subnasuta Conrad, 1865). Macoma nasuta Conrad, Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 93, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 248, 1888; Keep, West Coast Shells, p. 194, fig. 165, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 185, 1892; Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896; Proc. U. S. Nat. Mus., Vol. 23, pp. 307, 308, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1053, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 163, pi. 16, fig. 3, 1903; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 127, 1909; Arnold, U. S. Geol. Surv., Bull. 396, p. 156, pi. 25, fig. 5, Jan. 15, 1910; Arnold and Anderson, Bull. 398, p. 318, pi. 42, fig. 6, p. 328, pi. 47, fig. 5, 1910; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 593, 594, 596, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 418, 1915; Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, pp. 28, 32, 1916; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 252, 1916; Nomland, Vol. 10, pp. 219, 300, 1917; Packard, Univ. Calif, Publ. Zool,, Vol. 14, p. 279, pi. 23, figs, la-d, 1918; Weymouth, Calif. Fish and Game Comm., Fi,sh Bull. No. 4, p. 43, pi. 11, fig. 3, pi. 12, figs. 1, 2, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 47, 1921; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, pp. 550, 563, 1922; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 53, pi. 32, figs, la. Id, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 174, pi. 45, figs, la-d (reproduction of Packard's figures), 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Shell of moderate to large size, compressed, subtrigonal in outline, beaks usually a little nearer the anterior extremity, anterior dorsal margin roimcling smoothly into the broader curve of the ven- tral margm, posterior dorsal margm descendmg in a nearly straight line to the narrow, truncated posterior extremity, posterior extremity flexed to the right; sculpture of inconspicuous growth lines only; hinge strong and wide for a species of this genus. Dimensions (accordmg to Conrad, 1837): Length, IJ^ inches; height, IJ^. Type specimen: At the Academy of Natural Sciences, Philadelphia. Type locality: Near San Diego, California; Recent. 366 San Diego Society of Natural History [Memoirs 1 0ligocenc: Oligocene (?) sandstones at Miller's Beach, Coos Bay, Oregon (Dall, 1909). Miocene: Lower Miocene on the Strait of Juan de Fuca, Clallam County, Washington; Montesano formation and upper Miocene of western Washington (Weaver) ; Vaqueros formation of California (Nomland) ; San Pablo formation, upper Miocene of middle California (Clark; Martin); Empire formation of Coos Bay region, Oregon (Dall); Miocene at Sunol, Alameda County, and of Foxin's Ranch, Santa Barbara County (Cooper); Miocene of Nushagak, Alaska, and of British Columbia (Dall, 1896); Santa Margarita formation, upper Miocene, north of Coalinga (Nomland). Pliocene: Eagle Prairie and Danger Creek, Humboldt County ; Santa Rosa ; San Fernando (Cooper) ; lower and upper Wildcat, Pliocene of northern California (Martin; Howe); Merced and Purisima formations of the region south of San Francisco (Dall, 1909; Martin); region near Petaluma (Dickerson); Etchegoin of Sargent oil field and of the Coalinga region (Martin; Nomland); Jacalitos and Etche- goin formations (Arnold ; Clark) ; lower Fernando of Holser Canyon, Los Angeles County (English) ; middle Pliocene of Santa Clara Valley region, Los Angeles County (coll. by Gale); middle Pliocene of Pacific Beach, San Diego (Arnold, 1903); Pico near Ventura (Waterfall). Pleistocene: Lower San Pedro series of San Pedro and Deadman Island, rather common; Pleistocene near Barlow's Ranch and at the old irrigation ditch near Ventura (Arnold, 1903); "Saugus" near Ventura (Waterfall); lower part of the Pleistocene between Santa Paula and Ventura (coll. by Grant); Tomales Bay, Marin County (Dickerson) ; Pleistocene of Pacific Beach and Spanish Bight, San Diego (Arnold) ; lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan) ; upper San Pedro fauna of Los Cerritos, Long Beach, Crawfish George's, Deadman Island, and San Pedro (Arnold, 1903); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Kodiak Island and Cooks Inlet, Alaska, south to Scammons Lagoon, Lower California (Dall). This is a rather large, rather elongate, and strongly flexed shell, with the beaks rela- tively anterior. It is a very common species and has persisted from at least as early as the lower Miocene. Packard found it living at various depths in San Francisco Bay. According to Dall (1909) the species seems to occur in Japan under the name of dis- similis von Martens, 1865. TelUna tersa Gould, 1852, is supposed to be the young of M. nasuia. Macoma nasuta (Conrad) variety jacalitosana Arnold Macoma jacalilosana Arnold, U. S. Geol. Surv., Bull. 396, p. 65, pi. 16, fig. 2, January 15, 1910; Bull. 398, p. 110, pi. 38, fig. 2, 1910. Type specimen: In the U. S. National Museum, Cat. No. 156,613. Type locality: Just east of junction of Jacalitos and Jasper creeks, Coalinga region, California; Pliocene. Pliocene: Jacalitos formation, lower Pliocene of Coalinga district (Arnold). According to Arnold "M. jacalitosana belongs to the same general group as M. nasuta Conrad . . . but is very much more inflated, narrower posteriorly, and carries the posterior carina or fold much farther below the dorsal margin than the latter." Macoma nasuta (Conrad) variety kelseyi Dall Macoma kelseyi Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1052, pi. 49, fig. 7, December, 1900; U. S. Nat. Mus., Bull. 112, p. 47, 1921; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Station, Vol. 4, p. 53, March, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 171, 1924; Jordan and Hertlein, Proc. Calif. Acad. Sci,, Ser. 4, Vol. 15, p. 417, 1926. Macoma nasuta Conrad, var. kelseyi Dall, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 164, 1903. Shell like that of typical nasuia, but somewhat more elongate, often larger, with less flexure of the posterior end. Type specimen: In the U. S. National Museum. Type locality: San Diego, California; Pleistocene. Volume I ] PLIOCENE AND PLEISTOCENE MOLLXJSCA OF CALIFORNIA 367 Pliocene: Turtle Bay, Lower California, Mexico (Jordan and Hertlein) ; Etchegoin formation in well cores in the southern end of the San Joaquin basin (H. R. G.). Pleistocene: San Diego (Dall, 1900) ; foot of Twenty-sixth Street, San Diego (Arnold) ; rare in upper San Pedro series at San Pedro and Los Cerritos (Arnold). Recent: Puget Sound (L S. Oldroyd). This shell is similar to that of typical nasuta, but is narrower, less flexed and the pos- terior end is somewhat more obliquely truncated. The living range "San Diego and south" given by Arnold apparently on Ball's authority, must be an error. Mrs. Oldroyd has collected Recent specimens in Puget Sound, which is the only Recent record of this variety so far as the writers know. It is not certain whether this variety is of significance or not. Macoma inquinata (Deshayes) Plate 20, Figure 5 Tellina inquinata Deshayes, Proc. Zool. Soc. London for 1854, p. 357; Hanley, in Sowerby's Thes. Conch,, Vol. 1, Tellina, pi. 30, fig. 164, 1846; Reeve, Conch. Icon., Vol. 17, Tellina, pi. 30, species 164, 1867; Romer Syst. Conchyl. Cab., Vol. 10, p. 227, pi. 44, figs. 1-4, 1871±. Macoma inquinata Deshayes, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 689, 1864; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 93, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 248, 1888; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 307, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1053, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 162, pi. 16, fig. 4, 1903; U. S. Geol. Surv., Bull. 396, p. 164, pi. 29, fig. 3, 1910; Bull. 398, pi. 51, fig. 3, 1910; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 590, 596, 1913; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 252, 1916; Nomland, Vol. 10, p. 219, 1917; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 278, pi. 23, figs. 2, 3, pi. 24, figs, la-b, 1918; Dall, U. S. Nat. Mus., Bull. 112, p. 47, 1921; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922; Dall, Amer. Jour. Sci., Ser. 5, Vol. 4, p. 311, 1922; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Station, Vol. 4, p. 54, pi. 32, figs. 2a-b, 3a-b, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 172, pi. 45, figs. 2a-b, 3a-b, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924; T. S. Oldroyd, U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925. Shell of medium size, not always strongly flexed, moderately elongate, beaks anterior. Type locality: Vancouver Island, British Columbia; Recent. Pliocene: Etchegoin formation of the Coalinga region (Arnold and Anderson; Nomland); Merced and Purisima formations of middle California (Martin; Nomland); Twelve-Mile House, San Mateo County; San Fernando, Los Angeles County (Cooper). Pleistocene: Coos conglomerate of Coos Bay, Oregon (Arnold and Hannibal; Howe); "Pliocene" and lower San Pedro series of Deadman Island, Los Angeles County, common; foot of Twenty-sixth Street, San Diego (Arnold, 1903) ; lower San Pedro fauna of Nob Hill cut at San Pedro (T. S. Oldroyd) ; upper San Pedro series at Deadman Island, San Pedro, Los Cerritos, and Crawfish George's, Los Angeles County (Arnold, 1903) ; upper Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Bering Strait to Japan on the west and to Monterey Bay, Cahfornia, on the east (Dall, 1921). Macoma inquinata (Deshayes) variety amheimi Dall Macoma inquinata var. amheimi DaU, Proc. U. S. Nat. Mus., Vol. 52, p. 414, December 27, 1916; Amer. Jour. Sci., Ser. 5, Vol. 4, p. 311, 1922. Macoma inquinata amheimi Dall, U. S. Nat. Mus., Bull. 112, p. 47, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 172, pi. 42, fig. 9, 1924. Shell of medium size, short, not much flexed, beaks slightly anterior. Type specimen: In the U. S. National Museum, Cat. No. 122,537. Type locality: Kodiak Island, Alaska; Recent. ? Miocene: Quillayute formation near QuiUayute, Washington (Reagan'). Pleistocene: "Pleistocene of San Pedro" (Dall, 1921). Recent: Kodiak Island, Alaska, to San Francisco, California (Dall, 1921). > As Macoma inquinata Deshayes, Trans. Kansas Acad. Sci., Vol. 22, p. 209, 1909. Arnold and Hannibal CProc. Amer. Phil. Soc, Vol. 52, p. 604, 1913) concluded that Reagan's Quillayute fossils came originally from the Empire formation sandstones, but were transported by the aboriginees to the glacial filUng of the valley of the Quillayute River. 368 San Diego Society of Natural History [Memoirs Dall described this variety as follows: "Shell resembling the typical inquinata, but shorter, and relatively more plump; the beaks 15 mm. behind the anterior end; the basal margin somewhat produced; the rostration shorter, pronounced, and less obliquely twisted. Length, 38; height, 30; diameter, 15 mm." It is possible that this is the typical variety of inquinata. Dall (1922) considered Reagan's M. inquinata questionably equivalent to the variety arnheimi, which, if true, would extend the range of arnheimi to the Miocene. Macoma inquinata (Deshayes) variety afllnis Nomland Macoma inqxiinata affinis Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 233, pi. 9, figs. 1, la-b, April, 1917. Type specimen: In the University of California collection. Type locality: Coalinga district, San Joaquin Valley, California; Pliocene. Pliocene: Mya japonica zone, uppermost part of Etchegoin formation, upper Pliocene, Coalinga district, California (Nomland). According to Nomland, this variety "may be distinguished from the typical Macoma inquinata (Deshayes) by its larger size, the flange immediately anterior to the beaks, depressed area extending from umbones to posterior ventral margin, rather long liga- mental groove, and increased convexity near middle of base." This variety is somewhat like M. inquinata arnheimi Dall and like that variety is probably of no significance. Macoma brota Dall Tellina edenlula Broderip and Sowerby, Zool. Journ., Vol. 4, p. 363, January, 1829; Sowerby, Zool. Beechey's Voyage, H. M. S. Blossom, p. 154, pi. 41, fig. 5, pi. 44, fig. 7, 1839; Hanley, Descr. Cat. Rec. Biv. Shells, p. 71, 1842; Hanley, in Sowerby's Thes. Conch., Vol. 1, p. 315, pi. 65, fig. 243, 1847; ? Grewingk, Russisch-Kaiserliche Mineralogische Gesellschaft zu St.-Petersburg, Verhandlungen for the years 1848 and 1849, p. 357, pi. 7, figs. \a-c, 1850; not Tellina edenlula Spengler, 1793. Macoma edenlula Broderip and Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 307, 1900. Macoma brota Dall, Proc. U. S. Nat. Mus., Vol. 52, p. 413, December 27, 1916; Canadian Arctic Exped., Vol. 8, Pt. A, p. 29A, 1919; U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 170, pi. 9, fig. 2, 1924. Type specimen: Of M. brota Dall, in U. S. National Museum. Type locality: Bering Strait. f Tertiary: Tertiary of Alaksa, MoUer, Unga (Grewingk). Pleistocene: East and west sides of Coppermine River, Northwest Territories, Canada (Dall, 1919). Recent: Arctic Ocean, Bering Sea, south to Puget Sound (Dall, 1921). According to Grewingk, T. dilatata Girard' may belong to this species or to T. lutea. Dall considered Grewingk's specimens sufficiently different from Recent examples of "edentula" to rename the variety grewingki.^ The species is closely related to M. calcarea. Macoma brota Dall variety lipara Dall Macoma hrota, new variety, lipara Dall, Proc. U. S. Nat. Mus., Vol. 52, p. 414, December 27, 1916. Macoma brota lipara Dall, U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 171, pi. 42, fig. 6, 1924. Shell resembling that of brota, but more rotund, less rostrate, with a wider and rounder anterior end, shorter and more rounded posterior end, and more polished surface. * A. Erman'8 Archiv Wiss. Kunde RusslaDd, Vol. 3, p. 544, figs. 5a. 5b, 1S43. 2 Washington Acad. Sci., Alaaka. Res. Harriman Alaska Exped., Vol. 4, p. 116, 1904, reissued by the Smithsonian Institution, 1910. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 369 Type specimen: U. S. National Museum, Cat. No. 223,032. Recent: Bering Sea to Puget Sound (Dall, 1921). According to Dall, 1921, the variety and the typical form have the same geographical distribution; but variety lipara had not been seen from Arctic waters when originally described. The respective measurements are as follows, in millimeters: M. brota: height, 53 ; length, 74 ; diameter, 22 ; posterior end, 32 ; M. lipara : height, 57 ; length, 74 ; diameter, 25; posterior end, 33 (Dall, 1916). Howe appears to have considered this variety and Macoma astori Dall identical, but he did not use the older name. The variety lipara seems to be a little more evenly rounded posteriorly, and lacking sufficient authentic comparative material we have not disturbed Dall's arrangement. However, here as elsewhere, changes may be necessary when the group receives critical treatment. Macoma astori Dall Macoma astori Dall, U. S. Geol. Surv., Prof. Paper 59, p. 128, pi. 14, figs. 1, 11, April 2, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 590, 1913. Type specimen: In the U. S. National Museum. Type locality: Coos Bay, Oregon; Miocene. Miocene: Empire formation of Coos Bay, Oregon (Dall; Arnold and Hannibal). This species is very close to, if not identical with M. brota variety lipara Dall. From Howe's remarks,' it appears that Dall could not be relied upon in discriminating between these two forms, which goes to illustrate the futility of making such minute subdivisions. There seems to be a slight difference in the outline of the posterior profile of the shell, which is probably not more than would occur between two individuals of the same parents. The variety lipara is probably a superfluous name for M. astori, but is retained here until a thorough review of the Pacific coast Macomas permits these changes to be accompanied by a full discussion based upon large collections. Macoma calcarea (Gmelin) Tellina calcarea Gmelin, Systema Naturie, Ed. 13, Vol. 1, pt. 6, p. 3236, 1791; Hanley, Descr. Cat. Rec. Biv. Shells, p. 46, pi. 4, fig. 43, 1842; MoUer, Index Moll. Groen., p. 20, 1842; ? Hanley, Sowerby's Thes. Conch., Vol. 1, Tdlirui, p. 314, pi. 62, fig. 183, 1847. Tellina lata Gmelin, Systema Naturse, Ed. 13, Vol. 1, pt. 6, p. 3237, 1791. Tellina sabulosa Spengler, Skrift. Naturh. Selsk., Vol. 4, p. 114, 1794. Macoma tenera Leach, in Ross's Voy. of Discovery in H. M. S. Isabella and Alexander, Appendix 2, p. Ixii, 1819; Journ. de Phys., Vol. 88, p. 465, 1819. Tellina proxima (Brown MS.) Sowerby, Zool. Beeehey's Voy. Blossom, p. 154, pi. 44, fig. 4, 1839; Hanley, in Sowerby's Thes. Conch., Vol. 1, Tellina, p. 313, pi. 66, fig. 264, pi. 59, fig. 115, 1847; Forbes and Hanley, Hist. Brit. Moll., Vol. 1, p. 307, pi. 21, fig. 1, 1850; Vol. 4, p. 251, pi. 133, fig. 3, 1853. Tellina sordida Couthouy, Boston Journ. Nat. Hist., Vol. 2, p. 59, pi. 3, fig. 11, 1838. Sanguinolaria sordida Couthouy, Gould, Invert. Mass., p. 67, 1841. Macoma proxima Sowerby, Gould, Invert. Mass., Binney Ed., p. 95, fig. 401, 1870. Macoma calcarea Gmelin, Sars, Moll. Reg. Arct. Norv., p. 76, pi. 6, figs. 2a-h, 1878; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 124, 1868-9 (as of "Chemn. sp."); Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 248, 1888 (as of Chemnitz); Dall, Proc. U. S. Nat. Mus., Vol. 23, pp. 299, 307, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1046, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 161, pi. 16, fig. 2, 1903; Dall, Washington Acad. Sci., .\laska, Res. Harriman Alaska Exped., Vol. 4, p. 121, 1904; Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 126, 127, 1909; Weaver, Washington Geol. Survey, Bull. 15, p. 18, 1912; Arnold and Hannibal, Proc. Xmer. Philos. Soc, Vol. .52, pp. 590, 592, 1913; Weaver, Univ. Washington Publ. Geol., Vol. 1, no. 1, pp. 28, 32, 1916; ' Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922. 370 San Diego Society of Natural History [Memoirs Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 252, 1916; Dall, Canadian Arctic Exped., Vol. 8, Pt. A, p. 29A, 1919; Baker, Bull. Amer. Mus. Nat. Hist., Vol. 41, art. 11, p. 499, 1919; Dall, U. S. Nat. Mus., Bull, 112, p. 47, 1921; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 173, pi. 42, fig. .5, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 2.51, 253, 1929. Macoma sabulosa Spenglcr, Dall, E.xped. to Point Barrow, p. 183, 1885; Dall, in Spurr, U. S. Geol. Survey, 20th Ann. Kept., Pt. 7, p. 264, 1900; Dall, in Moffit, U. S. Geol. Surv., Bull. 533, p. 45, 1913; Dall, Canadian Arctic Exped., Vol. 8, Pt. A, p. 29A, 1919. "Tellina albaria (Conrad)," Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 184, pi. 2, fig. 15, 1909, not of Conrad. Oligocene: Upper Oligocene of western Washington (Weaver, 1912, 1916). Miocene: Empire formation of Coos Bay, Cape Blanco region, Oregon (Dall, 1909; Arnold and Hannibal); Bear River Miocene, questionably (Martin), probably Pliocene; Cape Yaktag, Alaska (Dall, in Spurr, 1900). Pliocene: Lower and middle parts of the Wildcat formation, northern California; Purisima formation south of San Francisco (Martin); Merced formation of middle California (Arnold and Hannibal); Pico formation near Ventura (Waterfall); near Nome, Alaska (Dall, in Moffit, 1913). Pleistocene: Coos conglomerate, Coos Bay, Oregon (Howe); "Pliocene" and lower San Pedro series of Dead- man Island, Los Angeles County (Arnold); "Saugus" formation near Ventura (Waterfall); foot of Twenty-sixth Street and at northeast side of Mission Bay, San Diego (Stephens); Pleistocene of Douglas Island, Juneau Harbor, Alaska (Dall, 1904); and of Arctic Sound, several localities, North- west Territories, Canada (Dall, 1919); Pleistocene of Scandinavia, Scotland, Greenland, etc. Recent: Arctic Ocean to northern Japan and to Monterey Bay, California; circumboreal (Dall, 1921). This is a widely distributed and ancient species. It is possible that the Oligocene forms belong to a different, but closely related species. There is a recognizable, individual variation in shape, but Hanley's figure of calcarea in the "Thesaurus Conchyliorum" appears to be extreme. The few synonyms given above seem to be almost beyond question. Macoma moesta (Deshayes) Plate 20, Figure 3 Tellina moesta Deshayes, Proc. Zool. Soc. London for 1854, p. 361. Tellina lutea Krause, 1885, not Gray, 1828', fide Dall, 1900. Macoma krausei Dall, Proc. U. S. National Museum, Vol. 23, pp. 298, 307, 322, pi. 4, fig. 8, November 14, 1900. Macoma moesta Deshayes, Dall, U. S. Nat. Mus., Bull. 112, p. 47, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 173, 1924. ? Pliocene: Etchegoin formation of the Federal Exploration Company well, Kinsella No. 1, near Tipton, Tulare Co., San Joaquin basin, depth 2393 to 3175 feet, middle or upper Pliocene, about ten specimens, most of them poor (H. R. G.). Recent: Arctic Ocean, Bering Sea, Shumagin Islands; circumboreal (Dall, 1921). According to Dall (1900), M. krausei is "characterized by its oval compressed form, low posterior beaks, and short, hardly flexed posterior end." M. krausei is a synonym of M. moesta. The Etchegoin specimens, upon which the Pliocene record is based, vary in shape, but some of them match the typical form. They are like M. calcarea except that the pos- terior instead of striking off abruptly is rounded out, somewhat like the posterior end of M. secta without the cut. This rounding out of the posterior end as well as the anterior gives the shell an unusually large apical angle, with beaks hardly protruding. The hinge is weak. One of the Etchegoin specimens is larger than Dall's and relatively deeper. This is the only species we have noted with posterior beaks, rounded ends, large apical angle, and weak hinge, which are characters exhibited by nearly all of the Etchegoin specimens. One or two specimens have an apical angle more like that of M. calcarea, but most of them have a convex posterior dorsal edge which refuses to fit the outline of calcarea. Perhaps this form should be considered a variety of M. calcarea, with which it intergrades. 1 The original descriptions of Krause, 1SS5, and of Gray, 1828. have not been seen by the present authors. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 371 Macoma moesta (Deshayes) variety acolasta Dall Plate 14, Figure 7; Plate 20, Figures 4a, 46, 10 Macoma acolasta Dall, West American Scientist, Vol. 19, No. 3, p. 21, June 15, 1921; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 19, pi. 8, figs. 2, 3, 1925; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Shell small, inequilateral, inequivalve, posterior end somewhat bent to the right, surface smooth, except for faint incremental Imes which are stronger on the posterior area; beaks not prominent, nearer the posterior end; both dorsal slopes somewhat arched, anterior end evenly rounded, base slightly arcuate, posterior end very slightly rostrate ; left valve more convex; hmge feeble, right valve with two small cardiitals, left valve with a single bifid tooth; pallial sinus in the left valve, sul)ovate, reaching a little beyond the middle of the valve, the lower two-thirds coalescent with the pallial Ime; in the right valve the sinus almost triangular. Height, 12; length, 22; diameter, 6.5 mm. (Dall, 1921.) Type specimen: In the U. S. National Museum. Type locality: San Quintin Bay, Lower California, Mexico; Pleistocene. Pleistocene: San Quintin Bay, west coast of Lower California, Mexico (Dall); locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. (U. S. G.). This variety is like typical moesta, but is more elongate. The beaks are nearer the angulated end, as in M. calcarea, to which it is possibly related, but the dorsal area under the beaks is not concave and the shell is more elongate than that of calcarea. Jordan attributed an upper Pleistocene age to the San Quintin Bay deposits from which the type of this variety was collected. Macoma balthica (Linnaeus) Plate 14, Figures 6a, 66; Plate 20, Figures 7a, 76 Tellina halthica Linna;us, Syst. Nat., Ed. 10, p. 674, 1758; Ed. 12, p. 1116, 1767; Born, Test. Musei Ca:sarei Vindo- bonensis, p. 38, pi. 2, fig. 14, 1780; Chemnitz, Neues Syst. Conch. Cab., Vol. 6, p. 133, pi. 13, fig. 128, 1782; Hanley, in Sowerby's Thes. Conch., Vol. 1, Tellina, p. 316, pi. 59, fig. 121, 1847. Venus fragilis O. Fabricius, Fauna Groenl., p. 413, 1780, not of Linnseus, fide Hanley, 1847, and Dall, 1900. Psammobia fusca Say, Journ. Acad. Nat. Sci. Phila., Vol. 5, p. 219, 1827. Tellina inconspicua Broderip and Sowerby, Zool. Journ., Vol. 4, p. 363, 1829; Sowerby, Zool. Beechey's Voy., p. 153, pi. 41, fig. 6, 1839; Mighels, Boston Journ. Nat. Hist., Vol. 4, p. 317, 1843; Hanley, in Sowerby's Thes. Conch., Vol. 1, Tellina, p. 317, pi. 59, fig. 120, 1847. Sanguinolaria fusca Say, Conrad, .\iner. Marme Conch., p. 34, pi. 7, fig. 1, 1831; Gould, Inv. Mass., p. 66, fig. 42, 1841. Tellina gronlandica (Beck MS.) Lyell, Trans. Geol. Soc. London, Ser. 2, Vol. 6, p. 137, pi. 16, figs. 8, 8a, 1839. Tellina fusca Say, Philippi, Abbild. und Beschr., Vol. 2, Tellina, p. 24, pi. 3, fig. 3, 1845; Hanley, in Sowerby's Thes. Conch., Vol. 1, Tellina, p. 316, pi. 59, fig. 117, 1847. Tellina fabricii Hanley, in Sowerby's Thes. Conch., Vol. 1, Tellina, p. 318, pi. 49, fig. 112, 1847. Macoma fusca Say, Gould, Inv. Mass., Binney Ed., p. 93, fig. 42, 1870. Macoma inconspicua Broderip and Sowerby, Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896; Canadian Arctic Exped., Vol. 8, Pt. A, p. 29A. 1919. Macoma halthica Linnaeus, Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 1051, 1053, 1900; Proc. U. S. Nat. Mus., Vol. 23, p. 298, 1900; Canadian Arctic Exped., Vol. 8, Pt. A, p. 29A, 1919; U. S. Nat. Mus., Bull. 112, p. 47, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 172, pi. 44, figs. 1, 2, 9, 1924. Macoma balthica Linne, var. inconspicua Broderip and Sowerby, DaU, Washington Acad. Sci., .Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 121, 1904, reissued by Smithsonian Institution, 1910. Suborbicular, shghtly triangular, thick, equilateral, more or less ventricose, white or pale flesh colored, with the interior usually rosj', smooth, not glossy; ventral edge arcuated, rising behind; front dorsal edge short and not much sloping, nearly straight adjacent to the prominent beaks, be- coming convex subsequently; hinder dorsal edge nearly straight or but shghtly convex, much slop- ing; anterior side rounded; posterior side angulated, but with the tip rountled; ligament large, and prominent; fold and flexure obsolete; teeth small. (Hanley.) Length, 16 to 27 mm.; height, 14 to 22 mm. 372 San Diego Society of Natural History [Memoirs Miocene: St. Paul Island, Alaska, and Miocene of British Columbia (Dall, 1896, as M. inconspicua). Pliocene: California (Dall, 1896, as inconspicua). Pleistocene: Douglas Island, Juneau Harbor, Alaska (Dall, 1904, as M. balthica var. inconspicua); south- west part of Victoria Island, Northwest Territories (Dall, 1919, as inconspicua); Coppermine River, five miles from its mouth. Northwest Territories (Dall, 1919); various other northern and north- eastern localities (Lyell; etc.); California (Dall, 1896, as inconspicua). Recent: Point Barrow, Arctic Ocean, to northern Japan and San Diego, California (Dall, 1921); also north Atlantic, Baltic. Dall reported this species from the Pliocene and Pleistocene of California, but did not give precise localities. Macoma pabloensis Clark,' of the upper Miocene of middle California, seems to be related, but is more rounded. Macoma planiuscula, new species Plate 14, Figures llo, lib; Plate 20, Figures 8a, 8b "Macoma carlollensis Whiteaves," Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 308, 1900; Bull. 112, U. S. Nat. Mus., p. 47, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 175, 1924; and of other recent Pacific coast authors; not of Whiteaves, 1880. ? "Tellina carlollensis Whitesives," Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896. Shell resembling that of Macoma balthica (Linneeus), but somewhat more elongate, with the valves significantly flatter, the right valve sHghtly flexed to the right at the posterior end; shell moderately heavA', surface polished. Dimensions: Length, 23.5 mm.; height, 16 mm.; convexity of the two valves, 6 mm. Type specimen: In the Oldroyd Collection at Stanford University, labeled 301-lA. Type locality: Nunivak Island, Alaska; Recent. f Miocene: Nulato, St. Paul Island, Nushagak, Unalaska, Alaska; also British Columbia (Dall, 1896, as "Tellina carloltensis Whiteaves." Recent: Arctic Ocean to Puget Sound (Dall, 1921, as "carloltensis'"). Authentic specimens of Macoma carloltensis Whiteaves (Rept. Geol. Surv. Canada for 1878-79, p. 196B, fig. 1, 1880) from the Museum of the Canadian Bureau of Mines at Ottawa, when compared with Dall's discussions and with specimens identified by Dall as of Whiteaves' species, show that Dall confused carloltensis with a Recent form appar- ently undescribed. This unfortunate confusion resulted in Dall's redescribing the type carloltensis under the name of Macoma inflatula.- Macoma quadrana Dall appears to be very close to inflatula ( = carloltensis Whiteaves). The true carloltensis is figured on plate 20, figures la, lb, 2a, 2b. Tellina ? diabloensis Clark (Univ. Calif. Publ. Geol., Vol. 8, p. 471, pi. 61, fig. 5, 1915, not Macoma diabloensis Clark, p. 475, pi. 61, figs. 8, 9, 10, 1915) has the shape of M. planiuscula, but the similarity is superficial, as Clark's species has the lateral teeth of a Tellina. Macoma middendorffi Dall Tellina edentula Middendorff, Siber. Reise, p. 259 in part, pi. 21, fig. 1 only, 1850, fide Dall, 1884. Macoma (edentula Brod. and Sby. var ?) middendorffi Dall, Proc. U. S. Nat. Mus., Vol. 7, p. 247, 1884. Macoma edentula Brod. and Sby. \ax . middendorffii Dall, Proc. U. S. Nat. Mus., Vol. 9, p. 308, pi. 4, fig. 11, 1886. Macoma middendorfii Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896. Macoma middendorffii Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 306, 1900; in Moffit, U. S. Geol. Surv., Bull. 533, p. 46, 1913; Dall, Prof. Paper 125-C, p. 33, pi. 6, figs. 11, 13, 1920; U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 170, pi. 53, fig. 1, 1924. ' Univ. Calif. Publ. Geol., Vol. 8, pp. 475, 476, pi. 61, Bgs. 1, 2, 17, 1915. ~- Bull. Nat. Hist. Soc. Brit. Columbia, No. 2, p. 11, pi. 1, figs. 19, 20, 1897; figured also by Oldroyd. Stanford Univ. Publ. Geol.. Vol. 1, pi. 13, fig. 15, pi. 1, figs. 2, 8. 1924. VoLDME I ] Pliocene and Pleistocene Mollusca of California 373 Type specimen : In the U. S. National Museum. Type locality: Bering Sea; Recent. Miocene: St. Paul Island, Nushagak, Port MoUer, Morzhowi, Unga Island, Alaska (Dall, 1896). Pliocene: Just west of Snake River and at a number of Pliocene localities in the Nome region of Alaska (Dall, 1913, 1920). Recent: Bering Strait, south to the Commander and Aleutian Islands and eastward to Chirikoff Island, Alaska (Dall, 1921). According to Dall, this species is recognizable "by its high triangular form, solid shell, with broad hinge plate and flattened left valve." He suggested (1886) that it might be a race of edentula, due to peculiar environmental conditions. Macoma incongrua (von Martens) Tellina incongrva von Martens, Ann. Mag. Nat. Hist., Ser. .3, Vol. 16, pp. 430, 431, 1865. Tellina rotundata Sowerby, in Reeve's Conch. Icon., Vol. 17, Tellina, pi. 27, fig. 146, June, 1867. Macmna incongrua von Martens, DaU, Proc. U. S. Nat. Mus., Vol. 23, p. 306, 1900; U. S. Nat. Mus., Bull. 112, p. 46, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 170, pi. 42, fig. 10, 1924. Macoma rotundata Sowerby, Dall, in Moffit, U. S. Geol. Surv., Bull. 533, p. 46, 1913. Type locality: Of incongrua, Yokohama, Japan; Recent. Pliocene: Center Creek, and of the second beach, east of Nome, Alaska (Dall, 1913). Recent: Arctic Ocean, south to Japan on the west and to San Diego, California, on the east (Dall, 1921). According to Dall (1900), TeUina nasuta var. truncata of Middendorff, 1851 (not Tellina truncata Jonas, 1844) and Macoma calif orniensis Bertin, 1878, are synonyms. Macoma yoldiformis Carpenter Macoma yoldiformis Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864; Proc. Acad. Nat. Sci. Phila. for 1865, p. 56, 1865; Cooper, 7th .-Vnn. Rept. Calif. State Mineralogist, p. 249, 1888; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 309, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 165, pi. 16, fig. 6, 1903; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 252, 1916; Dall, U. S. Nat. Mus., Bull. 112, p. 48, 1921; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 177, pi. 44, fig. 6, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pliocene: Middle Wildcat formation of northern California (Martin). Pleistocene: Lower San Pedro series of Deadman Island, rare (Arnold); "Saugus" formation, near Ventura (Waterfall); Spanish Bight, San Diego Bay, common (Arnold); upper Pleistocene at San Ignaeio Lagoon and San Quintin Bay, west coast of Lower California, Mexico (Jordan, 1924, 1926). Recent: Puget Sound to San Diego, California. This is a small, thin, smooth shell something like TeUina bodegensis, but smaller, more evenly rounded posteriorly, and with weaker concentric sculpture. Its name is appropriate and suggests its shape. Section Rexithaerus Conrad, 1869 Rexithserus Conrad, in Tryon, "Catalogue of Tellinidse," p. 104, Supplement to Amer. Journ. Conch., Vol. 4, pt. 5, 1869; Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 292, 1900; Trans. Wagner Inst. Sci., Vol. 3, p. 1045, 1900. Type (by subsequent designation, Dall, 1900), Macoma secta Conrad. Shell large, inequivalve, with a smooth surface, a large and strong, deep-set ligament, behind which the dorsal margin is conspicuously produced upward (Dall). 374 San Diego Society of Natural History [Memoirs Macoma secta (Conrad) Plate 20, Kgures 60, 6b Tellina secta Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 257, 1837; Hanley in Sowerby's Thes. Conch., Tellina, p. 327, pi. 65, figs. 245, 248, 1847. Macoma secta Conrad, H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 401, 1858: Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 249, 1888; Keep, West Coast Shells, p. 191, fig. 163, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 164, pi. 16, fig. 5, 1903; Arnold, U. S. Geol. Surv., Bull. 396, p. 30, pi. 20, fig. 1, Jan. 15, 1910; Arnold and Anderson, Bull. 398, pp. 110, 131, 318, pi. 42, fig. 1, 1910; Thompson, Rept. B. C. Commissioner of Fisheries for 1912, pp. 1-41, 1-48, pi. 8, 1913; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Clark, Vol. 8, pp. 404, 418, 1915; Martin, Vol. 9, p. 252, 1916; Weaver, Univ. Wash. Publ. Geol., Vol. 1, pp. 28, 33, 1916; Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 211, 219, 330, 1917; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 280, pi. 25, fig. 8, 1918; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 44, pi. 12, figs. 3, 4, pi. 13, fig. 1, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 48, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 178, pi. 44, fig. 8, 1924; Jordan, Bull. So. CaUf. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. "Macoma var. edulis, Nutt.", Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864. Macoma {Rexilhsmis) secta Conrad, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1053, 1900. Type specimen: ? In the Academy of Natural Sciences of Philadelphia. Type locality: San Diego, California; Recent. Miocene: Lower Neocene; Scutella breweriana zone; Santa Margarita formation; lower and upper parts of San Pablo formation of middle California (Clark ; Nomland) ; Montesano formation, upper Miocene, Washington (Weaver); Empire formation of western Oregon. Pliocene: San Fernando (Cooper) ; lower Fernando of Holser Canyon, Los Angeles County (English) ; Etche- goin formation of the Coalinga region (Arnold, 1910; Martin; Nomland); upper part of the Wildcat formation of northern California (Martin) ; Etchegoin of the Sargent oil field, near Sargent (Martin ) ; Santa Barbara (Cooper, as Pliocene). Pleistocene: Santa Barbara to San Diego (Cooper) ; lower San Pedro series of Deadman Island and San Pedro (Arnold, 1903); Coos conglomerate of Coos Bay region, Oregon (Howe); Spanish Bight, San Diego Bay (Arnold, 1903) ; lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan, 1924) ; upper San Pedro series at Deadman Island, Los Cerritos, Crawfish George's, San Pedro, and Long Beach (Arnold, 1903); upper San Pedro fauna at Santa Monica (T. S. Oldroyd collection); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Vancouver Island, British Columbia, south to Gulf of California, Mexico; also Japan. This common shell has a trapezoidal shape and a smooth, polished surface when fresh. Dall (1900) states that Tellina ligamentiyia Deshayes, 1843, Tellina japonica Deshayes, 1854, and Tellina denticuldta of Sowerby, 1867, not of Deshayes, 1854, are synonyms. Macoma indentata Carpenter Macoma indentata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 639, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 248, 1888; Keep, West Coast Shells, p. 195, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 185, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 161, 162, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 526, 1907; EngUsh, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Martin, Vol. 9, p. 252, 1916; Nomland, Vol. 10, p. 300 (questionably), 1917; Dall, U. S. Nat. Mus., Bull. 112, p. 48, 1921; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 178, pi. 44, fig. 4, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Macoma (Rexithserus) indentata Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 309, 1900. ? Macoma {Rexithserus) indentata var. tenuirostris Dall, Proc. U. S. Nat. Mus., Vol. 23, p. 309, 1900. ? Macoma indentata tenuirostris Dall, U. S. Nat. Mus., Bull. 112, p. 48, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 178, 1900. Type locality: San Pedro, California; Recent. Miocene: El Toro Ranch, Monterey County; Griswold's, San Benito County (Cooper); Empire formation of Coos Bay, Oregon (Howe); Santa Margarita formation, upper Miocene, north of Coalinga (Nom- land). Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 375 Pliocene: Etchegoin formation of the Coalinga region (Martin; Nomlaud, questionably) ; lower Fernando of Elsmere Canyon (Arnold, 1907; English, 1914) and of Holser Canyon, Los Angeles County (Eng- lish); Etchegoin of Sargent oil field (Martin). Pleistocene: Coos conglomerate of Coos Bay, Pliocene or Pleistocene (Howe); lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd, 1925); Spanish Bight, San Diego (Arnold, 1903); upper San Pedro at Los Cerritos and San Pedro, rare (Arnold, 1903) ; upper San Pedro at Santa Monica (F. C. Clark collection); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Puget Sound to Lower California, Mexico. Macoma molinana Dall Macoma rnoUnana Dall, U. S. Geol. Surv., Prof. Paper 59, p. 128, pi. 14, fig. 12, April 2, 1909; Weaver, Washington Geol. Surv., Bull. 15, p. IS, 1912. Type specimen: In the U. S. National Museum, Cat. No. 154,088. Type locality: Miller's Beach, Coos Bay, Oregon; Oligocene or lower Miocene. Oligocene or Miocene: Miller's Beach, Coos Bay, Oregon (Dall); Blakeley formation, western Washington (Weaver, as lower Miocene). This form looks very much like M. indentata Carpenter, judging from Ball's type figure, but it is larger. It is almost surely a synonym. Macoma vanvlecki Arnold Macoma vanvlecki Arnold, U. S. Geol. Surv., Bull. 396, p. 65, pi. 12, fig. 2, pi. 16, fig. 1, January 15, 1910; Bull. 398, pp. 110, 302, 310, pi. 34, fig. 2, pi. 38, fig. 1, 1910. Type specimen: In the U. S. National Museum, Cat. No. 165,576. Type locality: Fourteen miles southwest of Coalinga; Jacalitos formation, lower Pliocene. Pliocene: Jacalitos formation of the Coalinga region (Arnold). This form is probably a variety of M. indentata. From the JacaUtos formation, lower Pliocene of the Coalinga region, Arnold reported and figured' a species presumably of Macoma which was so poorly represented that no specific name was assigned to it. Arnold's figure recalls Taras parilis (Conrad). "Macoma kerica" Hendrickson may be a synonym of Cryptomya californica, but the type material is poor. Family SEMELIDAE Genus SEMELE Schumacher, 1817 Semele Schumacher, Essai d'un Xouv. Syst. Habit. Vers Test., p. 165, 1817, only species Tellina reticulata Spengler; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 985, 1900; Woodring, Carnegie Inst., Publ. No. 366, p. 178, 1925. Amphidesma Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 489, 1818; Bowdich, Elem. Conch., Pt. 2, p. 8, pi. 2, fig. 18, 1822. Type (by monotypy), Tellina reticulata Spengler = Tellina proficua Vulteney; Carib- bean; Recent. This genus is most abundantly represented in the tropical and warm temperate seas. It dates back at least to the middle Eocene. 1 U. S. Geol. Sxirv., Bull. 396, p. 64. pi. 15, fig. 3, 1910. 376 San Diego Society of Natural History [Memoirs Semele decisa (Conrad) Plate 14, Figures 13a, 136 Amphidesma decisa Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 234, pi. 19, fig. 2, 1837. Semele decisa Conrad, Carpenter, Proc. Zool. Soe. London for 1856, p. 213, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, p. 640, 1864; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 94, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 264, 1888; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 995, 1900; Baker, Nautilus, Vol. 16, p. 42, 1902; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 165, 1903; Dall, Proc. Acad. Nat. Sci. Phila., for 1915, p. 25; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 45, pi. 13, fig. 2, 1920; DaU, U. S. Nat. Mus.; Bull. 112, p. 48, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 179, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type locality: San Diego, California; Recent. Pleistocene: Lower San Pedro series at San Pedro, rare; foot of Twenty-sixth Street, San Diego; common in the upper San Pedro series at Los Cerritos, but rarer in the same horizon at Deadman Island and San Pedro (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to San Martin Island, Lower California, Mexico (Baker); Point Abreojos, Lower California (Hemphill Collection at Stanford University). Semele flavescens (Gould) Amphidesma flavescens Gould, Proc. Boston Soc. Nat. Hist., Vol. 4, p. 89, November, 1851. Amphidesma proximum C. B. Adams, Ann. New York Lyceum Nat. Hist., Vol. 5, p. 513, 1852 (pagination of separate, p. 289). Semsle flavescens Gould, Dall, Proc. Acad. Nat. Sci. Phila. for 1915, p. 25; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 154, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Type locality: San Diego, California; Recent. Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: San Pedro, California (in Oldroyd Collection at Stanford tfniversity), to Callao, Peru (Jordan); Scammons Lagoon, Lower California, Mexico (Hemphill Collection at Stanford University). Semele rubropicta Dall Semele rubropicta Dall, Amer. Journ. Conch., Vol. 7, p. 144, pi. 14, fig. 10, 1871; Arnold, U. S. Geol. Surv., Bull. 396, p. 156, pi. 25, fig. 3, Jan. 15, 1910; Bull. 398, pi. 47, same figure, 1910; Dall, Proc. Acad. Nat. Sci. Phila. for 1915, p. 26; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 254, 1916; Nomland, Vol. 10, p. 220, 1917; Dall, U. S. Nat. Mus., Bull. 112, p. 48, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. ISO, pi. 43, fig. 10, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In the U. S. National Museum. Type locality: Soquel, Monterey Bay, California; Recent. Pliocene: Upper part of Etchegoin formation in Coalinga region, Fresno and ICings counties, California (Ar- nold, 1910; Nomland, 1917); Merced Pliocene of Sargent oil field, San Benito County (Martin). Pleistocene: Lower San Pedro fauna of Nob Hill cut , San Pedro (T. S. Oldroyd) ; lower Quaternary at Magda- lena Bay and upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926). Recent: Forrester Island, ,\laska, to Tia Juana, Lower California, Mexico (Dall, 1921). Semele fausta Nomland Semele fausta Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 233, 234, pi. 9, figs. 3, 3a, 3fc, 1917. Type specimen: In the University of California collection, No. 11,102. Type locality: On Zapato Creek, Fresno County; Etchegoin, Pliocene. Pliocene: Rare and known onh' from the Pecten coalingensis zone of Coalinga district (Nomland). "This form is of the same general type as Semele rubropicta Dall, from which it may be distinguished by its having a greater length in jiroportion to the width, the anterior portion being longer, the fold more nearly obsolete, and by the long, straight, anterior dorsal margin. The hinge also differs in having the weak, narrow resilifer and long, narrow laterals, this being especially true of the anterior teeth." (Nomland.) Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 377 Semele incongrua Carpenter Semele incoHgrua Carpenter, Brit. Assn. Adv. Sci., Kept, for 1S63, p. 640, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 208, 1864; Dall, Proc. Acad. Nat. Sci. Phila. for 1915, p. 27; U. S. Nat. Mus., Bull. 112, p. 49, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 181, pi. 11, figs. 12, 13, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925. Type specimen: In the University of California collection, No. 1,061. Type locality: Santa Barbara, California; Recent. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd). Recent: Monterey, California, to the Coronados Islands, Lower California, Mexico (Dall, 1921). Semele incongrua Carpenter variety monterejd Arnold Semele pulchra Sowerby, var. montereyi Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 166, pi. 15, figs. 3, 3a (not 4, 4a), 1903; Dall, Proc. Acad. Nat. Sci. Phila. for 1915, p. 27. Type specimen: In the U. S. National Museum. Type locality: Deadman Island, San Pedro Harbor; Pleistocene. Pleistocene: Rare in lower San Pedro series at Deadman Island,' Los Angeles County (Arnold). This appears to be a rare, extinct variety. Arnold originally reported it (on the authority of Dall) as living at Monterey, but the Recent form is the typical variety of incongrua. Semele pulchra (Sowerby) Amphidesma pvlchrum Sowerby, Proc. Zool. Soc. London for 1832, p. 57; Conch. lUustr., Amphidesma, fig. 5, 1833. Semele pulchra Sowerby, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 640, 1864; Gabb, Geol. Surv. Calif., Palso., Vol. 2, p. 94, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 264, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 166, pi. 15, figs. 1, la, 1903; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 272, 1909; Proc. Acad. Nat. Sci. Phila. for 1915, p. 27; U. S. Nat. Mus., Bull. 112, p. 49, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 181, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: ? In the British Museum. Type locality: Bay of Caracas, South America. Pleistocene: Foot of Twenty-sixth Street, San Diego (Arnold); rather rare in the ujiper San Pedro series at San Pedro and Los Cerritos (Arnold); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Ecuador (Dall, 1921). Semele quentinensis Dall Semele quentinensis Dall, West American Scientist, Vol. 19, No. 3, p. 22, June 15, 1921 ; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 26, pi. 8, fig. 4, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimen: In the U. S. National Museum. Type locality: San Quintin Bay, west coast of Lower Cahfornia, Mexico; Pleisto- cene (upper Pleistocene, according to Jordan). Pleistocene: At the type locality. Genus CUMINGIA Sowerby, 1833 Cumingia Sowerby, Proc. Zool. Soc. London, Pt. 1, p. 34, May, 1833; Gray, Pt. 15, p. 187, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 998, 999, 1900. Type (by subsequent designation. Gray, 1847), Cumingia lamellosa Sowerby, Pacific coasts of North, Central, and South America. * About two years ago, Deadman Island was removed in the course of harbor improvement. Representative collections of fossil mollusks from this classic locality are to be found at Stanford University, at the California Academy of .Sciences, at the Los Angeles Museum, at the California Institute of Technology, and at the San Diego Society of Natural History. 378 San Diego Society of Natural History [ Memoirs Cumingia lamellosa Sowerby Plate 14, Figure 23; Plate 19, Figure 1 Cumingia lamellosa Sowerby, Proc. Zool. Soc. London, Pt. 1, p. 34, May, 1833; Conch. Icon., Vol. 19, Cumingia, pi. 1' fig. 5, 1873; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1001, 1900; Proc. U. S. Nat. Mus., Vol. 37, p. 272, 1909; E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2 (p. 42), 1919; Dall, U. S. Nat. Mus., Bull. 112, p. 49, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 182, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 253, 255, 1929. Cumingia Irigonularis Sowerby, op. cit., p. 34, 1833. Cumingia californica Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 234, pi. 17, fig. 12, 1837; Gabb, Geol. Surv. Calif., Palffio., Vol. 2, p. 94, 1868-9; Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 238, 1888; Keep, West Coast Shells, p. 196, fig. 168, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 186, 1892; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 1001, 1900; Arnold, Mem. Calif. Acad. Sci., Vol, 3, p. 167, 1903. Type specimens: Of lamellosa, in the British Museum; of californica, in the Academy of Natural Sciences, Philadelphia ?. Type localities: Of lamellosa, Chile; of californica, near Santa Barbara. Pleistocene: Santa Barbara (Cooper, possibly upper Pliocene); "Pliocene" of Deadman Island (collection at Stanford University) ; lower San Pedro series of Deadman Island, Crawfish George's, and San Pedro (Arnold) ; lower San Pedro fauna of Nob Hill cut at San Pedro (T. S. Oldroyd) ; San Diego (Cooper) ; at the entrance to the abandoned coal mine and other nearby localities on Point Loma and at Torrey Pines, San Diego County (F. Stephens) ; at the "Chiton bed" on Point Firmin, Los Angeles County (E. P. and E. M. Chace); Todos Santos Bay, Lower California, Mexico (Dall, 1900). Recent: Crescent City, California, south to Payta, Peru (Dall), and to Chile (Sowerby). Cumingia densilineata Dall Cumingia densilineata Dall, West American Scientist, Vol. 19, No. 3, p. 22, 1921; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 15, pi. 8, fig. 5, pi. 11, fig. 2, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, pp. 245, 248, pi. 25, figs. 1, 3, 5, 1926. Type specimen: In the U. S. National Museum. Type locality: San Quintin Bay, west coast of Lower California, Mexico; Pleistocene. Pleistocene: Upper Pleistocene at the type locality (Jordan). Family DONACIDAE Genus DONAX Linnaeus, 1758 Donax Linnaeus, Syst. Nat., Ed. 10, p. 682, 1758; Schumacher, Ess. Nouv. Syst. Habit. Vers Test., pp. 48, 144, 1817; Children, Quart. Jour. Sci., Lit., and Arts, p. 308, January, 1823; Herrmannsen, Indicis Gen. Malac, Vol. 1, pp. 402-404, 1847; Gray, Proc. Zool. Soc. London, Pt. 15, p. 187, 1847; H. and A. Adams, Gen. Rec. Moll., Vol. 2, pp. 403, 404, 1856; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 133, 1871 ; Bertin, Nouv. Arch. Mus. Hist. Nat. Paris, Ser. 2, Vol. 4, pp. 77-79, 1881 ; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 964-966, 1900; Woodring, Carnegie Inst., Publ. No. 366, pp. 180, 181, 1925. Chion Scopoli, Introductio ad Historiam Naturalem, p. 398, 1777, only species, "Dana.r denliculata Linn." Type (by subsequent designation, Herrmannsen, Apr. 18, 1847, and Gray, Nov., 1847), Donax rugosus Linnaeus; West Indies; Recent. The genus Donax comprises small, equivalved, often wedge-shaped shells (shells with the outline of a right or obtuse-angled triangle), which generally occur on sandy beaches in tropical and temperate regions. The shells are small, strong, without epidermis, and are sometimes much shorter posteriorly than anteriorly. Some species are trigonal in shape, with high umbones, while a few are elongate and somewhat Modioliform. The genus has a complex synonymy, which is partly elucidated by Dall in the reference given above. Herrmannsen designated Donax rugosus as the type of the genus Donax restricted Volume I ] PlIOCENE AND PLEISTOCENE MoLLXJSCA OF CALIFORNIA 379 by Schumacher. It matters not whether the apphcation of this designation to the Lin- nsean conception of the genus be accepted or not, for one year later Gray designated the same type, applying it specifically to Donax Linnaeus. Children's type designation is in- valid because the species designated, Donax scortum (Linnseus), was not in the original list of species of Donax, being described as a Venus. In Lamarck's "Prodrome," Donax trunculus is given as an example, and although this does not constitute type designation, many writers have considered it as such. Section Serrula Chemnitz in Morch, 1853 Semila Chemnitz, Morch, Cat. Yoldi, Pt. 2, p. 18, 1853, including D. trunculus Linnseus; H. and A. Adams, Gen. Rec. MoU., Vol. 2, p. 405, 1856; Bertin, Nouv. Arch. Mus. Hist. Nat. Paris, Ser. 2, Vol. 4, p. 86, 1881; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 965, 1900, type, "D. trunculus (L.) Hanley," in syn. of Donax, s. I. Type (by subsequent designation, Dal, 1900), D. trunculus Linnseus; figured in Reeve's Conch. Icon., Vol. 8, Donax, pi. 4, figs. 23a-b, 1854; European seas. Shell ovate-triangular, wedge-shaped, gibbous anteriorly; margin of valves strongly denticu- lated. Hinge with the cartilage-fissure oblong. (H. and A. Adams.) Serrula was used by Chemnitz,' but not in a definitely generic sense. The name can date from Morch, who used it in classifying the Yoldi collection. Dall designated the type in IQOO.^ The California species of Donax have been in a state of confusion for years, but in a recent paper, Strong^ has done much to clarify the situation. Donax califomicus Conrad Donax califomica Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 254, pi. 19, fig. 21, 1837; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 968, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 170, pi, 13, fig. 9, 1903; Keep, West American Shells, p. 88, 1911; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 47, pi. 16, fig. 1, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 49, 1921; Strong, Nautilus, Vol. 37, p. 83, 1924; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 1, p. 183, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; not D. califomicus Conrad, of Car- penter, 1864, Cooper, 1888, Keep, 1888, 1892, nor of Williamson, 1892, which = D. gouldii Dall, 1921. Donax navicula Sowerby, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 640, 1864, not of Sowerby, 1854. Donax califomicus Conrad, Bertin, Nouv. Arch. Mus. Hist. Nat. Paris, Vol. 6, p. 92, 1881. "Donax flexuosus Gould," Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 238, 1888; Keep, West Coast Shells, p. 192, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 186, 1892; not of Gould, Boston Journ. Nat. Hist., Vol. 6, p. 394, pi. 15, fig. 8, 1857, which = D. striatus Linna;us, 1759, West Indies. Shell elongated, somewhat pointed at both extremities; discs with very minute radiating lines; color yellowish, obscurely rayed ; a brown stripe on the anterior and posterior submargin ; within white and purplish bro\v7i ; margin beautifully crenulated. (Conrad, 1837.) Type locality: Near Santa Barbara; Recent. Pleistocene: Santa Barbara to San Diego (Cooper); lower San Pedro series at Deadman Island and San Pedro, rare (Arnold) ; lower San Pedro of Nob Hill cut at San Pedro (T. S. Oldroyd) ; upper San Pedro series at San Pedro (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to Panama fl. S. Oldroyd). > Neues Syst. Conchyl. Cab., Vol. 6, p. 254, 1782. ' In the Bynonymy of Donax. Dall gives "Serrula Morch. Cat. Yoldi. ii., p. 18, 1853. Type D. trunculus (L.) Hanley." Since Morch, in his catalogue referred to, made no mention of type, and none was constituted by monotypy, we have taken Dall's statement as a type designa- tion. Dall designated many types in this manner, although some of these designations are invalid for obvious reasons. In his "Revision de8 Donacid^es," Bertin used Serrula Chemnitz for D. trunculus and several other species, but he did not mention any type for the group. > Nautilus, Vol. 37. pp. 81-84, 1924. 380 San Diego Society of Natural History [ Memoirs This is the elongate, pointed Donax of southern California beaches. It is very differ- ent from the short, square-ended species, D. gouldii Dall. D. flexuosus Gould is a short, trigonal species very unlike either of the above, and it has been assumed that an error in locality accounts for Gould's attributing it to Santa Barbara. It may be a synonym of D. striatus Linnseus, of the West Indies. Donax navicula Sowerby, which was confused with caUforniciis by Carpenter, is somewhat elongate, but the posterior end is slightly constricted, giving it an almost beaked appearance. It is a southern shell. Donax puncta- tostriatus Hanley is a much larger shell of the Lower California coast. Donax gouldii Dall Plate 13, Figure 12 Donax obesus Gould, Proc. Boston Soc. Nat. Hist., Vol. 4, p. 90, November, 1851; Boston Journ. Nat. Hist., Vol. 6, pp. 394, 395, pi. 15, fig. 9, 1853; not Donax obesa d'Orbigny, Voy. Amer. Merid., Moll., 1846. Donax Isevigata Deshayes, Proc. Zool. Soc. London for 1854, p. .352; Reeve, Conch. Icon., Vol. 8, Donax, pi. 5, fig. 31, 1854; Sowerby, Thes. Conch., Vol. 3, Donax, p. 309, figs. 30-32, 1866; Bertin, Nouv. Arch. Mus. Hist. Nat. Paris, Vol. 4, p. 91, 1881; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 969, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 170, pi. 13, fig. 8, 1903; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 47, pi. 16, fig. 2, 1920; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 252, 253, 254, 255, 1929; not Donax Isevigata Gmehn, Syst. Nat., Ed. 13, p. 3265, 1791. "Donax californicus Conrad," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 640, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 238, 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 186, 1892; not Donax californica Conrad. Donax gouldii Dall, U. S. Nat. Mus., Bull. 112, p. 49, February 24, 1921; Strong, Nautilus, Vol. 37, p. 83, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 183, pi. 49, figs. 8, 9, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Shell small, smooth, short, rather abruptly truncated posteriorly, margins of valves finely crenu- lated. Length, 15 to 20 mm.; height, 10 to 14 mm. Type localities: Of obesus Gould, San Diego, Recent; of Icevigatus Deshayes, unknown; of gouldii, Dall, presumably California; Recent. Pleistocene: Lower San Pedro series at San Pedro and Deadman Island, rare; Barlow's Ranch, near Ventura (Arnold); "Saugus" near Ventura (Waterfall); Pleistocene of Spanish Bight, Crown Point or Bay Point, Pacific Beach, and Torrey Pines, San Diego (Frank Stephens); foot of Twenty-sixth Street, San Diego; common in the upper San Pedro series at San Pedro, Los Cerritos, Crawfish George's, Long Beach, and Deadman Island, Los Angeles County (Arnold). Recent: Santa Barbara, California, to Acapulco, Mexico (Dall, 1921). This is the common, small, square-ended species of southern California beaches. It has a very restricted habitat between tides, occurring in a narrow zone on the clean sandy beaches where it may be gathered by the thousands during low and mid-tide. Gould's specific name obesus had been used by d'Orbigny in 1846. Although the habitat of Donax Icevigatus Deshayes was not given when described, the figure in the Conchologia Iconica suggests that the name was applied to the present California species. However, the name was used by Gmelin in 1791 for an entirely different shell from Madras, India (Tranquebar). This latter species is figured by Chemnitz.^ Donax cali- fornicus Conrad, confused by Carpenter, Cooper, and others (but not by Arnold) with the present species is very distinct. While we have not seen the type specimens of these species, the type figures or authentic illustrations indicate a significant difference. It is not unlikely that a name older than gouldii can be found for this species. ' Neucs Syst. Conch. Cab., Vol. 6, p. 253. pi. 25, fig. 249, 1782. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 381 Donax punctatostriatus Hanley Donax punctatostrialtis Hanley, Proc. Zool. Soc. London for 1843, p. 5, 1843; Rec. Shells, p. 84, pi. 14, fig. 24, 1844; Reeve, Conch. Icon., Vol. 8, Donax, pi. 3, fig. 16, 1854; Sowerby, Thes. Conch., Vol. 3, Donax, p. 310, sp. 33, figs. 49, 50, 1866; Bertin, Nouv. Arch. Mus. Hist. Nat. Paris, Ser. 2, Vol. 4, p. 95, 1881. Donax punctatoslriata Hanley, Dall, U. S. Nat. Mus., Bull. 112, p. 49, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Shell large, obliquely triangular with rather sharp angles; radially striate. Type locality: Mazatlan, Mexico; Recent. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Lower California, Mexico, to Peru. It is probable that this species does not extend so far north as San Pedro, California, which was given as the northern limit by Dall. Donax conradi Deshayes Donax conradi Deshayes, Proc. Zool. Soc. London for 1854, p. 351; Reeve, Conch. Icon., Vol. 8, Donax, pi. 5, fig. 29, 1854; Sowerby, Thes. Conch., Vol. 3, Donax, p. 310, sp. 34, fig. 51, 1866; Bertin, Nouv. Arch. Mus. Hist. Nat. Paris, Ser. 2, Vol. 4, p. 92, 1881; Dall, U. S. Nat. Mus., Bull. 112, p. 49, 1921; E. K. Jordan, Bull. So. CaUf. Acad. Sci., Vol. 23, p. 149, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 184, 1924. "Donax contusus Reeve," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 241, etc., 1864, doubtfully of Reeve, Conch. Icon., Vol. 8, Donax, pi. 4, fig. 24, 1854, Mazatlan. "Donax culler Hanley," Carpenter, op. cit., 1864, not, or doubtfully, of Hanley, Proc. Zool. Soc. London for 1845, p. 14, 1845. Shell large, radially striate, somewhat like that of D. punctatostriatus Hanley, but more elongate. Length, 27 mm.; height, 17 mm. Type locality: Gulf of California; Recent. Pleistocene: Lower Quaternary of Magdalena Bay, Lower Cahfornia, Me.xico (Jordan). Recent: San Diego, California, to Central America (Dall). Family SANGUINOLARIIDAE Genus GARI Schumacher, 1817 Gari Schumacher, Ess. Nouv. Syst. Habit. Vers Test., pp. 44, 131, 1817; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 461, 1846; H. and A. Adams, Gen. Rec. Moll., Vol. 2, pp. 389, 390, 1856; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Vol. 3, p. 113, 1871; Bertin, "Revision des Garidees," Nouv. Arch. Mus. Hist. Nat. Paris, Ser. 2, Vol. 3, p. 103, 1880; Harris, Cat. Tert. Moll. Brit. Mus., Pt. 1, p. 377, 1897. Psammobia Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 511, 1818; Bucquoy, Dautzenberg, and DoUfus, Moll. Mar. Roussillon, Vol. 2, p. 478, 1895; Dall, Proc. Acad. Nat. Sci. Phila., p. 57, 1898; Trans. Wagner Inst. Sci , Vol. 3, pp. 972, 974, 1900. Type (by absolute tautonymy), Gari vulgaris Schumacher (= "Tellina" gari Lin- naeus, Spengler = "Psartunobia" ccerulescens Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 51.3, 1818, at least in part; Reeve, Conch. Icon., Vol. 10, Psammobia, sp. 60, 1857); East Indies, Philippines, Orient. Shell elongate-ovate, generally rather thin, equi valve; hinge with one or two bifid teeth in each valve, part or all of one or more teeth sometimes being obsolete or much reduced; pallial sinus large; sculpture absent or of moderate strength, radial or concentric. As Schumacher's name Gari has priority over Psammobia Lamarck, 1818, the latter must be considered a synonym. Schumacher included but two species in the original List of species of Gari, the first, which he figured (pi. 9, fig. 2), being Gari vulgaris, a new name for "Tellina gari Lin. Spengl. [Nat. Hist. Selsk. Skr.] 4. H. 2, pag. 70, No. 1, Chemn. 382 San Diego Society of Natural History [ Memoirs [Neues Syst. Conchyl. Cab. Vol.] 6, pag. 100, Tab. 10, fig. 92. 93."' The other species, Gari papyracea (not figured by Schumacher), attributed to Spengler, is a Tellina and need not be considered here. The specific name "gari," although appearing in the synonymy, makes the first species "type by absolute tautonymy." In 1758, Linnaeus described a Tellina gari, taking the name from Rumphius's use of it in 1704. This Tellina gari Linnaeus, 1758, is obscured in doubt, as pointed out by Bertin- and others. DalP assumed that the T. gari Linnaeus of Schumacher was not the gari of Linnaeus, 1758, but of Linnaeus, 1762 (? Syst. Nat., Ed. 11). < Fortunately, Schumacher's reference to Chemnitz settles the uncertainty, for although the latter author {op. cit., p. 101) figures two different species (pi. 10, figs. 92, 93), he states that figure 92 represents Tellina gari Linnaeus from Speng- ler's collection, which unquestionably was the one Schumacher had in mind when he referred to Spengler. From a careful comparison of the figure given by Schumacher with Chemnitz's figure 92 and specimens of Gari carulescens (Lamarck) from the Philippines, we feel confident that the latter species was the one figured by Schumacher (pi. 9, fig. 2), and by Chemnitz in figure 92. Schumacher's figure is only of the interior, but it exactly matches specimens of coerulescens, except that the figure represents a slightly larger, more mature individual than any of the specimens we have examined. Chemnitz's figure 93 is almost certainly Gari amethysta (Wood) (described as Solen amethystus) .'• Section Gobraeus Leach, 1852 Gari califomica (Conrad) Psammobia califormca Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 4, p. 121, 1S49 (figured in the Journal, Vol. 7, pi. 19, fig. 3, 1837, without name or description); Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 45, pi. 14, fig. 1, 1920. Sanguinolaria rubro-radiata Conrad, Carpenter, Proc. Zool. Soc. London, Pt. 24, p. 212, 1856. Sanguinolaria nibroradiata Conrad, Nutt. MS., Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 195, 1857. Psammobia nibroradiata Nuttall, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 540, 563, 602, 638, 1864. Psammobia nibroradiata (Nutt. MS.), Carpenter, Proc. Acad. Nat. Sci. Phila. for 1865-66, p. 55. Gobranis califoniicus Conrad, Ball, Acad. Nat. Sci., Phila., Proc. for 1898, p. 58; U. S. Nat. Mus., Bull. 112, p. 49, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 7, 1925. Psammobia (Gobraeus) califomica Conrad, I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 1, p. 185, pi. 43, fig. 5, 1924. Type locality: California; Recent. Pliocene: Elsmere Canyon, Los Angeles County (one specimen in collection of Los Angeles Museum). Pleistocene: Lower San Pedro fauna of Nob Hill cut at San Pedro (T. S. Oldroyd). Recent: Japan, Kamchatka, the Aleutian Islands and south to San Diego, California (Dall, 1921). Psammobia rubroradiata Carpenter is apparently a synonym of Gari califomica (Conrad). A careful search of the literature convinces us that Conrad never described a rubroradiata in this genus. Carpenter gave a brief description of it in 1864 (p. 638) and an ample diagnosis in 1865 (or 1866). Gari califomica (Conrad) probably ranges south of San Diego in deeper water. Gari edentula (Gabb) Plate 21, Figure 5 "f Siliquaria" edentula Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 53, pi. 15, fig. 11, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 264, 1888. Gobrsms edentulus Gabb, Dall, Acad. Nat. Sci. Phila., Proc. for 1898, p. 58; U. S. Nat. Mus., Bull. 112, p. 49, 1921. ' The quotation marks include matter from Schumacher terbatim: the brackets include added data. ' Op. eit., p. 112. 1880. « Op. cit., p. 970, 1900. < Dall gives "Linn^, 1762" probably referring to the llth edition, which we have not been able to consult. Bertin gives a reference to the 12th edition, 1768. • Gen. Conch., p. 138, pi. 34, fig. 1, 1815. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 383 Psammobia {Psammohia) edentula Gabb, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 168, 1903. Psammobia edentula Gabb, English, Univ. Calif. Publ. Geo!., Vol. 8, p. 210, 1914; Nomland, Vol. 10, pp. 220, 301, 1917. Psammobia (Gobrs^us) edentula Gabb, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 185, pi. 57, fig. 1, 1924. Type locality: San Fernando, Los Angeles County; Pliocene. Miocene: Santa Margarita formation, upper Miocene, of middle California, questionably identified (Nom- land). Pliocene: Lower Fernando, lower Pliocene, of Holser Canyon, Los Angeles County (English); San Fernando (Gabb; Cooper); lower Fernando (Nomland). Pleistocene: Upper San Pedro series of San Pedro, rare, three good specimens (.\rnold). Recent: San Pedro and Catalina Island to San Diego, California (Dall, 1921). This species is larger and more elongate than G. californica Conrad. Genus SANGUINOLARIA Lamarck, 1799 Sanguinolaria Lamarck, Prodrome, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 84, 1799, only species Solen sanguinolenttis Gmelin; Berlin, Nouv. .\rch. Mus. Hist. Nat. Paris, Ser. 2, Vol. 3, pp. 81-83, 1880; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 972, 978, 1900. Lobaria Schumacher, Ess. Nouv. Syst. Hab. Vers Test., p. 122, 1817. Type (by monotypy), Solen sanguinolenius Gmelin;' Antilles; Recent. Section Nuttallia Dall, 1898 Sanguinolaria nuttallii Conrad Plate 20, Figures 15a, 156 Sanguinolaria nuttallii Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 230, pi. 17, fig. 6, 1837; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 638, 1864; Keep, West Coast Shells, p. 198, fig. 170, 1888, 1892; Dall, Proc. Acad. Nat. Sci. Phila. for 1898, p. 58; Clark, Univ. Calif. Publ, Geol., Vol. 8, p. 420, 1915; Nomland, Vol. 10, p. 220, 1917; Wej-mouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 46, pi. 14, figs. 2, 3, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 50, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 185, pi. 55, figs. 1, 4, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925. Psammobia decora Hinds, Ann. Mag. Nat. Hist., Vol. 10, p. 81, pi. 6, fig. 1, October, 1842; Zool. Voy. Sulphur, Moll., p. 66, pi. 19, figs. 6, 7, 1844. Hiatula nuttallii Conrad sp., Bertin, Nouv. Arch. Mus. Hist. Nat. Paris, Ser. 2, Vol. 3, p. 90, 1880. Sanguinolaria (XuttaUia) nuttaUii Conrad, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 168, 1903. Sanguinolaria (Nuttallia) orcutti Dall, West American Scientist (San Diego), Vol. 19, no. 2, p. 17, 1921; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 26, pi. 12, figs. 1, 2, 1925. Sanguinolaria orcutti Dall, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, pp. 244, 249, 2.50, text fig. 1, 1926. Type specimens: Of nuttallii, location unknown to us; of orcutti, in U. S. National Museum, No. 333,118. Type localities: Of nuttallii and decora, San Diego, California, Recent; of orcutti, San Quintin Bay, Lower California, Mexico, Pleistocene. Miocene: Upper part of San Pablo formation, upper Miocene of middle California (Clark). Pliocene: Etchegoin (Clark) ; rare in the Pecten coalingensis zone, Etchegoin formation of the Coalinga region (Nomland). Pleistocene: Lower San Pedro fauna of Nob Hill cut at San Pedro, not rare (T. S. Oldroyd) ; San Quintin Bay, Lower California, Mexico, as orcutti (Dall; Jordan); rather rare in the upper San Pedro series at San Pedro and Los Cerritos (Arnold). Recent: San Pedro, California, to Magdalena Bay, Lower California, Mexico; questionably Japan (Dall, 1921). This is the type of the Section Nuttallia Dall. ' Syst. Nat., Ed. 1.3, p. 3227, 17S8; figxired by Reeve, Conch. Icon., Vol. 10, Sanguinolaria, pi. 1, fig. 4, 1857. Bertin, op. cit., p. 83, gives the synonymy and a discussion of this species. Solen fucatus Spengier, the type of Lobaria Schumacher, is a synonym of S. sanguinolenius Gmelin, making Schumacher's genus an exact synonym of Lamarck's. 384 San Diego Society of Natural History [Memoirs Sanguinolaria orcutti Dall is not specifically distinct from nuttallii. The supposed differences in size and development of the anterior cardinal tooth do not occur in such a way as to suggest a valid difference. Dall's form has been reported abundant in the upper Pleistocene throughout the deposit at San Quintin Bay. In the upper Miocene of California Sanguinolaria alata (Gabb) is reported.' San- guinolaria townsendensis Clark- was described from the Oligocene of Washington. Genus TAGELUS Gray, 1847 Tagelus Gray, Proc. Zool. Soc. London, Pt. 15, p. 189, 1847; Dall, Proc. Acad. Nat. Sci. Phila. for 1898, p. 59; Trans. Wagner Inst. Sci., Vol. 3, pp. 981, 982, 1900. Type (by original designation), Solen guinensis Gray, figured in Reeve, Conch. Icon., Vol. 19, Solen, sp. 15, pi. 4, fig. 15, 1874, Guinea, west coast of Africa; Recent. Beaks median or sub-posterior; teeth two in each valve, simple, pedunculate; valves without constriction or clavicle, straight; pallial smus deep, reaching to or beyond the beaks; posterior ad- ductor scar rounded; palhal sinus with the ventral part partially coalescent with the pallial line; situs estuarine or marine (Dall, 1900) . Tagehis Gray has a number of synonyms which have been given by Dall (1900) and need not be repeated here. The anatomy has been described by Bloomer.' Tagelus califomianus (Conrad) Plate 21, Figures 2a, 26, 3 Solecurtus {Cultellus) califomianus Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 233, pi. 18, fig. 3, 1837. Solecurtus califomianus Conrad, Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 296, 1874; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 265, 1888; Keep, West Coast Shells, p. 201, fig. 172, 1888, 1892. Tagdus califomianus Conrad, Dall, Acad. Nat. Sci. PhUa., Proc. for 1898, p. 59; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 169, 1903; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 48, pi. 15, fig. 1, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 50, 1921; E. K. Jordan, BuU. So. Calif. Acad. Sci., Vol. 23, pp. 149, 152, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 186, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 479, 1926; Stephens, Trans. San Diego Soc. Nat. ffist.. Vol. 5, pp. 251, 255, 1929. Tagelus calif (rrnicas Conrad, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pliocene: Coyote Mountain, western Imperial County (Hanna); San Diego well, Balboa Park, San Diego (Dall, 1874). Pleistocene: Santa Barbara; San Pedro; San Diego (Cooper); lower San Pedro series at Deadman Island and San Pedro, rare (Arnold) ; lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan) ; "Saugus" near Ventura (Waterfall); upper San Pedro series at Deadman Island, Los Cerritos, Crawfish George's, San Pedro, and Long Beach, common (Arnold); foot of Twenty-sixth Street, San Diego (Arnold; Stephens); also two miles north of Del Mar, San Diego County (Stephens); upper Quaternary of Scammons Lagoon, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to Gulf of Tehuantepec (Dall). Tagelus violascens (Carpenter) Solecurtus violascens Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 27, footnote, 1857. Tagelus violascens Carpenter, Dall, Acad. Nat. Sci. Phila. for 1898, p. 59. Tagelus violacens Carpenter, Dall, Nautilus, VoL 32, p. 24, 1918. Type specimen: In the British Museum. Type locality: Southwest Mexico. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 1918). Recent: Gulf of California to Nicaragua (Dall, 1898). ' Clark, Univ. Calif. Publ. Geol., Vol. 8, pp. 476, 477, pi. 61, fig. 14, pi. 62, fig. S, 1915. » Univ. Calif. Publ. Geol., Vol. 15, p. 97, pi. 18, fig. 7, 1924. ■ Proc. Malac. Soc. London, Vol. 7, pp. 218-223, pi. 19, 1907. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 385 Section Mesoplkuha Conrad, 1867 Mesopleura Conrad, "Cat. Solenidss" Amer. Journ. Conch., Vol. 3, Appendix, p. 23, 1S67, Solen divisius Spengler; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 984, 1900. Shell with an internal radial rib, ventrally directed from the submedian beaks; ends of the valves rounded, and the form of the shell usually more or less arcuate; otherwise, like Tagelus. (Dall, 1900.) Tagelus subteres (Conrad) Solecurtus (CuUellus) subteres Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 233, pi. 17, fig. 10, 1837. Tagelus subteres Conrad, Dall, Acad. Nat. Sci. Phila., Proc. for 1898, p. 60; U. S. Nat. Mus., Bull. 112, p. 50, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 187, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type locality : Near Santa Barbara, California. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to Panama (Dall, 1921). Superfamily Solenacea Family SOLENIDAE Genus SOLEN Linnaeus, 1758 Solen Linnaeus, Syst. Nat., Ed. 10, p. 672, 1758; Children, Quart. Journ. Sci., Lit., and Arts, p. 83, pi. 4, fig. 26, Oct., 1822; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 949, 951, 1900. Type (by subsequent designation, Children, 1822), Solen vagina Linnseus. Shell long, approximately straight, dorsal and ventral margins parallel, beaks anterior, valves gaping at each end ; hinge with one cardinal in each valve. Solen sicarius Gould Plate 21, Figure 4 Solen sicarius Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 214, 1850; U. S. Expl. Exped. (Wilkes), Vol. 12, p. 287, 1852, Atlas, fig. 501, 1856; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 265, 1888; Keep, West Coast Shells, p. 202, fig. 173, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 172, 1903; Arnold, U. S. Geol. Surv., Bull. 396, p. 164, pi. 29, fig. 4, Jan. 15, 1910; Bull. 398, pi. 51, same figure, 1910; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 493, 494, 1913; English, Univ. Calif. Publ. Geol., Vol. 8, pp. 209, 211, 214, 1914; Clark, Vol. 8, p. 420, 1915; Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 32, 1916; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 229, 1916; NomJand, Vol. 10, p. 220, 1917; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 281, pi. 26, fig. 1, pi. 50, 1918; Weymouth, Calif. Fish and Game Comm., Fish BuU. No. 4, p. 50, pi. 15, fig. 2, 1920; Dall, U. S. Nat. Mus. Bull. 112, p. 50, 1921; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 188, pi. 49, fig. 1, pi. IS, fig. 1, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type locality: Strait of Juan de Fuca; Recent. Miocene: Montesano formation of western Washington (Weaver); ? Empire formation of Coos Bay region, Oregon; San Pablo formation, upper Miocene, of middle California (Clark); Walnut Creek, Contra Costa County (Cooper); Santa Margarita formation (Arnold). Pliocene: Lower Merced; Purisima; Etchegoiu Pliocene (Martin; Nomland; etc.) ; upper WUdcat formation of northern California (Martin); Merced formation of Sonoma County (Dickerson); Twelve Mile Creek, San Mateo County; also San Fernando, Los Angeles County (Cooper); lower Fernando of Elsmere, Holser, and Pico canyons, and east of mouth of Little Tujunga Canyon (English) ; Pico near Ventura (Waterfall). Pleistocene: "Pliocene" of Deadman Island and Timm's Point, and common in the lower San Pedro series of Deadman Island and San Pedro (Arnold, 1903); Nob Hill cut, San Pedro (T. S. Oldroyd) ; "Saugus" near Ventura (Waterfall) ; lower Quaternary at Magdalena Bay, Lower California, Me.\ico (Jordan) ; upper San Pedro at Los Cerritos, San Pedro, Crawfish George's, and Deadman Island, rare (Arnold, 1903) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Vancouver Island, British Columbia, to San Quintin Bay, Lower California, Mexico (Dall, 1921). 386 San Diego Society op Natural History [Memoirs Professor B. L. Clark of the University of California states that the reports of the occurrence of S. sicarius in the Miocene and Pliocene undoubtedly refer to the variety perrini, but as the collections upon which many of the records have been based are not now available, we have merely tabulated the data as published, until a careful review of the Pacific coast species of this genus can be made. Solen sicarius Conrad variety perrini Clark Solen perrini Clark, Univ. Calif. Publ. Geo!., Vol. S, pp. 420, 477, 47S, pi. 44, fig. 2, 1915; Xomland, Vol. 10, p. 301, 1917. Type specimen: In the University of California collection. Type locality: Middle California; San Pablo group, upper Miocene. Miocene: Scutella breweriana zone, Briones formation, lower part of upper Miocene; San Pablo group and Santa Margarita formation, upper Miocene, middle California (Clark); Santa Margarita formation north of Coalinga (Nomland). Pliocene: Jacalitos and Etchegoin formations (Clark). According to Clark: "This species sometimes has a length of six to eight inches and a height of from one inch to one and one-half inches. It is the most common Solen in the Miocene and Pliocene of California. It has been listed by various writers as Solen sicareus Gould and Solen rosaceus Cpr. It differs from S. sicareus in that both the posterior dorsal edge and the ventral edge are straight. S. sicareus shows a slight concavity along the posterior dorsal edge, while the ventral edge is slightly convex. Also S. sicareus has very little, if any, flexure on the anterior end. *S. perrini resembles S. rosaceus more closely than S. sicareus. It differs in that it is a heavier shell ; and it is higher in proportion to its length." Solen rosaceus Carpenter Solen (sicarius ? var.) rosaceus Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 638, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 177, 1865. Solen rosaceus Carpenter, Gabb, Geol. Surv. Calif., Palso., Vol. 2, p. 88, 1868-9; Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 296, 1874; Cooper, 7th .\nn. Rept. Calif. State Mineralogist, p. 265, 1888; Dall, Proc. U. S. Nat. Mus., Vol. 22, p. 108, 1899; Trans. Wagner Inst. Sci., Vol. 3, p. 952, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 38, 171, 1903; Wejonouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 50, pi. 15, fig. 3, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 50, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 188, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Miocene: Tomales, Marin County; Martinez, Contra Costa County (Cooper). Pliocene: Santa Rosa, Sonoma County; San Ramon, Kirker's Pass, Contra Costa County; San Fernando, Los Angeles County; San Diego well (Cooper); San Diego well in Balboa Park, San Diego (Dall). Pleistocene: Santa Barbara (Cooper); rare in lower San Pedro series of Deadman Island and San Pedro bluffs; Spanish Bight, San Diego; rare in the upper San Pedro of Deadman Island and Crawfish George's (Arnold) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to the Gulf of California, Mexico (Dall, 1921). This species is longer, narrower, more nearly cylindrical, and has a more rounded anterior extremity than *S. sicarius Gould. Genus SILIQUA Megerle von Milhlfeld, 1811 Siliqua Megerle von Miihlfeld, Gesellschaft Naturforschender Freunde, Magazin, p. 44, 1811; Gray, Proc. Zool. Soc. London, p. 189, 1847; Herrmannsen, Indicis Gen. Malac, Vol. 2, p. 454, Feb. 18, 1848; DaU, Proc. U. S. Nat. Mus., Vol. 22, p. 108, 1899; Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 955, 1900. Leguminaria Schumacher, Ess. Nouv. Syst. Hab. Vers Test., p. 126, 1817, type (by monot)T5y) L. costata Schumacher, pi. 7, fig. 1, = S. radiata (Linnaeus). Machsera Gould, Invert. Mass., p. 32, 1841, not Machssra Cuvier, 1832. Volume I ] PlIOCENE AND PLEISTOCENE AIOLLUSCA OF CALIFORNIA 387 Type (according to Gray, Herrmannsen, Dall, etc.), Solen radiatus Linnaeus, Syst. Nat., Ed. 10, p. 673, 1758, illustrated by Sowerby in Reeve, Conch. Icon., Vol. 19, Cultellus, pi. 4, species 13, 1874, living, Sumatra. Shell of nipdium or large size, relatively tliin, almost flat, elongate, with nearly parallel margins and rounded ends; marked l:)y concentric growth lines and annular rings, and usualh' with hroad, radiating color l)ars; hinge usually about a third of tlie distance from the anterior end, left hinge with two small sharp cardinal teeth close together and with one and the remnants of a second spur-like posterior tooth, right hinge with one sharp cartlinal tooth and one thin wedge-like posterior tooth; posterior dorsal margins strongly reinforced under the areas of attachment of the ligament, behind which they are abruptly slit as in Macoma secta; interior of each valve marked by a transverse strengthenmg rib that runs from the hinge toward the ventral margin a little in front of the vertical, dying out gradually before it reaches the margin, pallial sinus large, rounded, reaching from the posterior quarter about to the middle of the shell. Geologic range: Cretaceous to Recent (Pacific United States). Distribution : Arctic and temperate regions generally, although the type comes from Sumatra. This well-marked genus is like Cultellus except that the latter lacks the internal rib. It is distinguished from other genera in the Solenidce by the presence of this internal rib, and usually also from Solen, Ensis, and Tagelus by its deeper shell. Iredale has shown that Solecnrtus Blainville is not a synonym but takes the place of Psavimosolen. Siliqua patula (Dixon) Cf. Plate 21, Figure 9 Solen palulus Dixon, Voyage Round tlie World, p. 355, figs. 2, 1789. Solen maiimus W'ood, General Conchology, Vol. 1, p. 129, pi. 31, fig. 3, 1815, not of Gmelin, 1792. Solen gigas Dillwyn, Cat. Shells, p. 61, 1817. Solecnrtus nullaUii Conrad, Journ. Acad. Nat. Sci., Vol. 7, p. 232, pi. 17, fig. 9, 1837. Siliqua splendens Chenu, 1845 (fide Dall); Chenu, Man. Conchyl., Vol. 2, p. 23, fig. 103, 1862. ? Siliqua americana Chenu, 1845 (questionably referred here by Dall). Siliqua grandis "Gmelin," Dunker, Carpenter, etc. ( fide Dall) ; there is no grandis of Gmelin. Machsera patula Di.xon, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 601, 638, etc., 1864, reprinted, Smithsonian Inst. Misc. Coll. No. 252, pp. 87, 124, etc., 1872; Gabb, Geol. Survey Calif., P.alffiO., Vol. 2, p. 89, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 248, 1888; Keep, W'est Coast Shells, p. 201, fig. 171, 1888, 1892. Siliqua calif oruica Conrad, .\mer. Journ. Conch., Vol. 3, p. 193, 1867 (fiide Gabb). Siliqua patula Di.xon, Conrad, Amer. Journ. Conch., Vol. 3, Appendix, p. 25, 1868; Dall, .\mer. Journ. Conch., Vol. 7, p. 140, 1871; Proc. U. S. Nat. Mus., Vol. 22, p. 109, 1899; Keep, West Amer. Shells, p. 92, fig. 82, 1904; Bloomer, Proc. Malac. Soc. London, Vol. 6, pp. 193-195 (anatomy), pi. 12, 1905; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 254, 1916; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 50, pi. 15, fig. 4, 1920; Dall, Bull. 112, U. S. Nat. Mus., p. 51, 1921; Meek, Univ. Calif. Publ. Geol., Vol. 14, pp. 414, 418, 1923; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 190, pi. 48, pi. 52, fig. 1, 1924. Cultellus nutlali Conrad, Sowerby in Reeve, Conch. Icon., Vol. 19, Cultellus, pi. 3, species 11, 1874. Siliqua patula var. nuttallii Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 22, p. 109, 1899; .\rnold, Mem. Calif. Acad. Sci., Vol. 3, p. 173, 1903; Dall, Bull. 112 U. S. Nat. Mus., p. 51, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 190, pi. 18, figs. 2a, 26, 1924. Siliqua nuttallii Conrad, Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 956, 1900; Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 229, 232, 233, 239, 243, 245, 254, 1916; Arnold and Hannibal, Proc. Amer. Phil. Soc, Vol. 52, pp. 590 (+ oregonia Dall), 593, 596, 1913; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 281, pi. 26, figs. 2a, 2b, 1918; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922. Siliqua (patula Dixon var.?) oregonia Dall, Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 957, 1900. Shell large, altitude about four-ninths the length, beaks at about the anterior third, dorsal mar- gins sloping away from them slightly, the anterior more than the posterior, anterior end strongly curving, posterior end somewhat truncated, lioth ends gaping, ventral margin nearly straight, some- times bent in the middle, the posterior end of the shell sometimes slightly narrower; surface covered 388 San Diego Society of Natural History [ Memoirs with a greenish epidermis, thin and yellow-green on smaller and more southerly specimens, heavy and brownish-green on old specimens or specimens that have lived in exposed or northerly localities, marked by concentric growth lines which show annual rings of different color or frequency, the northern specimens adding a narrower ring each year but living longer; hinge normal, the interior rib broad, low, sloping diagonally forward. Dimensions : Length, 154 mm. ; altitude, 67 mm. ; convexity of the two valves, 28 mm. Type specimens: Of patula, in the Swainson Collection {fide Oldroyd), London (?); of the other names by European authors, probably London or Paris; of nuttallii and ameri- cana, in the Academy of Natural Sciences, Philadelphia (?) ; of oregonia Dall, either in Philadelphia or in U. S. National Museum. Type localities: Of patula, from Cook's River, Alaska; of nuttallii, inhabiting "salt marshes, somewhere towards Point Adams, in the estuary of the Columbia;" of californica, Bodega Bay, middle California; of oregonia, Empire formation, upper Miocene near Coos Bay, Oregon. V. Miocene: Type locality of oregonia (Dall; Arnold and Hannibal; Howe). Pliocene: Merced-Purisima formation of middle California (Arnold and Hannibal; Martin); Wildcat forma- tion of northern California (Martin); Etchegoin of the San Joaquin basin, California (Martin); ? from a depth of 4450-68 feet in the General Petroleum Stiles well at McFarland, Kern Co., about a dozen specimens (H. R. G.). Pleistocene: Rare in the upper San Pedro of San Pedro and of Spanish Bight, San Diego (Arnold) ; Pleistocene of Peard Bay, northern Alaska (Meek). Living: Arctic Ocean to Monterey Bay, California. This species, well known as the edible razor clam, has been thoroughly studied by the Fish Commission.' Thousands of specimens have been examined, their characters and habits analyzed, and the conclusion reached that the differences between the northern form (patula) and the southern form (nuttallii) are environmental, not genetic. Thus these two names must be considered absolutely synonymous. It is, nevertheless, worth while to note that the cold climate of the north causes the northerly individuals to grow more slowly, though they live longer and in the end attain a larger size, having a some- what different, more weather-beaten appearance than their southern brothers. On the other hand, the form alta, usually considered a variety of patula, is shown to be a distinct and clearly recognizable species. It is distinguished by its gi'eater proportionate altitude, increasing posteriorly, by its short anterior end, both of its ends being much blunter, and by the fact that the internal rib runs from the hinge nearly straight across the shell. The young of patula are difficult to distinguish from lucida. However, the latter has a thinner shell, the internal rib is higher, sharper, and narrower, running straight across the shell, and the posterior end is blunter. The Pliocene specimens of patula look more like the Atlantic costata (Say), 1822, not (Schumacher), 1817, = nahantensis (Des- moulins), 1832, with which they may have had a common origin. It is even possible that the Pliocene specimens should be recognized as nahantensis, but the material is not well enough preserved to make certain identification possible. Siliqua alta (Broderip and Sowerby) Plate 21, Figure 1 Solen altus Broderip and Sowerby, Zool. Journ., Vol. 4, p. 362, 1829. ? Solen 7nedius G. B. Sowerby, Zoology of Beechey's Voyage in the "Blossom," p. 153, pi. 46, fig. 2, 1839. Siligua media "Gray," Dall, Amer. Journ. Conch., Vol. 7^ p. 141, pi. 14, fig. 11, 1871 ; Bull. 112 U. S. Nat. Mus., p. 51, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 189, in part (not the description which is taken from the Conch. Icon.), 1924. 1 McMillin, H. C: "The Life History and Growth of the Razor Clam." pp. 1-52, ill., Olympia, Washington, 1924, in the 34th Ann. Ecpt., Supervisor of Fisheries of the State of Washington for 1923-24, 1925. Weymouth, F. W., McMillin, H. C, and Holmes, H. B.: "Growth and Age at Maturity of the Pacific Razor Clam, Siliqua patula (Dixon) ," Bull. Bureau Fisheries, U. S. Dept. Commerce, Vol. 41, pp. 201-236, ill., 1925. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 389 "CuUellus costatus Say," Sowerby in Reeve, Conch. Icon., Vol. 19, Cultellus, pi. 3, fig. 8, species 20, 1874. Not "CuUellus medius Gray," Sowerby in Reeve, Conch. Icon., Vol. 19, Ctdtellus, pi. 3, fig. 9, species 21, pi. 6, fig. 96, 1874 (fide Dall). Siliqua patula var. alta Broderip and Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 22, p. 109, 1899; Bull. 112 U. S. Nat. Mus., p. 51, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 190, pi. 47, figs. 1, 2, 1924. Shell of medium or large size, altitude alDOut half the length, beaks at about the anterior third ' anterior dorsal margm begiiming to round almost immediately and merging into the broadly rounding anterior end, posterior dorsal margin nearly straight for some distance and then slightly alate and bowing upward, posterior extremity very bluntly rounded, ventral margin nearly straight, the pos- terior end of the shell noticeably broader than the anterior; hinge teeth strong, interior rib broad, low, crossing the shell vertically. Dimensions: Length, 125 mm.; altitude at hinge, 54 mm., maximum at posterior end, 62 mm.; convexity of two valves, 27 mm. Type specimens: In the British Museum (?). Type localities: Of alta, Arctic Ocean; of media, Alaska (?). hiving: Arctic Ocean, south to Cook's Inlet, Alaska, and to the Okhotsk Sea. This species is similar to nahantensis (Desmoulins) from the Atlantic in that it has the vertical internal rib of the latter and about the same shape; but the adult is larger, relatively shorter, with blunter ends, and the posterior end broadens in a characteristic way, whereas that of nahantensis tapers off. Dall (1899, p. 108) gives the synonymy of nahantensis (+ costata Say not Schumacher). iS. alta is similarly distinguished from S. patula; and in addition, S. patula has a diagonal internal rib. The form figured by Dall as media and erroneously attributed to Gray, and Dall's description, together with a specimen in the Oldroyd Collection at Stanford University which was labeled by Dall in Washington, agree exactly with the young of /S. alta. The "Cultellus inedius" of Sowerby in Reeve is, according to Dall, the Atlantic S. squama Blainville, 1824. Siliqua lucida (Conrad) Plate 21, Figure 6 Solecurtiis lucidus Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, p. 231, pi. 17, fig. 8, 1837. Siliqua lucida Conrad, Dall, Amer. Journ. Conch., Vol. 7, p. 141, 1871; Proc. U. S. Nat. Mus., Vol. 22, p. 109, 1899; Trans. Wagner Inst. Sci., Phila., Vol. 3, p. 957, 1900; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 172, 1903; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 420, pi. 44, fig. 3, 1915; Nomland, Vol. 9, p. 203. 1916; Martin, pp. 239, 254, 1916; Moody, Vol. 10, p. 45, 1916; Nomland, pp. 212, 221, 301, .302, 1917; Dall, Bull. 112, U. S. Nat. Mus., p. 50, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 189, pi. .52, fig. 2, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Shell small, thin, elongate, beaks about a quarter of the distance from the anterior end, anterior end short and roimded, posterior dorsal margm nearly straight, posterior extremity blunt, ventral margm moderately convex; sculpture of fuie growth Imes and annual rings; hinge normal, mtemal rib sharp and narrow, undercut on the posterior side near the hinge, crossing the shell vertically; pallial sinus moderately deep, rounded. Dimensions : Length, 40 mm. ; altitude, 1 1 mm. ; convexity of two valves, 6 mm. Type specimen: In the Academy of Natural Sciences, Philadelphia (?). Type locality: Recent, near Santa Barbara. U. Miocene: San Pablo-Santa Margarita of middle California (Clark; Nomland, 1917). Pliocene: Lower Etchegoin and Jacalitos of the San Joaquin basin, common (Nomland, 1916, 1917) ; common in the basal marine Pliocene of the well cores of the Fruitvale district, near Bakersfield (H. R. G.) ; middle or upper Etchegoin of a depth of 3000-18 feet in the General Petroleum Co., Stiles well at McFarland, Kern Co., north of Bakersfield, fifty specimens (H. R. G.); middle Wildcat formation of northern Cahfornia (Martin); upper Pliocene of Fourth and Broadway, Los Angeles (Moody). Pleistocene: Lower and upper San Pedro series of San Pedro, Los Angeles Co., (.\rnold); 26th Street, and Spanish Bight, San Diego (Arnold); San Quintin Bay, Lower California (Jordan). Living: Monterey, California, to Todos Santos Bay, Lower California (Dall, 1921). 390 San Diego Society of Natural History [ Memoirs This species is clearly distinct from the others. It is smaller and so thin that the rib shows through plainly, even on fossil specimens. It has a more southerly modern distri- bution, and occurs farther south and in the warmer water horizons of the Tertiary. Young specimens of patula might be confused ; but lucida can be distinguished by its narrower and higher internal rib crossing the shell at right angles, by its shorter anterior extremity, by its blunter posterior extremity, and by its more arcuate ventral margin. Superfamily Mactracea Family MACTRIDAE Shell rounded-trigonal or elongate, equivalved, with or without a posterior gape; umljones in- clined forward; hinge normally with a bifid A -shaped cardinal in the left valve embraced by a simi- lar tooth in the opposite valve, sometimes with accessory tooth-like processes, and generally with well-developed lateral teeth; chondrophore posterior to the cardinals, rather prominent, excavated; ligament small, external or internal; jiallial sinus generally short and rounded. The Mactridce form a large group of smooth or concentrically sculptured, rounded- trigonal or elongate-ovate shells which are readily recognized by their prominent chon- drophores and bifid A-shaped cardinal teeth.' The family originated in the Mesozoic, a number of species having been recorded from the Cretaceous. The genera and subgenera of the Mactridce have been differentiated by the characters of the hinge. The position of the ligament has been the fundamental character in the subdivision of Mactra, sensu lato. Gray, in his Synoptical Catalogue of 1837^ and in a later important contribution,^ laid the foundation of a classification of the Mactridce which has been the basis of all subsequent work. Ball's discussions^ of the Mactras have been based upon Gray's pioneer work, and, as a whole, have added to our knowledge of the group ; but the contributions of his writings have been offset by the creation of some illogical subdivisions. More recently Packard'* published a well-illustrated paper on the Mesozoic and Ceno- zoic Mactrinw of the Pacific coast of North America in which much scattered information on Pacific coast species has been collected. In 1917 Lamy'' published a revision of the living Mactras in the Paris Museum, figuring many hinges and contributing information on the genera and species. Genus MACTRA Linnaeus, 1767 Mactm Linnseus, Syst. Nat., Ed. 12, p. ll'i.'i, 1767, list includes M. slidtorum: Gray, Loudon's Mag. Nat. Hist., New Series, Vol. 1, p. 371, 1837; Proc. Zool. Soc. London, Pt. 15, p. 18.5, 1847; Cossmann, Ann. See. Roy. Malac. Belg., Vol. 21, p. 60, 1886; Dall, Nautilus, Vol. 8, pp. 25, 26, 1894; Proc. Malac. Soc. London, Vol. 1, pp. 203-208, 211, 1895; Trans. Wagner Inst. Sci., Vol. 3, p. 874, 1898; Lamy, Journ. Conchyl., Ser. 4, Vol. 17, p. 176, 1917. Trigondla Da Costa, Hist. Nat. Test. Brit., p. 196, 1778. CrassatcUa Lamarck, M6m. Soc. Hist. Nat., Paris, Ser. 1, Vol. 1, p. 85, 1799. Type (by subsequent designation. Gray, 1847), Mactra stuUorum (Linnseus), Syst. Nat., Ed. 12, p. 1126, 1767; = Cardium stultorum Linnseus, Ed. 10, p. 681, 1758; figured by Reeve, Conch. Icon., Vol. 8, Mactra, pi. 4, fig. 15, 1854; see Lamy, op. cit., pp. 180-188, figs, on p. 177, 1917; European seas. 1 The cardinal tooth in the right valve appears to be the result of the coalescence at the top of two divereing teeth. ' Loudon's Magazine of Natural History, New Series, Vol. 1, no. 7. pp. 370-377, July, 1837. 3 Ann. Mag. Nat. Hist., Ser. 2, Vol. 11, pp. 41^4, January, 1853. > Nautilus, Vol. 8, pp. 26-28, 1894; Proc. Malac. Soc. London, Vol. 1, pp. 203-213, 1895; Trans. W.agner Inst. Sci., Vol. 3. pp. 862-916. 1895. s Univ. Calif. Publ. Oeol., Vol. 9, pp. 261-360, pis. 12-35. text figs.. May 1, 1916. " Journ. de Conchyliologie, ,Ser. 4, Vol. 17. pp. 173-275, 292-411. with many figures of hinges, including those of type species. 1917. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 391 Shell ovate-trigonal, generally almost equilateral; hinge with laterals well developed, a small spur sometimes projecting over the chondrophore from the cardinal margin. The differentiation of typical Mactra, Spisula, and Mulinia has been based largely on the position of the ligament. In Mactra, s. s., as typified by M. stultorum, the ligament, though very small, is clearly visible from the exterior. An umbonal view of a pair of matched valves discloses a small crack between and slightly posterior to the umbones. In fresh or living specimens the ligament occupies this space. A hinge view shows a very small, narrow shelly ridge separating the shelf-like ligamental pit from the chondrophoric cavity. The presence of this shelly ridge serves to distinguish Mactra, s. s., from Spisula. The hinge of Mactra solida (Linnseus), the type of Spisula, shows that the ligament, while still partly external, is not separated from the chondrophoric pit, the shelly process which separated the two in Mactra stultorum being absent. When the partition is absent in a specimen it is necessary to ascertain if it has been broken away by accident. Mulinia differs from both Mactra, s. s., and Spisula by having an entirely internal ligament. An umbonal view of two perfect, matched valves of Mulinia shows no crack or chink between the margins of the valves in the umbonal area, the ligament having descended into the resilial pit. Thus a study of the hinge of good specimens of Mactra, sensu lata, will permit the placing of the species in the proper subgenera. This character, the position of the ligament, although it may be of systematic value, does not appear to the writers to be entitled to more than subgeneric distinction; and accordinglj' Spisula and Mulinia have been treated here as subgenera of Mactra. Such an arrangement will often relieve the paleontologist of the necessity of guessing whether poorly preserved specimens belong to Spisula or to Mactra, since the name Mactra can be used for both, and the subgenus left undecided. Subgenus MACTRA, s. s. Hinge with a small external ligament m a slight depression separated from the chondrophore by a small shelly ridge. Lamy has figured the hinge of Mactra corallina (Linnteus), of which species he con- siders stultorum a variety {op. cit., figures on page 177). These figures are accurate and depict well the hinge characters of typical Mactra. Section Mactra, s. s. Shell ovate, moderately convex; lateral teeth long. Mactra (Mactra) orthomorpha, new species Plate 23, Figures 2a, 2b, 2c, 6, 7 Shell ovate-sub trigonal, moderately ventricose, of moderate thickness; umbones rather full, coming to a blunt pomt at the dorsal margms of the valves ; surface of valves marked with fhie, low, irregular growth lines and a low angulation running from the umbo to the posterior ventral margin; hinge normal, chondrophore prominent, wide, overhmig by a spur, lateral lammae rather long, well- developed, in the right valve a second set attached to the dorsal margin of the valve. Length, about 39 mm. ; height, about 32 mm. ; convexity of one valve, about 12 mm. Type specimen: S. D. S. N. H. No. 193. Type locality: Federal Exploration Company's well, Kinsella No. 1, depth 2794 feet. Sec. 15, T. 22, R. 24, near Tipton, Tulare Countj^ California; upper middle Etchegoin formation. Pliocene. 392 San Diego Society of Natural History [Memoirs This new species shows such a striking similarity to specimens of Mactra stultorum (Linnseus) from the Mediterranean Sea that it is difficult to believe that they are not closely related. In size, general shape, and in character of the hinge the two are prac- tically identical. The California species has a somewhat heavier shell, stronger lateral teeth, a larger chondrophore, and more prominent concentric growth Unes on the exterior of the shell. In the right valve of both species the anterior branch of the A-shaped car- dinal is partly coalescent above with the dorsal margin of the valve. Specimens labeled Mactra sachalinensis Schrenck' in the Oldroyd Collection at Stanford University (from Oshima, Japan), differ significantly only in size, the Japanese shells being very much larger (length, 89 mm.; height, 70 mm.). Mactra orthomorpha is entirely different from Mactra californica Conrad, which is a relatively much longer and less ventricose shell, with shorter lateral teeth. Conrad's species is also thinner shelled. "Mulinia" pabloensis Packard,^ of the upper Miocene of Contra Costa County, may be related to this new species. Packard's species is larger, has broader umbones and heavier laterals, which have transverse striations. It is not a Mulinia. Section Mactrotoma Dall, 1894 Mactroloma Dall, Nautilus, Vol. 8, p. 26, 1894; Trans. Wagner Inst. Sci., Vol. 3, p. 876, 1898. Type (by original designation, Dall, 1894), Mactra fragilis Gmelin; figured by Reeve, Conch. Icon., Mactra, sp. 47, pi. 11, fig. 47, 1854; and by Dall, Trans. Wagner Inst. Sci., Vol. 3, pi. 27, figs. 1, 4, 8, 18, 1898; also by Lamy, Journ. Conchyl., Ser. 4, Vol. 17, figs, on p. 179, 1917; North Atlantic, Recent. Shell elongate, sometimes of low convexity; laterals short. Mactra (Mactra) californica Conrad Mactra californica Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 240, pi. 18, fig. 12, 1837; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 876, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 174, pi. 19, fig. 2, 1903; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 151, 152, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 251, 1929; not Maclra californica Deshayes in Reeve, Conch. Icon., Vol. 8, Mactra, sp. 114, May, 1854; nor of Deshayes, Proc. Zool. Soc. London, Pt. 22, p. 68, February 10, 1855, for date, see Tomlin, Journ. Conch., Vol. 17, p. 134, 1924; not "Mactra californica Conrad," Reagan, Trans. Kansas Acad. Sci., Vol. 22, pi. 4, fig. 41, 1909. Mactra angusta Deshayes in Reeve, Conch. Icon., Vol. 8, Mactra, sp. 93, pi. 18, fig. 93, May, 1854; Deshayes, Proc. Zool. Soc. London, Pt. 22, pi. 67, Feb. 10, 1855. Mactra (Mactrotoma) californica Conrad, Dall, Nautilus, Vol. 8, p. 40, 1894; Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 280, pi. 16, figs. 4a-c, 1916; Lamy, Journ. Conchyl., Ser. 4, Vol. 17, pp. 251, 252, 1917; Dall, U.'S. Nat. Mus., Bull. 112, p. 51, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 192, pi. 20, figs. 4, 5, 6, 1924; Strong, Nautilus, Vol. 38, p. 99, 1925. "Spisula {Symmorphomactra) planulata Conrad," Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, pi. 17, figs. 4-6 only (reproductions of Packard's figures), 1924. "Mactra nasuta Gould," of some authors, not of Gould. Type locality: Santa Barbara, California; Recent. Pleistocene: Upper San Pedro series of San Pedro, "one specimen" (Arnold, 1903); Pleistocene of Santa Monica, one specimen (T. S. Oldroyd CoUeotion) ; foot of Twenty-sixth Street, San Diego, common (Arnold; F. Stephens) ; upper Pleistocene of San Quintin Bay, of San Ignaoio Lagoon and of Scam- mons Lagoon, Lower California, Mexico (Jordan, 1924, 1926). Recent: Neah Bay, Washington, to Panama. 1 Bull. Acad. Imp. Sci. St. Petersburg, Vol. 4, p. 412, October, 1861; MoUueken des Amurlandes und des Nordjapanischen Meeres, p. 575» pi. 23, figs. 3-7. « Univ. Calif. Publ. Geol., Vol. 9. p. 309. pi. 34, figs. 5, 6, 1916. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 393 This is the common small Mactra of southern California. It is rather flat, elongate, and the laterals are short and close to the cardinals and chondrophore. It is the type of Dall's section Micromactra.^ Mactra (Mactra) dolabriformis (Conrad) Spisula dolabriformis Conrad, Amer. Journ. Conch., Vol. 3, p. 193, 1867, as "Spissula," err. pro Spisula, corrected in appendix, p. 44. Mactra dolabriformis Conrad, Dall, Natuilus, Vol. 7, p. 138, pi. 5, fig. 1, 1894; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Mactra (Mactroloma) dolabriformis Conrad, Dall, Nautilus, Vol. 8, p. 40, 1894; Trans. Wagner Inst. Sci., Vol. 3, p. 876, 1898; Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 279, 1916; Dall, U. S. Nat. Mus., Bull. 112, p. 51, 1921: 1. S. Oldroyd, Stanford Univ. Publ. Geol,, Vol. 1, p. 191, 1924; Strong, Nautilus, Vol. 38, p. 100, 1925. Mactra (Simomactra) dolabriformis Conrad, Lamy, Journ. Conchyl., Ser. 4, Vol. 17, p. 263, 1917. Type locality: "Panama," according to Conrad; Recent. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: West coast of Lower California and the Gulf of California; Panama range denied by Dall, who re- ports the species from California; CaUfornia range questioned by the present writers. Mactra dolabriformis (Conrad), according to Strong,^ "is a rare species of which a few specimens have been dredged in southern California waters. The shell is much com- pressed, resembling Spisula falcata Gld., but with more central beaks, riiore elongate shape, and larger size, the adult three and a half to four inches in length." Mr. Strong is now of the opinion that the California shells may not belong to this species. M. dolabri- formis is the type of Dall's section Simomactra. ' Specimens of Mactra dolabriformis Conrad are similar in shape to Gould's type figures of M. falcata. Even the hinges are very similar except that dolabriformis has a strong shelly ridge between the hgament and the chondrophore, which places it in Mactra, s. s. Subgenus SPISULA Gray, 1837 Spisula Gray, Loudon's Mag. Nat. Hist., New Series, Vol. 1, p. 372, July, 1837; Proc. Zool. Soc. London for 1847, p. 185, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 895, 896, 1898; Lamy, Journ. Conchyl., Ser. 4, Vol. 17, pp. 291, 292, 1917. Type (by subsequent designation, Gray, 1847), Mactra solida (Linnaeus), Syst. Nat., Ed. 10, p. 681, as Cardium; hinge figured by Lamy, op. cit., figs, on p. 292, 1917. Hinge with a small external ligament in a depression not separated from the chondrophore by a shelly ridge. The small size of the Mactroid ligament and the difficulty of observing the small shelly ridge, particularly in fossil specimens, sometimes make the determination of the .subgeneric group to which a particular specimen belongs a difficult matter. In Spisula there is no sign of a shelly ridge between the chondrophore and the ligamental cavity. Section Spisula, s. s. Shell small or of moderate size, subtrigonal; beaks small, central, only slightly inchned forward; hinge with large laterals; rather small cardinals, and a moderate-sized chondrophore. ^ Dall, Nautilus, Vol. 8, p. 40, 1S94, only species Mactra {Mactroloma) califomica Conrad. 2 Op. cit., p. 100, 1925. 3 Nautilus, Vol. 8, p. 40, 1894, only species Mactra (Mactrotoma) dolabriformis Conrad. 394 San Diego Society of Natural History [ Memoirs Section Mactromeris Conrad, 1868 Maclromeris Conrad, "Cat. Mactridse," Amer. Journ. Conch., Vol. 3, Appendix, p. 45, 1868; Dall, Tran.s. Wagner Inst. Sci., Vol. 3, p. 878, 1898; Lamy, Journ. Conchyl., Ser. 4, Vol. 17, p. 293, 1917. Symmorphomactra Dall, Nautilus, Vol. 8, p. 41, IS94, type (by monotypy) M actra falcata Gould. Tijpe (by subsequent designation, Dall, 1898), M. polynyma Stimpson, Checklist Shells N. A., Smithsonian Misc. Coll., Vol. 2, Art. 6, No. 3, p. 3, 1860 (+ M. ovalis Gould, 1840, not J. Sowerby, 1817) ; figured by Lamy, op. cit., p. 293, 1917. Shell of moderate or large size, ovate, subtrigonal; lieaks more anterior than in Sp-is^da, s. s. ; hinge with relatively small, short laterals, an ample chondrophore, and cardinal teeth often small but well formed. The Pacific coast Mactras that have been placed in Heminiactra Swainson' do not belong there, unless the group is much enlarged in meaning to include species very far from the typical. Swainson characterized Hemimadra as being of the "general form of M actra; but the cardinal teeth entirely wanting." Examination of specimens of the type species, Mactra gigantea Lamarck, shows that the lack of well-developed cardinals is the result of the very large chondrophore, which has crowded the cardinals and caused them to approach obsolescence. They exist, however, as vestiges, in the left valve as two low, closely-appressed ridges, and in the right valve as a poorly developed, A-shaped tooth with the apex at the dorsal margin of the valve. In the type species, the umbones termi- nate at the actual dorsal margins of the valves, just above the apices of these minute cardinal teeth. S. catilliformis and S. hetnphilli have normal cardinal teeth, and only by enlarging the scope of Hemimactra beyond its differentiable characters could these Cali- fornia species be placed therein. Furthermore, these species are clearly much more closely related to Mactra polynyma. Mactra (Spisula) polynyma Stimpson Mactra similis Gray in Wood, Index Testae., Supplement, pi. 1, fig. .5, 1828; Beechey's Voy., Appendix, p. 154, pi. 44 fig. 8, 1828; not Say, 1822, fide Gould, 1841. Mactra grandis Deshayes, Ency. M^th., Vers, Vol. 2, p. 395, 1832; not Gmelin, 17SS, fide Gould, 1841. Mactra ovalis Gould, Silliman's Amer. Journ. Sci., N. S., Vol. 38, p. 196, 1840; Invert. Massachusetts, Ed. 1, p. 53, fig. 32, 1841; not Sowerby, 1817; Binney Edition, p. 75, fig. .32, 1870, figure reproduced by Dall, Bull. 37, U. S. Nat. Mus., pi. 70, 1SS9; not of Sowerby, 1817. Mactra ponderosa Philippi, Abbild. Beschreib. Conchyl., Bd. 1, Heft 7, p. 1, ]il. 1, fig. 1, October, 1844; not Conrad, 1830. Mactra polynyma Stimpson, Checklist East Coast Shells, Smithsonian Misc. Coll., Vol. 2, Art. 6, No. 3, p. 3, 1860, new name for M. ovalis Gould. M. (Spisnla) grayana Schrenck, 1867, fide Dall, 1894. Spisula (Mactromeris) polynyma Stimpson, Lamy, Journ. Conchyl., Ser. 4, Vol. 17, p]). 319-320, 1917. Distribution: Hudson's Bay south to Massachusetts and (?) Long Island, New York. This species is figured by Gould, Binney, Dall, and others, and need not be described here. It is a rather large shell. Although somewhat variable in shape, it is on the average more elongate than its Pacific coast variety. The figure given by Philippi, however (as M. ponderosa), shows a high-beaked form, and a study of more Atlantic and Pacific coast specimens may show the necessity of synonymizing the Pacific variety. Lamy has given a list of references to polynyma and its synonyms. 1 Treat. Malac, p. 369, 1S40, only species //. gigantea (Lamarck) and H. grandis Swainson; type designated by Gray, Proc. Zool. Soc. T.ondon for 1S47, p. 185, 1847, M . gigantea Lamarcic, Hist Anim. s. Vert., Vol. 5, p. 472, 1818. This is Mactra solidissima Chemnitz, Neues Syst. Conchyl. Cab., Vol. 10. p. 350. pi. 170, fig. 16.56, 1788; also figured by Reeve, Conch. Icon., Vol. 8, Mactra. pi. 11, fig. 8, 1854. This latter figure is an excellent illustration, showing the hinge as well as the exterior of a valve. Lamy also figures the type, op. cit. , figure on p. 292 (as Hemimactra solidissima (Chemnitz)). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 395 Mactra (Spisula) polyn5rma Stimpson variety voyi (Gabb) CalUsla voyi Gabb, Geol. Surv. Calif., Pala>o., Vol. 2, p. 24, pi. 5, fig. 41, 1866. "Mactra ovaMs Gould," Middendorff, Reise in dem Aussersten Norden und Osten Sibiriens wahrend 1843 und 1844, Bd. 2, Thl. 1, p. 363, 1851; not of Gould, Inv. Mass., Ed. 1, p. 53, 1841. Mactra polynyina variety alaskana Dall, Nautilus, Vol. 7, p. 128, April, 1894; Vol. S, p. 40, August, 1894. Spisula alaslensis Dall, U. S. Geol. Surv., Prof. Paper 59, p. 131, 1909. Mactra {Spisula) alaskana Dall, Baker, Nautilus, Vol. 24, p. 46, 1910. Spisula alaskana Dall, in Moffit, U. S. Geol. Surv., Bull. 533, p. 46, 1913; Dall, Journ. Wash. Acad. Sci., Vol. 19, p. 2, 1919. Spisula voyi (Gabb), Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 254, 1916; Packard, Vol. 9, p. 283, pi. 13, fig. 4, pi. 14, figs. 1, 2, pi. 15, figs, la, lb, 2, 1916; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922. Hemimactra {polynyma Stimpson, var.) alaskana Dall, U. S. Nat. Mus., Bull. 112, p. 51, 1921. Spisjda {Hemimactra) voyi Gabb, I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 59, pi. 38, figs. 1, 2, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 193, pi. 23, figs, 1, 2, 1924. Not "Spisula {Hemimactra) alaskana Dall," Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 59, pi. 4, fig. 4, 1924. Type locality: Near Humboldt Bay, below Bear River, Humboldt County; Pliocene. Pliocene: Various locaUties near Nome, Alaska (DaU, 1913); St. George Island, Pribilof group (Dall, 1919); near Humboldt Bay, at the type locality (Gabb); middle Wildcat formation of Humboldt County; Merced of Sargent oil field (Martin); Merced formation of Wilson's Ranch, Sonoma County (Dickerson). Recent: Arctic Ocean at Cape Lisburne, south to Bering Sea and the Aleutians and eastward to Puget Sound (Dall, 1921) ; north Japan, the Kurile Islands and the Okhotsk Sea (Schrenck). The variety voyi (Gabb) appears on the average to be less elongate than the typical form of the species, although Gabb's type figure appears to represent an elongate valve of the Pacific form, and Philippi's figure depicts a high form of the eastern shell. The sUght differences between the hinges of Atlantic and Pacific specimens seem to be indi- vidual variations, but we have had insufficient Atlantic specimens to be certain. It ap- pears quite certain that variety alaskana Dall and voyi (Gabb) are identical, and that the Pacific Pliocene to Recent shell is at most a variety of polynyma Stimpson. Mactra (Spisula) brevirostrata (Packard) Spisula brevirostrata Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 296, pi. 28, figs, la, 16, 2, 1916. Type specimen: In the University of California Collection. Type locality: One mile north of Scotia, Humboldt County; Pliocene. Pliocene: Wildcat formation, Pliocene of Humboldt County (Packard). This form appears to be intermediate in characters between albaria and voyi, forms which occur abundantly in the Wildcat beds and seem to intergrade there. It may be a synonym of either. Mactra (SpisulaJ albaria Conrad Plate 23, Figures 3n, 36 Mactra albaria Conrad, Amer. Journ. Sci., Ser. 2, Vol. 5, p. 432, fig. 4, 1848, reprinted by Dall, U. S. Geol. Surv., Prof. Paper 59, p. 150, fig. 4, 1909; Amer. Journ. Conch., Vol. 1, p. 152, 1865; Meek, Checklist Miocene Foss. N. A., p. 11, 1864; Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896; ? Arnold, U. S. Geol. Surv., Bull. 396, p. 30, pi. 19, fig. 4, Jan. 15, 1910; ? Bull. 398, pi. 41, same figure, 1910; J. P. Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 167, 172, 1912, Mactra diegoana Conrad, U. S. House of Repre,sentatives, Document No. 129, p. 14, 18.55; U. S. Pacific R. R. Repts., Vol. 5, p. 325, pi. 5, fig. 45, 1855; reprinted by Dall, 1909. "Standella planulata Conrad, sp.", Gabb, Geol. Surv. Calif., Palffio., Vol. 2, p. 91, 1868-9; not of Conrad, 1837. Spisula {Hemimactra) albaria Conrad, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 130, pi. 10, fig. 1, 1909. Spisula {Hemimactra) precursor Dall, U. S. Geol. Surv., Prof. Paper 59, p. 131, pi. 14, fig. 10, 1909. 396 San Diego Society of Natural History [Memoirs "Maclra gibbsana Meek," Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 187, pi. 2, figs. 19o, 196, 1909, fide Dall, 1922. ? "Tivela crassalelloides Conrad," Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 208, pi. 4, figs. 37a-c, 1909; not of Conrad. Spisula albaria Conrad, Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 576, 583, 588, 590, 594, 596 (cf.), 1913; Clark, Univ. Calif. Publ. GeoL, Vol. 8, p. 420, pi. 60, fig. 8, 1915; Nomland, Vol. 9, p. 203, 1916; Martin, Vol. 9, p. 254, 1916; Weaver, Proc. Calif. Acad. Sci., Ser. 4, Vol. 6, p. 37, 1916; Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 290, pi. 24, fig. 1, pi. 25, figs. 3-8, 1916; Nomland, Vol. 10, p. 220, 1917; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922; Clark, Univ. Calif. Publ. Geol., Vol. 15, p. 99, 1924. Spisula albaria Con. var. coosensis Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 99, pi. 9, figs. 6, 7, 1922. Maclra {Spisula) amoldi Dall, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 310, 1922. Type locality: On the Columbia River, near Astoria, Oregon; Miocene. Oligocene: Sooke formation of the southern coast of Vancouver Island; Newport, Oregon; Astoria, Oregon; Seattle horizon of Astoria series (Arnold and Hannibal; etc.). Miocene: Near Astoria, Oregon (Conrad; Clark, 1924) ; Nushagak, Alaska (Dall, 1896) ; Monterey formation, ClaUam Bay district, Washington, and at Astoria, Oregon (Arnold and Hannibal); Empire forma- tion of Oregon (Dall, 1909, as "iS. precursor;" Arnold and Hannibal); San Pablo and Santa Mar- garita formations of middle California (Clark, 1915; etc.). Pliocene: Middle Wildcat formation, Humboldt County (Martin) ; Merced and Purisima formations south of San Francisco; Sonoma County (Dickerson); Etchegoin of Sargent oil field, Pajaro VaUey (Martin; Nomland; etc.); Etchegoin of Coalinga district (Arnold, 1910; Nomland), includmg the JacaUtos formation (Clark, 1915); etc. This species has been figured and discussed by Packard, who recognizes a certain amount of variation, but gives the range of the species as upper Miocene (San Pablo) to Phocene ("Merced group")- The older records may have to be referred to varieties of the typical form. The original figure of Conrad is inadequate for specific difi'erentiation ; but Howe collected specimens at the type locality, and on the basis of small differences in the cardinal teeth of topotypes and of the albaria of Dall, Packard, and others, de- scribed a new variety. This variety we have tentatively placed in synonymy. Much more critical work will have to be done on this group before albaria and its possible var- ieties are well known. Mactra (Spisula) falcata Gould Maclra falcala Gould, Proc. Bost. Soc. Nat. Hist., Vol. 3, p. 216, 1850; U. S. Exploring Exped. (Wilkes), Vol. 12, p. 393, 1852, Mollusca Atlas, pi. 34, figs. 506, 506a, 506b, 1856, description reprinted in Gould's Otia Conchologica, p. 76, Boston, 1862. Standella falcata Gould, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 640, 1864, reprinted in Smithsonian Misc. Coll. No. 252, p. 126 (bottom pagination), 1872; ? Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 92, 1868-9; ? Cooper, 7th Ann. Rept. State Mineralogist, p. 266, in part only, 1888; Keep, West Coast Shells, p. 198, 1888; 1892; West American Shells, p. 97, in part, 1904. Spisula falcala Gould, Keep, West American Shells, Ed. 1, p. 97, in part, 1904; Ed. 2, p. 107, in part, 1911; ? Clark, Univ. CaUf. Publ. Geol., Vok 8, p. 420, 1915, questionably identified; Martin, Vol. 9, p. 254, 1916; Oldroyd, Univ. Wash., Publ. Puget Sound Biol. Sta., Vol. 4, p. 60, pi. 17, figs. 1-3 (reproductions of Gould's original figures), 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 195, pi. 20, figs. 1-3 (same figures), 1924. "Spisula planulala Conrad," Packard, Univ. Calif. Publ. Geol, Vol. 9, p. 293, pi. 16, figs. 3o, 3b, 3c, 1916. Spisula {Hemimactra) falcata Gould, Dall, Bull. 112, U. S. Nat. Mus., p. 52, in part, 1921. "Spisula {Heniimactra) alaskana Dall," Oldroyd, Univ. Wash., Publ. Puget Sound Biol. Sta., Vol. 4, p. 59, pi. 4, fig. 4, 1924. Type locality: Puget Sound, Washington; Recent. ? f Miocene: Reported from various locahties in the upper Miocene, — Ivirker's Pass, Contra Costa Co. (Gabb), San Pablo, questionably identified (Clark), etc. — ; but these occurrences must be considered ex- tremely doubtful until the identifications are confirmed by an examination of specimens. f Pliocene: Wildcat beds of northern California, Humboldt Co. (Cooper) ; Merced of Seven Mile Beach, middle California (Cooper); Merced of the Sargent oil field (INIartin); — occurrences more probable than those of the Miocene but should be verified. Recent: Queen Charlotte Islands and Puget Sound, possibly as far south as Cape Mendocino, but more southerly reports probably erroneous. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 397 Mactra falcata is very similar to M. polynyma variety voyi, to M. planulata, and to M. dolabriformis. It has been confused with voyi and planulata by Arnold, Dall, Packard, Oldroyd, and others, and all the reports of occurrences in the literature must be verified. M. dolabriformis is very much hke falcata in shape and hinge characters except that it has a well-defined ridge on the dorsal rim of the chondrophore separating the resilium from the ligament, and is therefore classed tentatively in the subgenus Mactra, s. s. There are also minor differences. The differences separating falcata from voyi and planulata, on the other hand, are all very slight, so slight that there can be little question about their relationship. They might even be considered varieties of a single species, or at least verj- young species that have just recently split off from a common stock. The fossil specimens may converge so that it will be found impossible to trace the slight differences back into the fossil record. It is absurd to separate /a^cato from polynyma, as Dall did in naming the section Symmorphomactra. Mactra falcata is well figured by Gould in the Mollusca Atlas to the U. S. Exploring Expedition Reports, and Gould's figures are twice reproduced by Oldroyd. It is smaller than voyi but is about the same shape as the young of that species, which are more produced anteriorly than the adults. The hinge is distinguished from that of voyi by the presence of accessory lamellae prolonging the anterior lateral teeth in the direction of the beaks, the one in the right valve nearly joining onto the anterior arm of the cardinal, the one in the left passing behind the cardinal. Like voyi, falcata is characteristically northern in its distribution. Mactra planulata, on the other hand, is characteristically southern in its distribution. It is usually a little more equilateral in shape, has a thicker shell, which is marked intern- nally by irregularities radiating from under the beaks ; and the liinge can be distinguished by the separating of the shorter anterior laterals from the accessory lamellae, the anterior arm of the right cardinal with the lamella attached being more oblique and distant from the laterals. Mactra (Spisula) planulata Conrad Mactra planulata Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, p. 240, 1837. ? Standella planulata Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 640, 1864, reprinted in Smithsonian Misc. Coll., No. 252, p. 126 (bottom pagination), 1872; not of Gabb, Geol. Suiv. Calif., Palseo., Vol. 2, p. 91, 1868-9, fossil records = albaria Conrad ( fide Packard) ; nor of Cooper, Stearns, etc. ( fide Packard) ; not of Keep, West Coast SheUs, p. 188, fig. 161, 1888, 1892. Spisula (Maclromeris) planulata Conrad, Amer. Journ.Conch., Vol. 3, Appendix, p. 45, 1868. Mactra planulata "var. falcata Gould," Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 187, 1892. Spisula {Hemimactra) planulata Conrad, Dall, Nautilus, Vol. 8, p. 40, 1894. "Spisula {Symmorphomactra) falcata Gould," Dall, Nautilus, Vol. 8, p. 41, in part, 1894; Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 297, pi. 26, figs, la, 16, Ic, 1916; Strong, Nautilus, Vol. 38, p. 102, 1925. "Mactra (Spisula) falcata Gould," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 176, pi. 19, fig. 1, 1903. Spisula {Symmorphomactra) planulata Conrad, Dall, Bull. 112, U. S. Nat. Mus., p. 52, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 195, 1924. Not "Spisula {Symmorphomactra) planulata Conrad," Oldroyd, Univ. Wash., Publ. Puget Sound Biol. Sta., Vol. 4, p. 60 (= falcata), pi. 17, figs. 4-6 (which are reproductions of Packard's illustrations of Mactra calif arnica) , 1924. Spisula planulata Conrad, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type locality: Near Santa Barbara; Recent. ?? Miocene: Possibly some of the reports oi falcata, etc., by Gabb, Cooper, etc. ? Pliocene: Possibly some of the reports of falcata by Cooper, Martin, etc. 398 San Diego Society of Natural History [ Memoirs Pleistocene: Lower San Pedro series at San Pedro and Dcadman Island, also Los Cerritos (= Signal Hill), Los Angeles Co. (Arnold) ; upper San Pedro series of the San Pedro region (Arnold) ; upper San Pedro series of Spanish Bight, San Diego (Arnold) ; upper Pleistocene of San Quintin Bay, Lower Cali- fornia (Jordan). Recent: Monterey, California, to Cape San Lucas, Lower California (Dall, 1921). For a comparison with this species, see the notes on M. falcata. Mactra (Spisula) hemphilli Dall Mactra hemphilli Dall, Nautilus, Vol. 7, p. 137, pi. 5, fig. 2, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 175, pi. 19, fig. 3, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 526, 1907. Spisula (Hemimaclra) hemphilli Dall, Nautilus, Vol. 8, p. 40, 1894; U. S. Nat. Mus., Bull. 112, p. 52, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 194, pis. 46, 50, 1924; Strong, Nautilus, Vol. 38, p. 101, 1925. Spisula hemphilli Dall, Keep, West Amer. Shells, p. 106, 1911; Martin, Univ. Calif. Publ. tieol.. Vol. 9, p. 254, 1916; Packard, Vol. 9, p. 287, pis. 21, 22, 1916; Nomland, Vol. 10, p. 220, 1917; not of Reagan, 1909,^de Dall, 1922. Spisula cameronis Dall, West .American Scientist, Vol. 19, No. 3, p. 22, 1921; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 26, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Type specimens: In the U. S. National Museum. Type localities: Of hemphilli, San Diego, Cahfornia; Recent; of cameronis, San Quin- tin Bay, Lower Cahfornia, Mexico; Pleistocene. Pliocene: Chione elsmerensis zone, lower part of the Etchegoin formation, lower Pliocene of the Coalinga region (Nomland); Purisima and Merced formations south of San Francisco (Martin); lower Fernando of Elsmere Canyon, Los Angeles County (questionably identified, Arnold, 1907). Pleistocene: Rare in upper San Pedro series at San Pedro; common at the foot of Twenty-sixth Street, San Diego (Arnold, 1903); Newport, Los Angeles County (Packard, 1916); upper Pleistocene at San Quintin Bay, Lower California, Mexico, as cameronis (Dall, 1921, as Pliocene or Pleistocene; Jordan, as upper Pleistocene). Recent: San Pedro, California, to Todos Santos Bay, Lower California, Mexico (Jordan). This large Mactra differs from catilliformis in the long anterior portion of the shell, which is concave in profile along the dorsal margin. The hinge is of the same type as that of catiUifor7ms but the laterals are a little longer. Also, the pallial sinus of hemphilli is more inclined upward. M. hemphilli is closely related to catilliformis. According to Dall (Amer. Journ. Sci., Ser. 5, Vol. 4, p. 311, 1922) "Spisula hemphilli Dall" of Reagan (Trans. Kansas Acad. Sci., Vol. 22, p. 212, pi. 4, fig. 43, 1909) is an er- roneous identification based upon a shell which Dall names "Mulinia olympica." Reagan reported his "hemphilli" abundant "in the Quillayute formation at the old mouth of Maxfield Creek." This is probably reworked Empire formation sandstone. Spisula cameronis Dall was based upon a single specimen of a shell which appears to be a half-grown hemphilli, according to Dall's description and figure. Mactra (Spisula) catilliformis (Conrad) Plate 23, Figures 4, 10 Spissula catilliformis Conrad, Amer. Journ. Conch., Vol. 3, p. 193, 1867. "Standella californica Conrad," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 640, 1864; not of Conrad, 1837, nor of Deshayes, 1852. Mactra catilliformis Conrad, DaU, Nautilus, Vol. 7, p. 137, pi. 5, fig. 3, 1894; J. P. Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 172, 1912. Spisula {Hemimactra) catilliformis Conrad, Dall, Nautilus, Vol. 8, p. 40, 1894; U. S. Nat. Mus., Bull. 112, p. 52, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 194, pi. 24, 1924; Strong, Nautdus, Vol. 38, 1925. Mactra (Spisula) catilliformis Conrad, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 176, pi. 19, fig. 5, 1903. Spisula catilliformis Conrad, var. alcatrazensis Arnold, Smithsonian Misc. Coll., Vol. 50, p. 19, pi. 56, fig. 6, 1907. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 399 Spisiila adilliformis Conrad, Keep, West Aiiier. Shells, \i. ICO, fig. S3, 1911; English, Univ. Calif. Piibl. Geo!., Vol. 8, p. 210, 1914; Clark, Vol. 8, p. 420, pi. 59, fig. 1, 1915; Martin, Vol. 9, p. 254, 1916; Packard, Vol. 9, p. 285, pis. 17, 18, 19, 1916; Univ. Calif. Publ. Zool., Vol. 14, p. 282, pi. 24, fig. 2, pi. 27, figs. 1, 2, 1918; Oldroyd, Univ. Wash., Publ. Puget Sound Biol. Sta., Vol. 4, p. 59, pi. 39, fig. 1, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. ? Spisula mercedensis Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 286, pi. 20, 1916. Type locality: "Panama," according to Conrad; Recent. Miocene: Temblor formation, middle Miocene of California (J. P. Smith); lower Neocene; upper and lower San Pablo and Santa Margarita formations, upper Miocene of middle California (Clark); ? Santa Margarita formation north of Coalinga (Nomland, questionably identified). Pliocene: Lower Fernando of Holser Canyon, Los Angeles County (English); Etchegoin formation of middle California (Clark) ; rather common in the Cryplomya calif ornica zone, lower Etchegoin, of well cores in the southern end of the San Joaquin basin near Bakersfield and near Tipton, also found higher in the section (H. R. Gale); middle part of Wildcat formation, Humboldt County; Purisima and Merced formations of San Francisco region (Martin); Pacific Beach, San Diego (Arnold, 1903). Pleistocene: Barlow's Ranch, near Ventura; upper San Pedro series at San Pedro, Los Cerritos, Crawfish George's, and Deadman Island, "rather common;" Pleistocene of Pacific Beach, Spanish Bight, and San Diego (Arnold, 1903); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Neah Bay to San Diego, California (Dall, 1921 ) ; Panama range denied by Dall. This is a large, thin shell with nioderatelj' anterior beaks and a deep pallial sinus. Individuals attain a length of 130 mm., but the average specimen measures about 110 mm. in length and 85 mm. in height. Mactra hemphilli Dall has also a large shell, but the anterior portion of the valves protrudes much farther than do those of catilliformis and the anterior dorsal margin is concave. The hinges are similar, but catilliformis has shorter laterals. Mactra (Spisula) mercedensis Packard is an unusual variant of catilliformis. It occurs at its type locality near Mussel Rock (lower part of the Merced formation), at the south end of Seven Mile Beach, San Mateo County, with normal forms of catilliforynis, and also in the Etchegoin formation of well cores from the southern part of the San Joaquin basin near Tipton, Formosa, and Bakersfield. If it is to be separated as a variety, the distin- guishing character will be the unusually anterior beaks; but its association with the typical form suggests that it is but an unusual individual variation. Similar variations in the position of the beaks occur in other species, for example M. pohjnyma, var. voyi. Mactra (? Spisula) sisquocensis (Arnold) Spisula sisquocensis Arnold, Smithsonian Misc. Coll., Vol. 50, p. 437 (Pt. 4, p. 19), pi. .56, fig. 1, 1907; Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 302, 1916. Type specimen: In the U. S. National Museum, Catalogue No. 165,292. Type locality: Alcatraz Asphalt mine, near Sisquoc, Santa Barbara County. Pliocene: "Fernando formation, lower Pliocene portion," at the type locality (Arnold). According to Arnold, "This species is near S. hemphilli Dall, but is constantly and decidedly narrower." The hinge is as yet unknown. Mactra (? Spisula) coalingensis Arnold Mactra coalingensis Arnold, U. S. Geol. Surv., Bull. 396, p. 71, pi. 25, fig. 4, Jan. 15, 1910; Bull. 398, pi. 47, same figure, 1910. Spisula coalingensis Arnold, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 254, 1916; Packard, Vol. 9, p. 301, pi. 27, fig. 8, 1916; Nomland, Vol. 10, p. 220, 1917. 400 San Diego Society of Natural History [Memoirs Type specimen: In the U. S. National Museum, Catalogue No. 165,513. Type locality: Glycymeris bed on north side of Alcalde Canyon, two miles northeast of Alcalde, Coalinga district; Pliocene. Pliocene: Etchegoin formation of Coalinga district (Arnold); Merced of Sargent oil field (Martin); upper Sargent (Nomland). This species was compared to falcata, but the hinge has not been seen. It is said to be less ventricose than albaria. A number of Mactras have been described from the earlier Tertiary formations of California, but as they have been discussed and figured by Packard or by later authors they need not be mentioned here. "Spisula" longa Dall, from the Pleistocene of Lower California, Mexico, is a Schizothoerus and will be discussed under that genus. Subgenus MULINIA Gray, 1837 Mulinia Gray, Proc. Zool. Soc. London for 1836, p. 104, February, 1837, nomen nudum; Loudon's Mag. Nat. Hist., New Series, Vol. 1, p. 375, July, 1837; Dall, Nautilus, Vol. 8, p. 27, 1894; Proc. Malac. Soc. London, Vol. I, p. 211, 1895. Type (by original designation), Mulinia typica Gray, = Mactra edulis King and Broderip, Zool. Journ., Vol. 5, p. 335, July, 1832; Patagonia and Straits of Magellan. Shape like that of Mactra, s. s., but with the ligament entirely internal and not sep- arated from the chondrophore by a shelly ridge. There has been some misunderstanding of the true characters of Mulinia Gray, probably because of unfamiliarity with Gray's original description in Loudon's Magazine of Natural History. In 1856 Conrad described a very heavy and ventricose Mactroid shell under the name of Mulinia densata. Later Gabb stated that Conrad had confused two species, and went on to apply Mulinia densata to a form which he described as possess- ing a thin shell and slender teeth. What he figured can hardly be Conrad's species. Other authors have used the name, Mulinia densata Conrad, for Conrad's original heavy-shelled species, which Gabb appears to have renamed Schizodesma abscissa. This confusion is pointed out here, as it illustrates the introduction of the very improper use of Mulinia for the grotesque, heavy, Mactroid shells that should be classified under Pseudocardium Gabb. Mulinia was described by Gray as follows : "Shell ovate, trigonal, subangular at each end. Cardinal and lateral teeth like Mactra. Siphonal inflection ovate, distinct. Ligament internal ! in a triangular groove in the upper surface of the deep cartOage pit, quite hid from view." Mactra (Mulinia) pallida Broderip and Sowerby Plate 22, Figures 7a, 76, 7c Mactra pallida Broderip and Sowerby, Zool. Journ., Vol. 4, p. 360, 1829; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 175, 304, 1857. Mulinia donaciformis Gray, Loudon's Mag. Nat. Hist., New Series, Vol. 1, p. 376, July, 1837; Sowerby, Zool. Beechey's Voy., Moll., p. 154, pi. 44, fig. 13, 1839; ? C. B. Adams, Ann. Lyceum Nat. Hist., New York, Vol. 5, p. 517, 1852; Conrad, Amer. Journ. Conch., Vol. 3, Appendi.x, p. 31, 1868. Mactra carinulata Deshayes, ia Reeve, Conch. Icon., Vol. 8, Mactra, pi. 10, fig. 38, April, 1854; Deshayes, Proc. Zool. Soc. London for 1854, p. 67, February 10, 1855, young specimen ?. Mactra goniata Gray, MS., Deshayes, Proc. Zool. Soc. London for 1854, p. 70, February 10, 1855; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 287, 304, 1857. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OP CALIFORNIA 401 Macira angulata Gray, MS., Reeve, Conch. Icon., Vol. 8, Maclra, pi. 9, fig. 34, April, 18.54; Lamy, Bull. Mus. BUst. Nat. Paris, Vol. 14, p. 51, 1908. Macira donacdformis Gray, Reeve, Conch. Icon., Vol. 8, Maclra, sp. 62, pi. 13, fig. 60, not figure 62, April, 1854. Maclra (Mulinia) angulala Gray, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., pp. 52, 549, 1855-57; Brit. Assn. Adv. Sci., Rept. for 1856, p. 246, 1857. Mulinia angulala Gray, H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 380, 18.56. Mulinia carinulata Deshayes, H. and A. Adams, op. cil., p. 380, 1856. Mulinea angulata Gray, Conrad, Amer. Journ. Conch., Vol. 3, Appendix, p. 31, 1868. Midinea carinulata Deshayes, Conrad, op. cil., p. 31, 1868. Mulinea donaciformis Gray, Conrad, op. cil., p. 31, 1868. Mulinia pallida Broderip and Sowerby, Dall, Nautilus, Vol. 8, p. 41, 1894; Proc. U. S. Nat. Mus., Vol. 37, p. 274, 1909. Shell of moderate size, ventricose, the anterior end short, broadly rounded, the posterior pro- duced and acutely rounded at the ventral end, flattened considerably in a broad posterior area from the end of the umbo to the posterior ventral point of the valve, producing an angulation similar to that on Macirella; sculpture absent except for growth lines; hmge normal, chondrophore deep; paUial smus rather small. Measurements: Length, 60 mm.; height, 43 mm.; convexity of one valve, 17 mm. (large specimen from Panama). Type locality: San Bias, Tepic, Mexico; Recent. Broderip and Sowerby described Mactra pallida from Recent specimens collected at San Bias, west coast of Mexico. In 1837 Gray briefly described Mulinia donaciformis, which he stated came from the "South Seas." This species was figured by Sowerby in the Zoology part of the report on Beechey's Voyage and was said to have come from the Isle of Nevis in the Antilles, where Beechey did not land. Reeve (1854) figured donaciformis, but attributed it to New Zealand, which is certainly an error. C. B. Adams (1852) questionably identified some Panama shells with donaciformis, basing his identification on the small figures in Hanley's supplement to Wood's Index Testaceologicus. Comparison of a small series of Donaciform Mulinias from the southern fauna with plates of the "species" included in the above synonymy (where figured) indicates that the name pallida should be used for the somewhat variable but characteristically ventricose, high beaked, posteriorly pointed shells which range from the Gulf of California to Ecua- dor. In \'iew of the amount of variation shown in the collections, it may be necessary to include several other supposed species in the synonymy of pallida. Mactra (Mulinia) pallida Broderip and Sowerby variety modesta (Dall) Mulinia modesta Dall, Nautilus, Vol. 8, p. 5, pi. 1, lower figure. May, 1894; p. 41, Aug., 1894. Mulinia coloradoensis Dall, op. cit., p. 6, pi. 1, upper figure; May, 1894; p. 41, Aug., 1894. Mulinia coloradoensis, var. actda Dall, op. cit., p. 6, pi. 1, left figure. May, 1894; p. 41, Aug., 1894. "Mactra exoleta Gray," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 175, pi. 19, fig. 4, 1903; not Mactra exoleta Gray, Loudon's Mag. Nat. Hist., New Series, Vol. 1, p. 372, 1837. "Mactra {Macirella) exoleta Gray," Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 281, pi. 12, figs. 4a, 46, pi. 13, fig. 2, 1916; not of Gray. Shell small or of moderate size, ovate-triangular, and similar to pallida, but generally not so' acutely pointed at the posterior ventral end and generally with broader, less promment umbones, and less abrupt flattening of the posterior portion of the valves. Size: Length, 42 mm.; height, 31 mm.; convexity of both valves together, 24 mm. Type specimens: In the U. S. National Museum. Type localities: Of modesta, Guaymas, Mexico, Recent; of coloradoensis, estuary of the Colorado River, head of the Gulf of California, Mexico, Recent; of variety acuta, same as coloradoensis. Pleistocene: Lower Pleistocene at Signal HiU (T. S. Oldroyd collection) ; upper San Pedro series of San Pedro, "rare" (Arnold); Newport, Los Angeles County (Packard); Spanish Bight and Pacific Beach, San Diego (Arnold); lower Quaternary, Magdalena Bay, Lower CaUfornia, Mexico (E. K. Jordan). Recent: Lower California and the GuK of Cahfornia, Mexico. 402 San Diego Society of Natural History [Memoirs Arnold's figured specimen of "Mactra exoleta Gray" is in the geological museum at Stanford University. It belongs to the subgenus Mulinia and is very close to M. pallida, though it appears to be less pointed posteriorly. There are three specimens of the same form in the T. S. Oldroyd collection of Pleistocene fossils from Signal Hill ( = "Los Cer- ritos" of Arnold), Los Angeles County. Packard discusses Mactra exoleta Gray, carefully describing the "well-developed shelly ridge" separating the ligament from the chondro- phore; but he figures a specimen that is clearly a Mulinia, with a hinge very different from that of Mactra exoleta. There is little doubt that the shell figured by Packard rep- resents the same form as the shell figured by Arnold. Both have a remote external re- semblance to Mactra exoleta, but a comparison of specimens shows that the latter species is entirely different. The true Mactra exoleta has an exceptionally prominent shelly partition separating the chondrophore from the external ligament, whereas the present species has an entirely internal ligament attached to the upper wall of the chondrophore. Also, the posterior dorsal margin of M. exoleta descends abruptly, making almost a right angle with the anterior drosal margin, and causing the posterior lateral teeth to be rela- tively very much shorter. M. exoleta attains a much larger size than does pallida; a large specimen in the Stanford collection from the coast of Guerero, Mexico, has a length of 118 mm., a height of 85 mm., and a convexity (one valve) of about 30 mm. The ligament diverges anteriorly from the valve margin in a narrow slit extending to a point beneath the umbo. It belongs to the group Mactrella Gray.' Although Mactrella exoleta has not yet been reported fossil in California, a specimen is shown on plate 22, figures 10a, 106, for comparison. Mactra modesta (Dall), M. coloradoensis (Dall), and its variety acuta (Dall) are probably variations within a single variety of pallida. The amount of variation exhibited by pallida suggests that all three of these forms named by Dall are very closely related and are hardly worthy of separate names. Dall's figures, especially of modesta and of coloradoensis, are so similar to the Mulinia figured by Arnold, to the figures of exoleta given by Packard, and to the specimens collected by Mr. Oldroyd that they are all here identified as the variety modesta of pallida. Subgenus PSEUDOCARDroM Gabb, 1866 Pseudocarditmi Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, pp. 20, 21, 1866. Type (by monotypy), Pseudocardium gabbii (Remond), = Mulinia densato Conrad ; Miocene and Pliocene of California. Shell thick, heavy, ventricose, quite variable in shape, generally high, with strongly curved umbones; sculpture of irregular, course growth lamellse; hinge Mactroid, heavy, with a deep chon- drophore, ligament external, extending into chondrophoric cavity and often produced in a slit that descends from the valve margin to a point below the umbo; laterals well developed, often very large; pallial sinus rather short, rounded at end. Geologic range : Ohgocene (or upper Eocene) to middle Pliocene. Gabb introduced the genus Pseudocardium for the heavy-shelled, ventricose Mac- troid species which Remond had described as "Cardium gabbii" but which had previously been named "Mulinia" densata by Conrad. Gabb recognized the characters of Mulinia Gray, but misconstrued Conrad's species densata, applying that name to some thin- shelled species. Although Conrad's description of "Mulinia" densata is short and his > Ann. Mag. Nat. Hist., Ser. 2, Vol. 11, p. 42, January, 1S53. monotype, M. striatula Linnffius. Syst. Nat., Ed. 12, p. 1125, 1767 (? =M. alata Spengler, + M. carinata Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 473, 181S); H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 377, 1856. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 403 figure none too good, it is apparent that he could not have had any thin-shelled species with slender teeth, for he described his form as being "ventricose, thick," and as having the "lateral teeth very robust and prominent." Gabb may have been misled by the pe- culiar shape of Conrad's figure, but very inequilateral specimens of densata occur in any large collection. One is figured by Packard. Unfortunately, Gabb renamed the true densata as Schizodesma abscissa.^ Schizodesina Gray, or more properly Scissodesma,- is typically a trigonal shell with small, distant umbones, a very wide cardinal area, and a ligament in a triangular slit which opens below into the chondrophore and extends upward away from the valve margin at a large angle, the sharp point ending under the apex of the umbo. Scissodesma has little in common with Pseudocardium other than characters which are due to its membership in the Mactroid group. The ligament slit continuing almost to the umbo is a feature exhibited by a number of species of Mactra which are not closely re- lated according to their other characters, and the deep chondrophore of Pseudocardium is a function of the ventricosity and the thickness of its shell. The powerful lateral teeth of Pseudocardium are likewise the result of the heavy shell, which requires a correspondingly rigid mechanical construction of the hinge, and are not like the stout lateral teeth of Scissodesma, which are thick to make up for their shortness. With sufficient material it may be possible to show that Pseudocardium represents a Mactra, s. s., or a SpisuJa, perhaps M. albaria, that has been distorted by peculiar ecologic conditions. The extreme abundance of the type species concentrated in beds practically by itself is suggestive of brackish water conditions. Mactra (Pseudocardium) densata (Conrad) Mulinia densata Conrad, Proc. Acad. Nat. Sci. Phila. for 18.56, p. 313, 1856; U. S. Pac. R. R. Repts., Vol. 6, p. 71, \A. 3, fig. 12, 1857; Cooper, 7th Ann. Rept. Calif. State Mineralogi-st, p. 252, 1888; Arnold, U. S. Geol. Surv., Bull. 396, pp. 140, 148, pi. 17, fig.s. 3, 4, pi. 21, fig. 3, Jan. 15, 1910; Bull. 398, pi. 39, figs. 3, 4, pi. 43, fig. 3, 1910; Arnold and Hannibal, Proc. Amer. Pliilos. Soc, Vol. 52, pp 590, 593, 594, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 418, 1915; Packard, Vol. 9, pp. 304, 305, pis. 29-33, 1916; Nomland, Vol. 10, p. 219, 1917; Howe, Vol. 14, p. 92, 1922; Hoots, Bull. 812-D, U. S. Geol. Surv., p. 278, 1930; not "? M. densala Conrad" of Gabb, 1866. Cardiiim gabbii Remond, Proc. Calif. Acad. Sci., Vol. 3, p. 13, 1863. Schizodesma abscissa Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 20, pi. 4, figs. 34, 34«, 1866; Hoots, Bull. 812-D, U. S. Geol. Surv., p. 284, 19.30. Pseudocardium gabbii Remond, Gabb, op. cit., p. 21, pi. 6, figs. 47, 47o, 476, 47f, 47J, 1866. Mulinia oregonensis Dall, U. S. Geol. Surv., Prof. Paper 59, p. 132, ])1. 9, figs. 2, 3, pi. 13, fig. 5, 1909. f Mulinia densata Conrad, var. rtiinor Arnold, U. S. Geol. Surv., Bull. 396, p. 54, pi. 5, fig. 6, January 15, 1910; Bull. 398, pi. 27, same figure, 1910. Spisula abscissa (Gabb) Packard, Univ. Calif. Publ. Geol., Vol. 9, p. 289, pi. 23, fig. 4, pi, 24, fig. 2, 1916. Pseudocardium gabbi, Pack, Prof. Paper 116, U. S. Geol. Surv., p. 45, 1920. Type locality: Santa Barbara or shores of San Pablo Bay; Miocene. Miocene: ? Vaqueros formation, lower Miocene (Arnold, var. minor); Empire formation of Oregon (Arnold and Hannibal; Dall, as M. oregonensis); San Pablo formation of middle California (Clark); Santa Margarita formation, upper Miocene (Nomland). Pliocene: Coos conglomerate (Dall; Howe); Etchegoin formation (Arnold; Nomland); Etchegoin of the southeastern end of the San Joaquin basin (Pack, as gabbi; Hoots, as densata and abscissa); Merced and Purisima formations of middle California (Arnold and Hannibal; etc.). This species has been discussed above under the subgenus Pseudocardium. It has been well figured by Arnold and Packard and need not be described here. It is hoped that it will no longer be classed as a Mulinia. ' Gabb., op. cit., p. 20, pi. 4, figs. 34, 34a, 1866. 2 Gray, Loudon's Mag. Nat. Hist., New Series, Vol. 1, p. 370, 1837, S. spengleri included and figured; Proc. Zool. Soc. London lor 1847, p. 185. 1847, spelling changed to Schizodesma, S. spengleri designated as type. 404 San Diego Society of Natural History [Memoirs Packard considered Schizodesma abscissa a Spisula, but the present authors believe that it is but a variant of densata not entitled to a varietal name.' Genus SCHIZOTHAERUS Conrad, 1853 Crijptodon Conrad, Journ. Acad. Nat. Sei. Phila., Vol. 7, p. 235, 1837; not Cryptodon Turton, Conch. Insul. Brit., p. 121, 1822; nor Cryptodon Latreille, 1833. Tresus Gray, Ann. Mag. Nat. ffist., Ser. 2, Vol. 11, p. 44, January, 1853; Dall, Nautilus, Vol. 8, p. 42, 1894; Proc. Malac. Soc. London, Vol. 1, p. 212, 1895; Trans. Wagner Inst. Sci., Vol. 3, p. 885, 1898; Lamy, Journ. de Conchyl., Ser. 4, Vol. 17, p. 378, 1917; not Tresus Walekenser, Ann. Soc. Ent. France. Vol. 2, 1833, Arachnida. Schizothserus Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 6, p. 199, January, 1853. Type (by monotypy), Schizothoerus nuttallii (Conrad), 1837; shores of north Pacific Ocean, also fossil. Shell ovate, oblong, ventricose, hinder gape roundish; hinge with the cardinal teeth small, lateral teeth very small, close to the cardinals; ligament external, margmal, separated from the cartilage-pit by a shelly plate. (Gray's description of Tresus.) Schizothcerus is a small genus of Mactroid shells modified by the burrowing habit of the animal. There is only one known valid living species, with possibly a few varieties. It may have been derived from Mactra catilliformis or some similar species in the Miocene. Schizothaerus nuttallii (Conrad) Plate 22, Figure 9; Plate 23, Figures 8a, 86, 9 Lutraria {Cryplodon) nutlaUii Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 235, pi. 18, fig. 1, 1837. Cryptodon nuttallii Conrad, Gray, Proc. Zool. Soc. London for 1847, p. 185, 1847; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1856, pp. 194, 300, 349, 1857; Rept. for 1863, pp. 525, 586, 1864. Lutraria maxima Middendorff, Mem. Acad. Imp. Sci. St.-Petersbourg, Ser. 6, Vol. 6, p. 560, pi. 19, figs. 1-4, 1849; Reeve, Conch. Icon., Vol. 8, Lntraria, pi. 5, fig. 18, 1855; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 192, 209, 219, 224, 300, 1857; Rept. for 1863, p. 600, 1864. Lutraria capax Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 217, 1850; U. S. Expl. Exped. (Wilkes), Moll., p. 395, 1852, Atlas, pi. 34, fig. 508, 1856; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 209, 213, 1857; Rept. for 1863, p. 531, 1864. Tresus maximus Middendorff, Gray, Ann. Mag. Nat. Hist., Ser. 2, Vol. II, p. 42, 1853; H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 381, 1856; Chenu, Man. Conchyl., Vol. 2, p. 59, fig. 243, 1862; Conrad, Amer. Jomn. Conch., Vol. 3, Appendix, p. 46, 1868. Lutraria inflala Dunker, Zeitschr. f. Malak., Vol. 10, p. 112, 1853; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 296, 1857. Schizothserus nuttallii Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 6, p. 199, 1853; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 525, 586, 1864; Tryon, Struct. Syst. Conch., Vol. 3, p. 161, pi. 110, fig. 21, 1884; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 264, IS88, "Schizothoerus;" Thompson, Rept. B. C. Commissioner of Fisheries for 1912, pp. 1-39, 1-47, pi. 5, 1913; Clark, Univ. Calif. Publ. GeoL, Vol. 8, p. 420, 1915; Martin, Vol. 9, p. 254, I9I6; Packard, Vol. 9, pi. 35, I9I6; Nomland, Vol. 10, pp. 303, 304, 1917; Packard, Univ. CaUf. Publ. Zool., Vol. 14, p. 283, pi. 28, figs, la, lb, I9I8; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 54, pi. 16, fig. 3, 1920; Dall, U. S. Nat. Mus., BuU. 112, p. 52, 1921; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 564, 1922; Oldroyd, Univ. Wash., Publ. Puget Sound Biol. Sta., Vol. 4, p. 60, pi. 33, figs. lo, 16, 1924; Stanford Univ. Publ. GeoL, Vol. 1, p. 196, pi. 31, figs, la, 16, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925; E. K. Jordan, Proc. Cahf. Acad. Sci., Ser. 4, Vol. 15, p. 255, 1926; WaterfaU, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Mactramaxima Middendorff, Reeve, Conch. Icon., Vol. 8, Mactra, pi. I, fig. 4, 1854. Lutraria nuttallii Conrad, Lischke, Japanische Meeres-Conchyl., Vol. I, p. 136, 1869; Vol. 2, p. 123, 1871. Tresus nuttallii Conrad, Dunker, Index Moll. Maris Japonici, p. 184, 1882; Dall, Nautilus, Vol. 8, p. 42, 1894; Proc. Malac. Soc. London, Vol. 1, p. 212, 1895; Trans. Wagner Inst. Sci., Vol. 3, p. 885, 1898; Lamy, Journ. de Conchyl., Ser. 4, Vol. 17, pp. 379, 380, text figures, 1917. Schizothserus nuttallii capax Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 52, 1921; Oldroyd, Univ. Wash., Publ. Puget Sound Biol. Sta., p. 61, 1924; Stanford Univ. Publ. Geol., Vol. 1, p. 196, 1924. ' Stewart figures Gabb's type of abscissa (Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 210, pi. 16, fig. 6, 1930) and proposes for it the new name Stereomactra, which thus becomes a synonym of Pseudocardium. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 405 Spisulalonga Dall, West American Scientist, Vol. 19, p. 22, 1921; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 27, pi. 10, fig. 1, pi. 11, fig. 3, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 244, 1926. Schizothxrits cf. pajaroensis Conrad, Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922. "Macira nasuia Gould," of Pacific coast coOectors, probably not of Gould, 1851. Shell large, elongate-ovate, ventricose, with anterior l^eaks, posterior gajie broad; pallial sinus confluent at base with pallial line. Type localities: Of 7ndtallii, near Santa Barbara, Recent; of capax, Puget Sound, Recent; of longa, San Quintin Bay, Lower California, Mexico, Pleistocene. Miocene: Montesano ?, upper Miocene of western Washington (Howe) ; Empire formation of Coos Bay region, Oregon (Dall, 1909); lower San Pablo, upper Miocene of middle California (Clark); questionably at type section of Santa Margarita formation, Nacimiento River (Nomland, 1917) ; Santa Margarita, Miocene (Clark). Pliocene: Merced and Purisima formations in region south of San Francisco (Arnold and Hannibal; Martin); Wildcat formation of Humboldt County (Martin); Merced formation near Freestone, Sonoma County (Dickerson); Jacalitos and Etchegoin formations of Coalinga region (Clark); Chione elsmerensis and Turritella nova zones, lower part of the Pliocene near Coalinga (Nomland) ; Santa Barbara (Cooper); lower "Pico" near Ventura (Waterfall). Pleistocene: Santa Barbara to San Diego (Cooper) ; Los Cerritos (Arnold) ; rare in lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd); Tomales Bay, Marin County (Dickerson); upper Pleisto- cene at Campbell Ranch, southwest of Goleta, Santa Barbara County, S. D. S. N. H. localities 40 and 74 (F. X. Johnston, U. S. Grant, collectors); upper San Pedro series at San Pedro, Crawfish George's, and San Pedro; also at Spanish Bight, San Diego (Arnold); "Saugus," near Ventura (Waterfall) ; Pleistocene of San Quintin Bay (as "Sjnsula longa" Dall, 1919; as Schizothxrus nutlallii Conrad, Jordan). Recent: Cordova, Prince William Sound, Alaska (McMillin); south to Soammons Lagoon, Lower California, Mexico (Jordan); also, northern Japan (Lischke; Dunker; etc.). This species is easily recognized by its large size, ventricosity, rounded posterior gape, strong chondrophore, and very small, short lateral teeth. Lutraria maxima and L. capax are unquestionable synonyms. Dall sought to use capax for the very short, high, subglobose variants, but Gould's type figure is of a typical nuttallii. The original descrip- tion of Lutraria inflata has not been consulted, but it refers to a living California Schizo- thcerus of which there is but one species. "Spisula" longa Dall is a young nuttallii, ac- cording to Dall's figures. Mactra nasuta Gould (Proc. Boston Soc. Nat. Hist., Vol. 4, p. 88, 1851), which was stated to inhabit Mazatlan, Mexico, and San Pedro, California, may be a rare species which is now not definitely known. The shells in CaUfornia collections which are labeled M. nasuta generally prove to be the young of Schizothcerus nuttallii. Schizothaenis nuttallii (Conrad) variety pajaroanus (Conrad) Plate 22, Figures 60,, 6b, 8 Venus pajaroana Conrad, U. S. Pacific R. R. Repts., Vol. 7, Pt. 1, p. 192, pi. 4, figs. 1, 2, 1857. Schizolhssrus pajaroanus Conrad, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 130, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 590, 593, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 420, 1915; Martin, Vol. 9, pp. 239, 243, 245, 254, 1916; Howe, Vol. 14, p. 92, 1922. Shell averaging smaller than that of tyjjical Schizothcerus nuttallii, less ventricose, with smaller, less rounded posterior gape, and with umbones often more anterior in position. Type specimen: In the U. S. National Museum, No. 13,318. Type locality: "Pajaro River, Santa Cruz" (Conrad). 406 San Diego Society of Natural History [Memoirs Miocene: Montesano, middle Miocene of Washington; Empire formation, Coos Bay, Oregon (Dall, 1909; Arnold and Hannibal; Howe); lower San Pablo of middle California (Clark, 1915). Pliocene: Coos Conglomerate of Coos Bay, Oregon, questionably (Howe); Purisima and Merced formations in region south of San Francisco (Arnold ; Martin) ; Etchegoin of Coalinga region ; Wildcat formation of Humboldt County (Martin). This variety is readily distinguished by its smaller size, less ventricose valves, and smaller, less rounded posterior gape. Conrad's figures suggest dementia pertenuis (Gabb), but his type specimen is a Schizothcerus. Genus ANATINA Schumacher, 1817 ? Anaiina Renier, 1804, nomen nudum. Not Anatine Lamarck, 1809 and 1812, vernacular use only, fide Iredale, Proc. Malac. Soe. London, ^'ol. 11, p. 304, 1915. Anaiina Schumacher, Ess. Nouv. Syst. Habit. Vers Test., pp. 125-126, 1817. Not Anaiina Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 462, 1818. Labiosa Schmidt, in MoUer, Isis (Oken), p. 130, 1832 (? Schmidt, Vers. Einth. Conch., 1828); Dall. Trans. Wagner Inst. Sci., Vol. 3, pp. 881, 882, 906, 1898; Lamy, Journ. de Conchyl., Ser. 4, Vol. 17, p. 348, 1917. Type (by monotypy), Anatina pellucida Schumacher, op. cit. p. 126, pi. 8, fig. 1, 1817, = Mactra anatina Spengler, Skrift. Naturh. Selsk., Vol. 5, Pt. 2, p. 120, 1802; figured by Gray, in Wood, Index. Test., Suppl., pi. 1, fig. 1, 1828, as Mactra cyprinus Gray; habitat, ? Pacific coast of Mexico. Shell small or medium m size, thm-shelled, ventricose, beaks adjacent, posterior gaping, laterally somewhat flattened, sub-rostrated; sculpture consisting of fine growth hues only or of gro^\i:h lines and concentric undulations ; hinge with prominent chondrophore ; cardinal teeth small but definitely formed, partly overhanging the chondrophore; anterior lateral obsolete, posterior small and short; hmge plate excavated in front of cardinals, flattened behind ; ligament separated from chondrophore by a shelly wall; paUial sinus short, broad, not confluent below with the pallial Ime. Geologic range: Miocene to Recent. Anatina S. Renier' is said to be a nude name, and Anatina Lamarck, 1809- and 1812, are erroneous references, according to Iredale, as both refer to vernacular usages of the generic name. Anatina Lamarck, 1818, is a year later than Schumacher's Anatina and refers to a different shell. Labiosa Schmidt is much later and must be considered a syno- nym. We propose to use Anatina for the almost smooth group as well as for the inflated shells with prominent concentric ripples. Anatina, sensu stricto, will include only the shells that are almost smooth, having merely fine growth lines. These shells are generally smaller in size. The hinge of Anatina is suggestive of Schizothcerus. The latter, however, is larger and much heavier-shelled. Subgenus ANATINA, s. s. Shell sculptured with concentric striations, posterior end rostrated, with a radial ridge or plica- tion descendmg from the tunbo to the posterior ventral margin, and with the posterior dorsal margm reflected outward. Geologic range: Pliocene to Recent. The Pacific coast typical Anatinas are not well known. They may be represented by the type in the Recent fauna and by transmontana in the fossil. Anatina (Anatina) lineata (Say), of the Atlantic coast, occurs in the Pliocene of Florida. ^ Tavole per servire alia Classificazione e Connoscenza degli Animali, table 7, Padova, 1804, nomen nudem, fide Sherborn. 2 Philosophie Zoologiquc, p. 319, 1809. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 407 Subgenus RAETA Gray, 1853 Ructa Gray, Ann. Mag. Xat. Hi.st., Ser. 2, Vol. 11, p. 43, January, 1853; H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 386, 1856; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 882, 1898. Type (by monotypy), R. campechensis (Gray), 1825, = Lutraria canaliculata Say, 1822, = Liitraria plicatella Lamarck, 1818; New Jersey to Brazil; also Pleistocene of Florida. Shell rather large, convex, compressed posteriorly; sculpture of concentric plications, surface of fresh specimens vermiculate. Geologic range: Miocene to Recent. The most distinctive difference between Raeta and Anatina, s. s., is in the presence of evenly-spaced, concentric plications on the former in addition to the fine growth lines on the latter. The radial plication on the posterior portion of Anatina, s. s., is moved very near the posterior dorsal margin and is much subdued in Raeta. The dorsal margin of typical Raeta is not reflected. Anatina (Raetaj undulata (Gould) Plate 23, Figures 5a, 5b, 5c Lutraria umhihita Gould, Proc. Boston Soc. Nat. Hist., Vol. 4, p. 89, 1851; Boston Journ. Xat. Hist., Vol. 6, pp. 391, 392, pi. 15, fig. 7, 1853; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 211, 227, 232, 1857. Raeta undulata Gould, H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 386, 1856; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 535, 614, 640, 681, 1864. Labiosa undulata Gould, Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 157, 1894; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 191, pi. 21, fig. 11, 1924. Labiosa {Raeta) undulata Gould, Dall, Nautilus, Vol. 8, p. 41, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 177, 1903; Lamy, Journ. de Conchyl., Ser. 4, Vol. 11, p. 249, 1909; Vol. 17, p. 355, 1917. Anatina undulata Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 51, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924. Type locality: La Paz, Lower California, Mexico; Recent. Pleistocene: Questionably in the lower San Pedro series of Deadman Island, one "small fragment;" upper Pleistocene at Spanish Bight, San Diego (Arnold); upper Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: San Pedro, California, to Panama (Dall, 1921). Recent specimens of this species from La Paz, Lower California, Mexico, the type locality, have the umbones noticeably anterior to the middle of the shell. In the Stanford collection specimens labeled "San Pedro" which look like Pleistocene fossils have the umbones nearly medial. The Miocene form described below has the umbones posterior to the middle, being in this respect more like the Atlantic Anatina plicatella (Lamarck). The largest specimen of undulata we have seen came from La Paz and measures 119 mm. in length, 89 mm. in height, and the right valve has a convexity of about 32 mm. The concentric ripples are almost obsolete on the later formed parts of the shell. Anatina (Raeta) plicatella (Lamarck) Lutraria plicatella Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 470, 1818; Deshayes and Milne-Edwards Ed., Vol. 6, p. 93, 1835; Lamy, Bull. Mus. Hist. Nat., Vol. 19, p. .347, 1913. Lutraria canaliculata Say, Journ. Acad. Nat. Sci. Phila., Vol. 2, p. 311, 1822; Conrad, Amer. Mar. Conch., p. 46, pi. 10, fig. 1, 1831; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 211, 364, 1857. Mactra campechensis Gray, 1825 (?); in Wood, Index Testae. Suppl., pi. 1, fig. 3, 1828. Lutraria campechensis Gray, Loudon's Mag. Nat. Hist., New Series, Vol. 1, p. 375, 1837. Lamg7ion papyracea d'Orbigny, Voy. Amer. M6rid., Moll., p. 527, 1846, not of Chemnitz, fide Lamy, 1917. Raeta campechensis Gray, Ann. Mag. Nat. Hist., Ser. 2, Vol. 11, p. 43, 1853. Mactra canaliculata Say, Reeve, Conch. Icon., Vol. 8, Mactra, pi. 21, fig. 122, 1854. 408 San Diego Society of Natural History [Memoies Raetacanaliculata Say, H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 386, pi. 102, fig. 44a, 1856; Chenu, Man. Conchyl., Vol. 2, p. 62, fig. 251, 1862; Carpenter, Proc. Zool. Soe. London, for 1863, p. 368, 1863; Brit. Assn. Adv. Sci., Kept, for 1863, pp. 614, 640, 681, 1864. Lahiosa (Racta) canaliculata Say, Dall, Nautilus, Vol. 8, p. 28, 1894; Trans. Wagner Inst. Sci., Vol. 3, pp. 882, 907, 1898. Lahiosa {Raeta) plicatella Lamarck, Lamy, Journ. de Conchyl., Ser. 4, Vol. 17, pp. 353, 354, pi. 7, fig. 6, 1917. Shell with beaks posterior to medial point of valves; shape subovate, constricted behind. Recent: Caribbean and western Atlantic. Lamy (1917) has discussed this species and shown that canaliculata Say must fall into the synonymy of plicatella Lamarck. The type specimen of Lamarck's plicatella with the original label was found by Lamy in the Paris Museum and was figured by him in his Revision of the Mactridce. It is possible that Mactra papyracea Chemnitz^ is iden- tical with Lamarck's plicatella, but Chemnitz's names are not strictly binomial in the volume in which papyracea is described. Chemnitz gave the habitat of his species as Nicobar, in the East Indies; but this may be an error, as incorrect localities are common in the works of the older authors. The figure given by Chemnitz is of a shell with a more evenly rounded posterior end than Lamarck's type of plicatella has or than Recent speci- mens from Florida have, but this difference might be due to errors of delineation on the part of Chemnitz. All specimens as well as all figures of Anatina plicatella which we have seen show that the Atlantic species has posterior umbones and a rather ovate shape. The Pacific coast Recent undulata has anterior umbones; but the California Miocene form has posterior umbones like the eastern species, to which it is probably closely related. Anatina (Raeta) plicatella (Lamarck) variety longior, new variety Plate 23, Figures la, lb Shell like that of Anatina plicatella Lamarck but more elongate, less ventricose, with the pos- terior end more constricted, and an almost straight anterior dorsal margin. Length, 40 mm. ; height, 25 mm.; convexity (left valve), about 8 mm. Type specimen: San Diego Society of Natural History No. 192. Type locality: Superior Oil Company well, Ansolabehere No. 1, in Sec. 9, T. 29 S., R. 27 E., Mt. Diablo B. and M., depth, 4,525-7 feet, near Bakersfield, Kern County, California, upper Miocene (H. R. Gale). Miocene: At the type locality, upper Miocene of a well core near Bakersfield. One well-preserved specimen of an Anatina was secured from the core of a well drilled near Bakersfield. It was associated with Amianiis callosa variety stalderi (Clark), Glycymeris septentrionalis (Middendorff), Lucina nuttallii Conrad, Lucina excavata Car- penter, Macoma indeniata Carpenter (one specimen), Panope generosa Gould (one frag- ment), Solen sicarius Gould, Corbula luteola Carpenter, Polinices reclusianus (Deshayes), var. callosus (Gabb), Polinices diabolensis (Clark), Calyptrcea mamillaris (Broderip), OliveUa pedroana (Conrad), Nassarius antiselli (Anderson and Martin), A'', arnoldi (Anderson), and Mitrella tuber osa (Carpenter). This specimen is more elongate, has a more constricted posterior end, and more posterior beaks than Conrad's transmontana. 1 Neues Syst. Conch. Cab.. Vol. 6, pp. 233, 234, pi. 23, fig. 231, 1782. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 409 A. transmontana has approximately central beaks and fine, somewhat discontinuous, concentric sculpture. In the variety longior the umbo is a little more than a third of the total length of the shell from the posterior end. It is of much interest to note the closer relationship of this California Miocene Anatina with the Atlantic species than with the Pacific Recent undulata. It is a striking illustration of the Miocene intermigration between the Atlantic and Pacific faunas. Anatina (Raeta ?) transmontana (Conrad) Plate 22, Figure 2 Lulraria transmontana Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 8, p. .315, December, 1856; IT. S. Pac. R. R. Repts., Vol. 7, p. 194, pi. 5, fig. 6, 1857; Ball, U. S. Geol. Surv., Prof. Paper 59, pp. 175, 184, 1909, reproductions of Conrad's descriptions. Tyfe specimen: No. 13,322 in the U. S. National Museum. Type locality: "Rancho Triumpho, near Los Angeles;" Miocene. Miocene: Rancho Triumfo near the boundary between Los Angeles and Ventura counties, probably in the Topanga formation. Temblor Miocene; "Shore between San Luis and Santa Barbara" (Conrad, 1857). This species has approximately central beaks and numerous concentric growth lines. It does not seem to be closely related to the new form described above. Mr. S. Miiller kindly compared the type of longior with Conrad's type of transmontana in the U. S. National Museum. It is possible that transmontana should be assigned to the typical subgenus of Anatina. Conrad compared transmontana with his Lutraria papyria^ from the Eocene of Alabama, but the hinge of the latter is supposed to be sufficiently different to form the basis of a different genus, Pteropsis Conrad, 1860.- Genus RANGIA Desmoulins, 1832 Gnalhodon Gray, in Sowerby, Gen. Shells, No. 36, Dec, 1831 ; Gray, Proc. Zool. Soc. London for 1836, p. 104; Loudon's Mag. Nat. ffist., New Series, Vol. 1, p. 376, 1838: Dall, Nautilus, Vol. 8, p. 27, 1894; Proc. U. S. Nat. Mus., Vol. 17, pp. 89-106, pi. 7, 1894; Gill, Nautilus, Vol. 8, pp. 102, 103, 1895; not Gnalhodon Goldfuss, Handbuch der Zoologie, Abth. 2, p. 100, 1820, fide Gill. 1895. Rangia Desmoulins, Actes Soc. Lin. Bordeaux, Vol. 5, No. 25, p. 50, Feb. 15, 1832; H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 380, 18.56; Fischer, Man. Conchyl., p. 1095, 1887; Gill, Nautilus, Vol. 8, pp. 102, 103, 1895. Type (by subsequent designation, Gray, 1847), Rangia cyrenoides Desmoulins, = Gnathodon cuneatus Gray, in Sowerby, Gen. Shells, Pt. 36, figs. 1-3, 1831; also figured by Reeve, Conch. Syst., Vol. 1, p. 62, pi. 47, 1841 ; coast of Gulf of Mexico, Recent; also fossil in Pliocene of Florida, etc. Shell somewhat like that of Mulinia Gray, l:)ut with the laterals elongated, the anterior one hooked downward at the cardinal end. Geologic range: Tertiary to Recent, possibly Mesozoic. Distribution: North, South, and Central America and the Caribbean region; ? Europe ; in brackish or salt water. This genus is a deformed derivative of the Mactridce specialized for brackish-water conditions. 1 Fossil Shells of the Tertiary Formations of North America, Philadelphia, Vol. 1, no. 4, p. 41. 1833; reproduced by Harris, p. 67, (bottom pagination), pi. 19, fig. 1, 1893. According to Harris, the plate was never really published with the original text. ~ Dall described and discussed this genus in Trans. Wagner Inst. Sci., Vol. 3, p. 881, 1898. 410 San Diego Society or Natural History [ Memoirs Rangia lecontei (Conrad) Gnathodon lecontei Conrad, Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 2, p. 273, pi. 24, figs. 1-3, January, 1853; Proc. Acad. Nat. Sci. Phila., Vol. 7, p. 31. Rangia leconti Conrad, Proc. Acad. Nat. Sci. Phila., for 1860, p. 232, 1861. "Gnathodon mendicus Gould," Orcutt, West American Scientist, Vol. 12, p. 11, 1901; not of Gould, Proc. Boston Soc. Nat. Hist., Vol. 4, p. 88, 1851, as Mactra. Type specimen: In the U. S. National Museum, Catalogue No. 6,833. Type locality: Carrizo Creek, western Imperial County; Quaternary. Quaternary: Carrizo Creek, western border of the Colorado Desert, Imperial County. This species was reported in great abundance in a layer two feet thick along the bank of Carrizo Creek. It differs from Rangia mendica (Gould) in its elongate posterior lateral tooth and its more rounded shape. Rangia mendica (Gould) is the type of the section Rangianella Conrad, which is characterized by short lateral teeth that are feebly striated or smooth, by its somewhat elongate shape, and by its practically obsolete pallial sinus. R. lecontei, although it agrees in that its pallial sinus is obsolete, has the elongate teeth of typical Rangia. Superfamily Myacea Pelecypods usually with the l^urrowing habit, more or less inequivalve, hinges degenerate. Family MYACIDAE Shell with a large projecting spoon-shaped resilium-bearing process in the left valve and a shallow depressed socket in the hinge of the right corresponding to it ; teeth usually obsolete. Geologic range: Eocene to Recent. Genus MYA Linnaeus, 1758 Mya Linnaeus, Syst. Nat., Ed. 10, p. 670, 1758, species included are truncata, arenaria, and several others; Children, Quart. Journ. Sci., Lit., Arts, Vol. 14, p. 85, October, 1822, type cited Mya truncata Linnseus; "Mya L., 1758a, 670, type M. truncata L., 1758a, 670'' placed on the official list of generic names by Opinion 94 of the Interna- tional Commission on Zoological Nomenclature, published in the Smithsonian Misc. Coll., Vol. 73, p. 13, 1926. Type (by subsequent designation. Children, 1822), Mya truncata Linnseus. Shell of medium average size, elongate trigonal or ovate, rounded anteriorly, somewhat angular and strongly gaping posteriorly ; sculpture of concentric growt h Imes or ridges and very faint radiating irregularities; hinge of left valve with a conspicuous projecting spoon-shaped chondrophore bordered by elevated ridges and often with an additional minor ridge posteriorly ; hmge of right valve with a depressed, excavated chondrophore, attached posteriorly to the interior wall of the shell; dorsal margins of both valves conspicuously strengthened, that of the right valve fitting over the left; pallial sinus large, with a blunt rounded end extending horizontally to about the center of the shell. Geologic range: Eocene to Recent. Distribution: Cold and temperate waters of all oceans. Subgenus MYA, s. s. External sculpture of shell very weak. The typical form of this genus resembles Schizotha^rus in appearance and habits, but the latter has a raised chondrophore in each valve and remnants of Mactroid teeth. Both are mud burrowers, gaining their food through long projecting siphons, and both are typical cold-water groups. Mya can stand a considerable amount of brackishness in Volume I] PLIOCENE AND PLEISTOCENE ]\IOLLUSCA OF CALIFORNIA 411 the water, often living at heads of bays and in estuaries where a large amount of fresh water is being brought in by rivers. The species of the typical subgenus are all closely related. The two extreme forms, arenaria and iruncata, are quite distinct; but there are a number of intermediate forms that have received various names and are difficult to separate. Mya arenaria is used considerably in the East for food, and has been studied by the U. S. Fish Commission. One of the Fish Commission papers deals with the development and living conditions.' Mya (Mya) arenaria Linnaeus Mya arenaria Linnaeus, Syst. Nat., Ed. 10, p. 670, 1758; W. Wood, General Conch., Vol. 1, p. 91, pi. 17, fig. 3, 1815; Grewingk, Russisch-Kaiserliche Mineralogische Gesellschaft zu St. Petersburg, Verhandlungen for the years 1848 and 1849, p. 356, pi. 6, figs. 3, a-c, 1850; S. V. Wood, Men. Palseo. Soc, Vol. 9, Crag Moll., Vol. 2, p. 279, pi. 28, figs. 2a-/, 1857; Gould, Invert. Mass., Binney Ed., p. 55, fig. 375, 1870; Sowerby in Reeve, Conch. Icon., Vol. 20, Mya, pi. 1, species 1, 1875; Dall, Bull. 37 U. S. Nat. Mus., p. 70, pi. 49, fig. 9, pi. 55, fig. 2, pi. 69, fig. 2, 1889; Cooper, Calif. St. Mining Bureau, Bull. No. 4, p. 29, 1894; Dall, Wa.sh. Acad. Sci., Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 117, 1904, re-issued by Smithsonian Inst. 1910; Thompson, Rept. B. C. Commissioner of Fisheries for 1912, pp. 1-40, 1-47, pi. 6, 1913; Dall, in Moffitt, Bull. 533 U. S. Geol. Survey, pp. 46, 47, 1913; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 283, pi. 29, figs, la, lb, pi. 52, 1918; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 56, pi. 17, figs. 2, 3, 1920; Dall, Bull. 112, U. S. Nat. Mus., p. 53, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 198, pi. 32, figs, la, lb, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 75, 1929. Mya hemphilli Newcombe, Proc. Calif. Acad. Sci., Vol. 5, p. 415, 1874; Stearns, American Naturalist, pp. 362-366, 1881; Science, New Series, Vol. 9, pp. 657-58, 1900. Shell of medium size, elongate, anterior end broadly rounded, posterior margin sloping down- ward in a broad gentle curve to a more or less rounded or acute point, beaks about in the middle of the shell, or varying somewhat, sometimes considerably to either side. This species is the normal species of Mya. It burrows in the sand or mud and varies considerably in shape according to the nature of the material around it. It also varies into what appear to be distinct races or varieties, the form truncata alone having departed sufficiently to be called a different species; and even truncata is connected by several intermediate forms. M. arenaria varies in the relative depth of the shell, in the position of the beak, in the acuteness of the posterior point, etc. Numerous synonyms have been described besides the one cited above. An interesting variety was described by Sowerby from the British Crag as Mya lata.- It has a ridge or fold following the normal curve of the posterior dorsal margin; but in addition, it has a wing-like dorsal extension which projects back of the normal posterior point and is abruptly truncated. In other words, it is a variety intermediate between arenaria and truncata. Another variety, with a more rounded posterior extremity, was described by Dall as intermedia; but as the name intermedia is preoccupied and an older name seems to be close enough to be applicable, this variety is here recorded as japonica. Still another variety, with a shorter, deeper shell was named crassa by Grewingk; but as this name is also preoccupied it is here recorded as the variety profundior. An unnamed variation represented by a Recent speci- men in the Oldroyd Collection at Stanford University from Long Island, New York, has a shell with the typical shape but with about three times the thickness. Toward the limits of the specific distribution all the varieties become much smaller. * Kellogg, J. L.: "Conditions Governing the Existence and Growth of the Soft Clam (Mya arenaria)," U. S. Commission of Fish and Fisheries, Rept. of Commissioner for 1903. pp. 195-224. pis. 7-10. 1904. 2 Mya lata Sowerby, Min. Conch. Gt. Brit., Vol. 1, p. 185, pi. 81, fig. 1, 1814. 412 San Diego Society of Natural History [Memoirs Variety arenaria, s. s. Shell elongate, ovate or acutely pointed posteriorly. Dimensions: Length, 87 mm.; altitude, 50 mm.; convexity (of two valves), 25 mm. Specimens are kllo\^^^ with a length of 135 mm. from the Atlantic. Type specimen: In London. Type locality: Northeastern Europe. ? Miocene: Of Unga Island, Alaska (Grewingk; Dall, 1904). ' Pliocene: Of Center Creek, Alaska (DaU, 1913) ; of the Red Crag and later deposits in England (S. V. Wood) ; uppermost Pliocene of Sicily (S. V. Wood); of Ventura Co., California (Waterfall); of the San Joaquin basin (Cooper, 1894). Pleistocene: England and continental Europe (S. V. Wood). Living: Britain, Scandinavia, Greenland, Atlantic Coast of North America south to Carolina, Alaska south to Japan and to Vancouver Island, British Columbia (found in Indian mounds on Vancouver Island, fide Oldroyd), artificially introduced about 1865 from the Atlantic Coast with seed oysters into San Francisco Bay whence it has spread along the California and Oregon coasts. It appears that the typical variety in migrating around through the Arctic changed its form somewhat so that Dall (1904) questioned whether the Pacific coast occurrences could be called typical. Nevertheless, some Japanese specimens are unquestionably the same as those from the Atlantic, and the specimens figured by Grewingk and by Oldroyd seem to be within the limits of variation of the typical form. It is hard to explain why the species did not migrate southward to San Francisco naturally, since it has thrived so well there after artificial introduction. Perhaps the northern race had adapted itself to cold- water conditions so that it could no longer return to the warm; and if so, it should be separated varietally and included perhaps with the next variety. The form introduced into San Francisco Bay received the name hemphilli. Mya (Myaj arenaria Linnaeus variety japonica Jay Plate 21, Figure 13 Mya japonica Jay, in Perry's U. S. Japan Exped., Vol. 2, p. 292, pi. 1, figs. 7, 10, 1857; Arnold, Bull. 396 U. S. Geol. Survey, pp. 42, 43, pi. 29, figs. 7, 8, Jan. 15, 1910, figures reprinted in Bull. 398, pi. 51, figs. 7, 8, 1910; Nom- land, Univ. Calif. Publ. Geol., Vol. 10, pp. 214, 219, 1917. Mya intermedia Dall, Trans. W.agner Inst. Sci., Phila., Vol. 3, p. 857, 1898; Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919; Canadian Arctic E.\ped., Vol."8, p. 29A, 1919; Bull. 112 U. S. Nat. Mus., p. 52, pi. 4, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 199, pi. 15, fig. 5, 1924; not Mya intermedia Sowerby, Min. Conch. Gt. Britain, Vol. 1, p. 173, pi. 76, fig. 1, 1814; Vol. 5, p. 20, pi. 419, fig. 2, 1823, Eocene (?) of Great Britain. Mya "Iruncata Linnaeus," Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 214, pi. 5, fig. 46, 1909, fide Dall, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 312, 1922, ? Mya dickersoni Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 478, pi, 63, figs, 3, 4, 1915; Nomland, Vol, 10, p, 300, 1917. Shell like that of the typical variety but somewhat shorter, with more roxmded extremities; when large, apt to have a coarser, heavier shell. Dimensions (average of Dall's Alaskan specimens) : Length, 115 mm. ; altitude, 75 mm.; convex- ity of two valves, 45 mm. Puget Somrd specimens are only about 30 imn. long. Type specimens: In the U. S. National Museum (?). Tyj}e localities: Of japonica, Volcano Bay, Island of Yedo, Japan; of intermedia, Alaska. ? Miocene: Unga Island, Alaska (see typical variety) ; upper Miocene of middle California (Clark, Nomland); "Quillayute Pliocene," Empire formation of Washington (Reagan; DaU, 1922). Pliocene: St. George Island, Alaska (Dall, 1919); middle and upper Etchegoin, uppermost Pliocene of middle California (Arnold; Nomland). Pleistocene: Bernard Harbor, .\rctic Circle (Dall, 1919); etc. Living: Arctic Ocean to Japan and to Monterey, California; probably also Atlantic. 1 Eic-hwald has questioned this age. See the note to the variety profundior. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 413 This variety is the commonest form of arenaria in the northeastern Pacific, and it probably was so in the upper Pliocene when it was very common in the San Joaquin embayment. It is a typically cold water form, growing very large and heavy in Alaska, but diminishing in size southward. Its great abundance in the uppermost Pliocene of the San Joaquin embayment, a few of the specimens reaching a respectable size (the one figured is 70 nmi. in length), is very significant, indicative of the colder climate of the time and confirming the correlation of the Myajaponica zone with the cold Santa Barbara zone along the open coast. The form japonica is distinguished from typical arenaria by its somewhat shorter, coarser, rougher shell. It is intermediate between arenaria and truncata. Jay, Dall, and Clark all stress differences in the chondrophore. Jay says "the tooth more thickened," . . . "its outer face divided near the posterior side by a deep furrow, and the anterior edge turned up in shape like a tooth." Dall says "there are constant though not conspicuous differences in the hinge". Clark states "that the posterior ridge on the chondrophore extends out beyond the edge." The present writers find that the character of the chondro- phore varies somewhat, and that in this respect the form japonica of Jay, the Etchegoin specimens of Arnold, and dickersoni of Clark agree better with the typical arenaria than does Dall's intermedia. However, there are some Etchegoin specimens on which the pos- terior ridge of the chondrophore does not project and the furrow is not deep; and there are some living specimens with the intermedia shape that have a projecting posterior ridge separated by a furrow. In other words, there is a criss-cross combination of the characters of shell shape and chondrophore ridge, so that one or the other or both must be considered unreliable. Similarly, the size and shape of the pallial sinus vary without respect to the other shell characters. In view of the slight differences between arenaria and japonica, the difficulty of telhng them apart, the wide and practically coincident distribution of the two forms (although arenaria is said to five in shallower wa.ter,j apojiica being intermediate in this respect also between arenaria and truncata), and in view of the fact that the char- acters are very variable and intergrade and appear in different combinations, it seems advisable to treat the two forms as no more than ecologic or geographic varieties of the same species. Some of the Uving forms of arenaria along the coasts of Washington and British Columbia have the characters of typical arenaria; and if it be stated that they are representatives of the Atlantic coast form migrating northward from San Francisco, it can be answered that if so, they have in this short time come to look so much like their native brothers that in the course of a geologic age they would become indistinguishable, thus showing the nature of their differences to be Hke those of geographic varieties, not yet great enough to make them separate species. The chondrophores of all the varieties of arenaria differ from those of truncata in being more spoon-shaped, more rounded at the end, whereas those of truncata are shorter, somewhat trigonal, cut off with but a gentle curve at the end, and the posterior ridge never projects and is not separated from the chondrophore by a deep furrow. M. truncata is also distinguished by its less sloping dorsal margins, which extend almost straight posteriorly and then turn abruptly at the broad, bluntly rounded, squarely truncated, or even concave posterior extremity. The young, however, are difficult to distinguish, both being rounded and elongate. The young are also difficult to distinguish from Cryptomya, the differences being that the young typical Myas are somewhat more elongate and that on Recent material the pallial sinus can be seen even on very small individuals. 414 San Diego Society of Natural History [Memoirs Mya (Mya) arenaria Linnaeus variety profundior, new name Mya crassa Grewingk, Russisch-Kaiserliche Mineralogische Gesellschaft zu St. Petersburg, Verhandlungen for the years 1848 and 1849, p. 355, pi. 6, figs. 2a-d, 1850; Dall, Wash. Acad. Sci., Alaska, Res. Harriman Alaska E.\ped., Vol. 4, p. 117, 1904, reissued by Smithsonian Inst., 1910; not Mya crassa Vallot, Exer. Hist. Nat., p. 7, 1801; nor Mya crassa Wood, General Conchology, p. 106, pis. 20, 21, 1815, a Unio. Shell like that of the typical variety but relatively much shorter and deeper. Dimensions: Length, 83 mm. ; altitude, 103 mm. ; convexity of the two valves, 53 mm. Type specimen: At Leningrad (?). Type locality: Probably on the southeast coast of the Peninsula of Alaska near the settlement at Pavloff, where Grewingk says it is common. Horizon Miocene according to Dall.i Miocene: Of various places in .\laska, the type locality, also at Morshovsky Bay, Moller Bay, and on Kadjak and Unga islands (Grewingk; Dall). This may be but an unusual variation of the form for which Dall used the preoccupied name intermedia; and if it is decided to separate the latter horn japonica and dickersoni, it may be possible to use this name for it. These varieties are all very closely related, Dall stating in 1904 that this very deep, heavy form intergrades with the elongate form called by Grewingk arenaria; and yet it is much closer to Dall's own form intermedia. It is characterized by its extreme depth, having a greater depth than length, as can be seen by the dimensions which are the reverse of those of the other varieties. Grewingk had several specimens with these proportions. The hinge appears to be like that of Dall's intermedia. The posterior dorsal margin slopes off abruptly, not at all like that of truncata. Mya (Mya) truncata Linnaeus Mya truncata Linnaeus, Syst. Nat., Ed. 10, p. 670, 1758; W. Wood, General Conchology, Vol. 1, p. 90, pi. 17, figs. 1, 2, 1815; Grewingk, Russisch-Kaiserliche Mineralogische Gesellschaft zu St. Petersburg, Verhandlungen for the years 1848 and 1849, p. 356, 1850; S. V. Wood, Mon. Pala30. Soc, Vol. 9, Crag Moll., Vol. 2, p. 277, pi. 28, figs, la-/, 1857; Gould, Invert. Mass., Binney Ed., p. 58, fig. 376, 1870; Sowerby in Reeve, Conch. Icon., Vol. 20, Mya, pi. 1, species 4, 1875; Dall, Wash. Acad. Sci., .\laska, Res. Harriman Alaska Exped., Vol. 4, pp. 117, 121, 1904, reissued by the Smithsonian Inst., 1910; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 545, pi. 50, fig. 1, 1907, figure reproduced in Bull. 309, U. S. Geol. Survey, pi. 40, fig. 1, 1907; Dall, Prof. Paper 59 U. S. Geol. Survey, p. 132, 1909; Arnold and Hannibal, Proc. Amer. Phil. Soc, Vol. 52, pp. 590, 596, 598, 1913; Dall in Moffit, Bull. 533 U. S. Geol. Survey, p. 46, 1913; Baker, Bull. Amer. Mus. Nat. Hist., Vol. 41, p. 499, 1919; Dall, Canadian Arctic Exped., Vol. 8, p. 29A, 1919; Bull. 112 U. S. Nat. Mus., p. 52, 1921; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 197, pi. 10, fig. 4, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Mya prsensa Gould, Proc. Bost. Soc. Nat. Hist., Vol. 3, p. 215, 1850; U. S. Exploring Exped. (Wilkes), Vol. 12, p. 385, 1852, Mollusca ,\tlas, pi. 33, figs. 498, a, h, 1856; Sowerby, in Reeve, Conch. Icon., Vol. 20, Mya, pi. 2, species 7, 1875; Dall, U. S. Geol. Survey, 17th Ann. Rept., p. 845, 1896. Mya "japonica Jay," Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 2.52, 1916 {fide Howe). Shell of mediinn size, elongate, dorsal margiias extending nearly in a straight line parallel to the ventral margin, the beaks rising somewhat above them, anterior end broadly rotmded, posterior end somewhat narrower and longer, with a bluntly roinided, squarely trimcated, or even concave extremity; sculpture of irregularly tmdulating growth lines; chondrophore of left valve shorter, broader, shallower, and with more angulated corners than that of arenaria, the posterior ridge sep- arated from the main hollow of the chondrophore by a shallow furrow and smaller ridge, but not so clearly so as in arenaria, not extending beyond the edge of the chondrophore, the rest of the mterior as in arenaria; pallial sinus very variable. Dimensions: Length, 65 mm.; altitude, 45 mm.; convexity of the two valves, 30 mm. 1 While this was in galley proof, the writers found at the California Institute of Technology a photostat copy of an .article by Eduard von Eichwald entitled "Die Miocan- und Kreideformation von Alaska und den Aleutischen Inseln," from the I\. Akademie d. Wissenschaften, St. Petersburg, 1.S71. In this paper Eichwald attributes all of Grewingk's Miocene mollusks to the Turonian Cretaceous, mentioning crassa on p. 124, and renaming Grewingk's Mya arenaria on p. 119 Anatina etegans. Perhaps the name eleyans could be used instead of profundior. Eichwald found a considerable number of .A.mmonites, but it seems hardly possible that he could have found Grewingk's pelecypods in the same beds. Compare the note to Nuaila ermanni, p. 117. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 415 Type specimen: In London (?). Type locality: Europe. Miocene: Near the settlement at Pavloff in the Peninsula of Alaska (Grewingk ; Dall, 1904) ; Empire formation of Oregon (Dall, 1909; Arnold and Hannibal; Howe). Pliocene: Coralline and Red Crags, England (S. V. Wood); Alaska (Dall); Elsmere Canyon, Los Angeles Co., California (Arnold); lower Etchegoin of the Federal Exploration Co. well Kinsella No. 1, Tulare Co., Calif., one hinge plate (H. R. G.); Wildcat formation of northern California (Martin); upper Pico of Ventura Co. (Waterfall). Pleistocene: Of boreal regions generally (Dall). Living: Circumboreal, in the Atlantic south to Great Britain and Massachusetts, in the Pacific south to Puget Sound. This specie.s is usually smaller and more irregular than arenaria, and can be distin- guished by its truncated posterior end and its differently shaped chondrophore. It inhabits deeper water than arenaria. As in Great Britain, it occurs in California lower in the Pliocene section, indicating perhaps that it could go farther south in deeper water when the temperature was warmer. There is a curious short form of this species with a deformed appearance that has had an unusually wide distribution for such a form. It was originally found fossil at Udde- valla, southern Norway, and was called uddevallensis.^ Later it was found in the Clyde beds of England, and Lyell found and illustrated the same peculiar form from the Pleis- tocene along the Gulf of St. Lawrence, stating that it is still living in that region. It was to Lyell's illustration that Grewingk referred when he reported truncata from the Tertiary of Alaska and to which he compared M. crassa. However, the typical form is also known to occur in the Tertiary of Alaska, and Middendorff figures the typical form living. Subgenus PLATYODON Conrad, 1837 Platyodon, Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 235, 1837; Dall, Trans. Wagner Free Inst. Sci., Vol. 3, pp. 858, 885, 1898. Type (by monotypy), Mya (Platyodon) cancellata Conrad, living, California. Shell like that of the typical subgenus but with a smaller chondrophore, and sculptured with concentric ridges formed by emphasizing the growth lines; animal with armor on the end of the siphons as in Mya truncata. Until recently but one species has been known in this subgenus, but a larger, deeper form has just been discovered by Mr. Wiedey in the lower Miocene of San Luis Obispo County. The writers regard the minor differences in the sculpture and in the size of the chondrophore between Platyodon and the typical subgenus as not more than subgeneric in significance. Here as elsewhere the tendency is to subdivide genera until they no longer mean anything and are of no use in making identifications. Mya (Platyodon) cancellata Conrad Plate 24, Figures 3a, 36 Ml/a (Platyodon) cancellata Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, p. 2.36, pi. 18, fig. 2, 1837; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 285, pi. 29, figs. 2a, 26, 1918. Mya cancellata Conrad, Sowerby in Reeve, Conch. Icon., Vol. 20, Mya, pi. 2, species 8, 1875. Platyodon cancellatus Conrad, Carpenter^ Brit. Assn. Adv. Sci., Rept. for 1863, p. 637, 1864, reprinted Smithsonian Misc. Coll., No. 252, p. 123, 1872; Tryon, Struct, and Syst. Conch., Vol. 3, pi. 106, fig. 28, 1884; Cooper, 7th .A.nn. Rept. Calif. St. Mineralogist, p. 260, 1888; Keep, West Coast Shells, p. 208, fig. 177, 1888, 1892; Arnold ^ Mya truncata variety uddevallensis Smith, see .S. V. Wood. loc. cit.. fig. Ic; Lyell, Trans. Geol. Soc. London, Ser. 2, Vol. 6, p. 137. pi. 16, figs. 5, 6, 1842. 416 San Diego Society of Natural History [Memoirs Mem. Calif. Acad. Sci., Vol. 3, p. 179, 1903; Keep, West Amer. Shells, p. 90, fig. 80, 1904 ; p. 100, fig. 78, 1911 ; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 62, pi. 17, fig. 1, 1920; Dall, Bull. 112 U. S. Nat. Mus., p. 53, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 202, pi. 32, figs. 2a, 2b, 1924. Mya (Platyodon) cancellatus Conrad, Clark, Univ. Calif. Publ. Geol., Vol. S, p. 419, pi. 64, fig. 1, 191.5; Nomland, Vol. 10, p. 300, 1917. Shell of medium size, heavy, elongate, strongly convex, rounded anteriorly, beaks varymg in position from the middle to the posterior tliird of the shell, dorsal margins sloping about as in Mya arenaria, posterior end narrow, sometimes short, truncated; sculpture of lamelliform growth lines, averaging altogether about 80, and faint irregular radial lines, very fine and numerous; chondrophore of left valve small, narrow, bounded by strong ridges, especially the posterior, that of the right valve small, short, hidden mider the umbo, guarded on the posterior dorsal margin by a tooth-like por- jection; umbones strongly incurved, the beaks worn away by rubbing against the opposite valve; pallial sinus very variable, usually reaching about to the middle of the shell. Dimensions: Length, 67 mm.; altitude, 40 mm.; convexity of the two valves, 37 mm. Type specimen: At the Academy of Natural Sciences, Philadelphia (?). Type locality: Near Santa Barbara, California. Miocene: Santa Margarita-San Pablo of middle California (Clark; Nomland). Pleistocene: Upper San Pedro series of Deadman Island, San Pedro, and vicinity, Los Angeles Co. (Arnold) ; locaUties 40 and 74 S. D. S. N. H., near Goleta, Santa Barbara Co., eight specimens (U. S. G.). lAving: Baulinas Bay, middle California, to San Diego (Dall). This species is distinguished from the other species of Mya by its concentric sculpture, elongate, heavy, strongly convex shell, and smaller chondrophore. It is a little more southerly in range. Genus CRYPTOMYA Conrad, 1848 Cryptomya Conrad, Proc. Acad. Nat. Sci., Phila., Vol. 4, p. 121, Dec, 1848; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 859, 1898. Type (by monotypy), Sphoenia californica Conrad, Miocene to Recent, California. Like a small Mya but without the long protruding siphons and consequently with but a slight posterior gape and the pallial sinus obsolete or very short; shell small, ovate, not very convex; chon- drophore similar to that of Mya arenaria; interior of dorsal margins thickened. Geologic range: Miocene to Recent. Distribution: Gulf of Cahfornia to Japan. Various names have been proposed for forms of Cryptomya with slightly different shapes, but a study of the variations shown by series of specimens from single localities has led the writers to believe that there is but one widely distributed variable species in the eastern Pacific. Dr. Clark of the University of California and Dr. Hanna of the California Academy of Sciences have considered Cryptomya a subgenus of Mya. It is true that the two are closely related, and that with fossil specimens on which the pallial sinus is not visible it is sometimes impossible to tell a Cryptomya from a young Mya or one of the small Myas that occur sometimes abundantly, near the Umits of the distribution of their species. However, the lack of the long siphons, which indicates apparently some difference in the living habits, may be of sufficient significance to warrant the separation of a distinct genus. It is only a matter of degree, and neither view can be wrong. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 417 Ciyptomya califomica (Conrad) Plate 21, Figures 7, 8a, 8b, 11, Uo, 14/< Sphxnia califomica Conrad, Journ. Acad. Nat. Sci., Phila., Vol. 7, p. 234, pi. 17, fig. 11, 1837; Carpenter, Proc. Zool. Soc. London, p. 210, 1856. Cry-plomya califomica Conrad, Proc. Acad. Nat. Sci., Phila., Vol. 4, p. 121, Dec, 1848; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 637, 1864, reprinted in Smithsonian Misc. Coll., No. 252, 1872; Gabb, Geol. Survey, Calif., Palao., Vol. 2, p. 90, 1868-69; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 237, 1888; Keep, West Coast Shells, p. 205, 1888, 1892 ; Newcombe, Nat. Hist. Soc. Brit. Columbia, p. 43, 1893 ; Arnold, Mem., Calif. Acad. Sci., Vol. 3, p. 180, 1903; Keep, West Amer. Shells, p. 89, 1904; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 526, 1907; Eldridge and Arnold, Bull. 309 U. S. Geol. Survey, pp. 25, 26, 27, 153, 1907; Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 202, 1916; Martin, pp. 243, 251, 1916; Nomland, Vol. 10, p. 218, 1917; Dall, Nautilus, Vol. 32, p. 24, 1918; Bull. 112 U. S. Nat. Mus., p. 53, 1921; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, pp. 550, 563, 1922; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 199, 1924; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. IS, p. 78, 1929. Cryptomya ovalis Conrad, Proc. Acad. Nat. Sci., Phila., Vol. 8, for Dec, 1856, p. 314, 1857; U. S. Pacific R. R. Surveys, Vol. 6, p. 69, pi. 2, fig. 2, 1857, reprinted by Dall, U. S. Geol. Survey, Prof. Paper 59, pp. 174, 176, 1909; Arnold and Anderson, Bull. 322, U. S. Geol. Survey, p. 58, pi. 22, fig. 7, 1907; Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 4, pi. 55, fig. 7, 1907; Proc. U. S. Nat. Mus., Vol. 34, pp. 353, 354, pi. 36, fig. 9, 1908; Bull. 396 U. S. Geol. Survey, pp. 21, 24, 25, 27, 30, 34, 38, pi. 22, fig. 5, Jan. 15, 1910, reprinted in Bull. 398, pi. 44, fig. 5, 1910; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Nomland, Vol. 9, p. 81, 1916; Mar- tin, pp. 239, 243, 251, 1916; Dickerson, Proc. Cahf. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922. Mya califomica Conrad, Sowerbj- in Reeve, Conch. Icon., Vol. 20, Mya, pi. 1, species 3, 1875. Cryptomya orcgonensis Dall, Prof. Paper 59 U. S. Geol. Survey, p. 132, pi. 11, fig. 4, 1909; Arnold and Hannibal, Proc. Amer. Phil. Soc, Vol. 52, p. 596, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916. Cryptomya quadrata Arnold, Bull. 396 U. S. Geol. Survey, p. 71, pi. 21, figs. 2, 2a, Jan. 15, 1910, figures reprinted in Bull. 398, pi. 43, figs. 2, 2a, 1910; Nomland, Univ. Calif. Publ. Geol., Vol. 9, pp. 81, 202, 1916; Martin, pp. 245, 252, 1916; Nomland, Vol. 10, pp. 211, 218, 1917. Cryptomya washingtoniana Weaver, Bull. No. 15 Wash. Geol. Survey, p. 70, pi. 13, fig. 114, 1912. Mya (Cryptomya) ovalis Conrad, Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 479, pi. 60, figs. 3, 4, 1915; Nomland, Vol. 10, p. 300, 1917. Cryptomya tcashi ngtone7isis Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916. Mya [Cryptomya) califomica (Conrad), Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 284, pi. 31, figs. 2a, 2ft, pi. 53, 191S. Cryptomya magna Dall, West Amer. Scientist, Vol. 19, No. 2, p. 17, 1921 ; Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 15, pi. 13, figs. 3, 4, 1925. Mya inopia Hanna, Proc. CaUf. Acad. Sci., Ser. 4, Vol. 13, p. 172, 1924, unnecessary new name for C. ovalis. Macoma kerica Hendrickson, Ann. Rept. Calif. St. Oil and Gas Supervisor (Summary of Operations, California Oil Fields), Vol. 13, No. 7, pp. 13, 15, 16, 18, pi. 5, fig. 1, Jan., 1928. Shell rather small, not very convex, ovate, anterior end smoothly rounded, beaks not very prom- inent, varying somewhat in position, sometimes anterior, sometimes posterior to the middle, dorsal margms broadly roimded, beaks at the starting point of two, more abruptly sloping ridges, the pos- terior ridge more distinct and separated from the dorsal margin by a sulcus, posterior end bluntly truncated, with this sulcus meeting it about in the middle, practically no posterior gape, ventral margin gently curving; sculpture of fine growth lines, and, especially on small specimens, faint radiat- ing lines; chondrophore of left valve similar to that of Mya arenaria but somewhat shorter and broader, bordered by two strong ridges, the posterior separated by a famter ridge and sulcus from the main bowl of the chondrophore, sometimes projecting like a tooth; dorsal margins of both valves strongly reinforced ; the chondrophore of the right valve a weak partition joined to the interior of the shell by its upper and posterior sides and hidden under the beak in a broad hollow excavated in the thickened dorsal margin, the right valve fittmg over the left; pallial sinus very short and incon- spicuous, not passmg beyond the posterior muscle scar. Dimensions: Length, 30 mm.; altitude, 20 mm.; convexity of two valves, 11 mm. Type specimens: Of califomica and ovalis, at the Academy of Natural Sciences, Philadelphia (?); of orcgonensis, No. 153,931; of quadrata, No. 165,525; of magna, No. 333,127, in the U. S. National Museum; of ivashingtoniana, at the University of Washing- ton; of kerica, at the California Academy of Sciences. 418 San Diego Society of Natural History [Memoirs Type localities: Of californica, living near Santa Barbara; of ovalis, Monterey Co., probably Miocene; of oregonensis, Empire formation, upper Miocene, of Coos Bay, Ore- gon; of quadrata, Etchegoin formation. Pliocene of the Coalinga district, middle Cali- fornia; of ivashingtoniana, Montesano formation, upper Miocene of Washington; of magna, Pleistocene of San Quintin Bay, Lower California; of kerica, basal marine Pliocene, Cryptomya californica zone, of well cores in the southeastern end of the San Joaquin basin, California. U. Miocene: Montesano formation of Washington (Weaver); Empire formation of Oregon (Dall, 1909; Howe); Santa Margarita-San Pablo of California (Clark; Nomland, 1917). Pliocene: In practically every Pliocene region and horizon reported on in California, especially abundant in the basal marine Pliocene of the southeastern end of the San Joaquin basin. Pleistocene: Elk River beds, Oregon (Arnold and Hannibal) ; in practically every California locality, especially in the base of the Las Posas zone of the Ventura district; San Quintin Bay, Lower California (Dall, 1925; Jordan); Magdalena Bay (Dall, 191S). Laving: Alaska to Topolobampo, Mexico (Dall, 1921a), probably also Japan. Before working with this common species, it is well to examine several series of speci- mens from different localities, living and fossil, to see the variation. It will be seen that nearly all the shapes upon which the named forms are based are represented in each series of variations, but that in some collections the specimens are all or nearly all smaller than in others. This difference in size may be accounted for by differences in the suitability of the environments. The state of preservation has a great deal to do with the differences in the appearance of the fossil specimens. The name Mya inopia is unnecessary because there are several other names available for this species, even in case it were agreed that C. ovalis, originally so named, is preoccu- pied by Mya ovalis of several earlier authors when none of their species is now assigned to Cryptomya. If an attempt is made to separate the Miocene from the Recent form, the name oregonensis should be used for the former; and there are several more names for Pliocene forms, though it is inconvenient to have to identify the horizon before the species can be determined. The type of "Macoma" kerica is so poor that nothing can be learned by looking at it except that it is a small ovate pelecypod. However, it occurs abundantly, according to the description, in a zone associated with oil-bearing beds in the lower part of the marine Pliocene of the southeastern part of the San Joaquin basin, accompanied by characteristic "pebbles" of a gray color with a black surface coating. This same zone was recognized in the Fruitvale district, where Cryptomya californica is very abundant and Macoma is comparatively scarce. The "pebbles" appear to be nodules with the organic impurities concentrated on the surface. They break down readily in acid. Specimens from Japan in the Oldroyd Collection at Stanford University labelled C. ellipiica Adams are identical with the smaller specimens of C. californica. As the original of C. elliptical was said to come from Australia, and as the specimen figured by Sowerby shows a deep pallial sinus, the true elliptica is probably something else. Whether Mya mindoroensis Adams and Reeve, or C. truncata Gould, or some other name is the one now used for the Japanese Cryptomya, probably one or more of these western Pacific names should be added to the synonymy of californica. Conrad's Mya montereyana and Mya subsinuata, described and figured in the same places as C. ovalis, might also be synonyms, but it is impossible to tell what they are. ' Sphaenia ellipiica A. Adams, Proc. Zool. Soc. London, p. 88, 1850. 7 Mya ellipiica A. Adams, Sowerby in Reeve, Conch. Icon., Vol. 20, Mya, pt. 1, species 2, 1875. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 419 The former has a Mya-Cryptomya hinge and is rather small (IJ^ inches long); the latter has the shape of Conrad's Sangiiinolaria nuttallii, and does not show the hinge. It is quite likely that C. caUfornica is a direct descendant of Mya arenaria (or vice versa), for the two have many details of character in common that can hardly be all coincidences. The differences between them are all explainable as the effects of their having assumed different habits, the smaller shell having decided, probably some time during the Miocene, no longer to keep its siphons habitually extended. This relationship is a strong argument for including Cryptomya in the genus Mya. Genus SPHENIA Turton, 1822 Sphenia Turton, Conchylia Insularum Britannicarum, or The Shells of the British Isles, p. 36, 1822, species included are binghami Turton, sivainsoni Turton, and Mya dectissata Montagu; Gray, Proc. Zool. Soc. London, p. 190, 1847, type cited S. binghami; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 359, 1898. "S-phsena Turton;" "Sphienia Turton," of various authors. Type (by subsequent designation, Gray, 1847), Sphenia binghami Turton, op. ciL, p. 36, pi. 3, figs. 3, 4, pi. 19, fig. 3, 1822, living Torbay, England. Shell like that of a small Mya, very small, thin, irregular in shape, the chondrophore small, thin, oblique, practically characterless. Geologic range: Miocene ? to Recent. Distribution: Cold and temperate waters of the Atlantic and Pacific. This genus, as Dall points out, is barely separable from Mya. It is a small degenerate offshoot, with the nestling habit. Dall says that it has a deep pallial sinus, but the type specimen of Dall's Sphenia glabata in the Oldroyd Collection at Stanford University appears to have a sinus like that of Cryptomya. The interiors of the other species in the collection are not visible, or do not show the sinus. The posterior extremity is usually somewhat narrowed and drawn out, with a small gape. Specimens of this genus are distinguishable from small specimens of Saxicava by their chondrophore. There are one or more Pacific coast living species listed by Dall in Bulletin 112 of the U. S. National Museum (p. 53), probably with too many names. Gabb described a species from the "Miocene of Santa Barbara," but it was never figured, and it may not be a Sphenia.^ Family CORBULIDAE Shell small, thick, inequivalve, with a small posterior gape; sculpture sometimes discrepant; hinge generally with one stout cardmal tooth m the right valve and a smaller, nearly obsolete tooth in the left valve, each fitting into a fosset in the opposing valve; ligament subextemal, resilium in- ternal; pallial sinus nearly obsolete. Genus CORBULA Bruguiere, 1797 Corbula Bruguiere, Encycl. Meth., pi. 230, 1797, species figured but none named; Lamarck, Mem. Soc. Hist. Nat., Paris, p. 89, 1799, no species named; Syst. Anim. s. Vert., p. 137, 1801, several named species assigned to genus; Children, Quart. Journ. Sci., Lit., Arts, p. 301, January, 1823, Corbula nucleus Lamarck designated as type; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 836, 837, 1898; Gardner, Nautilus, Vol. 40, pp. 41-45, 1926. "Agina Turton," of some authors, not of Turton, Conchyl. Insul. Britan., Dithyra, p. 54, 1822, which = Saxicava. ' Sphxnia bilirata Gabb, Proc. Acad. Nat. Sci.. Phila., Vol. 13, p. 369, 1862. 420 San Diego Society of Natural History [Memoirs Type (by subsequent designation, Children, 1823),' Corbula nucleus Lamarck, = Corbula gibba (Olivi), Zool. Adriatica, p. 101, 1792, Mediterranean Sea and west coast of Europe: Recent, also fossil.'- Figured by Reeve, Couch. Icon., Vol. 2, Corbula, pi. 2, fig. lOfl, 105. 1843. Subgenus CORBULA, s. s. Shell generally small, subtrigonal; valves unequal, the right valve larger, obtusely rostrate pos- teriorly; umbones prosogyrous or erect, curved over; sculpture discrepant, the right valve with definite concentric ribs, the left with faint, widely spaced radials and sometimes indistinct growth strise; posterior end with a small gape; hinge of the right valve with a single stout cardinal tooth behind which is a large pit, hinge of the left valve with a protruding process in front of a pit, into which the cardmal of the right valve fits; laterals absent; ligament chiefly internal; pallial sinus very small. The subgenus Corbula, sensu stricto, includes "Aloidis Miihlfeldt" of Gray, Fischer, Cossmann, Bucquoy, Dautzenberg, and Dollfus, Woodring, and others, but not the true Aloidis, sensu stricto, of Megerle von Miihlfeldt.' The typical subgenus occurs as early as the Eocene in the region bordering the Gulf of Mexico and is represented in the Pliocene of California by Corbula binominata Hanna, and by a new species described below. Corbula (Corbula) gibbiformis, new species Plate 19, Figures 4, 5, 6 ? Cm-hula, n. sp., Merriam in Watts, Bull. 19, Calif. State Mining Bureau, p. 221, 1900. Shell of mediiun size, trigonal, plump; right valve strongly ventricose, with strong, concentric, closely-spaced riblets, left valve smaller, more elongate, with about five low, narrow, sharp radial riblets ; right hinge with one strong cardmal tooth beneath the curved-over umbo and anterior to a prominent pit; left valve with a pit and a low, tooth-like prominence posterior to it. Length, about 13 mm.; height, about 13 mm. Type specimens: Holotype No. 172, S. D. S. N. H.; paratypes Nos. 171 and 173 S. D. S. N. H., type collection. Type locality: Southern California Gas Company's well No. 1-4, Sec. 4, T. 28 S., R. 23 E., Kern County, depth 3951-2 feet, upper Etchegoin formation, upper Pliocene. Pliocene: At the type locality, upper Etchegoin; also collected by Alex. Clark in the Peclen coalingensis zone of the Kettleman Hills, Coalinga district, middle California, and at loc. 442 S. D. S. N. H., middle Pliocene of the Santa Clara Valley; ? near Camulos, Ventura Co. (Watts). This species has very much stronger concentric sculpture on the right valve than Corbula binominata Hanna. The latter species was described from poor material from ^ Stewart (Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 286, 1930) accepts Schmidt's designation (Vers. Einr. Conch. -Samml., pp. 57. 77, 177, 1818) of Corbula sulcata Lamarck, a Recent species from Senegal, figured by Bruguifire on pi. 230. figs, la, 16. Ic. and by Reeve, Conch . Icon., Vol. 2. Corbula, pi. 1, sp. 2, 1S43. Schmidt's designation is unfortunate, as it leaves the application of Corbula. s. s.. uncertain; but perhaps it may be disregarded, for on p. 57 he designated three species as types. If sulcata is accepted as type, Aloidis becomes an exact synonym (Jide Gardner). C. sulcata has the same shape as gibba (which is also shown on Brugui^re's plate, figs. 4a. 46), and the two species were retained in the same group by Bucquoy. Dautzenberg, and Dollfus; but sulcata appears to have well-developed concentric sculpture on both valves and is probably somewhat more closely related to Lentidium than is gibba. Gardner suggests that Csestocorbula Vincent (Ann. Soc. Roy. Zool. Malac, Vol. 44, p. 141, 1910), of which she says the type is C. henckeliusi Nyst, might be applicable to the gibba group. However. C. henckeliusiana Nyst (described in "Rech. Coq. Foss. Housselt," Mess. Sci. Arts Belg., Vol. 4, p. 144. 1S36, fide Sherborn, and referred to by Bronn as Nyst, p. 63, pi. 1, fig. 3) is said by Bronn (Index Palaeontologicus, Vol. 1, p. 335, 1850) to resemble cuspidata Sowerby. Bronn gives the age of henckeliusiana as Eocene and that of cuspidata as Miocene. The latter (Min. Conch. Gt. Brit., Vol. 4, p. 85, pi. 362, figs. 4. 5, fi, 1822) comes from the upper marine formation in Colwell and Whitecliff Bays on the Isle of Wight. Its valves are about equally sculptured with fine concentric lines, and it looks more like luteola than gibba. In case a new name is needed for the gibba group, we propose Varicorbuln, ^v-ith Corbula gibba (Olivi) as figured by Bucquoy, Dautzenberg, and Dollfus for the type. 2 Bucquoy, Dautzenberg, and Dollfus (Moll. Mar. Roussillon, Vol. 2, pp. 578-585, pi. 85, figs. 1-6, varieties figs. 7-23, 1890) have given a good discussion of this species and a long list of references. 3 Fide Gardner, Nautilus. Vol. 40, p. 43, 1926. Von Muhlfeldt's paper is not in any California library. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 421 the Pliocene fossil bed at Fourth Street and Broadway, Los Angeles. C. gibbiformis is very similar to C. gibba (Olivi) of the Adriatic Sea, but the California species has much coarser concentric ribs and is less elongate; otherwise the resemblance is striking. Corbula (Corbula) binominata Hanna Corbula tenuis Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 59, pi. 2, figs. 4a, ib, 1916; not Corbula tenuis Sowerby, Proc. Zool. Soc. London for 1833, p. 36. Corbula binominata Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 163, 1924, new name. Type specimen: In the University of California collection, No. 11,087. Type locality: Fourth Street and Broadway, Los Angeles; upper Pliocene. Pliocene: Excavation at corner of Fourth Street and Broadway, Los Angeles (Moody). There is some question about which valve Moody figured in his original description of this species. On the explanation to the plate his figure 4b is stated to be the left valve, but in the text he remarked that the "left valve is unknown." This figure shows faint concentric sculpture and no radial riblets. If it is a right valve the umbo is less broadly inflated and the sculpture much less prominent than that of C. gibbiformis. Subgenus LENXroiUM Cristofori and Jan, 1832 Lentidium Cristofori and Jan, Catal., Sect. 2, p. 8, 1832; Herrmaimsen, Indicis Gen. Malac, Vol. 1, p. 581, 1847; Gray, Proc. Zool. Soc. London for 1847, p. 191, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 838, 1898. Corbulomya Nyst, M6m. Cour., Acad. Roy. Sci. Brussels, Vol. 17, p. 59, 1845; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 308, 1847; Bucquoy, Dautzenberg, and DoUfus, Moll. Mar. Roussillon, Vol. 2, p. 585, 1896. Type (by subsequent designation, Dall,^ 1898), Lentidium maculatum Cristofori and Jan, = Corbula mediterranea (Costa), Catal. Test. Sicil., pp. xiv, xxvi, 1829, ^de Montero- sato, Nomen. Gen. Spec. Conch. Medit., p. 30, 1884; figured by Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 585, pi. 85, figs. 24-29, 1896; Mediterranean Sea; Recent. Shell nearly equivalve, elongate trapezoidal, with concentric sculpture on both valves, often rather feeble ; ligament sometimes visible externally in a fissure near the umbo. Corbula (Lentidium) luteola Carpenter Plate 19, Figures 2, 7 Corbula luteola Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 637, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 236, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 181, pi. 17, fig. 11, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 53, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 203, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 154, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Corbula luteola var. rosea Williamson, BuU. So. Calif. Acad. Sci., Vol. 4, p. 120, 1905; not Corbula rosea Leach in Brown, 1844. Shell small, elongate, thick, nearly equivalve, left valve shghtly smaller; beaks subcentral, slightly posterior; anterior end evenly rounded, posterior end somewhat bluntly trmacated, a blunt ridge extending from near umbo to posterior ventral margin ; sculpture on both valves of fuie concen- tric ridges; right valve with a promment cardinal tooth in front of resilial pit, left valve with a small cardinal projection; pallial sinus very small, nearly absent; adductor impressions relatively large, distinct from pedal scar. Size variable; length, 9.5 mm.; height, 6..5 mm.; convexity of matched valves, 4 mm. ' Both Herrmannsen and Gray cited Corbula mediterranea as the generic type. The present authors have been unable to see Cristofori and Jan's Catalcgus, but as it seems unlikely that those authors mentioned Corbula mediterranea, the type designation has been given as of Dall. The uncertainty does not affect the subgenus. 422 San Diego Society of Natural History [Memoirs Type locality: Between San Diego and San Pedro; Recent.. Upper Miocene: Well cores near Bakersfield (H. R. G.)- Pleistocene: "Pliocene" of Deadman Island; lower San Pedro series at Deadman Island and San Pedro; upper San Pedro series at San Pedro and Los Cerritos [Los Cerritos = ? lower Pleistocene]; foot of Twenty-sixth Street, San Diego (Arnold); low terrace near beach at Seacliff station, about eight miles northwest of Ventura (Stanford collection); Santa Monica palisades (coll. by E. C. Clark); upper Pleistocene at San Ignacio Lagoon and at San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926). Recent: Monterey, California, to Acapulco, Mexico (Jordan, 1924). This is the common Corbula of the southern Cahfornia coast. The variety rosea WiUiamson has no significance whatsoever. Pinkish or rosy-colored individuals occur indiscriminately associated with the yellowish form. The name rosea was used for a Corbula^ many years before Williamson used it. Corbula (Lentidium) fragilis Hinds Corbula fragilis Hinds, Proc. Zool. Soc. London for 1843, p. 56, Nov., 1843; Reeve, Conch. Icon., Vol. 2, Corbula, pi. 3, fig. 19, January, 1844; Hinds, Zool. Voy. Sulphur, Moll., p. 68, pi. 20, fig. 11, 1845; Dall, U. S. Nat. Mus., Bull. 112, p. 53, 1921; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, pp. 560, 563, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 203, 1924. Type locality: West coast of Veragua, Mexico, found in mud at a depth of eighteen fathoms (Hinds). Pleistocene: Tomales Bay, Marin County, California (Dickerson). Recent: Monterey, California, to Salina Cruz, Mexico (Dall). This species, as figured by Reeve, is more narrowly produced posteriorly than Cor- bula luteola Carpenter, has more prominent concentric sculpture, and averages a little larger. A Recent specimen in the Oldroyd collection from west Mexico is not so nar- rowly produced posteriorly and has less elevated umbones than the specimen figured by Reeve. It looks much like luteola except that it is larger, thinner shelled, and has more prominent concentric sculpture. C. luteola may be a less vigorous northern variety. Dickerson reported Corbula fragilis abundant in a clay bed of the Millerton forma- tion near Tomales Bay, Marin County, north of San Francisco. Corbula (Lentidium) porcella Dall Corbula porcella Dall, Proc. U. S. Nat. Mus., Vol. 52, p. 415, 1916; U. S. Nat. Mus., Bull. 112, p. 54, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 204, 1924; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Type specimen: In the U. S. National Museum, No. 97,039. Type locality : Off Lower California, Mexico ; in 44 fathoms, mud bottom. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Type locality. This name was applied to an unfigured shell dredged off Lower California. No comparison was given with the other species of the region, and the name is likely to be a synonym of some older one. ' Corbula rosea (Leach MSS.) Brown, lUustr. Conch. Gt. Brit., Ed. 2, p. 103, pi. 42, fig. 6, 1844. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 423 Family SAXICAVIDAE Shell of medium size or large, rather elongate, somewhat earthy like Mya, gaping at each end, w-idely at the posterior end ; valves equal or nearly so, sometimes not completely covering the animal ; cardinal areas not differentiated; sculpture rude, often of concentric ripples; hinge without lateral teeth and with one or two small cardmal teeth, or edentulous, and with a developed numph or pro- duced flange acting as a base for the posterior external ligament; adductor scars and pallial sinus irregular. Genus PANOPE Menard, 1807 Gbjcimeris Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 83, 1799; H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 350, 1856, as of Ivlein: not Glycymeris Da Costa, Brit. Conch., p. 168, 1778. Panope Mf^nard de la Groye, Mcmoire sur un Nouveau Genre de Coquille bivalve-equivalve de la Famille des Solen- oides, pp. 16, 30, January, 1807, fide Dall, Proc. Malac. Soc. London, Vol. 10, p. 34, 1912; Menard de la Goye, Journ. de Physique, Vol. 65, p. 114, .August, 1807; not Panope Leach, in Brewster's Edinburgh, Encylc, Vol. 7 (2), p. 404, 1814, Crustacea. Pnnopea Menard, Ann. Mus. Hist. Nat. Paris, Vol. 9, p. 135, 1807; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 827, 1898. Pampiea Lamarck, Extr. Cours Zool., p. 108, 1812; Hist. Nat. Anim. s. Vert., Vol. 5, p. 456, 1818; Children, Quart. Journ. Sci., Lit., Arts, Vol. 14, p. 84, 1823; Hist. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 6, p. 65, 1835; Tryon, Struct. Syst. Conch., Vol. 3, p. 136, 1884. Glycymeris Lamarck, Fischer, Man. Conch,, p. 1125, 1887. Type (virtually by monotypy, designated by Children, 1823), Panope aldrovandi Menard = Panope glycimeris (Born), described as Mya, Index Mus. Cses. Vind., p. 10, 1778, figured by Born, Test. Mus. Cses. Vind., p\ 1, fig. 8, 1780; also figured by Reeve, Conch. Icon., Vol. 19, Panopcea, pi. 1, 1873; Mediterranean Sea. Shell of moderate size or large, elongate, ventricose; umbones not very prominent, subcen- tral; rudely concentrically sculptured; gaping widely behind, slightly m front; hinge with one small cardinal tooth in each valve beneath the umbo, anterior to a large numph or ligamental ridge. In 1778 Da Costa used the generic name Glycymeris for the taxodont mollusks which Lamarck later named Pectunculus. Later Lamarck proposed the name Glycimeris, spelled with one "y," for the Saxicavoid burro wers now so generally called Panope. This latter name was erected by Menard de la Groye as a substitute for Glycimeris Lamarck, 1799, not Glycymeris Da Costa, 1778. Unfortunately, the International Rules of Zoolog- ical Nomenclature do not define how different the spelling of two generic names must be to avoid being considered homonyms. Legally, therefore, Glycimeris Lamarck, 1799, is not preoccupied by Glycymeris Da Costa, and hence should be used for the Saxacavoid burrowers; but as this would be so undesirable, it has been dropped in favor of Panope Menard, a step which will no doubt be approved by a definite suspension of the rules. According to Dall, Menard published a separate of his paper on Panope, dated Jan- uary, 1807, in which the name ends with the single vowel "e," the abridged paper with Panopea appearing later in the Annales of the Paris Museum. The cardinal teeth of Panope are variable in development. They may l)e almost obsolete, or thin but projecting prominently. The cardinal tooth of the left valve pro- jects more than that of the right valve. Panoynya tends to have less well developed teeth. Subgenus PANOPE, s. s. Shell large, the medial region evenly ventricose without a radial dejiressed area. Typical Panope lacks the depressed medial ara of Panomya and is considerably larger. The differences do not seem to be more than subgeneric. 424 San Diego Society of Natural History [ Memoibs Panope (Panope) generosa Gould Plate 21, Figures 12a, 126 Mya abrupta Conrad, U. S. Exploring Exped. (Wilkes), Vol. 10, p. 723, Geol. Atlas, pi. 17, fig. 5, 1849, = Panope ahrupla (Conrad) ; not Pholadomya abrupta Conrad, Foss. Shells Tert. Form. N. A., Vol. 1, no. 2, p. 26, pi. 12, Dec, 1832; republished by Harris, same figures, Washington, 1893; Conrad, Foss. Medial Tert., p. 3, pi. 1, fig. 4, 1838; republished by Wagner Free Inst. Sci., Philadelphia, same figures, 1893; = Panope (Margaritaria) abrupta (Conrad), the type of Margaritaria Conrad, Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 1, p. 214, July, 1849. Panopxa generosa Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 215, 1850; U. S. Exploring Exped., (Wilkes), Vol. 12, p. 385, 1852, Atlas Moll., pi. 34, figs. 507, 507a, 5076, 1856; Keep, West Amer. Shells, p. 90, fig. 81, 1904; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 205, pi. 15, figs. 1, 2, 3, 1924. Glycimeris generosa Gould, H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 350, 1856; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, pp. 89, 90, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 241, 1888; Keep, West Coast Shells, p. 209, fig. 178, 1888. Glycimeris estrellanus Conrad, U. S. Pac. R. R. Repts., Vol. 7, p. 194, pi. 7, fig. 5, 1857. Panopea abrupta Conrad, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 830, 1898. Panopea generosa Gould, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 830, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 182, 1903; Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 188, pi. 3, fig. 20, 1909; Arnold, Bull. 396, U. S. Geol. Surv., pp. 31, 142, pi. 18, fig. 4, 1910; Bull. 398, pi. 40, same figures, 1910; Keep, West American Shells, Revised Ed., p. 101, fig. 79, 1911; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 154, 1924; Waterfall, Univ. Calif. Publ. Geol., Vol. IS, p. 78, 1929. Panopea generosa var. soMa Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 831, 1898; U. S. Nat. Mus., Bull. 112, p. 54, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 206, pi. 3, fig. 11, 1924. Panopea generosa var. globosa Dall, op. cit., p. 831, 1898. Panopea estrellana Conrad, Arnold, Bull. 396, U. S. Geol. Surv., p. 64, pi. 15, fig. 1, 1910; Bull. 398, pi. 37, same figure, 1910. Panope generosa Gould, Kew, Univ. CaUf. Publ. Geol., Vol. 8, p. 46, 1914; English, Vol. 8, pp. 210, 213, 1914; Clark, Vol. 8, p. 419, 1915; Martin, Vol. 9, p. 253, 1916; Nomland, Vol. 10, p. 219, 1917; Weymouth, CaUf. Fish and Game Comm., Fish Bull. No. 4, p. 63, pi. 18, fig. 2, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 54, 1921; Yokoyama, Journ. Faculty Sci., Imp. Univ. Tokyo, Sect. II, Vol. 1, pt. 1, p. 2, 1925; pt. 4, p. 132, 1926; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 470, 1926; E. K. Jordan, Vol. 15, p. 245, 1926; Hanna and Hertlein, Vol. 16, p. 141, 1927. Panope estrellana Conrad, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916. Panope (generosa Gould var. ?) taniala n. sp. ? DaU, Nautilus, Vol. 32, p. 25, 1918. Panope abrupta Conrad, DaU, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 308, 1922. Panope generosum (Conrad), Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922. Type specimens: Of abrupta Conrad, 1849, in the U. S. National Museum, No. 3,608; of generosa, location unknown, probably in the U. S. National Museum; of estrellanus, in the U. S. National ^Museum, No. 13,320; of solida, globosa and toeniata, in the U. S. National Museum. Type localities: Of abrupta Conrad, 1849, Astoria, Oregon, Miocene; of generosa, Puget Sound, Recent; of estrellanus, Panza and Estrella Valleys, California, Miocene; of solida, San Francisco, California, Recent; of globosa, head of the Gulf of Cahfornia, Recent; of taniata, Magdalena Bay, Lower California, Mexico, Pleistocene or Recent ?. Miocene: Astoria, Oregon (Conrad, as ahrupla); Contra Costa County (Cooper); Estrella, San Luis Obispo County (Conrad, as extrcllanus); Foxin's, Santa Barbara County (Cooper); ? Vaqucros-Temblor; San Pablo formation of middle California; Santa Margarita formation north of Coalinga, and also near Santa Margarita, San Luis Obispo County (Nomland) ; lower Neocene (Clark) ; Bear River Miocene (questionably, Martin); etc. Pliocene: Jacalitos and Etchegoin formations near Coalinga (Arnold; Nomland); Etchegoin of Sargent oil field, near Sargent, Santa Clara County; Purisima and Merced formations south of San Francisco (Martin); Merced formation near Freestone, Sonoma County (Dickerson); lower Fernando of Els- mere and Holser canyons, Los Angeles County (English); Imperial formation of Coyote Mountain, Imperial County (Kew; Hanna) ; upper Pliocene at Santa Barbara (Cooper; Arnold) ; Loreto, Lower California, Mexico; Pliocene of Japan (Yokoyama); etc. Volume I ] PlIOCENE AND PLEISTOCENE MOLLTJSCA OF CALIFORNIA 425 Pleistocene: Santa Barbara to San Pedro (Cooper) ; "Pliocene" and lower San Pedro series of Deadman Island, rare (Arnold, 1903) ; "Saugus" formation, near Ventura (Waterfall) ; upper San Pedro series at Dead- man Island, San Pedro, and Los Cerritos (Arnold, 1903); ui)per Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan); Magdalena Bay, Lower California, Mexico, of Pleistocene or Recent age (Dall, as Is^niata, 1918); etc. Recent: Puget Sound to Scammons Lagoon, Lower California, Mexico (Jordan); also Gulf of California; Japan (Yokoyama). This well-known species lives in fine sand or mud where its very long, united siphons permit it to remain at a considerable depth. Being removed from many surface enemies and from the phj^sical shocks incident upon a more exposed habitat it has a shell which does not completelj^ cover its soft parts. As might be expected of a mud dweller, the shell varies considerably in shape, depending upon the nature of the medium in which it exists. Such variations can be seen in any large collection containing numerous specimens from different localities, and the extremes, when occurring directly with the normal form, may be regarded as abnormalities rather than as incipient species or even varieties. Nothing is gained and trouble is caused by cluttering up the literature with the names of freaks and pathologic individuals, hence such names are here treated as pure sjaionyms. These remarks apply to the so-called variety solida and to tceniata. The latter form was de- scribed from a single valve found on the beach, which it was suggested may have come from the Pleistocene beds whose fauna was the subject of the paper. It was unfigured and the description sounds like a subterfuge. Panope estrellana (Conrad) is generally supposed to be more elongate than P. generosa, but it does not appear significantly so. It probably came from Santa Margarita beds, upper Miocene in age. Conrad's figure is not unlike some specimens which would unquestionably be identified as generosa. In the Temblor horizon, lower middle Miocene, there is an elongate form of Panope which Wiedey has recently named P. tenuis.'^ The type specimen of this latter form is quite elongate and may represent a valid variety. The form from the Miocene of Astoria, Oregon, which Conrad named Mya abrupta is conspecific with generosa Gould. Conrad's name is preoccupied by his Pholadomya abrupta, which appears to belong to a subgenus of Panope. This latter species is charac- terized by having four or five radial ridges widely spaced over the medial portion of the valves. Portions of the shell are said to be perlaceous.- Deshayes and Milne Edwards' considered Conrad's Pholadomya a true Panope, but it may be subgenerically removed from the typical species. In a recent paper Dall and Ochsner described Panope sitnilaris* from deposits presumably of Pliocene age on Indefatigable Island, one of the Galapagos Group. It is similar in general aspect to generosa. Subgenus PANOMYA Gray, 1857 Panomya M. E. Gray, Fig. Moll. Anim., Vol. 5, p. 29, pi. 346, fig. 1, 18.57, only species, P. norvegica (Spengler); Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 832, 1898. Panopsea Menard de la Groye, H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 351, 1856, corrected to Panomya on ]). 659, 1858. Type (by monotypy), Mya norvegica Spengler, Acta Soc. Hist. Nat. Hafn., Vol. 3, p. 46, pi. 2, fig. 18, 1793, fide Dall, op. cit., p. 832, 1898, (not M. norwegica Gmelin, ' Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 154, loo, pi. 20. fig. 4. 1928. ' The shell of P. generosa is inclined to be earthy, but not so much so as that of Saxicava, and the extenor portion of the valves near the umbo is of a texture not far removed from pearly. This featxire is generally noticeable only in living specimens. • In Lamarck's Hist. Nat. Anim. s. Vert., Ed. 2, Vol. 6, p. 66, 1835. < Proc. Calif. Acad. Sci., Ser. 4. Vol. 17, p. 125, pi. 5, fig. 1, 1928. 426 San Diego Society of Natural History [Memoirs Syst. Nat., Ed. 13, Vol. 1, p. 3222, 1790); figured by M. E. Gray, op. cit., pi. 346, fig. 1, 1857. Shell smaller than that of Panope, s. .s., with a medial radial depressed area producing broad, rounded, radial bounding ridges or folds. There appears to be little difference in the shells of Panomya and Panope, s. s., aside from the smaller size and the medial radial depression of the former. Panope, s. s., is gener- ally proportionately more elongate and does not have the prominent radial folds which define the margins of the depressed portion of the valves of Panomya. The pallial sinus of Panomya generally appears as a succession of disconnected oval impressions. Panope (Panomya) arctica (Lamarck) Mya nmvegica Spengler, Acta Soc. Hist. Nat. Hafn., Vol. 3, p. 46, pi. 2, fig. 18, 1793, fide Dall, 1898; not of Chem- nitz nor Gmelin. Glycimeris arctica Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 458, 1818. Panopsea arctica Lamarck, Gould, Invert. Mass., p. 37, fig. 27, 1840. Panomya norvegica Spengler, Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 832, 833, 1898; Dall, in Mofiit, U. S. Geol. Surv., Bull. 533, p. 46, 1913. Pliocene: France and Italy; questionably in the Pliocene of Center Creek, Nome district, Alaska (Dall, 1898; in Moffit, 1913). Pleistocene: Pleistocene of the boreal north Atlantic and Pacific coasts (Dall, 1898). Recent: Arctic and boreal seas of both hemispheres, on the Pacific south to the Aleutians, and in the Atlantic in cold deep water to the Mediterranean (Dall, 1898). Spengler's work has not been available for reference. Gould's drawing of Panopoea arctica Lamarck illustrates a shell more strongly radially constricted than most specimens labelled P. ampla Dall in the Stanford collections. Dall (1898) has given a number of synonymic references not included above. Panope (Panomya) ampla (Dall) Plate 21, Figures 10a, 10b "Panopxa norvegica Spengler" Middendorff, Beitr. Malac. Rossica, Pt. 3, p. 78, pi. 20, fig. 11, 1849, in part, not of Spengler, fide Dall, 1898. Panomya ampla Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 833, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 183, 1903; Dall, Wash. Acad. Sci., Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 121, 1904, reissued by the Smithsonian Inst., 1910; Dall, in Moffit, U. S. Geol. Surv., Bull. 533, pp. 45, 46, 1913; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 590, 593, 1913; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 253, 1916; Moody, Vol. 10, p. 45, 1916; Dall, Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919, questionably; U. S. Nat. Mus., Bull. 112, p. 121, 1921; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 207, pi. 10, fig. 3, 1924. Panomya {ampla var. ?) chrysis Dall, U. S. Geol. Surv., Prof. Paper 59, p. 133, pi. 11, fig. 7, 1909. Shell ovate-subquadrate, rather heavy, gaping very widely in the rear, medial portions of valves depressed and bounded l)y radial folds; pallial sinus appearing as a series of irregular, often oval, impressions. Size (of normal Recent specimen from Departure Bay, British Columbia): Length, 62 mm.; height, 41 mm.; convexity of one valve, 11 mm. (left). Type specimens: Of ampla, in the U. S. National Museum, No. 151,221 (fide Old- royd); of chrysis. No. 154,093. Type localities: Of ampla, Aleutian Islands, Recent; of chrysis, Goldwasher's Gully, Coos Bay, Oregon, Miocene. Miocene: Empire formation of Coos Bay, Oregon (Dall, 1909, as var. chrysis; .\rnold and Hannibal ; Howe) Pliocene: Coos conglomerate, Coos Bay, Oregon (Howe); Merced and Purisima formations of San Francisco. (.Arnold; Martin); middle Wildcat formation of Humboldt County (Martin); Pliocene of Nome, Alaska (Dall, in MoflSt), and questionably of St. George Island, Pribilof Group (Dall, 1919); Fernando of Los .\ngeles (Moody). Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 427 Pleistocene: North Pacific, Bering, and Okhotsk seas (Dall) ; Douglas Island, Juneau Harbor, Alaska (Dall, 1904); "Pliocene" of Deadman Island, rare (Arnold). Recent: Arctic Ocean, Aleutian Islands, southeast to Puget Sound. "Panomya chrysis" Dall is not recognizably distinct from P. ampla Dall. This species is heavier shelled and more irregular in shape than the young of Panope (Panope) generosa Gould. Genus SAXICAVA Fleuriau de BeUevue, 1802 Hiatella F. M. Daudin, in L. A. G. Bosc, in Castel's new edit, of Hist. Nat. de Buffon, Coquilles, Vol. 3, p. 120, Paris (Deterville), 1802 (? 1801). Soxicova Fleuriau de BeUevue, Bull. Soc. Philom., No. 62, pp. 5, 10, 1802; Children, Quart. Journ. Sci., Lit., Arts, Vol. 14, p. 302, 1823; Gray, Proc. Zool. Soc. London for 1S47, p. 193, 1847; Herrmannsen, Indicis Gen. Malac, Vol. 2, p. 415, 1848; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 589, 1896; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 833, 1898. Agina Turton, Conch. Insul. Brit., Dithyra, p. 54, 1822, only species Mya purpurea. Type (by subsequent designation,' Children, 1823), Mytilus rugosus Linnaeus, 1767. Shell small, irregular, very inequilateral, the young with a cardinal tooth as in Panomya but the adult with the teeth obsolete; pallial line discontinuous. Animals burrowing in habit. Saxicava arctica (Linnaeus) Mya arctica Linnaeus, Syst. Nat., Ed. 12, p. 1113, 1767; Fabricius, Fauna Groenl., p. 407, 1780; Hanley, Ipsa Linn. Conch., p. 28, 1855. Solen minulus Linnaeus, Syst. Nat., Ed. 12, p. 1115, 1767; Chemnitz, Neues Syst. Conch. Cab, Vol. 6, p. 67, pi. 6, fig. 51, 1782; Montagu, Test. Brit., p. 53, pi. 1, fig. 4, 1803; Wood, Index Test., p. 16, pi. 3, Sole7i, fig. 33, 1825; Gen. Conch., p. 139, pi. 34, figs. 5, 6, 1835; Lamarck, Hist. Anim. s. Vert., Desh. Milne Edw. Ed., Vol. 6, p. 57, 1835. Cardita arctica Bruguiere, Encycl. Method., Vol. 1, p. 411, pi. 234, figs. 4a, 46, 1792. Hiatella monoptera Bosc, Hist. Nat. Coq., Vol. 3, p. 120, pi. 21, fig. 1, 1801 ;^de Bucquoy, Dautzenberg, and Dollfus, 1896. Didonta bicarinata Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 125, pi. 6, figs. 2a, 26, 1817. Hiatella arctica Linnaeus, Lamarck, Hist. .\nim. s. Vert., Vol. 6, p. 30, 1819. Saxicava arctica Linnaeus, Philippi, Enum. Moll. Sicil., Vol. 1, p. 20, pi. 3, figs. 3, 3a-d, 1836; Forbes and Hanley, Brit. Moll., Vol. 1, p. 141, Vol. 4, pi. 6, figs. 4-6, 1853; Sars, Moll. Reg. Arct. Norv., pp. 95, 96, pi. 20, figs. 8a-c, 1855; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 16, 1857; Sowerby, Thes. Conch., Vol. 5, p. 132, pi. 471, fig. 1, 1887; Dall, Proc. U. S. Nat. Mus., Vol. 12, p. 292, 1889; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, pp. 589-597, 1896; Dall, U. S. Geol. Surv., 17th .\nn. Rept., Pt. 1, p. 845, 1896; Trans. Wagner Inst. Sci., Vol. 3, pp. 834, 835, 1898; Wash. Acad. Sci., Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 121, 1904, reissued by the Smithsonian Inst., 1910; Lamy, Journ. Conchyl., Vol. 57, p. 248, 1909; Dautzenberg and Fischer, Res. Camp. Sci. Albert 1, Prince de Monaco, Fasc. 37, pp. 504-510, 1912; Dall, in Mofiit, U. S. Geol. Surv., Bull. 533, p. 46, 1913; Dall, Canadian Arctic Exped., Vol. 8, Pt. A, p. 29A, 1919; U. S. Nat. Mus., Bull. 112, p. 55, 1921 ; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 208, pi. 9, fig. 6, pi. 51, fig. 4, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925; E. K. Jordan, Proc, Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Saxicava ungaiui Grewingk, Russisch-Kaiserliche Mineralogische Gesellschaft zu St. Petersburg, Verhandlungen for the years 1848 and 1849, p. 354, pi. 6, figs. In-c, 1850; Dall, Wash. Acad. Sci., Alaska, Res. Harriman Alaska Exped., Vol. 4, p. 117, 1904, reissued by the Smithsonian Inst., 1910. Saxicava insita Conrad, Amer. Journ. Conch., Vol. 5, p. 40, 1869. Miocene: St. Paul Island, Nushagak, Atka Island, Morshowi, Pavloff Bay, Unga Island, Kadiak Island, Alaska (Dall, 1896, 1904); Unga, Alaska (Grewingk, Tertiary, as Ann. Mag. Nat. Hist., Ser. 2, Vol. 8, pp. 3S0-3S6, 1851. s Proc. Acad. Nat. Sci. Phila., Vol. 14, pp. 191-221, 1862. ' Man. Conchyl., pp. 1130-1137. 1887. < Trans. Wagner Inst. Sci., Vol. 3, pp. 814-821, 1898. Volume I 1 PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 431 Roussillon, Vol. 2, pp. 609-615, pi. 87, figs. 1-5, 1896; Atlantic from England to Gibraltar and the Mediterranean, Recent; also European Pliocene and Pleistocene. Shell equivalve, elongate-cj'lindric, generally gaping somewhat anteriorly and never closed by a callum ; sculpture of radial spinose lamellae, accentuated on the anterior portion of the shell ; posterior margm of valves without cyathiform appendix; styloid apophysis large, concave; with one or more accessory plates, or all plates obsolete. Subgenus PHOLAS, s. s. Shell gaping anteriorly; dorsal region with two protoplaxes. The typical subgenus does not appear to be represented in the California region. Subgenus BARNEA Risso, 1826 Barnea Leach MS., Risso, Hist. Nat. Eur. Merid., Vol. 4, p. 376, 1826, only species, B. sirinosa Risso, unfigured; Tryon, Proc. Acad. Nat. Sci. Pliila., Vol. 14, pp. 194, 207, 1862; Fischer, Man. Conchyl., p. 1133, 1887; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 615, 1896; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 815, 1898. Barnia Leach MS., Gray, Synop. Cont. Brit. Mus., Ed. 44, p. 76, 1842, fide Sherborn. Holopholas Fischer, Man. Conchyl., p. 1133, 1887. Type (by monotypy), Barnea spinosa Risso, op. cit., p. 376, 1826, = Pholas candidus Linnseus, Syst. Nat., Ed. 10, p. 669, 1758; figured in Reeve, Conch. Icon., Vol. 18, PhoJas, pi. 1, fig. 1, 1872; also figured and discussed by Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, pp. 615-620, pi. 88, figs. 1-7, 1896; Atlantic, Mediterranean, etc. Shell not gaping in front; sometimes with only one accessory plate, a lanceolate protoplax, sometimes with a transverse mesoplax also. Barnea has a very small gape or entirely lacks the anterior gape of typical Pholas. Section Barnea, s. s. With one accessory plate, a lanceolate protoplax. Section Scobinopholas, new name Scobina Bayle, Journ. Conchyl,, Vol. 28, p. 242, 1880, new name for Pholas Linnaeus of H. & A. Adams, type, Pholas coslala Linnseus; not Scobina Lepeletier, Encycl. M^th., Insecta, Vol. 10, p. 574, 1825, Hymenoptera. Type: Pholas costatus Linnseus. With two accessory plates, a lanceolate protoplax and a transverse mesoplax. As Scobina was used for a group of insects many years before its application to mol- lusks, we have substituted Scobiyio pholas as a new name with Pholas costatus as type. This group is the typical Pholas of Lamarck, 1801,' but not 1799. Pholas (Barnea) costatus Linnaeus Pholas costatus Linnseus, Syst. Nat., Ed. 10, p. 669, 17.58, Wood, Gen. Conch., pi. 15, figs. 1, 2, 1815; Lamarck, Hist. Anim. s. Vert., Vol. 5, p. 445, 1818; Ed. 2, Vol. 6, p. 45, 1835; Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 14, p. 201, 1862; Reeve, Conch. Icon., Vol. 18, Pholas, pi. 1, figs. 2a, 2b, 1872. Pholas virginianus Lister, Hist. Conch., Ed. 2, pi. 5, fig. 434, 1770. Barnea {Scobina) costata Linnaeus, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 816, 1898. Barnea costata Linnaius, Dall, U. S. Nat. Mus., Bull. 37, p. 72, pi. 68, fig. 9, 1889; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 462, pi. 28, figs. 5, 6, 1926. ' Syst. Anim. s. Vert., p. 127, only example given Pholas costatus Linnseus. In the Prodrome, 1799, Lamarck gave P. dactylus as example. 432 San Diego Society of Natural History [ Memoirs Pliocene: Coyote Mountain, western Imperial County, California (Hanna); Caloosahatchie marls, Florida (Dall). Pleistocene: Massachusetts, Maryland, South Carolina, Florida (Dall). Recent: Massachusetts south to Mexico and Brazil (Dall). Subgenus ZIRTAEA Gray, 1842 Zirfsea Gray, Synop. Cont. Brit. Mus., Ed. 42, p. 150, 1840, nomen nudum, fide Iredale, Proc. Malac. Soc. London, Vol. 10, p. 298, 1913; Synop. Cont. Brit. Mus., Ed. 44, p. 76, 1842; diagnosis, no species, fide Iredale; Proc. Zool. Soc. London for 1847, p. 188, 1847, type designated, "Ph. crispata;" Ann. Mag. Nat. Hist., Ser. 2, Vol. 8, pp. 381, 385, 1851, generic name attributed to "Leach MSS."; Fischer, Man. Conchyl., p. 1133, 1887; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 817, 1898. Zirphxa Leach, Mollusc. Brit. Synop., pp. 250, 252, 1852; Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 14, pp. 194, 210, 1862. Type (by subsequent designation, Gray, 1847), Pholas crispatus Linnaeus. Shell with a large anterior gape; accessory plates rudimentary or wanting; a radial sulcus di- viding each of the valves into two areas. The shells of this subgenus are oval in shape and have a large anterior gape which is quite conspicuous. Pholas (Zirfaea) crispatus (Linnaeus) Mya crispata Linnaeus, Syst. Nat., Ed. 10, p. 670, 1758. Pholas crispata Linnseus, Syst. Nat., Ed. 12, p. IlII, 1767; Reeve, Conch. Icon., Vol. IS, Pholas, pi. 3, fig. 9, 1872. Pholas bifrons Da Costa, Brit. Conch., p. 242, pi. 16, fig. 4, 1778. Pholas parva Da Costa, op. cil., p. 247, 1778, young. Solen crispus Gmelin, Syst. Nat., Ed. 13, p. 3228, 1791. Zirfa?a crispata Linnaeus, Gray, Ann. Mag. Nat. Hist., Ser. 2, Vol. 8, p. 385, 1851; Dall, U. S. Nat. Mus., Bull. 37, p. 72, pi. 68, fig. 10, 1889; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 817, 818, 1898. Zirphsea crispata Linnaeus, Leach, Mollusc. Brit. Synop., p. 252, 1852; Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 14, p. 211, 1862. Pliocene: Atlantic coast Pliocene (Dall). Pleistocene: Labrador and boreal eastern America (Dall, 1898). Recent: South Carolina to Arctic Ocean; also eastern Atlantic coast. This species occurs on the Atlantic coast of North America from the Pliocene to the Recent, and is living from South Carolina to the Arctic. However, there is as yet no authentic report of its occurrence on the Pacific coast. Carpenter, Nomland, and others who listed it probably had gahhi (Tryon) or Pholadidea ovoidea (Gould). Pholas (Zirfcea) crispatus Linnaeus is much shorter and higher than gabbi of the Pacific coast. Pholas (Zirfaea) gabbi (Tryon) Plate 24, Figure 2 Zirfsa gabbi Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 15, p. 144, pi. 1, fig. 1, 1863, Zirphsea; Tryon, Amer. Journ. Conch., Vol. 3, Pt. 3, Appendix p. 6, 1868; Cooper, 7th Ann. Rept. Cahf. State Mineralogist, p. 270, 1888, Zirphxa; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 184, 1903, Zirphsea; Dall, U. S. Nat. Mus., Bull. 112, p. 55, 1921; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 63, pi. 18, fig. 1, 1920; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 210, pi. 36, fig. 1, 1924; E. K. Jordan, Proc. Cahf. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929, Zirpha:a. "Zirphsea crispata Linnaeus," Carpenter and others, not of Linnaeus. Not "Zirphsea gabhii Tryon," Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, pp. 52, 53, pi. 15, fig. 10, 1868-9, = Pholadidea ovoidea (Gould). ? "Zirphsea aff. crispata (Linnc)," Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 301, 1917. Type specimen: In the Academy of Natural Sciences of Philadelphia. Type locality: California or Japan, Recent, fide Tryon and Gabb. Volume I] PlIOCENE AND PLEISTOCENE MoLLITSCA OF CALIFORNIA 433 ? Miocene: Alameda County (Cooper) ; ? Santa Margarita formation, upper Miocene, north of Coalinga (Nom- land). Pliocene: Middle Etchegoin, middle Pliocene of the General Petroleum Corporation well, Stiles No. 1, near McFarland, Kern County, depth 3900-18 feet (H. R. Gale) ; "Pico" near Ventura (Waterfall). Pleistocene: "Quite rare in the upper San Pedro series at San Pedro, Los Cerritos, Crawfish George's, and Deadman Island" (Arnold); Pleistocene of San Quintin Bay, Lower California, Mexico (Orcutt). Recent: Bering Sea and islands and south to San Diego, California; also Japan (Oldroyd). This species is closely allied to crispatus, but is proportionately much longer. Gabb's figure of gabbi represents Pholadidea ovoidea (Gould), which is a short stumpy form with a calcareous callum that may be broken away leaving a large, open anterior gape. Pholas (Zirfaea) dentatus (Gabb) Zirphga dentata Gabb, Geol. Surv. Calif., Palieo., Vol. 2, p. IS, 1866, pi. 3, figs. 31, 31a, 1868-9; Arnold, U. S. Geol. Surv., Bull. 396, pp. 17, 21, 25, 26, 27, pi. 7, fig. 5, 1910; Bull. 398, pi. 29, fig. .5, 1910; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 421, pi. 63, figs. 1, 2, 191.5. Type locality: East end of Kirker's Pass, Contra Costa County; possibly Miocene. Miocene: Vaqueros formation (including the Temblor), lower Miocene of middle California (Arnold); upper and lower San Pablo, upper Miocene of middle California (Clark). Pliocene: Jacalitos formation of Coalinga region, lower Pliocene (Arnold). According to Gabb, "This shell is closely allied to Z. crispata but differs in its more regularly cylindrical form, the marked reflection of the posterior dorsal margin, and the angular dentated dorsal plate." Subfamily Martesiinae Anterior gape or hiatus closed in the adult by a callum. The subfamily name Jouannetinoe Tryon is based upon Jouannetia,^ which dates from 1828. We have substituted Martesiince, based upon Martesia, which dates from 1824. However, the subfamily distinctions are artificial, and may not be of value. Genus PHOLADIDEA Goodall in Turton, 1819 Pholadidea Goodall, Turton, Conch. Diet., p. 147, 1819; Gray, Proc. Zool. Soc. London for 1847, p. 188, 1847, type Phol. papyracea; Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 14, pp. 194, 212, 1862; Fischer, Man. Conchyl., pp. 1133, 1134, 1887; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 818, 1898. Pholidsea Leach, Swainson, Treat. Malac, p. 364, only species, P. papyracea. Pholadidsea Turton, Gray, Ann. Mag. Nat. Hist., Ser. 2, Vol. 8, 1851. Type (by monotypy), Pholadidea loscombiana Goodall, = Pholas papyraceus Turton, Conch. Insul. Brit., Dith., p. 2, pi. 1, figs. 1-4, 1822, also figured by Jeffreys, Brit. Conch., Vol. 3, p. 116, pi. 4, fig. 2, 1865, Vol. 5, p. 193, pi. 53, figs. 2, 3, 1869; coasts of England, France, etc. Shell with a double or single protoplax and with or without other accessory plates, the valves prolonged posteriorly into leathery or testaceous cups or a tube (siphonoplax) protecting the siphons. Subgenus PHOLADIDEA, s. s. With a double, rather small protoplax, a cup-like siphonoplax ajid generally without other acces- sory plates; a single radial sulcus present. The section Penitella Valenciennes (in Du Petit-Thouars, Voy. Venus, Atlas Moll., pi. 24, 1846) differs from the typical section of Pholadidea in that a small mesoplax is present and the two parts of the protoplax are confluent. The type is P. conradi Valen- ciennes, which is a synonym of P. penita Conrad. ' Des Moulins, Bull. Hist. Nat. Soc. Linn^enne de Bordeaux. Vol. 2, p. 244, 1828, monotype, J. semicaudata Des Moulins, Miocene of France. 434 San Diego Society of Natural History [ Memoirs Pholadidea (Pholadidea) penita (Conrad) Plate 24, Figures la, 16 Pholas penita Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 237, pi. 18, fig. 7, 1837. ? Pholas concameraia Deshayes, Guerin's Mag. Zool., 1840, pi. 17, fide Tryon, 1862; Sowerby, Thes. Conch., Vol. 2, p. 497, pi. 106, figs. 67, 68, 1849. Penitella eonradi Valenciennes, Voy. Venus, Atlas Moll., pi. 24, fig. 1, 1846; Conrad, Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 2, p. 335, 1854. Penitella penita Conrad, Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 14, p. 215, 1862; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 88, 1868-9. Pholadidea penita Conrad, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 637, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 259, 1888; Keep, West Coast Shells, p. 212, fig. 181, 1888, 1892; Dall, U. S. Geol. Surv., Prof, Paper 59, p. 134, 1909; Packard, Univ. Calif, Publ. Zool., Vol. 14, p. 288, pi. 30, figs. 3a, 3b, 1918; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 64, pi. 19, fig. 2, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 55, 1921; I. S. Oldroyd, Stanford, Univ. Publ. Geol., Vol. 1, p. 211, pi. 21, fig. 10, pi. 51, figs. 3a, 36, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925. Pholadidea (Penitella) penita Conrad, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 184, 1903. ? Pholadidea penita concameraia Deshayes, Dall, U. S. Nat. Mus., Bull. 112, p. 55, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 211, pi. 22, figs. 4, 5, 1924. Type specimens: Of penita, possibly in the Academy of Natural Sciences of Phila- delphia; of concameraia, in the British Museum. Type localities: Of penita, near San Diego or Santa Barbara, California, Recent; of concameraia, Monterey, California, Recent. Miocene: Empire formation of Coos Bay, Oregon (Dall, 1909). Pliocene: Santa Barbara (Gabb; Cooper). Pleistocene: Lower San Pedro of Nob Hill cut, San Pedro, plentiful (T. S. Oldroyd); upper Pleistocene south- west of Goleta (coll. by Grant) ; upper San Pedro series of San Pedro, Los Cerritos, Crawfish George's and Deadman Island (Arnold). Recent: Chirikoff Islands, Alaska, to San Diego, California (Dall, 1921). This species is close to P. ovoidea (Gould), which is shorter, more ovoid, and has a vacant space between the umbonal plate and the umbo. In penita the plate is closely appressed to the umbo. P. concameraia (Deshayes) has recently been considered a valid variety. Gabb's report of an occurrence in the Post-Pliocene of Santa Barbara may refer to the late Pleistocene deposits near the coast several miles west of the town. Well- preserved specimens occur in the terrace deposit a few miles southwest of Goleta (locality 74). Pholadidea penita (Conrad) is the type of Penitella Valenciennes, a section which may be disregarded. Pholadidea (Pholadidea) ovoidea (Gould) Pholas ovoidea Gould, Proc. Boston Soc. Nat. Hist., Vol. 4, p. 87, 1851; Boston Journ. Nat. Hist., Vol. 6, p. 388, 1853; Reeve, Conch. Icon., Vol. 18, Pholas, pi. 12, figs. 49a, 496, 1872. Penitella spelxa Conrad, U. S. Pac. R. R. Repts., Vol. 5, p. 326, pi. 5, figs, 43, 43a, 436, 1858. Pholadidea ovoidea Gould, Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 14, p. 213, 1862; Arnold, Smithsonian Misc. Coll., Vol. 50, p. 444, pi. 55, figs, la, 16, 1907; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 288, pi. 30, figs, la, 16, 2a, 26, 1918; Dall, U. S. Nat, Mus., Bull, 112, p. 56, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 212, pi. 21, figs. 5, 6, pi. 51, figs, la, 16, 2a, 26, 1924. ? Zirphxa crispata Linnaeus, Carpenter, Brit. Assn. Adv. Sci., Rept, for 1863, pp. 602, 611, 637, 682, 1864; Nomland, Univ. Calif. Publ. Geol., Vol, 10, p, 230, 1917. "Zirpha'tt gahhii Tryon," Gabb, Geol. Surv. Calif., Palso., Vol. 2, p, 52, pi, 15, fig, 10, 1868-9, not of Tryon. Type locality: Monterey, California; Recent. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 435 ? Pliocene: Middle Etchegoin of the Coalinga region, middle Pliocene (Nomland, as Zirphsea crispata). Pleistocene: San Pedro (Gabb, as Z. gabbii). Recent: Bering Sea to Gulf of California (Dall). The very short ovoid form serves to characterize this species. It is amply figured in the publications of Gould, Reeve, and Oldroyd. Subgenus PARAPHOLAS Conrad, 1849 Parapholas Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 4, p. 121, 1849; Journal Acad. Nat. Sci., Phila., Ser. 2, Vol. 1, pt. 3, p. 214, August, 1849; pt. 4, p. 279, January, 1850; Vol. 2, p. 335, 1854; Tryon, Proc. Acad. Nat. Sci. Phila., Vol. 14, pp. 194, 212, 1862, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 819, 1898. Type (bj^ monotypy), Pholas californicus Conrad. With one large protoplax; mesoplax and metaplax present, double but not confluent; double hypoplax present; valves with two radial sulci, the posterior sometimes obsolete; siphonal appendix thin, horny, not attached to a calcareous tube formed in the burrow of the animal. Pholadidea (Parapholas) califomica (Conrad) Pholas californica Conrad, Journ. Acad. Nat. Sci. Phila., Ser. 1, Vol. 7, p. 236, pi. 18, fig. 5, 1837; Ser. 2, Vol. 2, p. 335, 1854. I Pholas janelli Deshayes, Proc. Zool. Soc. London for 1839, p. 357. j Parapholas californica Conrad, Proc. Acad. Nat. Sci. Phila., for 1848, p. 121; Tryon, Vol. 14, p. 214, 1862; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 590, 1913; Weymouth, Calif. Fish and Game Comm., Fish Bull. No. 4, p. 64, pi. 19, fig. 1, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. .55, 1921; Howe, Univ. Calif. I Publ. Geol., Vol. 14, p. 92, 1922; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 210, pi. 22, figs. 7, 13, I pi. 36, figs. 2a, 26, 1924. Type locality: San Diego or Santa Barbara, California; Recent. Miocene: Empire formation of Coos Bay, Oregon (Arnold and Hannibal). Pliocene: Coos conglomerate, Coos Bay, Oregon (Howe). Recent: Monterey to San Diego, California (Dall, 1921). 436 San Diego Society of Natural History [ Memoirs CLASS SCAPHOPODA ORDER SOLENOCONCHA Family DENTALIIDAE Shell greatest in diameter at the oral opening. Width of the median tooth of the radula double its height; foot with an encircling epipodial sheath which is discontinuous, interrupted on the side next to the head. (Pilsbry and Sharp, 1897.) Genus DENTALIUM Linnaeus, 1758 Dentalium LinnEeus, Syst. Nat., Ed. 10, p. 785, 1758; Montfort, Conch. Syst., Vol. 2, p. 23, 1810; Children, Quart. Journ. Sci., Lit., Arts, p. 69, October, 1822; Pilsbry and Sharp, Tryon's Man. Conch., Ser. 1, Vol. 17, p. x.xix, 1897; Henderson, U. S. Nat. Mus., Bull. Ill, p. 8, 1920. Type (by subsequent designation, Montfort, 1810), Dentalium elephantinum Lin- naeus, figured by Pilsbry and Sharp, op. cit., p. 1, pi. 1, figs. 1-7, 1897; Amboyna; Philip- pine Islands; Recent. Shell an elongate tube varymg from strongly curved to almost straight, open at both ends, and with the maximum diameter at the oral opening; sculptured with longitudinal ribs, which may be faint or strongly developed. Dentalium neohexagonum Sharp and Pilsbry "Dentalium hexagonum Sowerby," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 612, 648, 1864; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 86, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 238, 1888 Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 194, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 185, 1903 not Dentalium hexagonum Gould, Proc. Boston Soc. Nat. Hist., Vol. 7, p. 166, Dec, 1859, Japan, China, etc Dentalium neohexagonum Sharp and Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 17, p. 19, pi. 11, figs. 74-86, 1897 Pilsbry, Nautilus, Vol. 17, p. 108, 1904; Dall, U. S. Nat. Mus., Bull. 112, p. 57, 1921; E. K. Jordan, Bull So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925 E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 9, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. "Dentalium pseudohexagonum Dall," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 186, pi. S, figs. 12, 12a, 1903. Shell slender, attenuated and strongly curved toward the apex; sculpture of six strong, pro- jeetmg ribs, which are much reduced on the larger third of the shell, intercalary riblets low or absent; aperture rounded, hexagonal; anal orifice without notch or slit. Pliocene: Balboa Park and Pacific Beach, San Diego (Arnold); San Diego well (Cooper). Pleistocene: Upper and lower San Pedro series of the San Pedro region (Arnold); Barlow's Ranch, near Ven- tura (Arnold) ; "Saugus" near Ventura (Waterfall) ; lower San Pedro of Nob Hill cut (T. S. Oldroyd) ; at Twenty-sixth Street and at Spanish Bight, San Diego (Arnold); lower Quaternary at Madgalena Bay, and upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Guacomayo, Central America (Dall, 1921). The present writers have not seen the true hexagonum and do not know whether neohexagonum is well distinguished or not. Dentalium semistriatum Turton variety semipolitum Broderip and Sowerby Dentalium semipolitum Broderip and Sowerby, Zool. Journ., Vol. 4, p. 369, 1829; ? Sowerby, Thes. Conch., Vol. 3, p. 100, pi. 224, fig. 23, 1860; in Reeve's Conch. Icon., Vol. 18, Dentalium, pi. 4, fig. 19, 1872; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 238, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 187, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 57, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 10, 1927. Dentnliiim hyalinum Philippi, Zeitschr. f. Malak., Vol. 3, p. 55, 1846, not of Carpenter, 1855-7, fide Pilsbry and Sharp, 1897. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 437 Dentalium liratum Carpenter, Cat. Reigeti Coll. Mazatlan Moll. Brit. Mus., p. 188, 1855-7, young shell, fide Pilsbry and Sharp, 1897. Dentalium Urulatum Morch, Malak. Blatter, Vol. 7, p. 177, 1861, ^We Pilsbry and Sharp, 1897. Dentalium semistrialuni Turton, variety scmipolitum Broderip and Sowerby, Pilsbry and Sharj), Tryon's Man. Conch., Ser. 1, Vol. 17, pp. 90, 91, pi. 16, fig. 54, 1897. Pliocene: San Diego well, San Diego (Dall). Pleistocene: "Rare in upper San Pedro series at San Pedro, Deadman Island, and Crawfish George's," Los Angeles County (Arnold) ; upper Pleistocene at San Quintin Bay, Lower California, Me.xico (Jordan). Recent: San Pedro, California, to Mazatlan, Mexico (Dall, 1921). This slender shell is marked with very numerous, fine, closely-set, subequal, longi- tudinal strise, extending from the apex downward, about two-thirds of the length of the shell, the remaining surface being smooth. There is no notch or slit on the minute, round anal orifice. According to Pilsbry and Sharp, Dentalium semistriatum Turton,^ of the Gulf of Mexico, is not specifically different; and it is probable that semipoUtum should be considered a synonym. Dentalium pretiosum Nuttall in Sowerby "Dentalium politum Lamarck," Middendorff, not Lamarck. Dentalium yreliosmn Nutt., Sowerby, Thes. Conch., Vol. 3, p. 95, pi. 225, fig. 57, 1860; Keep, West Coast Shells, p. 113, fig. 101, 1888, 1892; Pilsbry and Sharp, Tryon's Man. Conch., Ser. 1, Vol. 17, p. 44, pi. 13, figs. 1, 2, 3, 1897; Dall, U. S. Nat. Mus., Bull. 112, p. 57, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 8, 1925; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 1, p. 13, pi. 1, fig. 10, 1927. Dentalium (var.) indianorum, Dentalium (? pretiosum Nutt., Sby. var.) indianorum, Dentalium indianorum, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, pp. 612, 648, 683, 1864. Dentalium indianorum Carpenter, Cooper, 7th Ami. Rept. Calif. State Mineralogist, p. 238, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 186, pi. 8, fig. 4, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908. Dentalium cf. pretiosum Sowerby, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pliocene: "Pico" near Ventura (Waterfall, as "Dentalium cf. pretiosum Sowerby"); upper Pliocene at Bath- house Beach, Santa Barbara (Berry). Pleistocene: Lower San Pedro series of San Pedro and Deadman Island (Arnold) ; lower San Pedro of Nob Hill cut, San Pedro (T. S. Oldroyd); Santa Barbara (Cooper); "Saugus" near Ventura (Waterfall, as "Dentalium cf. pretiosum Sowerby"); rare in the upper San Pedro at Crawfish George's, San Pedro (Arnold); upper Quaternary at San Ignacio Lagoon, Lower California, Me.xico (Jordan). Recent: Forrester Island, Alaska, to Cedros Island, Lower California, Mexico. This species lacks longitudinal sculpture, except for strise near the apex or on young specimens. The orifice at the apex is oblong and extends into a small notch on the convex side. This species is very similar to Dentalium entalis stimpsoni Henderson, = and belongs to the section Antalis H. and A. Adams. Dentalium rectius Carpenter Dentalium. rectius Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 603, 648, 1864; Proc. Acad. Nat. Sci. Phila. for 1865, p. .59; Newcombe, Nautilus, Vol. 10, p. 18, 1896; Pilsbry and Sharp, Tryon's Man. Conch., Ser. 1, Vol. 17, p. 114, pi. 21, fig. 45, 1897; Dall, U. S. Nat. Mus., Bull. 112, p. 57, 1921; Howe, Univ. Calif. Publ. GeoL, Vol. 14, p. 94, 1922; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 11, pi. 1, fig. 3, 1927. ? Dentalium petricola Dall, U. S. Geol. Surv., Prof. Paper 59, p. 136, 1909, fide Howe, 1922. ? Miocene: Miocene of Astoria (Dall, 1909, fiAe Howe, 1922). Pliocene: Coos conglomerate of Coos Bay, Oregon, and upper WUdcat formation of Humboldt County, Cali- fornia (Howe). Recent: Stephens Passage, Alaska, to Panama Bay (Dall, 1921). 1 Conch. Diet. Brit. Is., p. 39, pi. 18, fig. 68, 1819. 2 U. S. Nat. Mus., Bull. Ill, p. 35, pi. 4, figs. 2. 3, 4. 1920. 438 San Diego Society of Natural History [ Memoirs This is a long, slender, nearly straight, fragile shell, with a smooth, glossy surface and no notch on the orifice at the slender apical end. It is smaller and less curved than D. dalli Sharp and Pilsbrj^, but is larger and less slender than D. ivatsoni Sharp and Pilsbry. It is the type of the section Rhabdus Pilsbry and Sharp, 1897, by original designation. Family CADULIDAE (SIPHONODENTALIIDAE) Shell generally smooth, often inflated; width of median tooth much less than double its length, generally less than the length; foot veneriform, capable of expansion mto a terminal or subterminal rosette-like disk, not interrupted dorsally. (Pilsbry and Sharp, 1897.) This family, generally called SiphonodentaUidcp, includes the genera CaduJus, Siphon- odentalium, and Entalina. For a discussion of the systematics of these genera the reader is referred to the monograph by Pilsbry and Sharp in Tryon's Manual of Conchology (Series 1, Volume 17) and to a recent monograph on the east American Scaphopoda by Henderson (U. S. National Mu.seum, Bulletin 111, 1920), both of which have been used in the arrangement given below. Genus CADULUS Philippi, 1844 Cadulus Philippi, Enum. Moll. SicU., Vol. 2, p. 209, 1844; Herrmannsen, Indicis Gen. Make, Vol. 1, p. 150, 1846; Pilsbry and Sharp, Tryon's Man. Conch., Ser. 1, Vol. 17, pp. 131, 142, 1897; Henderson, U. S. Nat. Mus., Bull. HI, p. 11, 1920. Type (by subsequent designation, Herrmannsen, 1846),' Cadulus ovulum Philippi, op. cit, Vol. 2, p. 208, pi. 27, fig. 21, 1844, fide Pilsbry and Sharp, op. cit., p. 157, pi. 32, figs. 40, 41, 1897. Shell more or less swollen near the middle, smooth, polished, circular or oval m cross section, apex simple or with two to four notches or slits. The genera Entalina Monterosato, 1872, and Siphonodentalium M. Sars, 1859, con- tain the members of the CaduUdce which have the shell largest at the aperture. Entalina further differs from Cadulus in being longitudinally ribbed. The genus Cadulus can be somewhat artificially subdivided into sections as follows: Apex not slit or notched : Small obese forms, dorsal and ventral arcs both convex Cadulus, s. s. Slender forms, one arc convex, the other more or less concave. .Gadilia Gray- Apex with two prominent slits Dischides Jeffreys' Apex with four prominent slits, leaving four prominent, triangular lobes .■ • • ■ Polyschides Pilsbry and Sharp* Apex with four very shallow notches, leaving four wide lobes . Platyschides Henderson^ ^ Philippi's original description of Cadulus has not been available. 2 Proc. Zool. Soc. London for 1847, p. 159, type D. gadus, by original designation. » Ann. Mag. Nat. Hist., Ser. 3, Vol. 20, p. 251, 1867, type Cadulus polilus S. V. Wood. * Tryon's Man. Conch., Ser. 1, Vol. 17, p. 146. 1897, type, by original designation, Cadulus {Polyschides) tetraschislus Watson, Journ. Linn. Soc. London, Vol. 14, p. 521, 1879. 6 U. S. Nat. Mus., Bull. Ill, p. 104, 1920, type, by original designation, Cadulus arandis Verrill, Trans. Conn. Acid. Arts Sci., Vol. 6, p. 219, pi. 44, fig. 20, 1884. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 439 Cadulus fusifonnis Pilsbry and Sharp "Cadulus fusiformis Philippi," Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 231, 1888. Cadulus fusifnrmis Pilsbry and Sharp, Tryon's Man. Conch., Ser. 1, Vol. 17, p. 19.3, pi. 35, fig. 14, 1897; Pilsbry, Nautilus, Vol. 17, p. 108, 1904; Dall, V. S. Nat. Mus., Bull. 112, p. 58, 1921; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 1, p. 15, pi. 1, fig. 4, 1927. Pliocene: San Diego well, San Diego (Cooper). Recent: Monterey, California, to Cape San Lucas, Lower California, Mexico (Dall). This species is only slightly curved and the shell is not much contracted beyond the point of greatest inflation. The apex is simple, rather sharp lipped. "Cadulus nitentior Carpenter" of Arnold (Mem. Calif. Acad. Sci., Vol. 3, p. 187, pi. 8, fig. 15, 1903) is probably a serpuloid annehd, according to Pilsbry (1904). The "Cadulus fusifonnis Philippi" of Cooper, from the middle Pliocene of the San Diego well, is the present species; but it was a nomen nudum until described by Pilsbry and Sharp. Cadulus hepbumi Dall Cadulus hepbumi Dall, Bull. Nat. Hist. Soc. Brit. Columbia, No. 2, p. 12, pi. 1, fig. 13, 1897; Pilsbry and Sharp, Tryon's Man. Conch., Ser. 1, Vol. 17, p. 194, pi. 35, figs. 19, 20, 1897; Dall, U. S. Nat. Mus., Bull. 112, p. 58, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 15, pi. 1, fig. 13, 1927. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd). Recent: Victoria, British Columbia, to Monterey, California (Dall, 1921). This shell is very close to C. fusiformis, but is more curved and more constricted at the aperture. Cadulus tolmiei Dall Cadulus tolmiei Dall, Bull. Nat. Hist. Soc. Brit. Columbia, No. 2, p. 13, pi. 1, fig. 8, 1897; Pilsbry and Sharp, Tryon's Man. Conch., Ser. 1, Vol. 17, p. 181, pi. 34, figs. 3, 4, 1897; DaU, U. S. Nat. Mus., Bull. 112, p. 58, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 16, pi. 1, fig. 9, 1927. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Vancouver Island, British Columbia, to San Quintin Bay, Lower California, Mexico (Dall, 1921). This small species is much like Cadulus rushi Pilsbry and Sharp, of the Atlantic coast. Cadulus arcticus Dall Cadulus arcticus Dall, U. S. Geol. Surv., Prof. Paper 125-C, p. 30, pi. 5, fig. 8, 1920. Pliocene: "Pliocene of Carter Creek, in the Camden Bay region of the Arctic coast, 1 mile from the coast" (DaU). 440 San Diego Society of Natural History [Memoirs CLASS GASTROPODA ORDER PTEROPODA The pteropods are naked or thin-shelled pelagic mollusks that swim actively by means of fin or wing-like appendages modified from the foot. Species that are protected by a thin, transparent or translucent shell have been placed in the suborder Thecosornata, the naked forms being grouped under the Gymnosotnata. Some of the thick-shelled, elongate, tapering, tubular species of the Paleozoic (the Conulariidce) may not be closely related to the more modern Pteropoda. Family CLIIDAE Shell bilaterally symmetrical, thin, glassy, ventricose, shield shaped, pyramidal, or conically tubiform. Geologic range: Cretaceous to Recent. As Clio is the oldest genus in the family, we have used the name Cliidce in preference to Cavolinidoe. Genus CAVOLINA Abilgaard, 1791 Cavolina Abilgaard, Skrivter af Naturhistorie-Selskabet, Vol. 1, Heft 2, p. 174, 1791 ; Sykes, Proc. Malac. Soc. London, Vol. 7, p. 5, 1906; DaU, Bull. Mus. Comp. Zool., Harvard College, Vol. 43, no. 6, p. 230, 1908; Suter, Man. New Zealand Moll., p. 53, 1913; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 112, 1928. Not Cavolina Bruguiere, Ency. M6th., Vers, pi. 85, 1791, a nudibranch. Hyalsea Lamarck, "Prodr.," M6m. Soc. Hist. Nat., Paris, SOr. 1, Vol. 1, p. 89, 1799. Type (by monotypy), Cavolina natans Abilgaard = Monoculus ielemus Linnseus. Shell globose, composed of two unequally arched pieces, one of which projects helmet-like ante- riorly beyond the other, is less convex, and is marked by a few radial grooves or undulations, both pieces coming to a posterior point, often with sharp angles or cusps laterally, which with the central point give the posterior end a tricuspid appearance. Geologic range: Miocene to Recent. Geographic distribution: Widespread, pelagic. Cavolina telemus (Liimseus) Monoculus telemns Linnseus, Syst. Nat., Ed. 10, p. 635, 1758. Anomia tridentata Forskal, Descriptiones Animalium Quae in Itinere Orientali Observavit, p. 124, 1773. Cavolina natans Abilgaard, Skriv. Naturhist.-Selsk., Vol. 1, Heft 2, p. 175, pi. 10, 1791. Hyalxa tridentata Lamarck, Blainville, Man. Malac, p. 480, pi. 46, fig. 2, 1825; Sowerby, Conch. Man., Ed. 1, p. 52, fig. 226, 1839; Ed. 2, p. 164, fig. 226, 1842; Ed. 3, same p. and fig., 1846; Ed. 4, p. 172, pi. 11, fig. 198, 1852; Rang and Souleyet, Hist. Nat. Moll. Pt^ropod^e, pp. 35-37, pi. 2, figs. 1-6, pi. 12, figs. 1-4, 1852; Boas, Spolia Atlantica, p. 115, pi. 1, fig. 8, pi. 2, fig. 19, 1886. Cavolina tridentata Forskal, Verrill, Trans. Conn. Acad. Arts Sci., Vol. 5, p. 554, figs. 6, 7, 1882; Pelseneer, Rept. Voy. Challenger, Zool., Vol. 23, pt. 65, p. 83, 1887. Cavolina telemus Linnajus, A. Adams, Ann. Mag. Nat. Hist., Ser. 3, Vol. 3, p. 44, 1859; DaU, Bull. Mus. Comp. Zool., Harvard College, Vol. 43, no. 6, pp. 230-234, 1908; Suter, Man. New Zealand MoD., p. 55, pi. 6, fig. 3, 1913; Johnson, Boston Soc. Nat. Hist., Occasional Papers, Vol. 7, p. 156, 1915; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 113, pi. 1, figs. 6, 7, 1928. Type locality: Mediterranean Sea, Recent. Geologic range: Miocene to Recent (see below). Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 441 This Mediterranean and Atlantic species seems to be very widely distributed. It is likely that a critical study of abundant material would point to a further reduction in the number of forms in this genus that should retain distinctive specific names. Some of the shell differences, particularly differences in size, may be mere reflections of condi- tions of food supply or temperature, as mentioned by Dall. The north Pacific form Hsted below is given a separate varietal heading more to segregate the synonymy and references than to emphasize any possible valid distinction from a systematic standpoint. Cavolina telemus (Linnaeus) variety tricuspida (Rivers) Carolina telemvs Linnaeus, Carpenter, Brit. Assn. Adv. Sei., Rept. for 1863, pp. 612, 621, 646, 1864, reprinted in Smithsonian Misc. Coll., No. 252, pp. 98, 107, 132 (bottom pagination), 1872. Hyalxa tricuspida J. J. Rivers, Bull. Southern Calif. Acad. Sci., Vol. 3, no. 5, p. 69, May, 1904. Cavolina tridentata Forskal, Keep, West American Shells, p. 107, 1904; Revised Ed., p. 127, 1911. Cavolina ocddentalis Dall, Bull. Mus. Comp. Zool., Harvard College, Vol. 43, no. 6, p. 233, pi. 12, figs. 1, lb, Ic, October, 1908; U. S. Nat. Mus., Bull. 112, p. 59, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 19, 1927. Shell opaque white; dorsal plate widely convex; smooth on the disc; a lateral spine on either side and a terminal appendage short and truncate behind ; parallel to the lateral spines is a carina ; on the disc of the other side are five longitudinally situated carmae; aperature sharply truncate on dorsum, but strongly rounded on the opposite plate; the slit reaching quite to the lateral spines. Dimensions: Longitude 8 mm., latitude 7 mm. (Rivers.) Type specimen: Of occidentalis, in the U. S. National Museum, No. 110,591. Type localities: Of tricuspida, Santa Monica Mountains, presumably near Santa Monica, Los Angeles County, California, stated to be Pleistocene ; of occidentalis, north- east Pacific Ocean, between latitudes 30° and 54° North, Recent. Pleistocene: At the tj^pe locality of tricuspida; embankment on west shore of Spanish Bight, San Diego Bay, California (Mrs. Kate Stephens, MS.). Recent: North Pacific to southern CaUforiiia. Although the form from the Pacific coast of North America may not have sufficient distinguishing characteristics to separate it from the typical form, it has been retained tentatively as a doubtful variety, until more specimens from the Atlantic and Pacific can be carefully compared.^ Unfortunately Rivers did not figure the shell he named tricuspida, and his type is probably lost ; but his description does not suggest any means of separating the Pleistocene shell from the Recent. It is very unusual for a Pleistocene shell to differ specifically from its living descendant; and for a pteropod, it would be practically out of the question. Furthermore, the living form is known on good authority to occur rarely in the Pleistocene deposit at North Island, San Diego Bay. Woodring has reported the Atlantic form, presumably the typical variety, from the Bowden formation, middle Miocene of Jamaica, and also questionably from the Gurabo formation, middle Miocene of the Dominican Republic. The typical form has also been reported as a fossil from several localities in Europe. ' The Pacific variety is said to be on the average smaller in size, w-ith shorter posterior points or spines, but these differences are not likely to be constant or significant. 442 San Diego Society of Natural History [Memoirs ORDER OPISTHOBRANCHIATA (Cephalaspidea) Family ACTEONIDAE Shell entirely external and capable of containing the entire animal; spiral, with projecting or depressed spire and moderately numerous whorls, the mternal whorl-partitions not absorbed; surface generally sculptured with spiral, punctured grooves; aperture rounded below, with or without columellar folds, provided with an operculum. (Pilsbry in Tryon's Man. Conch.) This family includes the operculate, opisthobranchiate moUusca which possess a radula, differing in the last feature from the Retusidce. The family includes several genera which date from the Mesozoic or earlier. Acteonina d'Orbigny^ lias for its type a species from the Carboniferous of Belgium. Tornatellcea Conrad^ extends back to the Lias, according to Cossmann,' and is represented in the lower Eocene of California by "Cinulia" pinguis Gabb,'* from the Martinez formation. Genus ACTEON Montfort, 1810 Acleon Montfort, Conch. Syst., Vol. 2, pp. 314-316, 1810; not Acta!OH Oken, 1S15, nor Fleming, 1828. Tornalella Lamarck, Hist. Anim. s. Vert., Vol. 6, pt. 2, p. 219, 1822. Type (by monotypy), Acteon tornatilis (Gmelin) = Voluta tornatilis Gmelin. Shell compact, with short spire and large, ovate body whorl; aperture over half the length of the shell, narrowed above, the columella l^earing a smgle, simple, spiral fold. (Pilsbrj^, in Trj'on's Man. Conch.) Geologic range: Cretaceous to Recent. Distribution: World wide in warm temperate waters. Solidula Fischer de Waldheim, the type of which is Voluta solidula Linnaeus, differs from Acteon in having the columellar fold very much heavier, typically bifid above, the deep groove being sometimes bordered by a small plait on the upper side. Subgenus ACTEON, s. s. Columella mergmg gradually mto the regularly rounded basal lip. Acteon (Acteon) traski Stearns Actseon traski Stearns, Nautilus, Vol. 11, p. 14, 1897; Proc. U. S. Nat. Mus., Vol. 21, p. 297, text figure, 1899; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 188, pi. 10, fig. 6, 1903. Acteon traski Stearns, T. S. Oldroyd, Nautilus, Vol. 28, p. 81, 1914; Dall, Bull. 112, U. S. Nat. Mus., p. 60, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 1.5, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 24, pi. 1, fig. 12, 1927. Type specimen: In the U. S. National Museum. Type locality: Spanish Bight, San Diego, California; Pleistocene. Pleistocene: Upper San Pedro series at San Pedro (Arnold) ; of Signal Hill, Long Beach, and Santa Monica, Los Angeles County (T. S. Oldroyd, coll.); Pleistocene of Spanish Bight (Stearns); upper Pleisto- cene of San Quintin Bay, Lower California, Mexico (E. K. Jordan). Recent: Catalina Island, California, to Panama (A. M. Strong). ' Prod. Paleo. Anim. Moll., Ray, 1849, fide Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 433, 1927. - Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 4, p. 294, 1860, monotype, T. bella Conrad, op. cit., pi. 47, fig. 23. 3 Ess. Palto. Comp., Vol. 1, p. 49, 1895. * Fide Stewart, op. cit., p. 433. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 443 This species is readily distinguished from the other described Pacific coast Pleistocene species by subgeneric characters. It is about the size of large specimens of A. puncto- ccelatus (about 15 mm. in length), but has five post-nuclear whorls (including the body whorl) instead of four. Subgenus RICTAXIS Ball, 1871 Ridaxis Dall, Amer. Journ. Conch., Vol. 7, p. 1.36, pi. 15, fig. 12, 1871 ; Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 236, 1908. Adxonidea Gabb, Proc. Acad. Nat. Sci. Phila. for 1872, p. 273, pi. 11, figs. 8, 8A, Feb. 1873, monotype A. oryza Gabb. Type (by monotypy) , Tornatella punctoccelata Carpenter. Like Acteon, s. s., but with the columella projecting anteriorly or truncate obliquely. Acteon (Rictaxis) punctocaelatus (Carpenter) Tornatella punctocselata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 646, 1864; Journ. Conchyl., Vol. 12, p. 139, 186.5; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 267, 1888. Rictaxis punctocoelata Carpenter, Dall, Amer. Journ. Conch., Vol. 7, p. 136, pi. 15, fig. 12, 1871; Tryon, Struc. Syst. Conch., Vol. 2, p. 356, pi. 87, fig. 28, 1883. Rhextaxis punctocoelata Carpenter, Keep, West Coast Shells, p. 125, fig. 115, 1888; 1892. Actseon punctocsehitus Carpenter, Pilsbry, in Tryon, Man. Conch., Vol. 15, p. 166, pi. 49, figs. 24, 1893; Stearns, Nautilus, Vol. 11, p. 15, 1897; Proc. U. S. Nat. Mus., Vol. 21, p. 298, 1899. Action punctocoelalus var. coronadoensis, Stearns, Proc. U. S. Nat. Mus., Vol. 21, p. 299, 1898. Acta'on {Rictaxis) punctocoelata Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 189, pi. 9, fig. 6, 1903. Acteon punctocselatus Carpenter, T. S. Oldroyd, Nautilus, Vol. 28, p. 81, 1914. Acteon {Rictaxis) punctocoelata Carpenter, Dall, Bull. 112, U. S. Nat. Mus., p. 60, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, pp. 24, 25, pi. 1, figs. 17, 17a, 1927. Acteon punctocoelalus Carpenter, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925. Acteon punctocoelata Carpenter, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Acteon punctocoelalus vancouverensis I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 25, pi. 1, figs. 19, 20, 1927. Type specimen: In the U. S. National Museum. Type locality: Santa Cruz ?, California. Pleistocene: (As A. punctocaelatus): Lower San Pedro of Deadman Island and San Pedro; upper San Pedro at San Pedro; Pleistocene of Spanish Bight, San Diego (Arnold); lower San Pedro at Nob Hill, San Pedro (T. S. Oldroyd) ; upper San Pedro at Signal Hill and at Santa Monica (T. S. Oldroyd collec- tion); upper Pleistocene of San Quintin Bay, Lower California, Mexico (E. K. Jordan, 1926). (As A. punctocselatus var. coronadoensis): Pleistocene of Spanish Bight, San Diego (Stearns); upper San Pedro at Signal Hill and at Santa Monica, Los Angeles County (Oldroyd Collection). (As A. punct-ocsslatus vancouverensis): Upper San Pedro at Signal Hill and at Santa Monica (Oldroyd Collection). Recent: Monterey, California, to Magdalena Bay, Lower California, Mexico (Dall, 1921). Carpenter described this species briefly in the British Association Report for 1863, and later more adequately in the Journal de Conchyliologie for April, 1865. The dimen- sions given are "Long. .2, long. spir. .06, lat. .09, poll.; div. 50°." Specimens that are generally classified as A. punctoccelatus Carpenter from San Pedro are very much larger than Carpenter's measurements indicate. Specimens in the Oldroyd Collection at Stan- ford University are relatively enormous, the largest being three-quarters of an inch (about 20 mm.) in axial length. Stearns described as the variety coronadoensis elongate specimens collected from the Pleistocene deposit at Spanish Bight, San Diego, which had lost the color markings. In the Oldroyd Collection there are Recent specimens from La JoUa labeled coronadoensis, some of which seem to fit Stearns' brief description. Some do not have the "broad dark bands," while others do. They are "attenuated and delicate" and range in size from about 6 mm. to 9 mm. in axial length. The smallest is larger than 444 San Diego Society of Natural History [ Memoirs Carpenter's type. Specimens from Vancouver Island average smaller than the large San Pedro shells. This smaller shell has been named Vancouver ensis. It appears to be a de- generate or impoverished race, but as specimens that are apparently identical occur with the large form in the upper San Pedro deposits of Signal Hill and San Pedro, it cannot be considered a geographic race. The variety coronadoensis also appears to occur in the Pleistocene deposits of Signal Hill (Oldroyd Collection). Therefore it appears that these so-called varieties are not based upon valid distinctions. The large San Pedro Recent specimens would be the most distinct from Carpenter's punctocwlatus, if size were used as a basis of separation. Acteo7} painei Dall is a wider, lower spired form described from a station off Catalina Island. Acteon (Rictaxis) painei Dall Acteon painei Dall, Proc. Biol. Soc. Wash., Vol. 16, p. 172, 190.3; Bull. 112, U. S. Nat. Mus., p. 60, pi. 3, fig. .5, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 1, pp. 25, 26, pi. 1, fig. 18, 1927. Type specimen: In the U. S. National Museum. Type locality : Near Avalon, Catalina Island, California. Recent: Off Catalina Island, in 50 fathoms (Dall). This species differs from A. punctoccelatus by being relatively much broader, with a lower spire. The type was described as having a length of 8 mm. and a breadth of 5 mm. Acteon (Rictaxis) painei Dall, variety grandior, new variety Plate 24, Figure 12 Shell like that of typical -painei but more cylindrical in shape and about twice as large. Dimen- sions: Length, 18 mm., slightly imperfect, complete length probably about 19 mm.; diameter, 10.5 mm. Type specimen: San Diego Society of Natural History, No. 208. Type locality: Holser Canyon, Los Angeles County; middle Pliocene. Pliocene: At the type locality. The new variety grandior has a more nearly cylindrical body whorl than the typical variety of painei. The profile of the body whorl of the fossil is nearly straight to a point near the base where it curves in more suddenly than on the typical form. Both shells have about twenty-three flat, strap-like, spiral ribs separated by punctate interspaces. The fossil variety is decidedly larger than the living variety. Family RETUSIDAE (ACTEOCINIDAE) Shell spiral, cylindrical, or fusiform, external, capable of containing the soft parts; spire short or sunken and concealed, the apex more or less oblique to the shell axis; aperture long and narrow, wider below ; columella simple or with a fold ; umbilicus none or very narrow. Animal with the foot shorter than the shell, entire behind; headshield short, quadrangular, produced in two erected processes behind, near the bases of which are the eyes. Radula-teeth wanting; gizzard armed with three oval, tuberculate plates. (Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 5, p. 180, 1893, description of Acteodnidce, altered.) This family differs from the Acteonidce in the lack of the operculum and the radula. Pilsbry and others have pointed out that it is difficult to place some of the species in the Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 445 proper genera by the use of shell characters, but several authors have stated that the an- atomy is distinctive and significant. The name Retusidce is used here in preference to Acteocinidce because Retusa is an older name than Acteocina and because the conchological differences between the two groups are small and so variable that they do not appear to be of full generic significance. The International Commission on Zoological Nomenclature has not formulated any inflexible rules applying to family names, but it seems advisable to base the family names on the oldest valid generic name. Acteocina is here considered as a subgenus of Retusa. In the Pleistocene and Recent faunas of the Pacific coast there are a number of species of the Reiusidce, most of which are not well known. The shells are rather variable, and until the anatomy of the animals is known and can be correlated with shell characters, some of the confusion which has occurred in this group is apt to continue. Misidentifica- tions have been made, because many of the types have not been available, and what figures there are in the literature are not always helpful or reliable. For a discussion of the ranges of some of the Recent Pacific coast species, the reader is referred to papers by A. M. Strong and W. H. Dall.^ Genus RETUSA Brown, 1827 Retusa Brown, lUust. Conch. Gr. Brit. Irel., pi. 38, figs. 1-6, 1827; Pilsbry in Tryon's Man. Conch., Ser. 1, Vol. 15, pp. 203, 204, 1893; Sykes, Proc. Malac. Soc. London, Vol. 6, p. 31, 1904; Iredale, Vol. 11, p. 300, 1915; Woodring, Carnegie Inst.. Publ. Xo. 385, p. 119, and footnote, 1928. Uiriciilus Brown (in part), lUust. Conch. Gr. Brit. Irel., Ed. 2, p. 58, 1844; not of Schumacher, 1817, {Conidx). ? Tornalina A. Adams, in Sowerby, Thes. Conch., Vol. 2, p. 554, 1850. Type (see below), Bulla obtusa Montagu (= f plicata Brown = ? discors Brown, = ? Valuta alba Kanmacher, fide Iredale, 1915, and Woodring, 1928) ; figured by Montagu, Test. Brit., pi. 7, fig. 3, 1803. Although there has been some uncertainty in regard to the genotype of Retusa, the three supposedly different species originally included in the genus by Brown are appar- ently all congeneric, and hence the definition of the genus is clear. "Bulla" obtusa, the type of Retusa, is a small, somewhat cylindrical shell without a columellar plication and with a small spire which varies considerably in height and may even be truncated, the apex sometimes turned inwards. Jeffreys^ has given an excellent description of the species. Subgenus RETUSA, s. s. Columella without plications; iimer Up incrusted with callus, which may be sharply delimited; umbilicus closed or a mere chink. Retusa obtusa (Montagu), the type of Retusa, is circumboreal and has been reported by Dall to range from the Arctic Ocean to St. Matthew Island. Retusa semen (Reeve) has a depressed spire, but belongs in Retusa, s. s., rather than in Coleophysis. R. pertenuis (Mighels), which occurs in Bering Sea, is a typical Retusa. Acteocina smirna Dall, of the Lower California coast, is very close to R. recta (d'Orbigny). These two latter species have an obscure fold on the columella and illustrate the close relationship between Retusa and Acteocina. Retusa harpa (Dall) has the fine axial sculpture of Coleophysis ' A. M. Strong, Nautilus, Vol. 35, pp. 44-48, Oct., 1921; W. H. Dall., Nautilus, Vol. 35, p. 96, Jan., 1922; A. M. Strong, Nautilus, Vol. 35, pp. 122-123, April, 1922. 2 Jeffreys, Brit. Conch., Vol. 4. pp. 423, 424, 1867; description reproduced and figure supplied by Pilsbry in Tryon's Man. Concii., Vol. 15, pp. 214, 215, pi. 23, fig. 51, 1893. 446 San Diego Society of Natural History [Memoirs Fischer,^ but the type of the latter has an involute spire, the outer lip extending the entire length of the shell: Retusa xystrum (Dall), which ranges from San Pedro to San Diego, belongs in the section Sulcularia Dall.- This section is very close to Coleophysis Fischer, but it has an apical perforation and no plication on the columella. The types of both Coleophysis and Sulcularia have fine axial sculpture, but the former has a very small fold or plication which is entirely absent on Sulcularia. Retusa xystrum (Dall)^ has fine axial strise. It is a very delicate, small shell, about 2 or 3 mm. in length. Retusa (Retusa) harpa (Dall) Tomatina harpa Dall, Amer. Journ. Conch., Vol. 7, p. 136, pi. 15, fig. 11, 1871; Keep, West Coast Shells, p. 12.5, 1888, 1892; Pilsbry, in Tryon's Man. Conch., Vol. 15, p. 186, pi. 22, fig. 16, 1893; Newcombe, Nautilus, Vol. 10, no. 2, pp. 17, 19, 1896; Baker, Nautilus, Vol. 16, p. 42, 1902; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 191, 1903. Relusa harpa Dall, Bull. 112, U. S. Nat. Mus., p. 61, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, .\rt. 22, p. 9, 1925; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 1, p. 33, pi. 2, fig. 3, 1927. Type specimen: In the U. S. National Museum. Type locality: Monterey, California; Recent. Pleistocene: Rare in upper and lower San Pedro series at San Pedro, California (Arnold, 1903); "not rare" in lower San Pedro fauna at Nob HiU, San Pedro (T. S. Oldroyd, 1925J. Recent: Queen Charlotte Islands, British Columbia, to San Diego (Dall). This species has axial ribs on the upper portion of the body whorl and on the pen- ultimate whorl. The whorls of the spire appear tabulate, and the nucleus is prominent and turned at an angle to the shell axis. Mature specimens range between 3 and 7 mm. in axial length. The shape and the smooth columella of this species are as in Retusa, s. s., but the prom- inent, protruding nucleus and the well-developed axial sculpture suggest that it may be- long elsewhere. It cannot belong in Coleophysis, as the type of that section has a shell with an involute spire. Subgenus ACTEOCINA Gray, 1847 Acteocina Gray, Proc. Zool. Soc. London for 1847, p. 160, 1847. Type (by original designation), Acteon wetherilli Lea, Miocene of New Jersey.* Shell small or medium sized, cylLndrical, spire low, suture channeled; nuclear whorls small, papillate, more or less submerged, coiled at an angle of about 90° to axis of post-nuclear whorls; aperture long, narrow, dilated, and rounded at anterior end ; columella bearing an oblique Ijasal fold emerging from aperture and merging into basal lip; sculpture absent or consisting of faint spiral grooves. (Woodring, Carnegie Inst. Publ., No. 385, p. 119, 1928.) According to Woodring, ^ the earliest American species of this genus is from the upper Oligocene Byram marl. The "Acteocina" chehalisensis Weaver,* of the "Molopophorus lincolnensis zone" of Washington (lower or middle Oligocene), is an Acteon, and belongs in the preceding family. 1 Man. Conchyl., p. 555. Dec. 20, 1883, type (by monotypy), L'triculus truncatulus Bruguiere; Recent, European seas. 'U. S. Nat. Mus., Bull. 112, pp. 61, 202, Feb. 24, 1921, type, by original designation (p. 202), Relusa sulcata (d'Orbigny) = "Bulla" sulcata d'Orbigny. ' Proc. U. S. Nat. Mus., Vol. 56, p. 297, 1919. > Acteon wetherilli Lea, Contr. Geol., p. 213, pi. 6, fig. 224, 1833; said to be related to or identical with T. recta Gabb (as of d'Orbigny), fide Dall, Trans. Wagner Inst. Sci., Vol. 3, pt. 1, p. 15, 1890. s Carnegie Inst., Publ. No. 385, p. 119, 1928. » Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 55, pi. 4, figs. 55, 56. 1916. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 447 Retusa (Acteocina) culcitella (Gould) Plate 24, Figure 13 Bulla (Akera) culcitella Gould, Boston Journ. Nat. Hist., Vol. G, ro. 3, pp. 377, 378, pi. 14, fig. 8, Oct., 1853. Bulla {Tomatina) cerealis Gould, Boston Journ. Nat. Hist., Vol. 6, p. 378, pi. 14, fig. 9, Oct., 1853. Tomatina culcilella Gould, Carpenter, Proc. Zool. Soc. London for 1856, p. 227, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, p. 646, 1864; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 88, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 268, 1888; Keep, West Coast Shells, p. 125, fig. 114, 1888; 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 195, 1892; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 189, pi. 50, fig. 38, 1893; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 190, pi. 10, fig. 3, 1903. Tornalina cerealis Gould, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 647, 1864; Cooper, 7th .Ann. Rept. Calif. St. Mineralogist, p. 267, 1888; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 188, pi. 5, figs. 39, 40, 1893; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 189, pi. 10, fig. 5, 1903; Berry, Nautilus, Vol. 22, p. .38, 1908; Dall, Bull. 112, IT. S. Nat. Mus., p. 202, 1921. Acteocina culcitella Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 61, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 149, 155, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 27, pi. 2, figs, la, 16, Ic, 1927. Shell large, almost cylindrical; spire low, conical, of about three whorls; suture deep, appearing channeled; aperture long, narrow above, rounded and ample below; outer lip sunple, sharp, outline of margin convex anteriorly: columellar fold prominent; sculpture consisting of microscopic spiral striae and minute, broadly-curved growth lines; color white, generally shaded with fine, closely-spaced browai lines. Size, ranging up to 22 mm. in axial length and 9 mm. in width of body whorl. Type locality: Santa Barbara, California; Recent. Pliocene: Upper Pliocene at Bath-house Beach, Santa Barbara (.Arnold, 1903; Berry, 1908, the latter as cerealis). Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (E. K. Jordan, 1924); lower San Pedro series at San Pedro and vicinity (Arnold, 1903; T. S. Oldroyd); Pleistocene at Barlow's Ranch, near Ventura (Arnold); lower Pleistocene at Harmon Canyon, Ventura Co., Calif. (S. D. S. N. H. loc. 236, U. S. G., collector); mouth of Elk River, Oregon (Arnold and Hannibal, col- lectors) ; upper San Pedro series at San Pedro and vicinity (Arnold, 1903; T. S. Oldroyd) ; upper Pleis- tocene of San Quintin Bay, Lower California, Mexico (E. K. Jordan, 1926); Pleistocene at Twenty- sixth street and Spanish Bight, San Diego (Arnold, 1903; Mrs. K. Stephens); upper San Pedro Pleistocene at Signal Hill (T. S. Oldroyd); upper San Pedro Pleistocene at Santa Monica (F. C. Clark, T. S. Oldroyd, collectors); Pleistocene north of Arroyo Santa Rosa, Ventura County (S. D. S. N. H. loc. 233, U. S. G., coUector). Recent: Alaska to Scammons Lagoon, Lower California, Mexico (E. K. Jordan, 1924). This species is quite variable in size. Until recently, small specimens have been called cerealis Gould. Large specimens with the anterior portion of the shell larger than the pos- terior have been separated as a distinct species. The spire of this latter form is quite low and has a recognizably different appearance. As it may represent an incipient new sub- species, we have regarded its name as of varietal standing {A. culcitella var. pedroensis T. S. Oldroyd). Mr. Willett has separated the form with no excavation at the apex and with a very weak or obsolete columellar fold as sub-species intermedia.^ The single specimen upon which the Harmon Canyon lower Pleistocene record is based is large and shaped somewhat like variety pedroensis Oldroyd ; but as the spire is lacking and it is somewhat intermediate in shape, we have applied to it the older name. Acteocina eximia Baird is closely related, but the spire is in an excavation at the apex of the shell. Mr. George Willett of the Los Angeles Museum, a careful worker on Recent shells, considers^ exiynia a subspecies of culcitella. ' Nautilus, Vol. 42, no. 2, p. 38, Oct., 1928; type in Los Angeles County Museum; type locality, Catalina Island, in 30 fathoms. ' Nautilus, Vol. 42, p. 37, 1928. 448 San Diego Society of Natural History [Memoirs Retusa (Acteocina) culcitella (Gould) variety pedroensis (T. S. Oldroyd) Acteocina pedroensis T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, pp. 23, 24, pi. 2, fig. 9, 1925. Type specimen: In the U. S. National Museum. Type locality: Nob Hill, San Pedro, Los Angeles Co., California; lower San Pedro series, Pleistocene. Pleistocene: Lower San Pedro fauna of Nob Hill, San Pedro, California (T. S. Oldroyd, 1925). This is a large form with the anterior portion somewhat larger than the posterior. The spire is quite low and the columellar fold well developed. The distinction is of doubt- ful value. Retusa (Acteocina) culcitella (Gould) variety eximia (Baird) Tornatina eximia Baird, Proc. Zool. See. London for 1863, p. 67, 1863; Carpenter, Brit. Assn. Adv. Sei., Kept, for 1863, p. 647, 1864; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 268, 1888; PUsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 189 (no figure), 1893; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 190, pi. 10, fig. 11, 1903; E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2, (p. 42), 1919. Acteocina eximia Baird, Dall, Bull. 112, U. S. Nat. Mus., p. 61, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 28, pi. 2, fig. 6, 1927. Acteocina culcitella eximia Baird, Willett, Nautilus, Vol. 42, p. 37, 1928. Type specimen: In the British Museum. Type locality: Esquimalt Harbor, Vancouver Island, Recent. Pliocene: San Diego well, Balboa Park, San Diego (Cooper). Pleistocene: "Pliocene" of Deadman Island, Los Angeles County (Arnold); lower San Pedro of Nob Hill, San Pedro (Oldroyd, 1925); San Diego Pleistocene (Cooper); Pleistocene of the Chiton bed. Point Firmin, Los Angeles County (E. P. and E. M. Chace). Recent: Kodiak Island, Alaska, to Puget Sound (Dall, 1921). This species differs from typical culcitella in its lower spire, which is set in a circular depression just within the upper margin of the body whorl, in its longer aperture, and in its less prominent columellar fold. The variety intermedia Willett does not have the excava- tion at the base of the spire. We have seen no specimens of eximia as large as some speci- mens of culcitella. Retusa (Acteocina) angustior (Baker and Hanna) Acteocina angustior Baker and Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 124, pi. 4, fig. 5, April, 1927; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, pp. 142, 147, April, 1927. Type specimen : In the California Academy of Sciences. Type locality: Puerto Escondido, Lower California, Mexico; Recent. Pliocene: Marquer Bay, Carmen Island, Gulf of California, Mexico (Hanna and Hertlein, 1927) . Recent: Gulf of California, Mexico (Baker and Hanna). This form is distinguished from A . culcitella (Gould) by the more cylindric shape and smaller size. The type has a length of 5.4 mm., and a diameter of 2.0 mm. Retusa (Acteocina) infrequens (C. B. Adams) Bulla (Tornatina) infrequens C. B. Adams, Ann. Lye. Nat. Hist. N. Y., Vol. 5, p. 214 (pagination of separate), 1852; Carpenter, Proc. Zool. Soc. London, p. 358, June, 1863. ? Bulla (Tornatina) gracilis Menke, Zeitschr. Mai., 1850, p. 162, not of Adams, julc Pilsbry, 1893. Tornatina infrequens C. B. Adams, Carpenter, Brit. Assn. Adv. Sei., Rept. for 1856, p. 250, 1857; Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 171, 1857; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 668, 1864; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 187 (no figure), 1893. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 449 Acteoanainfrequens C. B. Adams, Dall, Bull. 112, U. S. Nat. Mus., p. 64, 1921; Strong, Nautilus, Vol. 35, p. 123, 1922; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 1, p. 29, 1927. Type specimen: At Amherst College, Massachusetts. Type locality: Panama. Pleistocene: Lower San Pedro at Nob Hill, San Pedro ("not rare," T. S. Oldroyd, 1925); Plei.stoeene at Santa Monica (Dall, erroneously as Recent, see Nautilus, Vol. 35, p. 96, 1922). Recent: Cape San Lucas, Lower California, Mexico, to Panama (Strong, 1922); Scamnions Lagoon, Lower California (Oldroyd Collection). This is a Panama species, extending north to Cape San Lucas. In the Oldroyd Col- lection at Stanford University there are fifteen specimens of infrequens collected by Henry Hemphill in Scammons Lagoon. These are apparently Recent specimens, which thus extend the known living range northward. "T. infrequens is distinguished by the Oliva-like spire, more or less elevated and deeply channeled along the suture. The body whorl is not swollen anteriorly, and the fold lies slanting on its base. Long. .14, long. spir. .03, lat. .05 [inch]." (Carpenter, Maz. Cat., p. 171.) Retusa (Acteocina) carinata (Carpenter) Tornatina carinata Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 171, 1857; Brit. Assn. Adv. Sci., Rept. for 18.56, pp. 250, 313, 1857; Rept. for 1863, pp. 551, 647, 1864; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 187, 1893; T. S. Oldroyd, Nautilus, Vol. 28, p. 81, 1914; Zetek, Moll. Panama, p. 521, 1918. ActeoHna carinata Carpenter, Dall, Bull. 112, U. S. Nat. Mus., p. 61, 1921; Strong, Nautilus, Vol. 35, p. 122, 1922; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 30, 1927. Smaller than infrequens, with the suture not channeled, and the shoulder sharply carinated. Type specimen: In the British Museum. Type locality: Mazatlan. Pleistocene: Upper San Pedro at Signal Hill, Los .4ngeles County (T. S. Oldroyd); upper San Pedro at Santa Monica, Los Angeles County (Oldroyd Collection); upper Pleistocene at San Quintin Bay, Lower California, Mexico (E. K. Jordan, 1926). Recent: San Diego to Mazatlan. Retusa (Acteocina) tumida (T. S. Oldroyd) Tornatina tumida T. S. Oldroyd, N.autilus, Vol. 34, no. 4, p. 116, pi. 5, fig. 8, .\pril, 1921. Acteocina tumida T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925. Type specimen: In the U. S. National Museum. Type locality: Nob Hill, San Pedro, Los Angeles County, California; lower Pleisto- cene. Pleistocene: Lower San Pedro series at Nob Hill, San Pedro (T. S. Oldroyd). This small species is characterized by the effuse anterior portion of the aperture. It is described as having a strong columellar plication, which places it in Acteocina. It has been reported only from the lower Pleistocene of Nob Hill (now removed) at San Pedro, California. 450 San Diego Society of Natural History [ Memoiks Genus VOLVULELLA Newton, 1891 Volimla A. Adams, in Sowerby, Thes. Conch., Vol. 2, p. 558, 1850; Bucquoy, Dautzenberg, and DoUfus, Moll. Rous- sillon, Vol. 1, pt. 13, p. 533, 1886, type Volvula roslrala A. Adams, Recent of Australia, fide Woodring, Car- negie Inst., Publ. No. 385, p. 125, 1928; not Volvulus Oken, 1815, nor Brull^, 1835, Coleoptera; not Volvula Gistel, Naturg. Thierr. Hohere Schulen., p. VIII, 1848, Diptera. Volvulella R. B. Newton, Syst. List. Edwards Coll. Brit. Olig. Eoc. Moll. Brit. Mus., p. 268, 1891, new name for Volvula A. Adams. Tyj)e (by subsequent designation, Bucquoy, Dautzenberg, and Dollfus, 1886), Volvula rostrata A. Adams; Recent, Australia. Geologic range: Eocene to Recent. Distribution: Widespread in warm and temperate waters. This genus is characterized in general by the thin, spindle-shaped shell, the concealed spire, and the posterior spine. The anterior end of the aperture is dilated, the columella bearing a faint fold. Volvulella cylindrica (Carpenter) Volvula cylindrica Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 647, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 380, 1865; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 270, 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 195, 1892; Pilsbry, in Tryon's Man. Conch., Vol. 15, p. 239, unfigured, 1893; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 191, pi. 4, fig. 2, 1903; T. S. Oldroyd, Nautilus, Vol. 28, p. 81, 1914; not Volvula cylindrica Gabb, Trans. Amer. Phil. See, N. S., Vol. 15, p. 246, 1873, Miocene to Recent, Caribbean, = Volvula oxylala Bush. Volvulella cylindrica Carpenter, Dall, Bull. 112, U. S. Nat. Mus., p. 62, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 34, pi. 2, fig. 9, 1927. Type specimen: In the Boyce Collection {fide Oldroyd, 1927). Type locality: Santa Barbara, California. Pleistocene: Lower San Pedro at Deadman Island (Arnold, 1903); upper Pleistocene of Signal Hill (T. S. Oldroyd, 1914); Pleistocene of the lumber yard at San Pedro, upper Pleistocene at Santa Monica, California (in the collection of T. S. Oldroyd); Pleistocene at 26th St., San Diego (Arnold, 1903). Recent: Vancouver Island to Gulf of California. This species differs from V. cooperi Dall in the more produced posterior spine and the more prominent axial strise and growth lines. The spiral strise are very faint and are apt to be invisible or may be destroyed on many specimens. Volvulella cooperi Dall Volvulella cooperi Dall, Proc. U. S. Nat. Mus., Vol. .56, p. 297, 1919; Dall, Bull. 112, U. S. Nat. Mus., p. 02, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 34, 1927. Type specimen: In the U. S. National Museum. Type locality: Scammons Lagoon, Lower California, Mexico. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, California (T. S. Oldroyd, 1925, "not rare"). Recent: Point Sur, California, to Scammons Lagoon, Lower California, Mexico (Dall, 1921). This species is very close to cylindrica but has a much less pronounced posterior spine, which in the adult may be entirely lacking. It was described as having an entirely smooth surface. The type measured 9.5 mm. in length by 3.6 mm. in diameter. V. californica Dall^ is an elongate-ovate species and is distinguishable by shape from V. cylindrica and V. cooperi, which are cylindrical. V. panamlca, catharia, and callicera were described by Dall- from tropical waters. They apparently do not reach California. 1 Proc. U. S. Nat. Mus., Vol. 56, p. 298, 1919, type locality, off Santa Rosa Island, California. ' Proc. U. S. Nat. Mus., Vol. 56, pp. 298, 299, 1919. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 451 Family SCAPHANDRIDAE Shell spiral, external, the spire sunken or concealed. Animal with a short subquadrate foot, truncated or forked behmd; frontal disc without tentacles, the posterior lobes obsolete; epipodial lobes well develojjed. Radula liavmg the central tooth small, with a very large lateral on each side of it, and either a few smaller uncmi or none. Gizzard containmg three calcareous plates, which are not tuberculate. (Pilsbry m Tryon, 1893.) According to Pilsbry' "This family differs from Tornatinidce [Retusidce of the present paper] in the obsolescence of posterior lobes on the head-shield, in the well-developed radula, and the large lateral epipodial lobes. It differs from Bullidoe in the highly special- ized form of the radula-teeth and their small number in a transverse row." The classifica- tion of this family and of the genera assigned to it depends almost entirely on the anatomy of the animal. Genus SCAPHANDER Montfort, 1810 Bulla Linnffius, Syst. Nat., Ed. 10, p. 725, 17.58, not Bulla Linnaeus, op. HI., p. 427; type cited by Children, Quarterly Journ. Sci., Lit., .Arts, Vol. 15, p. 232, July, 1823, Bulla lignaria Linnaeus. Scaphander Montfort, Conchyl. Syst., Vol. 2, p. 335, 1810. Bullaria Rafinesque, Specchio delle Scienze o Giornale Eneiclopedico di Sicilia, Vol. 2, ro. 11, p. 142, Nov. 1, 1814; reprinted by Binney and Tryon in Complete Writings C. S. llafinesque on Ree. Fos. Conch., p. 17, New York, 1864, new name for Bulln Linnaeus. Assula Schumacher, Ess. Nouv. Syst. Hab. Vers Test., pp. 78, 258, 1817, monotype. Bulla lignaria Linnaeus. Tyije (by original designation), Bulla lignaria Linnseus, Recent, eastern north Atlantic and Mediterranean. Shell external, ovate, imperforate, reaching a large size; spire involute, apical perforation shallow, closed by a callus; aperture large, wide, anterior part broadly expanded; inner lip closely appressed; parietal wall covered with callus; sculpture consisting of narrow spiral grooves (Woodring, Carnegie Inst., Publ. No. 385, p. 126, 1928). Geologic range: Eocene to Recent. Distribution: Wide. The above synonymy may require some explanation. In the tenth edition of the Systema Naturae, Bidla is used by Linnseus for two different groups of animals. On page 427 Bulla is used as a subgeneric name for a group of crickets (Gryllus), and on page 725 Bulla is again used but this time for a group of opisthobranch mollusks. Page priority would favor the use of Bulla in entomology to the exclusion of the second Bulla, and the first rev ser of the generic nomenclature, who appears to have been Rafinesque, chose to relinquish the use of Bulla for mollusca, proposing the new name, Bullaria, to take its place. No type was stated at that time; but in 1823 Children cited Bulla lignaria Lin- nseus as the type of Bulla Linnseus, making Bulla lignaria automatically the type of Bullaria also. As this species had been used in 1810 as the type of Scaphander, and in 1817 as the type of Assula, the two later generic names must be considered exact syno- nyms of Montfort's. Fossil species of Scaphander may not always be readily assigned to the proper genus, unless well-preserved specimens are available. Aiys Montfort- has a fold on the columella, and the aperture projects over the vertex of the shell as a fold, in a manner somewhat similar to the manner in which the columellar fold projects above the apex of the body whorl. There are usually spiral striations on the shell, and typically a small umbilicus is present. Bullus Montfort differs from Scaphander in having a perforate apex. Haminoea ' Pilsbry, in Tryon, Man. Conch., Ser. 1, Vol. 15, p. 2-42, 1893. 2 Conchyl. Syst., Vol. 2, p. 343, 1810; type designated, A. cymbulus = Bulla naucum Linnteus. 452 San Diego Society of Natural History ( Memoirs Turton and Kingston differs from Scaphander in having a much thinner, more deUcate shell and in having the outer lip join the apex of the body whorl around a small depressed point, whereas in Scaphander the vertex is a concave area closed with callus. Very few species of Scaphander have been reported from the Tertiary of the Pacific coast. "Cylichna" costata Gabb' is an Eocene Scaphander, and Scaphander washingtonensis Weaver- occurs in the Lincoln horizon of the Oligocene of Washington. The Miocene has yielded three species. Scaphander jugularis (Conrad) Bulla jugularis Conrad, U. S. House of Representatives, Doc. 129, p. 19, July, 1855; U. S. Pacific R. R. Repts., Vol. 5, p. 328, pi. 7, figs. 62, 62a, 62fc, 1856; reprinted without figures by Dall, U. S. Geol. Surv., Prof. Paper 59, p. 170 (comments also on p. 22), 1909. Scaphander jugularis Conrad, Anderson, Proc. Calif. Acad. Sci., Ser. 3 (Geol.), Vol. 2, i.o. 2, p. 201, pi. 15, figs. 56, 57, 1905. Type locality: Miocene of Ocoya Creek, California. Miocene: Temblor formation (middle Miocene) of Kern River district, California. Conrad's original description and figure are hardly adequate to define the species, but F. M. Anderson described and figured Scaphander jugularis (Conrad) from the same region and probably the same beds. The species figured by Anderson is apparently a Scaphander and not an Atys, if the figure can be relied upon. Scaphander conradi Dall Scaphander conradi Dall, U. S. Geol. Surv., Prof. Paper 59, p. 22, pi. 6, fig. 3, April 2, 1909. Type specimen: In the U. S. National Museum. Type locality: Coos Bay, Oregon; Empire formation, U. Miocene. This appears to be a typical Scaphander. It has a "shorter and more broadly pyri- form profile" than S. jugularis (Conrad). Scaphander oregonensis Dall Scaphander oregonensis Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 22, 23, pi. 5, fig. 7, .\pril 2, 1909; Howe, Univ. Calif. Publ. Geol., Vol. 14, table opp. p. 93, 1922. Longer and narrower than S. conradi Dall. Type specimen: In the U. S. National Museum. Type locality: Coos Bay, Oregon; Empire formation, U. Miocene. Miocene: Empire formation, upper Miocene of Coos Bay, Oregon. Upper Pliocene (or Pleistocene); Coos conglomerate, Oregon (Howe, 1922). Genus CYLICHNA Loven, 1846 Bullina Risso, Hist. Nat. Europe Mdrid., Vol. 4, p. 51, 1826, not Bullina F^russac, 1822. Cylindrella Swainson, Treat. Malac, pp. 135, 326, 1840, type C. alba Sw., not Cylindrella Swainson, op. cil., p. 311, nor Cylindrella Pfeiffer, Wiegnian's Archiv f. Naturg., Vol. 1, p. 38, 1840. Cylichna Lovi^n, Index Moll. Scand., p. 10, 1846; Herrmannsen, Indicis Gen. Malac, Supplement, p. 42, 18-52, type, Bulla cylindracea Pennant; not Cylichnus Burmeister, Handb. der Entomologie, Vol. 4, p. 171, 1844, Coleop- tera, fids Pilsbry, in Tryon, Man. Conch., Ser. 1, Vol. 15, p. 287, 1893. ■ Geol. Surv. Calif.. Palaeo., Vol. 1, pp. 143, 144. 229 (in part), pi. 2, fig. 107, 1864. Stewart has discussed this species in his paper on Gabb's fossil type gastropods: Proc. Acad. Nat. Sci. Phila.. Vol. 78. p. 437, pi. 27, fig. 5, 1927. 2 Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 56, pi. 5, fig. 68, 1916, Molopophorus lincolnensis zone. VoLDME I ] Pliocene and Pleistocene Mollusca of California 453 Bullinella R. B. Newton, Syst. List Edwards Coll. Brit. Olig. Eoc. Moll., p. 265, 1891, new name for Cylichtia Loven, not Cylichnus Burmeister. Type (by subsequent designation, Herrmannsen, 1852), Bulla cylindracea Pennant, Recent, European seas. Geologic range: Cretaceous (?) to Recent. This genus includes small, cylindrical shells with the posterior end truncated and with the spire involute, leaving a small apical concavity. The aperture is long and narrow, dilated below, and the columella bears one oblique fold on its base. Sculpture is absent or confined to fine spiral striae and growth lines. Cylichnella Gabb^ difi"ers from Cylichna in possessing two columellar folds. The California Quaternary species, according to the shell characters, should belong in Cylichna and cannot be placed in Cyliclmella. Anatomical characters, now largely unknown, may require a revision of the group. The name Bullina Risso is preoccupied. Cylindrella Swainson was used in two differ- ent senses by its author in the same work, and the same name was used the same year by Pfeiffer. Bullinella Newton was proposed as a substitute for Cylichna Loven, as we now think unnecessarily, because it was formerly thought that Cylichnus Burmeister, 1844, preoccupied the name. The Pacific coast Recent species of Cylichna {Cylichnella of^authors) appear to inter- grade, according to A. M. Strong,- but Pacific coast collections do not yet contain large enough series to warrant definite conclusions. The five supposed species listed by Dall' appear to be supplied with several synonyms. Misidentifications have no doubt found their way into the literature, and the situation is somewhat confused. But two species of Cylichna have been reported from the Pliocene or Pleistocene of the Pacific coast. Cylichna alba (Brown) Volvaria alba Brown, lllust. Conch. Gt. Brit. Irel., p. 3, pi. 19, figs. 43, 44, 1827. Bulla triticea Couthouy, Boston Journ. Nat. Hist., Vol. 2, p. 88, pi. 1, fig. 8 (not pi. 2, as stated), 1838. Cylichna alba (Brown) Lov^n, Ofversight Vet. Akad. Forh., p. 142, 1846; Jeffreys, Brit. Conch., Vol. 4, p. 417, pi. 8, fig. la, 1867; Vol. .5, p. 223, pi. 93, fig. 6, 1869; Ann. Mag. Nat. Hist., Ser. 4, Vol. 10, p. 241, 1872; Sars, Moll. Arct. Norv., p. 283, pi. 17, figs. 15, 16, 1878; Pilsbry, in Tryon, Man. Conch., Ser. 1, Vol. 15, pp. 290, 291, 1893; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 192, pi. 10, fig. 18, 1903; T. S. Oldroyd, Nautilus, Vol. 28, p. 81, 1914. "Cylichna cylindracea Linnaeus," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 647, 1864, not of Linnseus; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 238, 1888. Cylichna elongata Locard, Coq. ]Mar. Cotes France, p. 25, 1892, fide Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 15, p. 291, 1893. Cylichnella {Bulinella) alba (Brown), DaU, Bull. 112, U. S. Nat. Mus., p. 63, 1921; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 73, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, p. 39, pi. 2, fig. 5, 1927. Type locality: Greenock, Britain. ' Proc. Acad. Nat. Sci. Phila. for 1872. pp. 273. 274. pi. 10, fig. 2, Feb. 11. 1873; type Bulla bidentata d'Orbigny, not of Gabb, which = Cylichnella ovumlacerli (Guppy), fide Pilsbrj', Proc. Acad. Nat. Sci. Phila. for 1921, pt. 2, p. 311, text figs. 6, 7, 1922. ^ Verbal communication. > U. S. Nat. Mus., Bull. 112, p. 63. Feb. 24, 1921. 454 San Diego Society of Natural History [Memoirs Pliocene: San Diego well, Balboa Park, San Diego (Cooper, 1888). Pleistocene: Lower San Pedro series at Deadman Island, Los Angeles County; upper San Pedro series at San Pedro, rare (Arnold, 1903) ; lower San Pedro at Nob Hill cut, Los Angeles County, "two specimens" (T. S. Oldroyd, 1925); Pleistocene at Signal Hill, two miles from Long Beach, California (T. S. Old- royd, 1914); Pleistocene of Spanish Bight, San Diego (.Arnold, 1903; Mrs. K. Stephens, MS.); Pleistocene at Barlow's Ranch, near Ventura (.Arnold, 1903); Pleistocene of the Palisades at Santa Monica (collection of F. C. Clark). Recent: Circumboreal ; Arctic Ocean to San Diego, California (Dall). This species is less elongate and less cylindrical than C. attonsa Carpenter. It does not have the anterior portion of the lip produced as much as does C. diegensis (Dall). The latter was described as having the apex minutely perforate. Carpenter and others have apparently confused some of the Pacific coast species of Cylickna, and some of the old identifications are doubtful. C. alba is very widespread and occurs in the Pliocene deposits of England. Cylichna petrosa (Conrad) Bullina petrosa Conrad, Amer. Journ. Sci., Ser. 2, Vol. 5, p. 433, fig. 11, 1848; Dall, reprint of original in U. S. Geol. Surv., Prof. Paper 59, p. 151, fig. 11, 1909, not Bulla petrosa Conrad, 1849 = Haminoea petrosa (Conrad). Cylichna petrosa Conrad, Amer. Journ. Conch., Vol. 1, p. 151, 1865. Cylichnelln- petrosa Conrad, Dall, U. S. Geol. Siu'v., Prof. Paper 59, p. 23, April, 1909. Miocene: "Of Columbia River, Oregon, near Astoria" (Conrad, 1848; Dall, 1909). Conrad's original description is as follows: "Narrow-cylindrical; margin of labrum straight, extremity elevated above the apex; spire slightly raised above the shoulder, which is oblique and angulated." Dall ( 1909) stated that the species had some resemblance to cylindracea but was more slender. Cylichna diegensis (Dall) CylichneUa (BuUinella) diegensis Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 300, 1919; Bull. 112, U. S. Nat. Mus., p. 63, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 40, 1927. CylichneUa diegensis Dall, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Type specimen : In the U. S. National Museum, No. 209071. Type locality: Off Point Loma, San Diego County, California, in 98 to 191 fathoms, muddy bottom. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (E. K. Jordan). Recent: "San Diego, California, to Cape San Lucas. Vancouver Island ?" (Dall, 1921). This species is distinguished by the anterior projection of the aperture and the much thickened pillar lip. It may be C. propinqua E. A. Smith' but not the ''Bulla ' propinqua of M. Sars. It may also be, in part, the "C. cylindracea Linnaeus" of Carpenter, 1864, not of Linnseus. Cylichna attonsa Carpenter Cylichna {' cylindracea, var.) attonsa Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 537, 1864; Proc. .\cad. Nat. Sci. Phila. for 1865, p. 58, April, 1865; Pilsbry, in Tryon'.s Man. Conch., Ser. 1, Vol. 15, p. 303, 1893. Cylichna (? var. attonsa) Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 603, 1864. Cylirh7ia .' cylindracea var. attonsa Carpenter, op. cit., p. 647, 1864. Cylichna attonsa Carpenter, op. cit., p. 683, 1864. CylichneUa {BullineUa) attoma (Carpenter), Dall, Bull. 112, U. S. Nat. Mus., p. 63, 1921, "San Diego" ?; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 40, pi. 2, fig. 8, 1927. ' Ann. Mag. Nat. Hist.. Ser. 4. Vol, 9. p. 351, 1872. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 455 Type specimen: In the Academy of Natural Sciences of Philadelphia (fide Oldroyd). Type locality: Puget Sound. Pleistocene: At mouth of Elk River, Oregon (Arnold and Hannibal collection, Stanford Univ.). Recent: Puget Sound (to San Diego, California, Oldroj-d, 1927). This species is so imperfectly known that records of its occurrence must be carefully verified. Dall gives the range merely as "San Diego, California," which is not consistent with Carpenter's original description and lists. It is quite possible that Carpenter re- described Cylichna alba, as he appears not to have considered that species in the references given above.' In the Arnold and Hannibal collection at Stanford University there are two specimens labeled ''CyUch?}a attonsa Cpr., ]\Iouth of Elk River, Ore." The largest measures 12 mm. in axial length, by 4 mm. in diameter. They do not fit the measurements of C. nucleola Reeve- nor C. occulta Mighels,' and they may be attonsa, although the measurements of that species suggest a different shape. Family BULLIDAE Shell wholly external, globose, oval or oblong-cylindric, with umbilicated vertex (rarely covered) and sunken spire, mottled color pattern and rather smooth surface; aperture as long as the shell, rising above the vertex, narrow above, dilated below; columella simply concave, with reflexed cres- centic callus and no fold. (Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 326, 1893.) Pilsbry separated the Bullas from the family Akeridce on the basis of considerable differences in anatomy. The Scaphandridw are somewhat similar in radular characters, although that family is carnivorous, while the Bullidce represent an exclusively herbiv- orous group. Genus BULLUS Montfort, 1810 Bulla Linnaeus, Syst. Nat., Ed. 10, p. 725, in part only, not of p. 427, 1758; Schumacher, Essai Nouv. Syst. Hab. Vers Test., p. 257, 1817; etc. Bullus Montfort, Conchy]. Syst., Vol. 2, pp. 330-332, 1810. Bullites Schlotheim, Tasch. Min,, p. 92, 1813, fide Sherborn, Index Anim., Sect. 2, p. 933; not of Gmelin, Syst. Nat., Ed. 13, p. 414, 1793. Bullea Blainville, Man. Malac, p. 477, Oct., 1825; type, Bulla ampulla LinnEeus, designated by Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 145, 1846. "Bullaria Ratinesque," 1815, Dall, et auct. Type (by monotypy) "Bulla ampulla de Lamarck" = Bulla ampulla Linnaeus. Shell attaining a large size, rather solid, ovate or globose; spire involute, with a small but deep apical perforation; aperture long, anterior end dilated, posterior end narrow and ex-tending above the vertex of the shell; imier lip a callus wash on the body whorl, columella simple, gently curvmg anteriorly into the outer lip, callus deposit heavy and sharply delimited, in typical species covering the umbilical region; sculpture absent or consisting of fine spiral grooves and growth Imes. Geologic range: Jurassic to Recent (fide Cossmann, Ess. Paleo. Comp., Vol. 1, p. 91, 1895. Distribution: Warm and temperate seas. The synonymy given above should be compared with that cited under Scaphander. The generic name Bulla Linnaeus was rejected for use in the Mollusca over a hundred years ago by Rafinesque. Since that time several generic names have been proposed for the ^ Mr. A. M. Strong has kindly called our attention to this confusion. 2 Last of the Arctic Voyages, Vol. 2, p. 393, pi. 32, fig. 2, 1855. ' Proc. Boston Soc. Nat. Hist., Vol. 1, p. 50, 1841; Boston Journal of Natural History, Vol. i. pi. 14, fig. 11, 1S44. 456 San Diego Society of Natural History [ Memoirs group. Bullus Montfort is four years earlier than Bullaria Rafinesque; and as Montfort clearly designated as type B. ampulla, the group should take the name Bullus. If the International Commission on Zoological Nomenclature should resurrect the use of Bulla ' for Mollusca, this name, which ought to have been forgotten long ago after its rejection as a homonym, will have to be used for the group now so well known under the name of Scaphander Montfort. This cannot be avoided unless it is assumed that Montfort desig- nated the type of Bulla Linnaeus when he cited the type of his own genus Bullus. Such an assumption is unwarranted and if done in other cases will lead to more confusion. If Bullus Montfort is rejected, Bullites Schlotheim, 1813 (also of Kruger, 1823, Geschichte der Urwelt, fide Iredale, Proc. Malac. Soc. London, Vol. 14, 1921) cannot be used, as that name is a homonym of Bullites Gmelin, 1793. Bullus punctulatus (A. Adams) Bulla punctulala A. Adams, in Sowerby's Thes. Conch., Vol. 2, pp. 577-578 (as punctata by mistake, not punctata Schroeter, corrected on p. 604), pi. 123, fig. 77, 1850; Carpenter, Proc. Zool. Soc. London for 1863, p. 359, 1864; Pilsbry, in Tryon's Man. Conch., Vol. 15, p. 341, pi. 37, fig. 39, pi. 36, figs. 29, 30, 1893; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 193, 1903. ? Bulla adamsi Menke, Zeitschr. f . Malak., p. 162, 1850, excl. synonymy, fide Pilsbry. "Bulla adamsii Menke," Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 162, 1857; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 230, 1888. Bullaria punctulata A. Adams, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 199, 1909. Shell oval, solid ; surface smooth, showing under a strong lens exceedingly close and fine, wavy striations; exterior indistinctly clouded with fiesh color on a lighter ground, and usually obscurely blotched with dark in two ill-defined girdles, the whole surface showing few or many dark dots shaded on the left side, white-edged on the right; interior of aperture marked with whitish lines, scarcely sho\ving the external markings ; vertex umbilicated, the uaterior of the umbilicus sculptured with deep spiral grooves, about a dozen in number; columella bearmg a heavy lunate callus, which is often browii-edged ; parietal callus thick and heavy. Altitude, 25 mm.; diameter, 16 mm. (From Pilsbry, much altered.) Pliocene: San Fernando, Los Angeles County (Cooper). Pleistocene: Upper San Pedro series of Deadman Island, Los Cerritos, Crawfish George's, and San Pedro (Arnold). Recent: Gulf of California to Lobos Islands, Peru (Dall, 1910). It is probable that this form and B. aspersus A. Adams, both described at the same time, are synonyms of B. panamensis Philippi,' described two years earlier; but the ma- terial is not at hand to settle this question. Bullus aspersus (A. Adams) Bulla aspersa A. Adams, in Sowerby's Thes. Conch., Vol. 2, p. 578, pi. 123, fig. 78, 1850; Sowerby, in Reeve's Conch. Icon., Vol. 16, Bulla, sp. 18, pi. 6, figs. 18a, 18b, March, 1868; Pilsbry, in Tryon's Man. Conch., Vol. 15, p. 341, pi. 36, figs. 25, 26, 27, 28, 1893. Bullaria aspersa A. Adams, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 199, 1909; Dall, Nautilus, Vol. 23, p. 23, 1918. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall). Recent: Panama to Paita, Peru (Dall, 1909); Galapagos ? Dall reported this species as collected by C. R. Orcutt from the Pleistocene of Mag- dalena Bay. It is possible that asjjersus is the same species as punctulatus; or, if distinct, the Magdalena Bay fossil may be punctulatus. These species are not well known and de- scriptions are not reliable unless based on the type specimens. ' Zeitschr. f. Malac, p. 141, unfigured, 1848. Volume I | PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 457 Bullus quoyanus (Dall) Bulla quoyii Gray, MS. Brit. Mus., A. .Adams, in Sowerby's Thes. Conch., Vol. 2, pp. 576, 577, pi. 123, Hg. 71, 1850; not Bulla quoijii Gray, Dieffenbach's New Zealand, Vol. 2, p. 243, 1843; Pilsbry, in Tryon's Man. Conch., Vol. 15, p. 348, pi. 39, fig. 71, 1893. "Bulla quoyi Gray," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 193, pi. 8, fig. 8, 1903. Bullaria quoyana Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 300, 1919, new name for Bulla quoyi A. Adams, 1850, not Gray, 1843; Bull. 112, U. S. Nat. Mus., p. 63, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 41, 1927. Type specimen: In the British Museum. Type locality: Galapagos Islands. Pleistocene: Upper San Pedro series of San Pedro, rare (Arnold). Recent: Catalina Island, California, to Acapulco, Mexico (Dall). Only a critical study of the Pacific coast "Bullas," based as far as possible on the type specimens, or lacking them, on topotypes, can settle the confusion that obscures these species. The records of occurrences given in this report are based merely upon the literature. Bullus gouldianus (Pilsbry) Bulla nebulosa Gould, A. Adams, in Sowerby's Thes. Conch., Vol. 2, p. 578, pi. 123, figs. 79, 80, 1850; Menke, Zeitschr. f. Malak., p. 162, 18.50; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1856, pp. 198, 233, 234, 237, 284, 289, 313, 352, 353, 1857; Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., pp. 172, 540, 1857; Proc. Zool. Soc. London for 1856, p. 220, 1857; Brit. Assn. Adv. Sci., Kept, for 1863, pp. 5.36, 540, 593, 599, 621, 646, 665, 667, 1864; reprinted in Smithsonian Misc. Coll., No. 252, 1872; Sowerby, in Reeve's Conch. Icon., Vol. 16, Bulla, sp. 6, figs. 6a, 66, 6c, Jan., 1868; Keep, West Coast Shells, p. 126, fig. 117, 1888, 1892; not Bulla nebulosa Schroeter, Archiv f. Zool. u. Zoot. (Wiedemann), Vol. 4, p. 20, 1804. Bulla gouldiana Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 340, pi. 36, figs. 22, 23, 24, 1893; Keep, West American Shells, p. Ill, fig. 97, 1904. Bullaria gouldiana Pilsbry, Dall, Bull. 112, U. S. Nat. Mus., p. 63, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, no. 7, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 41, 1927. Type specimen: In the British Museum. Type locality: Gulf of California; Guaymas ?. Pleistocene: Upper San Pedro at Signal Hill, Los .\ngeles County; upper San Pedro fauna at San Pedro (T. S. Oldroyd Collection); upper Pleistocene of San Quintin Bay, Lower California, Mexico (E. K. Jordan, 1926). Recent: Santa Barbara, California, to Mazatlan, Mexico (Dall, 1921). This large species is much thinner than B. ampullus. It is larger than any other Ameri- can form and has a characteristic pattern of coloration and microscopic sculpture. (Pils- bry, 1893.) The surface of the shell of this species is microscopically granulose. Bullus striatus (Bruguiere) Bulla striata Bruguiere, Encyel. Meth., Hist. Nat. Vers, Vol. 1, p. 372, 1792; Philippi, Enum. Moll. Siciha, Vol. 1, p. 121, 1836; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, pp. 332, 333, pi. 37, figs. 42-46, 1893. Bulla columns- Delia Chiage, Test. Utr. Sicil., Vol. 3, pt. 2, p. 24, pi. 46, figs. 17, 18, 1827. Bulla paupercula Sowerby, Quart. Journ. Geol. Soc. London, Vol. 6, p. .52, unfigured, 1850; Guppy, Vol. .32, p. 518, 1876. Bulla omphalodes Menke, Zeitschr. f. Malak., p. 137, 1853; Malak. Bliit., Vol. 1, p. 44, 1854, fide Pilsbry, 1893. Bulla dadylis Menke, Zeitschr. f. Malak., p. 137, 1853, fide Pilsbry, 1893. Bulla striata var. attenuata Dall, Trans. Wagner Inst. Sci., Vol. 3, pt. 2, p. 219, pi. 13, fig. 10a, 1890. Not "Bulla striata Bruguiere," Guppy, Geol. Mag., Decade 2, Vol. 1, p. 437, 1874; nor of Dall, Trans. Wagner Inst. Sci., Vol. 3, pt. 6, p. 1583, 1903, fide Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 130, 1928. Bullaria pauperctda Sowerby, Maury, Bull. Amer. Paleo., Vol. 5, p. 182 (No. 29, pp. 18, 19), pi. 3, fig. 8, 1917. Bullaria striata Bruguiere, Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, pp. 442, 443, pi. 20, fig. 9, 1926. 458 San Diego Society of Natural History [ Memoirs Pliocene: From the first narrow box canyon east of Alverson Canyon, Coyote Mt., Imperial County, Calif. (G. D. Hanna, 1926); Pliocene of Florida (Dall, etc.). Recent: Mediterranean; Atlantic coasts of Portugal and Morocco; also Florida. This species has microscopic spiral striations, with a few more prominent, more widely spaced grooves near each end of the shell. The umbilical perforation is wide, open, deep, and has closely-spaced spiral grooves within. Pilsbry has discussed the variations and distribution of this species in the reference given above. The "Bulla" petrosa Conrad (Miocene), of the U. S. Exploring Expedition Report, is a Haminoea, according to Dall. Family AKERIDAE Shell oval or cylindrical, //(//), and fragile, of a light yellowish brown or green tint, the spire low or concealed. (Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, p. 350, 1893.) Genus HAMINOEA Turton and Kingston, ? 1830 Haminoea Turton and Kingston, The Teigmonth, Dawlish, and Torquay Guide, pt. 2, Nat. Hi.st. of the District, p. ?, \S30, fide Iredale, Proc. Malac. !Soc. London, Vol. 11, p. 172, 1914; issued as separate "Enumer. Marine Shells Found on the Dartmouth Coast," 1829 "^Jide Cat. Nat. Hist. Books in Brit. Mus., Vol. .5, p. 215.5, 1915. f/a??rmea Leach MS., Gray, Proc. Zool. Soc. London for 1847, p. 161, 1847. Type (by subsequent designation for Haminca, Gray, 1847), Bulla hydaiis Linnsus, Recent, Atlantic coasts of Spain and France, and Mediterranean Sea. Geologic range: Miocene to Recent (Cossmann, Ess. Paleo. Comp., Vol. 1, p. 92, 1895). Distribution: World wide in tropic and temperate seas. This genus is characterized by its thin shell, which may be partly corneous and flexible, and is generally unicolored, with a thin epidermis, and has a simple and minutely perforated apex. The umbilicus is closed. The shape is ovate or ovate-cylindric and its appearance is much like that of Bullus, although the two genera are said to be very dis- tinct anatomically. Iredale has shown that the generic name dates from at least as early as 1830 and that the original spelling was with an "o." Haminoea cymbiformis Carpenter ? Bulla inrescens Sowerby, Genera of Shells, Pt. 39, fig. 2, 1833 (?), (for date see R. B. Newton, Cat. Edwards Coll. • Brit. Olig. Eoc. Moll. Brit. Mus., p. 322, 1891, and Shcrborn, Ann. Mag. Nat. Hist. Ser. 6, Vol. 13, p. 371, 1894.) ? Bulla (Haminea) virescens Sowerby, A. Adams, in Sowerby 's Thes. Conch., Vol. 2, p. 579, pi. 124, fig. 83, 1850. "Bulla (Haminea) virescens Sowerby," Gould, U. S. Pacific R. R. Reports, Vol. 5, p. 330, 1856. Haminea cymbiformis Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 174, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, pp. 545, 646, 1864, reprinted in Smithsonian Misc. Coll., No. 252, pp. 31, 132 (bottom pagina- tion), 1872. "Haminea virescens Sowerby," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 545, 646, 1864, reprinted in Smith- sonian Misc. Coll., No. 252, pp. 31, 132 (bottom pagination), 1872; Keep, West Coast Shells, p. 126, 1888, 1892; Dall, Trans. Wagner Inst. Sci., Vol. 3, pt. 1, p. 18, 1890; Williamson, Proc. IT. S. Nat. Mus., Vol. 15, p. 195, 1892; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 15, pp. 360, 361, 1893; Bradshaw, Nautilus, Vol. 8, no. 9, p. 101, pi. 2, fig. 15, 1895; .-Vrnold, Mem. Cahf. Acad. Sci., Vol. 3, p. 194, pi. 8, fig. IS, 1903; I. S. Oldroyd, Nautilus, Vol. 31, p. 98, 1918. Haminoea virescens Sowerhy, Dall, Bull. 112, V. S. Nat. Mus., p. 63, 1921; I. .S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 42, 1927. Haminoea dalli Bartsch, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925, nude name. Haminoea strongi Baker and Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, pp. 130-131, pi. 4, fig. 2, 1927. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 459 Type specimens: Of virescens, in the British Museum (?) ; of cymbiformis, in the British Museum, Mazatlan Collection; of strongi, at the California Academy of Sciences. Type localities: Of virescens, Pitcairn Island, southwestern Pacific (?) ; of cymbiformis, Mazatlan, Mexico; of strongi, Gulf of California, Mexico. ? Pliocene: Caloosahatchie beds, Florida (Dall, 1900). Pleistocene: Rare in the upper San Pedro series at San Pedro, Los Angeles County (Arnold, 1903); "plentiful" in the lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd, 1925, as "H. dalli Bartsch, new species"). Recent: Santa Barbara, California, to Puerto Libertad, Mexico (Dall, 1921); Puget Sound (Oldroyd, 1918); ? western Pacific; ? Atlantic. This species is characterized by the constriction of the apical portion of the shell and by the dilated anterior part of the aperture. The shell is thin and typically of a pale greenish color. A. M. Strong states that in southern California the form found in the lagoons and bays has a dark brown periostricum not found on specimens living in the open ocean. The specimens of "Haminoea dalli Bartsch, new species," collected by T. S. Oldroyd from Nob Hill, San Pedro Pleistocene, are apparently of this species; but the green color is gone, and the specimens do not attain the size reached by some large living individuals. Dall stated that the Florida Pliocene specimens of "virescens" were identical with Recent Pacific coast representatives. This species has been known for a long time under the name virescens (Sowerby), in spite of the fact that the type locality of Sowerby's species is given as Pitcairn Island, in the southwestern Pacific. Indeed, when the illustrations and descriptions of the eastern Pacific and western Pacific forms are compared, it is not surprising that the older writers, who had no preconceived opinions about the limited distribution of species, should con- sider the two the same. The California and the south Pacific form are surprisingly similar in shape, size, and even somet'mes in coloration, and objectively considered, there is practically nothing to distinguish them. It is possible that the two occurrences represent isolated remnants of a species that once had a continuous distribution around the borders of the north Pacific, as other species such as Psephcea prevostiana once had; and being a primitive type of shell, with few characters, it may have survived essentially unchanged on the opposite sides of the Pacific, driven southward in the later Cenozoic by the on- coming of colder temperatures. If the fossil record should give evidence to bear out this possible history, and if on careful comparison the two forms could not be separated ob- jectively, then the name virescens should again be applied to the California and Lower California shells. In the meantime, however, since the fossil record is not well known and the hypothesis of parallel development is at least equally plausible and is much more in favor among conchologists, it seems better to use a local name. The oldest available local name that has been applied to this species is cymbiformis Carpenter. It is unfortunate that Carpenter's type is a very young, imperfect specimen, not very fully described and never figured. Nevertheless, Carpenter himself identified it with virescens and abandoned his name in favor of Sowerby's older one, being followed in this respect by Dall, Arnold, and others. The evidence for the identification of Car- penter's name is none too satisfactory, but as much of it as there is all points to the con- clusion that Carpenter's species is the same as the California and west Mexican species generally known as virescens and more recently described as strongi by Baker and Hanna. Carpenter, being presumably the one who has known more about the shell he described than anyone else, and being in a position to know what was generally called virescens, 460 San Diego Society of Natural History [ Memoirs came to this conclusion; and at the same time he knew and recognized in his report the only other distinct species of Haminoea in the region, H. vesicula. As no evidence has been presented to show that Carpenter did not have the species here assigned to cymbiformis, the burden of the proof falls on those who wish to doubt his conclusions. His shell agrees, according to the description, with the figure and description of strongi in its thin shell, cymbiform shape, and very fine spiral striations. Thus the present writers conclude that the name strongi must fall as a synonym of the earlier cymbiformis. In a recent, very hurried visit to the British Museum, Mr. Gale found the type speci- men of cymhiformis, along with the rest of Carpenter's Mazatlan material, clearly marked with the original inscription. However, without comparative California and Lower Cali- fornia material, and in the very short time available, it was not possible to settle the morphological and nomenclatorial problems discussed above. Haminoea vesicula (Gould) Bulla [Haminea) vesicula Gould, U. S. Pacific R. R. Repts., Vol. 5, Appendix, p. 334, pi. 11, fig. 29, 1856 (Prelim. Rept., 1855, U. S. House of Representatives Doc. 129, not available). Haminea vesicula Keep, West Coast Shells, p. 126, fig. 116, 1888, 1892; ^Yest American Shells, p. 112, fig. 98, 1904. Haminoea vesicula Gould, Dall, Bull. 112, U. S. Nat. Mus., p. 63, 1921 ; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 9, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 42, 1927. Type specimen: In the U. S. National Museum. Type locality: San Diego, California; Recent. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, Los Angeles County, "not rare" (T. S. Oldroyd). Recent: Southeastern Alaska to the Gulf of California, Mexico. This species is not constricted near the apex, as are H. virescens (Sowerby) and cymhi- formis Carpenter. Mr. George Willett of the Los Angeles Museum has a specimen ap- parently of vesicula obtained by him at Ketchikan, southeastern Alaska, which extends the previously known range northward from Vancouver Island. Haminoea petrosa (Conrad) Bulla petrosa Conrad, U. S. Expl. Exped. (Wilkes), Vol. 10 (Geol.), p. 727, pi. 19, fig. 8, 1849. Cylichna oregona Conrad, Amer. Journ. Conch., Vol. 1, p. 151, 1865. Haminea petrosa Conrad, Arnold, Proc. U. S. Nat. Mus., Vol. 34, pi. 33, fig. 17, 1908; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 23, 1909. Type specimen: In the U. S. National Museum, No. 3607. Type locality: Miocene of Astoria, Oregon. Oligocene: On San Lorenzo River, three miles above the town of Boulder Creek, Santa Cruz County, Cali- fornia (.\rnold, 1908). Miocene: Astoria, Oregon. Dall, who had seen Conrad's type, stated that the species was undoubtedly a Ham- inoea. The original figure in the geology atlas of the Wilkes Exploring Expedition report conveys little idea of the characters of the shell except for the elongate, subcylindric shape and the truncate apex. It appears very little like typical Haminoea, and recalls some species of Cylichna. Arnold (1908) figured a specimen from the San Lorenzo forma- tion (Oligocene) of Santa Cruz County, but the figure is not similar to the shape suggested by Conrad's drawing. The two may not be conspecific. Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 461 ORDER PULMONATA Superfamily Akteophila Family ELLOBIIDAE Genus MELAMPUS Montfort, 1810 Melampus Montfort, Conchyl. Syst., Vol. 2, pp. 318-320, 1810; Herrmannsen, Indicis. Gen. Malac, Vol. 2, p. 27, July 17, 1847; Gray, Proc. Zool. Soc. London for 1847, p. 179, Nov., 1847; Dall, Proc. U. S. Nat. Mus., Vol. 8, p. 280, 1886. Conovulus Lamarck, Extr. Cours Zool., 1812; Bowdich, Elem. Conch., pp. 28, 63, 1822, ^e Dall. Rhodostoma Swainson, Treat Malac, p. 344, 1840. Type (by original designation), Bulimus coniformis Bruguiere = Bulla coffea Lin- n£eus, Syst. Nat., Ed. 10, p. 729, 1758; Barbados, Recent; figured by Dall, Proc. U. S. Nat. Mus., Vol. 8, pi. 18, fig. 3, 1886. Shell ovate-conic; spire low; aperture somewhat elongate, gently rounded below; inner lip pol- ished, but not incrusted, bearing plications; outer lip generally thin, simple, sometimes bearmg within lirations or a row of denticulations ; umbilicus closed or a mere chink ; no developed anterior canal nor posterior notch ; sculpture absent or reduced to growth lines. Size generally small, average length for genus about 12 or 15 mm. Geologic range: Tertiary to Recent. Distribution: Warm and temperate regions. The species of this genus inhabit bays, lagoons, tidal marshes, deltas, etc. They live either in quiet marine or brackish waters and can often be found crawling on the mud or on grasses. They are amphibious. The subgenus Leuconia Gray,' according to Dall, can be used for the forms with a produced spire and a somewhat thickened outer lip. Melampus olivaceous Carpenter Plate 24, Figure 16 Melampus olivaceous Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 178, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, p. 647, 1864; DaU, Proc. U. S. Nat. Mus., Vol. 8, p. 283, pi. 18, fig. 16, 1886; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 250, 1888; Keep, West Coast Shells, p. 124, fig. 113, 1888; 1892; Williamson, Proc. U. S, Nat. Mus., Vol. 15, p. 196, 1892; Arnold, Mem. Cahf. Acad. Sci., Vol. 3, p. 197, 1903; T. S. Oldroyd, Nautilus, Vol. 28, no. 7, p. 82, 1914; Dall, Bull. 112, U. S. Nat. Mus., p. 66, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, no. 7, p. 245, 1926; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, pp. 54, 55, pi. 1, fig. 16, 1927. Type specimen: In the Liverpool Collection. Type locality: Mazatlan, Mexico; Recent. Pliocene: San Diego well (Dall). Pleistocene: Signal Hill, near Long Beach, Los Angeles Coimty (T. S. Oldroyd); upper Pleistocene of San Quintin Bay, Lower CaUfornia, Mexico (Jordan). Recent: Monterey Bay (Salinas River), California, to Mazatlan, Mexico (Dall, 1921). There is only one living species of Melampus on the coast of California. It is a small, olive-brown, ovate-conic shell with indistinct revolving color bands intersected by growth lines and occasional axial color bands. Large specimens measure 10 mm. in length by 7 mm. in width. This species is not uncommon in the bays and lagoons of southern California. It frequently occurs on damp eel-grass just above tide level. ' Turton, Man., Ed. 2, p. 227, 1S40; Proc. Zool. Soc. London for 1847, p. 179. 1847; Turton. Man.. Ed. 3, p. 195, 1857. Dall (1886) cited "Valuta" bidentata Montagu as type of Leuconia, but Gray (1847) had already selected "Valuta alba" as type forty years previously. 462 San Diego Society of Natural History [Memoirs Superfamily Petrophila Family GADINIIDAE Genus GADINIA Gray, 1824 Gadinia Gray, Tilloch's Philos. Mag. (London), Vol. 63, p. 274, 1824; Gray, Proc. Zool. See. London, p. 181, 1847; Dall, Amer. Journ. Conch., Vol. 6, pp. 8, 9, 1870; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, fasc. 12, p. 483, 1886; Cos.smann, Ess. PaU-o. Conip., Vol. 1, p. 145, 1895. Clypeus Scacchi, Osservazioni Zoologiche, p. ?, 1S33, fide Dall. Mouretia Sowerby, Proc. Zool. Soc. London for 1835, p. 6, 1835; Gray, Proc. Zool. Soc. London for 1847, p. 181, 1847. "Murelia" Sowerby, d'Orbigny, Voy. Amer. Merid., Vol. 5, pp. 470, 682, 1846, in part, fide Dall, 1870. RowelHci Cooper, Proc. Calif. Acad. Nat. Sci., p. 188, 1865 ( = Gadinia jim., fide Dall, 1870). Type (fide Gray, 1847), Gadinia afra Gmelin {Lepas Gadin Adanson, 1857), west coast of Africa, Recent. Shell low, conical, or dome-shaped; apex blunt, central, or sulscentral; sculpture radial or irregu- lar; interior simple, without septum, an arcuate muscle scar above the margin. Animal an air- breather, with a Imig and without gills. Geologic range: Miocene to Recent (? Paleocene) , ^de Cossmann, 1895. Distribution: Warm and temperate seas; Mediterranean, Africa, Australia, North and South America, etc. The genus occurs at least as early as the Miocene, both in California and in Europe. The Paleocene record of Cossmann is based upon a species which is doubtfully a Gadinia. It is likely that imperfectly preserved fossil specimens of Gadinia have been mis- identified as Acma'a. Both of these genera have a conical shell and a horseshoe-shaped internal muscle scar; but the base of Gadinia is round, whereas that of Acmcea has a some- what elongate shape. The anatomy is vastly different. Calyptro'a differs in its spiral shell and internal spiral septum ; but some poorly preserved fossil Calyptraeas do not show the interior of the shell nor the spiral sutures and may simulate Gadinia. Hipponix is generally flatter, more irregular, and has coarser growth lamellae. All these genera, of course, are very different from each other, their similarities being quite superficial; but poor preservation often makes differentiation difficult. Gadinia is indicated as a homonym in Agassiz's Nomenclator, the name having had a prior use in Ichthyology by Rafinesque, 1815. Rafinesque's paper in which this name is used is not available to the present writers, but the use of Gadinia for fishes was probably not in a generic sense. It is not mentioned in Jordan's Genera of Fishes. Gadinia reticulata (Sowerby) Mouretia reticulata Sowerby, Proc. Zool. Soc. London, p. 6, 1835. Siphonaria reticulata Sowerby, d'Orbigny, Voy. Amer. M^rid., Vol. 5, p. 682, 1846. Gadinia reticulata H. and A. Adams, Gen. Ree. Moll., Vol. 1, p. 463, 1854; Dall, An er. Journ. Conch., Vol. 0, pt. 1, pp. 11, 12, pi. 2, figs. 1-9, pi. 4, figs. 1-3, 1870; ? Garrett, Journ. Conch., Ncl. 1, p. 335, 1878; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 422, 1915; Dall, Bull. 112, U. S. Nat. Mus., p. 66, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, pp. 55, 56, pi. 2, figs. 16a, 16b, 1927. Rowellia sp. Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 651, 1864. Rowellia radiata Cooper, Proc. Calif. Acad. Nat. Sci., p. 188 (jun.), 1865. "Gadinia stellala Sowerby" of some early California collectors, not of Sowerby, a variable Gulf of California shell, probably including pcntegoniosloina Sowerby, also described as a Mouretia. Type specimen: Presumably in the British Museum. Type locality: Not Valparaiso, Chile, ^de Dall, 1870. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 463 Miocene: I'pper San Pablo, upper Miocene, of central California (Clark, 1915). Recent: Trinidad and the Farallone Islands, California, to Cape San Lucas, Lower California (Dall, 1921). The shell of this species has the shape of a low cone or rounded dome. The apex is nearly central, but is inclined to be a little posterior. The tip of the spire, which is not twisted, may be eroded or submerged in the shell. The sculpture, when not eroded or obliterated by borings, consists of rounded radial ribs and annular growth lines and coarser ruga?. The interior of the shell has a muscle scar situated not quite half of the distance from the margin to the apex, the scar being not a complete circle. Full-grown individuals measure as much as 25 mm. in diameter and 12 mm. in height. The shell of this species is readily distinguished from that of the limpets by its rounded basal margin and peculiar radial sculpture. Lepeta is generally smoother on the exterior and is elongate. The specimen upon which the Miocene record is based has not been examined. Family SIPHONARIIDAE Shell patellif orm, unsymmetrical ; adductor impression on the shell interrupted by a lateral sinus corresponding to the pulmonary orifice and situated at the anterior side. (Cossmann, Ess. Paleo. Comp., Vol. 1, p. 135, 1895.) Genus WILLIAMIA Monterosato, 1884 Williamia Monterosato, Nomen. Gen. e. Spec, di Alcune Conch. Medit., p. 150, 1884; Woodring, Carnegie Inst., Publ. No. 385, p. Ill, 1928. Type (by monotypy), Ancylus f gussonii da Costa; Recent, Mediterranean {fide Woodring, op. cit., p. 111). Shell small, thin, patelliforra. Apex near posterior end, twisted to left. Aperture rounded, ovate. Muscle impression horseshoe-shaped, the anterior ends joined by a shallow groove, interrupted on the right side by a wide, obscure groove. Surface smooth or bearing obscure radial waves. (Wood- rmg, 1928.) This genus differs from Siphonaria Sowerby' in that its apex is spirally twisted to the left. This character is not always evident, as many specimens of IF. peltoides have a blunt, recumbent apex that is either partly eroded or submerged in the cone-shaped exterior surface of the shell. It must not be confused with the eccentric position of the apex of such species as Siphonaria thersites Carpenter, which has a lopsided appearance because the apex is situated to the left of the geometric center of the shell. Both genera are sedentary groups of moUusks. Dall has discussed the anatomy of the Siphonariida' in Volume 6 of the American Journal of Conchology. Williamia peltoides (Carpenter) Nacella sp. ind.. Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 202, 1857. Nacella peltoides Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 474, June, 1864; Brit. Assn. Adv. Sci., Rept. for 1863, pp. 545, 618, reprinted in Smithsonian Misc. Coll., No. 252, pp. 31, 104, (bottom pagination), 1872. Siphonaria peltoides Carpenter, Dall, Amer. Journ. Conch., Vol. 6, r,o. 1, p. 37, pi. 4, figs. 11a, 116, 1870. Nacella f vernalis Dall, Amer. Journ. Conch., Vol. 6, no. 1, p. 37, pi. 4, figs. 11a, 116, 1870, in synonymy. Siphonaria {Williamia) peltoides Dall, Stearns, Proc. U. S. Nat. Mus., Vol. 16, p. 384, 1893. Williamia peltoides Carpenter, Dall, Nautilus, Vol. 21, no. 8, p. 86, 1907; ? U. S. Nat. Mus., Bull. 112, p. 67, pi. 15, figs. 10, 12, 1921; ? L S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 1, p. 58, pi. 2, fig. 17, 1927. ? Williamia vernalis Dall, U. S. Nat. Mus., Bull. 112, p. 67, 1921; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 58, pi. 2, figs. 19a, 196, 1927. ' Genera of Shells, Siphonaria, 1824; type (Gray, 1847) S. sipho Sowerby. 464 San Diego Society of Natural History [ Memoirs Type specimens: Of peltoides, in the Liverpool Collection; of vernalis, in the U. S. National Museum ? Type locality: Cape San Lucas, Lower California, Mexico; Recent. Pleistocene: Upper San Pedro fauna at Santa Monica, Los Angeles County (T. S. Oldroyd, collection). Recent: Crescent City, California, to the Gulf of California. From Carpenter's comparison of this species in "size and shape" with Ancylus fluviatilis in the Mazatlan Catalogue and his later description in the Annals and Magazine of Natural History, it seems certain that he was applying a name to the more common of the two California Williamias. Dall (1870) early recognized Carpenter's species, re- described and figured it, and placed in its synonymy his own manuscript name "vernalis." Ball's later attempt to assign Carpenter's specific name to the much rarer form with the elevated, somewhat dilated summit and down-curved apex, appears contrary to the facts and must be rejected. The latter form has no radial color markings, or they are reduced to faint traces near the margin of the aperture. It seems probable that there is but one species, the higher form with hooked apex being merely a morphologic response to the less rigorous habitat on broken shells and small rocks beyond the direct pounding of the surf. The common form, "of the shape and size of Ancylus fluviatilis," is found on rocks along the shore as well as on Lamellaria. The name peltoides Carpenter (not of Dall) must be applied to this form.' ORDER CTENOBRANCHIATA Superfamily Toxoglossa Family TEREBRIDAE Shell long, narrow, solid, many whorled, whorls somewhat flattened ; suture shallow; anal fascicle often clearly defined ; aperture relatively small ; anterior canal short, notched ; outer lip sharp ; colum- ella with or without one or two twists or low folds; operculum homy, annular, with terminal nucleus. Geologic range: Cretaceous to Recent. Distribution: Tropical and warm temperate seas, generally in shallow water on fine sandy bottoms. Genus TEREBRA Bruguiere, 1789 Terebra Bruguiere, Encyclo. Meth., Hist. Nat. Vers., Vol. 1, p. XV, genus without species, 1789; Lamarck, Mto. Soc. Hist. Nat. Paris, p. 71, 1799, only species Buccinum subulatutn Linnaeus; Tryon, Man. Conch., Vol. 7, pp. 3-8, 1885; Cossmann, Ess. Pal<;o. Comp., Vol. 2, p. 48, 1896; Dall, Bull. Mus. Comp. Zool., Vol. 43, pp. 245-248, 1908; Woodring, Carnegie Inst., Publ. No. 385, p. 135, 1928. Terebrum Montfort, Conch. Syst., Vol. 2, pp. 430-432, 1810, type Buccinum subulatum Linnaeus. Type (by monotypy, Lamarck, 1799), Buccinum subulatum Linnseus, Syst. Nat., Ed. 12, p. 1205, 1767; Indo-Pacific; Recent. Subgenus TEREBRA, s. s. Shell of large or moderate size, heavy; sculpture generally rather low or absent; columella twisted, often with one or two folds. 1 Carpenter (Mazatlan Catalogue, p. 202) thus describes the Nacella sp. ind. which he later named peltoides: "Tablet 944 contains a solitary specimen of a Nacella, of the shape and size of Ancylus fluviatilis, with the apex spirally recurved, and of a dark horny color. It is not per- fect enough for description." The spirally recurved apex is quite variable. All the Williamias have a spiral apex, and the Pacific coast species generally have the apex recumbent downward or merged in the shell surface. Volume 1 1 PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 465 The typical subgenus is represented on the Pacific coast of North America by Terebra robusta and T. strigata. It appears to be represented in the Miocene of Cahfornia by T. cooperi Anderson' from the Temblor formation, middle Miocene of the Kern River region. Terebra (Terebra) robusta Hinds Terebra robvsta Hinds, Proc. Zool. Soc. London for 1S43, p. 149, June, 1844; Hinds, in Sowerby's Thes. Conch., Vol. 1, Terebra, p. 152, ante Jan. 15, 1845; Reeve, Conch. Icon., Vol. 12, Terebra, pi. 3, fig. 10, 1860; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 11, pi. 2, figs. 16, ? 17, ? 25, 1885; E. K. Jordan, Bull. 8o. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Shell elongated, subulate, turreted, smooth, solid, white, with interrupted longitudinal reddish- brown spots; whorls girdled, but the girdles only visible on the early whorls, the last whorl with three series of markmgs, suddenly eontracted below; aperture elongated, with a short canal; columella arched and covered by a thin callus. Operculum small and thick. Epidermis thicker than is usual. (Hinds, 1845.) Type locality: West coast of America between 8° 57' and 21° 32' north latitude (Hinds). Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Gulf of California, Mexico, to Panama. It is probable that T. loroisi Guerin, not Deshayes, T. incomparabilis Deshayes, T. linguaUs Hinds, and T. insignis Deshayes are either synonyms of or very closely related to T. robusta. References to these species may be found in Tryon's Manual. Terebra robusta Hinds differs from T. strigata Sowerby in the lack of the sinus border- ing the lower margin of the sutural band, or siphonal fasciole, on Hind's species. This linear sinus girdles all the whorls of strigata but can only be detected on the early whorls of robusta. The whorls of robusta are roundly tabulated or shouldered below the suture, which further distinguishes the species from strigata. Hinds reported his species from "Panama, Gulf of Nicoya, Gulf of Papagayo, and San Bias; in from four to eighteen fathoms, sandy mud." Terebra (Terebra) strigata Sowerby Terebra strigata Sowerby, Cat. Shells, TankervUle, Appendix, p. XXIII, 1825; Hinds, Ln Sowerby's Thes. Conch., Vol. 1, p. 151, pi. 41, fig. 10, ante January 15, 1845; Reeve, Conch. Icon., Vol. 12, Terebra, pi. 2, fig. 5, 1860; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 12, pi. 2, fig. 29, 1885; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 206, 1909. Terebra elongata Wood, Index Test., Supplement, p. 55, pi. 13, fig. 25, 1828. Terebra flammea Lesson, lUust. de Zool., pi. 48, 1832, not T.ftammea Lamarck, Hist. Anim. s. Vert., Vol. 7, p. 284, 1822, East Indies. Terebra zebra Kiener, Sp^c. Gen. et Icon. Coq. Viv., Vol. 9, "Genre Vis" (Terebra), p. 5, pi. 3, fig. 5, 1838-39. Type locality: Panama, Recent. Pleistocene: Quaternary deposits at or near Mantua, Ecuador (B. Bryan); Coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Gulf of California and Cape San Lucas to Paita, Peru, and Galapagos Islands (Dall). This species is large and heavy shelled like robusta, but lacks the shoulder on the upper parts of the whorls and has a linear sinus below the suture which is obsolete on robusta. Both species lack sculpture, with the exception of fine growth lines and, on the uppermost whorls, fine axial riblets. In the Stanford University collections there is an incomplete specimen of a fossil Terebra labeled "Terebra strigata Sby. Mantua, Ecuador, Quaternary, B. Bryan," which appears to be correctly identified. ' Proc. Calif. Acad. Sci.. Ser. 3 (Geol.), Vol. 2, p. 203, pi. 16, figs. 66, 67, 1905. 466 San Diego Society or Natural History [ Memoirs Subgenus STRIOTEREBRUM Sacco, 1891 Strioterebrum Sacco, Molluschi dei Terreni Terziarii del Piemonte e della Liguria, Pt. 10, p. 33, 1891; Dall, Nautilus, Vol. 21, p. 249, 1908; Bull. Mus. Comp. Zool., Harvard College, Vol. 43, pp. 246, 248, 1908; Woodring, Car- negie Inst., Publ. No. 385, p. 137, 1928. "Myurella Hinds," Cossmann, Ess. Pal6o. Comp., Vol. 2, p. 49, 1896, not of Hinds, in Sowerby's Thes. Conch., Vol. 1, Terebra, p. 171, 1845. Type (by original designation), Terebra basteroti Nyst; Mediterranean region, Mio- cene. Shell small or medium sized, slender; whorls sculptured with axial ribs and spiral threads or grooves, sutural band generally well defined ; aperture rather narrow, anterior canal short, notched, columella generally with a broad basal fold. Geologic range: Cretaceous to Recent (fide Cossmann, "Myurella"). Distribution : Tropical and warm temperate seas. This group is readily differentiated from the large, heavy, typical Terebras, which generally have no sharply-defined sculpture or have merely rounded nodes or low axial ribs. Strioterebru7n has both axial and spiral ribs; but the spiral ribs are less prominent, generally do not cross the axials, and often are very faint or obsolete. Hinds proposed Myurella^ for the three species which preceded his subgeneric head- ing. It is not surprising that this peculiar arrangement has misled many subsequent authors. Cossmann designated T. affinis Gray as type, a species that followed but was not included in the original list of species. Strioterebrum is well represented on both coasts of Mexico and Central America and also in the Miocene of the Caribbean region and of Panama. Some of the Pacific species are so similar to their Atlantic analogues, even to west African shells, that it is a matter of doubt whether they should be considered distinct varieties. The subgenus is largely tropical in distribution and ranges back at least as far as the Eocene. Terebra (Strioterebrum) variegata Gray Terebra variegata Gray, Proc. Zool. Soc. London for 1834, p. 61, November, 1834; Hinds, in Sowerby's Thes. Conch., Vol. 1, Terebra, p. 173, pi. 43, fig. 53, 1845; Reeve, Conch. Icon., Vol. 12, Terebra, pi. 4, fig. 12 (see also pi. 16, figs. 126, 12c, 12d, V2e), 1860; Tryon, Man. Conch., Ser. 1, Vol. 7, pp. 14, 15, in part, pi. 1, figs. 5, 7, pi. 2, figs. 15, 19, pi. 3, fig. 31, 1885; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. Lower whorls with spiral grooves or cords; sutural band raised, more or less nodulous; body whorl with a Ught peripheral band showing as a white line inside the aperture ; adult shell stout and over 50 mm. m length; color white to bluish gray, with reddish or brownish interrupted spots. (After A. M. Strong, MS.) Type locality: Guaymas, Sonora, Mexico {fide Hinds). Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Sonora coast of Mexico (Hinds); Scammons Lagoon to the Galapagos Islands (Jordan). Terebra variegata Gray is well provided with superfluous names which have been omitted here. For a good discussion of the synonymy the reader is referred to Reeve and to Tryon. The species leans toward Terebra, s. s. 1 Type designated by Dall, Bull. Mus. Comp. Zool., Vol. 43, p. 249, 190S, Terebra myuros Lamarck. Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 467 Terebra (Strioterebrum) specillata Hinds Ten-bra specillata Hinds, Proc. Zool. Soc. London for 1843. p. 15"), June, 1844; Hinds, in Sowerby's Thes. Conch., Vol. 1, Terebra, p. 163, pi. 44, fig. 96, ? pi. 45, fig. 116, January, 1845; Deshayes, Proc. Zool. Soe. London for 1859, p. 303, 1859; Reeve, Conch. Icon., Vol. 12, Terebra, pi. 17, fig. 75, 1860; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 24, pi. 7, fig. 18, 1885; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. ? "Terebra armiUala Hinds," Reeve, Conch. Icon., Vol. 12, pi. 16, fig. 72o only, 1860. Shell slentlerly turreted, very acuminated, whitish, sparingly tessellated with livid flesh color, sutural margin irregularl.v spotted with red, whorls convexly flattened, everywhere latticed with ridges, divided at the upper part by an impressed groove; aperture rather small, columella straight. (Reeve.) Type locality: San Bias, State of Tepic, Mexico. Pleisloce7i.e: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Lower California, Gulf of California, and south to San Bias, Mexico; San Pedro {fide Jordan). Deshayes believed that Hinds' two figures of specillata in the Thesaurus Conchy- liorum probably represent two species, but the present authors are inclined to disagree with this opinion. One of Reeve's figures (72a) of armillata may represent specillata, but without the type specimens themselves it is difficult to separate these closely related forms. They can hardly be more than varietally distinct. Color markings appear to vary as well as sculpture. Some Terebras in the collection at Stanford University from Scam- mons Lagoon, Lower California, Mexico, appear to belong to specillata; but they are of a uniform purplish-blue color, without white bands, and otherwise resemble T. albocincta variety pedroana. T. specillata and its varieties are similar to T. dislocata (Say). Terebra (Strioterebrum) specillata Hinds variety armillata Hinds Terebra armiUala Hinds, Proc. Zool. Soc. London for 1843, p. 154, June, 1844; Hinds, in Sowerby's Thes. Conch., Vol. 1, Terebra, p. 173, pi. 43, fig. 49, 1845; Reeve, Conch. Icon., Vol. 12, Terebra, pi. 16, fig. 72b, ? not fig. 72a, = ? specillata, 1860; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 14, in syn. of rariegata Gray, pi. 2, fig. 21, 1885, reproduction of Reeve's figure 72b,' Dall, Nautilus, Vol. 32, p. 23, 1918. Terebra albicostata Adams and Reeve, Zool. Voy. Samarang, p. 30, pi. 10, fig. 21, May, 1850. Shell subulately turreted, brown or livid, obscurely banded and spotted with rust and white, whorls slopmgly concave, longitudinally irregularly jilicated, s])irall}- ridged and grooved, divided by a groove at the upper part, margin prominent, sometmies strongly obliquely noduled; aperture oblong, columella twistedly recurved. (Reeve.) Type locality: Between Panama and Magdalena Bay, Mexico; Galapagos ?. Pleistocene: Magdalena Bay, Low'cr California, Mexico (Hinds; Dall). Recent: Lower California, Mexico, to Panama; Galapagos ?. Of Reeve's two figures, 72b represents a shell from Panama and 72a looks very much like specillata. The shells from Panama should be considered as coming from the typical habitat of armillata until it can be shown that the Galapagos shell is identical. In regard to habitat. Hinds stated: "Abundant in various localities on the w^est coast of America between Panama and the Bay of Magdalena in Lower California, in from five to thirteen fathoms; also at the Galajjagos, in ten fathoms: chiefly in sandy situations. It was also found imbedded in the fossiliferous cliffs which surround a portion of the Bay of Magdalena." In the collection at Stanford University there are several specimens of Terebra about two inches long reputed to have come from San Pedro that approach in character the com- mon T. dislocata Say from Florida. They have moderately numerous axial ribs and four to six spiral riblets between the anal fasciole and the lower suture. The sutural band is moderately broad, with well-developed, axially elongate nodes. The band is whitish and 468 San Diego Society of Natural History [ Memoirs there is a white band inside the outer hp in the place where the anal fascicle of the next whorl will come. The remainder of the shell is buff colored. One specimen is almost iden- tical with the true dislocata and may be an adventitious specimen. Another has a promi- nent sutural band like armillata. When such apparently anomalous variants occur in a comparatively small series of specimens, it is suggested that it would be beneficial to synonymize a considerable number of supposed specific names and, ignoring the unusual variants, to base those names which have some chance of representing valid distinctions upon the average characters of a large number of specimens. Much more critical study of larger collections than are now available is needed before the true species and varieties of the dislocata clan can be authoritatively described. It is almost certain that there are too many names. Terebra (Strioterebrum) dislocata (Say) Cf. Plate 24, Figure 19 Cerithium dislocalum. Say, Journ. Acad. Nat. Sci. Phila., Vol. 2, p. 235, July, 1822. Terebra rudis Gray, Proc. Zool. Soc. London for 1834, p. 60, 1834. Terebra petitii Kiener, Spec. Gen. et Icon. Coq. Viv., Vol. 9, "Genre Vis" {Terebra), p. 37, pi. 13, fig. 32, 1838-39. Terebra dislocata Say, Tuomey and Holmes, Post-Pleiocene Foss. So. Carolina, p. 70, pi. 11, fig. 12, 1858; Reeve, Conch. Icon., Vol. 12, Terebra, pi. 9, fig. 32, 1860; Tryon, Man. Conch., Ser. 1, Vol. 7, pp. 18, 19, in part, pi. 4, figs. 63-65, 69, 1885. Terebra (Acus) dislocata Say, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 24, 1890. f "Terebra gausapata Brown and Pilsbry," Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 455, pi. 22, figs. 4, 5, 1926, questionably of Brown and Pilsbry, Proc. Acad. Nat. Sci. Phila., Vol. 63, p. 340, pi. 22, figs. 8, 9, 1911, Mio- cene of the Canal Zone. Type locality: Atlantic coast between Maryland and Florida; Recent. Miocene: Virginia, North Carolina, etc. (fide Dall, as dislocata). Pliocene: The Carolinas and Florida, etc. {fule Dall, as dislocata); ? Coyote Mountain, Imperial County, California (Hanna, as gausapata). Pleistocene: "The whole coast from Maryland southward" (Dall, as dislocata) ; ? loc. 249, S. D. S. N. H., lower Pleistocene of Ventura, California (U. S. G.). Recent: Maryland south to Florida; Bahamas and Venezuela (Dall, 1890). We have questionably assigned Hanna's record of Terebra gausapata Brown and Pilsbry, from the Coyote Mountain Pliocene, to T. dislocata Say. In the Oldroyd Col- lection at Stanford University there are specimens of dislocata from the Atlantic coast, some variants of which seem so similar to Hanna's figures of the Coyote Mountain shell that we do not see how they can be reasonably separated. T. gausapata Brown and Pils- bry, according to the type figures, appears to differ from Hanna's specimen in the posses- sion of rounded nodes on the anal fasciole between the upper ends of the axial ribs, not in line with these ribs nor even just slightly offset as on many Recent specimens of the dislocata clan. In 1890 Dall reported T. dislocata from the Miocene to Recent along the Atlantic coast and, as variety tantula Conrad, from the Mississippi Eocene. While this great range might require an unreasonable stretching of the specific limits of the Recent species, it seems that little addition to our knowledge of the group has resulted since that time by the numerous descriptions, as distinct species, of very similar forms based upon an in-, adequate number of specimens. If a long-ranging, warm-temperate form like T. dislocata is known to have lived along the Atlantic coast in the Miocene, when the Atlantic and Pacific were connected, it is not so surprising to find that form in the Pliocene or the Recent of the Pacific coast as well as in the later fossil and Recent record of the Atlantic. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 469 Terebra (Strioterebrum) albocincta (Carpenter) Myurella albocincta Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., pp. 384, 385, 1857. Terehra (Myurella) albocincta Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 258, 1857. Adult shell slender, less than 50 mm. in length ; lower whorls with four or five spiral grooves ; axial ribs distinct on early whorls only; sutural band raised, more or less nodulous; body whorl with a light peripheral band showing as a white Ime inside the aperture; color purplish browni to olivaceous, sutural band whitish. Average measurements: Length, 40 mm.; diameter, 8.5 mm. (After A. M. Strong, MS.) Type locality: Mazatlan, Mexico; Recent. Recent: Gulf of California and west coast of Mexico. T. subnodosa Carpenter is probably a synonym of this species. Terebra (Strioterebrum) albocincta (Carpenter) variety hindsii (Carpenter) Plate 32, Figure 35 Myurella hindsii Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., pp. 385, 386, 1857. "Terebra larvxfortnis Hinds," E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; not of Hinds, 1844. Shell like that of T. albocincta Carpenter, but with the axial ribs obsolete and the spiral grooves strong; color whitish, faintly spotted with reddish brown. Measurements : Length, 31 mm. ; diameter, 7 mm. (After A. M. Strong, MS.) Type locality: Mazatlan, Mexico; Recent. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan, as T. larvseformis Hinds). Recent: Gulf of California, Mexico, to Panama. Mr. A. M. Strong examined the specimen upon which Jordan based his Pleistocene record and pronounced it T. hindsii. It is a doubtfully valid variety of albocincta. As pointed out by Reeve, many of the west African Terebras have characters and variations almost identical with those of species found along the Pacific coast of the Americas. In the absence of a good figure of hindsii, Reeve's figure of T. intertincta Hinds from west Africa might be used for ordinary identifications (Conch. Icon., Vol. 12, Terebra, pi. 16, fig. 12c, 1860). Terebra (Strioterebrum) albocincta (Carpenter) variety pedroana Dall Plate 24, Figures 18, 24 Myurella simplex Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 657, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 395, 1865; Gabb, Geol. Surv. Calif., Pala;o., Vol. 2, p. 78, 1868-69; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 253, 1888; Keep, West Coast Shells, p. 56, fig. 40, 1888, 1892; not of Conrad, 1830. Terebra (Acus) simplex Carpenter, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 207, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 198, 1903. Terebra (Strioterebru7n) pedroana Dall, Bull. Mus. Comp. Zool., Harvard College, VoL 43, p. 251, 1908. Strioterebrum pedroanum Dall, Bull. 112, U. S. Nat. Mus., p. 67, February 24, 1921. Strioterebrum pedroanum philippianum. Dall, Bull. 112, U. S. Nat. Mus., p. 67, 1921, not Terebra philippiana Deshayes, 1859. Terebra (Strioterebrum) pedroana Dall, Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. .59, pi. 6, fig. 6, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Terebra (Strioterebrum) pedroana philippiana Dall, Oldroyd, op. cit., p. 60, 1927. Terebra pedroana Dall, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 252, 1929. Terebra pedroana philippiana Dall, E. K. Jordan, op. cit., p. 245, 1926. Shell like that of T. albocincta (Carpenter), but with the sutural band nodulous on the earlj'^ whorls only ; axial ribs low and distinct or reduced to mere Imes of growth ; color bluish white to yel- lowish browii, irregularly blotched. Size: Length, 32 mm.; diameter, 6.5 mm. (After A. M. Strong, MS.) 470 San Diego yociETY of Natural History [Memoirs Type specimens: Of pedroana and of philippiana, in the U. S. National Museum. Type localities: Of pedroana, San Pedro, California, Recent; of philippiana, new name for simplex Carpenter, Santa Barbara, California, Recent. Pliocene: San Diego well (Dall). Pleistocene: Rare in "Pliocene" of Deadman Island and Tinini's Point, San Pedro; Barlow Canyon, just east of Ventura (Arnold); "Saugus" near Ventura (Waterfall); rare in lower San Pedro series of San Pedro region; foot of Twenty-sixth Street, Spanish Bight, and Pacific Beach, San Diego (Arnold); Spanish Bight, San Diego (F. Stephens); palisades at Santa Monica (coll. by F. C. Clark); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to the Gulf of California, Mexico. The variety philippiana is supposed to be distinguishable from pedroana by its less distinctly develojied axial ribs. Terebra ( Strioterebrum) data Hinds Terebra elata Hinds, Proc. Zool. Soc. London for 1843, p. 156, June, 1844; Hinds, in Sowerby's Thes. Conch., ^'ol. 1, Terebra, p. 177, pi. 44, figs. 68, 69, January, 1845; Reeve, Conch. Icon., Vol. 12, pi. 24, fig. 128, 1860; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 21, pi. 5, fig. 82, 1885. f "Terebra protexta Conrad," Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 456, 1926, questionably of Conrad, 1846. Shell somewhat-like tliat of albocinda, but smaller, with the axial ribs and spiral grooves distmct on all whorls; color reddish white, red banded at base. Size: Length, 25 mm. ; diameter, 5 mm. Type locality: "Bay of Montijo, west coast of America; in fifteen fathoms, coarse sand." (Hinds.) Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Pacific coast of Central America and Panama. Terebra elata Hinds has much more distinct sculpture than T. albocincla and its var- ieties. Generally it is a smaller shell. Hanna's report of Terebra protexta (Conrad)' from the Pliocene of the Carrizo Creek region was based upon a poorly preserved specimen which we suggest may have been T. elata Hinds. The latter is a Recent Central American shell similar to Conrad's species but with a more definitely delimited sutural band. T. protexta ranges from Florida to Vera Cruz,'- Mexico. Terebra (Strioterebrum) elata Hinds variety martini English Terebra martini English, Univ. Calif. Publ. Geol., Vol. 8, p. 216, pi. 23, fig. 3, November 7, 1914. Shell hke that of T. elata Hinds but without spiral sculpture. Type specivien: In the University of California collection. Type locality: Holser Canyon, Los Angeles County; middle Pliocene. Pliocene: Middle Pliocene of Holser Canyon, north of Santa Clara Valley, Los Angeles County, S. D. S. N. H. locality 2l7h (H. R. Gale, collector; type locality, English); San Diego formation at Balboa Park, San Diego (Hertlein and Grant, MS.). This variety is characterized by the numerous, sharp, axial ribs and the absence of spiral striae or threads. The sub-sutural band is prominent. So far as known, it occurs only in the middle Pliocene of the upper Santa Clara Valley and of the San Diego region. It is probably entirely different fioni T. cooperi Anderson, with which English com- pared it. » Cerilhium protextum Conrad, Proc. Acad. Nat. Sci. Phila., Vol. 3, p. 26, February. 1846, "Locality. Tampa Bay?"; Tryon, Man. Conch., Ser. 1, Vol. 7, Terebra, p. 25, pi. 6, fig. 9S, 18S5. 2 F. C. Baker, Proc. Acad. Nat. Sci. Phila. for 1891. p. 49. Volume I 1 PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 471 Family CONIDAE Genus CONUS Linnaeus, 1758 Conus Linnaeus, Syst. Nat., Ed. 10, p. 712, 17.58; Montfort, Coiifhyl. Syst., Vol. 2, p. 406, type cited Comis generalis Linnffius; Children, Quart. Journ. Sci., Lit., Arts, Vol. 16, p. 69, pi. 5, fig. 208, October, 1823, type cited Conus marmoreus Linnseus; Weinkauff, Jahrb. Deutsch. Mai. Gesell., Vol. 1, 1874; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 7, 1884; Cossmann, Ess. Palfe. Comp., Vol. 2, p. 152, 1896; Woodring, Carnegie Inst., Publ. No. 385, p. 201, 1928. Rhombus Montfort, Conchy]. Syst., Vol. 2, \). 402, 1810, type Rhombus impcriaUs = Conns imperinlis Linnaeus. Tijpe (by subsequent designation, Children, 1823), Conus marmoreus Linnaeus, figured by Reeve, Conch. Icon., Vol. 1, Conus, sp. 74, pi. 14, fig. 74, 184.3; Tryon, Man. Conch., 8er. 1, Vol. 6, p. 7, pi. 1, fig. 1, 1884; Indo-Pacific, Recent. Shell heavy, conical, with a very low to moderately elevated spire; aperture long and narrow, nearly or entirely the length of the Ijody whorl; outer lip simple, sometimes sharp; no lirations or denticulations on inner lip; anterior canal a mere siphonal notch; posterior notch very shallow or deep; sculpture generally low or consisting of spiral striations, which are often concentrated on the lower part of the body whorl, and nodes, beads, or blimt spines on the shoulders of the whorls; epi- dermis thin ; operculum with apical nucleus. Geologic range: Cretaceous to Recent. Distribution: Tropical and warm temperate seas. The cones form a very natural and readily recognizable group. Parametaria Dall, of the Pyrenidoe is similar in appearance to Conus, but can be distinguished by the lirations or denticulations on the inside of the outer lip. Parametaria is a small, comparatively rare genus. A number of names have been proposed for subdivisions of Conus, but many of these have very doubtful systematic value. Woodring has concluded that differences of shape and sculpture cannot be used for a satisfactory subdivision of the genus, and he therefore makes use of the characters of the anterior canal, siphonal fasciole, outer lip, and anal fasciole in grouping the cones of the Miocene deposits of Bowden, Jamaica. An attempt to arrange the Recent cones in the Oldroyd Collection at Stanford University by means of these apertural characters seemed unsatisfactory, and we have, therefore, omitted any subgeneric or sectional distinction in listing the fossil cones. It is true, however, that there are several minor groups of Conus which are certainly distinctive and entitled to sectional or subgeneric rank, such as Rollus, Rhombus, and Hermes Montfort,' but they are not represented in the fossil faunas considered in this report. Many Recent species or varieties of Conus have been based largely on color differ- ences, which are nearly always obliterated in fossilization. Fossil specimens not display- ing these color characteristics should be identified with the earliest named species of the region bearing the same morphologic features. In some cases the identity must be purely conjectural. Dall has published a brief paper- on the Recent Pacific coast species of Conus; but his suggested synonymy is not always compatible with the literature, and his later identifica- tions as displayed by museum labels are in part at variance with his published conclusions. ' Conchyl. Syst., Vol. 2. 1810. types, respectively, C geographus Linn^us, C. imperialis Linnseus. and C. mussatellus Linnipus, by original designation. ' Proc. U. S. Nat. Mus.. Vol. 38, pp. 317-228. 1910. 472 San Diego Society of Natural History [Memoirs Conus califomicus Hinds Plate 24, Figure 21 Conus californicus Hinds, Zool. Voy. Sulphur, Vol. 2, p. 7, pi. 1, figs. 3, 4, 5, 1844; Gabb, Geol. Surv. Calif., Palso., Vol. 2, p. 78, 1868-9; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 17, pi. 4, figs. 62, 63, 1884; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 236, 1888; Keep, West Coast Shells, p. 54, 1888, 1892; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 171, 1894; Arnokl, Mem. Calif. Acad. Sci., Vol. 3, p. 199, 1903; Keep, West American Shells, p. 156, fig. 139, 1904; Dall, Proc. U. S. Nat. Mus., Vol. 38, p. 220, 1910; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Dall, Bull. 112, U. S. Nat. Mus., p. 68, pi. 14, fig. 9, 1921 ; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 10, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, no. 7, p. 245, 1926; Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 49, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 61, 1927. Conus ravus Gould, Boston Journ. Nat. Hist., Vol. 6, pp. 386-7, pi. 14, fig. 21, April, 1852; Otia Conch., p. 187, 1862. Shell rather small, pyriform, with a rounded or bluntly angulated shoulder and moderately ele- vated spire ; sculpture consisting of fine spiral threads on the lower part of the body whorl and some- times a few faint striations on the whorls of the spire; livmg specimens of a white or bluish-white color, with or without faint brownish reticulations; periostracum brown. Average adult specimens 30 to 35 mm. in length. Type specimen: Of californicus, in the British Museum ?. Type localities: Of californicus, Magdalena Bay, Lower California, Mexico, "in seven fathoms, on a sandy floor" (Hinds); of ravus Gould, Santa Barbara, California, Recent. Pliocene: San Fernando (Cooper); "Lower Fernando" of Elsmere and Holser canyons, Los Angeles County (English); Fernando Pliocene of Puente Hills, Orange County (Carson, 1926); S. D. S. N. H. loe. 203, one specimen, and 207, eight specimens, both lower Pliocene of Elsmere Canyon, Los Angeles County (H. R. Gale, coll.); S. D. S. N. H. Iocs. 216 and 216a, lower Pliocene east of Fernando Pass, two specimens (H. R. Gale, coll.); S. D. S. N. H. loc. 227, lower Pliocene southwest of Humphreys station, Los Angeles County, several small casts (H. R. Gale, coll.); S. D. S. N. H. Iocs. 217a and 2176, middle Pliocene near Holser Canyon, Los Angeles County, two small specimens (H. R. Gale, coll.) ; S. D. S. N. H. loc. 221, middle Pliocene east of Canada de Aliso, Ventura County, one speci- men (H. R. Gale, coll.); S. D. S. N. H. loc. 222, middle Pliocene at head of Canada de las Encinas, Ventura County, one specimen (H. R. Gale, coll.); S. D. S. N. H. loc. 219, Sexton Canyon shale, upper Pliocene, Ventura County ; upper Pliocene of Deadman Island and Timm's Point, Los Angeles County (Arnold, 1903). Pleistocene: Lower San Pedro series at Deadman Island and San Pedro (Arnold); lower Quaternary at Mag- dalena Bay, Lower California, Mexico (E. K. Jordan); lower Sim Pedro fauna of Nob Hill cut, San Pedro, "plentiful" (T. S. Oldroyd); S. D. S. N. H. loc. 242, Adams Canyon, Ventura County; L. S. J. U. loc. 275, two miles north-northeast of Santa Paula, Ventura County; L. S. J. U. loc. 237, "Saugus" Pleistocene of Adams Canyon, Ventura County; Pleistocene of Spanish Bight and Pacific Beach, San Diego County; upper San Pedro series at Deadman Island, Crawfish George's, Los Cer- ritos, San Pedro, and Long Beach, Los Angeles County, common (R. Arnold, 1903); upper Pleisto- cene of San Quintin Bay, Lower California, Me.xico (E. K. Jordan, 1926). Recent: Farallone Islands, California, to Ballenas Lagoon, Lower California, Mexico (Dall). This, the only species of Conus in the Recent fauna of California, is recognizable by its lack of prominent sculpture, its rounded shoulder, and its small size. The anterior canal is slightly curved backward, producing a somewhat constricted appearance near the base of the body whorl. The variety /ossi7is T. S. Oldroyd is larger and has a higher spire, but is probably not of significance. Conus califomicus Hinds variety fossilis T. S. Oldroyd Conus californicus fossilis T. S. Oldroyd, Nautilus, Vol. 34, no. 4, p. 116, pi. 5, fig. 9, April, 1921 ; Proc. U. S. Nat. Mus., Vol. 65, p. 10, 1924. Type specimen: In the Oldroyd Collection, Stanford University. Type locality: Nob Hill, San Pedro, Los Angeles County; lower Pleistocene. Pleistocene: Lower and upper San Pedro beds of San Pedro region, Los Angeles County (Oldroyd) ; Pleistocene of Spanish Bight, San Diego County (Mrs. Kate Stephens MS.). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 473 This form differs from the typical in the more elongate shape and greater proportion- ate distance between the shoulder of the body whorl and the apex of the spire. It occurs in the Pleistocene, where it is less common than the normal form with which it appears to intergrade. Some Recent specimens appear to agree in characters with fossilis, and it is almost certain that the form fossilis is represented merely by unusually healthy or aged individuals of the normal form and that therefore the name should be synonymized. Conus fergusoni Sowerby ? ('onus coelebs Hinds, Ann. Mag. Nat. Hist., p. 256, 1843, fide Dall, 1910. f Conus hayiensis Sowerby, Quart. Journ. Geol. Soc. London, Vol. 6, p. 44, 18.50, fide Hanna, 1926. Conus fergusoni Sowerby, Proc. Zool. Soc. London for 1875, p. 145, pi. 15, fig. 1; Tryon, Man. Coneh., Ser. 1, Vol. 6, p. 15, pi. 4, fig. 52a, 1884; Stearns, Proe. U. S. Nat. Mus., Vol. 16, p. 386, 1893; Dall, Vol. 37, p. 207, 1909; Vol. 38, p. 218, 1910; Dall, Nautilus, Vol. 32, p. 23, 1918; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 446, pi. 21, figs. 6, 7, 1926. ? Conus mollis Brown and Pilsbry, Proc. Acad. Nat. Sci. Phila., p. 343, pi. 23, fig. 1, 1911. Type locality: Panama, Recent. Miocene: ? Pliocene: Imperial formation. Coyote Mountain, Imperial County, California (Hanna). Pleistocene: Magdalena Bay, Lower California, Me.xico (Dall, 1918). Recent: Magdalena Bay, Lower California, Mexico, to Ecuador and Galapagos Islands (Dall, 1910). This is a large, white species, rather broad at the shoulder and lacking conspicuous sculpture. The width at the shoulder is three-fifths or more of the axial length. The spire is low. Should C. coelebs Hinds, 1843, be proved to be the young of C. fergusoni, as suggested by Dall, the later name will become a synonym. Hanna has pointed out the possibility of C. hayiensis Sowerby and C. mollis Brown and Pilsbry being conspecific with fergusoni. C. rnollis occurs in the Gatun formation, middle Miocene of Panama. Conus gladiator Broderip Conus gladiator Broderip, Proc. Zool. Soc. London, p. 55, 1833; Reeve, Conch. Icon., Vol. 1, Conus, sp. 127, 1843; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 28, pi. 8, fig. 38, 1884; Stearns, Proc. U. S. Nat. Mus., Vol. 16, p. 386, 1893 (erroneously as of Sowerby) ; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 170, 1894; Dall, Vol. 38, p. 221, 1910. "Spire rather depressed, tuberculate, and striate; color chocolate-brown, variegated with white, disposed in longitudinal streaks, with an irregular white band, and more or less distinct revolving lines of darker brown; interior white or tinged with chocolate; epidermis fibrous. Length, 1.25-1.75 inches." (Tryon.) Pleistocene: Upper Pleistocene of the coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Gulf of California to the Galapagos Islands (Dall). This species appears to be very closely related to C. hrunneus Gray,' from which it is said to differ by the finer coronation on the upper portion of the shell. Conus lucidus Mawe in Wood Conus lucidus Mawe, Wood's Index Test., Suppl., pi. 3, fig. 4, 1S28; Stearns, Proc. U. S. Nat. Mus., Vol. 16, p. 385, 1893; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 207, 1909; Vol. 38, p. 226, 1910; Dall, Nautilus, Vol. 32, p. 23, 1918. Conus reticidatus Sowerby, Conch. lUust., Conns, p. 3, part and plate 57, fig. 86, 1833; not Conus reticulatus Martini, Neues Syst. Conch. Cab., Vol. 2, p. 261, pi. .56, figs. 619-621, 1773. "Conus puncticulatus Hwass" E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; not of Hwass, 1792. ' Wood's Index Test., Supplement, pi. 3, fig. 1, 1828. Some of the names were taken from the MSS. of John E. Gray, fide "Catalogue of the Books, Manuscripts, Maps and Drawings in the British Museum (Natural History),'* Vol. 5, p. 2353, 1915. 474 San Diego Society of Natural History [ Memoirs Pleistocene: Lower Quaternary of Magdalena Bay, Lower California, Mexico (Dall, 1918; one specimen in the collection at Stanford Univ.) ; upper Pleistocene, coast of Oaxaca, Mexico (coll. by R. H. Palmer). Beccnl: Magdalena Bay, Lower California, Mexico, to the Galapagos Islands (Dall, 1910). This is a rather short, broad species with low, evenly conical spire and handsome brown, reticulated color markings on a white background. Sculpture is practically absent. Conus reticulahis Sowerby, 1833, is unquestionably conspecific. In the Stanford col- lections there is one specimen labeled Conus puncticulaius Hwass from the Quaternary of Magdalena Bay which retains faintly the color markings of C. lucidus. According to Dall, Conus puncticulaius Hwass was distinctly assigned to the West Indies by the original describer, and west Mexican specimens assigned to puncticulatus by other authors Dall refers to Conus complus Gould, 1851, an identification that is puzzling if the habitat (Santa Barbara) given by Gould is correct. Conus mahogani Reeve Conus interruptiis Broderip and Sowerby, Zool. Journ., Vol. 4, p. .379, 1829; not C. interruplus Mawe, 182S. Conus mahogani Reeve, Conch. Icon., Vol. 1, Conus, sn. 126, pi. 22, fig. 126, Aug., 1843; Proe. Zool. Soc. London for 1843, p. 169, 1844; Dall, Proc. U. S. Nat. Mus., Vol. 38, p. 219, 1910. Conus interruplus Broderip, Tryon, Man. Conch., Ser. 1, Vol. 6, p. 63 (in part), pi. 27, fig. 8, 1884. "Shell clongately turbinated, rather cylindrical, grooved towards the base; whitish, profusely stained with red- dish brown and encircled with numerous fillets of the same color articulated with white; spire very much raised; in- terior white." (Reeve.) Type localities: Of C. mahogani Reeve, Salango, West Colombia; of C. interruptus Broderip and Sowerby, near Mazatlan. Pleistocene: Upper Pleistocene, west coast of Oaxaca, Mexico, on the Gulf of California (coll. by R. H. Palmer). Recent: Magdalena Bay, Lower California, Mexico, to Panama. C. catenatus Sowerby, 1878, may be a variety of this species. The specific name is preoccupied by C. catenatus Sowerby, 1850,^ but until the west coast species of Conus are thoroughly reviewed, additional names are more of a hindrance than a help. Conus purpurascens Broderip Conus purpurascens Broderip, Proc. Zool. Soc. London for 1833, p. 54; Stearns, Proc. U. S. Nat. Mus., Vol. 16, p. 387, 1893; Vol. 17, p. 170, 1894; Dall, Vol. 37, p. 207, 1919; Vol. 38, p. 219, 1910; Nautilus, Vol. 32, p. 23, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sei., Vol. 23, p. 149, 1924. Type locality: Panama, Recent. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Dall, 1918; Jordan, 1924); upper Pleistocene, coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Magdalena Bay, Lower California, Mexico, and the Gulf of California to Paita, Peru. This is a moderately large cone, with a rather low, conical spire. The body whorl is widest just below the shoulder. The sculpture consists of strong growth lines and low, widely spaced, spiral threads on the lower part of the body whorl, becoming obsolete near the middle. The color of Recent specimens is a purple mixed with brown, maculated with white or light pink. It is quite variable in its coloring and markings. Specimens 80 or 90 mm. in length are common. 1 Quart, Journ. Geol. Soc. London, Vol. 6, p. 4.5, pi. 9. fig. 2, 1850, Caribbean Miocene, fide W'oodring, Carnegie Inst., Publ. No. 385, pp. 213, 214. 1928. Volume I ] PLIOCENE AND PLEISTOCENE AIOLLUSCA OF CALIFORNIA 475 Conus planiliratus Sowerby Conus planiliratus Sowerby, Quart. Journ. Geol. Soc. London, Vol. 6, p. 44, 1850; Hanna, Proc. Calif. Acad. Sei., Ser. 4, Vol. 14, p. 447, 1926; Woodring, Carnegie Inst., Publ. No. 385, p. 210, pi. 10, figs. 7, 8, 9, pi. 11, fig.s. 1, 2, 1928. Not Co7ius planiliratus Sowerby, Proc. Zool. Soc. London for 1870, p. 255, = C. maculospira Pilsbry, Proc. Acad. Nat. Sci. Phila., Vol. 73, p. 329, 1922, new name. ,' Conus stimpsoni Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 503, pi. 29, fig. 7, 1902. Type specimen: Of planiliratus, in the British Museum, fide Woodring. Type locality: Dominican Republic, Miocene. Miocene: Middle Miocene of the Dominican Republic; Gatun formation (middle Miocene) of Panama and Costa Rica (Woodring, 1928). Pliocene: Limon, Costa Rica (Woodring); ? Pliocene of Coyote Mountain, in a branch of Alverson Canyon, Imperial County (identified questionably by Hanna). f Recent: As "Conus stimpsoni" Dall, off Key West, Florida. This species has been well figured and described by Woodring. The spiral sculpture which may be either strap-like or consist of rather widely spaced rounded cords is char- acteristic. Hanna, working with poorly preserved material from the Imperial formation of western Imperial County (Pliocene), questionably identified some specimens of Conus with this species. Conus stimpsoni Dall is either conspecific with C. planiliratus Sowerby, 1850, or very closely related, as indicated by Woodring. Conus princeps Linnseus Conus princeps Linnaeus, Syst. Nat., Ed. lU, p. 713, 1758; liceve. Conch. Icon., Vol. 1, Conus, sp. 36a, pi. 7, fig. 36a, 1843; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 29, pi. 8, fig. 42, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 207, 1909; Vol. 38, p. 224, 1910. Conus regius Chemnitz, Neues Syst. Conch. Cab., Vol. 10, p. 15, pi. 138, fig. 1276, 1788. Pleistocene: Coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Cape San Lucas, Lower California, Mexico, to Panama (Dall, 1910) and south to Paita, Peru (Dall, 1909). This is a handsome, low-spired species, of a pinkish or orange ground color with wavy, irregular dark brown axial lines. The shoulder of the body whorl and the whorls of the spire have rather evenly-spaced, low, rounded nodosities. According to Dall, Conus lineolatus Valenciennes' is the variety with the axial stripes reduced to brown hair lines. The variety without the axial stripes Dall has named apogrammatus.^ In the Stanford collections there is one small cone from the Pleistocene along the coast of Oaxaca, Mexico, collected by R. H. Palmer, which appears to belong to this species. Conus scalaris Valenciennes Convs scalaris Valenciennes, Voy. Reg. fiquinox. Nouv. Cont., Humboldt et Bonpland, Pt. 2, Zool., Vol. 2, liv. 14, p. .338, 1832; Sowerby, Thes. Conch., Vol. 3, Conus, p. 14, pi. 9, fig. 192, 1S57; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 35, pi. 10, fig. 83, 1884; Dall, Proc. U. S. Nat. Mus., Vol. .38, p. 221, 1910; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, it. 5, p. 154, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. 1 Voyage aux Regions Equinoxiales du Nouveau Continent, fait en 1799-1804, etc., by F. H. A. von Humboldt and A. J. A. Bonpland. Atlases and 24 vols, (of the complete work), 4° and folio. Paris. 1805-37; Part 2, Zoology, Vol. 2, Coquilles, by A. Valenciennes. Conus lineolatus Valenciennes is presumably described on pp. .336-7 of Vol. 2, liv. 14, issued in 1832. We have not seen this work. For brief colla- tion and dates of issue of the various livraisons of the "Observations de Zoologie," see the note by C. Davies Sherborn, Ann. and Mag. Nat. Hist., Ser. 7, Vol. 3, no. 17, p. 428, May, 1899. ' Proc. U. S. Nat. Mus., Vol. 38, p. 224, 1910. type locality, Panama. Reeve, Conch. Icon., Vol. 1, Conus. pi. 7, fig. 36f, represents this variety. Variety lineolatus is represented by fig. 366. Conus regius Chemnitz, as figured by that author, is nearest to Reeve's fig. 36a. We have not seen Valenciennes' description nor figure. 476 San Diego Society of Natural History [Memoirs "Spire elevated, gradate, maculated with chestnut; body whorl somewhat acuminate below; yellowish white with brown-chestnut longitudinal strigations, scarcely interrupted for a narrow central white band, and replaced towards the base by a few revolving rows of chestnut markings. Length 3 inches." (Tryon.) Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Scammons Lagoon and Cedros Island, Lower California, to Gulf of California, Me.xico. Tryon figures a shell with a very sharply defined shoulder and an elevated, sub- turreted spire. His figure is taken from Sowerby. We have not had access to the original description. Conus regularis Sowerby is certainly very close to C. scalaris Valenciennes and may prove to be conspecific. Conus regularis Sowerby Conus regularis Sowerby, Conch. Illust., Conus, p. 2, part and pi. 36, fig. 45, 1841; Thes. Conch., Vol. 3, Conus, pp. 16, 17, pi. 9, figs. 208-210, 1857; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 37 (in part), pi. 11, figs. 99, 100, 1884; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 171, 1894; Dall, Vol. 38, pp. 221, 222, 1910; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 154, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 447, pi. 21, fig. 8, 1926; Jordan and Hertlein, Vol. 15, p. 419, "Conus aff. C. regularis Sowerby," 1926; Hanna and Hertlein, Vol. 16, p. 142, 1927. ? "Conus recurvus Brod." Kiener, Spec. Gen. et Icon. Coq., Vol. 2, Conus, pi. 97, figs. 4, 4a, 1845-46; p. 132, 1847. Conus beali Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 49, pi. 11, fig. 2, 1926. Shell moderately elongate; spire elevated, subturreted, anal fasciole slightly concave, ascending at the suture on previous whorl; body whorl elongate, profile not quite rectilinear, a very slight con- vexity above the middle and a very slight constriction toward the base; shoulder abruptly rounded; sculpture consistmg of very low, closely and evenly spaced spiral cords on the basal portion of the body whorl, lacking on the shoulder and spire. (Height of the type of C. beali Carson, 64 mm. in- complete; width, 32 mm.) Type specimen: Of beali, in the type collection at Stanford University. Pliocene: Lower (or middle) Pliocene of the Pucnte Hills, Orange County, California (Carson; type loeaUty of "Conus beali"); (?) Imperial formation, Imperial County, California (G. D. Hanna); Coronados Island and Carmen Island, Gulf of California, Mexico (Hanna and Hertlein) ; ? Elephant Mesa, near Turtle Bay (south of Scammons Lagoon), Lower California, Mexico (Jordan and Hertlein, as "Conus aff. 0. regularis Sowerby"). Pleistocene: Coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Scammons Lagoon, Lower California, and the Gulf of California, Mexico, to Panama. This species, as figured by Sowerby in the Conchological Illustrations, is a shell of medium size with a nearly rectilinear body-whorl profile, a moderate spire, which is con- cave in profile and somewhat turreted, and a color pattern consisting of dark brown or chocolate maculations on a white or light brown ground, the arrangement of the macula- tions being spiral with vertical interruptions. Specimens in the Oldroyd Collection at Stanford University from the Gulf of California agree well with Sowerby's figure. A speci- men of average size has the following measurements: length, 51 mm.; width, 27 mm.; height of spire from shoulder of body whorl, 12 mm. It is quite possible that Conus regularis Sowerby is conspecific with C. scalaris Valen- ciennes, but not having the original description of the latter species, we hesitate to make any change. The "Conus recurvus Brod." of Kiener is very close and may be a synonym. Conus beali Carson is inseparable from large Recent specimens of regularis, and is a very close synonym. Carson called attention to the occurrence of this warm-water species in the Puente Hills Pliocene. Conus floridanus Gabb* is the Atlantic analogue of C. regularis. 1 Amer. Journ. Conch., Vol. 4, p. 195. pi. 15, fig. 4, 186S; Recent range from Florida to Cape Hatteras; Pliocene of Florida, fiile Dall. Trans. Wagner Inst. Sci., Vol. 3, p. 27, 1890. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 477 The specimen from the Pliocene of Coyote Mountain, figured by Hanna, appears to have a much lower spire and more rounded shoulder on the body whorl than any varia- tions of Recent Conus regularis we have seen. It is certainly far from typical and may belong to a different species. Conus tomatus Broderip Comts tornalus Broderip, Proc. Zool. Soc. London for 1833, p. 53, 1833; Sowerby, Conch. Illust., Conus, p. 2, part and pi. 29, fig. 25, 1833; Reeve, Conch. Icon., Vol. 1, Conus, sp. 68, pi. 13, fig. 68, 1843; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 63 (in part; in syn. of C. iuh-rruplus Brod.), pi. 20, fig. 4, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 207, 1909; Vol. 38, p. 219, 1910; Nautilus, Vol. 32, p. 23, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 1918; E. K. Jordan). Recent: Cedros Island, Lower California, the Gulf of California, Mexico, south to Ecuador. This species has a high, turreted spire, which, according to Reeve, distinguishes it from C. interruptus Broderip (not Mawe). It appears to have a more elongate body whorl than C. arcuatus Sowerby. The latter species has a strongly curved outer lip, with a deep anal notch. Conus ximines Gray Conus ximines Gray, Zool. Beechey's Voyage, p. 119, pi. 33, fig. 2, 1839; Tryon, Man. Conch., Ser. 1, Vol. 6, p. 63 (as synonym of C. interruptus Broderip), pi. 19, fig. 100, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 207, 1909; Vol. 38, p. 220, 1910; Dall, Nautilus, Vol. 32, p. 23, 1918. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 1918). Recent: Gulf of California, Mexico, to Seehura Bay, Peru. Conrad considered Conus ximines Gray a synonym of C. interruptus Broderip, and this latter species, according to Dall, is a synonym of Conus mahogani Reeve. Dall, how- ever, in his 1910 paper, retains ximines as valid. We have not seen the original descrip- tion nor authentic specimens of this species. Conus vittatus Hwass Conus vittatus Hwass, Encycl. Mcth., Hist. Nat. Vers, Vol. 1, Genus Conus, p. 704, 1792; Reeve, Conch. Icon., Vol. 1, Conus, sp. 75, pi. 14, figs. 75a, 75b, 1843; Kiener, Sp6e. G(5n. et Icon. Coq., Vol. 2, Conus, pi. 63, fig. 5, 1845-46; p. 110, 1847; Dall, Proc. U. S. Nat. Mus., Vol. 38, p. 221, 1910; Nautilus, Vol. 32, p. 23, 1918. ? Conus henoquei Bernhardi, Journ. Conchyl., Vol. 8, p. 380, pi. 13, fig. 4, 1860, fide Dall, 1910. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 1918). Recent: Acapulco, Mexico, to Panama. We have not .seen authentic specimens of this species. Family TURRIDAE (+ PLEUROTOMIDAE; also TURRITIDAE) Shells of various shapes and sizes, usually distinguished by a posterior notch, slit, or sinus near the top of the outer lip. The typical genera are of medium size, fusiform in general shape, turreted or round-whorled, operculate; but many of the other common genera have high conical spires and short anterior canals, and some of the deep-water forms are small, thin-shelled, inoperculate. Geologic range: Cretaceous to Recent. 478 San Diego Society of Natural History [Memoirs Important references for the family are as follows : Iviener, Sp^c. G&. et Icon, des Coq. Viv., Vol. 5, Pleurotome, 81 pp., 27 pis., Paris, 1839-40. Reeve, Conch. Icon., Vol. 1, Pleuroloma, 40 pis. with descriptions, 1843-46; Vol. 3, Mangelia, 8 pis. with descriptions, 1846. Bellardi, "Mon. Pleur.," R. Accad. delle Scienze di Torino, Memorie, Ser. 2, Vol. 9, pp. 531-650, pis. 1-4, (1847) 1848. H. and A. Adams, Gen. Rec. Moll., Vol. 1, pp. 87-100 (Vol, 2, p. 614) ill., London, 1853. Bellardi, "Prodromus," Bollettino della Societa Malacologica Italiana (Pisa), Vol. 1, pp. 16-24, 1875. Weinkauff, Deutsche Malakozoologische Gesellschaft (Frankfurt-am-Main), Jahrbuch, Vol. 3, 1876; Vol. 4, 1877. Bellardi, Moll. Tert. do Piemonte, Pt. 2, R. Accad. della Scienze di Torino, Memorie, Ser. 2, Vol. 29, pp. 1-324, pis. 1-9, (1877) 1878. Tryon, Struct, and Syst. Conch. (Vol. 1, p. 50), Vol. 2, pp. 183-186, Philadelphia, 1883. Fischer, Man. Conchyl., pp. 589-594, ill., Paris, 1883. Tryon, Man. Conch., Vol. 6, pp. 151-413, 34 pis., Philadelphia, 1884. Monterosato, Nomen. Gen. Spec. Conch. Medit., pp. 126-137, Palermo, 1884. Wemkauff (and Kobelt), Syst. Conchyl. Cab., N. S., Vol. 4, Pt. 3, 248 pp., 43 pis., Niirnberg, (1875—) 1887. Dall, Bull. Mus. Comp. Zool., Harvard College, Vol. 18, pp. 71-128, ill., 1889. Boettger, Deutsche Malakozoologische Gesellschaft (Frankfurt-am-Main), Nachrichtsblatt, 1895. Cossmann, Ess. de Palto. Comp., Vol. 2, pp. 56-148, ill., 1896. Harris, Cat. Tert. Moll. Brit. Mus., Pt. 1, pp. 37-65, ill., London, 1897. Casey, Trans. Acad. Sci., St. Louis, Vol. 14, no. 5, pp. 123-170, 1904. Cossmann, Ess. de Paleo. Comp., Vol. 7, pp. 218-224, ill., 1906. DaU, Bull. Mus. Comp. Zool., Harvard College, Vol. 43, pp. 255-293, ill., 1908. DaU, Proc. V. S. Nat. Mus., Vol. 54, pp. 313-333, 1918; Vol. 56, pp. 1-86, pis. 1-24, 1919. Hedley, Rec. Australian Mus., Vol. 13, no. 6, pp. 213-359, pis. 42-56, 1922. Thiele, Deutsche Tief see-Expedition, Wissenschaftliche Ergebnsse, Vol. 17, Pt. 2, Gastropoda, pp. 202-256, ill., 1925, includes descriptions of radulae. Woodring, Carnegie Inst. Wash., Publ. No. 385, pp. 144-201, 1928. Nearly everyone who has had occasion to write about the Turridce has mentioned in one way or another the unsatisfactory state of the classification, the chaotic condition of the nomenclature with its vast store of superfluous names, and the great difficulty of grouping the shells in a natural order. The writers have found it impossible at the present time to do more toward straightening out the confusion that prevails in this family than to point out some of the more evident changes in nomenclature required by the applica- tion of the modern rules, and to suggest a makeshift classification based mainly upon ob- servable shell characters so that the species here noted will find at least a temporary rest- ing place. It is hoped that this classification will be more logical, more natural, more nearly in accord with the phylogenetic relationships than those hitherto proposed; but it is clear that a great deal more study and more detailed observation on large series of fossil and living shells in all stages of growth, and on living animals, will be necessary before a thoroughly satisfactory arrangement can be expected. Fischer's classification, which has been followed with various modifications by many of the later workers, is based primarily on the form of the operculum. The operculum may have a terminal nucleus as in Turris, or a nucleus situated near the center of the left side as in Clavatula, or a paucispiral, subcentral nucleus as in Steiraxis, or it may be entirely lack- ing as in Mangelia. Although it is perfectly reasonable to take account of the nature of the operculum (where possible) as one of the characters of a species or genus, like its size, shape, or ornamentation, it seems not unlikely that the disproportionate emphasis placed on this single character is responsible for part of the difficulty experienced in dealing with the family. In other families it is recognized that related genera, that related species in the same genus, that even individuals in the same species may differ as to the shape or as to the presence or absence of their opercula, and that sometimes if an individual lose its operculum it may grow one of a different shape in its place. Thiele relies principally on Volume I ] PlIOCENE AND PLEISTOCENE MoLLXJSCA OF CALIFORNIA 479 the radulse for his classification, paying some attention to the opercula, but apparently re- garding the shell characters as of very subordinate importance. He would separate the operculate members of the family, with the exception of the forms formerly called Bela, here referred to Lora, into a new superfamily, Pseudotoxoglossa, because these forms have in their radulse a continuous membrane into which the teeth are set in regular rows as in other normal gastropods. Although Thiele's contribution of descriptions and illustra- tions of previously unknown radulse is surely of considerable importance, it is hard to jus- ify his faith in the supreme value of one part for classification. It is true that radulse have been used as the basis for separating other large groups of gastropods ; but the classi- fication of gastropods is still only tentative, and it may not be amiss to wonder whether the widespread faith in the value of the most inaccessible parts of the animal is not entirely due to the comparatively limited knowledge of them. Other characters which are appar- ently distinct when studied in isolated individuals have been found in large series to pass through insensible gradations from one extreme to another, and it is hardly to be expected that comparable variability will not be found in all characters, that now one and now another will be a more reliable clew to phylogeny. In the case of the Titn-idce the presumption is against the value of opercula and radulse for classification, for they point to nothing with the ear-marks of order, tending merely to confuse by separating into widely different groups genera which are shown by their other characters to form links in a normal intergrading series; and they are some- times contradictory, as in the case of anomalous forms like the genus Lora, which the radula would classify with the inoperculate group and the operculum would classify with the "Pseudotoxoglossa." It is not at all certain that the different radulse and opercula are not the result of generic or even specific adaptation to environment, and that the latter may not be a secondary feature dependent upon the shape of the shell aperture. The larg- er sized genera like Turricula, Clavatula, Claims and Surculites are represented by very similar forms in the Cretaceous, whereas representatives of the smaller, thinner genera are not known until later, either because they were less suited for preservation or because they evolved later. It would be natural for the larger forms when adapting themselves to colder or deeper waters or other specialized conditions to develop smaller, thinner shells and at the same time to lose the need of opercula and of stiffening membranes in the radula. The evolution might affect different parts at different rates in different lines of descent so that Lora lost its membrane before its operculum and Genota lost its operculum before its membrane, and Leucosyrinx retained both and just grew thin. If such is the case, some of the branches of the small inoperculate group may be more closely related to the particular branches of the large operculate group from which they were derived than they are to each other, and they should not be separated as a different family, sub- family, or superfamily. At other times, the protoconchs or embryonic whorls have been appealed to as a basis for classification, some writers going so far as to bring together very unlike species because they have similar protoconchs and to separate otherwise similar species because their protoconchs differ. In regard to this matter also, it seems wise to take careful note of the protoconchs (where possible) , but in most cases not to rely upon them when they contra- dict the evidence afforded by other characters. It is well to recognize that the significance of protoconchs is still very imperfectly understood, that the protoconchs of few species are accurately known, that even on living specimens the protoconchs are seldom preserved in the adult, that if preserved, erosion may entirely alter their aspect, and that in the Buccinidce and other groups where the embryonic shells can be collected from the egg 480 San Diego Society of Natural History [Memoirs capsules of individual specimens it has been observed that several different kinds of proto- conchs are present as offspring of the same parents. Sometimes the characters of the protoconchs may be due to an acceleration of the time of the development of the adult characters, in which case they would not necessarily indicate genetic relationships ; and in some cases the form of the protoconch may be determined by the environment through natural selection, being perhaps as late in phylogenetic development as the adult char- acters. In other words, it is best to pin our faith not upon characters rarely observable and very imperfectly understood but upon characters the development of which can be seen and traced, upon specific relationships as shown by the intergrading or close approach of similar variations, taking into account all observable characters. In this connection, the following quotation from Dall is appropriate: "In common with most students of the mollusca for some years I have regarded the nucleus characters as more or less indicative of genetic affinity, but recently having had to work over large numbers of deep water species, espe- cially toxoglossate forms, and to utilize Hedley's fine monograph of the Australian Turridae, I have found this view to involve so many apparently preposterous combinations of unlike things and separation of similar things, that I have come to the conclusion that this view cannot be maintained."' The accompanying diagram, in the form of a horizontal cross section of the Turrid family tree, shows what the writers believe to be in general the natural relations of the family. It is an attempt to represent graphically the interrelations between the various genera that are described in the text so that the arrangement may be better visualized. Each genus is enclosed by a line, and when adjacent genera intergrade and are difficult to distinguish, the lines overlap. These intergradations are not in simple series but in complicated irregular patterns, the overlapping sometimes occurring in many directions, sometimes in directions that are hard to explain. It has been possible to show in this fashion nearly all of the intergradations that the writers have recognized, though too much cannot be expected of a two-dimension diagram of such a subject as this, which if all the facts were known would require a many-dimension diagram to represent it adequately. Many vertical sections would be necessary to show the genetic series; and there is not enough information at hand to make it worth while to try to draw them now. The development of the groups indicated must be imagined somewhat as the hanging branches of a vine, each one with forks and side branches and numerous radiating fronds; and if such a vine were lowered into a still pool of water the various branches would cause circu- lar ripples somewhat Uke the lines drawn in the diagram. As explained below, the form most like the ancient radicle from which the vine grew is probably the subgenus Knefasiia of Clavatula, sensu lato. The main Clavus branch is fairly distinct. The Borsonia, Turris, Leucosyrinx, and Surculites branches all have something in common with the ancient Turricula stock, and probably developed either through Turricula or parallel to it. Several other families show evidence that they are more or less closely related to the Turridce. The Conidos, for instance, have a toxoglossate radula, a small horny operculum which is sometimes present, sometimes absent, and often a posterior sinus at the top of the body whorl. They are however, easily distinguishable by their low spire and conical shape and by their habit of partially resorbing the interior walls of the spire whorls. The TerebridcE have a toxoglossate radula, an anal fasciole or slit band, though no posterior sinus, and are resembled by Pusionella and Melatoma. They are distinguished by their high, many-whorled conical spire, and short, twisted columella. The radulae of these two families are apparently more extreme than those of the Turridce, for in the Turridce not ' Journ. Wash. Acad. Sci., Vol. 14. p. 178, 1924. Volume I ] Pliocene and Pleistocene Mollusca of California 481 < a O Z O I to in O « O Z O SI s o 482 San Diego Society of Natural History [ Memoirs all of the forms have yet become toxoglossate. The Pyrenidoe have a rachiglossate radula, like that of the "Pseudotoxoglossa" branch of the Turridce, and often resemble the Conidce or the Turridce in shape. The posterior flare or canal at the top of the outer lip which is often so conspicuous in the Pyrenidoe has probably the same function as the sinus that characterizes the other two families. Some species and varieties of the smaller genera, like Anachis and Cythara or MangeUa, Amphissa and Lora, in which the flare or sinus may be obscure, are often very difficult to distinguish. The similarity may be due entirely to parallel adaptation to similar environments, but it seems probable that the families are more closely related than is generally admitted. The rachiglossate Volutidce are related through the Cretaceous Drilluta Wade, and the Mitridce through the Tertiary Scobinella Conrad and possibly through the Tertiary to Recent Mitromorpha. Some of the fossils are very difficult to distinguish. Lastly, the more ornate species of Turricula, Clavatula, and Clathrodrillia often resemble Fasciolariidce, Neptuneidce, etc. In nearly all cases the Turridce can be distinguished from the members of other families by the posterior sinus ; and even in specimens where the aperture is defective, the sinus is usually recognizable as an incurving of the growth lines. Genus CLAVATULA Lamarck, 1801 Clavatula Lamarck, Syst. Anim. s. Vert., p. 84, 1801; Cossmann, Ess. Pal^o. Comp., Vol. 2, p. 65, 1896; Dall, Proc. II. S. Nat. Mus., Vol. 54, p. 315, 1918; Thiele, Wiss. Erg. Deutsch. Tiefsee-Exped., Vol. 17, pp. 204, 205, 207, 1925. Not "Clavatula Lamarck," Swainson, Treat. Malac, pp. 155, 314, 1840, sole species C. sulcata Swainson, Chemnitz fig. 1829 = Pleurotoma flavidula Lamarck, a Clavus {Clathrodrillia). Type (by monotypy), Clavatula coronata (Chemnitz) Lamarck, 1801 = Murex {Tur- ris) coronata Chemnitz, Neues Syst. Conchyl. Cab., Vol. 11, p. 114, pi. 190, figs. 1831, 1832, 1795; not Pleurotoma coronata Lamarck, 1803, originally described as Fusus. Type living on the coast of Guinea, West Africa. A specimen similar to that figured by Chemnitz is shown on plate 25, figures 16a, 16&. Shell relatively large, of medium weight, generally with a high or moderately high spire, turricu- lated, with an anterior canal of variable length, typically short ; sculptured below the angle with axial ribs and spiral cords, sometimes of approximately equal development and fornimg a network with small nodular points at the intersections, sometimes with coarse axial ribs forming elongate nodes on the shoulders of the whorls and crossed by rugose spirals weaker at the intersections; above the angle the area of the sUt-band or anal fasciole imsculptured except for growth lines concave toward the aperture, and in typical species above the slit-band and immediately below the suture one or more additional nodular spirals, the upper nodes sometimes standing out like a collar or crown of thorns or spines; sutures high on the preceding whorl, channeled, coarsely or finely flexuous according to the sculpture of the preceding whorl; aperture ovate, outer lip simple except for the slight crenu- lations of the edge caused by the sculpture and the moderately deep, rounded posterior smus situated above the shoulder but separated from the suture by the additional sculptured area just described, the additional sculptured area projecting outward and forming a narrow posterior canal; imier Up covered with a thin callus, without any pile of shelly material below the suture ; columella straight or sUghtly flexed, often slightly umbilicate, typically short but more often somewhat produced and with a distinctly defuied anterior canal which may be very slightly enlarged and twisted at the extremity; operculum homy, with the nucleus near the middle of the columellar side. Geologic range: Cretaceous to Recent. Distribution: Tropical and subtropical waters of all oceans. The genus Clavatula is considered here ahead of Turris, the type genus of the family, because it is one of the genera that appeared early in the fossil record and is probably the closest representative of the archetype from which the family was derived. The name Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 483 Clavahda is one of the oldest in the family, being second only to Turris with its synonym Pleurotoma; and as it applies to a group of forms which are considered generically dis- tinct from Ttirris, it must be clearly defined before the status of many of the later names can be determined. The name Clavatula has been misused, neglected, or applied very indefinitely to a group of forms which most writers have considered foreign to their territory. Clavatula imperialis Lamarck has long been cited erroneously as the type; and although that species is probably congeneric with Clavatula coronata, it is of such a peculiar form that related species have not been easily recognized. Many of the species formerly called Surcula and Turricula should be included. Clavatula coronata appears to be very variable in char- acter, including within its range of variation forms which some writers would be inclined to separate into different genera. Chemnitz described one of the varieties in an earlier volume of the "Conchylien Cabinet" (Vol. 4, p. 176, figured on Vignette 39, fig. C, p. 143, 1780) as Turris babylonica coronata, and this variety has since been recognized as Clava- tula muricata Lamarck. It is distinguished from the typical variety of coronata which Lamarck cited in describing Clavatula by its stumpy spire, relatively longer columella, and its more prominent spines.' The variety bimarginata Lamarck, which is considered conspecific with coronata by Deshayes and Tryon, is distinguished by its larger size, its longer columella, and its less developed spines. = The various figures of these varieties and the figures given by Tryon of additional varieties from approximately the same localities serve to bridge completely the supposed gaps between the extreme forms. The genus Clavatula as illustrated by its type species is a generalized form. The notch and sculpture are irregular and variable, intermediate in character between the cor- responding features shown by the various main divisions of the family. Hence it is that Clavatula is suspected of being the ancestor of the family. Perrona has been derived from a form of Clavatula with the suture high on the preceding whorl by a reduction of the notch and the loss of nearly all the sculpture; Melatoma, Moniliopsis, Pseudomelatoma, Borsonia, and Spirotropis have been derived from a similar form by a heightening of the spire, a shortening of the columella, a reduction of the notch, and the loss of sculpture; Turris, Hemipleurotoma, Cochlespira, Genota, Turricula, Aforia, Ancistrosyrinx, Surculites, Pleurotomoides, Lora, etc., have been derived in a similar way through a modification of the notch and of the general shape and by a simplification of the sculpture in successive stages as described below; Clavus, Cythara, Mangelia, Clathurella, Raphitoma, etc., have been derived by an armoring of the outer lip and notch and at the same time a reduction in size, a modification of the sculpture and a shortening of the canal, also in successive stages; and Scobinella has been derived by the development of strong folds on the colu- mella. Thus practically all the members of the family can be traced directly or indirectly from a Clavatula-\ike ancestor, and the family unity is explained. It is to be expected, of course, that further study along these lines will show that the relations are much more complex than they are here described, but the writers believe that a beginning is made toward an understanding of the group, and that most of the genetic series are outlined approximately correctly. Since the various forms of Clavatula grade without any essential break into forms representative of the main branches of the family, it is necessary to split off the first members of the several series arbitrarily, and there is of course room for differ- ' C. coronata var. muricata (Lamarck) is figured by Kiener, Spfic. Gin. Icon. Coq. Viv.l Vol. 5, Pleurotome, p. 24, pi. 17, figs. 2, 2a, 1839-40; by Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 5, species 31, 1843; and by Tryon, Man. Conch., Vol. 6, p. 229, pi. 8, fig. 22, 1884. ' C. coronata var. bimarginata (Lamarck) — see Deshayes in Lamarck, Hist. Nat. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 9, p. 360. 1843, note on Pleurotoma taxus Kiener. This variety figured by Kiener, Sp^c. G^n. Icon. Coq. Viv., Vol. 5, Pleurotome, p. 29, pi. 2, figs. 2, 1839-40; by Reeve, Conch. Icon., Vol. 1, Pleurotoma, p\. 5, species 34, 1843; and by Tryon, Man. Conch., Vol. 6, p. 229. pi. 8, fig. 15, 1884. 484 San Diego Society of Natural History [Memoirs ences of opinion about where the limits should be set. Cretaceous species of Turridce, at least some of which appear to be congeneric with the type of Clavahda, though perhaps more closely related to the subgenus Knefastia, are described and illustrated by Wade.' Subgenus CLAVATULA, s. s. Suture mounting high on the preceding whorl, prominently sculptured with nodules or spines, the anal fasciole lying in a deeply concave area below this upper sculptured band. Geologic range: Miocene and Pliocene of Europe (fide Cossmann). Distribution: West Coast of Africa. The subgenus which has, through the chances of nomenclatorial history, become typ- ical is leaning strongly toward Perrona. It includes the type species and its varieties, also Clavatula iynperialis Lamarck, though the latter is a somewhat odd form, and others reviewed and illustrated by Tryon. The type and its variety bimarginata are illustrated herewith for comparison (plate 25, figures 16a, 16b, and 14a, 146, respectively). Subgenus KNEFASTIA Ball, 1919 Knefastia Dall, Proc. V. S. Nat. Mus., Vol. 56, p. 3, 1919; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 167, 1928. Type (by original designation), "Pleurotoma olivacea Sowerby, 1833, not of Reeve, 1843, + funiculata Valenciennes, 1839." Shell large, with coarse axial and spiral sculpture, biconical, canal of moderate length, notch moderate, roimded, somewhat distant from the suture, not armored; suture not so high on the pre- cedmg whorl as in typical Clavatula, and the sculpture above the slit-band not so prominent. Geologic range: Cretaceous to Recent; Miocene of the West Indies (fide Woodring). Distribution: Gulf of California to Ecuador. These forms are very much like C. coronata var. bimarginata (Lamarck) in character, except that the suture is not so high on the preceding whorl and the sculpture between the anal fasciole and the suture is confined to an inconspicuous narrow band. These species are evidently leaning toward Turricula, but the strength of the axial sculpture, the general shape, and the position of the notch relate them more closely with Clavatula. Clavatula olivacea and C. tuberculifera (Broderip and Sowerby) are very similar in generic characters to C. ripleyana (Conrad) from the eastern Cretaceous. Clavatula (Knefastia) resina (Dall),'- a species living in the Gulf of Panama, apparently belongs to this group; but T. nigricans Dall, referred by its author to Knefastia, is probably a Turricula. Clavatula (Knefastia) olivacea (Sowerby) Plate 25, Figures 15a, 156 Pleurotoma olivacea Sowerby, Proc. Zool. Soc. London, p. 136, 1833; Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 4, species 27, 1843; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, pp. 208, 271, 330, 1857. Pleurotoma funiculata Valenciennes in Iviener, Sp6c. G6n. et Icon. Coq. Viv., Vol. 5, Pleurolome, p. 24, pi. 16, figs. 1, 1839; Reeve, Conch. Icon., Vol. 1; Pleurotoma, pi. 11, fig. 95, 1843; Carpenter, Cat. Reigen CoU. Mazatlan MoU. Brit. Mus., p. 390, 1857; Brit. Assn. Adv. Sci., Rept. for 1856, pp. 226, 238, 258, 282, 294, 1857; Rept. for 1863, pp. 538, 541, 623, 1864. Hurcula olivacea Sowerby, Tryon, Man. Conch., Vol. 6, p. 237, pL 5, figs. 69, 70, pi. 34, fig. 3, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 207, 1909. ' Wade, Bruce, "The Fauna of the Ripley Formation on Coon Creek, Tennessee," Prof Paper 137 U. S. Geol. Survey, pp. 110-113, pis. 23-27, in part, 1926. 2 Turria (Surcula) resina Dall, Bull. Mus. Comp. Zool., Vol. 43, p. 264. 1908. / ClalhTodrillia resina Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 16, pi. 2, fig. 4, 1919. VoLTjME I ] Pliocene and Pleistocene Mollusca or California 485 Shell large, biconic, spire moderately high, whorls shouldered, with aliout ten coarse, rounded, axial ribs which project from the shoulder like nodes, crossed by coarse spiral riblets and stride, area of the anal fasciole above the shoulder smooth except for lines of growth, concave, separated from the suture by an inconspicuous band, the strength of the shoulder varyuig with the slope and width of the anal fasciole; aperture oval, elongate, mcluduag the canal about half the length of the shell, outer lip made irregular by the sculpture, posterior notch deep, rounded, midway between the angle and the suture, columella of medium length, straight, sometimes umbilicate, inner lip inconspicuous, anterior canal indistinctly defined, about three-fifths as long and as wide as the aperture, slightly flaring at the end; operculum "formed hke an obtuse-angled triangle, with the base along the colu- mella, nucleus near the canal, the other angles rounded." Dimensions (of figured specimen): Altitude, 50 mm.; length of aperture (mcluding canal), 26 mm.; maximum diameter, 21 mm. Type specimen: In the British Museum ? Type locality: West Colombia. Pleistocene: Coast of Oaxaca, Mexico, collected by R. H. Palmer. Liirlng: West coast of Mexico to Ecuador. Reeve's figure of olivacea is more round shouldered ih.a.\\ Juniculata (Valenciennes in Kiener), which equals, according to Dall, olivacea (Sowerby); but it does not seem as if the two should be separated. Some specimens are more round shouldered than others. This species may be but a variety of the next. Clavatula (Knefastia) tuberculifera (Broderip and Sowerby) Plate 25, Figures lOo, 106 Pkuroloma tuberculifera Broderip and Sowerby, Zool. Journ., Vol. 4, p. 378, 1829; Reeve, Conch. Icon., Vol. 1, Pleuro- toma, pi. 8, species 63, 1843. Surcula tuberculifera Broderip and Sowerby, Tryon, Man. Conch., Vol. 6, p. 238, pi. 5, fig. 68, pi. 10, fig. 60, 1884. Shell hke that of olivacea, but with narrower tabulation, more rounded shoulder, and higher spire. Dimensions (of figured specimen): Altitude, 61 mm.; length of aperture (including canal), 27 mm.; maximum diameter, 20 mm. Living: In the Gulf of California. Section Carinodrillia Dall, 1919 Cannodnllia Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 17, 1919. Type (by original designation), ClathrodrilUa (Carinodrillia) halis Dall, described loc. cit. and figured pi. 5, fig. 4, living La Paz, Lower California. Like the section Knefastia, s. s., but smaller, with a higher spire and shorter aperture, the sculp- tural band between the anal fasciole and the suture inconspicuous. All the species assigned by Dall to the section Carinodrillia, except the one he desig- nated as type, belong to a strongly carinated group in the subgenus ClathrodrilUa of Clavus. The species halis, however, has a Clavatula notch and is apparently related to olivacea, resembling very closely young specimens of the latter. Subgenus TRACHYLOCHETUS Cossmann, 1889 Trachylochetus Cossmann, Ann. Soc. Roy. Malac. Belgique, Vol. 24 (Ser. 4, Vol. 4), p. 250, 1889; Ess. Paleo. Comp., Vol. 2, p. 67, 1896. Type (by original designation), Pleurotoma desniia Edwards, Eoc. Moll., p. 240, pi. 27, fig. 5, 1856, also figured by Cossmann, Ess., Vol. 2, p. 67, pi. 4, figs. 17-18, 1896, Eocene of the Anglo-Franco-Belgian Basin. 486 San Diego Society of Natural History [ Memoirs Shell like that of the typical subgenus but with less conspicuous subsutural band; smaller and with finer sculpture than that of the subgenus Knefastia. Geologic range : Eocene to Miocene of Europe (Cossmann) . Living distribution: La Paz, Lower California. Cossmann recognized Trachylochetus as a subgenus of Clavatula in 1896. The peculiar record of its range and distribution is probably due to the fact that most workers are not familiar enough with the form to recognize it. Clavatula (Trachylochetus) andromeda (Dall)^ is very similar to C desmia. Genus TURRICULA Schumacher, 1817 Not Turricula Klein, pre-LiniiEean. Not Tvrriada Hermann, Tab. aff. Anim., Ed. 2, tabula G, 1783, cited in Sherborn's Index Anim., p. 1007, 1902, but not nomenclatorially available, see Iredale, Proc. Malac. Soc. London, Vol. 11, p. 294, 1915. Turricida Schumacher, Ess. d'un Nouv. Syst., p. 217, 1817; Iredale, Proc. Malac. Soc. London, Vol. 12, p. 324, 1917; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 315, 1918; Hedley, Records Australian Mus., Vol. 13, p. 253, 1922; Thiele, Wiss. Erg. Deutsch. Tiefsee-Exped., Vol. 17, pp. 205, 207, 1925. Svmila H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 88, 1853, new name for Turricula Schumacher, not IClein, and 31 species cited, including jai'o?ii/s Linnieus; Cossmann, Ess. Palto. Comp., Vol. 2, p. 69, 1896, type cited Murex javanus Linnaeus. Surgula Weinkauff, Martini-Chemnitz Syst. Conch. Cab., Ed. 2, Vol. 4, pt. 3, 1875 {fide Dall), probably merely a transliteration. Type (by monotypy), Turricula flammea Schumacher based on "Murex javanus Linna>us" Chemnitz, Neues Syst. Conchyl. Cab., Vol. 4, p. 172, pi. 143, figs. 13.36-1338, 1870 + Turris javanus Bolten + Murex tornatus Dillwyn, 1817, not Turris tornatum Bolten, 1798, a true Turris, + Pleurotoma "javana Linnaeus," Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 4, sp. 26, 1843, + Siircula tornata Dillwyn, Tryon, Man. Conch., Vol. 6, p. 237, pi. 5, fig. 62, 1884, etc.; figured herewith, plate 25, figs. 9a, 96. Shell large, of moderate thickness, with a high spire and typically a long anterior canal which is clearly differentiated from the aperture ; whorls usually shouldered above the middle, concave above the shoulder, convex below, sculptured by spiral Imes (which are obsolete on the type except on the lower part of the body whorl), and sometimes by nodes on the shoulder or short ribs extending obliquely downward; aperture wde, ovate, about half again as long as the anterior canal, the canal and ajierture together being usually about half as long as the whole shell; outer hp thin, rounding in abruptly to form the edge of the anterior canal and curving backwards posteriorly mto the deep rounded notch which lies in the nearlj' smooth concave area between the shoulder and the suture, above the notch the lip curvmg outward agam at the end of a narrow sutural band which recalls the sutural band of Clavatula, uiner lip slightly resorbed, columella flexuous, elongated, anterior canal parallel-sided, not wide, slightly notched behind; operculum with a nucleus on one side like that of Clavatula. Geologic range: Cretaceous to Recent (fide Cossmann). Distribution: Tropical seas, especially of the Pacific. The nomenclature of this genus seems to be on the point of settling down. The name Surcula was proposed unnecessarily according to the modern rules of nomenclature for Turricula Schumacher believed to be preoccupied by the pre-Linnsean Klein. According to the writers' interpretation of the rules, Schumacher's species, T. flammea, and the 31 species listed by the Adams brothers are all available for the type of Surcula, inasmuch as Surcula was not proposed definitely as a new name for Turricula Schumacher alone but for Turricula Schumacher and the 31 species. The type of Surcula has been cited several times as Murex javanus Linnseus, not "Murex javanus Linnseus" Chemnitz, Reeve, etc., > ClallimlriUia andramcria Divll. Proc. U. S. Nat. Mus., Vol. .50. p. 16. pi. 2, fig. 2. 1919. Volume I ) PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 487 and as this species is in the original list it should be considered the type. Surcula is not, however, sufficiently distinct from Turricula to be of use, for it differs only in being more strongly, more normally sculptured. The true Turricula javana (Linnseus) is figured by Tryon (Man. Conch., Vol. 6, p. 237, pi. 5, figs. 63-65, 1884), and by Reeve as Pleuroloma nodifera Lamarck (Conch. Icon., Vol. 1, Pleuroloma, pi. 4, sp. 28, 1843). Turricula is related to Clavatula, not only by its operculum but also by its general shell characters. Thiele says that there are so many intermediate species that he doubts if the two genera can be distinguished. However, it seems advisable to make the separa- tion, even if it is somewhat arbitrary, at the point where the anterior canal becomes long and narrow, the sutural band inconspicuous, and the sculpture simpler. Other points of difference can probably be worked out more or less satisfactorily, and although the inter- gradations are evident, the groups seem to be on the whole fairly natural units. It is even more difficult to separate Turricula from Turris, especially in the older formations, and Harris decided that it was not worth while to try. In most cases, however, the separation can be made on the basis of the shape and position of the notch, as well as by the oper- culum in living species. In Turricula the notch is above the angle and rounded; in Turris it is on the angle and is deep and square-ended or at least angular. Turricula grades into the early forms of Spirotropis through such species as Turricula piercei (Arnold), and the final basis of separation is the short canal of the latter. It also grades into and is the probable ancestor of Aforia and related groups which have a still longer anterior canal in relation to the rest of the shell. Surculites and Genota are probably related, but they do not have the anterior canal defined; in them the body whorl rounds down in a smooth , sometimes nearly straight curve to the base. Priscofustis and Pleurofusia are also related . The type of Turricula is an almost smooth form, with faint striations only on the lower half of the body whorl, most of the sculpture having become obsolete. The true Turricula javana (Linnseus) has the same shape but retains a fairly strong spiral sculpture from the shoulder downward and also on the sutural band, with in addition a row of some- what irregular small oblique nodes on the shoulder. These two species, which were con- fused by Chemnitz and others, should be separated only specifically. The same is true, of the species selected as genotypes of some of the new genera proposed by Casey^ such as Proiosurcula and Orthosurcula. Casey's work has been unfavorably but justly criticised by Cossmann,- who has concluded that these two names at least should not be separated from Surcula (= Turricula). Turricula australis (Lamarck), which Casey includes in Orthosurcula," has a longer, straighter anterior canal and stronger, beaded spiral cords than Turricula flammea; but the differences are specific, no more. Turricula kaderleyi (Lischke) has faint spiral sculpture and strong, elongated, obUque nodes on the angle being similar in general form and sculpture to T. ochsneri (Anderson and Martin) . The extreme variant from the type in the opposite direction from T. australis is T. maculosa (Sowerby), having a relatively short, poorly differentiated anterior canal, and sharp rounded nodes on the angle. This and related species might better deserve a sectional name than many of the artificially separated groups already named ; but the intermediate species T. catena (Reeve) shows clearly the relationship, and it appears that nothing would be gained by introducing a new name. The writers believe that no new generic names should be proposed in the Turridce until a beginning has been made toward an understand- ing of the relationships of the three hundred odd supposed generic groups already named, a thing which obviously no one yet has done. ' Casey, Trans. Acad. Sci., St. Louis, Vol. 14, pp. 123-170. 1904. = Cossmann, Ess. Pal«o. Comp., Vol. 7, pp. 218-224, 1906. 't 488 San Diego Society of Natural History [ Memoirs Turricula piercei (Arnold) Pleurotoma {Bathyloma) piercei Arnold, Bull. 396, U. S. Geol. Survey, p. 61, pi. 9, fig. 7, Jan. 1.5, 1910; figure reprinted in Bull. 398, pi. 31, fig. 7, 1910. Bathyloma -piercei Arnold, Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 179, 1912; Anderson and Martin, Vol. 4, p. 42, 1914. Shell of small or moderate size for this genus, nearly smooth except for remnants of nodulations on the early whorls; notch, angulation of the whorls, etc., normal for the genus ; columella only moder- ately long, somewhat flexuous, aperture and canal about half the length of the shell. Middle Miocene: Monterey-Temblor stage, of the San Joaquin basin, California. This species is similar to and probably intergrades with Turricula ochsneri (Anderson and Martin), but is distinguished by its obsolete sculpture. It is on the borderline be- tween the genera Turricula and Spirotropis, and is here classed with the former because of its obvious relationship with T. ochsneri and because of its columella, which is longer than is usual for Spirotropis. Turricula ochsneri (Anderson and Martin) Drillia ochsneri Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 90, pi. 6, figs. 9a, 96, 9c, 1914. Drillia wilsoni Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 91, pi. 6, figs. lOo, 10b, lOf, 1914. ? Surcula insulx Dall and Ochsner, Proc. Calif. Acad. Sci., Ser. 4, Vol. 17, p. 104, pi. 6, fig. 12, 1928. Shell of moderate size, spire elevated, whorls angulated above the middle and surmounted by ten to eleven oblique axial ribs starting on the angle and dymg out downward, crossed by faint spiral striations (usually eroded off), about four exposed on the spire whorls and twenty to twenty-two on the body whorl; aperture and canal together about half as long as the entire shell, but varying in length, posterior notch above the angle, deep, rounded, leavmg behind it the concave fasciolar area and accounting for the angulation, columella slightly flexuous. Dimensions (of type of wilsoni from Anderson and Martin) : Altitude with defective apex, 47 mm.; diameter of the last whorl, 18 mm.; length of the aperture including the canal, 2.3 mm. Type specimens: All at the California Academy of Sciences. Type localities: Of ochsneri, middle Miocene of Barkers Ranch, Kern County, Cali- fornia; of wilsoni, middle Miocene of eastern San Luis Obispo County, California; of insulce, probable Pliocene on east shore of Indefatigable Island, Galapagos Group. Miocene: Type localities of ochsneri and irilsoni, middle Miocene; Santa Margarita formation, upper Miocene, from well cores of the Fruitvale district northwest of Bakersfield, California, si.x specimens(H. R. G.). ? Pliocene: Type locality of insulx. Anderson and Martin separated ochsneri from wilsoni probably because the latter is relatively more elongate, though they did not say so. There appears to be no other dif- ference, and this character is too variable to be of significance. The Pliocene form, insulce, is slightly more elongate and smaller, and may be varietally or even specifically distinct. It is not unlikely that the species as a whole is merely a variety of T. piercei (Arnold) in which the ribs did not become obsolete so soon. This species bears some simi- larity to T. 7naura (Sowerby), which is living at Guayaquil, Ecuador. It is more like a typical Turricula than is T. maculosa (Sowerby). Turricula maculosa (Sowerby) Plate 25, Figures 11a, lib Pleurotoma macidosa Sowerby, Proc. Zool. Soc. London, p. 135, 1833; Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 6, species 45, 1843. ■Si/rcwia maculosa Sowerby, Tryon, Man. Conch., Vol. 6, p. 236, pi. 5, fig. 57, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 207, 1909; Nautilus, Vol. 32, p. 23, 1918. Turricula hurragei Bartsch, Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 149, 151, 1924. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 489 Shell rather small for the genus, high spired, whorls strongly angulated, the angulation coming at about the middle of the spire whorls, whorls concave above, only very slightly convex below, slop- ing inward, smooth except for very faint spiral grooves and on the angle small sharp nodes about ten to a whorl; aperture and canal together only about two-fifths as long as the shell, narrow, almost parallel-sided, outer lip thin, almost straight, the posterior notch above the angle, deep, rounded, inner lip slightly resorbed, columella stout, almost straight, anterior canal poorly defined, about two- thirds as long as the aperture. Dimensions: Altitude, 34 mm. ; length of aperture and canal, 13.5 mm. ; diameter of body whorl, 10 mm. Type specimen: In the Museum Cuming. Type locality: West Colombia, in sandy mud at a depth of sixteen fathoms. Pleistocene: Lower Quaternary of Magdalena Bay, Lower California (Jordan, 1924); Pleistocene of Mag- dalena Bay, Lower California (Dall, 1918); upper Quaternary of San Ignacio Lagoon, Lower Cali- fornia (Jordan, 1924). Living: Gulf of California to Guayaquil, Ecuador (Dall, 1909). This species resembles in general form Clavus unimaculatus (Sowerby), but is easily distinguishable by its unarmored posterior notch, its longer columella, and its unnotched anterior canal. As mentioned above, it is an extreme form of Turricula. Its passage to Spirotropis is evident, though it clearly belongs to this genus. The name burragei Bartch, used by Jordan, appears to be a manuscript name, for a prolonged search of the literature has failed to reveal a description. Jordan's specimens were identified by Dall. They are now in the collection at Stanford University, and clearly belong to maculosa (Sowerby). Turricula libya Dall Turricula libya Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 2, pi. 2, fig. 5, 1919. Living: Off Cape San Lucas, Lower California. This form appears to be a slightly shorter, more solid variety of T. maculosa. Turricula nigricans Dall Turricula (Knejaslia) nigricans Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 3, pi. 2, fig. 6, 1919. hiving: Off Lower California. This species is similar to T. maculosa but has narrower ribs, only about eight to the whorl, extending downward more persistently than the nodes of maculosa. The spiral sculpture is plainer, but this character is too variable to be of significance. It is possible that nigricans is another synonym or variety of maculosa, with which its relationship is evident. It is comparatively remotely related to Knejaslia. Subgenus PLEUROFUSIA de Gregorio, 1890 Pleurofusia de Gregorio, "Mon. Faune Eoc. Alabama," Annales de Geologie et de Pal^ontologie, Vol. 7, p. 33, Palermo, 1890; Casey, Trans. Acad. Soi. St. Louis, Vol. 14, p. 152, 1904; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 166, 1928. Tropisurcula Casey, Trans. Acad. Sci. St. Louis, Vol. 14, p. 1.53, 1904; Cossmann, Ess. Palfo. Comp., Vol. 7, p. 222, 1906, type cited Drillin caseyi Aldrich, Eocene to Oligocene; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 166, 1928. .^ Fusiturricula Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 165, 1928. type (by original designation) Turris (Surcula) fusinella Dall, living in the Gulf of Panama, described and figured in the Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 261, pi. 14, fig. 7, 1908. Type (by original designation), Pleurotoma [Pleurofusia) longirostropsis de Gre- gorio from the Eocene of Alabama, described and figured by de Gregorio, op. cit., p. 34, 490 San Diego Society of Natural History [ Memoirs pi. 2, figs. 26, 27, 1890. This species is said to be similar to Pleurotoma servata Conrad, Journ. Acad. Nat. Sci., Phila., Ser. 2, Vol. 1, p. 115, pi. 11, fig. 18, 1848. Shell elongate, fusiform, with a high spire and a long, straight anterior canal; whorls shouldered, and sculptured with axial nodes or riblets crossed by spiral lines; notch like that of typical Turricula. Geologic range: Eocene of California and Washington, Eocene and Oligocene of south- eastern United States, Miocene of the West Indies. Distribution : West coast of Panama and Mexico. This subgenus is very closely related to the typical subgenus, so closely indeed that Cossmann considered it a synonym. Its unusually high spire, the exaggerated length of the columella below the constriction of the body whorl, and the stronger sculpture serve to distinguish it as a variational extreme. Casey and Woodring separated their genera on the basis of different protoconchs; but as pointed out above, the writers do not believe this character alone to be a reliable basis for separating or classifying genera. Turricula (Pleurofusia) fresnoensis (Arnold) from the upper Eocene of the Coalinga district, middle California, and its probable synonym Turricula (Pleurofusia) cowlitzensis (Weaver) from the same horizon in Washington apparently should be classed in this sub- genus.' This gi'oup is the only one on the Pacific coast that might cast doubt on the present interpretation of the genus Priscofusus. The two groups are easily distinguished by the position and the character of the posterior notch, but this character is not shown in Conrad's figure of the type of Priscofusus. However, Conrad's type is said to have come from the Miocene where Priscofusus is common, and Pleurofusia has not been reported from the Miocene of the northwest. The Pleurotoma servatoidea Aldrich, mentioned by Casey as distinguished from Pleurofusia by its notch, probably belongs to Priscofusus. Genus PRISCOFUSUS Conrad, 1865 Priscofusus Conrad, Amer. Journ. Conch,, Vol. 1, p. 150, 1865, original list includes Fusus corpulentus Conrad, F. geniculus Conrad, and others; Cossmann, Ess. Pal6o. Comp., Vol. 4, p. 8, 1901, type designated F. geniculus Conrad; Dall, Prof. Paper 59 U. S. Geol. Survey, p. 39, 1909, in part, type cited F. corpulentus Conrad. Type (by subsequent designation, Cossmann, 1901), Fusus geniculus Conrad, de- scribed and figured in the U. S. Expl. Exped. (Wilkes), Vol. 10, Geology, p. 728, Geology Atlas, pi. 20, fig. 3, 1849, and described by Dall, Prof. Paper 59 U. S. Geol. Survey, p. 40, 1909. Shell fusiform, with a high spire and a long, somewhat curving, anterior canal, whorls angulated, sculptured by niunerous strong revolvmg lines, and by low axial undulations, nodes, or ribs on the angle, growth lines bending back below the suture in a broad, shallow, rounded embayment with its maximum depth nearly out at the periphery. Geologic range: (Eocene ?), Oligocene and Miocene of the Pacific coast of the United States. This genus name has remained for a long time practically a nomen dubium, and the obscurity in which it was hidden was increased by Dall's erroneous citation of Fusus cor- pulentus as the type. F. corpulentus Conrad was described and figured in the same place as F. geniculus (pi. 20, fig. 4), and is now identified as Agasoma (Bruclarkia) sp., possibly the same as Priscofusus nodiferus Conrad also figured in the same place (pi. 20, figs. 12, ' Pleurotoma fresnoensis Arnold, Bull. 39t) U. S. Geol. Survey, p. 53, pi. 4, fig. 23, Jan. 15, 1910, figure reprinted in Bull. 398, pi. 26, fig. 23, 1910. Surcula cowlitzensis Weaver, Geol. Surv. Wash., Bull. No. 15, p. 53, pi. 3, figs. 30, 36, pi. 11. fig. SB. 1912. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 491 an impression, and 12a) but not named until 1865, and possibly also the same as the much better known Agasoma acuminatum Anderson and Martin (Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 73, pi. 5, figs. 4a, 46, 1914). Hence, if an earlier designation of type should be found making corpulentus the type, Bruclarkia would become a synonym and Agasoma a subgenus. However, Cossmann's designation appears to be valid, and the species he cited is very different. According to the figures given by Dall, the total length is more than four times as great as the maximum diameter. The writers are not now able to identify this species, but it is fairly certain to what group it belongs. This group probably should include most of the following: Priscofusus hecoxi (Arnold) Fusus hecoxi Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 371, pi. 33, fig. 8, 1908. Drillia cJiehalisensis Weaver, Bull. Wash. Geol. Survey, No. 15, p. 78, pi. 6, figs. 65, 66, pi. 14, fig. 125, 1912. Drilia hecoxi (Arnold), Drillia chehalisensis (Arnold), Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 30, pi. 4, fig. 48, 1916. Oligocene: Of California, Oregon, and Washington. Arnold's type has a wider apical angle than Weaver's, but Weaver himself recognized the synonymy. Priscofusus sanctaecrucis (Arnold) Fusus sanctaicTucis Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 371, pi. 33, fig. 3, 1908. Oligocene: Of California. Priscofusus medialis (Conrad) Cerithium mediale Conrad, U. S. Expl. Exped. (Wilkes), Vol. 10, Geology, p. 728, Geology Atlas, pi. 20, figs. 1, la, 1849. Priscofusus medialis Conrad, Amer. Journ. Conch., Vol. 1, p. 150, 1865. Fusus (Priscofusus) medialis Conrad, Dall, Prof. Paper 59 U. S. Geol. Survey, p. 41, 1909. Miocene: Of Oregon. Priscofusus canimani (Dall) Tunis cammani Dall, Prof. Paper 59 U. S. Geol. Survey, p. 25, pi. 4, figs. 12, 13, 14, 1909; ?? Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 238, 240, 258, 1916; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 93, 1922. ? Turris carlsoni Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 89, pi. 5, figs. 2a, 26, 1914. Miocene: Of Oregon. Martin's identifications of specimens from the upper Miocene and PUocene of north- ern California appear very doubtful. Ball's specimens were very poor casts. They prob- ably belong either with carlsoni or with medialis. Priscofusus coosensis (Dall) Turris coosensis Dall, Prof. Paper 59 U. S. Geol. Survey, p. 24, pi. 2, fig. 3, 1909. Turris coli Dall, Prof. Paper 59 U. S. Geol. Survey, p. 26, pi. 4, fig. 2, 1909. Upper Miocene: Of Oregon. Priscofusus lincolnensis (Anderson and Martin) Turris lincolnensis Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 88, pi. 6, fig. 8, 1914. Not Turris lincolnensis Van Winkle, 1918, renamed "Borsonella ?" nuncapalia Hanna, 1924. Miocene: Of Oregon. From a study of this group of species it is evident that there is here a natural group, to which, so far as the writers could ascertain, no other appropriate name has been applied. It is fortunate then that Cossmann selected one of them for the type of Priscofusus. The 492 San Diego Society of Natural History [Memoirs type resembles no other species so much as P. hecoxi (Arnold), as figured by Weaver; and Conrad's description shows that it is even more like that species than the figure indicates, for Conrad says the angle is below the middle of the whorls, whereas he figured it above. Nevertheless, the riblets on P. geniculus are more elongate, and the two species are said to come from different horizons, so the best that can be done is to say that the two are related. It is a pity that Dall did not figure Conrad's types when he had them before him. It is now left to the paleontologists of the Northwest to identify these old species. Priscofusus is characterized by its fusiform shape and by its broad, almost Fusus-\ike posterior sinuation, which takes the place of the posterior notch. It is certainly not a characteristic form of notch for the Turridcv, and it is somewhat doubtful whether the genus should be placed here or with the Fasciolariidce as Dall had it. However, the tendency lately has been to class the species with the Turridw, and this alternative is more probably correct. The group appears to be related on the one hand to the shallow-sinus species of Surculites and on the other to the fusiform species of Turricula. Its notch is like that of the older Turridce, like that of Turricula jasciolata Wade' from the Tennessee Cretaceous. Martin's identification of specimens as belonging to the same species as Dall's casts of P. cammani is the only record of this genus in the Pliocene, and this record is here strongly questioned. Genus SURCULITES Conrad, 1865 Surculites Conrad, Amer. Journ. Conch., Vol. 1, p. 213, 1865; Whitfield, Mon. No. 18, U. S. Geol. Survey, p. 217, 1892; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 420, 1926. Type (by monotypy), Surcula (Surculites) annosa Conrad, loc. cit., and pi. 20, fig. 9, 1865, a better figure of the type specimen given by Whitfield, loc. cit., and pi. 33, fig. 14, 1892. Shell of medium to large size, of general biconic form, usually somewhat turreted; whorls angu- lated, above the angle a broad, nearly flat, often concave area, unsculptured except for growth lines, this area either sloping at a low angle directly toward the preceding whorl and then turning up ab- ruptly and forming a sutural collar, or starting at a low angle and curving concavely upward toward the suture high on the preceding whorl, or starting fairly steeply and reaching the suture with scarcely any curvature, sometimes producmg in the last case an almost smoothly conical spire, shoulder either smooth or surmoimted by a row of nodes, sometimes sharp, occasionally the nodes extendmg down- wards as short riblets, the whorl on and below the shoulder sculptured with spiral lines, usually fine, and if well developed showing primary, secondary, and tertiary series, growth Imes sometimes as strong as the spiral sculpture ; aperture varymg from two-fifths to a half the length of the shell, the outer lip running upward from the base in a nearly straight line (apertural view) to the shoulder and then turning toward the suture with an acute, right, or obtuse angle accordmg to the slope of the area already described, from the side view curving outward in a broad arc ; posterior notch broad and shal- low, rounded, extendmg across the area above the shoulder; uiner lip slightly resorbed, columella nearly straight, sometimes slightly flexed, anterior canal short, usually broad and not well defined, with a shallow notch behind. At first sight it might be said that this genus as here outlined includes a number of forms differing too widely to be held within the limits of a single genus. The typical sub- genus, the extreme with very tabulate whorls, appears to be a branch that split off and died out in the early Tertiary. The subgenus Cryptoconus, the non-tabulate, compara- tively deep-notched extreme, apparently did the same. The intermediate, more normal subgenus Clinura lived on through the Miocene, possibly into the lower Pliocene of Italy, and gave rise to Megasurcula in California, which is still living. The subgenus Pseudotoma in Europe is analogous to the American Megasurcula, and may have been derived from 1 Turricula Jasciolata Wade, Prof. Paper 137 U. S. Geol. Survey, p. 112, pi. 36, figs. 3, 4, 1926. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 493 Surculites direct (for it is very similar in form), or through the subgenus Clinura. Pseudo- toma is said by Cossmann to be still living. The genus as a whole is probably a derivative from Turricida, splitting off in early Eocene or late Cretaceous time; and its various sub- genera show such striking similarities to Turricula (olim Surcula) that most of them have been included at one time or another in that genus. They can be distinguished, however, by the broader posterior notch and the short anterior canal and by the fact that the outer lip is not curved in rapidly below the aperture to define the canal as in Turricula. Although the extreme forms of the various subgenera appear very distinct, a study of the variations of the species in the different groups and of the intermediate species shows that the treatment most in accord with nature is to group them all together. For instance, S. (Megasurcula) carpenterianus variety cooperi really looks more like the type of Pseudo- toma than it does Uke the typical variety of the same species, and it bears such a striking resemblance to S. wynootcheensis of the typical subgenus that it seems hardly correct to separate the two subgenerically. The passage between the Eocene Clinuras of California, represented by S. {Clinura) to (Gabb), to Megasurcula through S. keepi Arnold is so grad- ual that it is practically impossible to decide where to draw the line. The living S. (Megasurcula) remondii is so much like S. (Cryptoconus) filosus, the type of Cryptoconus, that it can be told only by the not very different depth of the notch; and S. sinuatus (Gabb) of the typical subgenus bridges the gap between the type and the tabulate var- ieties of S. remondii from the lower Pliocene. Cryptoconus and Pseudotoma confound themselves in intergrading parallel series of variations in the early Tertiary of Europe. It is possible that Mesochilotoma Seeley^ is a still older name for this genus; but as pointed out by Stoliczka, the description is too brief to identify. The chances are greater that it belongs to some other gi'oup. Subgenus SURCULITES, s. s. Shell with sharply angled, tabulate whorls, sloping upward from the shoulder at a low angle toward the preccdmg whorl and leaving a considerable part of the preceding whorl exposed below the shoulder, sutural collar developed to a variable extent, and in well-preserved specimens small nodes on the angle. Geologic dislributio7i: Eocene of New Jersey (Conrad; Whitfield), of California and Washington (Gabb), of England (Stewart); also Miocene of Washington. The typical form of Surculites is represented on the Pacific coast by S. wynootcheensis (Weaver), = S. sinuatus (Gabb), and S. matthewsonii (Gabb).^ S. wynootcheensis (Weaver) has whorls which are fully as tabulate as those of the type species, but they are more rounded below and the sutural collar is somewhat wider. S. sinuatus is practically iden- tical in form with S. amwsus except that the area above the shoulder rises upward in a smooth concave curve instead of being pinched in below a sutural collar. These two spe- cies between them represent the typical form completely. The latter has small nodes on the early whorls, the former retains its nodes almost throughout life. ' Mesochilotoma Seeley. Ann. and Mag. Nat. Hist.. Ser. 3, Vol. 7, p. 284, 1861. type (by monotypy), M. striaUi Seeley, briefly described, loc. cit., but never figured. Cretaceous upper Greensand of Cambridge, England; Stoliczka, Mem. Geol. Survey India, PaliEO. Indica, Vol. 5, p. 68, 1867 (spelled Mesochilostoma) ; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 328. 1918. " Turris wynootcheensis Weaver, Wash. Geol. Survey, Bull. 15, p. 70, pi. 11, figs, 87, 88, 89, 94, pi. 14, fig. 121, 1912; Univ. Wash. Publ. Geol., Vol. 1, p. 52, pi. 5, fig. 63, 1916. ■ • For illustration, discussion, and references on Gabb's two species see Stewart, Proc. Acad. Nat. Sci., Phila., Vol. 78, pp. 420-421, 1926. The best figures of sinuatus are given by Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 5, pi. 10, figs. 2a. 26, 2c, 1915. 494 San Diego Society of Natural History [Memoirs Subgenus CLINURA Bellardi, 1875 Clinura Bellardi, Boll. Societa Malac. Ital., p. 20, 1875, original list includes two species, Pleurotoma calliope Brocchi and Pleurotoma elegantissima Forbes; Mem. R. Accad. di Scienze di Torino, Ser. 2, Vol. 29, p. 204, (1877) 1878, tjTDe cited PI. calliope Brocchi; Cossmann, Ess. Paleo. Comp., Vol. 2, p. 74, 1896. Nekewis Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 421, 1926, type (by original designation) Fasdolaria imshing- toniana Weaver, described and figured by Weaver in Bull. No. 15, Geol. Surv. Wash., p. 52, pi. 1, fig. 5, 1912; also figured by Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 5, p. 72, pi. 10, figs. 7a, 76, 1915. Type (by subsequent designation, Bellardi, 1878), Murex (Pleurotoma) calliope Brocchi, Miocene of Italy, figured by Bellardi, op. cit., p. 205, pi. 7, fig. 1, 1878, and by Cossmann, Ess. Paleo. Comp., Vol. 2, pi. 5, fig. 19, 1896. Shell short and broad; whorls turreted, the area above the angle broad and only slightly concave, sloping up steeply and meetmg the precedmg whorl almost at the angle, angle ornamented with crenu- lations or riblets, sometimes extendmg downwards ; aperture and canal about half the length of the shell, outer lip rumiing up from the base to the periphery nearly in a straight line and then turning at right angles toward the suture, posterior notch very wide and shallow, rounded, columella moderately flexuous, anterior canal short, not wide. Geologic range: Eocene of California, Oregon, and Alabama; Miocene and lower Pliocene of Italy. There are a number of almost perfectly preserved specimens of Surculites (Clinura) washingtonianus (Weaver) in the collection at Stanford University that show even better than the figures how close this species is to the Italian type of the subgenus. Pseudotoma bonellii (Bellardi) from Italy, op. cit., p. 218, pi. 7, fig. 13, 1878, also figured by Cossmann, op. cit., pi. 7, figs. 11, 12, 1896, is probably also a Clinura, and likewise Surculites (Clinura) io (Gabb) from California, see Stewart, loc. cit., and pi. 30, fig. 11, 1926. The writers believe that even though the members of a group of similar forms should occur in widely separated localities, the group should not be dismembered into local genera or subgenera unless they can be separated on the basis of significant objective characters. There seems to be no way of distinguishing Clinura and Nekewis; and Stewart, although he mentions the former, does not attempt to do so. Clinura is closely related to Turricula, and might be considered a variational extreme in the opposite direction from Pleurofusia. It can, however, be distinguished generically by its shorter form and broad, shallow notch. It is even more closely related to Sur- culites proper, Pseudotoma, and Megasurcula, sharing with them the broad conical shape and wide shallow notch, so that it is here not separated from them generically. However, it may be distinguished by its narrower, better formed anterior canal and longer colu- mella. It probably was derived from Turricula, perhaps indirectly, and later gave rise to, or is a branch of the stock that gave rise to, Pseudotoma and Megasurcula. The intergrada- tions between it and the last named are evident in the California and Washington Ter- tiary. Clinura and typical Surculites are both well represented in the Eocene of the Pacific coast, and can be distinguished most easily by the slope of the area above the angle. Clinura lived on into the Miocene, where it is represented by keepi (Arnold), but by this time it had changed over sufficiently so that it is better to include keepi and the related species condonanus (Anderson and Martin) in the subgenus Megasurcula along with the later California species. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 495 Subgenus MEGASURCULA Casey, 1904 Megasurcula Casey, Trans. Acad. Sci., St. Louis, Vol. 14, p. 147, 1904, list consists of PUuroloma {Surcula) carpeiiler- iana Gabb and its variety tryoniana Gabb. Type (here designated), Pleurotoma (Surcula) carpenteriana Gabb. Like Clinura but with a more massive columella and a wider, less clearly differentiated anterior canal, less often turreted, sometimes almost round-whorled like Cryptocon us. Geologic range: Miocene to Recent in California. Distribution: Monterey, California, to Todos Santos Bay, Lower California. This group is barely distinguishable from Pseudotoma, but it is so clearly a descendant of the Pacific coast Eocene Clinuras that it appears to be nearer the truth to keep it separate from Pseudotoma and place it next to Clinura. Surculites (Megasurcula) remondii (Gabb) Plate 25, Figures 5, 6, 7, 8a, Sb "f Mehda" reinondii Gabb, Geo!. Survey Calif., Palseo., Vol. 2, p. 3, pi. 1, fig. 5, 1866. Melula remondii Gabb, Geol. Survey Calif., Pateo., Vol. 2, p. 72, 1868-9; ? Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 176, 1912; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 531, 1922. Pleurotoma {Genota) slearnsiana Raymond, Nautilus, Vol. 18, p. 1, 1904; Vol. 20, p. 38, pi. 2, figs. 4, 5, 6, 1906. Bathytoma carpenteriana Gabb, var. fernaiidoana Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 14, pi. 56, fig. 7, 1907; Arnold and Anderson, Bull. 322 U. S. Geol. Survey, p. 58, pi. 23, fig. 7, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, pp. 210, 213, 1914; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, pp. 544, 550, 1922. "Bathytoma carpenteriana Gabb," DaU, Prof. Paper 59 U. S. Geol. Survey, p. 27, pi. 4, fig. 8, 1909. Bathytoma gabbiajia Dall, Prof. Paper 59 II. S. Geol. Survey, p. 28, pi. 4, fig. 1, 1909; Arnold and Hannibal, Proc. Amer. PhU. Soc, Vol. 52, p. 590, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916. Turris carpenteriana fernandoana Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 221, 1917. Cryploconns stearnsianus Raymond, DaU, Bull. 112 U. S. Nat. Mus., p. 68, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 62, 1927. Turris (Bathytoma) gabhiana Dall, Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 93, 1922. Pseudotoma remondii (Gabb), Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 422, pi. 31, fig. 5, 1926. Shell of small or medium size, biconic, short; whorls with a variable amount of angulation, some- times the angulation very slight, the whorls being hardly concave above and only moderately convex below, and the suture not far below the angle and inconspicuous so that the whorls merge into each other to form a smoothly conical spire, sometimes the angulation stronger as m S. carpenterianus variety tryonianus; sculpture of about ten low, widely spaced spiral cords on the body whorl usually with an intercalary between each pair and not infrequently a set of secondary intercalaries between these, the differentiation of the spirals becoming less distmct upwards until the differentiated spirals merge at the angle into the numerous uniform fine spiral threads of the concave area, growth lines moderately strong, and sometimes on the early whorls obscure axial riblets, about fifteen to the whorl; aperture a Uttle longer than half the length of the shell, lenticular, elongate, outer lip simple, with a wide, shallow posterior notch between the angle and the suture, columella smooth, shghtly flexuous, with a thin callus, anterior canal short, wide, not differentiated, slightly notched behind ; operculum with a termmal nucleus. Dimensions (of Recent figured specimen) : Altitude, 35 mm. ; length of aperture, 20 mm. ; dia- meter, 15 nun. Type specimens: Of remondii, at the Academy of Natural Sciences, Philadelphia; of fernandoanus, No. 165,303 in the U. S. National Museum; of stearnsianus, in the Ray- mond Collection, Berkeley, California. Type localities: Of remondii, Pliocene of Arroyo San Antonio, near Tomales Bay, just north of San Francisco, California; of fernandoanus. Pliocene, Graciosa Ridge, Santa Barbara, California; of stearnsianus. Recent, off San Diego. 496 San Diego Society of Natural History [ Memoirs Upper Miocene: Empire formation of Oregon (DaU, Arnold and Hannibal, Howe) ; Montesano formation of Washington (Weaver). Pliocene: Lower Pliocene, Elsmere Canyon (English) ; type locality of fernandoanus (Arnold) ; loc. 204 vS. D. S. N. H., Elsmere Canyon, Los Angeles County, one specimen (H. R. G.); loc. 207 S. D. S. N. H., Elsmere Canyon, Los Angeles County, one unusually large specimen (H. R. G.); loc. 216 S. D. S. N. H., east of Fernando Pass, Los Angeles County, two specimens (H. R. G.) ; loc. 227 S. D. S. N. H., south of the east end of the Santa Clara Valley, Los Angeles County, one specimen (H. R. G.); middle Pliocene, Merced formation (Gabb according to Dickerson); Etchegoin formation (Nom- land) ; loc. 217b S. D. S. N. H., Holser Canyon, north of the Santa Clara Valley, Los Angeles County, one specimen (H. R. G.). Pleistocene: Lower San Pedro "Saugus" of loc. 246 S. D. S. N. H. east of Timber Canyon, Ventura County, one specimen (U. S. G.). hiving: Monterey to San Diego (Dall). G abb's description of this species has been overlooked, partly because the species was assigned to a genus not belonging to this family, partly because the type was erron- eously said to come from the Miocene. The species includes individuals ranging in char- acter between two fairly well marked extremes, the comparatively smooth, conic form, and the more angulated form with sharper sculpture and usually riblets on the early whorls. The two extremes appear together in the upper Miocene, the former being figured by Dall (1909) as carpenterianus, the latter as gabbianus. Gabb had both forms in his original material, for his original figure and description are like those of fernandoanus Arnold, but Stewart's lectotype (selected as the type from the original material) is the same as stearnsianus. The smooth form alone has been found living, but it is rare and the discovery of the angulated form (which occurs in the Pleistocene) may be expected at any time. In view of the great difficulty of disentangling the two forms nomenclatorially and the probability that these variations are not genetically significant, appearing to- gether and living side by side so long, the attempt is not made here to separate them even as varieties. Their relationship is almost exactly analagous to that between carpenter- ianus and its variety or variational form tryonianus. The specimens recorded here from the S. D. S. N. H. localities are all somewhat angulated, the one from 207 being unusually large (altitude 57 mm., length of aperture 30 mm., diameter 25 mm.) but being dis- tinguishable from carpenterianus variety tryonianus by its short spire, the one from 227 being worn, so as to look like Dall's type of gabbianus, and the ones from 204 and 2176 being higher spired than is usual for this species, slightly suggesting a small S. riversianus (Ray- mond) or a sculptured Spirotropis fernandoensis (English), but their other characters show them to be merely unusual variants of this species. This species is interesting because the less angulated variations so closely resemble S. filosus (Lamarck), the type of Cryptoconus, practically the only distinguishing feature being the shallowness of the notch. It seems to be older than carpenterianus, which was probably derived from it during the Pliocene. Surc^dites {Megasurcula) keepi (Arnold)^ from the Temblor, middle Miocene, of Topanga Canyon, Los Angeles County, and of Barker's Ranch, Kern County, is another closely allied species. It is a short, broad, biconic species, with a sharp angulation (about two-thirds of the distance up the body whorl) surmounted by a row of sharp, rounded nodes, about twelve to a whorl, the sutures on the upper whorls coming approximately over the angulations of the preceding whorls, so that the spire is smoothly conical like that of the living rcmondii; the lower part of the body whorl is moderately convex, making the aperture broad; the posterior notch is much like that of rernondii; the columella is ■ Pleurotoma (Bathytoma) keepi Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 529, pi. 46, fig. 5, 1907, figure reproduced in Bull. 309 U. S. Geol. Survey, pi. 33, fig. 5, 1907. Balhyloma keepi Arnold, Smith, Proc. Calif. Acad. Sci., Ser. 4. Vol. 3, pp. 166, 175, 1912. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 497 nearly straight and stout, recalling that of Cancellaria tritonidea; the anterior canal is scarcely defined, slightly notched behind, the notch causing the fasciole that makes the columella irregular. This species is, however, clearly distinguishable from Temondii by the greater width of the area above the angle, and the shorter, broader aperture. Surculites ( Megasurcula) condonanus (Anderson and Martin) ' from the middle Miocene of Oregon is less easily distinguished, and may not be separable. It is small, short, has fewer (about twelve), stronger, more rounded nodes to the whorl. Surculites (Megasurcula) riversianus (Raymond) Pleuroloma (Genota) riversiana Raymond, Nautilus, Vol. IS, p. 14, 1904; Vol. 20, p. 39, pi. 2, fig. 9, 1906. Shell of medium size, very high spired; whorls moderately shouldered, the shoulder occurring on the spire whorls nearly two-thirds of the distance alcove the suture, witli a narrow, slightly concave area above it and an almost flat, convex area below; sculpture of sharp spiral threads, finer above the angle, crossed by growth lines of nearly equal strength; aperture defective. Dimensions (from Raymond) : Length of shell, 59 mm.; of aperture and canal, 30 mm.; of body whorl, 41 mm.; maximum diameter, 20.5 mm.; divergence, 30°. Type specimen: Probably in the Raymond Collection, Berkeley, California. Type locality: "Pliocene" of Santa Monica. Pleistocene: Type locality, only one specimen known. This peculiar specimen is characterized by its unusually high spire and the elevated position of its angulation. These two features, it will be noticed are really but a single character, for they are both due to the unusually high angle of gyration. Perhaps also the slenderness of the specimen is partl}^ exaggerated by the fact that the body whorl is broken ofT. So little is known about this form that it is hard to find its proper place in the classification, but it is probable that it should be assigned either to S. remondii or to S. carpenterianus as a variety or monstrosity. Surculites (Megasurcula) carpenterianus (Gabb) Plate 25, Figures 4a, 46 Pleiirotoma (Siircula) carpenteriana Gabb, Proc. Calif. Acad. Sci., Ser. 1, Vol. 3, p. 183, 186.5; Geol. Surv. Calif., Palseo., Vol. 2, p. 5, pi. 1, fig. 8, 1866; Merriam, List of Type Specimens at the Univ. of Calif., 1895. Surcula carpenteriana Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 72, 1868-9; Tryon, Man. Conch., Vol. 6, p. 239, pi. 7, fig. 3, 1884; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 266, in part, 1888; Keep, West Coast Shells, p. 57, fig. 41 (frontispiece and illustration on cover), 1888, 1892. Genola carpenteriana Gabb, Dall, Proc. U. S. Nat. Mus., Vol. 12, p. 303, 18S9. Pleuroloma {Dolicholoma} carpenteriana Gabb, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 207, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 202, 1903. Pleuroloma carpenteriana Gabb, Keep, West American Shells, p. 157, fig. 140, 1904. Pleuroloma (Genota) carpenteriana Gabb, Raymond, Nautilus, Vol. 20, p. 37, pi. 2, figs. 1, 3, not 2, 1906. ? Not Bathyloma carpenteriana Gabb, Dall, Prof. Paper 59 U. S. Geol. Survey, p. 27, pi. 4, fig. 8, 1909; = remondii. Bathytoma clarkiana Rivers, Bull. So. Calif. Acad. Sci., Vol. 12, no. 2, p. 29, unnvmibered plate, July, 1913; Nautilus, Vol. 28, p. 64, pi. 3, figs. B, C, Oct., 1914. Turris {Bathyloma) carpenteriana (Gabb), Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 203, 1916; Howe, Vol. 14, p. 93, 1922. Bathyloma carpenteriana Gabb, Martin, Univ. Calif. Publ. Geol., Vol. 9, pp. 231, 243, 255, 1916; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 343, pi. 37, fig. 6, 1918. Turris carpenteriana (Gabb), Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 221, 1917. Cryploconus carpenterianus Gabb, Dall, Bull. 112 U. S. Nat. Mus., p. 68, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Car.?on, Vol. 25, p. 49, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 63, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pseudotoma carpenteriana (Gabb), Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 423, 1926. ^ Bathytoma condtmana Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 89, pi. 7, fig. 8 {condoniana) , 1914. 498 San Diego Society of Natural History [Memoirs Shell large, high spu-ed, biconic ; whorls with a variable amount of angulation, sometimes almost smoothly rounded with hardly any concavity above the angle, sometimes with a strong angle sur- mounted by more or less distinct nodes, the mcrease in the size of the whorls usually somewhat ac- celerated as the shell approaches its full growth so that the outline of the spire is slightly concave and the young specimens are more slender than the adults, spiral sculpture of numerous cords varj'ing in strength as in remondii, crossed by more or less prominent growth lines ; aperture varymg in length from half to a little more than half the length of the shell, with practically the same features as those of remondii. This species goes through a series of variations analagous to those of remondii. It is distinguishable from remondii by its higher, more slender spire, and usually by its larger size. As pointed out above, it is probably a more recent split from the remondii stock, and the two may be hard to distinguish in the Pliocene. For this reason a number of the re- ported occurrences have to be questioned until specimens can be examined. This species does not range back so far as it was formerly thought to. Variety carpenterianus, s. s. Shell large, not heavy, high spired, biconic, without nodes or angulations, aperture relatively long. Dimensions (of large living specimen) : Altitude, 100 mm.; length of aperture, 55 mm.; diameter of body whorl, 37 mm. Type specimens: Of carpenterianus, at the University of California, No. 11,996; of clarkianus, cotypes, the larger, No. 10, and the smaller, No. 11, in the type collection of the San Diego Society of Natural History. Type localities: Of carpenterianus, "post-Pliocene" of Santa Barbara; of clarkianus. Pleistocene of Santa Monica. Pliocene: ? Lower Etchegoin formation (Nomland); ? San Diego well (Dall in Arnold, 1903); ? Merced and Purisima of middle California (Martin); Fugler's Point, Santa Barbara County (Carson), — specimens examined, typical; Coos conglomerate, Coos Bay, Oregon (Howe). Pleistocene: Las Posas zone, "Saugus" of Ventura Co. (from Arnold; Waterfall); lower Quaternary of Magda- lena Bay, Lower California (Jordan); Pleistocene of Santa Monica (Rivers); Pacific Beach, San Diego (Cooper; Arnold); upper San Pedro series, Palos Verdes, of San Pedro and vicinity (Arnold). hiving: Bodega Bay, California, to San Pedro (Dall). Surculites (Megasurcula) carpenterianus (Gabb) variety tryonianus (Gabb) Pleuroloma {Surcula) tryoniana Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 6, pi. 1, figs. 9, 9a, 1866; Merriam, List of Type Specimens at the Univ. of Calif., 1895. Surcula tryoniana Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 72, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mining Bureau, p. 266, 1888. Snrcula carpenteriana var. tryeniana Gabb, Baker, NautUus, Vol. 16, p. 41, 1902. Pleuroloma {Dolichotoma) tryoniana Gabb, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 203, 1903. Pleuroloma (Genola) tryoniana Gabb, Raymond, Nautilus, Vol. 20, p. 38, pi. 2, figs. 7, 8, 1906. Turris (Bathyloma) tryoniana Gabb, Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 203, 1916; Moody, Vol. 10, p. 44, 1916. Turris tryoniana (Gabb), Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 221, 1916. Cryptoconus tryonianus Gabb, Dall, Bull. 112, U. S. Nat. Mus., p. 68, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 61, 1927. Pseudotoma tryoniana (Gabb), Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 423, 1926. Shell like that of the typical form but somewhat heavier and with more strongly angulated whorls, the angle being accentuated by a row of small rounded nodes, about twelve to a whorl, aper- ture about half as long as the shell. Dimensions (of livmg specimen): Altitude, 87 mm.; length of aperture, 43 mm.; diameter of body whorl, 33 mm. Type specimen: At the University of California, No. 11,997. Type locality: "Post-Pliocene" of San Pedro. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 499 Pliocene: ? Jacalitos and lower Etchegoin, lower Pliocene (Nomland) ; ? Fernando formation, middle or upper Pliocene of Los Angeles (Moody) ; Santa Barbara horizon, upper Pliocene, of Santa Barbara (from Arnold). Pleistocene: Upper San Pedro series, Palos Verdes, of San Pedro (Arnold; probably also Gabb and Cooper). Living: San Pedro to Todos Santos Bay, Lower California (Dall). The variety iryonianus is like the form fernandoanus of remondii in that it is more shouldered, and it has a tendency to form nodes, as the latter has to develop riblets. It is further like the varieties of remondii in that it is probably of no significance, but un- like them it has always been clearly separated. The separation is preserved here princi- pally for descriptive purposes and because it is easy to make. The intermediate speci- mens are more common than the tryonianus extreme. SurcuHtes (Megasurcula) carpenterianus (Gabb) variety tremperianus (Dall) "Pleurotoma {Genola) carpenteriana Gabb," Raymond, Nautilus, Vol. 20, p. 38, in part, pi. 2, fig. 2 only, 1906. Bathyloma tremperiana Dall, NautUus, Vol. 24, p. 109, 1911. Cryptoconus tremperianus Dall, Bull. 112 U. S. Nat. Mus., p. 68, pi. 12, fig. 5, 1921; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 1, p. 62, pi. 11, fig. 12, 1927. Shell like that of the typical variety but heavier and with the increase in the size of the later whorls not accelerating, so that the body whorl is relatively smaller than in the typical variety and the aperture relatively shorter. Dimensions (of Pleistocene specimen) : Altitude, 59 mm.; length of aperture, 28 mm.; diameter of body whorl, 19 mm. This specimen is extreme. Type specimen: In the U. S. National Museum. Type locality: Off San Pedro, California {fide Oldroyd). Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California (Jordan); upper San Pedro series, Palos Verdes, of San Pedro (Arnold Collection). Ldmng: Point Ano Nuevo, middle California, to Cedros Island, Lower California (Dall). Like tryonianus, this variety is probably of little or no significance. It may be eco- logic, living in exposed positions; or, as Mrs. Oldroyd remarks, it may be partly patho- logic, most of the specimens showing signs of having been injured. It is very close to two earlier named forms: clarkianus Rivers, which although narrow and high spired, is here included with the typical variety because of its longer aperture; and cooperi Arnold, which has the short aperture and thick shell but has a sharper shoulder. The variety cooperi is a rare extreme of this type of variation and it is very probable that tremperianus should be classed as a synonym of it. Surculites (Megasurcula) carpenterianus (Gabb) variety cooperi (Arnold) Plate 25, Figure 3 Plturotoma {Dolichotoma) cooperi Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 203, pi. 7, fig. 3, 1903. Pleurotoma (Genota) cooperi Arnold, Raymond, Nautilus, Vol. 20, p. 38, pi. 2, fig. 10, 1906. Shell like that of the typical variety but heavier, with a shorter aperture and a sharp shoulder, the area above the shoulder being strongly concave, and the shoulder (on the type specimen at least) surmounted by small mdistmct nodes about fifteen to the whorl, practically obsolete on the body whorl. Dimensions (of type) : Altitude, 64 mm. ; length of aperture, 32 mm. ; diameter of body whorl, 24 mm. Type specimen: In the Stanford University type collection, No. 426. Type locality: Upper San Pedro series, Palos Verdes, of San Pedro, only the type found. 500 San Diego Society of Natural History [Memoirs Pliocene: ? Loc. 202m, S. D. S. N. H., basal Pliocene of Elsmere Canyon, Los Angeles Co., one specimen (H. R. G.). Pleistocene: Type locality; Pleistocene of Santa JNIonica, Rivers Collection, one sjiecimen (Raymond). The nodes on the type specimen of this variety are more numerous and smaller than those on the variety tryonianus, and the angle is sharper, but the type is an extreme specimen. The specimen figured by Raymond shows how close this variety is to the others. It is most probable that the variety tremperianus should be treated as a synonym. The specimens reported by Nomland from the Etchegoin as tryonianus may be cooperi, and the specimen recorded above from loc. 202 may belong to either variety. Surculites {Surculites) ivynootcheensis (Weaver), a Miocene fossil from Washington, is so strikingly similar to cooperi in its general characters, and also to *S. {P seudotoma) intortus (Brocchi), the type of the subgenus P seudotoma, that it is here figured (plate 25, figure 2) side by side with the others to show the relationship. There can be little doubt that all three belong to the same genus. Subgenus PSEUDOTOMA Bellardi, 1875 Pseudoloma Bellardi, Bull. Societa Malac. Ital., Vol. 1, p. 20, 1875; Mem. R. Accad. Sci., Torino, Ser. 2, Vol. 29, pp. 209-222, 1878; Cossmann, Ess. Pal^o. Comp., Vol. 2, p. 145, 1896; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 423, in part, 1926. Type (by monotypy), Murex {Pleurotoma) intortus Brocchi, figured by Bellardi, Mem. R. Accad. Sci., Torino, Ser. 2, Vol. 29, p. 214, pi. 7, fig. 10, 1878; by Cossmann, Ess. Paleo. Comp., Vol. 2, pi. 8, fig. 11, 1896; and by Harmer, Mon. Palseo. Soc, Vol. 68, Pho. Moll. Gt. Brit., Vol. 1, p. 212, pi. 26, figs. 11-14, 1915; also figured here, plate 25, figures la, 16; Oligocene to upper Pliocene of Europe (Harmer). Shell of variable size and shape, the type species being large and turreted, practically indis- tinguishable from typical Swcidites except that the whorls are slightly more mflated, the angles more rounded, and the area above the angle slopmg concavely upward instead of having a tabulation sharply marked off from a vertical sutural collar; other variations of Pseudoloma lacking the angle almost entirely and grading into Cryptoconus. Geologic range: Eocene to Recent of Europe; Eocene of Australia (fide Cossmann). Bellardi has described and figured in his monograph of Pleurotomas, 1878, a series of species of Pseudotoma from the Italian Miocene that vary in form from the large, strongly shouldered, conspicuously nodose intorta to the small, round-whorled, smooth Iceins (erroneously taken as type by Cossmann). In the same collection is another species that is almost surely a Clinura, "P." bonellii. Between these three extremes are a number oi representatives of intermediate stages. Cossmann and Pissarro figure in their "Icono- graphie complete des Coquilles fossiles de I'Eocene des Environs de Paris," Vol. 2, pi. 49, 1907-1913, a similar series of species of Cryptoconus and a few which they assign to Pseudotoma. Although there do not happen to be in this Eocene series any species that have quite so much of a shoulder as intortus, there are some with deep notches that are as large and have the same form (except for the notch) as some of Bellardi's species that are intermediate between the extremes Icevis and intortus; and there are some species of the size and shape of C. filosus that are assigned by Cossmann and Pissarro to Cryptoconus but have a shallow notch, and there are some with notches of intermediate depth. This kind of intergradation can be found between most of the subgenera of Surculites, and this is the reason why it is not thought desirable to separate these groups generically. The nature of the relationship between Pseudotoma and Megasurcula is not quite clear. The two may be parallel offshoots from the Eocene Surculites stock; or Pseudotoma Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 501 may have been derived from a portion of the stock close to the typical form and Mega- surcula directly from Clinura. The latter supposition is the more probable. The species reported by Cossmann (1896) from the Claiborne, Eocene of Alabama, as Pseudotoma is more probably a Megasurcula, if the two subgenera can be distinguished at all. Subgenus CRYPTOCONUS von Koenen, 1867 Cryploconus von Koenen, Palaeontographica, Vol. 16, p. 167, Sept., 1867, list includes Pleurotoma filosa Lamarck (p. 169) and several other species; Arch. Naturg., Vol. 2, p. 211, 1880; Cossmann, Ann. Soc. Roy. Malac. Belg., Vol. 24, p. 235, 1889, Pleurotoma filosa Lamarck designated as type; Ess. Pal6o. Comp., Vol. 2, p. 147, 1896; Dall, Proc. V. iS. Nat. Mus., Vol. 54, pp. 319, 325, 1918, in part. Type (by subsequent designation, Cossmann, 1889), Pleurotorria filosa Lamarck, Eocene of Europe, figured by von Koenen, Palaeontographica, Vol. 16, pi. 11, fig. 8, 1867, by Cossmann, Ess. Paleo. Comp., Vol. 2, p. 148, pi. 7, figs. 20-21, 1896, and by Cossmann and Pissarro, Icon. Comp. Coq. Eos. Env. Paris, Vol. 2, pi. 49, figs. 216-1, Paris, 1907-1.3. Shell of medium size, biconic, shoulders obscure, body whorl rounding down m a smooth curve to the base, notch rounded but narrower and deeper than in the typical and the other subgenera of Surculites, a little distance below the suture, spiral sculpture sometimes present on the fasciolar area as well as over the rest of the whorl, fasciolar area narrower than in the other subgenera, anterior canal short, poorly defined, merely a continuation of the Conws-Hke aperture. Geologic range: Eocene and Oligocene of Europe. Cryptoconus is difficult to separate from two groups, besides typical Surculites, that have older names : Coyiorbis Swainson^ and Genota H. and A. Adams. Von Koenen explains fully how to distinguish it from the former, and Cossmann (1896) summarizes his argu- ment. In Conorbis all of two shell layers and part of the third in the interior parts of the upper whorls are resorbed as in Conus, and there is a slight difference in the shape of the columella. Hence Co7wrbis is generally classed with the Conidw, although in external form it is practically identical with Cryptoconus. The writers have not been able to ex- amine Conorbis dormitor, but they assume that this distinction is significant. It is ex- plained below that Genota is distinguished by its notch, which is situated on or near the shoulder and is sharper and more triangular in shape. The notch of Cryptoconus retains to a greater extent than do the notches of the other subgenera of S2irculites the form of the notch of the ancestral Turricula. Cryptoconus is probably closely related to the ancestors of Genota. It is easily distinguishable from the typical Surculites by its much weaker angle and its deeper notch, but it is less easily dis- tinguishable from the intermediate subgenera, Clinura and Pseudotoma. The writers be- lieve that Dall was correct in classifying the California living and later Tertiary species in the same genus as Cryptoconus, and his precedent in using Cryptoconus as a genus name for those species is not followed here only because of the discovery of an earlier name be- longing to the same generic gi'oup. Pseudotoma is later than Cryptoconus and can only be distinguished subgenerically by the slightly shallower notch and wider fasciolar area. Even this separation may not be worth while to maintain, for the two intergrade com- pletely in the early Tertiary of Europe. As pointed out by Dall, the smaller living Pacific coast species now assigned to Megasurcula, S. remondii (Gabb), (formerly known as stearnsianus Raymond), has practically the same shape as S. filosus (Lamarck), which it resembles, except for the shallower' notch, much more closely than it does the type of Pseudotoma. 1 Conorbis, Swainson. Treat. Malac, p. 312. 1840. type (by monotypy) C. dormitor Sowerby. See also Melvill, Proc. ^fmsensis Waterfall, L^niv. Calif. Publ. Geol., Vol. 18, p. 86, pi. 6, figs. 2, 3, 1929. Shell with the sulssutural band distmct, nodes sometimes somewhat elongated, more like the eostse of penicillata. Dimensions (from Carpenter): Length, .6 mch.; length of spire, .32 inch; width, .28 inch; angle, 38°. Type specimens: Of aurantia, in the U. S. National Museum; of somisensis, at the University of California. Type localities: Of aurantia, San Diego, living; of somisensis, lower Pleistocene of Ventura County. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 563 Pleistocene: Type locality of somisensis. Liinng: Monterey to Mazatlan, Mexico (Oldroyd). This variety is probably hardly worth distinguishing, but is kept to emphasize the fact that the subsutural band is sometimes distinct in this species, helping to show the relationship with the more southerly P. penicillata. It will be noticed that this variety, which is more closely related to penicillata, has a more southerly distribution than has the typical variety. Pseudomelatoma fleenerensis (Martin) Drillia fleenerensis Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 193, pi. 22, fig. 5, 1914. Shell of medium or small size, sculptured with about 14 elongate, slightly oblique costse, like P. ■penicillata except that the anal fasciole lies directly below the suture and the subsutural band of nodes is obsolete as m P. torosa, s. s., and also, the outline of the whorls is more rounded than in penicillata, and the imier lip appears to be better defined. Dimensions (from Martin) : Altitude of the type, apex defective, 31 mm. ; maximum diameter of the shell, 10.5 mm.; length of the aperture, 9.5 mm.; length of the canal, 3 mm.; apical angle, 25°. Type specimen: At the University of California. Type locality: Upper part of the Wildcat series, one mile south of Centerville, Hum- boldt Co. (U. C. loc. 1860). Upper Pliocene: Uncommon, known only from the type locality (Martin). It is not unlikely that this form is just another one of the connecting links between P. penicillata and P. torosa. On the other hand, the curvature of the whorls makes it more the shape of the form merriami of Borsonia bartschi (Arnold), which is distinguished merely by its deeper notch close to the suture and its short node-like costse. If the pos- sibility of variation in fleenerensis be recognized as in the peyiicillata-torosa series, it can be seen that fleenerensis might be another variety of bartschi; and this possibility helps to show, as mentioned above, how difficult it is to separate Pseudomelatoma from the various genera to which it is closely related. Martin compared ^eencreras/s with Clavus {Cymato- syrinx) johnsoni Arnold, but the shape of the aperture and the armed notch of the latter (poorly shown in Arnold's figure), as well as the sculpture, indicate that the two species are onh' distantly related. Subgenus LAEVITECTUM Ball, 1919 Lsevitectum Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 19, 1919. Type (by monotypy), Drillia eburnea Carpenter. Shell like that of typical Pseudomelatoma, but with sculpture only on the earliest whorls, or en- tirelj' lacking. This subgenus or section is distinguished from Spirotropis by its smaller notch, closer to the suture, and perhaps also by a heavier shell. Spirotropis (Antiplanes) lita (Dall) and S. (A.) bulimoides (Dall) are forms showing the connection between this group and Antiplanes, and it is possible that the former would be more appropriately classified here. 564 San Diego Society of Natural History [ Memoirs Pseudomelatoma (Laevitectum) ebumea (Carpenter) Not Pleurotoma eburnea Bonelli, 1842. Drillia eburnea Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 668, 1864, reprinted in Smithsonian Misc. Coll., No. 252, p. 154 (bottom pagination), 1872; Proc. Zool. Soc. London, p. 280, 1865, reprinted in Smithsonian Misc. Coll., No. 252, pt. I, p. 273 (bottom pagination), 1872. "? Clathrodrillia" (Lxiyitedum) eburnea Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 19, pi. 13, fig. 5, 1919. Shell like the coarser, thicker shelled variations of Psexidomelatoma penicillata, but with sculpture consisting of axial ribs, on only one or two of the earliest whorls of the spire. Dimensions (from Carpenter): Length, 1.3 in.; length of spire, .8 m.; width, .45 m.; angle, 30°. Type specimen: No. 22,817 in the U. S. National Museum. Type locality: ? Gulf of California. This species is very interesting, showing the relation between these smooth forms and the more sculptured Pseudomelatomas. It may be only an unusually smooth speci- men of penicillata, for a number of forms of penicillata have several of the whorls of the spire, as well as the body whorl, smooth. Genus MELATOMA Swainson, 1840 Melaloma Swainson, Treat. Malac, pp. 202, 342, 1840; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 317, 1918. ;' Clionella Gray, Proc. Zool. Soc. London, p. 153, 1847, t>-pe (by original designation) Buccinum sinuatum Born, 1778, illustrated by Chemnitz, Neues Syst. Conchyl. Cab., Vol. 4, p. 307, pi. 155, fig. 1464, 1780, under the name Boletus Itii'binatus, the figure being referred to by Born in the Test. Mus. Cses. Vind., p. 268, 1780, also figured by Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 8, species 68, as buccinoides Lamarck, and by Tryon, Man. Conch., Vol. 6, p. 233, pi. 9, fig. 50, 1884, livfng. South Africa; Iredale, Proc. Malac. Soc. London, Vol. 13, p. 32, 1918. Type (by monotypy), M. costata Swainson, Treat. Malac, p. 342, fig. 104, 1840, said by Swainson on the authority of Rafinesque to have been collected in the Ohio River, but Dall thinks otherwise. Distribution: South Africa (?). Swainson's figure resembles Pseudomelatoma penicillata var. moesta more than it does Clionella sinuata (Born), so it is to be wondered on what evidence Dall based his iden- tification of Melatoma with Clionella. Perhaps Iredale is right in advising the use of Clionella for the South African gxoup. Clionella has a short, almost Terebra-like aperture, with a deeply notched, very short, undefined anterior canal. Melatoma costata Swainson has an elongate aperture, fully half as long as the shell, and the anterior canal is not notched. The sculpture of both is like that of Pseudomelatoma penicillata. Among the species assigned to Clionella by Tryon is Pleurotoma sigillata Reeve from South Africa, which is so much like Moniliopsis gracio- sana (Arnold) that it is somewhat of a question whether the latter should not be assigned to Clionella, perhaps with Moniliopsis as a subgenus. Genus MONILIOPSIS Conrad, 1865 Moniliopsis Conrad, Amer. Journ. Conch., Vol. 1, p. 143, 1865; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 317, 1918. Type (by monotypy), Pleurotoma elaborata Conrad, Fos. Sh. Tert. Form., Ed. 1, no. 4, p. 46, October, 1833; Ed. 2, no. 3, p. 52, pi. 17, fig. 19, 1835, republished by G. D. Harris, Washington, 1893; Eocene, Claiborne, Alabama. Shell of medium size, of medium weight or tliin, spire high; protoconch smooth, of about two whorls, the rest of the shell sculptured with finely incised spiral lines about equal in prominence to the elevated growth lines which zigzag across the anal fasciole and gently curve over the lower part of Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 565 the body whorl, growih lines about half as wide as their interspaces; aperture lenticular, approxi- mately a third the length of the shell, outer lip thin, smoothly curving, with a shallow triangular notch about a quarter of the way down from the suture, inner lip defined as the area on which the sculpture of the body whorl has been resorbed, body whorl curving in abruptly near the middle of the columella, columella varying in length, sometimes nearly straight, sometimes moderately twisted, in the latter case a short anterior canal often distinctly defined by the bending in of the outer lip, anterior canal with a broad, shallow notch behind; operculum horny, with a terminal nucleus. Geologic range: Eocene to Recent. Distribution: Puget Sound to Lower California. This genus is very closely allied to Pseudomelatoma, with which it intergrades, and the latter might well be considered a subgenus. Pseudomelatoma is distinguished by its heavier shell, its stronger axial sculpture, and its straight columella. Apparently the more recently named Clathrodrillia, with which Dall classed Moniliopsis and which is here con- sidered a subgenus of Claims, is only distantly related, being shown by its armored aper- ture to belong to the Claims branch of the family. The figure of the type species of Moniliopsis is, as Dall remarks, very poor, and ap- parently it does not show the full view of the aperture. A small living specimen of M. incisa, if turned slightly to the right, resembles very closely Conrad's type figure, except that the columella on the latter is shorter and the sculpture is inadequately represented. Moniliopsis grippi Dall Mmiliopsis grippi Dall, Proc. U. S. Nat. Mus., Vol. .56, p. 27, pi. 8, fig. 2, 1919. Clathrodrillia (Moidliopsis) grippi Dall, Bull. 112 U. S. Nat. Mus., p. 69, 1921; 01droyd«, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 72, pi. 11, fig. 15, 1927. Shell having the shape of Pseudomelatoma, though smaller and more delicate ; early whorls sculp- tured with 14 or 15 strong, roimded ribs and a corresponding row of nodes above the anal fasciole as in Pseudomelatoma, s. s., all whorls sculptured with revolving incised lines as in Moniliopsis incisa, the Imes passing over the ribs of the early whorls ; columella straight, aperture broad, rounding an- teriorly as in Pseudomelatoma, anterior canal not defined. Dimensions: Altitude, 27 mm.; altitude of last whorl, 16 mm.; diameter, 10 mm. Type specimen: No. 203,670 in the U. S. National Museum. Type locality: San Diego, California, living, known only from the type locality. This species is very interesting, for it bridges the gap between Moniliopsis and Pseudomelatoma. The strength of the spiral sculpture and the more delicate construction of the shell place it here rather than in Pseudomelatoma. Lora levidensis (Carpenter) resembles this species except that it lacks the nodes above the anal fasciole, and the colum- ella and outline of the body whorl are more flexuous. The operculum of levidensis has a terminal nucleus, as is normal for Moniliopsis, and if it should ever be found that that species belongs to Moniliopsis, grippi might be a variety of it. Moniliopsis grippi should not be confused with Dall's "Lora" grippi, which is probably a Bellaspira. Moniliopsis incisa (Carpenter) Plate 20, Figure 21 Drillia incisa Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 603, 657, 1864, reprinted in Smithsonian Misc. Coll., No. 252, pp. 89, 143 (bottom pagination), 1872; Proc. Acad. Nat. Sci., Phila., p. 62, 1865; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 239, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 205, 1903; Keep, West American Shells, p. 160, 1904. Drillia cancellata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 603, 658, 1864, reprinted in Smithsonian Misc. Coll., No. 252, pp. 89, 144 (bottom pagination), 1872; Proc. Acad. Nat. Sci., Phila., p. 63, 1865; Tryon, Man. Conch., Vol. 6, p. 183, 1884; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 204, 1903; not Drillia cancellata J. Sowerby, 1827, etc. 566 San Diego Society of Natural History Memoirs Turris (Surciila) rhiiics Dall, new name for Drillia cancellata Carpenter, Proc. U. S. Nat. Mus., Vol. 34, p. 248, 1908. Moniliopsis rhines Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 28, pi. 8, fig. 5, 1919 (young). Moniliopsis incisa Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 28, pi. 12, fig. 7, 1919. Turris incisa Carpenter, Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 342, pi. 41, figs. 2a, 26, 1918. Clathrodrillia (Moniliopsis) incisa Carpenter, Dall, Bull. 112 U. S. Nat. Mus., p. 70, 1921; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 75, pi. 18, fig. 3 (4 on plate), 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 72, pi. 18, fig. 3, 1927. Clathrodrillia (Moniliopsis) rhines Dall, Bull. 112 U. S. Nat. Mus., p. 70, 1921; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 76, pi. 5, fig. 4, 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 74, 1927. Shell conforming closely to the generic description, of eleven or twelve whorls when adult, each whorl with 20 to 25 sjiiral, incised lines, about half as wide as the flat-topped interspaces and with 30 to 40 raised growth lines of varying strength of development. Variety incisa, s. s. Shell of moderate size and weight, with comparatively strongly convex, evenly roimded whorls and a fairly short columella, with the mmimum number of spiral grooves and, except on the young or on unusually well-preserved specimens, almost mdistinguishable growth lines. Dimensions : Altitude, 25 mm. ; length of aperture, 1 1 mm. ; diameter, 8 mm. Type specimens: At the Academy of Natural Sciences, Philadelphia ?. Type locality (for both names) : Puget Sound. Pleistocene: "Saugus," lower San Pedro series. Las Posas formation, of loc. 233 north of Arroyo Santa Rosa, Ventura Co., six specimens (U. S. G.) ; loc. 247 north of city of Ventura, Ventura Co., one specimen (U. S. G.),'loc. 249 north of city of Ventura, Ventura Co., five specimens (U. S. G.); Santa Barbara (Cooper) ; San Pedro, upper and lower horizons (Arnold) ; San Diego (Arnold) ; upper San Pedro of Santa Monica. Litring: British Columbia, Puget Sound, and an undetermined distance southward, probably not so far as it is commonly reported (San Pedro or San Diego). The typical variety of this species is characteristic of the northern part of the range. The shells are usually heavier and have a rougher surface than the more southerly var- ieties, and only on young specimens like those known under the name of rhines does the delicate cancellate sculpture typical of Moniliopsis appear. The northern specimens as- signed to M. halcyonis by Dall and Oldroyd probably also belong here. Moniliopsis incisa (Carpenter) variety ophioderma (Dall) Pleuroloma inermis Hinds, Proc. Zool. Soc. London, p. 37, 1843; Zool. Voy. Sidphiir, Mollusca, p. 16, pi. 5, fig. 8, 1844; not Pleiirotoma inermis Partsch, (1842) 1843. Drillia inermis Hinds, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 330, 1857; Rept. for 1863, pp. 537, 541, 584, 657, 683, 1864, reprinted in Smithsonian Misc. Coll., No. 252, 1872; Gabb, Geol. Surv. Calif., Pala!o., Vol. 2, p. 72, 1868-9; Tryon, Man. Conch., Vol. 6, p. 182, pi. 12, figs. 40, 43, pi. 32, fig. 42, 1884; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 239, 1888. Pleuroloma {Clionella ?) "peniciUala Carpenter," Weinkauff, Syst. Conch. Cab., Pt. 238, p. 125, pi. 28, figs. 1, 4, 1876. "Drillia penicillaia Carpenter," Tryon, Man. Conch., Vol. 6, p. 182, pi. 12, fig. 40, 1884; Keep, West Coast Shells, p. 56, fig. 38, 1888; West American Shells, p. 159, fig. 144, 1904. Not "Drillia inermis Hinds," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 205, pi. 5, fig. 10, 1903, = variety /one/; era Dall. Drillia inermis "var. penicillaia Carpenter," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 205, 1903. Turris (Surcula) ophioderma Dall, new name for Pleuroloma inermis Hinds, Proc. U. S. Nat. Mus., Vol. 34, p. 247, 1908. Moniliopsis ophioderma Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 28, pi. 12, fig. 5, 1919. Clathrodrillia (Moniliopsis) incisa ophioderma Dall, Bull. 112 LT. S. Nat. Mus., p. 70, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 73, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Clathrodrillia ophioderma Dall, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Not Moniliopsis incisa "ophioderma Dall," Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, .\rt. 22, p. 10, 1925. Clathrodrillia incisa ophioderma Dall, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 567 Like the tj'pical variety, but with slightly larger, thinner shell, with somewhat more flattened, elongate whorls, with weaker spiral grooves but stronger axial sculpture, and with reddish-brown color markings instead of greenish-gray. Dimensions: Altitude, 47 mm.; length of aperture, 18 mm.; diameter, 13 mm. Type specimen: Whereabouts unknown. Type locality: Unknown. Pleistocene: Upper and lower San Pedro of San Pedro, etc., San Diego, and Ventura (Arnold); Magdalena Bay and San Quintin Bay, Lower California (Jordan); "Saugus" of Ventura Co. (Waterfall). Living: Bolinas Bay, California, to Ballenas Lagoon, Lower California (Dall). Carpenter reports D. inermis or a related species living in Japan, but no later record of such an occurrence has been found. The variety ophioderma is the common form in California. It is distinguished from the variety /anc/ieroB by the more flattened outline of the whorls. Infancherce the whorls are strongly convex in the middle, abruptly contracted below, and often slightly concave above, whereas in ophioderma the whorls are nearly flat in the iniddle and are full above the fasciole, recalling in some respects the typical form of Perrona. The height of the spire varies considerably. Moniliopsis incisa (Carpenter) varietj' fancherae (Dall) •'Drillia inermis Hinds," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 205, pi. 5, fig. 10, 1903. Mayigiliafanchers; Dall, Proc. Biol. Soc. Wash., Vol. 16, p. 172, 1903. Turris {Snmda) halcyonis Dall, Proc. U. S. Nat. Mus., Vol. 34, p. 248, 1908. "Tunis {Drillia) inermis (?) Hinds," Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 44, 1916. Turris {Drillia) modestus Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 54, pi. 1, fig. 8, 1916. Moniliopsis fanchers Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 28, pi. 8, fig. 3, 1919. Moniliopsis halcyonis Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 29, pi. 8, fig. 1, 1919. Clathrodrillia {Moniliopsis) Sancherys Dall, Bull. 112 U. S. Nat. Mus., p. 70 (pi. 6, fig. 3 ?), 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 74, pi. 19, fig. 8 (pi. 3, fig. 4 ?), 1927. Clathrodrillia {M (miliopsis) halcyonis Dall, Bull. 112 U. S. Nat. Mus., p. 70, 1921; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 76, pi. 18, fig. 1, 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 73, pi. 7, fig. 2, pi. IS, fig. 1 (same figure), 1927. Borsonella polynotata Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 158, 1924, imnecessary new name for modestus. Moniliopsis incisa "ophioderma Dall," Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 10, 1925. Shell like that of the typical variety but v.ith more strongly convex whorls curving m abruptly below the middle and making the columella more slender, the upper part of the whorls often shghtly concave, the sculpture stronger and more distmct, the color dark brownish. Dimensions: Altitude, 23 mm.; length of aperture, 10 mm.; diameter, 7 mm. Type specimens: Oi fancherae, No. 109,303, of halcyonis, No. 110,644, in the U. S. National Museum; of modesta-polynotata, at the University of California. Type localities: Oi fancheroe, near Avalon, Catahna Island; of halcyonis, Coronado Beach, San Diego; of modesta-polynotata, upper Pliocene, Fourth and Broadway, Los Angeles. U. Pliocene: Fourth and Broadway, Los Angeles (Moody). Pleistocene: Upper San Pedro of San Pedro (Arnold; Oldroyd, 1925). Liinng: Santa Rosa Island, California, to Point .\breojos. Lower California (Dall). The northern reports of halcyonis appear to be erroneous. The varieties of incisa seem to have an ecologic significance, but they grade into each other so completely that they probably belong to the same specific stock. Just as rhines is probably the young of incisa, s. s., so fancherce is probably the young of halcyonis. If further study should show that halcyonis is separable from fancherce, the references to the latter should include only those in which the name fancherce was used, and only part of 568 San Diego Society of Natural History [Memoirs those. Some young halcyonis have surely been mixed in, and the second shell illustrated by Dall as fancherce may not belong even to the genus. The size, height of spire, and strength of sculpture vary in this variety as in the others. Moniliopsis incisa (Carpenter) variety quinquecincta, new variety Plate 26, Figure 33 Shell of relatively small size, moderately solid, of five whorls plus probably three or four more in the apex, which is missing on the type, high-spired; whorls evenly convex, body whorl curving in abruptly below the middle as in the variety fancherce, spire whorls sculptured with about five strong, squarish, revolving cords, about half as wide as the mterspaces, body whorl with seven or eight more, equally strong, similarly spaced cords, growi;h Imes crossing the cords as m fanchercE but weaker and obscured in the type specimen by weathering; columella shorter than m fancherce and somewhat twisted, though defective; aperture also shorter and without a well-defined anterior canal. Dimensions: Altitude (apex missing), 20 mm.; length of aperture, 7 mm.; diameter, 6 mm. Type specimen: No. 247 in the collection of the San Diego Society of Natural History. Type locality: Basal Pliocene of Elsmere Canyon, Los Angeles County. Pliocene: Known only from the type locality, loc. 207 S. D. S. N. H., Elsmere Canyon, Los Angeles County, one specimen (H. R. G.). The shape and the size of this variety recall the variety fancherce except for the col- umella and the shorter aperture. The predominance of the spiral sculpture recalls the variety incisa, s. s., but the relative width of cords and grooves is reversed and the cords are fewer in number. This variety may be, or may represent, the ancestor of the others. This form is similar to Asihenotoma (Endiaioma) quadricincta (Cossmann), but lacks the columellar plait mentioned by Cossmann in his description. ' It is not unlikely that Endiatoma should be considered a subgenus of Moniliopsis. Moniliopsis briseis (Dall) .' Turris {Antiplanes) diavlax Dall, Proc. U. S. Nat. Mus., Vol. 34, p. 247, 1908. Antiplanes briseis Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 35, pi. 32, fig. 1, 1919; Bull. 112 U. S. Nat. Mus., p. 72, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 85, 1927. ? Antiplanes diaulax Dall, Bull. 112 U. S. Nat. Mus., p. 71, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 84, 1927. SheU like that of M. incisa variety /a nc/iero" but with the sculpture nearly obsolete. Type specimens: Of diaulax, No. 110,609, of briseis, No. 212,329, in the U. S. National Museum. Type locality : Coronado Islands, near Mexican boundary, known only from the type locality. This species (or it may be another variety of incisa) is interesting because it bridges the gap between Moniliopsis and Spirotropis and helps to illustrate how closely the two groups are related. It still retains enough of the sculpture so that it is more appropriately placed in Moniliopsis. The form diaulax has never been figured, but from the description it appears to be the same. If it is, the name diaulax should be used instead of briseis. The types come from the same place. 1 Ess. PaWo. Comp., Vol. 2, p. 106. pi. 6, fig. 30, 1896. Volume 1 1 PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 569 Moniliopsis graciosana (Arnold) Plate 26, Figures 12, 13 Drillia graciosana Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 12, pi. 54, fig. 18, 1907, figure reprinted in Bull. 322 U. S. Geol. Survey, pi. 21, fig. 18, 1907. Shell of medium size, of variable weight, spire elevated; whorls angulated a little above the middle of the spire whorls, concave above, convex below, sculptured with axial riblets, 17 to 19 to a whorl, fairly strong and sloping obliquely forward on the periphery, weaker and sloping obliqueh- backward above the angle, more or less obscure on the body whorl, and not ex-tending below the per- ipheral band, spiral grooves crossmg the riblets, one to three aljove the angle, strong, equal to or narrower than the intervening bands, one or two very famt on the periphery, usually visible on the spire whorls only, and nme to eleven below the peripheral band on the body whorl, strong, usually much narrower than the intervening bands but sometimes of approximately equal width, only one or two showmg on the spire whorls; aperture about two-fifths the length of the shell, ovate, outer lip simple, with a moderately deep, rounded notch on the periphery, inner lip usually more or less strongly incrusted, Init sometimes partly resorbed, columella short, twisted, anterior canal short, with a shallow notch Ijehind, sometimes leaving a well-marked siphonal fasciole. Dimensions (of figured specimen); Altitude, 28 mm.; latitude, 12 mm.; length of aperture, 12 mm. Type specimen: In the U. S. National Museum. Type locality: Pliocene of Graciosa Ridge, Santa Barbara Co. This species is distinguished from M. incisa (Carpenter), which has a similar notch, similar general shape, and similarly incised gi-ooves, by its somewhat more stumpy form and its axial riblets. It is distinguished from Turris cingulifera (Lamarck), to which it bears a remarkable resemblance, by its shallower notch, its shorter spire, and its axial riblets. It helps to link Moniliopsis with Turris and Hemipleurotoma. It is also similar in appearance to Pleurotoma sigillata Reeve (Conch. Icon., Vol. 1, Pleuroto^na, pi. 40, species 363, 1846), which Tryon says comes from South Africa. Variety graciosana, s. s. Shell solid, with a comparatively wide concave area above the anal fasciole sculptured with two or three spiral Imes ; columella shorter, more twisted in the adult, anterior canal shorter, more conspicuously notched in the adult. Pliocene: Type locality only. Moniliopsis graciosana (Arnold) variety mercedensis (Martin) Plate 26, Figure 30 Drillia mercedensis Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 194, pi. 22, figs. 2a, 26, 2c, 1914; Vol. 9, pp. 229, 230, 231, 233, 239, 243, 257, 1916; Nomland, Vol. 10, p. 221, 1917. Turris (Drillia) mercedensis (Martin), Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 44, pi. 2, figs. 7a, 7b, 1916. Clathrodrillia diegensis Oldroyd, Nautilus, Vol. 34, p. 115, pi. 5, fig. 12, 1921. Clathrodrillia (Moniliopsis) mercedensis Martin, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, pp. 77, 78, 79, 1929. Shell like that of the typical variety but thinner, with a narrower concave area above the anal fasciole and frequently only one spiral groove in this area; columella longer, slenderer, straighter, anterior canal longer, narrower. Dimensions: Altitude, 28 mm.; length of aperture, 12 mm.; diameter of bodj' whorl, 11 mm. Type specimens: Both at the University of California. Type localities: Of mercedensis, Merced series, Pliocene, near Santa Rosa, north of San Francisco Bay; of diegensis, upper Pleistocene of Pacific Beach, San Diego. 570 San Diego Society of Natural History [ Memoirs Pliocene: Merced and Purisima formations of middle California in a number of localities, and the Wildcat formation of northern California (Martin); Etchegoin of the Coalinga district (Nomland); upper Pliocene of Los Angeles (Moody); upper Pico of Ventura Co. (Waterfall). Pleistocene: Lower San Pedro series, "Saugus," Las Posas formation of loc. 233, S. D. S. N. H., north of Arroyo Santa Rosa, Ventura Co., southern California, one specimen (U. S. G.); upper San Pedro of Pacific Beach, San Diego (Arnold, under graciosana, s. s.; T. S. Oldroyd); "Saugus" of Ventura Co. (WaterfaU). The characters reUed upon by Martin to distinguish this variety from graciosana are probably of no real significance, though it may be possible to distinguish it by means of the characters described above as a variety of doubtful value. The width of the bands between the spiral grooves on the body whorl is very variable, being greatly dependent upon the state of preservation; and these bands are just as apt to be as wide in the typical variety as in mercedensis. The typical variety appears to be an unusual form or gerontic stage, occurring in beds of approximately the same age as those containing mercedensis; and the name graciosana may have been overlooked because of the poor original illustra- tion, whereas the more normal mercedensis has been reported from numerous localities. A few of the fossil specimens of mercedensis have as narrow spiral bands on the body whorl as does quentinensis (Dall), and it is not improbable that the latter is the same form still living. Moniliopsis quentinensis (Dall) Cryptogemma quentinensis Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 32, pi. 9, fig. 9, 1919. SheU much like that of M. graciosana variety mercedensis but younger, with the posterior notch more squarely on the periphery so that the axial riblets on the periphery' curve around it crescent shaped, and with the spiral cords on the lower part of the body whorl much narrower. Dimensions (from Dall) : Height of shell, 12 mm.; of last whorl, 9 mm.; diameter, 9 mm. Type specimen: No. 209,417 in the U. S. National Museum. Type locality: Off Cape San Quintin, Lower California, in 359 fathoms. Living: Ivnown only from the type locality. This form may or may not be distinct from graciosana. So little is known about it that its status cannot be determined, but it is worth while to point out that it is ap- proached by variations of graciosana variety mercedensis. M. quentinensis is in the trans- ition zone between Moniliopsis and Hemipleurotoma (the latter of which was formerly known under the name Cryptogemma, to which Dall assigned this species), and it is as- signed to Moniliopsis only because it is so closely related to graciosana. There are forms of Pleurotomoides that can be distinguished only by the position of the notch. Genus HEMIPLEUROTOMA Cossmann, 1889 Hemipleurotoma Cossmann, Ann. Soc. Roy. Malac. Belg., Vol. 24 (Ser. 4, Vol. 4), p. 260, 1889; Ess. Paleo. Comp., Vol. 2, p. 78, 1896. Coronia de Gregorio, Ann. Geol. Paleo., Vol. 7-8, 1890, type Pleurotoma acutiroslra Conrad, fide Cossmann. Cryptogemma Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 318, 1918, type (by original designation) Gemmula benthima Dall, Bull. Mus. Comp. Zool,, Harvard CoU., Vol. 43, p. 267, pi. 1, fig. 7, pi. 13, fig. 4, 1908, living from the Galapa- gos Islands to Ecuador in very deep water. Type (by original designation), Pleurotoma archimedis Bellardi, Mem. R. Accad. Sci. Torino, Ser. 2, Vol. 29, p. 30, pi. 1, fig. 18, 1878, middle Miocene of Italy. Bellardi's original figure is here reproduced, plate 26, figure 36. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 571 Shell of medium or small size, thin, high-spired ; whorls prominently angulated, the angulation coming at about the middle of the spire whorls, bemg surmounted by numerous small nodes as in Geinmula, and crossed by fine spiral threads, the rest of the sculpture consisting of distant spiral cords; aperture moderately elongate, posterior notch v-shaped, situated directly on the end of the angula- tion and bemg the cause of the beaded peripheral anal fascicle, inner lip resorbed, columella only slightly flexed, anterior canal moderately long, fairly narrow but not very clearly defined; operculum oval, with an apical nucleus. Geologic range: Lower Eocene to Recent (Cossmann). Distribution : Deep water of the Pacific, and probably also of the Atlantic. Hemipleurotoma is distinguished from Gemmula by its smaller, thinner, nearly always decorticated shell, and by its simple outer lip and shorter anterior canal. It is intermediate in character between Gemmula and Monilio-psis, and is distinguished by its Turris notch from Spirotropis and Pleurotomoides. Cossmann complicated the situation somewhat by citing Pleurotoma denticula Basterot as a neotype, but fortunately this species, unUke some of the others assigned by Cossmann to his genus, appears to be congeneric with the real type. Pleurotoma denticula Basterot is a Miocene species in Europe, but Heilprin reports it in the Eocene of Alabama. ^ Turris cingulifera (Lamarck), assigned by Cossmann to Hemipleurotoma, is probably a Turris in spite of its short anterior canal. Of the species assigned by Dall to Cryptogemma, the type appears to be the only one that belongs in this genus. The others should be distributed among the genera Spiro- tropis, Pleurotomoides, Taranis, Moniliopsis, etc. No species belong to Hemipleurotoma, as here outlined, that do not have the posterior notch on the peripheral keel. Moniliopsis quentinensis (Dall) is intermediate between Moniliopsis and Hemipleurotovia and might appropriately be classed here; but, as explained in the discussion of that species, its specific relationships tie it more closely to Moniliopsis. Dall intended to describe a species collected off the Hawaiian Islands in 284-290 fathoms by Dr. Heath as "Turris incilis" and also as " Pseudogemmula pailoloensis," according to specimens in the Oldroyd Col- lection at Stanford University; but apparently he never did so. The two are identical and belong to Hemipleurotoma. This form shows clearly that Hemipleurotoma is closely related to Turris. Genus TARANIS Jeffreys, 1870 Taranis Jeffreys, Ann. and Mag. Nat. Hist., Ser. 4, Vol. 5, p. 447, 1870. Type (by monotypy), Trophon morchi Malm, Goteborgs Kongliga Vetenskapsoch Vitterhet.s-Samhallet (Gothenburg), Handlingar, Ny Tidsfoljd, Vol. 8, p. 130, pi. 2, fig. 15, 1863, illustrated also by Sars, Moll. Reg. Arct. Norv., p. 220, pi. 17, fig. 8, 1878, also by Tryon, Man. Conch., Vol. 6, p. 315, pi. 29, fig. 66, 1884, and discussed by Harmer, Mon. Palffio. Soc, Vol. 68, Plio. Moll. Gt. Brit., Vol. 1, p. 301, 1915, though Harmer's figure is not typical; living on both sides of the Atlantic, from Norway to the Mediter- ranean and from Rhode Island to the Gulf of Mexico ; Pleistocene of England and possibly also of Italy. Shell small, spire elevated; whorls sculptured by a few prominent spiral ridges which are some- times arranged so that the whorls have an angulated appearance, these ridges crossed by more or less prominent lines or thin lamelUe of growth which slope backward from the top of the whorls to the most promment upper spiral, where they turn suddenly and begin sloping forward, giving the ' Proc. Acad. Nat. Sci.. Phila.. p. 214. pi. 13. fig. 10, 1879 = P. nodocarinaia Gabb? 572 San Diego Society of Natural History [ Memoirs spire whorls a zigzag pattern and indicating a shallow, v-shaped posterior notch on the outer lip some distance below the suture; aperture less than half the length of the shell, ovate, columella thin, curving to the left, anterior canal not clearly defined, rather short, not notched ; animal inoperculate. Geologic range: Upper Pliocene to Recent. Distribution: Reported from nearly everywhere in the northern hemisphere. This interesting little genus is clearly related to Hemipleurotoma ; and the more nearly smooth species incultus might be mistaken for a small Spirotropis. It is very unlikely that it has anything to do with Mangelia, with which it has usually been classed on account of being inoperculate. It is distinguished from Teres, perhaps artificially, by the position of the posterior notch. Taranis strongi (Arnold) Plate 26, Figure 37 Mangilia (Taranis) strongi Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 215, pi. 9, fig. 7, 1903. Taranis strongi Arnold, Dall, Bull. 112 U. S. Nat. Mus., p. 83, 1921 ; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 151, 1927. Shell large for the genus, spire high ; whorls sculptured by about seven spiral ridges, the largest on the angle marking the trace of the anal fasciole and the place where the growth Imes turn, one smaller above, close to the suture, and five below dimmishing m prominence, only tlie ujipermost of which shows on the spire whorls, gro\rth lines weak; ajDcrture short, ovate, columella short, turning to the left, anterior canal short, not defuaed, slightly recurved. Dimensions: Altitude, 12 mm. ; length of aperture, 5 mm. ; diameter of body whorl, 5. .5 mm. Type specimen: No. 162,549 in the U. S. National Museum. Type locality: Lower San Pedro Pleistocene of Deadman Island, San Pedro Harbor, Los Angeles Co., Calif. Pleistocene: "Pliocene" of Deadman Island and Santa Monica (Arnold); lower San Pedro series of San Pedro and Deadman Island (Arnold) ; upper San Pedro series (Palos Verdes) of Crawfish George's (Arnold). Living: Forrester Island, Alaska, to San Diego, California (Dall). This species is distinguished from morchi by its larger size, its relatively shorter aper- ture and columella, and its less prominent growth lines. It has, however, all the generic characters of morchi, and there is no question about its belonging to the genus Taranis. T. incultus is a closely related species or variety with weaker spiral sculpture. Taranis incultus (Moody) Borsonia inculta Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 54, pi. 1, figs. 2a, 26, 1916. Shell Like that of T. strongi, but with faint spiral sculpture. Dimensions: Altitude, 13.5 mm.; length of aperture, 6 mm.; diameter of body whorl, 6.9 mm. Type specimen: No. 11,081 at the University of California. Type locality: Fourth and Broadway, Los Angeles. Upper Pliocene: Type locality. This form may be a variety or even just a variation of strongi. It closely resembles a small typical Spirotropis. Genus TERES Bucquoy, Dautzenberg, and DoUfus, 1883 Teres Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, p. 86, 1883; Cossmann, Ess. Paleo. Comp., Vol. 2, p. 130, 1896. Teretia Norman, 1888, Teres emended; Monterosato, Nat. Sicil., An 9, p. 187, 1890; Dautzenberg and Fischer, R^s. Camp. Sci. Albert I, Prince de Monaco, Vol. 37, p. 50, 1912; Iredale, Proc. Zool. Soc. London, Vol. 13, p. 32, 1918. Volume I 1 PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 373 Tomopleura Casey, Trans. Acad. Sci. St. Louis, Vol. 14, p. 138, 1904, type (by original designation) Pleuroloma nivea Philippi, Zeitschr. f. Malak., p. 92, 18.51, operculum figured by Hedley, Rec. Australian Mus., Vol. 13, p. 218, pi. 42, fig. 4, 1922, living Formosa, and Karachi, India; Melvill, Proc. Malac. Soc. London, Vol. 12, p. 146, 1917. Melvill states that Pleuroloma liolacea Hinds, Zool. Voy. Sulphur, Moll., p. 16, pi. 5, fig. 8, 1844, Reeve, Conch. Icon., Vol. 1, Pleuroloma, pi. 22, species 186, 1845, Tryon, Man. Conch., Vol. 6, p. 169, pi. 4, fig. 12, pi. 3, figs. 29, 29«, 1884, not Pleuroloma violacea Mighels and C. B. Adams, 1842, is merely a color variety of nivea. Turridriipa Hedley, Rec. Australian Mus., Vol. 13, p. 226, 1922, type (by original designation) Pleuroloma aculigemmota Smith, Ann. and Mag. Nat. Hist., Ser. 4, Vol. 19, p. 489, 1877, synonymy by Hedley. loc. dt., and illustration, pi. 42, figs. 12, 13, 1922. Type (by original designation), Pleuroloma anceps Eichwald, Naturhist. von Lith. und Volh., p. 225, 1830, described and illustrated by B., D., and D., op. cit., p. 87, text figure 1, 1883, by Sars, Moll. Reg. Aret. Norv., p. 219, pi. 17, fig. 9, 1878, and by Tryon, Man. Conch., Vol. 6, p. 313, pi. 32, fig. 31, 1884 + Pleurotoma teres Forbes, 1844 (not "teres Forbes" in Reeve, January, 1844), living Norway to the Mediterranean. Shell small, spire moderately high ; whorls sculptured with revolvmg cords which sometimes show through on the interior and crenulate the outer lip, axial striations and growth lines much less promi- nent; aperture about two-fifths the length of the shell, outer lip curving back to a deep, roimded notch close to the suture, the notch leaving behmd it a broad, smooth fasciole, columella light, slightly flexuous, anterior canal iudistiiictly defined, short, not notched; animal (frequently ?) operculate. Geologic range: Miocene to Recent (B., D., and D.). Distribution: Practically world wide. This little genus is like Taranis except that the posterior notch is deep and close to the suture. It is clearly shown in the illustration of the type by Bucquoy, Dautzenberg, and Dollfus. The two little species described by Dall in 1919 as Taranis panope and Tar- anis zeuxippe from the equatorial region of the eastern Pacific probably belong here, and probably also most of Hedley's Filodrillia. Teres also bears some resemblance to Raphitoma, especially in Sars' figure of anceps and in niveus; but Raphitoma is larger, with stronger axial sculpture, and is said to be always inoperculate. Subgenus ASTHENOTOMA Harris and Burrows, 1891 Oligoloma Bellardi, Bull. Societa Malac. Ital. (Pisa), Vol. 1, p. 21, 1875; R. Accad. Sci., Torino, Memorie, Ser. 2, Vol. 29, p. 235, 1878; not Oligoloma Westwood, 1836; Dall, Proc. U. S. Nat. Mus., Vol. 54, pp. 329, 322, 1918. Aslhcnoloma Harris and Burrows, Eocene and Oligocene Beds of the Paris Basin, p. 113, 1891, new name for Oligoloma Bellardi; Cossmann, Ess. Pal^o. Comp., Vol. 2, p. 104, 1896; Hedley, Rec. Australian Mus., Vol. 13, p. 218, 1922; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 197, 1928. Type (by monotypy), Pleurotoma meneghinii Mayer = Pleurotoma tuberculata Fusch, fide Bellardi, 1878, p. 239, pi. 7, fig. 26, Miocene of Italy; originally described and figured by Pusct, in Polens Palaontologie, p. 143, pi. 12, fig. 2, (Stuttgart) 1837. The type of this genus or subgenus has generally been cited as Pleurotoma basteroti Desmoulins, 1842, Miocene of Europe, which may be the same as tuberculatus according to Dall, though Woodring does not think so. P. basteroti is a form like Teres with an obscure plication on the pillar. Many of the species assigned to Asthenotoma and Oligo- toma by Harmer and others might be better placed in Moniliopsis. It will be remembered that Moniliopsis belongs to the group of genera which has a tendency to develop colum- ellar plications, though typically it does not have one. Endiatoma Cossmann, 1896, is similar. 574 San Diego Society of Natural History [ Memoirs Genus CLAVUS Montfort, 1810 Claims Montfort, Conchyl. Syst., Vol. 2, p. 434, 1810; Tryon, Man. Conch., Vol. 6, pp. 155, 185, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 54, pp. 315, 324, 1918; Hedley, Rec. Australian Mus., Vol. 13, p. 254, 1922; Woodrins, Car- negie Inst. Wash., Publ. No. 385, p. 160, 1928. Clavicantha Swainson, Treat. Malac, pp. 155, 314, 1840, original list includes, impcnalis, spirnla, cnriica, echinala and auriculifera, all of Lamarck and all referred to figures in the Encyclopedia Methodique; Herrmannsen, Ind. Gen. Malac, Vol. 1, p. 246, 1846, type designated, Pleuroloma echinata Lamarck. Tylolia MelviU, Proc. Malac. Soc. London, Vol. 12, p. 160, 1917, type (by original designation) Strombus cmialicularis Bolten + Pleuroloma auriculifera Lamarck, Hist. Nat. Anim. s. Vert., Vol. 7, p. 91, 1822, illustrated by Reeve, Conch. Icon., Vol. 1, Pleuroloma, pi. 8, species 69, 1843, also, as Driliia auriculifera Lamarck, by Tryon, Man. Conch., Vol. 6, p. 185, pi. 8, fig. 25, 1884, -\-"Sirombus lividus Linnseus," Chemnitz, Neues Syst. Conch. Cab., Vol. 9, p. 193, pi. 136, figs. 1269, 1270, 1786, also noted by Gnielin in Linna-us, Syst. Nat., Ed. 13, p. 3525, 1791, and as "Driliia livida Linnseus" by Hedley, Proc. Linn. Soc. New South Wales, Vol. 34, p. 453, 1909, Recent, Philippine Islands. Type (by original designation), Claims flammulatus Montfort, described loc. cit., and figured pi. 109; + Clavatula echinata Lamarck, Ency. Meth. (Vers), Liste, p. 8, pi. 439, fig. 8, 1816; Pleuroloma echinata Lamarck, Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 5, Pleurotome, p. 45, pi. 20, figs. 2, 1839-40; Reeve, Conch. Icon., Vol. 1, Pleuroloma, pi. 6, species 48, 1843; Tryon, Man. Conch., Vol. 6, p. 185, pi. 9, fig. 31, 1884; = Strom- bus lividiis Linnaeus, Syst. Nat. Ed. 10, p. 746, 175S, fide Hedley, Rec. Australian Mus., Vol. 13, p. 255, 1922, cf. also Iredale, Proc. Malac. Soc. London, Vol. 12, p. 92, 1916; Recent, west coast of Africa. One of Kiener's figures is reproduced herewith, plate 26, figure 1. Shell of medium size, spire usually high, turreted; whorls sculptured on the angle with nodes or with more or less oblique ribs extendmg downward from the angle (m cases where there is no pro- noimced angle extendmg dowoiward from a point below th^ anal fasciole, which is free from them), spiral sculpture of variable strength, sometimes nearly obsolete, usually much finer on the anal fasciole, consistmg of spiral Imes or cords or grooves, growth lines usually evident; aperture a third or two-fifths the length of the shell, rarely approachmg a half, the mam part ovate, but each end prolonged mto a deep notched canal, outer lip thickened or thin according to whether the shell is at the rib-formuig growth stage or not, when thm sometimes crenulated by the spiral sculpture, but never denticulate within, outer lip often receding anteriorly at the base of the convex portion of the body whorl or even with a notch as in Strotnbus, posteriorly with a deep, rounded notch close to the suture but separated from the suture by a mound or ridge of light-colored material or callus which often extends in an arc aromid the upper end of the aperture and joms with the inner lip, which is usually heavily encrusted with smooth callus, columella usually short, straight, but in a few cases a little more elongate and slightly bent to the left, anterior canal usually mdistmcth^ defined by the incurvmg of the body whorl near the Stromboid notch but often so short that this feature is not notice- able, rather wide and deep, flaring a little at the very end, usually deeply notched behind, the notch causing a siphonal fasciole that the mner lip has difficult.y in covermg up; operculum thin, liorny, usuallj' with a termmal nucleus. Geologic range: Eocene to Recent (Cossmann, etc.). Distribution: Tropical and warm temperate waters of all oceans. The name Claims is antedated in the Turridce only by Turris Bolten and Clavatula Lamarck, both of which apply to different genera; and as Cossmann and others were wrong in supposing that the name was invalidated by Clava, and as it is inadmissible to use it as a subgenus of the later name Driliia, it is here applied to the most conspicuous genus of that branch of the Turridce that is characterized by a subsutural callus at the top of the inner lip, a deep posterior notch, a notched anterior canal, and a tall spire. This genus has recently been multiplied into many genera; but the present writers feel that after a few more distantly related groups are removed (Moniliopsis, Pseudojuelatoma, etc.), the remaining forms make such a well-defined unit that nothing is to be gained by Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 575 further complicating the generic nomenclature. A few subgenera are here recognized for convenience in classifying. Clams is undoubtedly closely related to Clavatula, as used here sensu lato to include not only the specialized typical Clavatulas that are grading over into Perrona but also the generalized, primitive type of the subgenus Knefastia. Claims is distinguished from Clavatula by its short, notched anterior canal, by the callus mound at the top of the inner lip, by the deeper posterior notch, the outer lip standing out a considerable distance prac- tically unsupported, by the lack of the sculptured band above the anal fasciole, and usually by its simpler sculpture. When Claims has spines as in C. canalicular is (Bolten), the spines are below the fasciole, whereas the spines that occur sometimes in Clavatula are above the fasciole. Clavus (Clathrodrillia) flavidulus (Lamarck) is closest to Knefastia, having sculpture in both directions and a somewhat longer canal; but it has the Clavus posterior notch and callus patch. Occasionally immature specimens and even a few adults may lack the Clavus patch, but they can usually be told by their other characters or by their specific relatives. Clavus is similarly distinguished from Turricula. The writers disagree with Dall, who, in 1918, referred Turricula maculosa (Sowerby) to Clavus; for that species has a longer anterior canal, not notched behind, and a shallower, unarmored posterior sinus. Clavus unimaculatus (Sowerby) is a typical Clavus approximating maculosa in appearance but showing all the distinguishing generic characters. Pseudonielatonia might sometimes be confused with Clavus in fossils that lack the last part of the body whorl ; but even the fossils can usually be distinguished by the band of nodes above the fasciole. When the lip is intact, P seudomelatoma is distinguished by the same characters as Clavatula. On the other hand, Clavus unquestionably grades into the smaller inoperculate Turrids, such as Mangelia and Clathurella. Clathurella is the closest, having the same general shape as Claims, with the same kind of aperture except that Clavus never has denticles on the outer lip ; and it would be surprising if the young of some of the many-whorled clathrate species, such as flavidulus were not described as new species of Clathurella. The subgenus Bela of Mangelia resembles the young of Clavus (Cymatosyrinx), but never has a sub- sutural callus. Bellaspira seems to be intermediate between Bela and Clavus {Drillia), having a small shell and a nearly obsolete sinus as in Bela, but a thick shell, a small callus patch at the top of the outer lip, and an operculum as in Drillia. Subgenus CLAVUS, s. s. Shell with nearly obsolete sculpture except for a row of sharp, rounded nodes or hollow spines on the angle. This subgenus includes lividus (Linnseus) from west Africa, canalicularis (Bolten) from the Philippines, and unimaculatus (Sowerby), ranging from Panama to the Gulf of California. A Gulf of California specimen of the last-named species is figured herewith, plate 26, figures 2a, 2b. Subgenus CYMATOSYRINX Dall, 1889 Cymatosyrinx Dall, Bull. Mus, Comp. ZooL, Vol. 18, p. 9.5, 1889; Cossmann, Ess. Pal6o. Comp., Vol. 2, p. 86, 1896; Thiele, Wiss. Erg. Deutsch. Tiefsee-E.xped., Vol. 17, p. 203, 1925. Elseocyma Dall, Proe. U. S. Nat. Mus., Vol. 54, p. 317, 1918, type (by original designation) Drillia empyrosia Dall (see C paHidus below). Type (by original designation), Pleurotoma lunatum Lea, Trans. Amer. Phil. Soc, New Series, Vol. 9, p. 269, pi. 37, fig. 93, 1846, illustration reproduced herewith, plate 576 San Diego Society of Natural History [ Memoirs 26, figure 7; Tertiary of Petersburg, Virginia, said by Dall to be Miocene, range given as Miocene to Pliocene (Dall). Shell like that of the t^-pical subgenus but with the nodes on the angle extended downwards as long, curving costiE, fine spiral grooves sometimes evident in the interspaces. Geologic range: Miocene to Recent. Distribution: California and Florida to Panama, probably elsewhere. This subgenus is so close to the typical subgenus that it might better be considered a section or a synonym, as Cossmann considered it. There is no reason whatever for sep- arating Elceocyma. Some of the smaller species like C. hemphiUi (Stearns) might be sectionally separable, but for the present the writers think it better not to make any more subdivisions. Clavus (Cymatosyrinx) pallidus (Sowerby) Plate 26, Figures 16o, 16b, 17 Pleurotoma pallida Sowerby, Proc. Zool. Soc. London, p. 137, 183.3; Miill., Sj'nop. Xov. Test. Viv., p. 113, 1836; Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 16, fig. 134, 1843; .\dams. Cat. Sh. Panama, p. 146, 1852. DriUia pallida Sowerby, Tryon, Man. Conch., Vol. 6, p. 196, pi. 14, fig. 8, 1884. Drillia empyrosia Dall, NautUus, Vol. 12, p. 127, 1889; Proc. U. S. Nat. Mus., Vol. 24, p. 516, pi. 39, fig. 5, 1902. Drillia johnsoni Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 206, pi. 8, fig. 17, 1903; Smithsonian Misc. Coll., Vol. 50, Pt. 4, pi. 54, fig. 13, 1907; Arnold and Anderson, BuU. 322 U. S. Geol. Survey, pi. 21, fig. 13, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914. Drillia waldorfensis Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 13, pi. 54, fig. 12, 1907; Arnold and Anderson, Bull. 322 U. S. Geol. Survey, pi. 21, fig. 12, 1907. Els;ocyma empyrosia Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 12, pi. 4, fig. 1, 1919. Elxocyma sgina Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 12, pi. 4, fig. 2, 1919. Elxocyma halocydne Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 11, pi. 4, fig. 4, 1919. Elseocyma ianihe Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 9, pi. 4, fig. 6, 1919. Cymatosyrinx hecuba Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 9, pi. 20, fig. 9, 1919. Clathrodrillia paziana Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 14, pi. 5, fig. 1, 1919. Cymatosyrinx [Elxoajma) johnsoni Arnold, Dall, Bull. 112 U. S. Nat. Mus., p. 69, 1921. Cymatosyrinx {Ela!ocyma) empyrosia Dall, Bull. 112 U. S. Nat. Mus., p. 69, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 68, Pt. 3, pi. 100, fig. 5, 1927. Cymatosyrinx (Els-ocyma) halocydne Dall, Bull. 112 U. S. Nat. Mus., p. 69, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, pi. 19, fig. 5, 1927. Shell of large or medium size, spire high; whorls of moderate convexity below the concave anal fascicle, sculptured with 10 to 15 rather low, sharp (except where worn rounded), distant, axial ribs which are barely distmguishable from the strongly curving growth lines on the anal fasciole, but ap- pear quite strong on the side of the whorl, where they descend more or less oljliquely, growing faint on the base of the body whorl, and curving around again past the vertical, ribs on the early whorls fewer and less noticeably oblique, but on the body whorl and sometimes on the penultimate whorl becoming irregular and much more oblique, either changing into fewer coarse waves, or, if the waves die out, breaking up into many irregular riblets hardly distinguishable from the growth lines, spiral sculpture of sharp grooves with flat-topped interspaces, usually worn off the ribs; aperture varying from a third to two-fifths the length of the shell, the columella and anterior canal sometimes some- what elongated, especially in young specimens, but otherwise typical of Cijmatosijrinx, the strong labial calluses not developing fully until the shell reaches the adult stage. Dimensions of large specimen with short aperture: Altitude, 41 mm.; length of aperture, 13 mm. ; diameter of body whorl, 13 mm. ; of Pliocene specimen, here figured: altitude, 22 mm. (allowing 1 nun. for broken apex) ; length of aperture, 8 mm. ; diameter of body whorl, 8 mm. Tijpe specimens: Of pallidus, in the British Museum (?) ; of empyrosia, in the Oldroyd Collection at Stanford University; of all the others, in the U. S. National Museum, johnsoni No. 162,537, ivaldorfensis No. 165,270, o'gina No. 266,371, halocydne No. 216,748, ianthe No. 212,367, hecuba No. 73,995, and pazianus No. 311,372. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 577 Type localities: Of pallidus, Panama; of empyrosia and halocydne, in deep water off San Pedro, Calif.; o^ johnsoni, upper San Pedro Pleistocene of San Pedro; of waldorfensis, Pliocene of the Waldorf asphalt mine, Santa Barbara Co. ; of oegina, ianthe, and hecuba, Gulf of California; of pazianus, La Paz, Lower California. M. Pliocene: Type locality of waldorfensis; Holser Canyon, Los Angeles Co., north of the Santa Clara \'alley (English); S. D. S. N. H. loc. 2I7b, Holser Canyon, six specimens (H. R. G.). Pleistocene: Type locality o{ johnsoni; Timber Canyon, Ventura Co. (collection at Stanford University). Liting: Santa Barbara to Panama. The reader will probably be surprised by the synonymy given above, and it may be of help to note the different degrees of assurance with which the names are synonymized. C. pallidus is unknown to the writers except in Reeve's figure and the original description, which indicate a shell exactly like empyrosia except that it is said to be light colored and the basal extremity of the columella is somewhat twisted to the left. As one specimen of empyrosia in the Oldroyd Collection at Stanford LTniversity is light colored, the color difference is probably not of significance; but it is barely possible that the twist of the col- umella might be an indication that the forms are different species. The synonymy of johnsoni with empyrosia is certain. The form waldorfensis, although it appears to have a narrower shell, was described from a locality at which johnsoni occurs, and actual mea- surements show that its shell is not appreciably narrower than that of small specimens of johnsoni. Living specimens show that the form of the costae on empyrosia varies, that cegina is merely an individual variation with the costse stronger and somewhat node-like at the top, and that hecuba is but a worn specimen. The form halocydne is an extreme with more numerous costse, the costae being extremely oblique, low, and irregular on the last two whorls, and the anterior canal is slightly longer. This form might be separable as a variety ; but the condition of the ribs on the last whorl appears to be merely a gerontic character, and the length of the canal an individual or growth-stage variation. The form ianthe, which is a pazianus with a mature aperture, might also be distinguished as a variety with longer anterior canal, more convex whorls, stronger spiral grooves, and smaller size. The specimens from Holser Canyon are like this last form, though somewhat larger. In some cases weathering has hollowed out the anal fasciole on these specimens leaving a Pseudo7nelatoma-like band above. C. cerope (Dall),^ from the Gulf of California, looks very much like a young empyrosia or pallidtis (though its aperture shows it to be mature), and it may really be just another variety or synonym. C. alcyone (Dall)'-, also from the Gulf of California, which was named the type of the section Kylix,^ may be a related species with the apertural callus not yet developed, resembling somewhat the form pazianus. Clavus (Cyniatos3rriiix) hemphilli (Stearns) Plate 26, Figure 8 Plevroioma {Drillia) hemphilli Stearns, Conchological Memoranda, No. 7, p. 2, separately printed, Journal & Argus Print, Petaluma, Calif., August 28, 1871; Proc. Calif. Acad. Sci., Vol. 5, p. 80, pi. 1, fig. 3, 1873. Drillia hemphilli Stearns, Tryon, Man. Conch., Vol. 6, p. 185, pi. 13, fig. 49, 1884; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 204, pi. 5, fig. 8, 1903. Clalhurella plicatella Dall, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 289, 1908. Cymatosyrinx plicatella Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 7, pi. 20, fig. 4, 1919. ■ Elxocyma aerope Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 13, pi. 1, fig. 3, 1919. » Clathrodrillia? (Kylix) alcyone Dall, Proc. U. S. Nat. Mus., Vol. 56. p. 20, pi. 2, fig. 3, 1919. Mangiliaf hermione Dall, Proc. U. S. Nat. Mus.. Vol. 56, p. 70, pi. 19, fig. 6, 1919 (young). ?Clathrudrilliaf (Kylix) alcmene Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 19, 1919. ' Kylix Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 327, 1918, nomen nudum until 1919. 578 San Diego Society of Natural History [Memoirs Cymatosyrinx ? ferminiana Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 7, pi. 8, fig. 4, 1919. Cymatosyrinx f palmcri Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 8, pi. 19, fig. 7, 1919. Elseocyma atlalia Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 10, pi. 18, fig. 7, 1919. Elxocyma arbela Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 10, pi. 4, fig. 3, 1919; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Elxocyma xolia Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 11, pi. 3, fig. 1, 1919. Cymatosyrinx {Elxocyma) hemphilli Stearns, Dall, Bull. 112 U. S. Nat. Mus., p. 69, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 69, 1927. Elxocyma hemphilli Stearns, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Shell small, rather high spired; whorls moderately rounded, sculptured with 10-14 usually dis- tract, distant, somewhat oblique axial riblets, the riblets often becoming obsolete or indistinct on the body whorl, and occasionally on one or more of the spire whorls, riblets broken posteriorly by the anal fasciole, which separates off a Pseudmnelatom.a-like nodulous band just below the suture, the band being much more conspicuous at some times than at others, spiral sculpture of a few fine, sharp, distant grooves showmg only in the mterspaces between the riblets and on the columella, or not at all, sometimes fairly conspicuous on specimens with obsolete riblets; aperture about a third the length of the shell, ovate, notched at both ends, the posterior notch bemg deep and narrower and close to the suture, the anterior comparatively broad and shallow, the top of the mner lip with a moimd of callus bordering the notch, columella short, anterior canal sometimes defined, short. Dimensions: Altitude, 12 mm.; length of aperture, 4 mm.; chameter of body whorl, 4 mm. Type specimens: All (except perhaps that of hemphilli) in the U. S. National Museum, plicatellus No. 110, QOA, ferminianus No. 214,267, palmeri No. 56,036, attalia No. 168,677, arbela No. 106,495, aolia No. 208,592. Type localities: Of hemphilli, Todos Santos Bay, Lower California; of plicatellus, Panama Bay; oiferminianus, Point San Fermin, Lower California; of palmeri, head of the Gulf of California; of attalia, west coast of Mexico, probably near Mazatlan; of arbela, Scammons Lagoon, Lower California; of ceolia. Cape Tepoca, Gulf of California. Pleistocene: Lower San Pedro series of Deadman Island and San Pedro, Los Angeles Co. (Arnold) ; Barlow Canyon, Ventura Co. (Arnold); 26th St. and Spanish Bight, San Diego (Arnold); San Quintin Bay, Lower California (Jordan); loc. 249 S. D. S. N. H. north of Ventura, two specimens (U. S. G.); upper San Pedro series of Los Cerritos ( = Signal Hill), San Pedro, and Crawfish George's (Arnold); upper San Pedro of the palisades north of Santa Monica (F. C. Clark). lAving: Santa Barbara, California, to Panama. This species, like pallidus, is variable in form and has received many names. The most striking variation is that named attalia, which has a tall, narrow spire and feeble ribs. Specimens of this variation are labeled hemphilli in the Oldroyd Collection at Stanford University. The type figure of hemphilli shows a shell with only moderately high spire, the ribs becoming obsolete on the last whorl. Other variations have strong, sharp ribs even on the body whorl, more or less proininent spiral sculpture and a sutural band, etc., or different combinations of these characters. The sutural band recalls Pseudomelatoma, but the subsutural callus on the inner lip shows that the species belongs to Clavus. C. hemphilli is smaller, with finer sculpture than pallidus. It is difficultly distinguished from C. elissa, which has a shorter, more ovate shape, low broad riblets, and practically no spiral sculpture, C. elissa being perhaps but a variety of hemphilli. C. albicostatus (Sowerby),! from the Galapagos Islands, is very similar and may be the earliest name for this species. It is somewhat larger and appears to lack the posterior band. Clavus (Cymatosyrinx) eUssa (Dall) Cymatosyrinx elissa Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 6, pi. 20, fig. 1, 1919. Cymatosyrinx hespera Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 6, pi. 20, fig. 2, 1919. Cymatosynnx f lalage Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 7, pi. 20, fig. 3, 1919. ? Cymatosyrinx idothea Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 8, pi. 21, fig. 11, 1919. > Pleurotoma albicostata Sowerby, Proc. Zool. Soc. London, p. 135, 1833; Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 8, fig. 62, 1843. DriUia albicostata Sowerby. Tryon. Man. Conch,. Vol. 6, p. 205, pi. 13, fig. 57. 1884. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 579 Shell much like that of hempMlli, but with a shorter spire, giving it a more ovate outline, with low, faint axial ribs and practically no spiral sculpture. Dimensions: Altitude, 9 mm.; length of aperture, 3 nun.; diameter of body whorl, 3.5 mm. Type specimens: In the U. S. National Museum, elissa No. 122,799a, hespera No. 122,799, lalage No. 55,491, idothea No. 96,194. Type localities: Of elissa and hespera, Panama Bay; of lalage, Gulf of California; of idothea. Straits of Magellan, South America. lAving: Gulf of California to the Straits of Magellan. Objectively considered, there is little to separate the named forms listed in the synonymy. The Patagonian form might be distinguishable by its more oblique ribs, but if the variability of this character is as great in this species as in pallidus and hemphilli, it will not serve to separate it. Subgenus CLATHRODRILLIA Dall, 1918 ClathrodrilUa Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 317, 1918. Type (by original designation), "Pleurotoma gibbosa Reeve," Conch. Icon., Vol. 1, Pleurotoma, pi. 5, species 30, 1843; = Murex gibbosus von Born, Index Rerum Naturalium Musei Csesarei Vindobonensis, p. 325, 1778; Testacea Mus. Caes Vind., p. 321, pi. 11, figs. 12, 13, 1780, these figures reproduced here, plate 26, figures 3a, 3fe; also illustrated by Chemnitz, Neues Syst. Conch. Cab., Vol. 11, p. 112, pi. 190, figs. 1833, 1834, not figs. 1829, 1830 (= flavidulus Lamarck var.), 1795; Kiener, Spec. Gen. et Icon. Coq. Viv., Vol. 5, Pleurotome, p. 35, pi. 16, fig. 2, 1839-40; Tryon, Man. Conch., Vol. 6, p. 179, pi. 9, fig. 54, 1884. Chemnitz says it comes from the Red Sea, a variety of the form which La- marck later called flavidulus, Red Sea to Japan; but Tryon says it is from the West Indies, which is probably correct. Reeve and von Born did not give the locality. Shell like that of the typical subgenus but sculptured with axial ribs instead of nodes and with prominent spiral cords overriding the ribs. Geologic range : Pliocene to Recent (California) . Distribution: Warm and tropical oceans. The close relation between this subgenus and the typical is illustrated by Reeve's remark that C. unimaculatus (Sowerby), a member of the typical subgenus, "may probably be merely a white variety of PL gibbosa." The intergradation with Cymatosyrinx is even more intimate, the separation being made merely on the strength of the spiral sculpture. Indeed, the distinctions between these three subgenera are so artificial that it would not be unreasonable to reduce them to the rank of sections or to abandon them entirely. The subgenus Drillia is shorter and smaller, with a few large, rounded axial ribs. The sub- genus Crassispira has a sculptured band above the anal fasciole showing the relationship with Claratula, and the sculpture usually has a more granular texture. Some species of ClathrodrilUa, like flavidulus (Lamarck) (see plate 26, figures 4a, 46), have a longer ante- rior canal and simulate Clavatula or Turricula, but the armored posterior notch shows that they belong to this group. Ball's C. (ClathrodrilUa) panthea^ is an illustration of this form. It is evident that the genera Clavatula, Turricula, and Clavus and the corresponding branches of the Turridce intergrade at this point. ' Turricula {Surcula) panthca Dall. Proc. I'. S. Nat. Mus., Vol. 56, p. 4. pi. 1. fig. 5, 1910. 580 San Diego Society of Natural History [ Memoirs Clavus (Clathrodrillia) coalingensis (Arnold) Plate 26, Figures 14a, 146, 15 Pleurotoma cnalingensis Arnold, Bull. 396 U. S. Geol. Survey, p. 90, pi. 22, fig. 2, Jan. 15, 1910, figure reprinted in Bull. 398, pi. 44, fig. 2, 1910. Turris elsmerensis English, Univ. Calif. Publ. Geol., Vol. 8, p. 216, pi. 23, figs. 4a, 46, 1914. Tunis (Balhytoma) coalingensis Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 203, 1916. Turris coalingensis (Arnold), Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 213, 221, 1917. Shell of medium size, spire moderately high; whorls with a rounded shoulder, scul]itured with about ten rounded axial ribs extending from the shoulder downiward and dymg out on the lower part of the body whorl, spiral sculpture of three or four spiral grooves on the anal fasciole above the shoulder, on the rest of the whorl of spiral cords, two to four showing on the spire whorls, about fif- teen on the body whorl, with a number of minor intercalaries, especially on the upper part of the whorls, sometimes very mconspicuous, sometimes almost as strong as the primary cords and making the spiral sculpture appear finer; aperture aljout two-fifths the length of the shell, lenticular, posterior notch deep and romided, close to the suture, columella nearly smooth, with the posterior callus patch, if present, very inconspicuous, anterior canal poorly defined, moderately notched. Dimensions : Altitude, 27 mm. ; length of aperture, 12 mm. ; diameter of body whorl, 1 1 mm. Type specimens: Of coalingensis, No. 165,509 in the U. S. National Museum; of elsmerensis, in the collection of the University of California. Type localities: Of coalingensis, basal portion of the Etchegoin formation, middle Pliocene, of the Coalinga district, middle California; of elsmerensis, lower Pliocene of Elsmere Canyon, Los Angeles County. Lower Pliocene: Elsmere Canyon (English); Coalinga district (Nomland); localities 204 and 207, S. D. S. N. H., Elsmere Canyon, one specimen each (H. R. G.). Middle Pliocene: Coalinga district (Arnold; Nomland). It takes but a few specimens to illustrate the variation of this species and show that elsmerensis is the same as coalingensis. The nearest living form is C. panthea (Dall) from Panama, mentioned above, which is somewhat larger but may in time be found to be conspecific. The whole range of this species is much more significant than the isolated occurrences of several supposedly different forms. Although the callus patch at the top of the inner lip is not clearly shown on any fossil specimen seen by the writers, there can be little question about its specific relationships and its assignment to this group. Clathrodrillia callianira Dall, 1919, from Lower California, also belongs to this group, but it has a relatively higher, narrower spire. Subgenus CRASSISPIRA Swainson, 1840 Crassisjrira Swainson, Treat. Malac, pp. 152, 313, 1840, species included, Pleurotoma bottx Auct. and C.fasciata Swain- son, fig. 17d, p. 151; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 318, March, 1847, type cited Pleurotoma bottx Valenciennes; Cossmann, Ess. Pal4o Comp., Vol. 2, p. 85, 1896; Dall, Proc. U. S. Nat. Mus., Vol. 54, pp. 317, 324, 1918; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 147, 1928. Type (by subsequent designation, Herrmannsen, 1847), Pleurotoma botlce Valen- ciennes in Kiener, Spec. Gen. et Icon. Coq. Viv., Vol. 5, Pleurotome, p. 33, pi. 15, figs. 2, 1839-40, these figures reproduced herewith, plate 26, figures 6a, 6fe; living, Mazatlan, west coast of Mexico. Shell like that of the typical subgenus but with a relatively longer aperture, with a smooth or sculptured band above the posterior notch and long axial costse extending from the anal fasciole down- ward. Geologic range: Eocene ?; Miocene to Recent; in California, Pliocene to Recent. Distribution: Warm and tropical oceans. The writers do not believe that there is any need for doubt concerning the type desig- nation of this subgenus. The name Pleurotoma bottce had evidently been circulating Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 581 among conchologists a number of years before Kiener published it and credited it to Valenciennes; and as Kiener's work appeared at approximately the same time that Swain- son's did, it is not unlikely that Swainson had not yet seen the pub'ished name. In any case Swainson apparently meant Pleurotonia hottw as then generally understood by con- chologists; and since Valenciennes in Kiener has full title to being an author, there is nothing to imply that Pleurotonia hottce Valenciennes in Kiener was excluded from Pleurotoma hottce Auctorum. Surely the name had not been published long enough to have been frequently misidentified and to cause Swainson to try to indicate the mis- identification in the crude manner too frequently employed by later workers. Even in case hottce were not accepted, Swainson's other species is almost surely a Turrid of this same group, the fact that Swainson considered it intermediate between the Pyrenidce and the Turridce not being significant. There is some difficulty about the identification of Pleurotoma hottce, which Reeve and Tryon considered the same as incrassatus (Sowerby), though the latter appears quite differ- ent. However, continued collecting along the coast of Mazatlan ought to yield some specimens and determine the specific identity of the name, and in the meantime it is clear enough to what group the species belongs. Woodring has figured a number of species illustrating the group, though none of them is as large as the type, which is two inches long. Crassispira is difficult to distinguish from Clathrodrillia, for both have the Clavus generic characters and sculpture in both directions; but Crassispira does not have shouldered whorls and the suture is higher on the preceding whorl, somewhat as in Clavatula, with one or more spiral ridges and sometimes a band of nodular sculpture above the anal fasciole. The anterior canal is short and undefined. Crassopleura Monterosato may be a synonym.' Clavus (Crassispira) montereyensis (Stearns) Plate 26, Figure 9 Pleurotoma (Drillia) montereyensis Stearns, Conchological Memoranda, No. 7, p. 2, separately printed, Journal and Argus Press, Petaluma, Calif., August 28, 1871; Proc. Calif. Acad. Sci., Vol. 5, p. 80, pi. 1, fig. 2, 1873. Drillia montereyensis Stearns, Tryon, Man. Conch., Vol. 6, p. 184, pi. 12, fig. 30, 1884; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 207, 1903. Crassispira arsinoe Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 26, pi. 6, fig. 4, 1919. Crassispira montereyensis Stearns, Dall, Bull. 112 U. S. Nat. Mus., p. 70, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 77, 1927. Shell small, thick, spire moderately high; whorls not much inflated, sculptured with about thirteen low, indistinct axial riblets, riblets nodose below the anal fasciole and dying out dowiiward, absent on the fasciole, and sometimes appearing as nodes on the band above the fasciole, spiral sculpture of indistinct cords making the riblets below the fasciole granular, anal fasciole smooth except for curving gro\\-th lines; aperture about a third the length of the shell, posterior notch some distance l^elow the suture, deep, rounded, the space above it within the aperture filled with callus, inner lip encrusted, columella straight, not defined from the regularly curving outline of the body whorl, anterior canal not defined, short, broad, notched behind. Dimensions: Altitude, 16 mm.; length of aperture, 6 mm.; diameter of body whorl, 6 mm. Type specimens: Of montereyensis, in the U. S. National Museum {fide Oldroyd); of arsinoe. No. 56,135 in the U. S. National Museum. Type localities: Of montereyensis, Monterey, Calif., of arsinoe, Bartolome Bay, Lower California. 1 Crassopleura Monterosato, Nomen. Gen. Spec. Medit., p. 127, 1SS4, type (by monotypy) Pleurotoma maraxignx Bivona, 1838, + Pleuro- toma incisa Reeve, 1843. 582 San Diego Society of Natural History [Memoirs Pleistocene: Lower San Pedro series of San Pedro, Los Angeles Co., Calif. (Arnold). Living: Monterey to Mazatlan, Mexico (Dall). This species is distinguished by its sculpture and by the uninflected curve at the base of the body whorl. It usually has a strong callus at the top of the inner lip, but otherwise the posterior notch is like that of Clavatula. Specimens with more numerous riblets and more prominently sculptured sutural band are usually assigned to the typical variety. Clavus (Crassispira) montereyensis (Stearns) variety amathea (Dall) "Drillia piidica Hinds," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 208, pi. 8, fig. 13, 1903. Crassispira amathea Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 27, pi. 6, fig. 2, 1919. Crassispira eurynome Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 21, pi. 7, fig. 5, 1919 (young). Shell like that of the typical variety but with fewer ribs, narrower spire, and less prominent sutural band. Type specimens: In the U. S. National Museum, amathea No. 56,099, eurynome No. 59,345. Type locality: Of both names, Acapulco, Mexico. Pleistocene: Upper San Pedro series of San Pedro (Arnold). Living: Acapulco, etc. Specimens are usually assigned to this variety when worn. The range and distribu- tion are within those of the typical variety. C. pudicus (Hinds), of which C. impressus (Hinds) is probably a synonym, belongs to the subgenus Cymatosyrinx. It is living in Panama. Clavus (Crassispira) sp. Plate 26, Figure 10 A fragmentary specimen belonging to the subgenus Crassispira, larger than monterey- ensis and with finer sculpture, but not sufficiently well preserved to describe as a new species, was found at loc. 217b S. D. S. N. H. in the middle Pliocene of Holser Canyon, Los Angeles Co. It is somewhat like rugitectus (Dall),' which in turn is somewhat like hottce and incrassatus (Sowerby), 1834, (not preoccupied by Dujardin, 1837). It has the sculpture and shape of Moniliopsis grippi Dall, but its incrusted inner lip with the callus patch at the top shows that it belongs to Clavus. Dimensions: Altitude (apex defective), 20 mm.; length of aperture, 9 mm.; diameter of body whorl, 9 mm. Other species referable to the subgenus Crassispira are : "Clathrodrillia (Moniliopsis)" fryei Weaver and Palmer, 1922, Eocene of Washington. Crassispira tepocana Dall, 1919, — like hotta?. "Clathrodrillia" castianira Dall, 1919, — young of tepocanus ? Crassispira f martinensis Dall, 1919, — similar to montereyensis. Crassispira nephele Dall, 1919, — ditto. Crassispira candace Dall, 1919, — ditto. Crassispira bacchia Dall, 1919, — more carinate. Crassispira dirce Dall, 1919, — still more carinate. "Drillia" appressa Carpenter, 1864, figured by Dall, 1919. The species referred by Dall to the section Carinodrillia, with the exception of the type, together with the species referred to it by Woodring, probably belong in the sub- genus Clathrodrillia rather than here. The type of Carinodrillia appears to belong with Suavodrillia in Clavatula, sensu lata, and is probably related to the subgenus Knefastia. ' Turris {Crassispira) rugitecta Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 226. 1918. Crassispira t rugitecta Dall. Proc. U. S. Nat. Mus., Vol. 56, p. 26, pi. 7. fig, 0. WIS. VoLOTns I ] Pliocene and Pleistocene Mollusca of California 583 Subgenus BRACHYTOMA Swainson, 1840 Brachytoma Swainson, Treat. Malac, pp. 154, 314, 1840, original list consisting of the two species: (1) Pleurotoma strombiformis G. B. Sowerby, Conch. Man., fig. 381, 1839 [= Pleurotoma slromhoides J. Sowerby, Gen. Sh., Pleurotoma, fig. 4, 1820-25, also figured by Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 9, species 71, 1843, and by Tryon, Man. Conch., Vol. 6, p. 176, pi. 10, fig. 58, 1884], and (2) Brachytoma castanea Swainson, Chemnitz, figs. 1831, 1482 [Chemnitz, Conchyl. Cab., Vol. 11, p. 114, pi. 190, figs. 1831, 1832, 1795, is Murex {Turris) coronata Chemnitz, the tj^je of Clavatula; "fig. 1482" is probably a misprint for 1832, for Vol. 10, p. 208, pi. 155, fig. 1482, 1788, is a Strombus sp.]; type designated by Herrmannsen, Ind. Gen. Malac, Vol. 1, p. 121, 1846, and by Gray, Proc. Zool. Soc. London, p. 134, 1847, Pleurotoma strombiformis Sowerby; name mis- spelled by the younger Sowerby Brachitoma (fide Hermannsen), and by Gray and Tryon Brachystoma. Type (by subsequent designation, Herrmannsen, 1846), Pleurotoma strombiformis Sowerby, Recent, Bay of Panama (for references see above). Shell like that of the typical subgenus, but -svith a relatively short spire and an elongate aperture, the nodes on the shoulders of the whorls drawn out into short axial costae. The type of this subgenus is peculiar because of its elongate aperture and anterior canal, and in this respect resembles Clavatula; but in all other characters it is clearly a Clavus. Other species grade into Crassispira, but they have more shouldered whorls and lack the sculpture on the anal fasciole. Cymatosyrinx has a higher spire and a shorter aperture. Clavus (Brachytoma 7) nigerrimus (Sowerby) Pleurotoma nigerrima Sowerby, Proc. Zool. Soc. London for 1833, p. 137, April, 1834; Reeve, Conch. Icon., \o\. 1, Pleurotoma, pi. 12, fig. 102, 1843. Drillia nigerrima Sowerby, Tryon, Man. Conch., Vol. 6, p. 196 (not the synonymy), pi. 14, fig. 91, 1884; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 208, 1909. Crassispira nigerrima Sowerby, Dall, Nautilus, Vol. 32, p. 23, 1918. Crassispira erigone Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 21, pi. 7, fig. 8, 1919. f Elxocyma abdera DaU, Proc. U. S. Nat. Mus., Vol. 56, p. 12, pi. 4, fig. 5, 1919. Shell of medium size, spire short, tapering; whorls with a strong, rounded shoulder, the area above concave, unsculptured, that below convex, sculptured by about twelve narrow, distant axial riblets, which are most prominent on the shoulder, where they are sometimes nodose, and die out downward, spiral sculpture of indistinct lines in the interspaces between the ribs, with a few distant, stronger spiral cords on the lower part of the body whorl which pass over and nodulate the ribs; aperture about two-fifths the length of the shell, ovate-elongate, with a strongly armored posterior notch, a moderately long, straight columella, and a short, poorly defined anterior canal. Dimensions : Altitude, 21 mm.; length of aperture, 9 mm.; diameter of body whorl, 8.5 mm. Type specimens: Of nigerrimus, in the British Museum (?) ; of erigone, No. 212,368, of abdera, No. 212,373, in the U. S. National Museum. Type locality: Of all three names, Panama. Pleistocene: Magdalena Bay, Lower California (Dall, 1918). hiving: Gulf of California to Ecuador (Dall, 1909). This species is somewhat intermediate between Brachytoma and Crassispira. The type of the former is distinguished by its unusually elongate anterior canal. C. (Crassi- spira) tepocanus (Dall) is distinguished by its more numerous ribs, its weaker shoulder, and the spiral sculpture on the anal fasciole. Subgenus DRILLIA Gray, 1838 Drillia Gray, Ami. and Mag. Nat. Hist., Vol. 1, p. 28, 1838, only four species included, umhilicaln Gray, clathrata Gray, bicolor Gray, suturalis Gray; Proc. Zool. Soc. London, p. 134, 1847, type not cited; Cossmann, Ann. Soc. Roy. Malac. Belgique, Vol. 24 (Ser. 4, Vol. 4), p. 273, 1889, type cited Drillia iimbiUcala Gray; Ess. Paleo. Comp., Vol. 2, p. 82, 1896; Dall, Proc. U. S. Nat. Mus., Vol. 54, pp. 317, .325, 1918; Thiele, Wiss. Erg. Deutsch. Tiefsee-Exped., Vol. 17, p. 203, 1925; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 148, 1928. 584 San Diego Society of Natural History [ Memoirs Type (by subsequent designation, Cossmann, 1889), Drillia umbilicata Gray, de- scribed by Gray, 1838, illustrated by Reeve, Conch. Icon., Vol. 1, Pleurotoina, pi. 11, fig. 97, 1843, and by Tryon, Man. Conch., Vol. 6, p. 179, pi. 11, fig. 82, pi. 30, fig. 78, 1884. Shell like that of the typical subgenus but smaller, with only a few, short, very coarse axial riblets extending downward below the anal f asciole, riblets crossed by fine spiral lines ; anal fascicle concave. Distribution: Tropical Atlantic. C. hexagonus (Sowerby), illustrated by Reeve and Tryon, from Central America, ap- pears to belong to this subgenus also. This group is a peculiar specialized derivative of the more normal forms of the genus; but until it was discovered that Clavus was an earlier name for the genus, all of the forms were appropriately assigned to Drillia, the oldest name for the genus as then known. Now only the type and perhaps a few others belong to Drillia, and apparently none of them is represented in the California region. Drillia is related to Bellaspira, which might also be considered a subgenus of Clavus. Thiele found that umbilicatus (Gray) has a radula like that of Spirotropis, with which he classes it accordingly. He also thinksthat Clavus and Cymatosyrinxhave a similar radula, but that the radula of Crassispira is different and that therefore this group is unrelated. The writers believe that the Spirotropis-Drillia radula, having all the rows of teeth rep- resented, is the primitive type for the family, that its presence in various branches of the family does not necessarily indicate any closer relationship, and that on the other hand, groups of greater or smaller size in various branches of the family, such as Crassispira, have lost independently, perhaps recently, part of their teeth. Genus BELLASPIRA Conrad, 1867 Bellaspira Conrad, Amer. Journ. Conch., Vol. 3, p. 261, 1867; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 162, 1928. Ato7na Bellardi, Bolletino della Societa Malacologica Italiana (Pisa), Vol. 1, p. 24, 1875, type (by monotypy) Atoma hypothelica Bellardi; Mem. R. Accad. Scienze Torino, Ser. 2, Vol. 29, p. 324, 1878, type illustrated; Cossmann, Ess. Pal^o. Comp., Vol. 2, p. 126, 1896, type illustrated, pi. 7, fig. 17, Miocene of Italj-; not Atoma Latreille in Cuvier, Regne Anim., Vol. 3, p. 125, 1817. Hxdroplewa (Monterosato MS.) Bucquoy, Dautzenberg, and DoUfus, Moll. Mar. Roussillon, Vol. 1, p. 110, 1883, type (by monotypy), Murex seplangularis Montagu, figured, pi. 14, figs. 26, 27, described by Montagu, Test. Brit., p. 268, pi. 9, fig. 5, 1803, illustrated by Tryon, Man. Conch., Vol. 6, p. 223, pi. 21, fig. 8, 1884, and by Harmer, Mon. Palseo. Soc, Vol. 68, Plio. Moll. Gt. Brit., Vol. 1, p. 251, pi. 27, fig. 27, pi. 29, figs. 3, 4, 1915, Pliocene to Recent from Great Britain to the Mediterranean; Cossmann, Ess. Paleo. Comp., Vol. 2, p. 92, 1896, type illustrated, pi. 6, figs. 14, 15. Type (by monotypy), Mangelia virginiana Conrad, described and figured by Conrad, loc. cit., and pi. 21, fig. 12, originally described in the Proc. Acad. Nat. Sci., Phila., p. 286, 1862; Miocene of Yorktown, Virginia. Shell small ; whorls sculptured with longitudinal ribs of a small or moderate number, otherwise practically smooth; aperture from a third to two-fifths the length of the shell, with a small, mdistinct posterior sinus, a small callus patch at the top of the umer lip, a short columella, and a very short, undefined, notched anterior canal; animal operculate. Geologic range: Miocene to Recent (Europe and America). Distribution : Europe ; west coast of Panama. This genus is intermediate between Mangelia, subgenus Beta, and Clavus. It is smaller than the latter, with a weaker notch. Dall described a Bellaspira melea^ from Panama, but his "? Ha;dro pleura" melita apparently does not belong here. 1 Bellaspira melea DaM, Proc. U. S. Nat. Mus., Vol. 56, p. 29, pi. 19, fig. 8, 1919. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 585 Genus MANGELIA Risso, 1826 Mangelia Risso, Hist. Nat. Eur. M&id., Vol. 4, p. 219, 1826, list includes costidala Risso (not figured), ginnania Risso (fig. 99), striolala Risso (fig. 101), menardiana Risso (fig. 130), and others, some of which were identified by Gray as Rissoina; Herrmannsen, Indicis Generum Malacozoorum, Primordia, Supplement, p. 80, 1852, type cited M. striolala Risso {fide Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 177, 1928). Mahgilia Risso emended, spelling used by many authors. Vielliersia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 128, 1884, type (by monotypy) Pleuroloma I'ielliersi [sic] Michaud, Bull. Soc. Linn. Bord., p. 202, pi. 1, figs. 4, 5, 1829, Mediterranean, with "RaphUoma allenuata Montagu," Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. RoussUIon, Vol. 1, p. 101, pi. 14, fig. 24, 1883, cited by Monterosato in the synonymy. Villiersiella Monterosato, Nat. Sicil., An. 9, p. 191, 1890, new name for Villiersia (the original spelling said to be a typographical error, though the specific name was spelled the same way); not Villiersia Orbigny, 1837. Type (by subsequent designation, Herrmannsen, 1852), Mangelia striolala Risso, op. cit., p. 221, pi. 8, fig. 101, 1826, living and "subfossil" in the Mediterranean, = Pleuroloma vilUersii Michaud, Kiener, Spec. Gen. et Icon. Coq. Viv., Vol. 5, Pleurotome, p. 80, pi. 27, figs. 1, 1840, = Murex atlenualus Montagu, Testacea Britannica, p. 266, pi. 9, fig. 6, 1803. Risso's and Kiener's illustrations are reproduced below, though not very clearly, on plate 25, figures 18 and 19a, 19b. Shell small, thin, elongate, strengthened with a few distant axial ribs which are crossed bj^ many fine spiral striations ; aperture narrow, elongate, outer lip thickened when in the process of forming a rib, sometimes with a single denticle near the upper part separating off an embayment-like posterior notch, hp thm when growing between ribs, with then but a small, romaded, slit-like notch, in species that do not have strong axial ribs the posterior notch sometimes merely a rounded emljajTiient, some- times practically obsolete, inner lip smooth, columella nearly straight, moderately long, anterior canal usually not well defined, short., not notched behmd; animal (always ?) inoperculate. Geologic range: Eocene to Recent. Distribution: All temperate and tropical waters. The nomenclature of this important genus of little shells has been needlessly con- fused. Ball's statement' that Bellardi selected M. costulata as the type in 1847 seems to be entirely unfounded, for in his Monograph of the Fossil Pleurotomas of Piedmont Bellardi- notes the name only in the synonymy. It is possible that Bellardi wrote some- thing else in that year; but as Dall gives no reference to it and as no other reference could be found, it must be regarded for the time being as mythological. However, even if costulata had been cited as the type, it would only cause a reorganization of the subgenera within the genus; for costulata Risso, figured by Kiener,^ is surely congeneric with striolala, even if it is the same as nebula, the type of Bela, as Dall says it is. Therefore, unless more evidence is produced that will lead to some other conclusion, striolata Risso, 1826, (not of Scacchi, 1836) must be accepted as the type. Furthermore, there need be no question about the character of the species striolata, for it will be evident to anyone who compares Risso's figure with Kiener's excellent illus- trations of vilUersii that they represent the same species. Also, a comparison with Mon- tagu's original figure of attenuata will show almost as certainly that it too represents the same species, although some later writers have misidentified attenuata. The name Man- gelia, then, may be considered fixed. The limits of the genus Mangelia are open to debate. Border-line species are diffi- cult to separate from Lora, Cythara, Clathurella, Pleurotomoides, and the young of Clavus. In addition, the genus itself varies into such a number of different forms that it is ' Mangilia Risao, Dall, Proc. U. S. Nat. Mua., Vol. 54, p. 316, 191S. ' Mem. R. Accad. Scicnze Torino, Ser. 2, Vol. 9, pp. 531-650, 1847. ' Pleuroloma costulata Risao. Kiener, Sp^c. G^n. et Icon. Coq. Viv., Vol. 5, Pleurotome , p. 78, pi. 25. figs. 2, 1840. 586 San Diego Society of Natural History [ Memoirs difficult to keep track of them all. Typical Mangelia has a thin, elongate shell with only a small number of axial costae, crossed by many minute spiral lines. Its posterior notch varies according to the stage of growth, being at the time of the formation of one of the varix-like ribs (the form illustrated by Risso and Kieiier) Uke that of the subgenus Agathotoma; but, when growing between ribs, more like that of the subgenus Bela and its section Kurtziella. The typical group varies into Bela, which has a somewhat heavier shell, a somewhat shorter aperture, less distant axial ribs, stronger spiral Unes, and a simple outer lip with an unemphasized posterior notch. The subgenus Mitromorpha grades from the Agathatoma-like species of Bela into a form with biconic shape, occa- sionally having denticles on the inside of the outer lip. The typical group also varies into Agathotoma, which has broader, more wave-Uke axial ribs covered with numerous, more prominent, though still fine, spiral threads, a much shorter anterior canal, and a pos- terior notch that sinks deeply into the thickened edge of the outer lip. The section Pseudoraphitoma has a high spire and a row of denticles on the inside of the outer lip in addition to the fold that occurs sometimes in typical Mangelia just below the notch. Mangelia is a warm or temperate water genus, whereas Lora is typical of cold waters. All of the species from the Alaskan region that have been assigned to Mangelia are open to question, and according to their shell characters should probably be assigned to Lora, whether with or without an operculum. Lora can usually be distinguished by its larger size, its greater relative breadth, its more numerous axial ribs, and its stronger spiral lines. Also, the aperture is usually more open, and the posterior notch weaker, shallower, and farther from the suture. The intergradation between Mangelia and Lora may be more apparent than real, for the two may be adaptations of different branches of the family to analogous environmental conditions. On the other hand, the intergradation between Mangelia and the genera Cythara, Clathurella, and Raphitoma is probably real. Cythara is like Agathotoma except that it is larger, has a heavier shell, a short, blunt spire, and numerous teeth on both sides of its long, narrow, nearly straight aperture. Clathurella is like Agathotoma except that it is larger, has a blunter spire, coarse rounded axial ribs, and a few strong teeth on the inside of the outer Up. Raphitoma is Uke Agathotoma except that it is larger, has more rounded whorls with sharp reticulate sculpture, and at certain growth stages faint teeth on the inside of the outer lip. The subgenus Bela is related closely to Clavus through the small species of Cymato- syrinx. Indeed, some of the young of small species of Cymatosyrinx, like C. {Cymato- syrinx) thalea (Dall) from Florida, can hardly be distinguished from M. (Bela) nebula until the former becomes large enough to develop the callus patch at the top of the inner Up and to show its deeper anterior and posterior notches. Bellaspira, with its probable synonym Hoedropleura, is intermediate in some respects between Bela and Cymatosyrinx, having a larger, heavier, and coarser shell than Bela, a callus on the inner Up, and an operculum; but it is smaller than a normal Cymatosyrinx and has a shallow posterior notch. Subgenus MANGELIA, s. s. Shell thin, elongate ; whorls sculptured with a few narrow, distant axial ribs, spirally marked with fine Imes; aperture elongate, narrow, outer hp at some stages of growth thickened by a rib, the pos- terior notch rounded, not very deep, sometimes emphasized by a fold or denticle situated just below it on the inside of the outer hp, at other stages of growth outer lip thin, the notch small, rounded, of variable depth, not emphasized by a fold, columella nearly straight, anterior canal not well defuied, merely an elongation of the narrow aperture, fairly long, not notched behind; animal inoperculate. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 587 Mangelia (Mangelia) hexagona Gabb Mangelia hexagona Gabb, Proc. Calif. Acad. Sci., Ser. 1, Vol. .3, p. 18.5, 1865; Berry, Nautilus, Vol. 21, p. 40, 1907. Mangilia (Cythara) hranneri Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 211, pi. 9, fig. 10, 1903. Mangilia hexagona Gabb, Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 44, 1916. Cytharella hexagona Gabb, DaU, Bull. 112 U. S. Nat. Mus., p. 82, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 145, 1927. Cytharella branneri ,\rnold, DaU, Bull. 112 U. S. Nat. Mus., p. 82, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 10, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Cytharella (Agalhotoma) quentinensis DaU, West Amer. Scientist, Vol. 19, no. 3, p. 21, 1921. Agathotoma quentinensis DaU, Proc. U. S. Nat. Mus., Vol. 66, Art. 17, p. 2, pi. 8, fig. 1, 1925. Shell small, thin, very elongate; whorls sculptured with six fairly sharp, strong ribs, nearly straight, continuous up the spire, ribs and interspaces crossed by very mmute spiral Imes; aperture varying in length from one-third to two-fifths the length of the shell, elongate, outer hp very thin except when formmg a rib, posterior notch nearly obsolete, columella nearly straight, anterior canal not defined, merely an elongation of the aperture, moderately wide, very, very slightly notched or sometimes bent backward. Dimensions : Altitude, 9 mm. ; length of aperture, 3.4 mm. ; diameter of body whorl, 2.6 mm. Type specimens: Of hexagona, locality unknown; of branneri, No. 162,552, of quen- tinensis. No. 333,134, in the U. S. National Museum. Type localities: Of hexagona, "one specimen from Catalina Island, 40 fms., another from the beach at Monterey;" Oldroyd, 1927, selects the first locality; of branneri, lower San Pedro Pleistocene of Deadman Island, Calif.; of quentinensis, "? Pliocene" of San Quintin Bay, Lower CaUfornia. Upper Pliocene: "Pleistocene" at Bath-house Beach, Santa Barbara (Arnold); Fourth and Broadway, Los Angeles (Moody). Pleistocene: Lower San Pedro series of Deadman Island (Arnold), of Nob HiU cut, San Pedro (T. S. Oldroyd), Los Angeles Co., Calif., common; San Quintin Bay, Lower California (Dall; Jordan). Living: Monterey to San Diego; Panama (DaU). This species is easily distinguished by its six sharp, distant, longitudinally connected ribs, and to the naked eye otherwise smooth surface. It is more elongate and has finer spiral and sharper axial sculpture than aculea Dall. Gabb's dimensions show that his shell had a slighth' longer aperture than branneri or quentinensis, and one small living specimen in the Oldroyd Collection at Stanford University agrees. Nevertheless, most of the living specimens have the shorter aperture, and the writers believe this character to be but an individual variation. Mangelia (Mangelia) merita (Hinds) Clavatula merita Hinds, Proc. Zool. Soc. London, p. 42, 1843; Zool. Voy. Sulphur, MoU., pi. 6, fig. 20, 1844. Pleurotoma merita Hinds, Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 18, species 148, December, 1843. Clathurella merita Hinds, Tryon, Man. Conch., Vol. 6, p. 280, pi. 18, fig. 32, 1884. Cytharella ? janira DaU, Proc. U. S. Nat. Mus., Vol. 56, p. 76, pi. 21, fig. 10, 1919. Cytharella amalula DaU, Proc. U. S. Nat. Mus., Vol. 56, p. 78, pi. 21, fig. 2, 1919; BuU. 112 U. S. Nat. Mus., p. 82, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 147, 1927. Cytharella merita Hinds, DaU, Bull. 112 U. S. Nat. Mus., p. 82, 1921; Oldroyd, Stanford Univ. Publ. Geol., \o\. 2, Pt. 1, p. 147, 1927. Cytharella (Agathotoma) janira DaU, BuU. 112 U. S. Nat. Mus., p. 83, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 148, pi. 19, fig. 7, 1927. Shell of medium size and weight, fusiform; whorls strongly convex or with an obtuse angle on the upper part, sculptured ^ath nine to eleven broad, romided axial riblets, crossed by numerous fine spiral threads and grooves, the thread on the angle usually a little stronger and m living specimens sometimes colored bro^NTi, aperture of variable length, usually about half the length of the shell, narrow, lenticular, outer hp thickened by a rib or thin according to the growth stage, posterior notch also varymg according to the grow1;h stage, at tunes very shallow, at other times deep and narrow but not reinforced, imaer Up resorbed, columella elongate, anterior canal merely an elongation of the aperture. 588 San Diego Society of Natural History [ Memoirs Variety merita, s. s. Shell comparatively short. Dimensions: Altitude, 11 mm.; length of aperture, 5.5 mm.; diameter of body whorl, 4.2 mm. Type specimens: Of merita, in the British Museum (?); of janira, No. 55,285, of amatula, No. 127,534a, in the IT. S. National Museum. Type localities: Of merita, Gulf of Nicoya, Central America; oi janira and amatula, San Diego. Distribution: Monterey to the Gulf of Nicoya. Mangelia (Mangelia) merita (Hinds) variety painei Arnold Mangilia painei Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 214, pi. S, fig. 1, 1903; not "Mangilia painei Arnold," Dall, 1919. Shell comparatively elongate, with a relatively longer columella and anterior canal, whorls without angulation. Dimensions: Altitude, 12 mm.; length of aperture, 6.1 mm.; diameter of body whorl, 4.2 mm. Type specimen: No. 162,530 in the U. S. National Museum. Type locality: Lower San Pedro Pleistocene of Deadman Island, San Pedro Harbor, Los Angeles County. Pleistocene: Type locality. Living: Specimens in the Oldroyd Collection at Stanford University from Monterey and San Diego. The variety painei is one extreme among a number of others equally distinct that terminate the several series of variations in this rather variable species. Living examples that agree in every essential with Arnold's illustration and description of painei are to be found in the Oldroyd Collection at Stanford University under various labels. Other var- iations appear in the collection, one with stronger tabulation and more glistening surface labeled hamata Carpenter, one with a heavier shell labeled fusconotata Carpenter (this form described originally as a Cithara), and another included under the label amatula Dall with a short aperture and a higher spire. The last may be the form described under the name Mangilia (Kurtziella) hebe Dall, 1919, the illustration of that form showing an individual in the interrib growth stage. The writers did not have sufficient material to determine the proper application of Carpenter's names. The species merita forms a link between Mangelia, s. s., and Agathotoma, resembling the latter in some respects more closely. It is quite distinct from hexagona, having a less elongate shell with more numerous, more rounded, less distant axial ribs not continuous up the spire, and in the rib-forming growth stage with a more distinctly thickened outer lip. It is to be noted that both in Agathotoma and in Mangelia, s. s., the ribs when few in number tend to be continuous up the spire, but when more numerous they more often become irregular. This species is assigned to typical Mangelia instead of to Agathotoma because the outer lip is thickened only part of the time and then not strongly, and be- cause the columella is longer than is usual for Agathotoma and the ribs more rounded than wave-like. In the growth stages when the notch is shallow this species might be mistaken for a species of the subgenus Bela, such as the higher-spired variations of hecetce. M. merita is a strong argument for not separating the subgenera of Mangelia into distinct genera. VoLCME I ] Pliocene and Pleistocene Mollusca of California 589 Subgenus BELA Leach in Gray, 1847 Beta Leach, Gray, Ann. and Mag. Nat. Hist., Vol. 20, p. 270, 1S47, specie.? in the original list are nehtla, rufa, cranchii, minima, septangularis and atlewtala, all of Montagu; Proc. Zool. Soc. London, \i. 134, 1847, type designated, Miirex nebula "Montf." (probably a misprint for Montagu); Iredale, Proc. Malac. Soc. London, Vol. 11, p. 297, 1915; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 318, 1918; Woodring, Carnegie Inst. Wash., Publ. No. 385, pp. 178, 179, 1928. Not "Bela Gray," as used erroneously by many authors for Lora, the error pointed out by Harris, Iredale, and others (see Lora). Ciitliarella Monterosato, Boll. Societa Malacologica Italiana (Pisa), Vol. 1, p. 73, 1875, type (by monotypy) Miirex costatus Donovan, Nat. Hist. Brit. Shells, Vol. 3, pi. 91, January, 1802, well described and illustrated by Forbes and Hanley, Hi.st. Brit. Moll., Vol. 3, p. 485, pi. 114A, figs. 3, 4, 5 (in Vol. 4), pi. RR, fig. 4 (animal, —in Vol. 1), 1853; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 168, 1928. Mangiliella, Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, p. 108, 1883, type (by monotypy) Pleuroloma muUilineolala Deshayes, figured by B., D., and D., op. cil., pi. 15, figs. 23, 24, 25, also by Coss- mann. Ess. Pal^o. Comp., Vol. 2, p. 119, pi. 7, fig. 13, 1896, Mediterranean. Ginnania Monterosato, Nom. Gen. Spec. Conch. Medit., p. 127, 1884, type (by absolute tautonymy) Pleuroloma fuscata Philippi, of which Monterosato said, "Designata col nome di Oinnania, Risso (sp. dubbia); Ginannia Sc; Gimianianum, Ph., e riferita alia nebula, Mtg., forma dei mari del Nord." Monterosato evidently didn't agree that /uscata should be referred to nebula, for he cites in the synonymy oi fuscata "Raphitoma nebula, (non Mtg.) B., D. e D.," Moll. Mar. Roussillon, Vol. 1, "pi. 14, figs. 22, 23," 1883. Smithia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 128, 1884, type (by monotypy) Pleuroloma striolata Scacchi (not Risso) with P. costala (non Pennant) Blainville, Faune Franc, p. 103, pi. 4, fig. 6 (Medit.), and P. smithii Forbes (Britain) listed in the synonymy, species illustrated by Forbes and Hanley, Hist. Brit. Moll., Vol. 3, p. 483, pi. 114A, figs. 1, 2 (in Vol. 4), 1853, and smithii Forbes, Ann. [and Mag.] Nat. Hist., Vol. 5, p. 107, pi. 2, fig. 14, 1840, also by Reeve, Conch. Icon., Vol. 1, Pleuroloma, pi. 35, species 320, 1846; not Smithia Edwards and Haime, 1851, nor Maltzan, 1883. Smithicllia Monterosato, Nat. Sicil., An. 9, p. 186, May 1, 1890, new name for Smithia; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2, p. 766, 1898; Iredale, Proc. Malac. Soc. London, Vol. 13, p. 32, 1918; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 331, 1918. Smithiella Monterosato, Kobelt, Icon. Eur., Vol. 3, p. 381, 1905. Not "Cytharella Monterosato" Dall, Proc. U. S. Nat. Mus., Vol. 54, pp. 320, 325, 1918, etc., type Pleurotoma bertrandi Payraudeau, not in Monterosato's original list (Dall's reference to p. 6 is to a separate of Monterosato's paper) ; = Agathotoma. Type (by subsequent designation, Gray, 1847), Murex nebula Montagu, fossil in the Red Crag and living from the North Sea to the Mediterranean, illustrated by Forbes and Hanley, Hist. Brit. Moll., Vol. 3, p. 476, pi. 114, figs. 7, 8, 9 (in Vol. 4), pi. RR, fig. 7 (animal, — in Vol. 1), 1853; by Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 23, species 198, 1845 (poor figure); and by Tryon, Man. Conch., Vol. 6, p. 307, pi. 21, figs. 21, 10, pi. 30, fig. 86, pi. 33, fig. 56, 1884. Shell like that of the typical subgenus, but slightly heavier, with less distant a.xial ribs, the ribs not always continuous up the spire, sometimes low, rounded, or curving, whorls sometimes angulated, posterior notch usually weak. This subgenus is closely related to the typical subgenus, with which it intergrades in Europe; but it is fairly distinct on the California coast, where the typical subgenus is poorly represented. It intergrades also with the subgenus Agathotoma; and the border- line species that have a shorter anterior canal and a slightly thickened outer lip are as- signed arbitrarily to Agathotoma. Bela bears a superficial resemblance to some small Pyrenids, especially Aesopus and Chauvetia, but the latter lack the posterior notches, have a twisted columella or a notched anterior canal and an operculum. The elongate, round- whorled species are included in the section Bela, s. s.; the elongate, angulated species in the section Kurtziella; and the broader, Lora-like species in the section Ishnula. Section Bela, s. s. Shell high spired, with rounded whorls and low, rounded ribs. 590 San Diego Society of Natural History i .Memoihs Mangelia (Bela) variegata Carpenter Mangelia variegata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 658, 1864; Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 394, 1865; descriptions reprinted in Smithsonian Misc. Coll., No. 252, pp. 144, 284, 1872. Mangelia (? mriegalo, var.) niiens Carpenter, same references. "Daphnella interfossa Carpenter," Tryon, Man. Conch., Vol. 6, p. 310, pi. 22, fig. 57, 1884. "Mangilia striosa C. B. Adams," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 215, pi. 9, fig. 3, 1903. Mangilia oenoa DaU, Proc. U. S. Nat. Mus., Vol. 56, p. 66, pi. 8, fig. 6, 1919 (young); Bull. 112 U. S. Nat. Mus., p. 81, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 138, 1927. Cytharella (Agathotojna) densilineata Dall, Bull. 112 U. S. Nat. Mus., p. 83, 1921, new name for "striosa" Arnold; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 149, 1927. Mangilia jndchrior Dall, Bull. 112 U. S. Nat. Mus., pp. 81, 201, 1921, new name for nitens Carpenter "not Sowerby," new name not necessary, for there is no nitens Sowerby and the only prior nitens is Clavatula nitens Hinds, which is clearly a Clavus (Cymatosyrinx), not a Mangelia; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 139, 1927. Shell high spired, thin ; whorls moderately rounded or very slightly angulated at the upper part, sculptured with nine to fifteen narrow, somewhat curved axial ridges crossed by numerous fine spiral striations, the ribs on the body whorl being fewer and more rounded than those of the spire ; aperture lenticular, elongate, about two-fifths the length of the shell, outer hp thm, posterior notch a shallow, arcuate sinuosity m the edge of the outer lip just above the point of greatest convexity of the whorl, best shown by the curvature of the axial ribs, columella only very sUghtly flexuous, anterior canal moderately long, not defined, not notched behind; Hving shells with one (or two) narrow color bands about the middle of the body whorl. Dimensions: Altitude, 10 mm.; length of aperture, 4 mm.; diameter of body whorl, 3.3 mm. Type specimens: Of variegata and nitens (+ pulchrior), in the British Museum (?); of densilineata, at Stanford University (?) ; of oenoa, No. 153,051 in the U. S. National Museum. Type localities: Of variegata and nitens, Santa Barbara, living; of densilineata, "upper San Pedro" Pleistocene of Los Cerritos, Los Angeles Co., Calif. ; of oenoa, San Pedro, living. Pleistocene: Type locality of densilineala (Arnold), also from San Diego (Arnold); Santa Monica (Oldroyd Collection at Stanford University); upper Pleistocene of San Quintin Bay, Lower California (Jordan). Living: Monterey, Calif., to the Gulf of California. The name variegata is not preoccupied by Pleurotoma variegata Kiener, which is a Turricula over three inches long, nor by "Pleurotoma variegata Kiener" Reeve, which is a typical Turris, nor by Pleurotoma variegatum Philippi, which is a Raphitoma, a synonym or variety of purpurea (Montagu). Also, it appears, as noted in the synonymy, that Car- penter's varietal name is still good. Hence, unless new instances of the use of these names are found, there is no need for Ball's 1921 substitute names. Unfortunately, the identification of the older names is uncertain, for Carpenter's descriptions are brief and rather unsatisfactory, and there are no figures. It is hoped that some day the types can be found and made known. Apparently Carpenter's types were young, unusually narrow shells, the length being over three tin.es the breadth; and the type of variegata is described as having only nine axial ribs, whereas most specimens have more. In the Oldroyd Collection at Stanford University there is one specimen with ten ribs on the body whorl, several with eleven, and the normal number seems to be twelve. Nearly all the specimens have more ribs on the penultimate whorl than on the body whorl, though the number is less again on the early whorls. Thus it is that Dall's type of oenoa, which is an immature shell, has an unusually large number of ribs. Occasionally a speci- men will retain its numerous ribs even on the last whorl, apparently never reaching a gerontic stage. In other respects the forms here included under the name variegata agree Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 591 very well with one another and with Carpenter's descriptions, even to the matter of color markings; and as the number of ribs has been shown to be a very variable character in this species, it is considered most probable that Carpenter had an unusual variation with the minimum number of ribs. It is interesting to note that he mentions having other speci- mens with more numerous ribs. The variety nitens does not appear to be distinguishable. An interesting observation was made on the protoconch of this species. Nearly all of about a dozen specimens examined had two or two and a half smooth, rounded, bulging whorls. One specimen, however, had all but a very small, depressed first whorl spirally striated, and these striations were crossed by rudimentary axial irregularities. This odd specimen contrasted very strikingly with the others, and the writers began to speculate about the value of protoconchs for making generic and specific separations when another specimen was discovered that provided the explanation. Most of its protoconch was smooth as in the majority of the others, but near the suture in places that had been partly protected from wear were remnants of the almost entirely removed outer layer. Mangelia (Bela) hooveri Arnold Mangilia hoovcn Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 212, pi. 9, fig. 5, 190.3; Dall, Bull. 112 U. S. Nat. Mus., p. 80, 1921. Like the last, but with low, broad, roimded ribs, nearly straight, about ten to a whorl. Dimensions : Altitude, 10.9 mm. ; length of aperture, 4 mm. ; diameter of body whorl, 3 mm. Type specivien: No. 162,531 in the U. S. National Museum. Type locality: Upper San Pedro series, Pleistocene, of San Pedro, California. Pleistocene: Type locality (Arnold); San Diego (Dall). This form may be a variety of variegata; or perhaps it is the typical form of variegata, and oenoa and densilineata are a variety with more numerous ribs. The forms vary in the shape and in the number of ribs, and it is a question which character, if either, is significant. Probably hooveri should not be regarded as an extinct species. Mangelia (Bela) perattenuata DaU Columbella (Aesopus) oldroydi Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 238, pi. 6, fig. 7, 1903, not Mangilia oldroydi Arnold, op. cii., p. 213, pi. 6, fig. 16 ( = ? Lora declivis var. ecannata Sars, which see). Ma{n)gilia peraltenuata Dall, Nautilus, Vol. 18, p. 123, 190.5; Proc. U. S. Nat. Mus., Vol. 56, p. 65, pi. 20, fig. 11, 1919; BuU. 112 U. S. Nat. Mus., p. 81, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 1, p. 139, 1927. Mangilia cetolaca Dall, Bull. Mus. Comp. Zool., Harvard CoU., V^ol. 43, p. 286, 1908; new name for Aesopus oldroydi Arnold; Bull. 112 U. S. Nat. Mus., p. 80, 1921. Philbertia (Nannodidla) phylira Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 60, pi. 20, fig. 6, 1919, young. Philbertia (f Nannodiella) amyela DaU, Proc. U. S. Nat. Mus., Vol. 56, p. 61, pi. 20, fig. 8, 1919, younger. Shell small, very elongate; whorls not very convex, early whorls sculptured with ten to fifteen narrow, distant a.xial riblets, their number mcreasing on each succeeding whorl, and with one to three similar, sharp, distant spiral riblets, their number also increasing with the gro\\i,h of the shell, ribs and spirals nodulous where they cross, sculpture nearly obsolete m adult specimens and the dehcate sculpture of the earlier whorls usually almost obUterated by wear; aperture short, narrow, less than a third the length of the shell, outer lip thin, simple, posterior notch weak, merely a waving of the growth hnes above the uppermost spiral, columella short, sliced off obhquely at varyuig angles near the end, anterior canal short, not defined. Dimensions : Altitude, 8 mm. ; length of aperture, 2.3 mm. ; diameter of body whorl, 2.3 mm. Type specimens: All in the V. S. National Museum except that of cetolaca, which cannot be found; that of phylira, No. 274,108, that of amyela. No. 216,944. 592 San Diego Society of Natural History [ Memoirs Type localities: Of perattenuata, living, Monterey Bay; of cetolaca, lower San Pedro, Pleistocene, of Deadman Island, Los Angeles Co., Calif.; of phylira, Panama; of amyela, Panama. L. Pleistocene: Lower San Pedro series of Deadman Island, Los Angeles Co. (Arnold). Linng: Monterey to Panama. This species has received a large number of names because of its different appearance when young; but there is in the Oldroyd Collection at Stanford University a series of specimens from Lower California showing the different growth stages, and on one nearly adult specimen the early sculpture is almost all preserved. Dall mentions that phylira "superficially resembles 'Aesopus' oldroydi Arnold," but the resemblance is more than superficial. Dall compares this species to Mangelia constricta Gabb, a species from Cata- lina Island that has never been figured,' but the latter has a shorter shell and a deeper notch. The species of Nannodiella to which Dall compares the young forms have smaller shells than the young of perattenuata, with deeper notches showing in the growth lines of the spire whorls, and stronger angulations; and even without the apertures they would be recognizably different. M. perattenuata is most closely related to M. variegata and M. hooveri, but it has a slenderer shell and a different sculpture. Mangelia (Bela) interlirata Stearns Mangelia interlirata Stearns, Proc. Calif. Acad. Sci., Vol. 4, p. 226, pi. 1, fig. 10, 1872; Baker, Nautilus, Vol. 16, p. 41, 1902. Mangilia interlirata Stearns, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 213, pi. 6, fig. 15, 1903; DaU, Bull. 112 U. S. Nat. Mus., p. SI, 1921 ; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 143, 1927. Mangilia interfossa var. pedroana Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 213, pi. 6, fig. 3, 1903; Dall, Bull. 112 U. S. Nat. Mus., p. 82, 1921. Mangilia cesta Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 71, pi. 21, fig. 7, 1919; Bull. 112 U. S. Nat. Mus., p. 80, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 137, 1927. Shell small, elongate; whorls moderately rounded, sculptured by eight to ten strong, rounded axial ribs with wider interspaces and by ten to twelve revolving grooves also with wider mterspaces, the grooves showing only between the ribs and on the lower part of the body whorl; aperture short, about a third the length of the shell, rounded at the posterior end, with a shallow posterior notch, aperture wider anteriorly, outer lip slightly thickened at the rib stage, columella straight, canal not defined. Dimensions: Altitude, 9 mm.; length of aperture, 3 mm.; diameter of body whorl, 3 mm. Type specimens: In the U. S. National Museum, that of pedroana No. 162,532, that of cesta No. 209,040; for interlirata, fide Oldroyd. Type localities: Of interlirata, Monterey Bay; of pedroana, lower San Pedro Pleisto- cene of Deadman Island; of cesta, San Pedro. U. Pliocene: Santa Barbara (Arnold). Pleistocene: Lower San Pedro series of Deadman Island, Los Angeles Co. (Arnold) ; upper San Pedro series of Los Cerritos, Los Angeles Co. (Arnold). Limig: Monterey to Catalina Island, California. This species resembles the typical subgenus in sculpture, but has a heavier shell and shorter aperture. It has stronger sculpture than perattenuata and a shorter aperture and columella than variegata. Its short columella is more like that of Agathotoma, but it does not have the wave-like ribs nor the heavy outer lip of the latter. It resembles M. crass- aspera and its relative rhyssa, but the more numerous spiral lines do not cross the ribs, and it has a higher spire than crassaspera. The form figured by Arnold as interlirata has an unusuallv small number of ribs. 1 Mangelia constricta Gabb, Proc. Calif. Acad. Sci., Ser. 1, Vol. 3, p. 84, 1865. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 593 ? Section Ishnula Clarke in Gray, 1847 Ishnula Clarke, Gray, Proc. Zool. Soc. London, p. 134, 1847; Iredale, Proc. Malac. Soc. London, Vol. 11, p. 299, 191.5; see also Lora. Type (by monotypy), Mangelia menardiana Risso, Hist. Nat. Eur. Merid., Vol. 4, p. 222, pi. 9, fig. 130 (explanation of figure on p. 437), 1826, figure reproduced herewith, plate 25, figure 21. Like the typical subgenus but somewhat angulated and relatively shorter and broader. Iredale was wrong in stating that "Gray indicated Clarke's name as an absolute synonym" of Bela, for Gray named it on a separate line, his method of treating subgenera, and in addition he placed it behind a question mark. Mangelia (Bela) crebricostata Carpenter Mangelia crebricostata Carpenter, Brit. Assn. Adv. Sci., Rept. for 186.3, pp. 628, 658, 1864; Ann. and Mag. Nat. Hist., Ser. 3, Vol. 1.5, p. 28, 1865; these publications reprinted in Smithsonian Misc. Coll., No.252, pp. 114, 144, 242 (bottom pagination), 1872. Mangilia crebricostata Carpenter, Dall and Bartsch, Victoria Memorial Museum, Bull. Xo. 1, p. 140, pi. 10, fig. 3, 1913; Dall, Bull. 112U. S. Nat. Mus., p. 82, 1921; Oldroyd, Univ. Wash. Puget Sound Biol. Sta., Vol. 4, p. So, 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 145, Pt. 2, pi. 61, fig. 3, 1927. Mangilia newcombei Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 71, pi. 21, fig. 4, 1919; Bull. 112 U. S. Nat. Mus., p. 81, 1921; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 83, 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 141, 1927. Shell of medium size or large for a Mangelia, spire moderately high; whorls rounded, with a slight angulation near the top, sculptured with about fifteen flexuous, low, rounded axial ribs, crossed by numerous small spiral Imes, which are more prominent in the interspaces; aperture bluntly ovate, less than half the length of the shell, outer lip simple, posterior notch represented by a backward curvmg of the lip, the deepest point being near the angulation, columella moderately long, slightly sliced off at the end, anterior canal poorly defined, not long; animal inoperculate. Dimensions: Altitude, 12 mm.; length of aperture, 5.5 mm.; diameter of body whorl, 4.2 mm. Type specimens: In the U. S. National Museum, that of newcombei No. 150,965. Type localities: Of both, Vancouver district; of crebricostata, Neah Bay, Washington (fide Oldroyd); of nexocombei, Clayoquot Sound, Vancouver. Laving: Vancouver to Monterey, California; also Alaska, according to Dall, but this record questioned. This species resembles somewhat M. variegata, but it has a broader shell and stronger ribs. It is strikingly like the type illustration of Mangelia menardiana Risso, and for this reason the name Ishnula is introduced here, although it is not believed that the sections of Bela have any significance, Kurtziella being no better than Ishnula. M. crebricostata is distinguishable from M. hecetoe by its curving, more numerous ribs. It very much re- sembles a small specimen of Lora pyramidalis, and the report of this species in Alaska may be a misidentification of a small Lora. Mangelia (Bela) hecetae Dall and Bartsch Mangelia angulala Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 603, 658, 1864; Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. .395, 1865; these publications reprinted in Smithsonian Misc. Coll., No. 252, pp. 89, 144, 284, 1872; Keep, West Coast Shells, p. 55, 1888, 1892; not Mangelia angulata Reeve, Conch. Icon., Vol. 3, Mangelia, pi. 8, species 62, 1846. Mangilia angulata Carpenter, Cooper, Bull. No. 4, Calif. St. Mining Bureau, p. 27, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 212, pi. 7, fig. 9, 1903; T. S. Oldroyd, Nautilus, Vol. 28, p. 81, 1914; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 43, 1916; Dall, Bull. 112 U. S. Nat. Mus., p. 79, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus.. Vol. 65, Art. 22, p. 10, 1925; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. 594 San Diego Society of Natural History [Memoirs Mangilia hecetx Dall and Bartsch, Canada Dept. Mines, Geol. Surv. Branch., Memoir No. 14-N, p. 10, pi. 1, fig. 6, 1910; Dall, Bull. 112 U. S. Nat. Mus., p. 81, 1921; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 84, pi. 12, fig. 6, 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 141, pi. 11, fig. 8, 1927. Mangilia [Kurlziella f) beta Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 64, pi. 22, fig. 4, 1919, (young). Compare Lora antiyoda Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 41, pi. 19, fig. 1, 1919. Mangilia beta Dall, Bull. 112 U. S. Nat. Mus., p. 80, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 136, 1927. Mangilia barbarensis Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 82, 1924; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 132, September, 1927, new name for angulata Carpenter not Reeve. Shell of medium size, with a moderately high spire ; whorls definitely but obtusely angulated near the top, sculptured with 12-14 rather narrow axial ribs, which pass nearly straight across the shelf and fall off almost vertically below the angle, interspaces and sometimes the ribs crossed by numerous very fine spiral lines which are usually not evident to the naked eye; aperture about half as long as the shell, ovate, with the posterior end blmited by the angulation and the anterior end drawn out mto a rather narrow but short and poorly defined anterior canal, outer lip thin, the notch coming at the angle or a little above, hardly noticeable ; animal inoperculate. Dimensions: Altitude, 11 mm.; length of aperture, 5.5 rmn.; diameter of body whorl, 4.5 mm. Type specimens: Of angulata = barbarensis, in the British Museum (?); of hecetoe, in the collection of the Canadian Geological Survey at Ottawa (fide Oldroyd); of beta, No. 206,554, of antipoda, No. 209,450, in the U. S. National Museum. Type localities: Of angulata = barbarensis, Santa Barbara; of hecetce, Barkley Sound, Vancouver Island; of beta. Point Aiio Nuevo, middle California; of antipoda, Magellan Strait, South America. U. Pliocene: Santa Barbara (Arnold); Fourth and Broadway, Los Angeles (Moody). L. Pleistocene: Lower San Pedro series of San Pedro and Deadman Island, Los Angeles Co.; Barlow canyon, Ventura Co. (Arnold); "Saugus," Ventura Co. (Waterf aU) ; loo. 233 S. D. S. N. H., north of Arroyo Santa Rosa, Ventura Co., numerous (U. S. G.) ; loc. 244, Sexton Canyon, Ventura Co., one specimen (U. S. G.) ; Iocs. 247, 249, 250, north of Ventura, several specimens (U. S. G.) . U. Pleistocene: Upper San Pedro series of the vicinity of San Pedro (Arnold; T. S. Oldroyd); San Diego (Arnold) ; San Quintin, Lower California (Jordan) ; Santa Monica, numerous (Oldroyd Collection) ; loc. 74, S. D. S. N. H., near Goleta, Santa Barbara Co. (U. S. G.). Living: Vancouver Island to the Gulf of California. This common and well-known species has for many years been referred to under the name angulata, and it is unfortunate that that appropriate name was preoccupied. M. barbarensis was proposed to replace it, but there ai"e at least two earUer names that must be considered ahead of barbarensis. Probably Dall and Bartsch did not know that Car- penter and others had reported angulata from the Vancouver district, for they say that hecetoe does not agree with any species previously described from that region. The South American antipoda is here referred to merely to call attention to its striking similarity to beta, the young of hecetce. This species varies considerably in the width of the body whorl and somewhat in the number of ribs. The specimen figured by Arnold has unusually few ribs. The taller varia- tions with weaker angles resemble variegata but are larger and broader, with stronger ribs. M. crehricostata is distinguished by its weaker angle and curving ribs, but like variegata probably intergrades. M. arteaga has a sharper angle, sharper sculpture, and a deeper notch. Lora turricula variety popovia Dall differs only in its stronger spiral sculp- ture and its operculum. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 595 Section Kuhtziella Dall, 1918 Kurtziella Dall, Proc. Biol. Soc. Wash., Vol. 31, p. 137, 1918. Type (by original designation), Pleurotottia cerina Kurtz and Stimpson, Atlantic coast; figured by Tryon, Man. Conch., Vol. 6, p. 310, pi. 22, fig. 43, 1884; the form of the growth lines shown by Dall, Bull. 37 U. S. Nat. Mus., pi. 44, fig. 16, 1889. Shell like that of the tj^jical section of Bela but -with a sharper angle and a more evident pos- terior notch. Probably nothing is gained by separating this section from Bela. It only obscures evident interrelations of the species. Mangelia (Bela) arteaga DaU and Bartsch Mangilia arteaga Dall and Bartsch, Canada Dept. Mines, Geol. Surv. Branch., Memoir No. 14-N, p. 11, pi. 2, fig. 4, 1910; Dall, Bull. 112 U. S. Nat. Mus., p. 81, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 10, 192.5; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 84, pi. 13, fig. 4, 1924; Stan- ford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 140, 1927. Shell of moderate size, with medium or high spire; whorls sharply angulated, the shelf above lieing almost flat or only slightlj' convex, sloping at a low angle, the side of the whorl below sloping inward, whorls sculptured with about ten sharp axial ribs with wider interspaces, very slightly curv- ing below the angle but showing the trace of the notch above, and with a few sharp, distant spiral lines, the strongest on the angle, makmg the ribs shghtly nodulous; aperture hah or a little less than half the length of the shell, elongate-ovate, the posterior end beveled by the angulation, the anterior drawn out into a fairly narrow but poorly defined and rather short anterior canal, outer lip simple, with a distinctly indented, rounded posterior notch above the angle, columella nearly straight, moderateh' long; animal moperculate. Variety arteaga, s. s. Shell with only a moderately high spire, aperture nearly half as long as the whole shell. Dimensions: Altitude, 10.25 nun.; length of aperture, 4.6 mm.; diameter of body whorl, 4 mm. Type specimen: In the collection of the Canadian Geological Survey at Ottawa. Type locality: Barkley Sound, Pacific side of Vancouver Island. Pleistocene: Lower San Pedro of Nob Hill cut, San Pedro, Los Angeles Co., Calif. (T. S. Oldroyd). lAving: Vancouver Island to San Diego. MangeUa (Bela) arteaga DaU and Bartsch variety roperi Dall "Mangilia sciilpturata Dall," Taylor, Nautilus, Vol. 7, p. 101, 1894; Lowe, Nautilus, Vol. 13, p. 29, 1899; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 214, pi. 6, fig. 17, 1903; Berry, NautQus, Vol. 21, p. 40, 1907; Gripp, Nautilus, Vol. 22, p. 135, 1909. Mangilia {Kurtziella) arteaga roperi DaU, Proc. U. S. Nat. Mus., Vol. 56, p. 64, pi. 22, fig. 5, 1919. Mangilia arteaga roperi Dall, Bull. 112 U. S. Nat. Mus., p. 81, 1921; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 140, 1927. Shell like that of the typical variety, but with a higher spire and shorter aperture. Dimensions: Altitude, 8 mm.; length of aperture, 3 mm.; diameter of body whorl, ;3 mm. Type specimen: No. 150,993 in the U. S. National Museum. Type locality: Monterey, California. Pleistocene: "Pliocene" and lower San Pedro series of Deadman Island, Los Angeles Co., California (Arnold) ; of San Quintin Bay, Lower California (Jordan). Living: Monterey, California to Cape San Lucas, Lower California (Dall); ? Vancouver Island (Taylor). There is little point in separating the variations of this species into varieties, for most of the other Mangelias have a similar long and a short form; but it is interesting to note, 596 San Diego Society of Natural History [ Memoirs if true, that the more southerly individuals of arteaga are more often slender than the northern ones. The Lora sculpturata Dall, for which this species was mistaken by a num- ber of the earlier conchologists, is a larger, heavier, Alaskan shell with coarser sculpture and an operculum. This species is distinguished from the other species of Mangelia by its strong angle and sharp sculpture. Besides the species of the subgenus Bela here considered, the writers are inclined to include also "Mangilia {Kurtziella)" cyrene Dall, 1919, with its probable synonym "Mangilia {Kurtziella)" dance Dall, 1919, and "/ Mangilia'" dejanira Dall, 1919, the last of which would probably fit best in Bela, s. s. Subgenus MITROMORPHA Adams in Carpenter, 1865 Mitromorpha A. Adams, Carpenter, Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 182, February or March, 1865; Iredale, Proc. Malac. Soc. London, Vol. 12, p. 328, 1917; Thiele, Archiv fur Molluskenkunde, Vol. 56, p. 109, 19—; Wiss. Erg. Deutsch. Tiefsee-Exped., Vol. 17, p. 254 (page in separate 220), 1925. Not Milroniorpha A. Adams, Aim. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 322, April, 1865 = Antimilra Iredale (op. cil.), which is probably a section of Mitromorpha or a subgenus of Daphnella, type (by original designa- tion, Iredale) Pleuroloma segrota Reeve, Conch. Icon., Vol. 1, Pleurolojna, pi. 31, species 276, 1845, -}- Daph- nella crenulata Pease, Amer. Journ. Conch., Vol. 3, p. 221, pi. 15, fig. 20, 1868, from Paumotus. Type (by monotypy), Mitromorpha filosa Carpenter. Shell like that of the typical subgenus but broader, the shape becoming biconic ; sculptured with stronger spiral cords, which form, when axial riblets are also present, a reticulate pattern; posterior notch practically obsolete, denticulations sometimes present on the inside of the outer lip, but the lip not thickened. Geologic range: Upper Pliocene to Recent, California. Distribution: California, Lower California, Washington, also Alaska, according to Dall, and possibly also the western and southwestern Pacific. This biconic group of very small Turrlds was placed for many years in the Mitridce because of the mitriform appearance of the type species; but none of the species have col- umellar plications. Carpenter and Tryon classed them in the Turridce with Daphnella ; and lately Thiele has shown that M. filosa has a Mangelia radula. The writers have come to the same conclusion as Thiele from a study of the specific relationships, and because these relationships prove to be so close they are inclined to class Mitromorpha as a sub- genus of Mangelia. Thiele thought that Iredale's Antimitra, Lovellona, and Apaturris should have only the value of sections under Mitromorpha, but it is possible that the first of these at least might be better classed with Daphnella. The similarity between the species of Mitromorpha and the varieties of Mitrolumna olivoidea Cantraine, illustrated by Bucquoy, Dautzenberg, and Dollfus (Moll. Mar. Rous- sillon, Vol. 1, p. 121, pi. 15, figs. 23-39, 1883) is very striking, except that the latter have strong columellar plications and belong to the Mitridve. Mangelia (Mitromorpha) filosa (Carpenter) "? Daphnella" filosa Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 658 and note, 1864. Mitromorpha filosa Carpenter, Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 182, February or March, 1865, reprinted in Smithsonian Misc. Coll., No. 252, pp. 144, 284, (bottom pagination), 1872; Keep, West Coast Shells, p. 55, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, pi. 19, fig. 1, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 223, 1903; Dall, Bull. 112 U. S. Nat. Mus., p. 87, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 11, 1925; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 173, 1927. Daphnella (Mitromorpha) filosa Tryon, Man. Conch., Vol. 6, ]). 317, pi. 25, fig. 63, 1884. Volume I J PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 597 Shell small, biconic; whorls convex but overlapping so as to form a smoothly conic spire, sculp- tured with strong spiral cords only, about 22 on the body whorl, of which three or four show on the spire whorls; aperture more than half as long as the shell, elongate, lenticular, outer lip sculptured on the inside with about twelve small denticles, posterior notch obsolete, columella not defined from the general outline of the body whorl, anterior canal short, blimt, not defined. Dimensions: Altitude, 8 mm.; length of aperture, 5 mm.; diameter of body whorl, 3.5 mm. Type specimen: In the British Museum. Type locality: Santa Barbara, California. Pleistocene: Lower San Pedro of San Pedro, Los Angeles Co. (Arnold; T. S. Oldroyd); upper Pleistocene of San Quintin Bay, Lower California (Jordan). hiring: Monterey to the Gulf of California (Dall). This species is an extreme form, but the related species (gracilior and interfossa) con- nect it directly with the more typical species of Mangelia subgenus Beta; and others {aspera and rhyssa) point to a relationship with Agathotoma. M. gracilior is the closest, but it can be distinguished by its retention of the axial riblets on the earlier whorls. Mangelia (Mitromorpha) gracilior (Hemphill in Tryon) Plate 25, Figure 22 Daphnella aspera var. gracilior Hemphill, Tryon, Man. Conch., Vol. 6, p. .317, pi. 2.5, fig. 62, 1884. Mitromorpha intermedia Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 223, pi. 4, fig. 10, 1903. Mitromorpha filosa intermedia .\rnold, Berry, Nautilus, Vol. 22, p. 38, 1908. Mitromorpha gracilior Hemphill, Dall, Bull. 112 U. S. Nat. Mus., p. 87, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 174, 1927. Mitromorpha gracilior intermedia Arnold, Dall, Bull. 112 U. S. Nat. Mus., p. 87, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 174, 1927. Shell small, slender, biconic; whorls somewhat rounded, with impressed sutures, sculptured by rather distant spiral ridges, about twelve on the body whorl of which three or four show on the spire whorls, and by axial riblets which usually become obsolete on the body whorl; aperture elongate, lenticular, less than half the length of the shell, outer lip somewhat arcuate posteriorly, smooth in- teriorly, columella somewhat elongated, anterior canal not defined. Dimensions: Altitude, 9.5 mm.; length of aperture, 4.5 mm.; diameter of body whorl, 3.9 mm. Type specimens: Of gracilior, in the Oldroyd Collection at Stanford University; of intermedia, No. 162,557 in the U. S. National Museum. Type localities: Of gracilior, living, Monterey, California; of intermedia, lower San Pedro Pleistocene, of Deadman Island, San Pedro harbor, Los Angeles Co. U. Pliocene: Santa Barbara (Arnold; Berry). Pleistocene: Tj-pe locality of intermedia. Living: Forrester Island, Alaska, to San Diego (Dall), no other reference for the northern part of the range. This species is truly intermediate between filosa and aspera and interfossa. It is more slender than filosa, with a more elongate aperture and a smooth outer lip, and has weak axial sculpture. M. aspera has stronger axial sculpture forming a nodulous, reticulate pattern with the spirals. M. interfossa is similar to aspera but has more numerous ribs and spirals than aspera and more rounded whorls. It is interesting to note that Berry identified intermedia as living at Monterey. Mangelia (Mitromorpha) interfossa Carpenter Mangelia interfossa Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 628, 658, 1864; Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 29, 1865, these publications reprinted in Smithsonian Misc. Coll., No. 252, pp. 114, 144, 242 (bottom pagination), 1872. Not "Daphnella interfossa Carpenter," Tryon, Man. Conch., Vol. 6, p. 310, pi. 22, fig. 57, 1884, = M. variegata. 598 San Diego Society of Natural History [ Memoirs Mitromorpha filosa Carpenter var. barbarensis Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 20, pi. 57, fig. 1, 1907, figure reprinted in Bull. 321 U. S. Geol. Survey, pi. 11, fig. 1, 1907. Mangilia interfossa Carpenter, Dall, Bull. 112 U. S. Nat. Mus., p. 82, 1921; Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 85, 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 144, 1927. "Daphnellafuscoligata Dall," T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 10, 1925. Shell small, biconic ; whorls not very much rounded but with distinct sutures, sculptured with about fifteen spiral lines, of which four to six appear on the spire whorls, and with about an equal number of axial riblets that are hardly at all nodulous at the intersections; aperture equal to or a little less than half the length of the shell, elongate, lenticular, outer lip simple, posterior notch obso- lete, columella moderately long, anterior canal somewhat drawn out but not distmctly dcfuied. Dimensions: Altitude, 6 mm. ; length of aperture, 3 mm. ; diameter of body whorl, 2 mm. Type specimens: Of interfossa, in the British Museum ?; of barbarensis, No. 165,245 in the U. S. National Museum. Type localities : Of interfossa, Neah Bay, Washington ; of barbarensis, upper Pliocene of Bath-house Beach, Santa Barbara. Pliocene: Type locality of barbarensis. Pleistocene: Lower San Pedro of the Nob Hill cut, San Pedro, Los Angeles Co. (T. S. Oldroyd). Living: Vancouver Island, British Columbia, to Catalina Island, California (DaU). The species figured by Tryon is M. variegata, which cannot be what Carpenter de- scribed as interfossa because it has finer, very much more numerous spiral striations and more convex whorls than are called for by Carpenter in his description of interfossa. Furthermore, Tryon's figure shows the prominent color band of variegata, which Carpenter would surely have mentioned if it had occurred on his specimen of interfossa. M. interfossa is so very close to M. aspera that the distinctions must be looked upon as of doubtful value. The two species have not before been recognized as closely related, partly because of Tryon's misidentification and partly because the two have hitherto been classed in different families. M. interfossa is distinguished from aspera by its somewhat larger size, its more elongate shell, its less convex whorls, and' its more numerous, less nodulous axial riblets and spiral cords. Mangelia (Mitromorpha) aspera (Carpenter) "f Daphnella" aspera Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 658, 1864; Journ, de Conchyl., Vol. 12 (Ser. 3, Vol. 5), p. 146, 1865; these publications reprinted in Smithsonian Misc. Coll., No. 252, pp. 114, 314 (bottom pagination), 1872. Daphnella aspera Carpenter, Tryon, Man. Conch., Vol. 6, p. 317, pi. 25, fig. 61, 1884. ' Mitromorpha aspera Carpenter, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 208, pi. 19, fig. 3, 1892; Dall, Bull. 112 U. S. Nat. Mus., p. 87, 1921; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 174, 1927. Shell small, short, biovate; whorls somewhat roimded, sutures shallow, sculpture of about thir- teen narrow axial riblets crossed and nodulated by about ten similar spiral cords, of which only two or three show on the spire whorls; aperture a little less than half the length of the shell, lenticular, outer lip simple, not notched behind, columella not differentiated from the outline of the shell, blunt, anterior canal short, not defined. Dimensions: Altitude, 5.5 mm.; length of aperture, 2.5 mm.; diameter of body whorl, 2.3 mm. Type specimen : In the British Museum ( Jide Oldroyd) . Type locality: Monterey, California. U. Pleistocene: San Quintin Bay, Lower California (Jordan). hiving: Monterey to San Pedro (Dall). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 599 This species is intermediate between interfossa and crassaspera. The former has finer sculpture and a more drawn-out anterior canal; the latter has coarser sculpture and an aperture expanding anteriorly, with practically no canal. The latter has not generally been recognized as related because the species of this group have lately been so widely scattered among other genera. Mangelia (Mitromorpha) crassaspera, new name Vaphnella fuscoligata Dal!, Amer. Journ. Conch., Vol. 7, p. 100, 1871; Tryon, Man. Conch., Vol. G, p. 301, pi. 34, fig. 95, 1884; Dall, Bull. 112 U. S. Nat. Mus., p. 83, 1921; not of T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 10, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 1, p. 150, 1927; not Mangelia ? rigida, va.T. fuscoligata Carpenter, Proc. Zool. Soc. London, p. 163, 1856. Shell of medium size, spire moderately high ; whorls somewhat roimded, sutures shallow, sculp- ture of strong axial riblets, about twelve to a whorl, crossed liy equally strong spiral cords, six or seven on the body whorl, two of which show on the spire whorls, riblets nodulous at the intersections; aper- ture less than half as long as the shell, ovate, wider anteriorly, outer lip moderately curvmg, with a faint posterior notch close to the suture, columella hartlly differentiated from the general outline of the body whorl, not long, anterior canal short, shallow. Dimensions : Altitude, 8 mm. ; length of aperture, 3.5 mm. ; diameter of body whorl, 3.2 mm. Type specimen: In the U. S. National Museum. Type locality: Monterey, California. Living: Monterey to San Diego (Dall). It was hoped that this species would fall as a synonym of aspera so that the nomen- clatorial difficulties of handling it in a subgenus of Mangelia could be avoided ; but the specimens in the Oldroyd Collection at Stanford University are not conspecific, unless the variability is greater than the specimens mentioned give evidence of. It is to be noted, however, that they come from the same type locality and have nearly the same distribu- tion. M. crassaspera is distinguished from aspera by its somewhat larger size (with the same number of whorls), by its coarser sculpture, and by its differently shaped aperture. "Mangilia" muricidea Moody is quite similar in general appearance, but it has a longer columella and anterior canal, and it is probably the same as "Turris" kirkensis Clark, which is the young of Tritonalia lurida variety munda (Carpenter). M. crassaspera is closely related to M. rhyssa Dall, which is smaller and has a higher spire and shorter aper- ture. M. (Bela) interlirata Stearns is also very similar; but it is high spired and larger, and the ribs are higher than the spirals, as in typical Mangelia. There are really no gaps in these series of species suitable for drawing subgeneric divisions; but some of the extremes are distinct enough to warrant the few subgeneric groups here outlined. M. crassaspera bears a striking resemblance to Mangelia quadrillum (Dujardin) from the Miocene of France (figured by Cossmann, E,ss. Paleo. Comp., Vol. 2, pi. 7, fig. 14, 1896). Mangelia (Mitromorpha) rhyssa Dall Mangilia (Clalhromangilia) rhyssa Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 62, pi. 21, fig. 3, 1919. Mangilia rhyssa Dall, Bull. 112 U. S. Nat. Mus., p. 82, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 143, 1927. f Clalhromangilia rhyssa Dall, T. S. Oldroyd, Proc. U. S. Nat. Mu.s., Vol. 65, Art. 22, p. 10, 1925. Shell similar in sculpture to M . crassaspera, but with a taller, narrower spire and a short, narrow aperture, posteriorly rounded and anteriorly without a canal. Dimensions: Altitude, 7 mm. ; length of aperture, 2.5 mm. ; diameter of body whorl, 2.5 mm. 600 San Diego Society of Natural History [ Memoirs Type specimen: No. 55,479 in the U. S. National Museum. Type Jocality: Gulf of California (I. S. Oldroyd gives San Diego, but Dall names only the Gulf of California, Stearns Collection, in the original). Pleistocene: Lower San Pedro of Nob Hill cut, San Pedro, Los Angeles Co. (T. S. Oldroyd). Living: San Diego to the Gulf of California. This peculiar little species looks more like the type of Clathromangelia, which is prob- ably a synonym of Clathurella, than a Mitromorpha; but its specific relationships seem to be with the latter, and it lacks the deep notch and the thickened, denticulate outer lip of the former. Clathurella is more distantly related through Agathatoma. Besides the species here considered, the writers are inclined to class " Clathrodrillia" limans Dall, 1919, also in the subgenus Mitromorpha, although it is possible that this pe- culiar little species may belong to Anachis, subgenus Chauvetia, in the Pyrenidce. Subgenus ZETEKIA Dall, 1918 Zetekia Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 320, 1918. Type (by monotypy), Zetekia denticulata Dall, briefly diagnosed, 1918, described and figured, Proc. U. S. Nat. Mus., Vol. 56, p. 73, pi. 1, fig. 1, 1919, living, Panama. Shell short and conical like that of Mitromorpha, with axial and spiral cords meeting in little beaded knobs ; both lips denticulate, anterior canal short, undefined, somewhat notched, otherwise as in Agathatoma. Distribution: Panama. This subgenus is intermediate between Mitromorpha and Agathatoma. Perhaps "Philbertia" telamon Dall, 1919, from the Gulf of California, should be classed here. Subgenus AGATHOTOMA Cossmann, 1889 Ditoma Bellardi, Mem. R. Accad. Sci., Torino, Ser. 2, Vol. 29, p. 295, 1877; Cossmann, Ess. PaMo. Comp., Vol. 2, p. 125, 1896. Agalholoma Cossmann, Revue Critique de Pal6ozool., Vol. 3, p. 1, 1899, new name for Ditoma BeUardi, 1875, nan Illiger, 1807; Ess. Palfo. Comp., Vol. 3, p. 192, 1899. "Cytharella Monterosato," DaU, Proc. U. S. Nat. Mus., Vol. 54, pp. 320, 325, 1918, type Pleurotoma bertrandi Pay- raudeau, not in Monterosato's original list; so used by Dall and other authors after 1918. "Philbertia Monterosato," DaU, in part. Type (by monotypy), Mangelia angusta Jan, Miocene and Pliocene of Europe, de- scribed by Bellardi {loc. cit.), figured by Cossmann, Ess. Paleo. Comp., Vol. 2, pi. 7, figs. 29, 30, 1896. Shell like that of the typical subgenus but with a deeper posterior notch at all stages of growth, and often a somewhat thickened outer lip, the columella and anterior canal comparatively short and blunt; sculpture of wave-like axial folds crossed by spiral grooves. Geologic range: Eocene to Recent (Cossmann, as Mangelia). Distribution: Tropical, subtropical, and occasionally temperate waters of all seas. This subgenus appears quite different from the typical Mangelia, especially in illus- trations; but an examination of specimens shows that the differences in aspect are due to a very slight variation in characters. The shells are for the most part thin except at the varices, which, as in the typical subgenus, serve to strengthen the shell, and when Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 601 small in number meet end to end to form continuous ridges up the spire. The ridges are stronger and more wave-like than in the typical subgenus and are crossed by fewer, strong- er spiral grooves. The principal differences are in the depth of the notch and the length of the anterior canal ; but these differences are a matter of degree only and all intergrada- tions occur. Bela is more distinct than typical Mangelia, having a weaker notch and smaller axial ribs; but intergradations even between Bela and Agalhotoma occur, and such species as intcrlirata Stearns might be placed in the section MangilieUa, intermediate be- tween the two subgenera. The subgenus Pseudoraphitoma is similar to Agathotoma, but has a higher spire, a shorter aperture, and a denticulate outer lip. The species of this subgenus vary considerably in form : those with thinner shells and less thickened outer lip approach M. merita of the typical subgenus; those with higher spires, few longitudinal ridges continuous up the spire crossed by fine spiral grooves ap- proach Pseudoraphitoma; those with coarser spirals resemble somewhat Clathurella, but do not have the same kind of posterior notch, nor are they apt to have denticles on the inside of the outer lip as in Clathurella. The typical species of Agathotoma are those that approach Pseudoraphitoma. They have a strongly thickened outer lip, into which the posterior notch is deeply sunken, part of the lip often forming a swollen collar around the notch and joining onto the upper part of the otherwise not thickened inner lip. Also, there may be a single, more or less prominent fold or denticle on the inside of the outer lip immediately below the notch. These features are shown in the rib-stage of typical Man- gelia, though less strongly. So far no true species of Agathotoma have been reported as fossil in California or Lower California, but there are a number of living species that might be expected to appear in the fossil state at any time. Among these the writers would include the fol- lowing: "Cytharella" niobe Dall, 1919. "Philherlia" telamon Dall, 1919. "Philhertia" hilaira Dall, 1919. "Philherlia" dictynna Dall, 1919. " Philberlia" scammojn Dall, 1919. "Philherlia" segialea Dall, 1919. "Philherlia" cloHs Dall, 1919. "Philherlia" sethra Dall, 1919. "Cytharella" phsthusa Dall, 1919. "Cylharella" (Agathotoma) penelope Dall, 1919. "Cytharella" louisa Dall, 1919. "Cylharella" (Agalhotoma) eamerina Dall, 1919. "Cytharella" subdiaphana (Carpenter), Dall, 1919. "Cylharella" (Agatholoma) euryclea Dall, 1919. "Cytharella" quadriseriata Dall, 1919. "Cylharella" (Agatholoma) pyrrhula Dall, 1919. "Cytharella" hippolita Dall, 1919. "Cytharella" (Agatholoma) phryne Dall, 1919. "Cytharella" aculea Dall, 1919. "Cythara" vicloriana Dall, 1897, (figure reproduced by "? Hsedropleura" melila Dall, 1919. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., "Philhertia" helena Dall, 1919. Vol. 4, p. 86, pi. 45, fig. 14, 1924). These species are arranged roughly in the order of similarity. There are probably many synonyms among them, for Dall took practically no account of variation, and many of the older names of Hinds, Reeve, Carpenter, Adams, and others are yet to be con- sidered. Subgenus PSEUDORAPHITOMA Boettger, 1895 Pseudoraphitoma Boettger, Deutsche Malakozoologische Gesellschaft (Frankfurt-am-Main), Nachrichtsblatt, p. 56, 1895. Type (by monotypy), Mangilia fairbanki Nevill, living, Bombay, figured by Tryon, Man. Conch., Vol. 6, p.'270, pi. 22, fig. 48, 1884. Shell like that of Agathotoma but with a high spire and denticles on the inside of the outer lip. This subgenu.s has not yet been recognized along the Pacific coast of North America; but several species of Agathotoma, such as hippolita, etc., approach it. 602 San Diego Society of Natural History [Memoirs Genus CYTHARA Schumacher, 1817 Cythara Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 245, 1817; Dall, Proc. U. S. Nat. Mus., Vol. 54, pp. 319, 325, 1918. Mangelia Leach, Reeve, Conch. Icon., Vol. 3, 8 pis., 1846, not Mangelia Risso, 1826. Eucithara Fischer, Man. Conchyl., p. 593, 1883, new genus proposed with Cythara Schumacher, 1817, non Klein, 1753, in s5aionymy and M. stromboides Reeve cited as an example; Cossmann, Ess. Paleo. Comp., Vol. 2, p. 120, 1896, type cited Cancellaria citharclla Lamarck; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 326, 1918; Hedley, Rec. Australian Mus., Vol. 13, p. 260, 1922; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 168, 1928. Type (by monotypy), Cythara striata Schumacher, loc. cit., 1817, based on Chemnitz, Neues Syst. Conch. Cab., Vol. 4, p. 166, pi. 142, fig. 1330 only, 1780, = Pterygia subter- ranea Bolten, Mus. Bolt., p. 51, 1798, + Cancellaria citharella Lamarck, Hist. Nat. Anim. s. Vert., Vol. 7, p. 115, 1822; Desh. and M. Edw. Ed., Vol. 9, p. 407, 1843; discussed and illustrated by Reeve, Conch. Icon., Vol. 3, Mangelia, introduction to the genus, and pi. 1, species 5, 1846; figure repeated by Tryon, Man. Conch., Vol. 6, p. 257, pi. 24, fig. 13, 1884. Shell of medium size, spire usually rather low; whorls angulated near the top, sculptured with a moderate number of long, curving, rounded axial ribs, crossed by much less prominent spiral stria- tions or color bands; aperture very long and narrow, averaging about three-fifths as long as the shell, usually in mature shells bordered on both sides with a row of denticles, outer lip sometimes flaring posteriorly and bent inward just below the flare as in Pijrene, inner lip, columella, and outline of the body whorl passing downward nearly straight, like an inverted elongate cone, anterior canal a somewhat irregular prolongation of the aperture, notched behind. Distribution: Southwestern Pacific and Indian Ocean. This genus offers several very perplexing nomenclatorial problems besides the zoological problem of determining the identity of the type species. Recently Hedley and Woodring have decided to abandon the name entirely; but the writers feel that this course is not necessary, and that if it were, the name Eucithara, used by Hedley and Woodring, is not available as a substitute. The aim of the International Code of Zoological Nomenclature is to stabilize the use of names by making as few changes as possible. Therefore, when a name is entitled to priority and has been in current use for some time, the burden of the proof lies upon those who wish to change the name; and before they have a right to change it or before they should be followed in doing so, they must offer proof that the old name has been im- properly applied. It does not seem sufficient to the writers for them to show that it might have been improperly applied. Thus the name Cythara, which is the oldest name that has been applied to this group of species, has been in use for many years by workers in all parts of the world. The genus was based on a description by Schumacher and a figure in Chemnitz, neither of which is incompatible with the generally accepted usage, though it must be admitted that neither is very satisfactory. The fact that Chemnitz figured his specimen along with young Strombi is not of importance, for Schumacher specifically denies any relation with the other figures. Reeve carefully explains Lamarck's error in referring the species to Can- cellaria. The reference of the species by older writers to various other genera casts doubt upon its identity, but does not prove anything in the face of Reeve's deliberate and fully explained identification of the species as a member of the group we are now considering. Furthermore, even if Reeve should have mistaken the species (the species illustrated by Reeve lacks the apertural denticulations specified by Schumacher and may be immature), if the species can be identified merely as an unknown or not yet determined member of the group, it is sufficient to establish the use of the name. Thus, the present writers have come to the conclusion that sufficient proof has not yet been presented to overthrow the Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 603 accepted usage of Cyihara, which of course is not preoccupied by the pre-Linnsean Cithara Klein. If later the specimens of Chemnitz are found and consulted, all doubt can then be removed about the proper application of the name. If it should be discovered that the species belongs to some other genus, it will be time enough then to propose a substitute, whereas if the general usage of the term has been correct, a double shifting of names will have been avoided. The availability of the name Eucithara Fischer as a substitute is seriously open to question. Many nomenclature specialists would say that as Eucithara was proposed as a substitute for Cythara on the mistaken contention that the name was preoccupied, the name must be an exact synonym, having for its type the same species as Cythara. How- ever, the present writers believe that both the species originally cited by the author of the original genus (the genus that was listed in the synonymy of the new genus) and the species given by the author of the new genus at the time the name was proposed should be available for type, and that the type should be determined according to the ordinary processes of type fixing. Fischer named no type, and as there is no tautonymy, the type must be fixed by subsequent designation. Cossmann, 1S96, is the first to designate a type, naming Cancellaria citharella Lamarck. It might be contended that this species was not present by name in either list and that therefore the designation is invalid ; and it is true that the citing of even a generally accepted synonym of a species cannot be accepted as a valid designation, if the synonymy is a matter of opinion, for there would be danger that at some time the two names might be shown to apply to different species. In this particu- lar case, however, the two names are in a technical sense exact synonyms, being based on the same figure and therefore having the same type specimen, so there never could be any doubt about the species citharella being present in Schumacher's original list. The writers beheve, therefore, that in such cases of exact synonyms it would be an absurd technicality to declare the citation invahd; and they conclude that although Fischer's example was originally available for type, it was no longer so after Cossmann's designation in 1896. Thus, Eucithara is to be regarded as an exact synonym of Cythara. Cythara is distinguished from the other small Turrids by its short spire, its elongately conical body whorl, and its long, narrow aperture with denticulate margins. Conopleura Hinds^ is merely an extreme form of the same genus with sharper shoulders and a some- what deeper posterior notch, recalling Pleurotomoides. Cytharopsis A. Adams'- may be an elongate form of this genus with stronger spiral sculpture. If the name Cythara is un- acceptable to nomenclature specialists, these two names should be considered before an- other substitute is proposed. The genus Cythara has been discussed here, although it appears to be entirely foreign to North America, partly because it was hoped that such a discussion might help to clarify some of the current nomenclatorial problems, and partly because it was considered important to show what has become of one of the oldest names that has been applied to California Turrids. The reference by Gabb, Dall, Pilsbry,'' and others of several species in the Tertiary of Florida and the West Indies to this genus is somewhat questionable, but it is still not unlikely that the genus might be found, along with other Oriental genera, in the older Tertiary of California. 1 Conopleura Hinds, Zool. Voy. Sulphur. Moll., p. 24, 1844, type (by monotypy) C. striata Hinds described, loc. cil., and figured pi. 7, figs. 22, 23, not striata Schumacher: = Pleurotoma partita Reeve, Conch. Icon.. Vol. 1. Pleurotoma, pi. 36. species 330, 1846, figures reproduced by Tryon, Man. Conch., Vol. 6, p. 211, pi. 8, figs. 6, 7, 1884. 2 Cytharopsis A. Adams, Ann. and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 323, 1865, type (by monotypy ?) Mangelia (.Cytharopsis) cancellata .\. Adams, described loc. cit.. but not figured; described by Tryon. Man. Conch., Vol. 6, p. 274, 1884. 3 Pilsbry, Proc. Acad, Nat. Sci., Phila., Vol. 73, pp. 322-23, 1922. 604 San Diego Society of Natural History [ Memoirs Genus CLATHXJRELLA Carpenter, 1857 ClatJmrella Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 399, 1857, new genus proposed with Defrancia Millet not Bronn in the synonymy and with Clamtula rava Hinds and Clathurella aurea, new species, as ex- amples for "A convenient group of the Mangelia tribe; the name Defrancia, previously in use, being pre- occupied;" Cossmann, Ess. Pal(5o. Comp., Vol. 2, p. 121, 1896, type cited Clavatula ram Hinds. Glyphostoma Gabb, Proc. Acad. Nat. Sci., Phila., p. 270, 1873, type (by monotypy) Glyphostoma dentijerum Gabb, described, loc. cit., and illustrated, pi. 9, fig. 4, also described and figured by Cossmann in the Ess. Pal^o. Comp., Vol. 2, p. 124, text figure 29, 1896, and in the Journ. de Conchyl., Vol. 11, p. 31, pi. 2, figs. 15-17, with variety marlinicensis Cossmann, figs. 18-20, 1913, and by Pilsbry, Proc. Acad. Nat. Sci., Phila., Vol. 73, p. 324, pi. 17, fig. 15, 1922, Miocene, West Indies; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 191, 1928. ? Clathrotnangelia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 131, 1884, tj^pe (by monotypy) Pleurotoma granvm Philippi, Enum. Moll. Siciliae, Vol. 2, p. 170, 1844, -f P. rude Philippi, Vol. 1, p. 199, pi. 11, fig. 16, 1836, (not P. rude Broderip), figure reproduced by Tryon, Man. Conch., Vol. 6, p. 276, pi. 33, fig. 68, 1884, Recent, Mediterranean. Lienardia Jou.sseaume, Bull. Soc. Zool. France, Vol. S, p. xl, 1884, Vol. 9, p. 184, 1884, type (by original designation) Clavatula rubida Hinds, Proc. Zool. Soc. London, p. 40, 1834, Zool. Voy. Sulphur, Moll., p. 18, pi. 6, fig. 6, 1844, also illustrated by Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 25, species 220, 1845, and by Tryon, Man. Conch., Vol. 6, p. 271, pi. 15, fig. 34 (coloring not typical), pi. 19, fig. 51, 1884, Recent, New Guinea; Hedley, Rec. Australian Mus., Vol. 13, p. 285, 1922. Hemipleurotoma Boettger, Deutsche Malakozoologische GeseUschaft (Frankfurt-am-Main), Nachrichtsblatt, Jahr. 27, p. 52, 1895, type (by original designation) Pleurotoma (Defrancia) malleti Recluz, Journal de Conchyl., Vol. 3, p. 254, pi. 10, fig! 2, 1852, also figured by Tryon, Man. Conch., Vol. 6, p. 297, pi. 20, figs. 96, 100, 1884, Recent, western Pacific; Hedley, Rec. Australian Mus., Vol. 13, p. 294, 1922. Not Clathurella Dall, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 259, 1908; etc. . Type (by subsequent designation, Cossmann, 1896), Clavatula rava Hinds, Zool. Voy. Sulphur, Moll., p. 17, pi. 5, fig. 18, 1844, also illustrated by Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 28, species 250, 1845, and by Tryon, Man. Conch., Vol. 6, p. 296, pi. 18, fig. 42, 1884, Recent, Philippines. Shell of medium or small size ; protoconch consisting of two or three small bulbous whorls, smooth except for an ol)tuse angle which appears on the second whorl of species that have markedly angulated whorls ; adult whorls usually angulated near the top, in which case the area of the anal f asciole above is concave, sculptiu'ed only with strongly curvmg growth lines or fine spiral Imes or both, sculpture on the mam jjart of tlie whorl of broad rounding ribs crossed by spiral cords of varymg strength; aperture varying from two to three-fifths the length of the shell, elongate-ovate, prolonged at both ends by similar, deep, notched canals, outer lip of adult shell thickened and provided with a number of rather prominent denticles, posterior notch heavily armored on both sides, inner lip also usually denticulate, with a callus remforcement at the top, columella rather long, nearly straight, anterior canal short but usually well defhied, notched and flaring at the end; animal inoperculate. Geologic range: Eocene (of Australia, ^de Cossmann), lower Miocene to Recent in the West Indian region (Woodring); Pliocene to Recent, California. Distribution: Tropical and warm temperate waters of all oceans. Here again we have the nomenclatorial question of whether a species included in a genus by the original author of the genus at the time and place in which he proposed the generic name can be available for type, even though the synonymy of the new generic name may include an older, preoccupied name, in the original description of which that species was not included. The present writers think it can, and therefore accept Coss- mann's designation of the type of this genus. They have discussed this nomenclatorial point under the genera Lora, Raphitovia, and Cythara. A number of writers recently have been inclined to recognize most of the names here listed in the synonymy as distinct genera along with a number more of their own propos- ing. Time has not allowed a thorough investigation of the later names, but the present writers are convinced that most of them are based on unessential differences and that the nomenclatorial extravagance tends to obscure the natural facts without increasing the Volume I ] PLIOCENE AND PLEISTOCENE IVIOLLUSCA OF CALIFORNIA 605 accuracy of the classification. For instance, Lienardia is nearly always separated from GlypJwstoma, and yet Woodring in figuring species of Glyphostoma from the Miocene of the West Indies in the district where Gabb found the type of Glyphostoma figures one, G. guppyi, which is barely distinguishable specifically from the type of Lienardia. Not only that, but there are typical species of Glyphostoma with broad fascioles even in the western Pacific. Usually the protoconchs are relied upon as a last resort to separate these sup- posed genera on the theory that diverse protoconchs indicate different ancestry. How- ever, as explained in the introduction to the TurridcB, too little is yet known about the sig- nificance of protoconchs to make them reliable as criteria for distinguishing genera. Two interesting observations were made on the protoconchs of this genus. One was that among the species that had strongly angulated adult whorls the angulation of the protoconch whorls was most conspicuous, as if the latter were due entirely to an accelera- tion of the time in the development of the individual at which the angulated character first appears. The other was that the blunt appearance of the protoconchs of the western Pacific species is usually due to wear. Of seven specimens of C. rubida (Hinds) in the Old- royd Collection at Stanford University, only one small one had a sharp apex as in Reeve's figure. On all the others the protoconchs, and in some cases one of the mature whorls as well, were smoothly ground down to a blunt point as if they had always been that way. Hedley mentions that the protoconch of Etrema, one of his new names for this genus, is essentially the same as that of Glyphostoma. Clathurella varies considerably in size, in the relative height of the spire, the relative strength of the spiral and axial sculpture, the width of the anal fasciole, the sharpness of the angulation of the whorls, and the amount of armature of the lips and of the posterior notch. It grades into the coarsely sculptured species of MangeUa and into Raphitoma, but it can usually be distinguished by its deep, heavily armored posterior notch, its denticu- late lips, its concave anal fasciole, and its short, distinctly defined anterior canal. Young specimens do not have the denticulated lips, and some species may never develop them, but usually such species can be recognized by the other characters. This genus probably grades in the other direction into Cythara, but the latter can usually be distinguished by its lower spire, etc. It also approaches very closely small species of Clavus of the sub- genera Clathrodrillia, Cymatosyrinx, Crassispira, etc. ; but the latter do not have denticu- late lips, do have opercula, and are normally considerably larger. A large number of species of this genus that have been described from southern waters by Hinds, Reeve, Adams, Carpenter, and others the WTiters have not had time to look up. Probably most of Ball's recently named species will fall into the synonymy of the older names. The following notes do not include all of the Uving species : Clathurella Candida (Hinds) Clavatula Candida Hinds, Proc. Zool. Soc. London, p. 42, 1843; Zool. Voy. Sulphur, Moll., p. 20, pi. 6, fig. 18, 1844. PUuTotoma Candida Hinds, Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 25, species 221, 1845. MangiUa Candida Hinds, Tryon, Man. Conch., Vol. 6, p. 273, pi. 15, fig. 41, 1884. Glyphostoma partefilosa Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 53, pi. 17, fig. 4, 1919. Shell broad, with rounded ribs, striations only on the columella; aperture and notch heavily armored. Liriiig: Gulf of California to the Magnetic Island, west coast of Veragua. Dall, as is so often the case, makes no comparisons, and yet the synonymy is quite evident. 606 San Diego Society of Natural History [ Memoirs Clathurella conradiana Gabb Plate 26, Figure 11 Clathurella conradiana Gabb, Geol. Surv. Calif., Pala?o., Vol. 2, p. 7, pi. 1, fig. 12, 1866, p. 73, 1868-9; Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 297, 1874; Cooper, 7th Ann. Rept. Calif. St. Mining Bureau, p. 23.5, 18S8; Arnold, Bull. 321 U. S. Geol. Survey, p. 32, pi. 11, fig. 9, 1907. Mangilia (Clathurella) conradiana Gabb, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 210, 1903; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 44, 1916. Glyphostonw cymodoce Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 54, pi. 17, fig. 6, 1919; Bull. 112 U. S. Nat. Mus., p. 79, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 127, 1927. Glyphostoma conradiana Gabb, Dall, Bull. 112 U. S. Nat. Mus., p. 79, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 126, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Shell of moderate .size, with a fairly high spire; whorls angulated near the top, concave above where they are sculptured with six or seven fine spiral lines and strongly curvmg growth lines, convex below and sculptured with 10 to 12 rounded axial ribs crossed by spiral cords, about 14 of the latter on the body whorl, three or four showing on the sjjire whorls, with sometimes a few lesser inter- calaries ; aperture about two-fifths the length of the shell, ovate, prolonged at both ends by very simi- lar canals, outer lip of the adult somewhat thickened, denticulate within, posterior notch deep, inner lip incrusted, only moderately armed at the top, columella fairly long, straight, anterior canal defined, short, notched behmd. Dimensions: Altitude, 11 mm.; length of aperture, 5 mm.; diameter of body whorl, 4 mm. Type specimens: Of conradiana, at the University of California; of cymodoce, No. 150,569 in the U. S. National Museum. Type localities: Of conradiana, "Post-Pliocene of Santa Barbara;" of cymodoce, living, Santa Barbara. M. Pliocene: San Diego weU (Dall, 1874). U. Pliocene: Santa Barbara (Gabb; Arnold); Fourth and Broadway, Los Angeles (Moody); upper Pico of Ventura Co. (Waterfall) ; loc. 218 S. D. S. N. H., Sulphur Canyon east of South Mountain, Ventura Co., one specimen (H. R. G.). Pleistocene: "Phocene" and lower San Pedro series at Deadman Island, San Pedro harbor, and San Pedro, Los Angeles Co. (Arnold). Ldiring: Monterey to San Pedro, and possibly south to Ecuador. A certain amount of variability is to be expected in this species as in others, but the writers have not had sufficient material to determine its extent. The synonymy seems quite plain in the case of cymodoce, and the synonymy of other described forms seems quite probable. Glyphostoma adana Dall, 1919, from Lower California, and G. sirena Dall, 1919, from the Galapagos, are very close to conradiana; and "Mangilia" laodice Dall, 1919, is probably an immature Clathurella, perhaps also belonging to this species. G. adria Dall, 1919, from Lower California, has a more heavily armed lip, though the notch does not protrude sideways as much as that of C. rava (Hinds). C. affinis Dall' is a form ranging from San Miguel Island, California, to San Martin Island, Lower California, perhaps a variety of this species with stronger, more rounded axial ribs. The specimen here figured has something of this character, and there is one specimen of this form in the Oldroyd Collection at Stanford University labeled Clathurella canfieldi; but the specimens labeled Clathurella affinis are all canfieldi. C. canfieldi has shorter, broader whorls and typically weaker sculpture, but many specimens have stronger sculpture than the type and some have been identified as conradiana by Arnold, T. S. Oldroyd, and others. C. canfieldi may ' Clathurella affinis Dall, Amer. Journ. Conch., Vol. 7, p. 102, 1871; Proc. Calif. Acad. Sci., Vol. 5, p. 62, pi. 2, fig. 7. 1873; Baker, Nautilus, Vol. 16, p. 41, 1902. Philbertia affinis Dall, Bull. 112 U. S. Nat. Mus., p. 79, 1921; Oldroyd, St.mford T'niv. Publ. Geol., Vol. 2, Pt. 1, p. 12,8. 1927. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 607 also be a variety of conradiana. C. thalassoma (Dall),' from the Gulf of California, is a large species with more uniform, clathrate sculpture recalling somewhat C. dentifera (Gabb) not (Hinds), = f martinicensis Cossmann, from the Atlantic Miocene, and is probably a distinct species. Ball's "Mangilia^' philodice, said to range from Point Ano Nuevo, middle California, to the Coronado Islands off San Diego, looks very much like the yoiuig of thalassoma with the nucleus eroded. Clathurella canfieldi Dall ClalhureUn canfieldi Dall, Amer. Journ. Conch., Vol. 7, p. 101, pi. 15, fig. 9, 1S71. Philherlia canfieldi Dall, Bull, 112 U. S. Nat. Mus., p. 79, 1921; T. S. Oklroycl, Proc. IT. S. Nat. Mus., Vol. 65, Art. 22, p. 10 in part ?, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 1, p. 128, 1927. :' "Glyphostoma conradiana Gabb," T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 10, 1925. Shell much like that of conradiana, but with a shorter spire, the angulation higher on the whorls with onh' a narrow shelf above and the sides of the whorls almost vertical below, sculpture typicallj' weaker and smoother, but grading into forms very much as in conradiana; aperture broader, but with similar small denticles on the outer lip, present only on fully mature specimens or at certain growth stages, and a similar, weakly armored notch. Dimensions: Altitude, 8 mm.; length of aperture, 4.2 mm.; diameter of body whorl, 3.5 mm. Type specimen : In the U. S. National Museum. Type locality: Living, Monterey. Pleistocene: Lower San Pedro of San Pedro and vicinity, Los Angeles Co. (T. S. Oldroyd; Arnold; etc.). LAving: Crescent City, northern California, to Laguna Beach, a short distance south of Los Angeles. This species, although typically quite different, seems to intergrade with conradiana, and better material may show that the differences are of no more than varietal signifi- cance. As is nearly always the case when fine distinctions between species are described indefinitely or not described at all, each form has been identified by one or two authors (in this instance probably including Dall himself) under the name of the other; and in- stead of producing accuracy the fine distinction merely produces complexity. There is an older name that has been overlooked for many years, but which may, when the type is illustrated and more fully described, turn out to be the proper name for this species, — Mangelia hamata Carpenter.^ Dall states that the type of Carpenter's species looks like a fossil and may have come from the "Pleistocene" of Santa Barbara where Col. Jewett also collected, instead of from Panama where Carpenter reports that Jewett collected it. The rather deep anal sulcus and thickened lip, with the dimensions given by Carpenter, suggest that the species may belong here. Nevertheless, without an illustration it is impossible to be sure that it is not allied to Mangelia merita or some other group. It is regrettable that Dall did not figure the type (No. 15,951 in the U. S. National Museum) when he had it before him. Clathurella crystaUina Gabb Clalhnrella crysiallina Gabb, Proc. Calif. Acad. Sci., Vol. 3, p. 184, 1865. Clathurella loicei Dall, Proc. Biol. Soc. Wash., Vol. 16, p. 172, 190.3 (fide Dall). Philherlia crystaUina Gabb, Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 62, pi. 13, fig. 1, 1919; Bull. 112, U. S. Nat. Mus., p. 79, pi. 6, fig. 4, 1921 ; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 129, pi. 3, fig. 5, 1927. ' Glyphostoma thalassoma Dall, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 2S0, 1908; Proc. U. S. Nat. Mus.. Vol. 56, p. 32. pi. 17, fig. 2, 1919. f Mangilia philodiceDM. Proc. U. S. Nat. Mus., Vol. ,56, p. 66, pi. 22, fig. 7. 1919; Bull. 112 U. S. Nat. Mus., p. 81, 1921; Oldroyd, Stan- ford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 139, 1927. 2 Mangelia hamata Carpenter, Ann. and Mag. Nat. Hist.. Ser. 3, Vol. 15, p. 399, May, 1865, reprinted in Smithsonian Misc. Coll., No. 252, p. 293 (bottom pagination), 1872. Mangilia hamata Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 71. 1919. 608 San Diego Society of Natural History [ Memoirs Shell somewhat like the last but with a broader, more sloping area above the angle and a few sharper, more prominent spiral keels on and below the angle. Type specimens: Of crystalUna, at the University of California (?); of lowei, No. 109,305 in the U. S. National Museum. Type locality: Of both, 40 fathoms off Catalina Island. Known only from the type locality. This species was called Philbertia by Dall because the specimens so far found have not had denticles on the outer lip; but it is quite clearly a Clathurella, perhaps immature. Clathurella trichodes (Dall) Pleurotoma hirsuium de Folin, Les MelcSagrinicoles, p. 59, pi. 5, fig. 16, 1867, not Pleiirotoma hirsula Bellardi, 1848. Philbertia trichodes Dall, new name for Pleurotoma hirsittum de Folin, Proc. U. S. Nat. Mus., Vol. 56, p. 62, pi. 19, fig. 3, 1919. Shell very small ; whorls five, of which the first is smooth, others sculptured with a few strong, tlistant cords both axially and spirally, though sometimes the shell thin and nearly smooth ; aperture about half the length of the shell, with a very deep posterior notch, outer lip Avith a few coarse den- ticles, columella nearly straight, not encrusted at the top, anterior canal short, deep. Dimensions : Altitude, 4 mm. ; length of aperture, 1 .9 mm. ; diameter of body whorl, 2 mm. Type locality: Panama Bay {fide Dall). Distribution: Panama to the Gulf of California (Oldroyd Collection at Stanford University). This interesting little species is included to call attention to the change of name and to record its presence in the Gulf of California. It may be related to Nannodiella. Subgenus NANNODIELLA Dall, 1919 Nannodiella Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 329, type (by monotypy) N. nana Dall, nude name, 1918; Vol. 56, p. 59, 1919; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 194, 1928. Type (by original designation), Philbertia (Nannodiella) nana Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 59, pi. 20, fig. 7, 1919. Shell like that of Clathurella but much smaller, the posterior notch armored and projecting like a spout, but the lips not denticulate. Geologic range: Miocene to Recent, West Indies (Woodring). Distribution: Lower California and the Gulf of California; West Indies and Florida. Nannodiella is a dwarf group of Clathurella, being like the young of typical Clathurella, but with a mature notch. Genus RAPHITOMA BeUardi, 1848 Defranda Millet, M^m. de la Soc. Linn, de Paris, p. 437, 1826-1827, in part, not the type; not Defranda Bronn, 1825, genus of Bryozoa. Pleurotomoides Bronn, Ital. Tert.-Geb., p. 47, 1831, in part, not the type cited by Dall, 1918 (see heading for Pleiiro- iomoides) ; Dautzenberg and Fischer, Travaux de la Station Biologique de Roscoff, Fascicule 3, p. 32, 1925, type cited Miirex reticulalus Renier. Raphitoma BeUardi, Accad. delle Scienze di Torino, Memorie, Ser. 2, Vol. 9, p. 613, 1848, first species Pleurotoma hislrix Jan followed by many others; Monterosato, Bolletino della Societa Malacologica Italiana (Pisa), Vol. 1, p. 73, 1875, type cited Pleurotoma histrix Jan; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 179, 1928. Clathurella Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 399, 1857, in part, not the type cited by Coss- mann, 1896 (see heading for Clathurella) ■,'Da\\, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 259, 1908. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 609 Homotoma Bellardi, Bolletino della Societa Malacologica Italiana (Pisa), Vol. 1, p. 22, 1875, species included in the original list, Homotoma reticulata (Renier) and Homotoma semicostata Bellardi; Woodring, Carnegie Inst. Wash., Publ. No. 38.5, p. 188, 1928, no type has been selected from these two species; not Homotoma Guerin- M^ncville, 1829. Bellardia Bucquoj', Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, p. 88, 1883, type (by monotypy) Murex gracilis Montagu, living Great Britain, described and figured in nearly all the important works dealing with Turridse; not Bellardia Mayer, 1870, nor Robineau-Desvoidy, 1S63. Bellardiella Fischer, Man. Conchyl., p. 594, December, 1883, new name for Bellardia Bucquoy, Dautzenberg, and Doll- fus, not Mayer, 1870; not Bellardiella Tapp. Canefri, July. 1883. Cordieria Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 131, 1884, type (by virtual tautonymy) Pleurotoma cor- dieri Payraudeau, a synonym or variety of Murex reticulatus Renier and Murex purpureus Montagu; not Cordieria Rouault, 1848. Philbertia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 132, 1884, type (by virtual tautonymy and subsequent designation) Pleurotoma hicolor Risso, of which Pleurotoma philberti Michaud is cited by Monterosato in the synonymy; Dall, Proc. U. S. Nat. Mus., Vol. 54, pp. 321, 329, 1918, type cited, Pleurotoma bicolor Ri.sso + philberti Michaud + purpurea (Montagu) Bucquoy, Dautzenberg, and Dollfus var. bicolor. Cirillia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 133, 1884, type (by virtual tautonymy and subsequent designation) Murex linearis Montagu, in the synonymy of which Monterosato cites: "= P. C (O. G. Costa) Sc. per Ciriili, dedicata a Cirillo;" Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 323, 1918, type cited. Leufroyia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 134, 1884, type (by virtual tautonymy and subsequent designation) Pleurotoma leufroyi Michaud; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 328, 1918, type cited. Comarmondia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 135, 1884, new name for Bellardia and Bellardiella, preoccupied. Peratotoma Harris and Burrows, Eoc. Olig. Beds Paris Basin, \>. 113, 1891, new name for Homotoma Bellardi, pro- occupied. Psexidodaphnella Boettger, Deutsche Malakozoologische Gesellschaft (Frankfurt-am-Main), Nachrichsblatt, p. 58, 1895; Dall, Proc. U. S. Nat. Mus., p. 330, 1918, type cited Pleurotoma philippinensis Reeve. ? Olitoma Jousseaume, Le Naturaliste, Vol. 26, p. 106, May 1, 1898, type (by virtual tautonymy) Otitoma ottitoma Jousseaume, described loe. cit., but never figured; Iredale, Proc. Malac. Soc. London, Vol. 12, p. 327, 1917. Clalhurina Melvill, Proc. Malac. Soc. London, Vol. 12, p. 185, 1917, type (by original designation) Pleurotoma forami- nala Reeve. Type (by subsequent designation, Monterosato, 1875), Pleurotoma histrix Jan = Raphitoma histrix Jan in Bellardi, Mem. R. Accad. Sci., Torino, Ser. 2, Vol. 9, p. 613, pi. 4, fig. 14, 1847, = Pleurotoma hystrix Cristofori and Jan, Cat. Mus., Vol. 2, Pt. 1, p. 10, 1832, + ClathureUa hystrix (Jan), Harmer, Mon. Pateo. Soc, Vol. 68, Plio. Moll. Gt. Brit., Vol. 1, p. 240, pi. 28, figs. 24, 25, 1915, Pliocene of England and Italy, living in the Mediterranean. Shell of medium size, spire moderately high; whorls rounded, sculpture usually in both direc- tions forming a reticulate pattern of raised lines; aperture varying from two-fifths to a haK the length of the shell, ovate, outer lip slightly thickened, with at some growth stages a row of very fine denticu- lations on the inner side, lip roimding back posteriorly to a moderately deep, usually not reinforced posterior notch close to the suture, iimer lip not thickened, columella usually somewhat flexuous, anterior canal not wide, usually sharply defined but very short, often notched behind. Geologic range: Eocene to Recent (Cossmann for ClathureUa). Distribution: Tropical and temperate seas of the Old World. The nomenclature of this genus and of related genera is in an appalling state. The unnecessary succession of generic names proposed for specific synonyms or varieties of Raphitoma reticulata (Renier) and R. purpurea (Montagu), two forms that are so closely related that it might be better to consider them also as conspecific, and for other distinct but closely related species is a test of anyone's patience. Pleurotoma hystrix is merely a variety of purpurea or reticulata (it is difficult to determine which) in which the sharp axial and spiral cords become pointed at the intersections. Furthermore, the synonymy has been complicated by preoccupied names, by erroneous citations of types, by debatable interpretations of the rules of nomenclature, and most of all by the fact that the genus is difficult to separate from its relatives. It is to be noted here that Bellardi did not cite the 610 San Diego Society of Natural History [ Memoirs type of Raphitoma in his preliminary outline of the Pleurotomids, published a few pages ahead of Monterosato's valid designation, for Bellardi had two sections each with a type and did not specify which was the typical section. In Borsonia, treated the same way, the typical section comes second. There is still some doubt about the proper name to use for this much-named group of species. Pleurotomoides, like Lora and Clatlmrella, was proposed not as a new name for Defrancia in a technical sense, but merely as a new genus with Defrancia preoccupied in the synonymy and with several species for which the author felt the need of a name cited as examples. It is the writers' opinion that any species so cited as an example at the time of proposing the name is available as type, provided that the new name is not specifically stated to be "a new name for" the older name preoccupied, and that in such case the later name need not necessarily have the same type as the older, unless by chance the same species be selected for both names independently by the ordinary processes of type fixing. Thus, Cossmann in 1896 cites Carpenter's first species, Clavalula ram Hinds, as the type of Clathurella, and the writers consider this designation valid. Similarly, in 1925, Dautzenberg and Fischer cite Bronn's first species, Murex reticulatus Renier, as the type of Pleurotomoides; and the writers believe that if there were no earlier valid designation, Pleurotomoides would have to be used here instead of Rayhitoma. However, in 1908, Dall cited one of Millet's species as the type of Defrancia and applied it specifically to Clathurella. This action, being later than that of Cossmann, should not affect Clathurella; but in 1918, after explaining again that Defrancia pagoda is the type of both Defrancia and Clathurella, Dall states that Pleurotomoides "must take precedence over Clathurella with the same typical species." Although there may be some question about whether this irregular method of type citing is vaUd or not, it appears so to the writers, and hence Pleurotomoides is here used for the group better known as Pleurotomella instead of for RaphitomaJ Raphitoma is difficult to separate from a number of other small Turrid genera. It is distinguished from Clathurella principally by its larger, relatively thinner, less angulated shells, and by its less heavily armored outer lip and notch; but intergradations occur. It is distinguished from Pleurotomoides by its shallower posterior notch, its higher spire, and somewhat heavier shell. Agathotoma is smaller, thicker, with different sculpture; and the various forms of Clavus usually have larger, heavier shells, with narrower spires and reinforced notches. Raphitoma has more of a Turricula notch than most of these other groups, but the specific relationships seem to tie it more closely with the Clavus branch of the family. Some of the names cited above in the synonymy of this genus have been commonly applied to species occurring on the Pacific coast of North America; but very few of these species, if any, fall within the genus as now restricted. In the middle Miocene of the San Joaquin basin, California, there is a species known as dumbleanus,- which was first referred to Clathurella and is more like Raphitoma in sculpture and shape than any other Cali- fornia species. Nevertheless, it lacks the Turrid notch entirely and shows a weak si- phonal fasciole, so that, as Anderson later pointed out, it is probably a Phos and belongs to the Nassariidce. ' A similar nomenclatorial problem appears in the case of Eucithara Fischer (.Cythara Schumacher not Klein), and the reader may be mter- csted to compare the interpretation of that case. 2 Pleurotoma (Clathurella) dumblei Anderson, Proc. Calif. Acad. Sci., Ser. 3, Vol. 2, p. 204, pi. IS, figs. 60. 61, 1905, not Pleuroloma (Drillia) dumblei Harris, 1895. Phos dumbleana Anderson in Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 183, 1924. Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 611 Genus PERRONA Schumacher, 1817 Perrona Schumacher, Ess. Nouv. Syst. Habit. Vers Test., pp. 66, 218, 1817; Tryon, Man. Conch., Vol. 6, p. 231, 1884; Cossmann, Ess. Pal^o. Comp., Vol. 2, p. 68, 1896. Tomella Swainson, Treat. Malac, pp. 115, 314, 1840, original list comprises lineata Lamarck, davicularis Lamarck, filosa Lamarck, and lineolata Lamarck; type (by subsequent designation, Herrmannsen, Ind. Gen. Malac, Vol. 2, p. 579, Feb., 1849) Pleuroloma lineata Lamarck, figured by Kiener, Sp6c. G6n. et Icon. Coq. Viv., Vol. 5, Pleurotome, p. 47, pi. 22, fig. 1, 1839-40, by Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 11, species 96, 1843, and by Tryon, Man. Conch., Vol. 6, p. 231, pi. 8, figs. 10, 11, 1884; not Tomella Rob.-Desv., 1830, genus of Diptera {fide Herrmannsen). Pusionella Gray, Proc. Zool. Soc. Lend., p. 137, 1847, type (by original designation) Miirex piisio Born = P. nifal (Adanson) Bruguiere, + Buccinuni pusio Born and Gmelin, not Linnsus, figured by Kiener, Spdc. G6n. et Icon. Coq. Viv., Vol. 5, Fvseau, p. 42, pi. 23, figs. 1, pi. 24, figs. 2, 1840, by Reeve, Conch. Icon., Vol. 4, Fttsus, pi. 7, species 30, 1847, and by Tryon, Man. Conch., Vol. 6, p. 235, pi. 31, figs. 13, 14, 1884. Perrona nifal is also illustrated here, plate 25, figures 12a, 12b. Netrum Philippi, Abb. u. Beschr. Conchyl., p. 118, 1850, type Fusus nifal Adanson (fide Dall, 1918). T])j)e (by monotypy), Perrona tritoniuni Schumacher = Murex perron. Chemnitz, Neues Syst. Conch. Cab., Vol. 10, p. 278, pi. 164, figs. 1573, 1574, 1788, = Pleurotoma perronii Reeve, Conch. Icon., Vol. 1, pi. 11, species 94, 1843, also figured by Tryon, Man. Conch., Vol. 6, p. 232, pi. 8, fig. 8, 1884, living, west Africa. Shell tjTiically the shape of a typical Clavaiidn, but often becoming romid-whorled with a much longer or a much shorter columella; sculpture entirely obsolete or with faint remnants of the Clava- tula ribs or spirals, especially on the early whorls; posterior notch about the middle of the outer lip and varying in strength from a deep, angular recession in the lip and in the growth lines to a mere obscure flexure ; iimer lip with a mound of shelly material immediately below the suture in species or varieties that have high-shouldered whorls. Geologic range: Miocene to Recent. Distribution: Tropical waters of all oceans. The transition from Clavatula to this genus, which takes place through the loss of sculpture, is very easy to see, especially in view of the European Miocene species, Clava- tula tuberculosa (Grateloup) and C. spinosa (Grateloup) (figured by Cossmann, op. cit., pi. 4, fig. 19), in which the change can be seen going on. The type species has cylindrical or concave-sided whorls, each whorl with a high shoulder (from which the spines of C. spinosa have disappeared) and an obscure lower angle, the V-shaped notch being midway between the shoulder and the lower angle. From the typical form the series of variations is unbroken through Perrona nifat variety scalarina (Lamarck) to P. nifat, s. s., the type of Pusionella. The shouldered form of scalarina is separable only specifically from P. perron, and the gradation from scalarina to the smoothly round-whorled typical variety offers no opportunity for separation. Hence, Pusionella must be considered a synonym of Perrona. Other species closely allied to P. nifat, such as P. subgranulata (Petit) and P. aculeiformis (Lamarck), resemble Terebra so much in general appearance that Cossmann classified Pusionella with the Terebridoe (op. cit., p. 56). However, Thiele^ has described and figured the radula of P. nifat, as well as that of P. lineata (Lamarck), the type of Tomella Swainson, and finds that both of them agree with the radula of Clavatula; and if you hold in mind the genetic series described above, it is easy to see how these forms with a Terebra-like appearance can be so closely related to Clavatula. Tomella represents the other extreme, derived from typical Perrona by the lengthening instead of the shortening of the canal. In the shouldered species of Perrona, such as P. rapulum (Reeve), there is a mound of shelly material at the top of the inner lip, and this mound is entirely analogous ' Thiele, Wise. Erg. Deutsch. TieJsee-Eipcd., Vol. 17, p. 204, 1925. 612 San Diego Society op Natural History [Memoirs to that found in P. lineata. In no respect is Toniella essentially distinct from Perrona, as is stated by Casey,' and hence no new name is proposed as a substitute for Swainson's name, which appears to be preoccupied. Cossmann and Tryon both put Tomella in the synonymy, and Reeve figures a variety of lineata which connects it with the more typical forms of Perrona (Conch. Icon., Vol. 1, Pleurotoma, pi. 11, species 96a, 1843). The group of forms here included in Perrona, though covering a wide range of variations, is a natural, well-defined unit; and it would be contrary to the facts of nature to subdivide it. Illustra- tions of Perrona nifat and of Perrona obesa (Reeve), a more typical Perrona, are shown on plate 25, figures '12a, 126, and 13a, 136, respectively. Family CANCELLARIIDAE Genus CANCELLARIA Lamarck, 1799 Cancellaria Lamarck, Mem. Soc. Hist. Nat. Paris, p. 71, 1799; Syst. Anim. s. Vert., p. 76, ISOl; Tryon, Man. Conch., Ser. 1, Vol. 7, pp. 65, 66, 1885; Cossmann, Ess. Pal^o. Comp., Vol. 3, p. 10, 1899. Cancdlarivs Montfort, Conchyl. Syst., Vol. 2, pp. 562, 563, 1810. Buccinella Perry, Conch., pi. 27 and text, in part, April, 1811. Merica H. and A. Adams, Gen. Rec. Shells, Vol. 1, p. 277, January, 1854. Euclia H. and A. Adams, op. cil., p. 277, 18.54. f Aphera H. and A. Adams, op. cil., p. 277, 1854, only species, C. tessellata Sowerby. Exechoplychia Cossmann, Ess. Pal^o. Comp., Vol. 5, pp. 189, 190, 1903. Type (by monotypy). Valuta reticulata Linnaeus, figured by Tryon, Man. Conch., Ser. 1, Vol. 7, pi. 2, figs. 25, 26, 1885, Florida and West Indies, Recent. Shell oval, cancellated, ribbed, reticulated, or nearly smooth; last whorl ventricose; aperture oblong, with a short anterior canal, sometimes recurved; columella with strong, oblique plaits, usually two. In view of the individual variability of some species of Cancellaria, it is apparent that the California species have been overnamed. It is likely that habitat has some influence on the shape of the shell and the sculpture, and possibly sexual dimorphism is a factor. It is believed that in many cases the subgeneric and minor subdivisions of Cancellaria will prove more artificial and confusing than natural. These latter have likewise been overnamed. 2 Section Cancellakia, s. s. Shell rather heavy, ovate, with reticulate sculpture; columella with two strong, nearly horizontal plaits above the plait-like end of the coliunella. Cancellaria obesa Sowerby Cancellaria obesa Sowerby, Proc. Zool. Soc. London for 1832, p. 52, 1832; Thes. Conch., Vol. 2, p. 441, pi. 93, fig. 37, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 2, fig. 7, 1856; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 68, pi. 2, figs. 17, 18, questionably 19, 1885; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 210, 1909; Nautilus, Vol. 32, p. 23, 1918; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 154, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 444, pi, 20, figs. 3, 4, 1926; Hanna and Hertlein, Vol. 16, p. 142, 1927. Cancellaria ovaia Sowerby, Proc. Zool. Soc. London for 1832, p. 53, 1832; Thes. Conch., Vol. 2, p. 441, pi. 92, fig. 2, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 4, fig. 18, 1856. ? Cancellaria acuminata Sowerby, Proc. Zool. Soc. London for 1832, p. 53, 1832; Thes. Conch., Vol. 2, p. 458, pi. 92, fig. 1, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 1, figs. 4o, 46, 1856; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 69, pi. 2, fig. 19, 1885. » Casey, T. L.: Trans. Acad. Sci. St. Louis, Vol. 14, p. 126, 1901. ' Dall remarked upon the "totally unnecessary number of names" that have been applied to the subdivisions of Cance»ana. (U. S. Geol. Survey, Prof. Paper 59. p. 30. 1909.) Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 613 Shell ovate, heavy, with reticulate sculpture variable in strength and character; aperture elon- gate, narrow at the top, outer lip lirate within, columella with two strong, nearly horizontal plaits, sometimes an intercalary plait, and a plait-like lower margin ; umbilical chink often present. Pliocene: Imperial formation of Carrizo Creek region, western Imperial County (Hanna); Coronados Island, Gulf of California (Hanna and Hertlein). Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 191S). Recent: Point Abreojos, Lower California (Hemphill), and Gulf of California, Mexico, to Guayaquil, Ecuador. This well-known southern species usually has a low spire with a relatively enormous but moderately ventricose body whorl. The higher spired form was named acuminata by Sowerby and may prove to be a variety. C. obesa is closely related to C. urceolata Hinds. Hanna remarked on the variability of the Pliocene specimens from the Imperial forma- tion, some of which have the sculpture of C. urceolata Hinds while others seem to be rather tjTjical forms of obesa. Cancellaria obesa Sowerby variety planospira, new varietj'^ Plate 27, Figure 4 Shell small, elongate-ovate, body whorl moderately ventricose, upper whorls very slightly con- vex; sculpture finely and evenly reticulate, about eleven spiral riblets on back of body whorl, obsolete near suture; aperture ovate, not so elongate as in typical obesa; columella with two small, oblique plaits, with the margin plait-like, and the upper plait possibly double. Dimensions : Length, 23 mm. ; diameter of body whorl, 13 mm. ; length of aperture, about 10 mm. Type specimen: In the collection of the San Diego Society of Natural History, No. 266. Type locality: Locality 216 S. D. S. N. H., lower Pliocene, east of Fernando Pass, Los Angeles County. Pliocene: Lower Pliocene of the type locality and of Elsmere Canyon, Los Angeles County (H. R. G.)- This form does not appear to be the young of the other species of Cancellaria from nearby localities. It is something like C. reevana Crosse except that the spiral lines are fewer and coarser. In some aspects it recalls C. purpuriformis Kiener. Cancellaria urceolata Hinds Cancellaria urceolata Hinds, Proc. Zool. Soc. London for 1843, p. 47, October, 1843; Zool. Voy. Sulphur, Moll., p. 41, pi. 12, figs. 7, 8, 1844; Sowerby, Thes. Conch., Vol. 2, p. 443, pi. 94, fig. 48, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 5, figs. 23a, 236, 1856; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 69, pi. 2, fig. 20, 1885. "Cancellaria Candida Sowerby," Dall, Nautilus, Vol. 32, p. 23, 1918; probably not C. Candida Sowerby, Conch. lUust., sp. 2, fig. 1, 1832 (?), "Polynesia;" Thes. Conch., Vol. 2, p. 442, pi. 92, fig. 8, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 10, figs. 46a, 466, 1856, "Polynesia;" Tryon, Man. Conch., Ser. 1, Vol. 7, p. 69, pi. 2, fig. 21, 1885, "Polynesia." Shell resembling obesa but higher spired; whorls somewhat roundly tabulated above; sculpture of spiral riblets and axial folds ; aperture ovate and not narrowly prolonged above ; outer lip lirate within, columella with two strong, nearly horizontal plaits. Length, 32 mm. ; diameter, 18 mm. Type locality: Of urceolata, San Bias, Mexico, Recent (of Candida Sowerby, "Poly- nesia"). Pleistocene: At Magdalena Bay, Lower California, Mexico (Dall, as C. Candida Sowerby). Recent: West coa.st of Central America to Mazatlan, Mexico (Tryon). This species can generally be distinguished from obesa by the sloping and often par- tially rounded tabulation below the suture, the more prominent axial sculpture, which is 614 San Diego Society of Natural History [ Memoirs sometimes fold-like, the higher spire, and the less narrow and less elongate aperture. C. obesa appears to attain a larger size, one Recent specimen from Santa Inez, Lower California, measuring nearly 60 mm. in length and about 33 mm. in diameter. The aper- ture of large specimens of obesa is narrowly elongated above, but this feature is not de- veloped in the immature shells. C. Candida Sowerby, as figured, is a lighter colored shell than urceolata. It is supposed to come from Polynesia. Section Crawfordina Dall, 1918 Crawfordina Dall, Proc. Biol. Soc. Washington, Vol. 31, p. 1.38, Nov. 29, 1918; Proc. U. S. Nat. Mus., Vol. .56, p. 306, 1919. Type (by original designation), Cancellaria crawfordiana Dall. Shell elongate-ovate, with axial and spiral sculpture; columella long, with two oblique plaits above the plait-like end of the columella and sometimes small supplementary plaits. This section differs from Cancellaria, s. s., in the more elongate shape, lighter weight, smaller, more oblique plaits, and shorter columella. Cancellaria crawfordiana Dall Cancellaria crawfordiana Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 182, pi. 6, fig. 1, 1891; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 217, 1903; Moody, Univ. Calif. Publ, Geol., Vol. 10, p. 43, 1913; Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 341, pi. 39, figs. 9a, 9b, 1918; Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, p. 153, 1927. Cancellaria crau'fordiana Dall, var.fugleri Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, pp. 15, 16, pi. 54, fig. 9, 1907. Cancellaria oregonensis Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 28, 29, pi. 2, fig. 7, April 2, 1909, not Cancellaria ? oregonensis Conrad, Amer. Journ. Conch., Vol. 1, p. 151, 1865, referring to the U. S. Expl. Exped., Geol. Atlas, pi. 20, fig. 8. Cancellaria aregonsis Dall, op. cit., expl. plate, err. pro oregonensis, 1909. Progabbia crawfordiana Dall, U. S. Nat. Mus., Bull. 112, p. 84, 1921. Cancellaria fugUri .\rnold, Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 51, pi. 1, fig. 3, 1926. Cancellaria oldroydia Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 51, pi. 1, fig. 5, May 31, 1926. Shell of moderate size, rather thin; whorls six, convex, suddenly becoming more convex at the top and plunging over into the chamieled suture; spiral sculpture of about twenty small ridges, narrower than the interspaces, eight or nmc of wluch are visible on the upper whorls; axial sculpture of about twenty riblets, slightly stronger than the spiral ridges; columella straight, callus thin, with two sharp folds and occasionally small secondary folds ; outer lip thin, lirate within ; siphonal f asciole moderate, umbilicus generally absent or covered by callus. Dimensions of a mature Recent specimen: Length, 52 mm.; diameter, 25 mm.; length of aper- ture, 25 mm. Type specimens: Of crawfordiana, oregonensis, and fugleri, in the U. S. National Museum; of oldroydia, in the collection at Stanford LTniversity. Type localities: Of crawfordiana, Drake's Bay, near San Francisco, Recent; of ore- gonensis, Coos Bay, Oregon, Empire formation, upper Miocene; of fugleri, one mile north of Gary, Santa Barbara County, lower Pliocene; of oldroydia, near mouth of Purisima Creek, San Mateo County, Pliocene. Miocene: Empire formation of Coos Bay, Oregon (Dall, as oregonensis). Pliocene: Purisima formation at its type locality, Purisima Creek, San Mateo County (Carson, as oldroydia); Fugler's Point asphalt mine, Santa Barbara County (.Arnold, as vsLTiety fugleri); excavation at Fourth and Broadway, Los Angeles (Moody, as a-aufordia>ia). Pleistocene: Rare in upper San Pedro series at San Pedro (.Arnold, 1903, as crairfordiarm). Recent: Bodega Bay to San Diego, California (Dall, 1921). Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 615 Figures of the type of crawfordiana and the type of oregonensis lead one to suppose that these two forms are distinct, but a study of a collection of fossil and Recent specimens shows that the differences are not significant. Erosion of the surface of the shell changes the aspect of the sculpturing considerably, and variations in the fossils seem to be rather closely paralleled in the Recent specimens. The name oregonensis is preoccupied in Cancellaria, whether Conrad's species is a Trichotropis or not. Section Narona H. and A. Adams. 1854 Narona H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 277, January, 1854; Cossmann, Ess. Paleo. Comp., Vol. 3, p. .5, April, 1899. Frogabbia Dall, Proc. Biol. Soc. Washington, Vol. 31, p. 138, November 29, 1918; Proc. U. S. Nat. Mus., Vol. 56, p. 306, August, 1919. Type (by subsequent designation, Cossmann, 1899), Cancellaria clavatula Sowerby, 1832; Thes. Conch., Vol. 2, p. 445, pi. 92, fig. 13, pi. 95, fig. 67, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 11, figs. 52a-c, 1856; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 75, pi. 4, fig. 61, 1885; Panama to Paita, Peru; Recent; also Pliocene of California. Shell elongate-ovate, typically with axial folds, which are sometimes reduced to nodes on the upper parts of the whorls, or with strong nodes or blunt spines on the shoulders, and with spiral ribs; columella with two very oblique folds. It is impossible to use all the subdivisions of Cancellaria that have been proposed in the literature. Some of the characters upon which the subdivisions have been founded occur sporadically among a number of species which are not uniformly closely related, and even combinations of characters (generally more reliable than single characters) do not always furnish the key to a natural grouping of the subgenera and sections. It is possible that the anatomical characters, when well enough known, will permit of a natural sub- division of the genus ; but such a subdivision would be of little service to those who must study extinct fossil forms, unless the distinctive anatomical features can be correlated with shell characters. Until the genus has been critically monographed, it is more conservative to use broadly the early-proposed names than to delimit these names too closely, for the recentl}^ coined names apply to very minor groups and often mean little or nothing bio- logically. The creation of superfluous names usually complicates the literature, leads to confusion through differences of opinion among authors, and conceals the real geologic and geographic relationships of small groups of species, all for the sake of differences in taxonomy which are not differences in phylogenetic relationships. Cancellaria clavatula Sowerby Plate 27, Figure 2 Cancellaria clavalula Sowerby, Proc. Comm. Sci. Zool. Soc. London for 1832, p. 52, Jime, 1832; Thes. Conch., Vol. 2, p. 445, pi, 92, fig. 13, pi. 95, fig. 67, 1849; Reeve, Conch. Icon., Vol. 10, CanceUaria. pi. 11, figs. .52(i-c, 1856; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 75, 1885; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 209, 1909. Shell fusiform to elongate-ovate, spire high, acute; sculpture of spiral threads and axial folds or ribs with occasional heavier, varix-like ribs; aperture ample, not narrowed above; columella tenuous at the end, with two very oblique plications. Pliocene: Basal Pliocene of loc. 216, east of Fernando Pass, Los Angeles County (H. R. G.), Recent: Panama to Paita, Peru (Dall, 1910). The specimen figured is much like Reeve's figure 52a, and although the occurrence is far from the known habitat, the specimen does not seem to differ sufficiently to warrant 616 San Diego Society of Natural History [ Memoirs a distinct name. It is possible that clavatula ranges a considerable distance north of Panama. Cancellaria tritonidia and C. cooperi are larger and the axial sculpture is emphasized on the upper portion of the whorls in the production of nodosities. Cancellaria elsmerensis Englisli Cancellaria chtmnnai)! English, Univ. Calif. Publ. GeoL, Vol. 8, p. 216, pi. 23, fig. 8, 19U. Shell fusiform, spire elevated, whorls five to six; whorls of spire angulated, angulation absent on the body whorl; whorls ornamented by ten to twelve longitudinal ridges, on the body whorl these ridges becoming low and irregular in shape; whorls with three or four faint spiral hues which are absent on the body whorl except for a small area on the posterior part of the columella; aperture oval; outer lip thin; columella encrusted, smooth except for two acute pUcations anteriorly, callus ex- tending above the suture ; canal short, straight. Altitude, 25 mm. ; width, 12 mm. ; width of aperture, 5 mm. ; length of aperture, equal to half the total height of shell. Type specimen : In the University of California collection. Type locality: Elsmere Canyon, Los Angeles County, lower Pliocene. Pliocene: Lower Pliocene of the type locality. English compared this species to C. cooperi Gabb, from which he stated it differed in its smaller size, in the absence of angulation on the body whorl, and in the irregular ridges and growth lines on the body whorl. It may be close to C. clavatula Sowerby, part of its difference in appearance being due to erosion. It seems to be a rare species. When more specimens are known, its relationships with other species may be revealed. Cancellaria tritonidea Gabb Plate 27, Figure 8 Cancellaria {Euclia) tritonidea Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 11, pi. 2, fig. 18, 1866, p. 79, 1868-9. Cancellaria tritonidea Gabb, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 231, 1888; Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 183, 1891; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 218, pi. 7, fig. 5, 1903; U. S. Geol. Surv., Bull. 396, pp. 31, 158, pi. 26, fig. 10, January 15, 1910; Bull. 398, pi. 48, same figure, 1910; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; McLaughlin and Waring, Calif. State Mining Bure.au, Bull. 69, Map Folio, pi. 1, fig. 51, 1914; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 220, table opp. p. 230, 1917; WaterfaU, Vol. 18, pp. 77, 78, 79, 1929. Cancellaria perrini Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 56, pi. 3, fig. 4, 1926. Shell large, fairly heavy, whorls about six, body whorl large; all of the whorls more or less angu- lated, the shoulder appearing at about the middle of the exposed part of the upper whorls and about a quarter of the distance below the suture of the body whorl ; sculpture of about seventeen fairly coarse spiral lines below the shoulder, the number sometimes increased by intercalaries on the body whorl of large specimens, and of about six spiral lines above the shoulder; axial ridges or folds more or less clearly developed, finer and more closely spaced on the earlier whorls so that the axial and spiral sculpture there usually form a nearly equal warp and woof, on later whorls the ridges tending to grow sharper or to die out in broad folds, averaging twelve on the body whorl and eighteen on the penultimate whorl; the ridges or folds often developing into prominent nodes on the shoulder; suture distinct, abutting sometimes against the shoulder, sometimes against the wall of the precedmg whorl; columella covered with a heavy callus, which sometimes extends above the body whorl, showing above the suture on some of the earlier whorls ; columella with two strong plaits, sometimes straight and simple, with a moderate siphonal fasciole, sometimes swollen and recurved, with one or two in- distinct minor plaits and occasionally a marked umbilical chmk partially covered over by the callus ; outer lip simple; posterior canal a shallow inverted trough; anterior canal rounded, shallow, narrow, and short, sometimes slightly recurved. Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 617 Single specimens of the varieties of Cancellaria tritonidea appear rather distinct, but large collections generally show intergradation between all of them. Many of the varieties occur in the same deposit. At one time Dall (1914) considered C. tritonidea and C. veiusta Gabb the young and the gerontic individuals, respectively, of C. cassidiformis Sowerby; but this is a rather extreme view. Variety tritonidea, s. s. Spire comparatively low; early whorls with nearly equal axial and spiral sculpture, convex; later whorls with strong angulation, slightly concave above the shoulder; prominent nodes along the shoulder on the axial folds, which are distinguishable nearly to the base of the body whorl. Dimensions (from Arnold, 1903) : Longitude, 90 mm. ; diameter of body whorl, 60 mm. ; length of aperture not including canal, 50 mm.; apical angle, 75 degrees. Type specimen: In the University of California collection, No. 11,998. Type locality: San Pedro, presumably Pleistocene. Pliocene: Lower Pliocene at Elsmere Canyon, Los Angeles County (English, 1914; Carson, as C. perrini); Pecten coalingensis zone of Coalinga region; upper Sargent of San Benito County (Nomland, 1917) ; "Pico" formation of Ventura region (Waterfall). Pleistocene: Coyote Creek, Ventura County, and San Pedro (Cooper); Barlow's Ranch, just east of Ventura (Arnold, 1903); "Saugus" near Ventura (Waterfall); San Pedro, presumably Pleistocene (Gabb); rather rare in the upper San Pedro series of San Pedro (Arnold, 1903). Typical Cancellaria tritonidea Gabb ranges from the lower Pliocene to the upper Pleistocene but is absent in the cold-water zones of the Pleistocene of southern California. The folds on the body whorl of the type of perrini are well hidden within the aperture. The variety rapa Nomland differs in the lack of nodes and axial folds on the later whorls, and in the weaker angulation. The specimen named perrini is somewhat intermediate between tritonidea, s. s., and variety rapa but is closer to the former. Cancellaria tritonidea Gabb variety rapa Nomland Cancellaria rapa Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 240, pi. 11, figs. 1, lo, 1917. Cancellaria elodise Carson, Bull. Southern Calif. Acad. Sci., Vol. 25, p. 49, pi. 1, fig. 1, 1926. Cancellaria palmeri Carson, np. cit., p. 5.5, pi. 2, fig. 4, 1926. Like tritonidea, s. s., but lacking the nodes and axial folds on the later whorls; angulation on the shoulder of the whorls less and the sutures more nearly tangential. Type specimens: Of rapa, in the University of California collection. No. 11,097; of elodice and palmeri, in the Stanford University collection, Nos. 109 and 107, respectively. Type localities: Oirapa, near Coalinga, Pliocene {?),fide Nomland; of elodice, Fugler's Point, Santa Barbara County, Pliocene; of palmeri, beach bluffs at Capitola, Santa Cruz County, Purisima formation, Pliocene. Pliocene: At the type localities, as above. The paratype of C. hamlini Carson has some resemblance to this variety. The lack of nodes and axial folds on the variety rapa may be merely a function of the more rounded whorls. Cancellaria tritonidea Gabb variety hamlini Carson Cancellaria hamlini Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 51, pi. 1, figs. 4, 6, 1926. Shell like that of the variety rapa but with more delicate sculpture and the shape more tapering as in the variety altispira. Type specimen: In the collection at Stanford University, No. 110. 618 San Diego Society of Natural History [ Memoirs Type locality: Elsmere Canyon, Los Angeles County, lower Pliocene. Pliocene: Lower Pliocene of the type locality. The type of hamlini, which is a young specimen, bears a superficial resemblance to C. craivfordiana Dall, but the strongly rounded shoulders and channeled sutures of the latter suffice to distinguish it. Cancellaria tritonidea Gabb variety altispira Gabb Plate 27, Figure 7 Cancellaria alHspira Gabb, Geol. Surv. Calif., Pateo., Vol. 2, pp. 50, 79, pi. 14, fig. 7, 1868-9. Cancellaria netvhallensis Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 56, pi. 3, fig. 3, 1926. Cancellaria (Progahhia) allis-pira Gabb, Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, pp. 411, 412, ])1. 31, figs. 9, 9a, 1927. Shell like that of tritonidea, s. s., but with a proportionately higher spire, which is about as long as the aperture, and with a less expanded body whorl. Length, 50 mm. ; diameter of body whorl, 30 mm.; apical angle, 55°. Type specimens: Of altispira, in the Museum of Comparative Zoology of Harvard University, Whitney Collection, No. 27,812, fide Stewart; of newhallensis, in the collection at Stanford University, No. 108. Type localities: Of altispira, San Fernando Pass, Los Angeles County, Pliocene; of newhallensis, Elsmere Canyon, Los Angeles County, Pliocene. Pliocene: Lower and middle Pliocene at and near the type localities (Gabb; Carson). The sculpture of the upper whorls of the types of both altispira and newhallensis re- calls C. crawfordiana. Lidividuals of Cancellaria spengleriana Deshayes of the Japanese fauna that are not fully mature are very similar to variety altispira. Cancellaria tritonidea Gabb variety femandoensis Arnold Plate 27, Figure 1 Cancellaria femandoensis Arnold, Proc. IT. S. Nat. Mus., Vol. 32, p. 535, pi. 50, fig. 4, June 15, 1907; U. S. Geol. Surv., Bull. 309, pi. 40, fig. 4, 1907; English, Univ. Calif. Publ. Geol., Vol, 8, p. 210, 1914. Cancellaria quadrala Moody, LIniv. Calif. Publ. Geol., Vol. 10, p. 56, pi. 1, fig. 6, 1916, not Cancellaria quadrata Sowerby, Min. Conch. Gt. Brit., Vol. 4, p. 83, pi. 360, 1823. Cancellaria femandoensis tribulus Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 238, pi. 12, figs. 1, la, 1917, not Volula tribulus Brocchi, 1814, a Cancellaria. Cancellaria angelana Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 159, March IS, 1924, new name for C. quadrala Moody. Shell like that of the tyijical variety of tritonidea but with stronger a.\ial ribbing on the earlier whorls. Type specimens: Oi femandoensis, in the U. S. National Museum, No. 164,956; of quadrata Moody, in the collection at the University of California, No. 11,083; of tribulus Nomland, in the same collection, No. 11095. Type localities: Oi femandoensis, Elsmere Canyon, near Pacific Coast Oil Company's wells, 2J^ miles southeast of Newhall, Los Angeles County, lower Pliocene; of quadrata Moody, Fourth and Broadway, Los Angeles, upper or upper middle Pliocene; of tribulus Nomland, Garza Creek, Kings County, San Joaquin Valley, Turritella nova zone, lower middle Pliocene. Pliocene: Lower Pliocene of Elsmere Canyon (Arnold; English), and of S. D. S. N. H. loc. 216, east of Fer- nando Pass, Los Angeles County (H. R. G.); middle Etchegoin of Ivings County (Nomland, as variety tribulus); upper or upper middle Pliocene of Los Angeles (Moody, as quadrata). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 619 The type of this variety lacks the adult body whorl. The variety fernandoensis is possibly of more value than some of the others here recognized, but is clearly not a dis- tinct species. The upper whorls of some specimens of tritonidea look much like Arnold's type figure oi fernandoensis. Cancellaria tritonidea Gabb variety crassa Nomland Cancellaria crassa Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 237, pi. 12, figs. 7, 7a, .\pril 19, 1917. Shell like that of xarioiy fernandoensis but with fewer and stronger axial ribs. Type specimen: In the collection at the University of California, No. 11,098. Type locality: On the north bank of Waltham Creek, Coalinga district, Turritella nova zone, lower middle Pliocene. Pliocene: At the type locality. (Nomland). The appearance of the type of this variety is quite different from that of typical speci- mens of C tritonidea; but when all the variants of the species are studied together, it is very hard to decide where to draw the line between valid and invalid distinctions. Until much larger collections of C. tritonidea and its variants are available for study it must re- main to some extent a matter of personal opinion whether this or that form is synony- mized or kept distinct. Possibly too many varieties of tritonidea have been here recog- nized, but at least a first step has been taken in disposing of too many names. The group to which CanceUaria tritonidea and its varieties belong is represented in the lower Miocene (in part Oligocene) by Cancellaria vetusta Gabb' and its allies, including C. andersoni^ and C. ramonensis Clark. ^ Cancellaria cooperi Gabb Cancellaria (Narona) cooperi Gabb, Proc. Calif. Acad. Sci., Vol. 3, p. 186, 1865. Cancellaria cooperi Gabb, Tryon, Man. Conch., Ser. 1, Vol. 7, p. 76, pi. 4, fig. 66, 1885; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 211, pi. 22, fig. 2, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 217, pi. 7, fig. 8, 1903. Cancellaria (Progahhia) coopeH Gabb, Dall, U. S. Nat. Mus., Bull. 112, p. 83, pi. 5, figs. 3, 4, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 1.52, pi. 11, fig. 14, 1927. Shell large, elongate; whorls six, angulated at the upper third of the exposed portion, sometimes the lower two-thirds divided by a slightly stronger spiral line; spiral sculpture finer but otherwise much like that of C. tritonidea; axial sculpture of prominent, varix-like ribs, about fifteen on every whorl except the first, which is usually worn smooth and the last, on which the ribs sometimes de- generate into irregular folds and growth lines; columella heavily encrusted with callus, bearmg a prominent fold just above the middle and two oblique plications below the middle ; outer lip internally lirate. Dimensions: Longitude, 80 mm.; diameter of body whorl, 35 mm.; length of aperture mcluding canal, 42 mm.; apical angle, 40°. Type specimen: "In Geological Survey, MoUusca Survey Cabinet, No. 463," fide Oldroyd ( = University of California collection ?) . Type locality: San Diego; Recent. Pleistocene: "Rare in the upper San Pedro series of San Pedro; five specimens found" (Arnold). Recent: Monterey, California, to Coronado Islands off San Diego (Dall). 1 Geol. Surv. Calif., Palaeo., Vol. 2, p. 12, pi. 2, fig. 19, 1866. 2 Clark, Univ. Calif. Publ. Geol., Vol. 11. pp. 80. 82, 97, pi. 23, fig. 4, 1918. ■ op. cit., p. 186, pi. 23, fig. 7, 1918. 620 San Diego Society of Natural History [Memoirs This species is a large, high-spired form. Dall made it the type of Progahbia, a sub- division that appears to be entirely unnatural, for coo-peri is very closely related to tritonidea, and might even be considered a variety of tritonidea. C. spengleriana Deshayes/ of the Oriental Pacific fauna, is of the same clan. Cancellaria fergusoni Carson CanceUaria fergvsoni Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 53, pi. 1, figs. 7, S, 1926. Shell like that of Cancellaria cooperi but lower spired, with fewer and weaker axial ribs. Type specimen: In the collection at Stanford University, No. 106. Type locality: Barlow's Ranch, just east of Ventura, probably Pleistocene (see dis- cussion below). Pliocene: Fugler's Point, Santa Barbara County (Carson). Pleistocene: Barlow's Ranch, near Ventura (stated to be Pliocene by Carson). This Cancellaria might be considered a variety of cooperi, but it has some resemblance to altispira Gabb. C. cooperi has more numerous axial ribs (about fifteen to a whorl) than the type oi fergusoni (which has ten axial ribs per whorl) . Until its relationships are better understood, it is tentatively retained as a distinct species. The holotype is labeled as having come from "Upper San Pedro beds, Barlow's Ranch, Ventura County" collected by Delos Arnold, though Carson attributes an upper Pliocene age to the specimen. The discrepancy may be due to the varying opinions re- garding the age of the upper marine sands in the foothills at Ventura. Cancellaria sanctae-mariae Carson Cancellaria sanclse-marise Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 57, pi. 3, fig. 5, 1926. Shell short, fusiform, with a sloping, slightly concave tabulation on the upper part of the whorls, suture appressed ; sculpture of fine spiral threads, each fourth thread slightly accentuated, and of low, slightly noded axial rit>s on the upper whorls, becoming obsolete on the body whorl; aperture oval, columella with two plications, the lower very oblique and tending to become distinct from the lower margin of the columella, the upper only slightly oblique. Dimensions: Height, 43 mm.; diameter, 23 mm.; apical angle, about 62°. Type specimen: In the collection at Stanford University, No. 101. Type locality: Fugler's Point, Santa Maria district, Santa Barbara County; Pliocene, presumably lower part. Pliocene: Fugler's Point, Santa Barbara County, lower or middle Pliocene (type locality). The subdued axial sculpture and fine spiral threads serve to distinguish this form. It may prove to be but a variety of fergusoni, from which it differs in the very subdued nodosity on the shoulder. It differs from C. tritonidea var. rapa Nomland in its much finer spiral sculpture and in the more definite shoulder on the whorls. Cancellaria cassidiformis Sowerby Cancellaria cassidiformis Sowerby, Proc. Comm. Sci. Zool. See. London for 1832, p. 53, June, 1832; Thes. Conch., Vol. 2, p. 439, pi. 92, fig. 15, 1849; Reeve, Conch. Icon., Vol. 10, CanceUaria, pi. 2, figs. 8a, 8b, 1856; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 66, pi. 1, fig. 1, 1885; Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 183, 1891; Vol. 37, p. 209, 1909; Nautilus, Vol. 32, p. 23, 1918. ' Ency. Mfith., Vol. 2, Pt. 1, p. 185, 1830. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 621 Shell short, ])lump, spire relatively low but sharp apically; whorls tabulated or shouldered; sculpture consisting of spiral cords, alternate cords often more emphasized, and axial ribs which be- come sharp nodosities on the margin of the tabulation ; aperture ovate, with two promment, oblique plaits, the lower one more oblique than the upper and the lower margin of the columella often plait- like ; parietal wall with a callosity; umbilicus closed or but a mere chink. Length, 40 to 60 mm.; width, 25 to 40 mm. Type locality: Panama, Recent. f Pliocene: Santa Barbara County (Dall, 1891, see discussion below). Pleistocene: Magdalena Bay, Lower California (Dall, 1918), and about seven miles north of Turtle Bay, Lower California, Mexico (in the collection of A. M. Strong, presumably Pleistocene). Recent: Gulf of California, Mexico, to Paita, Peru (Dall, 1909). C. cassidiformis is a close relative of C. vetusta, C. tritonidea, and their allies. Dall stated (1891) that cassidiformis occurs as a "fossil in the Miocene or Pliocene formation of Santa Barbara County," and that C. tritonidea and C. vetusta were "based on a young and a very aged specimen, respectively, of this variable species." Cancellaria triangularis Nelson,^ of the Peruvian Neocene, is also closely related. Cancellaria hemphilli Dall Plate 27, Figures 3, loa, 156 Cancellaria hemphilli Dall, U. S. Geol. Surv., Prof. Paper 59, p. 30, pi. 14, fig. 5, April 2, 1909. Shell elongate, solid, of about seven whorls; whorls gently convex up to a narrow, sunken tabula- tion; sculpture of eight to eleven prominent, moderately sharp, nearly vertical axial ribs, which are a little swollen and mcurved at the tabulation, and a few faint, almost obsolete spiral lines; columella slender, curved, with two thin, sharp, prominent plaits, more or less glazed by a layer of enamel; anterior canal long, curved ; no umbilicus visible. Dimensions: Height, 32 to 38.5 mm.; diameter, 14 to 19 mm. Type specimen: In the U. S. National Museum, No. 135,050. Type locality: San Diego well, lower part of Cabrillo Canyon, Balboa Park, San Diego; middle Pliocene. Pliocene: San Diego well, middle Pliocene; S. D. S. N. H. locality 263, middle Pliocene between Pico Canyon and Fernando Pass, Los Angeles County; loc. 217b, middle Pliocene of Holser Canyon, Los Angeles County (H. R. G.). This species is quite different from other California species of Cancellaria; and al- though the present writers do not know to what section it should be assigned, they do not believe it belongs to Narona. C. hemphilli is similar to Cancellaria thomasiana Crosse from the China seas. The specimen illustrated on plate 27, figure 3, seemes hardly separ- able specifically from the Chinese species. So far as known, C. hemphilli occurs only in the San Diego horizon of the Pliocene. Cancellaria amoldi Dall Cancellaria amoldi Dall, U. S. Geol. Surv., Prof. Paper 59, p. 29, pi. 14, fig. 7, 1909. Type specimen: In the U. S. National Museum, No. 135,038. Type locality: San Diego well, San Diego, California; Pliocene. Pliocene: San Diego well (Dall). Cancellaria amoldi recalls C. tritonidea variety fernandoensis Arnold but has a more prominent siphonal fasciole and an open umbilicus. Dall placed this species in the section ' Trans. Conn. Acad. Arts and Sci., Vol. 2, pt. 1, p. 191, pi. 6, fig. 10, 1871. 622 San Diego Society of Natural History [ Memoirs Merica H. and A. Adams, although it could as well be placed in several other supposed subdivisions. The open umbilicus does not seem to warrant removing it sectionally from other Pliocene species that lack this one character but are like it in others. It does not have the widely open and deeply perforate umbilicus nor the fantastic tabulation of Trigona pellucida Perry ( = Cancellaria trigonostoma Lamarck), the monotype of Tri- gona Perry.' Genus ADMETE Kroyer in MoUer, 1842 Admete Kroyer, Moller, Index Moll. Groenl., p. 15, 1842. Type (by monotypy), Admete crispa Moller, a minor variety of Cancellaria couthouyi Jay. Shell thill, rather small, with very weak plaits on the columella. Admete couthouyi (Jay) Not Triionium viridulum Fabricius, Fauna Groenl., p. 402, 1780, the type of Lora, see Lora. Cancellaria buccinoides Couthouy, Boston Journ. Nat. Hist., Vol. 2, p. 105, pi. 3, fig. 3, 1838, not of Sowerby, 1832. Cancdlaria couthouyi Jay, Cat. Shells, p. 77, 1839; de Kay, Zool., New York, p. 138, pi. 7, fig. 160, 1843; Sowerby, Thes. Conch., Vol. 2, p. 449, pi. 96, figs. 100, 101, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 18, fig. 86, 1856. ? Admete crispa Moller, Ind. Moll. Groenl., p. 15, 1842. ? Cancellaria subangulosa Wood, Crag MoUusca, Vol. 1, p. 66, pi. 7, figs. 20a, 206, 20aa, 20b6, 1848. Cancellaria "mridida Fabricius," Sowerby, Thes. Conch., Vol. 2, p. 449, pi. 96, fig. 102, 1849; Reeve, Conch. Icon., Vol. 10, Cancellaria, pi. 18, fig. 85, 1856. Admete "iiiridula Fabricius," Middendorff "Beitr. Malac. Ross.," M^m. Acad. Imp. Sci. St.-P^tersbourg, Ser. 6, Vol. 6, Pt. 2, pi. 9, figs. 13, 14, ISiQ, fide Dall, 1884; Chenu, Man. Conchyl., Vol. 1, p. 278, te.xt figure, 1853; Dautzenberg and Fi.scher, Res. Camp. Sci. Albert, I, Prince de Monaco, Fasc. 37, pp. 55-59, 1912. ? Admete middendorffiana Dall, Proc. U. S. Nat. Mus., Vol. 7, p. 524, 1884; Vol. 24, p. 516, pi. 38, fig. 6, 1902; U. S. Nat. Mus., Bull. 112, p. 84, 1921. "Admete gracilior Carpenter," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 219, pi. 7, fig. 4, 1903, not of Carpenter. Admete couthomji Jay, Dall, U. S. Nat. Mus., Bull. 112, p. 84, pi. 16, fig. 7, 1921. Admete couthouyi "gracilior Carpenter," Dall, U. S. Nat. Mus. Bull. 112, p. 84, 1921. Pliocene: Bath-house Beach, Santa Barbara (Arnold); Pliocene of England; etc. Pleistocene: Lower San Pedro series at Deadman Island, Los Angeles County; Port Los -Ajigeles, near Santa Monica (Arnold; Dall; as gracilior); etc. Recent: Circimiboreal; Arctic Sea to San Diego, California. This variable species has a number of synonyms not included above. It is a matter of personal opinion which named forms can be reasonably considered valid varieties. The form 'middendorffiana Dall, is a low-spired variation; typical couthouyi is characterized by small axial plications; Admete calif ornica Dall may be another variety; even modesta may not be specifically distinct; and the status of rhyssa is problematical. Admete modesta (Carpenter) Plate 27, Figure 5 Cancellaria modesta Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 32, January, 1865; Newcombe, Nautilus Vol. 10, p. 18, 1896. Cancellaria (Sveltia) modesta Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 84, 1921; Oldroyd, Stanford Univ. Pub). Geol., Vol. 2, Pt. 1, p. 154, 1927. Type specimen: In the U. S. National Museum. Type locality: Neah Bay, Washington. * Conchology, expl. to pi. 51, figs. 1, 2, January 1, 1811, not Trigona Megerle von Muhlfeld, 1811. Trigonostoma Blainville, 1826, is a synonym. VoLDME I ] Pliocene and Pleistocene Mollusca of California 623 Pliocene: S. D. S. N. H. loc. 218, upper Pliocene, Santa Barbara zone, in Sulphur Canyon east of South Mountain, Ventura County (H. R. G.). Recent: Aleutian Islands, Alaska, to Neah Bay, Puget Sound (Dall). The specimen figured is less tabulate than those commonly classified as this species. Cancellaria unalaske7isis Dall may prove to be the young. The true graciJior Carpenter in Gabb is probably a variety of modesta. Admete rhyssa Dall Admete rhyssa Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 306, 1919; IJ. S. Nat. Mus., Bull. 112, p. 84, 1921 ; T. S. Oldroyd, Proc. TT. S. Nat. Mus., Vol. 65, Art. 22, p. 11, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 1, Pt". 1, p. 156, 1927. Type specimen: In the U. S. National Museum, No. 211,241. Type locality: U. S. Bureau of Fisheries station 4343, off South Coronado Island, Lower California, Mexico (just south of San Diego, California). Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, "one specimen" (T. S. Oldroyd). Recent: Santa Rosa Island, California, to South Coronado Island, Mexico (Dall). This species is as yet unfigured. If the genus were carefully monographed it is likely that a considerable number of species would be reduced to varietal standing or synonymy. Pleurotoma (Clathurella) duvMei Anderson,' from the middle Miocene beds of Kern River, might be an Admete; but it probably is not. Superfamily Rhachiglossa Family OLIVIDAE Genus OLIVA Martyn, 1786 Oliva Martyn, Univ. Conch., Vol. 3, explanatory table and pi. Ill, 1786; Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 70, 1799; only example. Valuta oliva Linnaeus; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 73, 1883; Dall, Proc. U. S. Nat. Mus., Vol. 29, p. 428, October, 1905; Woodring, Carnegie Inst., Publ. No. 385, 1928. Type (by subsequent designation, Dall, 1905), Oliva corticata Martyn, 1786, "Coasts of Guinea" (?), = ? 0. incrassata Solander (0. angulata 'Lam.axck, fide Dillwyn, Descript. Cat. Rec. Shells, Vol. 1, p. 516, 1817), figured as 0. angulata Lamarck by Tryon, Man. Conch., Ser. 1, Vol. 5, pi. 29, fig. 84, 1883. Shell ovate-cylindrical, smooth, polished, spire low, suture channeled; aperture long, narrow, emarginate anteriorly, channeled posteriorly; outer lip sometimes thickened, parietal wall covered with callus, marked by fine plaits; operculum and epidermis lacking. Oliva is distinguished from Olivella by its larger average size, lower spire, more elongate aperture, and lack of operculum. Woodring has discussed the genotype in the reference given above. Most of the species of Oliva are confined to the tropics or warm temperate seas. Oliva corticata Martyn Oliva corticata Martyn, Univ. Conch., Vol. 3, pi. HI, left figure, and explanatory table, 1786; Dillwj-n, Descript. Cat. Rec. Shells, Vol. 1, p. 516, 1817, in part. Type locality: Probably west coast of Mexico, Central America, or Panama region, stated to be "Coast of Guinea," probably in error (see discussion below). ' Proc. Calif. Acad. Sei., Ser. 3 (Geol.), Vol. 2, p. 204, pi. 15. figs. 60. 61, 1905; see Phoa dumbleanus Anderson in Hanna. 624 San Diego Society or Natural History [Memoirs A careful comparison of Martyn's colored figure of Oliva corticata with Recent speci- mens labeled "0. angulata Lamarck" from the west Mexican coast leads to the opinion that the two represent the same species. There is considerable variation in the size and prominence of the spu-e and also, to a lesser degree, in the general shape and apertural characters of the Mexican specimens of angulata. Many of the older authors made serious errors in locality and it is not improbable that Martyn's shell came from the tropical west American coast instead of the west African. On the other hand, many species of the Panama region are strikingly similar to west African species, and corticata may fall in that group of close analogues. Specimens of Oliva incrassata Solander (+0. angulata Lamarck) are generally figured as having a heavier lip and callus and a more angulated shoulder than that shown in Martyn's figure of corticata, and it is here pro- posed to use incrassata in a varietal sense for the latter form. Oliva corticata Martyn variety incrassata (Solander) Volvta incrassata Solander, Portland Catalogue, p. 171, 17S6, fide Johnson, 1911. Oliva angulata Lamarck, Ann. Mus. Hist. Nat. Paris, Vol. 16, p. 310, 1811; Reeve, Conch. Icon., Vol. 6, Oliva, pi. 1, figs, la, 16, 1850; Marrat, in Sowerby, Thes. Conch., Vol. 4, Oliva, p. 3, pi. 1, figs. 7, 8, 1870, "Mazatlan; Gulf of Nicoya;" DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 210, 1909. Oliva incrassata Solander, Johnson, Nautilus, Vol. 24, p. 122, 1911; Dall, Vol. 22, p. 23, 1918. Oliva angulata Linnseus, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 149, 151, 1924. Pleistocene: Magdalena Bay, Lower California, Mexico, lower Pleistocene (Dall, 1918; Jordan, 1924, as angulata) ; upper Pleistocene, coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Magdalena Bay, Lower California, Mexico, to Peru (DaU, 1909). This variety differs from the typical form in the shorter, broader shape, more prominent shoulder, heavier outer lip, and thicker callus on the parietal wall near the posterior emargination. Typical 0. corticata, as illustrated by Martyn, has a less robust, more graceful shell. Specimens from the Gulf of California agree perfectly with Martyn's figure. Oliva spicata (Bolten) Porphyria spicata Bolten, Mus. Boltenianum, p. 35, 1798. Porphyria arachnoidea Bolten, op. cil., p. 36, 1798. Oliva arenosa Lamarck, Ann. Mus. Hist. Nat. Paris, Vol. 16, p. 315, 1810, in part; Tryon, Man. Conch., Ser. 1, Vol. 5, pi. 27, fig. 62, 1883, fide Vanatta. Oliva reticulata Lamarck, Reeve, Conch. Icon., Vol. 6, Oliva, pi. 27, in part, 1850. Oliva spicata Bolten, Johnson, Nautilus, Vol. 24, p. 121, 1911; Vanatta, Vol. 29, p. 70, 1915; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 452, pi. 21, figs. 4, 5, 1926; Hanna and Hertlein, Vol. 16, p. 143, 1927. Pliocene: Coyote Mountain, Imperial County (Hanna); Santa Antonita Point, Coronados Island, Carmen Island, and Las Galeras Island, GuK of California, Mexico (Hanna and Hertlein). Pleistocene: Near Las Bolsas Mines, Santa Rosalia, Lower California, Mexico (coll. by M. E. Touwaide); upper Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Point Abreojos, Lower California, Mexico, to Guayaquil, Ecuador. This variable species usually has a higher spire than 0. corticata variety incrassata and a smaller callus deposit on the body whorl near the suture. There are several named varieties. In the collections at Stanford University there are deformed specimens from San Ignacio Lagoon, Lower California, that have strong axial folds. These specimens measure only about 40 mm. in length. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 625 Oliva testacea Lamarck OUva testacea Lamarck, Ann. Mus. Hist. Nat. Paris, Vol. 16, p. 324, 1810; Lamarck, Hist. Nat. Anim. s. Vert., Desh. & M. Edw. Ed,, Vol. 10, p. 627, 1844; Reeve, Conch. Icon., Vol. 6, Oliva, pi. 18, fig. 36, 1850; Marrat, in Sow- erby, Thes. Conch., Vol. 4, Oliva, p. 26, pi. 21, figs. 334, 335, 1870; Tryon, Man. Conch., Ser. 1, Vol. 5, pi. 36, fig. 65, 1883; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 210, 1909. Type locality: "Habite la mer du Sud, sur les cotes du Mexique." Pleistocene: Coast of Oaxaca, Mexico (coll. by Palmer). Recent: Mazatlan, Mexico, to Cobija, Chile (Dall, 1909). This species has a wide aperture, flaring anteriorly, but not extending as high on the body whorl as in the preceding species. It resembles an OUvella. The west African 0. hiatula Gmelin is very similar, but from the data on hand appears to have on the average a lower spire. Tryon considered them identical. Genus OLIVELLA Swainson, 1831 OHvella Swainson, Zool. Illustr., Ser. 2, Vol. 2, Expl. pi. 58 (Oliva, pi. 2), 1831; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 63, 1883; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 31, 1909; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 229, 1928. Type (by subsequent designation, Dall, 1909), Oliva purpurata Swainson, = 0. dama (Wood), figured by Sowerby, Thes. Conch., Vol. 4, pi. 349, figs. 368, 369, 1870; Pacific coast of Mexico, Recent. The genus OUvella can be distinguished from Oliva by the smaller size of the shells, the more produced spire, and the presence of a horny operculum. The species of OUvella venture into cooler waters than do those of OUva, which are essentially tropical in dis- tribution. OUvella biplicata (Sowerby) Plate 24, Figure 15 Oliva biplicata Sowerby, Cat. Shells Tankerville, Appen., p. 33, 1825; Reeve, Conch. Icon., Vol. 6, Oliva, pi. 20, fig. 48, 1850. OUvella biplicata Sowerby, Swainson, Treat. Malac, p. 82 ("Olimlla" by mistake), pp. 133, 322, text fig. 3, 1840; Cocper, Seventh Ann. Rept. Calif. State Mineralogist, p. 255, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 219, 1903; Keep, West American Shells, Rev. Ed., p. 138, te t fig. 112, 1911; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 221, 1917; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; DaU, U. S. Nat. Mus., Bull. 112, p. 85, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 11, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 160, pi. 26, figs. 20, 20a, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 252, 254, 1929. Oliva {Callianax) biplicata Sowerby, Tryon, Man. Conch., Ser. 1, Vol. 5, ]). 87, pi. 34, fig. 58, 1883. OUvella biplicata lapillus Vanatta, Nautilus, Vol. 29, p. 71, October, 1915; Dall, U. S. Nat. Mus., Bull. 112, p. 85, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 161, 1927. OUvella biplicata angelena T. S. Oldroyd, Nautilus, Vol. 32, p. 34, July, 1918. OUvella biplicata fucana T. S. Oldroyd, Nautilus, Vol. 34, p. 118, pi. 5, fig. 4, April, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 161, pi. 26, figs. 23, 23a, 1927. OUvella biplicata parva T. S. Oldroyd, Nautilus, Vol. 34, p. 119, pi. 5, fig. 7, 1921; I. S. Oldroyd, op. cit., p. 162, pi. 26, figs. 16, 16a, 1927. OUvella biplicata angeUna Oldroyd, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 161, pi. 26, figs. 17, 17a, 1927 (err. pro anyelena). Type specimens: Of biplicata, unknown to authors; of lapillus, in the Academy of Natural Sciences of Philadelphia, No. 111,977; of angelena, fucana, and parva, in the Oldroyd Collection, Stanford University. 626 San Diego Society of Natural History [ Memoirs Type localities: Of biplicata, "West coast of North America"; of lapillus, San Pedro; of angelena, San Pedro, Pleistocene; oi fucana, Straits of Juan de Fuca; of parva, Point Abreojos, Lower California, Mexico. Pliocene: Twelve Mile House, Seven Mile House, San Mateo County; San Diego well, San Diego (Cooper); common in Pecten coalingensis zone of the lower Etchegoin of the Coalinga region; lower Merced and upper Sargent of middle California (Nomland, 1917); "Pico" near Ventura (Waterfall); etc. Pleistocene: "Pliocene" of San Pedro region (Arnold); common in lower and upper San Pedro beds (Arnold; T. S. Oldroyd, also as variety angelena) ; Point Firmin, Los Angeles (Chace) ; Santa Monica palisades (F. C. Clark collection); Pleistocene of Ventura (Arnold); Pacific Beach and foot of Twenty-sixth Street, San Diego (Stephens); upper Pleistocene, Campbell Ranch, near Goleta, Santa Barbara County (U. S. G.); lower Quaternary of Magdalena Bay and upper Pleistocene of San Quintin Bay, Lower Calif oi-nia, Mexico (Jordan); etc. Recent: British Columbia to Lower California, Mexico. This is a rather stout, heavy-shelled species, with from one to four plicse on the base of the columella, above which there appears to be an excavation. It is common in many Pleistocene localities in southern California. It is heavier, larger, and less elongate than bcetica. It is not probable that the strains of the various named minor variants could keep pure in view of their known ranges. Olivella dama (Wood) Voliila dama Wood, Index Test., Suppl., p. 11 and figure, 1828. Oliva dama Mawe, Tryon, Man. Conch., Ser. 1, Vol. 5, p. 71, pi. 17, fig. 39, 1883. Olivelladama Mawe, DaU, NautUus, Vol. 32, p. 23, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Pleistocene: Magdalena Bay (DaU; Jordan); upper Quaternary at San Ignacio Lagoon (Jordan), both in Lower California, Mexico. Recent: Gulf of California to Mazatlan, Mexico. Olivella pedroana (Conrad) Plate 24, Figure 10 Slrephona pedroana Conrad, U. S. House of Representatives, House Document 129, p. 17, 1855; U. S. Pacific R. R. Repts., Vol. 5, p. 327, pi. 6, fig. 51, 18.56. Olivella intorta Carpenter, Proc. Zool. Soc. London for 1856, p. 207, Jan. 7, 1857; Cooper, Seventh Ann. Rept. Calif. State Mineralogist, p. 255, 1888; Keep, West Coast Shells, p. 42, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 212, pi. 19, fig. 9, 1S92; Arnold, Mem. Calif. Acad. Sci., Vol., 3, p. 220, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914; Martin, Vol. 9, p. 257, 1916; Moody, Vol. 10, p. 24, 1916. Olivella pedroana Conrad, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 221, but not all the synonymy, 1903; DaU, U. S. Geol. Surv., Prof. Paper 59, p. 32, pi. 6, fig. 1, 1909; Weaver, Wash. Geol. Surv., Bull. 15, p. 22, 1912; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 591, 594, 597, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 423, pi. 69, fig. 3, 1915; Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, pp. 30, 32, 1916; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 423, 1915; Martin, Vol. 9, p. 257, 1916; Nomland, Vol. 10, p. 221, 1917; DaU, U. S. Nat. Mus., BuU. 112, p. 85, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 162, 1927; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 251, 254, 1929. Type locality: Of pedroana, San Pedro, California, Recent. Miocene: Temblor formation, lower middle Miocene (Clark; Anderson and Martin); Montesano formation, middle Miocene of western Washington (Weaver); upper and lower San Pablo formation, middle California (Clark); Empire formation, Coos Bay, Oregon (DaU; Arnold and Hannibal; Howe); etc. Pliocene: Jacalitos, Etchegoin, Merced, Purisima, upper Sargent, etc., of middle California and Coalinga region (Arnold and Hannibal; Martin; Nomland; etc.); San Diego well (DaU); lower Pliocene of Elsmere Canyon, Los Angeles County (Arnold, 1907); lower Pliocene of Holser Canyon, Los Angeles County (English); etc. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 627 Pleistocene: Lower and upper San Pedro series of San Pedro region; Barlow's Ranch, near Ventura; foot of Twenty-sixth Street, San Diego (Arnold); Santa Barbara to San Diego (Cooper) ; near International Boundary Monument No. 258; Pacific Beach (Stephens); upper Pleistocene of San Quintin Bay and of San Ignacio Lagoon, Lower California, Mexico (Jordan, 1924, 1926); etc. Recent: Puget Sound to Cape San Lucas, Lower California, Mexico (Dall, 1921). This species has often been reported in the PUoeene and Pleistocene formations of Cahfornia, but the Recent shell is not so common in collections as might be expected. It is very similar to hcetica Carpenter, and the southern part of the living range may refer to the latter form. Olivella baetica Carpenter Olivella bstica Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; Gabb, Geol. Surv. Calif., Palato., Vol. 2, p. 75, 1868-9; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 71, pi. 17, figs. 28, 29, 1883; Cooper, Seventh Ann. Rept. Calif. State Mineralogist, p. 255, 1888. Olwella boetica Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 85, pi. 15, fig. 1, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 11, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 163, pi. 26, figs. 19, 19a, 22, 22a, 1917; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 2.50, 252, 1929. Olivella boetica diegensis T. S. Oldroyd, Nautilus, Vol. 34, p. 118, pi. 5, fig. 2, April, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 163, pi. 26, figs. 18, 18a, 1927. Olivella boetica mexieana T. S. Oldroyd, Nautilus, Vol. 34, p. 118, pi. 5, fig. 3, April, 1921; I. S. Oldroyd, op. cit., p. 163, pi. 26, figs. 21, 21o, 1927. Pliocene: Seven Mile Beach and Twelve Mile House, San Mateo County; San Diego well (Cooper). Pleistocene: Santa Barbara to San Diego (Cooper) ; lower San Pedro of Nob Hill cut, San Pedro (T. S. Old- royd); upper San Pedro horizon at San Pedro (T. S. Oldroyd, as var. mexieana and var. diegensis); Spanish Bight and near beach at Mexican boundary (Stephens) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Kodiak Island, Alaska, to Cape San Lucas, Lower California, Mexico (Dall, 1921). This species is more slender than biplicata. It appears to be larger in the northern part of its range. It may be only a variety of pedroana. Olivella baetica Carpenter variety porteri Dall Olivella (anazora Duel. var. ?) porteri Dall, Nautilus, Vol. 23, p. 133, April, 1910. Olivella porteri DaU, U. S. Nat. Mus., Bull. 112, p. 85, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 162, 1927. Type specimen: In the U. S. National Museum, No. 209,677. Type locality: San Diego, California, Recent. Pleistocene: Lower Quaternary at Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower Cali- fornia, Mexico (Jordan). Recent: Redondo, Los Angeles County, California, to Magdalena Bay, Lower California, Mexico (Dall, 1921). This is a slender form, often of a bluish-gray color with cloudings of liver color sometimes in zig-zag lines. It is probably a deeper water variety or variation of hcetica. Olivella gracilis (Broderip and Sowerby) Oliva gracilis Broderip and Sowerby, Zool. Journ., Vol. 4, p. 379, January, 1829; Reeve, Conch. Icon., Vol. 6, Oliva, pi. 20, fig. 46, 1850; not Oliva gracilis Lea, Contr. Geol., p. 182, pi. 6, fig. 196, 1833. Olivella gracilis Broderip and Sowerby, Tryon, Man. Conch., Ser. 1, Vol. 5, p. 70, pi. 16, fig. 26, 1883; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 453, 1926. Pliocene: Coyote Mountain, Imperial County (Hanna). Pleistocene: Coast of Oaxaca, Mexico (collected by R. H. Palmer). Recent: Gulf of California to Mazatlan, Mexico. 628 San Diego Society of Natural History [Memoirs This is an elongate species, the whorls steeply descending so that even the penulti- mate whorl is quite long. Tryon suggests that 0. tenuis (Marrat)i may have been based on a juvenile specimen of gracilis. Olivella inconspicua (C. B. Adams) Oliva inconspicua C. B. Adams, Ann. Lyceum Nat. Hist. New York, Vol. 5, p. 50 of the separate, 1852. Olivella inconspiciia C. B. Adams, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924. Pleislocene: Upper Quaternary at San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Gulf of California, Mexico, to Panama (Jordan). Family MARGINELLIDAE This family comprises a group of glossy-shelled species characterized chiefly by the presence of plications on the columella. The typical genus includes species with Voluta-\ike shells; but this type is connected by representatives of almost every inter- mediate stage to an extreme type with shortened or sunken spire and elongate, crescentic aperture, the posterior portion of which ascends to the apex of the shell. Some species belonging to the latter group are minute in size. Marginella, s. s., is distinguished from Valuta by its smaller size, by its usually thickened and frequently denticulate outer Up, and by the absence of the deep notch in the anterior canal. The MargineUidce are tropical and subtropical, few species venturing into tem- perate regions. The family dates back at least as far as the lower Eocene and is well represented in the European Tertiary. A number of species occur in the early and middle Tertiary of the western Atlantic coast and the West Indian regions, but the Tertiary of western North America has yielded only one or two species. The earliest definitely recognizable species of the MargineUidce reported from the Pacific coast is "Marginella" pacifica Dickerson, not Pease, which has been renamed instabilata by Hanna and is a Hyalina, probably of the Cystiscus group. It is thought to be Oligocene in age. No species of Marginella, s. s., has been definitely reported from California, either fossil or Recent. In order to determine the generic positions of the Pacific coast MargineUidce, it was necessary to consider the various names that have been commonly used for the different genera and minor divisions. The arrangement resulting from this brief review is outlined below: Genus Marginella Lamarck, 1799, type Voluta glabella Linnaeus. (+ Marginellarius Dumeril, 180Q; Marginellus Montfort, 1810; Phcenospira Hinds, 1844; Porcellana Gray, 1857, not Porcellana Martini, Conch. Cab., Vol. 1, p. 326, 1769 = Cyprcea Linnaeus; Pseudomarginella Maltzan, 1880, fide Cook, Proc. Malac. See. London, Vol. 15, pp. 3-5, 1922.) Spire elevated, shell typically of large size, outer lip thickened. Subgenus Marginella, s. s. Comparatively high spired, four strong plaits. Subgenus Glabella Swainson, 1840, type G. faba Linnaeus. {+ Faba Fischer, 1883.) With axial ribs. Subgenus Prunum Herrmamisen, 1852, type M. primum Gmelin. Lower spire; more elongate, subcylindric shape, deeper sinus. Subgenus Serrata Jousseaume, 1875, type M. serrata GaskoLn. Like Prunum but small, with thickened, serrated outer lip. Subgenus Eratoidea WeLnkauff, 1880, type M. margarita Kiener. Small, stout. I In Sowerby, Thes. Conch., Vol. 4, Olica, p. 32, pi. 22, fig. 385, 1870. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 629 Genus Persicula Schumacher, 1817, tj^pe P. variahilis Schumacher = V. persicula Linnseus. • (+ Gibberula Swainson, 1840; Cryptospira Hinds, 1844.) Spire very low or sunken; slaell usually of large size; outer lip thickened; aperture long, posterior end ascending toward the apex of the shell. Subgenus Persicula, s. s. Spire not elevated; outer lip arching over toward the apex of the shell. Subgenus BuUata Jousseaume, 1875, type M. bullata Bom. (+ Vohitella Swamson, 1820, not Perry, 1811, nor d'Orbigny; Egoueiia Jousseaume, 1875; G-ibbendina Monterosato, 1884; ? Leptegouana Woodrmg, 1928.) Spire low, with callus wash; callus pile on parietal wall. Subgenus Closia Gray, 1857, type AI. sarda Kiener. (+ ? Balanetta Jousseaume, 1875.) Spire invisible; outer lip extending to the apex of the shell; plications typicallj' concen- trated on the anterior portion of the columella. Genus Hyalina Schumacher, 1817, type H. pellucida Schumacher. (+ Volvarina Hinds, 1844; Granula Jousseaume, 1875.) Relatively small, spire low or covered; aperture long; outer lip simple. Subgenus Hyalina, s. s. Elongate; low spired. Subgenus Neovolvaria Fischer, 1883, type M. pallida Linnseus. Shape cyluidric ; outer lip flaring anteriorly. Subgenus Cystiscus Stimpson, 1865, tjqje Cystiscus capensis Stimpson, 1865, = Marginella cystiscus Redfield, 1870 (not M. capensis Dunker, 1848). Smaller, relatively broader. Subgenus Cijprceolina Cerulli-Irelli, 1911, type Cryptospira {Cyprceolina) clandestina Brocchi, 1814. . (+ Merovia Ball, 1921.) Small; spire covered by posterior part of outer lip; CZosta-shaped. The name Hyalina Schumacher is used for the very natural group of small, typically elongated shells with a simple outer lip or at least without the great thickening and denticulations that occur on the outer lip of some species belonging to Marginella and Persicula. The type of Hyalina has been said' to be indeterminable; but from a study of Martini's figure- and description, upon which H. pellucida was based, it is quite apparent what group Schumacher intended to name. Martini's figure is fairly good, considering the methods of reproduction available at the time and the small, unimposing character of the subject. Some ciuite recently published illustrations of supposed new species are less edifying than Martini's figures. Hyalina californica (TomUn) is certainly a typical Hyalina. In fact, this species greatly resembles Martini's figure of pellucida vSchumacher. Genus HYALINA Schumacher, 1817 Hyalina Schumacher, Ess. Nouv. Syst. Hab. Vers Test., p. 234, 1817; Tomlin, Proc. Malac. Soc. London, Vol. 12, p. 244, 1917. Type (by monotypy), H. pellucida Schumacher. Shell small; spire low or concealed by a callus wash or by the posterior margin of the aperture; outer lip simple or slightly thickened, without strong denticulations. Subgenus HYALINA, s. s. SheU elongate, oval; spire low, small, but clearly visible; columella somewhat constricted. ' Tomlin, Proc. Malac. Soc. London, Vol. 12, p. 288. 1917. ' Martini. Conch. Cab., Vol. 2, p. 108, pi. 42, fig. 426, 1773. 630 San Diego Society of Natural History [ Memoirs Hyalina (Hyalina) califomica (Tomlin) "Volvarina varia Sowerby," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; Keep, West Coast Shells, p. 43, 1888, 1892; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 176, 1894; and of Pacific coast authors before 1916, not of Sowerby, Proc. Zool. Soc. London for 1846, p. 97, 1846, and Thes. Conch., Vol. 1, p. 390, pi. 76, figs. 137-141, 1846, ^de Tomlin, Nautilus, Vol. 29, p. 138, April, 1916. "Marginella (Volvarina.) varia Sowerby," Arnold, Mem. Calif. Acad. Sci., Vol. 4, p. 222, pi. 4, fig. 9, 1903. Marginella {Hyalina) califomica Tomlin, Nautilus, Vol. 29, p. 138, 1916; Dall, Bull. 112, U. S. Nat. Mus., p. 85, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 165, 1927. Type specimen: In the Tomlin Collection, England. Type locality: California, Recent. Pleistocene: All lower and upper San Pedro localities in the vicinity of San Pedro, California; Pleistocene of Twenty-sixth Street, San Diego, California (Arnold, 1903); upper Pleistocene of San Quintin Bay, Lower California, Mexico (E. K. Jordan, 1926); Signal Hill (Oldroyd, as varia Sby.). Recent: San Pedro, California, to Puerto Libertad, Mexico (Dall, 1921), and the Galapagos (Stearns). This is the largest species of the family in the California region. It is recognizable by its size and its small but elevated spire. Subgenus CYSTISCUS Stimpson, 1865 Cystiscus Stimpson, Amer. Journ. Conch., Vol. 1, p. 55, 1865. Type (by monotypy), Cystiscus capensis Stimpson, ( = Marginella cystiscus Red- field), Amer. Journ. Conch., Vol. 6, p. 2, supplement pp. 226, 230, 1870 (not M. capensis Dunker, ex Dunker MS., Sudafrik. Moll., p. 125, pi. 6, fig. 21, 1848). Shell small, ovate, aperture hardly reaching spire, which is very low and inconspicuous. Geologic range: On Pacific coast of North America, Oligocene to Recent. Distribution: Tropical and warm temperate waters. This subgenus is a group intermediate between Hyalina with a definite spire and Cyprceolina with the spire concealed by the posterior margin of the elongated aperture. Stimson regarded the type of his genus sufficiently different anatomically to warrant a new family name ; but this opinion has not generally been followed by later authors. Hyalina (Cystiscus) jewettii (Carpenter) Plate 24, Figure 17 Marginella jewettii Carpenter, Proc. Zool. Soc. London for 1856, p. 207, Jan. 7, 1857; Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 43, pi. 12, fig. 57, 1883; Cooper, Seventh Ann. Rept. Calif. St. Mineralogist, p. 249, 1888; Dall, Trans. Wagner Free Inst. Sci., Vol. 3, pt. 1, p. 57, 1890; Keep, West Coast Shells, p. 43, fig. 23, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 212, pi. 19, fig. 6, 1892; Baker, Nautilus, Vol. 16, p. 40, 1902; .\rnold, Mem. Calif. Acad. Sci., Vol. 3, p. 221, 1903; Keep, West American Shells, p. 166, fig. 153, 1904; West American Shells, Rev. Ed., p. 142, fig. 114, 1911; E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 1 (41), 1919; Dall, Bull. 112, U. S. Nat. Mus., p. 85, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; T. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 164, 1927. Marginella jeivettii Carpenter, var. nanella T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, pp. 11, 24, pi. 2, fig. 8, January 16, 1925. Type specimens: In the U. S. National Museum. Type localities: Of jewettii, Santa Barbara, CaHfornia, Recent; of variety nanella, Nob Hill cut, San Pedro, California, Pleistocene. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 631 Pleistocene: Lower San Pedro series of Deadman Island and San Pedro (Arnold); lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd, as variety nanella); upper San Pedro series at Crawfish George's, San Pedro, and Deadman Island (Arnold); Chiton bed at Point Firmin, Los .\ngeles County (E. P. and E. M. Chace); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to San Martin Island, Lower California, Mexico (Baker). This species differs from H. caUfornica by its ovate or pyi-iform shape, its smaller size, and very low, inconspicuous spire. Recent specimens are very light gray, almost white. The number of plications on the columella varies from three to as many as eight, the small additional ones being added above the regular ones. The name naneUa apphes to specimens of jeioettii which have the more numerous plications on the inner lip. This character, by which nanella is distinguished, does not appear to have any systematic significance. The form with the extra plications occurs associated with the more normal form which has four to six plications, and intergrades perfectly Avith it. H. subtrigona is similar in general appearance but is smaller. Hyalina (Cystiscus) subtrigona (Carpenter) Marginella subtrigona Carpenter, Brit. Assn. Adv. Sci., Rept. for 1S63, pp. 537, 661, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 397, May, 1865; Tryon, Man. Conch., Ser. 1, Vol. 5, pp. 43, 198, pi. 12, fig. .55, 1883; T. S. Oldroyd, Nautilus, Vol. 28, p. 81, 1914; Dall, Bull. 112, U. S. Nat. Mus., p. 85, 1921; T. S. Oldroyd, Proc. r. S. Nat. Mus., Vol. 65, Art. 22 (No. 2.535), p. 11, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 164, 1927. Type specimen: In the British Museum. Type locality: Santa Barbara, California. Pleistocene: Lower San Pedro of Nob Hill cut, San Pedro; upper San Pedro of Signal Hill, Los Angeles County, (T. S. Oldroyd). Recent: Monterey to San Diego, California (Dall). This species much resembles H. jewettii but is considerably smaller. It has some- times as many as seven or eight columellar plaits, the posterior ones being very faint. Occasional specimens show a few weak denticulations on the inside of the outer lip, which is exceptional in this genus. H. regularis (Carpenter) is smaller, on the average, and is a narrower form. Hyalina (Cystiscus) regularis (Carpenter) Marginella regularis Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; .\nn. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 398, March, 1865; Baker, Nautilus, Vol. 16, p. 40, 1902; DaU, Bull. 112, U. S. Nat. Mus., p. 85, 1921, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 164, 1927. Similar to subtrigona but usually slightly smaller, with fewer, more widely spaced columellar pUcations and narrower shape. Average length about 2.5 mm. Type specimen: In the British Museum. Type locality: Santa Barbara, California. Pleistocene: San Pedro, California (in Oldroyd Collection at Stanford L'niversity) ; upper Pleistocene of San Quintin Bay, Lower California, Mexico (E. K. Jordan). Recent: Monterev to Gulf of California. 632 San Diego Society of Natural History [Memoirs Hyalina (Cystiscus) oldroydae (E. K. Jordan) Marginella oldroydx E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 250, pi. 25, fig. 7, 1926. Type specimen: At the California Academy of Sciences, No. 1846. Type locality: San Quintin Bay, Lower California, Mexico; upper Pleistocene. Pleistocene: At the type locality. This species or variety is related to regularis (Carpenter) , but is evenly ovate instead of pyriform, the greatest width occurring just posterior to the middle of the shell. The evenly ovate form is characteristic. The spire does not seem to be glazed over. There are about a dozen specimens in the collection of the California Academy of Sciences, all from the type locality. Hyalina (Cystiscus) instabilata (Hanna) Marginella pacifica Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 7, p. 178, pi. 31, fig. 2, 1917, not M. pacifica Pease, 1868. Marginella instabilata Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 170, 1924, new name for M. pacifica Dickerson. Type specimen: At the California Academy of Sciences, San Francisco. Type locality: Near Vader, Lewis County, Washington; Oligocene. OUgocene: At the type locality. The shell characters of this small species place it in Cystiscus. There are five oblique plications, including the one on the lower, obliquely-truncated margin of the columella. On the inside of the outer lip there are six small lirations. The suture between the whorls of the low spire is not clearly marked. Dickerson reported the species abun- dant in the Molopophorus lincolnensis zone, Lincoln horizon of the lower Oligocene, at the type locality in Washington. Subgenus CYPRAEOLINA Cerulli-IreUi, 1911 Cyprxolina S. CerruUi-Irelli, Palseontographia Italica, Memorie di Paleontologia, Vol. 17, p. 231, pi. 21, figs. 9-14, 1911, new subgenus of Cryptospira Hinds, 1844. Merovia Dall, BuU. 112, U. S. Nat. Mus., p. 86, 1921, monotype, Volutella pyrijormis Carpenter, figured by Tryon, Man. Conch., Vol. 5, pi. 12, fig. 65, 1883. Type (by monotypy), Cryptospira (Cyprceolina) clandestina Brocchi. Shell small, aperture lengthened posteriorly, margin covering the apex of the shell. Hyalina (Cypraeolina) pyriformis (Carpenter) Volutella pyriformis Carpenter, Journ. Conchyl., Ser. 3, Vol. 5, p. 148, 1865. Merovia pyriformis Carpenter, Dall, Bull. 112, U. S. Nat. Mus., p. 86, 1921. "Cyprxolina margaritula Carpenter," T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 11, 1925. Marginella pyriformis Carpenter, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Cyprseolina pyriformis Carpenter, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 166, 1927. Type specimen: In the U. S. National Museum (?). Type locality: San Diego, California. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (E. K. Jordan); Pleistocene of San Pedro (T. S. Oldroyd coll.); lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd, as C. margaritula). Recent: Peril Strait, Alaska, to Mazatlan, Mexico (Dall, 1921). Volume I] Pliocene and Pleistocene Mollusca of California 633 This species is the type of Merovia Dall, which is clearly a synonym of Cyprceolina Cerrulli-Irelli. It is larger and a little less pyriform than H. clandesiina (Brocchi), the type of Cyprwolina. It is similar to H. margarilula (Carpenter), but that species differs in having a more effuse or dilated anterior portion of the aperture. The specimens at Stanford University identified as margaritula by Mr. T. S. Oldroyd are pyriformis. Family VOLUTIDAE Shell turreted, apex papillary, aperture notched in front; columella oljliquely plaited; with or without an operculum, which, when present, has a terminal or subterminal nucleus. The Mitridce differ in not having a papillary apex and in having the columellar plica- tions heavier posteriorly. Genus PSEPHAEA Crosse, 1871 Psephasa Crosse, Journ. de Coiichyl., Vol. 19 (Ser. 3, Vol. 11), p. 302, October, 1871, only species Valuta concinna Broderip; Tryon, Man. Conch., Ser. 1, Vol. 4, p. 98, 1882; Fischer, Man. Conchyl., p. 607, 1883; Cossmann, Ess. Paleo. Comp., Vol. 3, p. 145, 1899. Miopleiona Dall, Smithsonian Misc. Coll., Vol. .50, Pt. 1, p. 11, March 7, 1907; U. S. Geol. Surv., Prof. Paper 59, p. 35, April 2, 1909. Type (by monotypy), Voluta concinna Broderip, Proc. Zool. Soc. London, Pt. 4, p. 43, 1836; figured by Reeve, Conch. Icon., Vol. 6, Voluta, pi. 21, fig. 53, 1849; also figured by Crosse, op. cit., pi. 12, fig. 7, 1871; Japan, Recent. Shell elongate, spire produced; sculpture consistmg of axial folds, which may be accentuated toward the upper part of the whorl in such a way as to produce a shouldered effect, also of very fine growth lines; aperture large, elongate; outer hp sometimes a Kttle thickened and shghtly flar- ing, hmer Up with a wide, thin callus deposit; columella tapering, with two subdued, very oblique plications. Geologic range: Eocene to Recent. Distrihution: Warm and temperate waters. Miopleiona Dall' differs so little from Psephcea Crosse that the former must be con- sidered a synonym. Psephcea appears to be generically distinct from Voluta Linnseus, having a much higher spire and two columellar plications, one of moderate size and one small, instead of four. Psephaea prevostiana (Crosse) Plate 27, Figure 9 ? "Voluta lyriformis Vigors," Iviener, Spec. Gen. Icon. Coq. Viv., Vol. 3, "Volute," p. .35, pi. 42, fig. 2, 1839; ? not "Mitra" lyriformis Swainson, Zool. lUust., Vol. 1, pi. 54, 1821. Valuta ■prevostiana Crosse, Journ. Conchyl., Ser. 3, Vol. 18, p. 165, 1878; Vol. 19, p. 41, pi. 1, pi. 2, fig. 1, 1879; Vol. 27, p. 42, pi. 1, 1887; Sowerby, Ann. Mag. Nat. Hist., Ser. 8, Vol. 14, p. 81, 1914. "Valuta megaspira Sowerby," Tryon, Man. Conch., Vol. 4, p. 95, in part only, pi. 30, fig. 132, 1882, not of Sowerby, Thes. Conch., Vol. 1, p. 208, pi. 48, figs. 31, 32, 1844, nor of Yokoyama, Journ. Faculty Sci., Imper. Univ. Tokyo, Sect. 2, Vol. 1, p. 316, 1926. ]'aluta megaspira, var. prevostiana Crosse, Sowerby, Thes. Conch., Vol. 5, p. 298, pi. 573, fig. 144, 1887. Type locality: Japan. Recent: Japanese region. ^ Dall designated M. indurata (Conrad) as type. 634 San Diego Society of Natural History [ Memoirs This high-spired, rather thin-shelled species lacks the shoulders on the axial ribs which are present on P. concinna, the genotype of Psephcea, but it is closely related. A comparison of specimens of typical prevostiana from the Japanese region with fossil specimens of the variety oregonensis (Dall) shows that the only difference is that the fossil variety has somewhat fewer and slightly protractively sloping axial ribs. The Recent typical variety and the fossil variety are figured side by side on plate 27. In the collection at Stanford University there is a large Recent specimen of typical prevostiana from Japan which measures 140 mm. in length and 72 mm. in width. Psephaea prevostiana (Crosse) variety oregonensis (Dall) Plate 27, Figures 6, 10 "Rostellaria indurala Conrad," in part, of authors prior to 1907. Miopleiona oregonensis Dall, Smithsonian Misc. Coll., Vol. 50, Pt. 1, p. 11, March 7, 1907; Arnold, Proc. U. S. Nat. Mus., Vol. 34, pi. 37, fig. 2, 1908; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 35, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 590, 1913; J. P. Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, p. 143, 1919; Howe, Univ. Calif. Publ. Geol., Vol. 14, table opp. p. 93, 1922. Type specimen: In the IT. S. National Museum, No. 153,894. Type locality: Coos Bay, Oregon; Miocene. Miocene: Empire formation, upper Miocene of Coos Bay, Oregon (Dall, 1909; also reported from "Tillamook Head, Washington," which may be an error). Pliocene: Coos conglomerate, Coos Bay, Oregon (Howe); Wildcat formation of Humboldt County (J. P. Smith); Eel River beds, northern California (coll. by Harold Hannibal); Pliocene of Ano Nuevo Point, San Mateo County (coll. by R. Arnold) ; about 12 miles south of Gary, Santa Barbara County (Arnold); "Fernando" of Fugler's Point, Santa Barbara County (Carson); San Diego (coll. Los Angeles Museum). This variety differs from the typical form only in the slope of the axial ribs, which are perhaps fewer in number. P. indurata (Conrad), the Oligocene and Miocene species, is specifically distinct. H. G. Schenck states that there is another, as yet undescribed, species in the Oregonian Oligocene. Family MITRIDAE Shell elongate, spire produced, with an acute apex; columella with plications that are stronger posteriorly. Genus MITRA Martyn, 1784 Mitra Martyn, Univ. Conch., Vol. 1, explanatory table and pi. 19, 1784; Dall, Proc. U. S. Nat. Mus., Vol. 29, p. 428, 1905; Woodring, Carnegie Inst., Publ. No. 385, p. 242, 1928. Type (by subsequent designation, Dall, 1905), Mitra tessellata Martyn, op. cit., pi. 19, 1784; figured also by Reeve, Conch. Icon., Vol. 2, Mitra, pi. 2, fig. 10, 1844; also by Tryon, Man. Conch., Ser. 1, Vol. 4, p. 132, pi. 38, fig. 139, 1882; China, Recent. In the Tenth Edition of the Systema Naturae (p. 732), Linnseus appears to have used Mitra as a subgenus of Voluta with the species episcopalis and papalis, but the in- consistencies in Linnaeus' treatment of such minor subdivisions have led authors to dis- regard his minor gi-oup names. If the Linnaean Mitra is used, the type is M. episcopalis Linnseus, as that species was cited by Children^ in 1823. The type of Mitra Martyn is a high-spired form having axial and spiral sculpture in a cancellated pattern, which sometimes appears like regularly arranged pits or puncta- ' Quarterly Journ. Sci., Lit., and the Arts, p. 62, October. 1823. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 635 tions. The species catalogued below, while not typical, are not subgenerically different from Mitra, s. s. They do not seem to be closer to the subgenus StrigateUa than to Mitra, s. s. The type of StrigateUa is Mitra zebra Lamarck, a smooth, rather short species much like a Pyrene. StrigateUa should not be used in more than a subgeneric sense, for while some of the short, pyreniform, thick-lipped species belonging clearly to StrigateUa are very different from Mitra, s. s., there are several intermediate species, and there is no natural break between the two. Mitra idae Melvill "Mitra maura Swainson," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; Tryon, Man. Conch., Ser. 1 , Vol. 4, p. 121, in part, not pi. 36, fig. 67, 1882; Cooper, Seventh Ann. Rept. Calif. State Mineralogist, p. 257, 1888; Keep, West Coast Shells, p. 42, fig. 22, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 222, 1903 ; not Mitra maura (Swainson, MS.) Broderip, Proc. Zool. Soc. London, Pt. 3, p. 193, April, 1836, = M. orientalis Gray, 1834. Mitraida; Melvill, The ConchologLst, Vol. 2, p. 140, pi. 1, fig. 6, June 24, 1893; Williamson, Proc. Biol. Soe. Washington, Vol. 19, p. 195, figs. 1-5, 1906; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 170, 1927. Mitra idx "Dall," English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914. StrigateUa {Atrimitra) idx Melvill, Dall, U. S. Nat. Mus., Bull. 112, p. 86, 1921. Tijpe specimen: In the collection of Sir J. R. LeB. Tomlin, St. Leonards-on-Sea, England. Type locality: Point Loma, San Diego County, California; Recent. Pliocene: Lower Pliocene of Elsmere Canyon, Los Angeles County (English) ; lower part of the upper Pliocene at Fifth and Hope Streets, Los Angeles, California. Pleistocene: Lower San Pedro series at San Pedro and upper San Pedro series at Deadman Island, San Pedro, and Crawfish George's, Los Angeles County (Arnold); upper Pleistocene of San Diego (in the Old- royd Collection at Stanford University). Recent: Farallone Islands to San Diego and Cortez Bank, California. This species is the North American analogue of the Peruvian Mitra orientalis Gray' (-1- M. maura Swainson MS., Broderip). It is smaller and the whorls are less ventricose than the southern species. M. fultoni E. A. Smith has a more attenuated spire and the spiral punctation is more distant, deeper , and wider. Mitra idae Melvill variety montereyi Berry Mitra montereyi Berry, Proc. Malac. Soc. London, Vol. 14, p. 31, text figures 1-4, 1920. StrigateUa {Atrimitra) idse montereyensis Berry, Dall, U. S. Nat. Mus., BuU. 112, p. 86, 1921. Mitra idx montereyensis Berry, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, j). 171, 1927. StrigateUa {Atrimitra) idea montereyensis Berry, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type specimen: In the collection of S. S. Berry, Redlands, California. Type locality : Twelve fathoms off Del Monte, Monterey Bay, California. Pliocene: "Lower Pico," middle Pliocene near Ventura (Waterfall). Recent: Monterey to San Diego, California (Dall). This form is very similar to the typical form of idop but is larger and more robust. The lower Pliocene record of idoe (Elsmere Canyon, fide English) may refer to this variety. ' In Griffith's Cuvier, pi. 40, fig. 5, 1834. 636 San Diego Society of Natural History [ Memoirs Mitra fultoni E. A. Smith Mitrafultoni E. A. Smith, Ann. Mag. Nat. Hist., Ser. 6, Vol. 9, p. 256, text figure, 1892; Williamson, Bull. So. Calif. Acad. Sci., Vol. 4, p. 123, 1905; Proc. Biol. See. Washington, Vol. 19, p. 197, text fig. 6, 1906. Type locality: Point Abreojos, Lower California, Mexico; Recent. Pleistocene: Upper Pleistocene near Santa Monica (in the Oldroyd Collection at Stanford University). Recent: Lower California, Mexico, southward. This species is rather slender for the orientaUs group and can be distinguished by a slight shoulder on the whorls and some minor differences in sculpture. Mitra catalinae (Dall) Plate 28, Figure 4 Strigatella (Atrimitra) calalinse Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 308, Augu.st 30, 1919; U. S. Nat. Mus., Bull. 112, p. 86, 1921. Strigatella catalinse Dall, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Milra catalinx Dall, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 169, 1927. Type specimen: In the U. S. National Museum, No. 219,648. Type locality: San Pedro, California; Recent. Pliocene: S. D. S. N. H. locality 217b, middle Pliocene of Holser Canyon, Los Angeles County (H. R. G.). Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Crescent City to San Diego, California (Dall, 1921). The general appearance of the shell of this species suggests that it may be the young of Mitra ida Melvill, but there are not sufficient specimens on hand to decide the matter. Section Tiara Swainson, 1831 Tiara Swainson, Zool. Illustr., Ser. 2, Vol. 2, expl. pi. 50 {Mitrinx, pi. 5), 1831; Woodring, Carnegie Inst., Publ. No. 385, p. 242, 1928; not Thiara Bolten, Mus. Boltenianum, p. 190, 1798, misspelled "Tiara" by Herrmannsen, Ind. Gen. Malac, Vol. 2, p. 576, 1849; not Thiara Menke, Syn. Meth. Moll., Ed. 2, p. 42, 1830, misspelled "Tiara" by Agassiz, Nomen. Zool., Moll., p. 90, 1846. Caneilla Swainson, Treat. Malac, p. 320, 1840; Herrmannsen, Ind. Gen. Malac, Vol. 1, p. 166, 1846, Tiara Isabella Swainson designated type. Type (by subsequent designation, Herrmannsen, 1849), Tiara isabella Swainson, figured by Reeve, Conch. Icon., Vol. 2, Mitra, pi. 6, fig. 42, 1844; China, Recent. Shell slender, like that of Mitra, s. s., but with strong spiral cords; columella with four or five plaits increasing in size posteriorly. If this subdivision is based primarily on sculpture it is doubtful if it should be con- sidered a natural section. There seem to be many species, which in sculptural characters, are intermediate between those with strong spirals and those with weak or obsolete ones. Some species, such as Mitra titan Gabb' of the Miocene of Santo Domingo, have strong spiral sculpture when young but lose all or nearly all of it when attaining the adult stage. Fusiynitra Conrad- is a very similar group of slender, spirally sculptured species, of which the above mentioned Mitra titan Gabb is probably a member. It may be a syno- nym of Tiara Swainson. Mitra mellingtoni Conrad is the type of Fusimitra, not M. ceUulifera Conrad, which was not included in Conrad's original list of species. Vromitra Bellardi^ has been used for some of the axially plicate, fusiform species. > Trans. Amer. Philos. Soc, Vol. 15, p. 220. 1873; figured by Pilsbry, Proc. Acad. Nat. Sci. Phila. for 1921, p. 340, pi. 24, figs. 1, 2, January 30, 1922. Mitra sym-metrica Gabb, op. cit., is the young stage. 'Proc. Acad. Nat. Sci. Phila., Vol. 7, p. 261. 1855. Tryon, Fisher. Cossmann and Dall have dated Fusimitra Conrad from 1865 (Amer. Journ. Conch., Vol. 1, p. 25) and misinterpreted its characters. > Mem. R. Accad. del. Sci. Torino, Ser. 2, Vol. 38, p. 277, 1887. Type, Uromitra anlegressa Bellardi. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 637 Mitra sulcata Swainson Mitra sulcata Swainson, Sowerby, Cat. Shells Tankerville, Appendix, p. 26, 1825; Reeve, Conch. Icon., Vol. 2, Mitra, pi. 22, fig. 176, 1844; Tryon, Man. Conch., Ser. 1, Vol. 4, p. 139 in part, pi. 40, fig. 171, 1882; Dall, Proo. U. S. Nat. Mus., Vol. 37, p. 212, 1909; Hanna, Proo. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 450, 1926. Tiara sulcata Swainson, Zool. Illustr., Ser. 2, Vol. 2, pi. 5, figs. 1, la, 1831. Shell small, subcorneal, transversely sulcated, white varied with gray, throat brown; lip crenated (Swainson, in Sowerby, 1825). Pliocene: Coyote Mountain, Imperial County (Hanna). Recent: West Coast of Central America southward to Ecuador (Dall). The biconoidal shape and strong spiral sculpture distinguish this species from all the preceding ones. Family FASCIOLARIIDAE Genus FASCIOLARIA Lamarck, 1799 Fasdolaria Lamarck, Mem. Soc. Hist. Nat. Paris, Ser. 1, Vol. 1, p. 73, 1799; Woodring, Carnegie Inst., Publ. No. 385, p. 255, 1928. Type (by monotypy), Murex tulipa Linnaeus, figured by Reeve, Conch. Icon., Vol. 4, Fasdolaria, pi. 4, fig. 9, 1847; Caribbean region; Recent. Shell stout, fusiform, sometimes very large; aperture long, wide; colmnella with one to three low, oblique folds; interior of outer lip finely Urate; anterior canal of moderate length, narrow, oblique ; sculpture of spiral cords and grooves and with or without axial ribs or nodes on the shoulder. The type of Fasdolaria lacks the strong nodes on the shoulder. The earliest species of the genus in the Caribbean region are of lower Miocene age, according to Woodring. The Pacific coast Eocene species attributed to this genus probably do not belong there. Fasciolaria princeps Sowerby Fasdolaria princeps Sowerby, Cat. Shells Tankerville, Appendi.\, p. 16, 1825; ICiener, Spec. G6n. Icon. Coq. Viv., Vol. 6, Fasciolaire, p. 6, pis. 12, 13, 1840; Reeve, Conch. Icon., Vol. 4, Fasciolaria, pi. 1, fig. 3, 1847; Tryon, Man. Conch., Ser. 1, Vol. 3, p. 75, pi. 60, fig. 11, 1881; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 212, 1909; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 448, 1926; Hanna and Hertlein, Vol. 16, pp. 143, 150, 1927. Pliocene: Coyote Mountain, Imperial County (Hanna); Santa Antonita Point and Ceralbo Island, Gulf of California, Mexico (Hanna and Hertlein). ReceTit: Magdalena Bay, Lower California, and Gulf of California, Mexico, south to Panama, Peru, and Galapagos Islands. Fasdolaria princeps is a well-known, large, southern shell with spiral riblets and a somewhat carinated or shouldered whorl. It lacks the prominent nodes of F. granosa Broderip. Fasciolaria granosa Broderip Fasdolaria granosa Broderip, Proc. Zool. Soc. London for 1832, p. 32, 1832; Reeve, Conch. Icon., Vol. 4, Fasdolaria, pi. 3, fig. 6, 1847; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 212, 1909. Pldslocene: Coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: West Me.xico to Panama and Peru (Dall). This is a dark-colored species with prominent nodes on the shoulder of the whorls. 638 San Diego Society of Natural History [ Memoirs Genus FUSINUS Rafinesque, 1815 Fusus Bruguiere, Ency. Meth., Vers, p. 15, 1789; Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 73, 1799; Grabau, Smithsonian Misc. Coll., Vol. 44, p. 89, etc., 1904; Dall, Journ. Conch., Vol. 11, pp. 289-297, 1906; DoUfus, Rev. Crit. de Paleozool. for July, 1908, p. 219; Cossmann, Ess. Paleo. Comp., Vol. 8, p. 226, 1909; not Fusus Helbling, Abh. Privatges. Naturg., Vol. 4, pp. 116-120, 1779, ^te Dall, 1906. Fusimis Rafinesque, Analyse de la Nature, p. 145, 1815, new name for Fusus Lamarck; Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 36-39, 1909; Woodring, Carnegie Inst., Publ. No. 385, p. 256, 1928. Type (by monotypy, Lamarck, 1799, — first species assigned to the genus, which was originally described without species), Murex colus Linnseus; figured by Reeve, Conch. Icon., Vol. 4, Fusus, pi. 3, fig. 11, 1847; Indo-Pacific ; Recent. Shell large, slender, spindle-shaped, with a long, nearly straight, open anterior canal; aperture ovate, outer lip Urate withm, parietal wall with callus deposit; sculpture of spiral threads or cords, usually prominent, and of low axial folds or ribs. This genus has been frequently used improperly for species which are not closely related; likewise, the subdivisions have not been carefully applied. For a discussion of the taxonomy, consult the papers by Dall, Dollfus, and Woodring referred to above. Section Fusinus, s. s. Shell very elongate, spindle-shaped, with a long, nearly straight, partially closed, anterior canal, and a well-defined lip-like callus on the body whorl. The following species, while somewhat shorter and with a heavier anterior canal than the type species of Fusinus, appears to be more closely related to the typical section than to F. barbarensis and its allies. Fusinus dupetit-thouarsi (Kiener) Fusus dupetit-thouarsi Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 5, Fuseau, p. 15, pi. 11, 1840; Reeve, Conch. Icon., Vol. 4, Fusus, pi. 2, fig. 9, 1847; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924; Hanna and Hertlein Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. Type specimen: In the Natural History Museum, Paris ? Type locality: Coasts of California, probably meaning Lower California, Mexico. Pliocene: Santa Antonita Point, Gulf of California, Me.xico (Hanna and Hertlein). Pleistocene: Upj5er Quaternary of San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Lower California and west coast of Me,\ico, Galapagos (Reeve). Fusinus dupetit-thouarsi (Kiener) has a high spire, a long canal, and well-defined spiral sculpture; but the axial ribs are poorly defined or absent. Kiener 's figure shows a slight carination on about the middle of the whorls and practically no evidence of axial ribs. Some specimens from Lower California have more or less definite axial folds, but they may not belong to this species. The extent of variation is as yet unknown. Reeve's figure shows axial folds. His specimen came from the Galapagos Islands. Section Gracilipurpura Jousseaume, 1880 Gracilipurpura Jousseaume, Le Naturahste, An. 2, p. 335, Dec. 15, 1880. Barbarofusus Grabau and Shimer, North American Inde.K Fossils, Vol. 1, p. 775, 1909, type (by original designation), Fusus barbarensis Trask. Type (by original designation), Fiisus strigosus Lamarck, figured as Fusus rostratus Olivi by Reeve, Conch. Icon., Vol. 4, Fusus, pi. 14, species 55, Dec, 1847; Mediterranean. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 639 Shell loosely coiled, less elongate than typical Fusinus, with shorter, more widely open anterior canal and less clearly delimited parietal callus. The southern California species of the section Gracilipurpura can be tabulated according to characters as follows: Shell thin, elongate, without prominent revolving brown lines Large, whitish F. barbarensis Small, purplish when fresh F. arnoldi Shell heavy, relatively short, with brown revolving lines when fresh Medium in size, anterior canal moderately short, axial sculpture very strong F. kobelti Small, anterior canal shorter and axial sculpture not as strong as in F. kobelti F. monksa; Fusinus barbarensis (Trask) Plate 27, Figure 11 Fust(s barbarensis Trask, Proc. Calif. Acad. Sci., Vol. 1, p. 41, 1855; Cooper, Seventh Ann. Kept. Calif. State Mineralo- gist, p. 240, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 224, pi. 4, fig. 15, 1903; English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914. "FusTMS corpulentus Conrad," Cooper, Calif. State Mining Bureau, Bull. No. 4, Pt. 3, p. 26, 1894, not of Conrad, 1849. Fusinus barbarensis Trask, Dall, U. S. Nat. Mus., Bull. 112, p. 88, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 177, 1927. Type specimen: In the California Academy of Sciences. Type locality: Santa Barbara, California. Pliocene: Elsmere, Holser, and Pico canyons, Los Angeles County (English); S. D. S. N. H. locality 263, middle Pliocene between Pico Canyon and Fernando Pass, Los Angeles County (H. R. G.). Pleistocene: "Pliocene" of Deadman Island, common; rare in the lower San Pedro series of Deadman Island and in the upper San Pedro of Deadman Island, San Pedro, and Crawfish George's, Los Angeles County (Arnold); Santa Barbara (Trask; Cooper). Recent: Heceta Bank, Oregon, to San Diego, California (Dall, 1921). This species is thin shelled, slender, has a long spire, clear-cut spiral sculpture crossing the axial ribs, and a long anterior canal. Fusinus barbarensis (Trask) variety arnoldi (Cossmann) Fusu^ rugosus Trask, Proc. Calif. Acad. Sci., Vol. 1, p. 41, 1855; Cooper, Seventh Ann. Rept. Calif. State Mineralogist, p. 241, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 226, pi. 4, fig. 7, 1903; not Fusus rugosus Lamarck, 1804. Fasus arnoldi Cossmann, Rev. Paleozool., Vol. 7, p. 215, 1903, new name for F. rugosus Trask, not Lamarck; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 166, 1924. Fusinus traski DaU, Nautilus, Vol. 29, p. 54, 1915, new name for F. rugosus Trask, not Lamarck; DaU, U. S. Nat. Mus., Bull. 112, p. 88, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 176, pi. 9, fig. 4, 1927. Type specimen: At the California Academy of Sciences. Type locality: San Pedro, CaUfornia. Pleistocene: "Found only in the lower San Pedro series of Deadman Island," rather rare (Arnold); Santa Barbara (Cooper). Recent: San Pedro to San Diego, California (Dall, 1921). 640 San Diego Society of Natural History [ Memoirs This variety is smaller and sometimes has stronger axial ribs than typical bar- harensis. When fresh it is of a purplish color but fossil specimens are hard to distinguish from the young of the typical variety. Cossmann renamed Trask's homonym and Hanna called attention to it. Ball's name is superfluous. Fusinus kobelti (Dall) Fxtsm kobelti Dall, Proc. Calif. Acad. Sci., Vol. 7, p. 54, 1877; Proc. U. S. Nat. Mus., Vol. 14, p. 177, pi. 6, fig. 4, 1891. Fusinus kobelli Dall, U. S. Nat. Mus., Bull. 112, p. 88, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 178, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type specimen: In the U. S. National Museum. Type locality: Monterey, California. Pleistocene: "Saugus" formation near Ventura (Waterfall). Recent: Monterey to Catalina Island, California (DaU) . Fusinus kobelti Dall is a relatively small, strongly axially sculptured species with a shorter spire and anterior canal than F. barbarensis. It is also much heavier and not a typical Gracilipurpura. Fusinus kobelti (Dall) variety monksae (Dall) Fusus rohustus Trask, Proc. Calif. Acad. Sci., Vol. 1, p. 41, 1855; Cooper, Seventh Ann. Rept. Calif. State Mineralo- gist, p. 241, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 226, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908; not F. robustus Beyrich, 1853 . "Fusiis kobelti Dall," Cooper, op. cit., p. 240, in part, not of Dall, fide Arnold, 1903; also of Delos Arnold, Nautilus, Vol. 10, p. 142, 1897. FvMnm monksx Dall; Nautilus, Vol. 29, p. 55, 1915; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; Dall, U. S. Nat. Mus., Bull. 112, p. 88, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 11, 1925; Water- fall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pliocene: "Pico" near Ventura (Waterfall); Bath-house Beach, Santa Barbara (Arnold; also Berry, reported questionably) . Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd) ; "Found only in the upper San Pedro series; rather common at Old San Pedro" (Arnold); upper San Pedro of Santa Monica, Los Angeles County (Oldroyd Collection at Stanford University). Recent: Banks Island, British Columbia, to Pequena Bay, Lower California, Mexico (Dall, 1921). This shell appears to average smaller than kobelti and has a shorter anterior canal, in fact the shortest canal of all the shells here placed in Gracilipurpura. The axial ribs are not as strong on variety monksce as on the typical variety of kobelti and on some speci- mens of monksce the spiral cords are more prominent than the axial ribs. Both typical kobelti and the variety monksce have distinct brown spiral lines when fresh. There has been considerable confusion among the shells of the Gracilipurpura group and misidentifications are common in most collections. If F. kobelti is correctly inter- preted here, there should be no difficulty in distinguishing it from the large, thin shelled, elongate typical F. barbarensis ^ > Through the courtesy of Mr. Howard R. Hill, the collections of shells of this group in the Los Angeles Museum have been available for study. Mr. George Willett'e collection has likewise been available, in which the four shells discussed above appear to have been correctly segregated. Volume 1 1 PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 641 Fusinus coalingensis (Nomland) Chrysodonms coalingensis Nomland, Univ. Calif. Publ. Geol., Vol. 9, no. 14, p. 205, pi. 10, fig. 3, February 24, 1916. Type specimen: In the collection at the University of California. Type locality: Jacalitos formation of Coalinga region; lower Pliocene. Pliocene: At the type locality. This species, as figured, has a long canal like that of Fusinus barbarensis. Fusinus coosensis Dall' and F. empireensis Anderson and Martin,- both from the Empire formation of Coos Bay, Oregon, appear to represent one or two eroded species of the section Gracili purpura. F. fabulator Nomland, ^ from the Santa Margarita, upper Miocene, of California, is also probably a member of the Gracilipurpura group. Section Harfordia Dall, 1921 Harfordia Dall, U. S. Nat. Mus., Bull. 112, p. 88, 1921. Type (by monotypy), Fusinus harfordii (Stearns), Proc. Calif. Acad. Sci., Vol. 5, p. 79, 1873, separate issued as Conchological Memoranda No. 7, p. 1, August, 1871; figured by Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 178, pi. 6, fig. 6, 1891, Coast of Mendo- cino County, California; Recent. Shell Buccinoid in shape but with the anterior canal produced; shell shorter than in typical Fusinus, wdth much shorter anterior canal. Dall placed Fusinus luteopictus in the typical section of Fusinus and Fusinus har- fordii (Stearns) in a new section Harfordia. The former is very different from the long, spindle-shaped species with very long anterior canals which are here considered Fusinus, sensu siricto; but it is very similar to F. harfordii (Stearns), the monotype of Harfordia Dall. The differences may be not more than specific. Fusinus luteopictus (Dall) F«SMs luteopictus Dall, Proc. Calif. Acad. Sci., Vol. 7, p. 3, 1877; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 217, pi. 20, fig. 1, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 225, 1903. "Fms«s ambustus Gould," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 664, 1864, in part, not of Gould, fide Dall. "Fusys geniculus Conrad," Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 71, 1868-9, in part, not the synonymy, fide Dall. Fusinus bdeopictvs Dall, U. S. Nat. Mus., Bull. 112, p. 88, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 179, 1927. Type specimen: In the U. S. National Museum. Type locality: Monterey, California; Recent. Pleistocene: Lower San Pedro series of Deadman Island, "rare"; common in upper San Pedro series at Craw- fish George's, but rare at San Pedro, Deadman Island, and Los Ceritos (Arnold). Recent: Monterey, California, to Gulf of Cahfornia, Mexico (Dall, 1921). This species has a short anterior canal very unlike that of typical Fusinus. It has fold-like axial ribs crossed by strong, raised, strap-like spiral cords. 1 U. S. Geol. Surv., Prof. Paper 59, p. 41, pi. 2, fig. 1, 1909. ' Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. S4. pi. 5, fig. 7, 1914. ' Univ. Calif. Publ. Geol., Vol. 10, p. 309, pi. 20, fig. 10, 1917. 642 San Diego Society of Natural History [Memoirs Family NEPTUNEIDAE A number of genera in this family intergrade with the Muricidoe and the Buccinidce, and the close relationship of the Fasciolariidce is also clear. Genus KELLETIA Bayle in Fischer, 1884 Kelletia Bayle, Fischer, Man. Conchyl., fasc. 7, p. 625, 1884, only species Siphonalia kelletii Forbes; Cossmann, Ess. Pal^o. Comp., Vol. 4, 1901. Roperia Dall, Nautilus, Vol. 12, p. 5, May, 1898, as section of Fusus, type F. roperi Dall. Type (by monotypy), Kelletia kelletii (Forbes), southern California; Recent. Shell of medium size or large, heavy, spire and aperture of about equal length; sculpture con- sisting of spiral striations or riblets and prominent nodosities on the shoulder of the whorls; aperture ovate, with a moderate anterior canal; outer lip not thickened, with lirations within; inner hp with a sharply delimited callus deposit, smooth ; columella long, somewhat sinuous, tapering toward the end; siphonal fasciole large, with an umbilical chmk or notch between it and the end of the colu- mella; operculum with an apical nucleus; epidermis absent or a mere film. The type species attains a length of 145 mm. and a breadth of 75 mm. Subgenus KELLETIA, s. s. Shell large, spiral sculpture differentiated into primary, secondary, tertiary, and even quarternary revolving riblets. Geologic range: Lower middle Miocene to Recent. Distribution: Warm and temperate north (and south ?) Pacific Ocean. Penion Fischer (op. cit., p. 625, type "Siphonalia^' dilatata Quoy) differs in the tabula- tion or carination on the upper part of the whorls. It might well be considered a sub- genus or section of Kelletia. Austrofusus Kobelt appears to approach Cantharus and Siphonalia in form. Searlesia Harmer differs from typical Kelletia in its smaller size and more simple spiral sculpture. It has a more northern habitat than the larger, typical Kelletias. Kelletia is closely related to Cantharus. Kelletia (Kelletia) kelletii (Forbes) Plate 28, Figure 7 F-ums kelletii Forbes, Free. Zool. Soc. London, Ft. 18, p. 274, pi. 9, fig. 10, 1850. Siphonalia kellettii Forbes, Lischke, Japanische Meeres-Conchylien, p. 38, pi. 3, figs. 3, 4, 1869; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 663, 1864; Tryon, Man. Conch., Ser. 1, Vol. 3, p. 134, pi. 54, fig. 352, 1881; Dall, Trans. Wagner Inst. Sci., Vol. 3, pt. 1, p. 122, 1890; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 229, pi. 4, fig. 5, 1903. Siphonalia kelletii Forbes, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 264, 1888. Fiisiis Toperi DaU, Nautilus, Vol. 12, p. 4, 1898, type of new section Roperia, 1898. Fiisus (Roperia) roperi DaU, Proc. U. S. Nat. Mus., Vol. 24, pi. 34, fig. 3, 1902, in part. Roperia roperi Dall, of authors. Siphonalia kelletti Forbes, English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914. Kelletia kellettii Forbes, DaU, Bull. 112, U. S. Nat. Mus., p. 89, 1921; E. K. Jordan, BuU. So. Calif. Acad. Sci., Vol. 23, p. 149, October, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 182, 1927. Fminus (Roperia) roperi Dall, BuU. 112, U. S. Nat. Mus., p. 88, 1921, in part; Oldroyd, 1927, in part, see Tntonalia poulsoni. Type specimen: In the British Museum. Type locality: California; Recent. Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 643 Pliocene: Lower Pliocene of Elsmere Canyon and east of Fernando Pass (S. D. S. N. H. localities 203, 216, H. R. G., collector); lower Fernando of Elsmere and Holser canyons (English); middle Pico near Pico Canyon and near Holser Canyon, Los Angeles County (S. D. S. N. H. localities 217a, 228, and 230, H. R. G., collector). Pleistocene: Lower Quaternary of Magdalena Bay, Lower California, Mexico (Jordan); Pleistocene of Pacific Beach, San Diego, California (Arnold, 1903); upper San Pedro series of San Pedro, Los Cerritos (i. e., Signal Hill), and Crawfish George's, Los Angeles County (Arnold). Recent: Santa Barbara, California, south to San Quintin Bay, Lower California, Mexico; also Japan (Dall, 1921). This well-known species has a higher spire and longer anterior canal than K. diego- ensis (Dall) and the nodes are less elongate axially. The spiral sculpture appears to be less sharp. On all the specimens we have seen the upper margins of the whorls encroach considerably on the previous whorls, a character which is somewhat less pronounced on K. diegoensis. Kelletia keUetii ranges from the lower PUocene to the Recent in California but appears to have migrated southward during the cold uppermost Pliocene and lower Pleistocene times. "Fusus" roperi Dall appears to be the young. Kelletia (Kelletia) diegoensis (Dall) Chrysodomus diegoensis Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 298, 1874. "Shell Large, sohd, fusiform; apparently, when fresh, of a brownish yellow color; sculpture consisting of regular, even, rounded, spiral ridges, slightly larger toward the anterior end of the last whorl, with from two to four sharp grooves intercalated between each two of the primary ridges, forming fine and small secondary threads of spiral sculpture. On the posterior whorls these are crossed by slightly oblique waves or plications, evanescent toward the sutures and strongest on the apical whorls. On the last whorl and a half these are absent. The posterior fourth of the whorls shghtly impressed and the sutures appressed. Whorls eight and a half, periphery rounded. Canal short, recurved, siphonal fasciole short and strong. Outer lip slightly thickened behind the edge, inner lip covered with an even callus. Columella smooth, slightly arched; throat with internal sharp threads, as in C. dirus, ending some distance behind the edge of the outer Up. "Length, 4.0 inches; width, 1.75 inches. Length of aperture, 1.8 inches. Deflection, 42°. "The upper whorls of this shell bear a shght resemblance to Siphonalia kellettii; though the transverse waves are very different from the knobs of that species. There appears to be no special reason for referring the present form to Siphonalia, while it presents so great a resemblance to many Chi-ysodomi. "Habitat, with other Tertiary fossils, in a sand-bed cut through by a well-shaft, at San Diego, CaUfoniia, at a depth below the surface of about one hundred and fifty feet." (Dall.) Type specimen: Formerly in the museum of the California Academy of Sciences, probably destroyed in the San Francisco earthquake of 1906. Pliocene: At the type locality, San Diego well, middle Pliocene. There seems to be a group of Pliocene forms that differ somewhat from the living keUetii. They have stronger spiral sculpture, and their nodes are more elongate axially, tending to become obsolete on the body whorl. As these forms are known only by rare or poorly preserved specimens, it is difficult to determine whether they are all varieties of keUetii or of one or more extinct Pliocene species. K. diegoensis is now known only from the original description quoted in full above. K. gilberti is known from two fairly good specimens described by Moody and from others identified by Waterfall. A', kettle- manensis is known from numerous, but so far as the writers know, all poorly preserved specimens. It is likely that these Pliocene forms, insofar as they are distinct from kel- letii, will fall into the synonymy of diegoensis; but until material can be found in the San Diego formation for comparison, the writers have preferred to list them separately. 644 San Diego Society of Natural History [ Memoirs K. gilberti appears to have less elongate nodes than diegoensis, more like those of kelletii; but it has a shorter anterior canal than kelletii. The specimens of kelletii from the lower Pliocene of Elsmere Canyon sometimes have nearly obsolete nodes on the body whorl. K. kettlemanensis appears to have a lower spire, with a larger apical angle, and seems a little more likely to be distinct. All of these forms have primary, secondary, and tertiary spiral sculpture, which is practically a family character; their nodes run about nine to a whorl; and their rather thick shells have lirations on the insides of the outer lips. They are about twice as large as the forms of the Searlesia group. Kelletia (Kelletia) gilberti (Moody) Siphonalia gilberti Moody, Univ. Calif. Piibl. Geol., Vol. 10, p. 51, pi. 1, figs. 5, 5a, 1916. Cantharus gilberti Moody, Waterfall, Univ. Calif. Publ. Geol, Vol. 18, pp. 78, 82, 89, 1929. Type specimen: In the collection at the University of California, No. 11,077. Type locality: Fourth and Broadway, Los Angeles, lower part of the upper Pliocene. Pliocene: At the type locality; also "lower" Pico near Ventura, middle Pliocene (Waterfall). Kelletia (Kelletia) kettlemanensis (Arnold) Thais kettlemanensis Arnold, U. S. Geol. Surv., Bull. 396, pp. 27, 69, pi. 15, fig. 4, pi. 21, fig.s. 1, la, Jan. 15, 1910; Bull, 398, pi. 37, fig. 4, pi. 43, figs. 1, la (same figure.s), 1910; Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 213, 221, 1917. Type specimen: In the U. S. National Museum, No. 165,585. Type locality: U. S. G. S. locality 4680, base of the Etchegoin formation, lower middle Pliocene, of the Kettleman Hills district, middle Cahfornia. Pliocene: At the type locality; common in the Jacalitos formation (Arnold) ; common in the Chione elsmerensis and Turritella nova zones, Coalinga district; also lower Sargent (Nomland). For a discussion of this form and the preceding see K. diegoensis. Kelletia (? Kelletia) posoensis (Anderson and Martin) Siphonalia posoensis Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 79, pi. 4, fig. 2, 1914. Type specimen: At the California Academy of Sciences, No. 174. Type locality: In the bed of a small creek near the center of Sec. 34, T. 28 S, R. 15 E, San Luis Obispo County. Miocene: At the type locality, probably middle Miocene. This is a peculiar, elongate species. Subgenus SEARLESIA Harmer, 1914 Searlesia F. W. Harmer, Mon. Palaeo. Soc, Vol. 67, Plio. Moll. Gt. Brit., Vol. 1, p. 135, pi. 13, fig. 1, 1914; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 215, 1918. Type (by original designation), Trophon costifer S. V. Wood, figured by Harmer, op. cit., pi. 13, fig. 1; Pliocene of England; Recent, North Atlantic. "Shell solid, fusiform; apex blunt but not bulbous; ornamented by spiral lines or ribs and by strong longitudinal costae; canal usually short, open, straight or bending slightly to the left." (S. V. Wood.) Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 645 Dall has amplified this description by adding details observed on Kelletia (Searlesia) dira (Reeve) . K. dira is a typical Searlesia very closely related to the British type species. Ball's description follows: "Nucleus (of S. dirus) smooth, of two laxly coiled smooth whorls changing abriijitly into the adult sculpture of few strong axial ribs crossed by numerous spiral threads. The shell-structure subtranslucent, dark colored; the shell short-fusiform, periostracum inconspicuous; aperture shorter than the sjjire, the outer lip thickened and internally lirate; the body callous, with a narrow chink between the reflected enamel and the strong siphonal fasciole; canal short, open, slightly recurved. Radular formula l/2: 1/3: 1/2, the medium rachidian cusp longer than the others." Kelletia (Searlesia) dira (Reeve) Plate 28, Figure 6 Buccinum diru7n Reeve, Conch. Icon., Vol. 3, Buccinum, pi. 12, fig. 92, Dec, 1846. Fusvs incis-us Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 141, 1849; U. S. Exploring Exped., Vol. 12, p. 232, 1852, Atlas Mollusca, pi. 16, figs. 283, 283o, 1856; Harmer, Mon. Pal»o. Soc, Vol. 67, Plio. Moll. Gt. Brit., Vol. 1, p. 138, 1914. Eulhria dira Reeve, Tryon, Man. Conch., Ser. 1, Vol. 3, p. 151, pi. 72, figs. 232, 233, 1881. Chrysodomus dirus meridiei Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 52, pi. 1, figs. 9a, 96, 1916. Searlesia dira Reeve, Dall, U. S. Nat. Mus., Bull. 112, p. 98, pi. 8, fig. 1, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 237, 1927. Shell of moderate size, heavy, stoutly sub-fusiform ; whorls ventricose ; spiral sculpture of rather uniform spiral cords and occasional intercalated threads; axial sculpture of broad axial undulations becoming obsolete on the body whorl; aperture ovate, outer lip simple, with lirations within ; anterior canal short, slightly reflexed; mner lip slightly concave, with a thin callus wash; siphonal fasciole variable m strength, often with an umbilical chink between it and the lower extension of the inner lip. Length, 41 mm.; maximum width, 19 mm. Pliocene: "Fernando" at Fourth and Broadway, Los Angeles (Moody). Pleistocene: Santa Barbara (Dall, 1921). Recent: Chirikoff Island, Alaska, to Monterey, California. This is a rather common species on the rocky coasts of California at least as far south as Monterey. A large series of these shells at Stanford University shows variation in height of spire, shape of aperture, length and amount of twist of the anterior canal, and thickness of the outer lip. Specimens occasionally attain a length of over 50 mm. "Fusus incisus" Gould, as figured in the Exploring Expedition Atlas, was applied to a peculiar specimen of dira with axial undulations on the body whorl. Some large specimens in the collection at Stanford University have these rib-like irregularities on the ultimate whorl, but they are abnormal. The variety meridiei Moody, based upon a single specimen, is too close to living variants to warrant a separate name. "Chryso- domus" portolaensis (Arnold) is very closely related and similar in appearances. "Chryso- domus" sitkensis (Middendorff) is probably a synonym. K. dira (Reeve) is closely related to K. costifera (S. V. Wood),' the type of the genus, which occurs in the Red Crag of Eng- land. The typical form of the English species has stronger axial ribs, and these ribs are also present on the body whorl ; but some of the variants are much like California speci- mens of K. dira. Kelletia (Searlesia) dira (Reeve) variety portolaensis (Arnold) Fusns (Buccinofusus) portolaensis Arnold, Proc U. S. Nat. Mus., Vol. 34, p. 385, pi. 37, fig. 8, Aug. 8, 1908. ' Chrysodomus portolnnisis Arnold, U. S. Geol. Surv., Bull. 396, p. 158, pi. 27, fig. 9, January 15, 1910; Arnold and Ander- son, Bull. 398, pi. 49, fig. 9, 1910. Type specimen: In the U. S. National Museum, No. 165,473. ' Trophon costi/erum S. V. Wood, Mon. Palseo. Soc, Vol. 1, Crag. Moll,, Pt. 1, p. 48, pi. 6, fig. 9, 1848. 646 San Diego Society of Natural History [ Memoirs Type locality: White Creek, 19 miles northwest of Coalinga, Fresno County ; Etchegoin Phocene. Pliocene: At the type locality; on Sausal Creek, one-half mile southwest of Portola, Santa Cruz Quadrangle (Arnold, 1908); several localities in eastern Monterey County and western Fresno County. This variety is so close to the typical form that the distinctions may be found to lack significance. It appears to have a longer anterior canal and the spiral cords may be slightly heavier. It is possible that the variety meridiei is a synonym of portolaensis rather than of the typical form. Kelletia branneri (Clark and Arnold) ^ is closely related to K. dira and is very similar to variety portolaensis (Arnold). K. dalli (Clark),- of the San Lorenzo Oligocene, is another closely related form. Genus CANTHARUS Bolten, 1798 Cantharus Bolten, Mus. Boltenianum, p. 132, 1798; Meek, Kept. U. S. Geol. Surv. Territories, Vol. 9, p. 377, 1876; Cossmann, Ann. Soc. Roy. Malac. Belg., Vol. 24 (Ser. 4, Vol. 4), p. 137, 1889; Iredale, Proc. Malac. Soo. Lon- don, Vol. 10, p. 221, 1912; Suter, Man. New Zealand Moll., p. 393, 1913; not Ca7Marus Cuvier, 1829, Pisces; not Canlharis LinnEeus, 1758, Insecta. "Rapana 0" Schumacher, Ess. Nouv. Syst. Hab. Vers Test., p. 214, 1817. Pollia Gray in Sowerby, Gen. Rec. Foss Shells, Vol. 2, footnote in text to pis. 256, 257, 1834; Gray, Zool. Beechey's Voy., p. Ill, 1839, type, by monotypy, Triton undosus Lamarck; Iredale, Proc. Malac. Soc. London, Vol. 10, p. 221, 1912 (in discussion of Quoyula). Trilonidea Swainson, Treat. Malac, p. 302, 1840; Gray, Proc. Zool. Soc. London, Pt. 15, p. 133, 1847, type Buccinum undosum Linnaeus; Iredale, Proc. Malac. Soc. London, Vol. 10, p. 221, 1912. Solenosteira Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 122, 1890, type Pyrula anomala Reeve. T^jpe (by subsequent designation, Suter, 1913), Cantharus glohularis Bolten = Buccinum tranqueharicum Gmelin; Indian Ocean, Recent; figured by Reeve, Conch. Icon., Vol. 3, Buccinum, sp. 17, pi. 3, Dec, 1846. Shell of moderate size, heavy, bucciniform but with anterior portion longer; aperture and spire of about equal length; sculpture consistmg of spiral riblets and axial undulations; uuier side of outer lip -with crenulations ; columella nearly smooth or with a few small ridges. ^'Rapana fi" of Schumacher was exemplified by only one species, " Rapana flavescens," which is a new name for the "Nassa undosa tranqueharica" of Chemnitz (Conch. Cab., Vol. 4, p. 35, pi. 123, figs. 1146, 1147, 1780), now more properly called Cantharus tran- quebaricus (Gmelin), the type of Cantharus Bolten. The "Rapana a. of Schumacher had for sole example "Rapana foliacea," which is the Rapana bezoar Linnaeus, 1767, and is therefore very different from Schumacher's p division. Pollia Sowerby is synonymous, as is also Tritonidea Swainson. Solenosteira Dall has a longer aperture and canal but is very close in other respects to the typical form. Siphonalia A. Adams,' typified by S. cassidariceformis (Reeve), is similar in form but can be distinguished by its thin shell and lack of conspicuous epidermis. Siphonalia is a warm-water Oriental genus, which is well represented in the earlier Tertiary of Cali- fornia, along with several other Asiatic groups. Pisania Bivona is based on M. pusio Linnseus, which is an elongate species, with a smooth surface.* Cantharus probably began in the Eocene and is well represented in the present tropical seas. ■ Univ. Calif. Publ. Geol., Vol. 14, p. 159, pi. 30, figs. 3a-b, 1923. '- Univ. Calif. Publ. Geol., Vol. 11, p. 175, pi. 20, figs. 5, 9, 15, 191S. > Annals and Mag. Nat. Hist., Ser. 3, Vol. 11. p. 202, 1863; Cossmann, Ann. Soc. Roy. Malac. Belgique, Vol. 24, (Ser. 4, Vol. 4), p. 149, 1889; "type: S. cassidarixforviis (Reeve)." I Pisania Bivona, Effem. Scien. Lett. Sicilia, Vol. 2, p. 8, pi. 2, figs. 6a-d. 1832; Herrmannsen, Indieis Gen. Malac, Vol. 2, pp. 273, 274, Dec. 7, 1847; Bucquoy. Dautzenberg. and Dollfus, Moll. Mar. Roussillon, Vol. 1, p. 25, 1882; Cossmann, .\nn. Soc. Roy. Malac. Belg.. Vol. 24. p. 139, 1889. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 647 Cantharus fortis (Carpenter) Plate 28, Figure 2 Pisania fortis Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 17, p. 277, 1866; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 260, ISSS; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 227, 1903; McLaughlin and Waring, BuD. 69, Calif. State Mining Bureau, Map Folio, pi. 1, fig. 48, 1914. Canlharis fortis Carpenter, Carson, Bull. So. Calif. Acad. Sci., Vol. 24, pt. 2, p. 33, August 17, 1925; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, pp. 78, 79, 89, pi. 5, figs. 5, 6, 1929. Shell with strong, rounded spiral ribs and smaller interribs, also prominent axial ribs which are crossed by the spiral sculpture mthout interruption or modification; body whorl slightly shouldered, the axial ribs obsolete on the lower portion. Type locality: Santa Barbara; Pleistocene. Pleistocene: Santa Barbara (Carpenter; Cooper); Pacific Beach, San Diego County; upper San Pedro series of San Pedro and Deadman Island, rare (Arnold, 1903). This species is very similar to the living Cantharus insignis (Reeve) and is unques- tionably closely related. Cantharus fortis (Carpenter) variety angulatus (Arnold) Pisania fortis Cpr. var. angulata Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 536, pi. 50, figs. 6, 7, 1907; Eldridge and .\rnold, U. S. Geol. Surv., Bull. 309, pi. 40, figs. 6, 7, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914; Nomland, Vol. 10, p. 221, 1917. Solenosteira angelensis Carson, BuU. So. Calif. Acad. Sci., Vol. 24, pt. 2, p. 32, pi. 1, figs. 3, 5, August 17, 1925. Cantharus angulatus Arnold, Carson, op. cii., p. 33, 1925. Broader than typical Cantharus fortis and with an angulated shoulder on the whorls. Length, 80 to 100 mm., -svidth, 40 mm. Type specimen: In the U. S. National Museum, No. 164,975. Type locality: Third Street tunnel, city of Los Angeles; PUocene. Pliocene: Lower Pliocene of Elsmere Canyon, two and a half miles southeast of Newhall (Arnold); lower Fernando of Holser Canyon, Los Angeles County (English); Third Street tunnel in Los Angeles (Arnold); lower Purisima of middle California (English); lower Merced and Etchegoin formations of middle California (Nomland) ; mouth of Brea Canyon, Puente Hills, Los Angeles County (Car- son, as Solenosteira angelensis); "lower Pico," middle Pliocene, near Ventura (Waterfall). The spiral ribs on this variety do not seem to be so prominently elevated as on most of the specimens of the Pleistocene typical variety. The axial ribs are likewise nearly or entirely wanting. This form seems to grade into humerosus in the lower Phocene of Elsmere Canyon. Cantharus humerosus (Gabb) Plate 28, Figure 3 Neptunea humerosa Gabb, Geol. Surv. Calif., Palseo., Vol. 2, pp. 45, 71, pi. 14, fig. 3, 1868-9; Cooper, Calif. State Min- ing Bureau, Bull. 11, p. 80, 1896; Arnold, U. S. Geol. Surv., Prof. Paper 47, p. 27, 1906; Eldridge and Arnold, U. S. Geol. Surv., Bull. 309, p. 25, 1907; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 212, 1914; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 395, pi. 32, figs. 2, 3, 1927. Chrysodomus arnoldi Rivers, BuU. So. Calif. Acad. Sci., Vol. 3, no. 5, p. 70, May, 1904; .Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 526, pi. 50, fig. 10, 1907 Qisted questionably); English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914 (not positively identified). Chrysodomus cf. arnoldi Rivers, .Arnold, U. S. Geol. Surv., Bull. 309, p. 252, pi. 40, fig. 10, 1907. Cantharus breaensis Carson, Bull. So. Calif. Acad. Sci., Vol. 24, pt. 2, p. 31, pi. 1, fig. 2, Aug. 17, 1925. Cantharus ashleyi Carson, op. cit., p. 31, pi. 1, figs. 6, 7, 1925. Cantharus elsmerensis Carson, op. cit., p. 32, pi. 1, fig. 4, 1925. Cantharus arnoldi Rivers, Carson, op. cit., p. 34, pi. 1, fig. 1, 1925. 048 San Diego Society of Natural History [ Memoirs Shell of medium size, whorls ventricose, with a shoulder of variable strength at the upper third, suture emphasized by a collar ; aperture ovate, anterior canal twisted, coliunella incrusted, siphonal fascicle prominent ; sculpture of fine spiral cords or threads. Type specimens: Lectotype of humerosus, in the Academy of Natural Sciences of Philadelphia (fide Stewart) ; of arnoldi, unknown to the authors; of breaensis, ashleyi, and elsmerensis, at Stanford University. Type locality: Pliocene of San Fernando Pass, Los Angeles County. Pliocene: Near Wiley's on the San Fernando Pass, Los Angeles County (Gabb); lower Fernando of Elsmere Canyon (Eldridge and Arnold; English); lower Pliocene of Elsmere Canyon, and middle Pliocene of San Fernando Pass and thence occurring all along the outcrop to Pico Canyon and to Holser Canyon, various S. D. S. N. H. localities (coll. by H. R. G.); Gavin Canyon, west of San Fernando Pass and from near San Fernando Tunnel (as Cantharus ashleyi, Carson); Brea Canyon, Puente Hills (as Cantharus breaensis, Carson), all Los Angeles County. ? Pleistocene: "Pliocene," one specimen from Cra'n'fish George's near San Pedro, Los Angeles County (Rivers). Cantharus humerosus (Gabb) is common in the Pico formation of the eastern portion of the Santa Clara Valley and around San Fernando Pass. The one Pleistocene record might have been occasioned by some error in labeling, and in any case is probably an error. "Chrysodomus" kernensis Anderson and Martin,' from the lower Miocene of Kern River, Kern County, appears to belong to this group. It has a very small siphonal fasciole and intercalary spirals. It is of the general shape of Neptunea antiqua and shows how difficult it is to separate Cantharus from Neptujiea. C. humerosus is about midway between the type of Neptunea and the type of Cantharus, but it is here placed with the latter because of its relation to fortis, its thick shell for a rather small size, and the lirations on the interior of the outer lip, mentioned by Gabb. Cantharus anomalus (Reeve) Pyrula anomala Reeve, Conch. Icon., Vol. 4, Pyrula, species 9, pi. 3, figs. 9, 12 (tj-pical), June, 1847. Pxjrula pallida Broderip, in Sowerby, Thes. Conch., Vol. 4, Pyrtda. p. 100, sp. 3, pi. 5, figs. 37, 38, 1880. Solenosteira (Pyrula) anomala Reeve, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 122, 1890. Solenosteira anomala Reeve, Dall, Nautilus, Vol. 32, p. 23, 1918; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 453, 1926. Solenosteira pallida Broderip and Sowerby, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Pliocene: Imperial formation. Coyote Mountain, Imperial County, California (Hanna). Pleistocene: Lower Quaternary of Magdalena Bay, Lower California, Mexico (Dall, 1918, as S. anomala R«eve; Jordan, as 5. pallida B. and S.). Recent: San Ignacio, west coast of Lower California, to Panama. There is little doubt that the Pyrula anomala Reeve, and the P. pallida Broderip (MS. ?) in Sowerb}-, are the same species. Sowerby's figures seeem to be somewhat in- termediate between Reeve's two extremes. C. anomalus is the type of Solenosteira. Cantharus elegans (Gray) Triton (P-usio) elegans Gray, in Griffith's Cuvier, Anim. Ivingd. Moll., p. 600, pi. 25, fig. 2, 1834. Canihants elegans Gray, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 213, 1909; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Pleistocene: Lower Quaternary of Magdalena Bay, Lower California, Mexico (Jordan) ; upper Pleistocene of the coast of Oaxaca, Mexico (coll. by R. H. Palmer, specimens in the collection at Stanford Uni- versity). Recent: Point Abreojos, Lower California, Mexico, to Peru (Jordan). • Frank M. Anderson and Bruce Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 78, pi. 4, figs. 6a, 6b, December 30, 1914. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 649 Cantharus sanguinolentus (Duclos) Purpura sanguinolenta Duclos, Guerin, Mag. de Zool., Vol. 5, p. 22, fig. 1, 1S33. Cantharus sanguinolentus Duclos, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 214, 1909. Pleistocene: Upper Pleistocene, coast of Oaxaca, Mexico (collected by R. H. Palmer). Recent: Mazatlan and south to Guayaquil (Dall, 1909). "Miirex" vihex Broderip^ of the Panama and the we.st Mexican regions may be a Cantharus. It is certainly not a Murex. Genus MACRON H. and A. Adams, 1853 Macron H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 132, 1853, list includes astkiops Reeve, and kellettii A. Adams; Melvill, Journ. Conchology, Vol. 10, p. 326, 1903; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 141, 1901. Type (by subsequent designation, Cossmann 1901), Macron kellettii (A. Adams). Shell ovate, heavy; strongly spirally sculptured or smooth; whorls moderately ventricose, body whorl much larger than penultimate whorl; aperture ovate, outer lip with a tooth-like projection anteriorly, iimer lip gently concave; anterior canal short, notched; epidermis strong, brownish or chestnut; operculum homy, with apical nucleus. Length, 10 to 100 mm. Geologic range: Miocene to Recent. The type of this genus is a variety of M. cethiops (Reeve). Pseudoliva Swainson- seems to be related to Macron. The type of Pseudoliva has a very short, sharp spire. It is figured by Chemnitz, Swainson, the Adams brothers and others. The operculum as figured by H. and A. Adams (and reproduced by Fischer, 1884) has a medio-lateral nucleus, but a specimen of plumbea in the Oldroyd Collection at Stanford University has an apical nucleus like that of the Macron operculum. Macron aethiops (Reeve) Buccinum xthiops Reeve, Conch. Icon., Vol. 3, pi. 13, fig. 108, 1847. Macron xthiops Reeve, Melvill, Journ. Conch., Vol. 10, no. 11, p. 327, 1903; Dall, Nautilus, Vol. 32, p. 23, 1918; E. K. Jordan, BuU. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Shell large, with strong, rather flat, spiral cords separated by wide interspaces, and a prominent, subsutural, chamieled tabulation; siphonal fascicle prominent. Large specunens measure 95 mm. in length and 55 mm. in width. Pleistocene: Magdalena B.ay, Lower California, Mexico (Dall; Jordan, 1924, as "lower Quaternary"); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: San Quintin Bay to Gulf of California, Mexico (Jordan, 1924). The typical cethiops differs from the variety kellettii in the prominence of the spiral sculpture and subsutural tabulation. M. hartmanni Hertlein and Jordan, a strongly tabulated variety, has less heavy spiral sculpture and, so far as known, does not attain the size of M. cethiops. 1 Proo. Zool. Soo. London for 1832, p. 175; Reeve, Conch. Icon., Vol. 3, Marex, pi. 34, fig. 175, 1845. 2 Treat. Malac, pp. 82, 306, text fig. 3a, 1840, type designation (p. 82) "Buccinum plumbeum of Linnaean authors"; (p. 306) monotype P. vlumbea Chemnitz (Neues Systematisches Conchylien Cabinet, Vol. 11, p. 86, pi. 188, figs. 1806-7, dated 1795). 650 San Diego Society of Natural History [Memoirs Macron aethiops (Reeve) variety kellettii (A. Adams) Plate 28, Figure 8 Pseudoliva kelleltii A. Adams, Proc. Zool. Soc. London for 1853, p. 185. Macron kelletlii A. Adams, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 664, 1864; Tryon, Man. Conch., Ser. 1, Vol. 3, p. 214, pi. 82, fig. 477, 1881; Cooper, Calif. State Mining Bureau, Bull. 4, Pt. 3, p. 27, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 230, 1903; MelviO, Journ. Conch., Vol. 10, p. 326, 1903. Macron xthiops Mletlii A. Adams, Dall, U. S. Nat. Mus., Bull. 112, p. 89, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 183, 1927. Shell like that of M. cethiops, but with very famt or obsolete spiral sculpture on the upper part of the body whorl and the spire. Pliocene: Ventura County (Cooper), may be Pleistocene. Pleistocene: One specimen in upper San Pedro series at San Pedro (Arnold); upper Pleistocene at Signal Hill (specimen in Oldroyd Collection at Stanford University) ; Pleistocene of San Joaquin Bay, Orange County (Cooper). Recent: Catalina Island 7 (Cooper); Lower California and the Gulf of California (Pall, 1921). The strong spiral sculpture of the typical cethiops is only present on the lower part of the body whorl of yariety kellettii. Macron orcwiii Dall/ of the Recent fauna of Mag- dalena Bay, has fine, close spiral striations and no channel at the suture. Macron vter- riami Arnold- from the lower Miocene at the head of Topanga Canyon, three miles south of Calabasas, Los Angeles County, is much like variety kellettii, but is a more slender shell with a narrower tabulation below the suture. Arnold suggests that it may be the precursor of kellettii, though it would seem that M. hartmanni Hertlein and Jordan is more apt to be a direct ancestor. Macron lividus (A. Adams) Pseudoliva livida A. Adams, Proc. Zool. Soc. London, Pt. 22, p. 136, 1854. Macron lividus A. Adams, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 664, 1864; Keep, West Coast Shells, p. 20, fig. 2, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 230, 1903; DaU, U. S. Nat. Mus., Bull. 112, p. 89, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 183, 1927. Macron livida A. Adams, Melvill, Journ. Conch., Vol. 10, p. 329, 1903. Shell small, elongate ; whorls moderately ventricose ; sculpture consisting of faint spiral threads on the basal portion of the body whorl. Large specimens measure 23 mm. in length and 13 mm. in width. Pleistocene: One specimen from the upper San Pedro Pleistocene at the "hunber yard," San Pedro (Arnold). Recent: Farallone Islands, California, to San Bartolome Bay, Lower California, Mexico (Dall, 1921). From the Miocene of Lower California, southwest of San Ignacio, Hertlein and Jor- dan^ described Macron hartmanni. It appears to be related to Macron cethiops variety kellettii, but the spiral sculpture on the lower part of the body whorl is finer and the posterior canal is a little more distant from the body whorl. It was collected from the Isidro formation, associated with TurriteUa ocoyana Conrad. Genus VOLUTOPSroS Morch, 1857 Siromlella Gray, Guide MoU. Brit. Mus., p. 13, Jan., 1857, not Stroinbella Schliiter, Syst. Conch. Samml., p. 22, 1838. Volvtopsivs Morch, Fort. ov. Gronl. Bloddyr., p. 13, April, 1857; DaU, Proc. U. S. Nat. Mus., Vol. 54, p. 221, 1918. Volutopsis Morch, Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 57, 1873; G. O. Sars, Moll. Reg. Arct. Norv., p. 268, 1878. Type (fide Dall, 1918), Volutopsius largillierti (Petit de la Saussaye), described as Fusus in the Journ. de Conchyl., Vol. 2, p. 254, pi. 7, fig. 6, 1851; also figured by Tryon >Proc. Biol. Soo. Washington, Vol. 31, p. 5, 1918. 2 Proc. U. S. Nat. Mus., Vol. 32, p. 529, pi. 41, figs. 4, 4o, June 15, 1907; also figured in U. S. Geol. Surv., Bull. 309. pi. 28, figs. 4, 4a, 1907. « Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 629, pi. 21, fig. 5, 1927. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 651 as Neptunea (Volutopsius) norvegica Chemnitz, Man. Conch., Vol. .3, p. 119, pi. 48, figs. 276, 277, pi. 49, figs. 278, 279, pi. 50, fig. 288, 1881, the figure 278 being a reproduction of Petit's; see also Harmer, Mon. Pateo. Soc, Vol. 67, PUo. Moll. Gt. Brit., Vol. 1, p. 152, pi. 15, fig. 2, 1914. Shell resembUiig that of Neptunea, but with a large body whorl, a more ample aperture, a short, hardly differentiated anterior canal, and a short, blunt, few-whorled spire. Volutopsius eurekaensis Martin Volutopsius eurekaensis Martin, Univ. Calif. Publ. Geo!., Vol. 8, p. 190, pi. 19, fig. 3, 1914. Type specimen: In the collection at the University of California. Type locality: Near the mouth of Bear River, Humboldt County, California; upper Miocene (Martin), possibly lower Pliocene. Miocene or Pliocene: At the type locality (Martin). Volutopsius mesleri (Dall) Chrysodomus mesleri DaU, U. S. Geol. Surv., Prof. Paper 125-C, p. 28, pi. 5, figs. 2, 3, 1920. Type specimen: In the U. S. National Museum. Type locality: Center Creek mines, two miles north of Nome, Alaska; Pliocene. Pliocene: At the type locality and questionably from Center Creek, one and a half miles north of Nome, Alaska (Dall). This species is based upon two badly worn fragments. It has strong, rounded nodes and was said by Dall to be nearest allied to N. satura (Martyn). However, it seems more probable that Dall's fragments are from an immature individual of Volutopsius kennicotti (Dall).^ Volutopsius seems to be very closely related to typical Neptunea, being distinguished typically by its relatively enlarged body whorl and weak sculpture. The species kennicotti (species, or variety of behringii) appears to be intermediate between Neptunea satura and Volutopsius. Its strong, curved, pinched, axial waves may represent an accentuation of axial irregularities such as are sometimes found on antiqua, the curving of the waves being, perhaps, a more unusual feature than their elevation. The form kennicotti has traditionally been assigned to Beringius, a name that Dall was afraid would fall as a synonym of Jumala. - However, the type of Beringius is Neptunea {Beringius) crebricostata (Dall),^ which has a shell with coarse spiral ridges like those of Neptunea decemcostata. It can be distinguished from Neptunea only by its short anterior canal and is more likely to conflict with Ancistrolepis than with Jumala. It is no more like Jumala than it is like kennicotti. Jumala^ may be useful as a section 1 Buccinum kennicotti Dall, Amer. Journ. Conch., Vol. 7, p. 108. pi. 15, fig. 1 (espl. of plate on p. 160), Nov. 2, 1871; figure reproduced by Tryon, Man. Conch., Vol. 3, p. 294 (expl. plate), pi. 50, fig. 290, 1881, who considers it conspecific with Trilonium behringii Middendorff, which he describes and figures, op. cit., p. 121, pi. 49, fig. 280, pi. 50, fig. 289, as Neptunea behringii, assigning Dall's kennicotti to the variety caslanea Morch. 2 Proc. Calif. Acad. Sci., Vol. 7, p. 6. 1877; Sci. Res. Expl. Alaska, pi. 2, figs, la-c, proofs sent to friends in 1879 but not really published until later; Proc. U. S. Nat. Mus., Vol. 24, pi. 35, fig. 1, 1902; also figured by Tryon, Man. Conch., Vol. 3, p. 118, pi. 48, fig. 274, 1881, and by Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 193, pi. 23, fig. 1, 1927. * Jumaia Friele, Norwegian North Atlantic Expedition, I, p. 6, 1882; Dautzenberg and Fischer, "Moll. Prov. Camp, de rHirondelle et de la Princess-Alice," R68. Camp. Sci. Albert 1, Prince de Monaco, Vol. 37, p. 64. 1912; "H Ukko, Friele in Norman, Ann. and Mag. Nat. Hist., Ser. 6, Vol. 12, p. 352, Nov., 1S93, new name for Jumala proposed because it was discovered that Jumala is the term used by the Christian Lapps for God. The type is Fusu^ iurtoni Bean, Loudon's Mag. Nat. Hist., Vol. 7, p. 493, 1834; Howse, Ann. and Mag. Nat. Hist., Ser. 1, Vol. 19, p. 160, pi. 10, figs. 6-10, 1847; Reeve, Conch. Icon., Vol. 4, Fusua. pi. 20, species 83, 1848; Neptunea (.Volutopsius) tuTtoni Bean, Tryon, Man. Conch., Vol. 3, p. 119, pi. 48, fig. 275, pi. 49, figs. 281, 282, 283, 1881; coasts of Britain. 662 San Diego Society of Natural History [ Memoirs of Volutopsius with a high spire. It has very weak sculpture, with a short anterior canal. Dall reported two forms^ of Volutopsius from the fossil beds at St. George Island (Pribilof Islands) which he believed to be related to V. malleatus^ and V. regularise Dall. The age of the deposit was believed to be late Pliocene. Subgenus PYRULOFUSUS Beck in Morch, 1869 Pyrulofusus (Beck MS.) Morch, Mem. Soc. Malac. Bclgique, Vol. 4, p. 20, 1869, sole example, Fusus deformis Reeve; Friele, Jahrb. Mai. Ges., Vol. 6, p. 280, 1879; N. Atl. Exp., Vol. 1, p. 8, pi. 1, fig. 8, pi. 4, figs. 11-13, 1882; Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 523, 1902; Dautzenberg and Fischer, Res. Camp. Sci., .-Ubert I, Prince de Monaco, Pt. 37, p. 67, pi. 1, figs. 6, 7, 1912; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 223, 1918. Hdiolropis Dall, Proc. Calif Acad. Sci., Vol. 5, p. 61, April, 1873. Pyrolofusus Morch, Krause, Arch. f. Naturg., Vol. 51, p. 282, 1885. Pyrolofusus (Beck) Morch, Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 523, 1902. Type (by monotypy, ^de Dall, 1918), Fusus deformis Reeve, Conch. Icon., Vol. 4, Fusus, pi. 12, figs. 45a-6, Dec, 1847, "Hab. Spitzbergen." Shell large, usually sinistral; spire low, of few whorls, with a large nucleus; sculpture of spiral striations or threads and a few rude axial waves; aperture ample, with a very short or indefinite anterior canal, tapering columella, and no siphonal fasciole; operculum horny, small, with apical nucleus. This subgenus is essentially a sinistral Volutopsius with stronger axial sculpture. Volutopsius (Pyrulofusus) schraderi (Dall) Pyrulofusus schraden DaU, U. S. Geol. Surv., Prof. Paper 125-C, p. 29, pi. 5, figs. 10, 13, 1920. Type specimen: In the U. S. National Museum. Type locality: Forty miles up Colville River from its mouth at the Arctic coast, in silt beds, 80 feet above the river, five to fifteen feet below the base of loess, twenty feet below the surface of the soil; supposedly Pliocene. Pliocene: At the tjrpe locality (Dall). Dall reported^ two fossil forms of Pyrulofusus from the "late Pliocene" of St. George Island (Pribilof Islands), which he suggested were related to P. deformis "Gray" (?) and P. harpa Morch. Genus NEPTUNEA Bolten, 1798 Tritonium Miiller, Zool. Danicse Prodr., p. 243, 1776, list includes T. undalum, T. antiquum, T. despecium, and others, in part only, not the type, Buccinum undalum- Linnaeus, cited by Schumarher, Ess. Nouv. Syst. Habit. Vers Test., p. 209, 1817, fide Stewart, Special Publ. No. 3, Acad. Nat. Sci. Phila., p. 40, 1930; Gray, Proc. Zool. Soc. London, Pt. 15, p. 137, 1847, type cited Murex anliquus; not of Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 394, 1927, type cited Buccinum undalum Linnaeus. Neptunea Bolten, Mus. Boltenianum, p. 115, 1798; Morch, Cat. Yoldi, p. 104, 1852; Cossmann, Ess. Palto. Comp., Vol. 4, p. 99, type Fusus anliquus L., pi. 4, fig. 15, 1901; Iredale, Proc. Malac. Soc. London, Vol. 14, p. 206, 1921; Stewart, Proc. Acad. Nat. Sci. PhQa., Vol. 78, p. 393, 1927; not "Neptunea Bolten" Dall. ' Joxirn. Wash. Acad. Sci., Vol. 9, p. 2, 1919. 2 Proc. U. S. Nat. Mus., Vol. 7, p. 525, 1884, as Stromhdla. * Proc. Calif. Acad. Sci., Vol. 5, p. 60, pi. 2, fig. 6, 1873, as Volutopsis beringi Midd., var. regularis. • Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 653 Not Tritonium Link, Beschreibung Naturalien-Sammlung der Universitat zu Rostock, Erste Abtheilung, p. 121, dated December 25, 1806. Chrysodomus Swainson, Treat. Malac, pp. 90, 308, 1840; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 234, 1847, type cited Fusus despedus; Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 521, 1902; Proc. Biol. Soc. Washington, Vol. 31, p. 137, 1918; Proc. U. S. Nat. Mus., Vol. 54, p. 214, 1918; Proc. Malac. Soc. London, Vol. 15, p. 36, 1922. ? Beringius Dall, Sci. Res. Expl. Alaska, pi. 2, legend, proofs sent to friends in 1879; Proc. U. S. Nat. Mus., Vol. 9, p. 304, 1886; Vol. 17, p. 710, 1894. Type (by subsequent designation, Cossmann, 1901), Murex antiquus Linnaeus. See plate 28, figure 10, of N. antiqua, and figures la, lb, of despecta, which is sometimes considered a variety of antiqua. Shell moderately large, elongate-ovate to subfusiform, ventricose; sculpture mostly spiral; outer lip usually simple ; anterior canal of moderate length, slightly curved. Geologic range: Cretaceous to Recent. Distribution: Cold and temperate waters. As Gray's designation of Murex antiquus for the type of Tritonium Miiller is per- fectly clear and vaUd, only Schumacher's rather questionable designation of type pre- vents the use of Tritonium for thi,s genus. If Schumacher's designations should not be accepted, Neptunea would fall as an exact synonym, having the same type as Tritonium. Chrysodomus, of which the type is "Fusus" despectus, cannot be used even as a section to include the tabulated species, since some varieties of Neptunea antiqua have tabulations well developed. This will be apparent to anyone examining a large series of N. antiqua. This species and several of its variants, including variety despecta, are beautifully figured by Dautzenberg and Fischer in the magnificent volume on the mollusks of the Hirondelle and Princess Alice Expedition in the North Sea.' Beringius Dall was supposed to have been estabU.shed in 1879, that name having been used in the explanation of a plate of which Dall had fifty proof copies distributed to conchologists, but its status is questionable as of that date. The type is conchologically similar to the N. lirata group. "Chrysodomus" giganteus Reagan, 1909, may, like Cymatium pacificum Dall, be a synonym of Neptunea lirata. In the CaUfornia Tertiary there are a number of species which have been improperly assigned to "Chrysodomus." It is often very difficult to assign fragmental or badly eroded specimens to the proper genus, and it would be better for all concerned if such specimens were described but not named until identifiable type material can be found. A number of forms have been named and placed in genera from which they will have to be removed eventually when better material shows more of the shell characters. The "Chrysodomus packardi" Nomland, which Hanna renamed "Chrysodomus f" prcenominata (new name for C. packardi Nomland, not C. packardi Weaver, 1916), appears to be a Tritonalia. "Chrysodomus" imperialis Dall has a low spire, a large pyriform body whorl, and other characteristics of Thais. It is represented by good specimens, but the writers have not been able to study them. Although it resembles somewhat N. satura or a Volutopsius, the partitions across its sutures suggest that it is more likely to belong in the Muricidce. "Chrysodomus" diegoensis Dall is a Kelletia. ' E^sultats des Campagnes Scientifiques accomplies sur son Yacht par Albert I, Prince de Monaco, Faso. 37, Monaco, Jline 15, 1912; see plates 1, 2, and 3. 654 San Diego Society or Natural History [Memoirs Neptunea (Neptunea) satura (Martyn) Buccirmm salurum Martyn, Figures of Nondescript Shells, table 2, pi. 47, 1784. Buccinum salurnum Martyn, Sherborn, Index Animalium, Sect. I, p. 871, 1902, error for salurum. Chrysodomus saturm Martyn, Dall, Jour. Wash. Acad. Sci., Vol. 9, no. I, p. 2, 1919; Bull. 112, U. S. Nat. Mus., p. 97, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 1, p. 232, pi. 27, figs. 3, 4 (not figs. I, 2), 1927. Type specimen: In the Hunter Collection, British Museum, fide Oldroyd. Type locality: King George's Sound. ? Pliocene: Late Pliocene of St. Faul Island, Pribilof group (Dall, 1919). Recent: Arctic Ocean from Point Barrow to Bering Strait; Plover Bay, south and east to Cape Douglas, Alaska. Dall reported! this species questionably in the Pleistocene on the south side of Her- schel Island, Yukon Territory. Neptunea (Neptunea) satura (Martyn) variety elatior (Middendorff) Tritonium elatior Middendorff, Sib. Reise, p. 225, pi. 10, fig. 3, 1848. Chrysodomus solutus elatior Middendorff, Dall, Jour. Wash. Acad. Sci., Vol. 9, p. 2, 1919. Chrysodomus satvrus elatior Middendorff, Dall, Bull. 112, U. S. Nat. Mus., p. 97, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol,, Vol. 2, Ft. 1, p. 233, 1927. Pliocene: Late Pliocene of St. George and St. Paul islands, Pribilof group (Dall, 1919). Recent: Norton Sound south to Unalashka, Alaska (DaU, 1921). Neptunea (Neptunea) satura (Martyn) variety tabularis (Dall) Chrysodomus saturus Martyn, new variety tabularis DaU, Proc. U. S. Nat. Mus., Vol. 56, pp. 323, 324, August 30, 1919. Chrysodomus saturus tabularis Dall, Jour. Wash. Acad. Sci., Vol. 9, p. 2, 1919; Bull. 112, U. S. Nat. Mus., p. 97, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 236, pi. 12, fig. 6, 1927. Type specimen: In the U. S. National Museum, No. 31,350. Type locality: Bering Sea, near Nunivak Island. Pliocene: Late Pliocene of St. Paul Island, Pribilof group (DaU, 1919). Recent: Pribilof and Nunivak Islands, Bering Sea (DaU, 1921). Neptunea (Neptunea) lirata (Martyn) Buccinum liratus Thomas Martyn, Figures of Nondescript SheUs, Vol. 2, table 2, pi. 43, 1784. Chrysodomus liratus Martyn, DaU, Washington Acad. Sci., "Alaska," Vol. 4, p. 121, 1904, reissued by Smithsonian Institution as the Harriman Alaska Series, Vol. 4, p. 121, 1910; U. S. Nat. Mus., Bull. 112, p. 98, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 237, pi. 11, figs. I, 3, pi. 20, figs. 1-4, 1927. Cymatium {Linalella) pacificum DaU, U. S. Geol. Surv., Prof. Paper 59, pi. 6, fig. 10, 1909; Amer. Jour. Sci., Ser. 5, Vol. 4, p. 312, 1922. ? "Chrysodomus stanloni Arnold," Reagan, Trans. Kansas Acad. Sci., Vol. 22, pi. 5, fig. 53, 1909, not of Arnold, ^rfe DaU, 1922. Cymatium pacificum DaU, Arnold and Hannibal, Proc. Amer. PhUos. Soc, Vol. 52, p. 590, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916; Howe, Univ. Calif. Publ. Geol, Vol. 14, p. 93 and table opposite, 1922. Shell rather large, ventricose, typically with a sloping tabulation on tlie upper part of the whorls and with strong, square spiral ridges separated by wide interspaces; varying into forms with low sculpture and with incipient interribs. Miocene: Miocene of Coos Bay, Oregon (as Cymatium pacificum DaU, 1909); Empire formation of Coos Bay region, Oregon (Arnold and Hannibal; Howe, as Cymatium pacificum DaU); Montesano forma- tion of western Washington (Howe, as Cymatium pacificum DaU). Pliocene: Coos conglomerate of Coos Bay, Oregon (Howe, as C. pacificum DaU). Pleistocene: Douglas Island, Juneau Harbor, Alaska (DaU, 1904). Recent: Icy Cape, Arctic Ocean, south to Japan on the west, to Puget Sound on the east; and off Point Finos, California, in 958 fathoms (DaU, 1921). 1 Canadian Arctic Expedition, Vol. 8. Pt. A, p. 26A, 1919. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 655 It is surprising that Dall should have redescribed this well-known and very charac- teristic northern Neptunea as a new Chjmatium. According to Dall, the type of Cymatium is Murex femorale, wliich is a gi'otesque, high-spired, heavy shell with immense varices, not at all similar to Neptunea lirata (Martyn). Mr. George Willett, who has collected extensively in Alaska, says that specimens of this species obtained between southeastern Alaska and Vancouver Island usually have much reduced spiral sculpture, while those occurring from the Alaskan Peninsula west- ward usually have stronger spiral sculpture. This is the Pacific analogue of the Atlantic A'^. decemcostata (Say). Neptunea (Neptunea) lirata (^Nlartyn) variety altispira Gabb Neptunea altispira Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, pp. 44, 45, 71, pi. 14, fig. 2, 1868-9; Cooper, Calif. St. Mining Bureau, Bull. 11, p. 83, 1896; .Arnold, in Eldridge and .Arnold, U. S. Geol. Survey, Bull. 309, p. 26, 1907; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 395, pi. 31, fig. 6, 1927. Shell not so prominently shouldered and higher spired than that of the typical variety. Type specimen: At the Academy of Natural Sciences of Philadelphia. Type locality: Eagle Prairie, Humboldt County; Pliocene. Pliocene: Eagle Prairie, Humboldt County (Gabb); "upper part of the Fernando formation northwest of Santa Paula" (Arnold); "Goat Mountain, near mouth of Adams Canyon," Ventura County (Cooper, as Pliocene, probably Las Posas zone. Pleistocene). Pleistocene: See Pliocene record. Recent: ? Neptunea (Neptunea) andersoni (Martin) Chrysodom-us andersoni Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 186, pi. 19, fig. 4, 1914. Pliocene: WOdcat formation of Eel River near Scotia, Humboldt County (Martin). This species is sculptured with rounded spiral cords, uniform in size except on and near the shoulder, where they are coarser and more widely spaced. The variety hawleyi has intercalary spirals, which are only sHghtly smaller than the primaries on the body whorl. The spiral cords of andersoni are not widely spaced as in N. lirata (Martyn). Neptunea (Neptunea) andersoni (Martin) variety hawle3ri (Carson) Plate 28, Figures 9a, 96, 9c Chrysodomus hawleyi Carson, BuE. So. Calif. Acad. Sci., Vol. 25, pt. 2, p. 55, pi. 2, fig. 3, May 31, 1926. Type specimen: In the type collection at Stanford University, No. 113. Type locality: Four miles west of Santa Barbara; upper PUocene. Pliocene: Four miles west of Santa Barbara, upper Pliocene (coU. by W. A. Hawley); S. D. S. N. H. loc. 218, upper Pliocene of Sulphur Canyon, east of South Mountain, Ventura County (coU. by Glenn E. Bader). Pleistocene: "Pliocene" of San Pedro, Los Angeles County (coU. by Delos .Arnold). Variety hawleyi differs from typical andersoni in the presence of intercalary spirals. On the type of hawleyi the intercalary spirals begin to appear on the second whorl from the body whorl and gradually grow in size until they are fully half as large as the primary ribs on the last whorl. The interspaces are flat bottomed. Both the typical form and Carson's variety are strongly shouldered, the latter having a heavy cord on the outer margin of the tabulation, and the next primary below being also accentuated. 656 San Diego Society of Natural History [ Memoirs Neptunea andersoni variety hawleyi appears to be restricted to the cold-water Santa Barbara horizon, uppermost Phocene, and to the Deadman Island "Pliocene" or Timms Point zone of the lower, cold-water Pleistocene. Neptunea (Neptunea) venturaensis (Waterfall) Chrysodomus venturaensis Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 87, pi. 5, figs. 1, 3, pi. 6, figs. 5, 6, April 6, 1929. Type specimen: In the collection at the University of California, No. .31,424. Type locality: About one mile above mouth of canyon at head of Kalorama Street, Ventura, California, Pliocene (Waterfall). Pliocene: In Kalorama Canyon at the tjrpe locality, also other localities in the upper Pico formation (Water- fall). ? Pleistocene: Two specimens from the Saugus Pleistocene near Ventura "resemble this form somewhat." (WaterfaU.) The type of this species, as figured by Waterfall (pi. 6, fig. 6), has no tabulation or shoulder on the later whorls, while the paratype (pi. 5, fig. 3) is strongly shouldered. The sculpturing, however, is the same on both specimens, and it is probable that they repre- sent variants of the one species. The paratype, mentioned above, differs from iV. andersoni variety haivleyi (Carson) in the lack of interspaces between the intercalary and the primary spiral cords, Carson's form having flat interspaces between all the spirals. N. venturaensis shows a tendency to have alternate primaries accentuated, producing spiral ribs of three different sizes. This tendency is characteristic of the Neptuneidce. As several of these forms are obviously closely related, more specimens may show that they should be grouped into fewer species. Neptunea venturaensis (Waterfall) appears to be restricted to the cold-water upper Pliocene and possibly the lower Pleistocene. Neptunea (Neptunea) leffingwelli (Dall) Chrysodomus leffingwelli DaU, U. S. Geol. Surv., Prof. Paper 125-C, p. 28, pi. 5, fig. 11, January 27, 1920. Type specimen: In the U. S. National Museum. Type locality: Colville River, forty miles from the Arctic coast; Pliocene. Pliocene: At the type locality (Dall). This species is tabulated and has spiral ridges and widely spaced axial ribs. Dall states that some specimens have the sculpture more or less obsolete. Neptunea (Neptunea) clarki (Meek) Chrysodomus clarki Meek, Univ. Calif. Publ. Geol., Vol. 14, p. 417, pi. 79, figs, la-b, November 23, 1923. Type specimen: In the collection at the University of California, No. 30,593. Type locality: Skull Cliff beds, Peard Bay, Arctic Alaska; Pleistocene. Shape like that of lirata, but with one hirge and one small spiral cord per whorl, the larger one nodose. Pleistocene: Type locality (Meek). Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 657 Neptunea (Neptunea) pribilofifensis (Dall) Chnjsodomus pribiloffensis Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 323, August 30, 1919; Journ. Wash. Acad. Sci., Vol. 9, no. 1, p. 2, 1919; U. S. Nat. Mus., Bull. 112, p. 97, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol 2, Ft. 1, p. 231, pi. 21, fig. 4, 1927. Pliocene: Late Pliocene of St. Paul Island, Pribilof Islands (Dall, 1919). Recent: Pribilof Islands to Kodiak Island, Alaska, and the Queen Charlotte Islands, British Columbia; also Japan (Dall, 1921). Neptunea (Neptunea) soluta (Hermann) Bucdnum solulum J. Hermann, Naturforscher, Vol. 16, p. 53, pi. 2, figs. 3, 4, 1781, not of Dillw3Ti, 1817. Chrysodomus heros Gray, Proc. Zool. Soc. London, Vol. 18, p. 15, Nov. 12, 1850. Neptunea despecta Linnaeus variety /ci(7iJca(o Gray, Tryon, Man. Conch., Vol. 3, p. 116, pi. 45, figs. 251, 252, 253, pi. 46, figs. 255, 256, 1881. Chrysodomus solutus Hermann, Dall, Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919; Bull. 112, U. S. Nat. Mus., p. 97, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 236, 1927. Pliocene: Upper Pliocene of St. George and St. Paul Island, Pribilof Islands (Dall, 1919). Recent: Mackenzie River delta west to Point Barrow and south to Bristol Bay, Bering Sea (Dall, 1921). Neptunea (Neptunea) soluta (Hermann) variety cordata (Dall) "Chrysodomus solutus cordalus DaU, n. var.," Jour. Wash. Acad. Sci., Vol. 9, no. 1, p. 2, 1919. Pliocene: Late Pliocene of St. George Island, Pribilof Islands (DaU). This variety is neither described nor figured in the reference given above, and the present writers have seen nothing to indicate its characters. It is probably a nude name Neptunea (Neptunea) borealis (Philippi) Fusus borealis Philippi, Abbild. Beschreib., Vol. 3, p. 118, Fasus, pi. 5, fig. 2, 1850. Chrysodomus borealis Philippi, Dall, Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919; Dall, U. S. Nat. Mus., Bull. 112, p. 97, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 231, 1927. Shell without spiral sculpture, but with prominent nodes on the edge of the tabulation. Pliocene: Late Pliocene of St. George and St. Paul islands, Pribilof Islands (DaU, 1919). Recent: Arctic Ocean to Avacha Bay, Kamchatka, the Aleutian Islands, and eastward to the Shumagin Islands, Alaska; 14 to 110 fathoms (Dall, 1921). Subgenus ANCISTROLEPIS Dall, 1S94 Anristrolepis DaU, Proc. U. S. Nat. Mus., Vol. 17, p. 709, 1894. Type (by original designation), Chrysodomus eucosmius Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 187, 1891, figured in Vol. 17, pi. 29, fig. 7, 1894; + Ancistrolepis calif ornicus Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 313, 1919; Vol. 66, Art. 17, p. 3, pi. 3, fig. 9, 1925; Pacific coast. Recent. Shell Buccmoid, with a short, twisted canal; operculum straight, claw shaped, with apical nucleus. (After Dall.) Ancistrolepis is distinguished from Neptunea by its short, wide anterior canal. The columella is strongly incurved in the middle. The type species has prominent, widelj'- spaced spiral ribs. The same is true of the type of Beringius Dall, 1886, though the latter has a higher spire. Perhaps Ancistrolepis should be considered a section or synonym of Beringi^is. The species magna (Dall), the name of which, if preoccupied, might be replaced by unica (Pilsbry), has commonly been referred to this subgenus. However, it does not greatly resemble eucosmia, to judge from the figures of the latter, and seems to be more closely related to the other sections of Sulcosipho. 658 San Diego Society of Natural History [Memoirs Subgenus SULCOSIPHO Dall, 1916 Sulcosipho Dall, Proc. Biol. Soc. Washington, Vol. 29, p. 7, January 25, 1916, type Chrysodomus tabulatus Baird; Proc. U. S. Nat. Mus., Vol. 54, p. 215, April 5, 191S. Type (by original designation), Chrysodomus tabulatus Baird. "Shell like Chrysodomus but more slender and elongate and with the whorl in front of the suture conspicuously widely sulcate or tabulate, the nucleus inflated and slightly oblique, the color whitish." (DaU, 1918.) Section Sulcosipho, s. s. Shell with moderately elongate aperture, produced columella, and well-developed spiral sculp- ture of numerous spiral cords. This section is connected with typical Neptunea through the strongly tabulated species postplanata and andersoni. On the other hand, lawsoni appears to be a step toward scotiaensis, which is much like pericochlion, a close relative of the type of Japelion. Neptunea (Sulcosipho) tabulata (Baird) Chrysodortms tabulatus Baird, Proc. Zool. Soc. London for 1863, p. 66, 1863; Cooper, 7th Ann. Rept., Calif. St. Min- eralogist, p. 235, 1888; DaU, Proc. U. S. Nat. Mus., Vol. 24, p. 524, pi. 36, fig. 5, 1902; Arnold, Mem. CaUf. Acad. Sci., Vol. 3, p. 228, pi. 7, fig. 6, 1903; Weaver, Univ. Calif. Publ. Geol., Vol. 5, p. 264, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 593, 594, 596, 1913; Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 189, pi. 20, fig. 2, 1914; Moody, Vol. 10, p. 43, 1916; DaU, U. S. Nat. Mus., BuU. 112, p. 96, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 227, pi. 4, fig. 5, pi. 18, fig. 4, 1927; WaterfaU, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Chrysodomus bairdi DaU, U. S. Geol. Surv., Prof. Paper 59, p. 43, pi. 2, fig. 4, 1909; Arnold and Hannibal, Proc. Amer. PhUos. Soc, Vol. 52, p. 590, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 32, 1916; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 240, 1916; Howe, Vol. 14, p. 93, 1922. BucHnum ? stocki Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 101, pi. 8, figs. 2, 4, 1922. Type specimens: Of tabulata, in the British Museum; of bairdi, in the U. S. National Museum. Type localities: Of tabulata, Vancouver Island; of bairdi, Coos Bay, Oregon, Empire formation, upper Miocene. Miocene: Empire formation, upper Miocene, at Coos Bay, Oregon (DaU, as bairdi); upper Miocene on Sylvia Creek, western Washington (Weaver, 1916); ? upper San Pablo formation and Santa Margarita formation, upper Miocene of middle California (Weaver, 1909) ; Bear River, upper Miocene (now thought to be lower Pliocene), Humboldt County, California (Martin, 1916). Pliocene: Pliocene of Eagle Prairie, Humboldt County; Twelve Mile House, San Mateo County; San Fer- nando, Los Angeles County (Cooper) ; Merced formation of San Francisco peninsula and Eel River formation of Eel River (Arnold and Hannibal); upper WUdcat formation, northern California (Howe); Elk River formation north of mouth of Elk River, Port Orford, Oregon (Arnold and Han- nibal) ; Fernando formation of Los Angeles (Moody) ; Santa Barbara (Cooper) ; Pico near Ventura (WaterfaU). Pleistocene: "Pliocene" of Deadman Island; lower San Pedro series of Deadman Island and San Pedro; old irrigation ditch north of Ventura (Arnold); Saugus formation near Ventura (WaterfaU). Recent: British Columbia and south to San Diego in 46 to 218 fathoms (DaU, 1921). This species, the type of Sulcosipho, is characterized by the rather uniform spiral ribbing, the prominent tabulation bordered by a raised ridge on the upper part of each whorl, and the rather wide, strong anterior canal. Chrysodomus bairdi Dall and "Bucci- num ?" stocki Howe are based upon imperfect, decorticated specimens. Volume I ] PLIOCENE AND PLEISTOCENE MOLLTJSCA OF CALIFORNIA 659 Neptunea (Sulcosipho) tabulata (Baird) variety colmaensis (Martin) Chrysodoimis tatnilatus var. cobiuicnsis Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 188, pi. 20, fig. 1, August 6, 1914; Waterfall, Vol. IS, table opp. p. 78, 1929. Type specimen: At the University of California, Berkeley. Type locality: In the bed of Twelve Mile Creek, one and a quarter miles south of Baden Station, San Mateo County; Pliocene. Pliocene: Merced formation south of San Francisco (Martin). Pleistocene: Saugus formation, near Ventura (Waterfall). The variety colmaensis is broader in proportion to height than the typical tabulata. Neptunea (? Sulcosipho) postplanata (Dall) Chrysodomm poslplanatus Dall, U. S. Geol. Surv., Prof. Paper 59, p. 43, pi. 7, fig. 5, April 2, 1909; Amer. Jour. Sci., Ser. 5, Vol. 4, p. 309, 1922. ? Chrysodonms gettysburgensis Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 190, pi. 3, fig. 26, Nov. 24, 1909; Dall, Amer. Jour. Sci., Ser. 5, Vol. 4, p. 309, 1922. Type specimens: Of postplanata, in the U. S. National Museum, No. 107,781; of gettysbergensis, also in the U. S. National Museum. Type localities: Of postplanata, Bogachiel River, one mile above its mouth, Clallam County, Washington, upper Miocene; of gettysburgensis, near Gettysburg, Washington, upper Miocene. Upper Miocene: At the type localities. From Dall's figure, N. postplanata appears to be similar to N. tabulata but has a lower spire and broader body whorl. It also lacks the strength of spiral ribbing (perhaps due to erosion) of tabulata and its variety colmaensis. Ball's type measures 90 mm. in height and 50 mm. in diameter. Perhaps the variety colmaensis belongs here. Perhaps it is an older name for andersoni or hawleyi. Neptunea (? Sulcosipho) lawsoni (Martin) Chrysodonius lawsoni Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 184, pi. 19, fig. 1, 1914. Pliocene: W^Odeat formation of Eel River, three-quarters of a mile north of Scotia, Humboldt County, north- ern California (Martin). This species is strongly tabulated, like N. tabulata (Baird), but is more elongate. It is probably very closely related. Section Japelion Dall, 1916 Japelion Dall, Proc. Biol. Soc. Wash., Vol. 29, p. 8, Jan. 2.5, 1916; Proc. U. S. Nat. Mus., Vol. 54, p. 225, 1918. Type (by original designation), Buccinum hirasei Pilsbry, Proc. Acad. Nat. Sci. Phila. for 1901 (Vol. 53), p. 391, pi. 20, fig. 22, Aug. 16, 1901. Shell like that of Sulcosipho but with the spiral sculpture nearly obsolete, the columella shorter, and the aperture rounded as in Buccinum. Dall stated that the similarity between pericochlion^ (Schrenck) and hirasei is a remarkable case of parallel development. However, good specimens in the Golisch Collection at the California Institute of Technology, which agree closely with the figures ' See Neptunea pericochlion Schrenck, Tryon, Man. Conch., Ser. 1. Vol. 3, p. 121, pi. 49, fig. 2S4, 1881, and Chrysodomus pericochlion Schrenck, PUsbry, Proc. Acad. Nat. Sci. Phila., Vol. 53, p. 391, pi. 20, fig. 23, 1901. 660 San Diego Society of Natural History [ Memoirs of these species by Pilsbry, show unmistakably that the two are very closely related. They agree so closely in every particular, except in the length of the columella and aper- ture, that it does not seem reasonable to attribute their similarity to the coincidences of parallel development. It is even probable that the two forms are varieties of a single species, for in a series of specimens each should be expected to vary somewhat, and it would not require much variation to bridge the gap. As Tryon apparently observed, the chief difference between pericochlion and tabulata is in the strength of the sculpture, and the present writers think that this difference is probably not of more than sectional significance. The specimen of hirasei in the Golisch Collection has an operculum with an apical nucleus like that of tabulata. Neptunea (Sulcosipho) scotiaensis (Martin) Chrysodorrms scoHncnsis Martin, Univ. Calif. Publ. GeoL, Vol. 8, p. 186, pi. 20, figs. Za-h, August 6, 1914. Pliocene: Wildcat series of Eel River, three-quarters of a mile north of Scotia, Humboldt County (Martin) . This species is likewise closely similar in general appearance to tabulata. Section Clinopegma, new section Type: Buccinum unicum Pilsbry. Shell much like that of Japelion but with the posterior tabulation sloping and marked on the angle by a ridge; sometimes the tabulation iliviclcd into two concave parts by another ridge, Uke the one on the outer angle. Ancistrolepis might be thought of as a somewhat similar development, with the angulations and ridges continuing all the way down the side of the whorl; but the con- nection between Ancistrolepis and Clinopegma does not seem as real as the connection between Japelion or Sulcosipho and Clinopegma. Ancistrolepis seems more like the young of such species as N. lirata, or perhaps a degenerate relative. On the other hand, Japelion and Clinopegma grade into Colus by the loss of the angulation or by appressing it to the suture. Neptunea (Sulcosipho) magna (Dall) Chrysodomus (Annstrolepis) magnus Dall, Proc. U. S. Nat. Mus., Vol. 17, p. 709, pi. 29, fig. 5, 1895. Buccinum unicum PUsbry, Proc. Acad. Nat. Sci. Phila., Vol. 57 (for 1905), p. 102, AprU 8, 1905; Vol. 59 (for 1907), p. 244, pi. 20, fig. 7, 1907. Chrysodonms (Ancistrolepis) unicus Pilsbry, Dall, Smithsonian Misc. Coll., Vol. 50, Pt. 2, p. 157, 1907. Ancistrolepis 7nagnus Dall, Bull. 112, U. S. Nat. Mus., p. 92, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 20.3, pi. 25, fig. 5, 1927. Recent: Okhotsk and Bering seas (Dall); Japan (Pilsbry). The typical form of this species has a shorter spire than the variety stantotii, and the same seems to be true to a less extent of the form described by Pilsbry. However, a specimen in the Oldroyd Collection at Stanford University from Japan has a higher spire than the Recent forms that have been figured. This specimen should probably be assigned to the variety damon (Dall),' which may be an older name for the variety stantoni. The variety damon has, if anything, a higher spire than stantoni. The form decora,^ more recently described by Dall, seems to be based on a young specimen from the Japan Sea with stronger spiral sculpture. The oldest name of all that has been 1 Chrysodomua {Ancistrolepis) damon Dall, Smithsonian Misc. Coll., Vol. 50. p. 157, 1907; Ancistrolepis damon Dall, Proc. U. S. Nat. .Mus., Vol. 66, Art. 17, p. 3, pi. 34, fig. 5, 1925. » Ancistrolepis decora Dall, Proc. U. S. Nat. Mus.. Vol. 66, Art. 17, p. 3, pi. 35. fig. 10, 1925. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 661 applied to a form with the general appearance of Clinopegma is Buccinum viridum Dall.' This name is based upon a small, short, low-spired, apparently immature individual, hke magna but with a Buccinum operculum. It seems probable that this species belongs to the group also, in spite of its operculum. It might even be a young variant of m,agna. The many cases of so-called parallel development between the Neptuneidw and the Buc- cinido' provide strong evidence that the separation of the Neptuneidw from the Buc- cinidcF is artificial. This separation is based upon the pure assumption that opercula are of primary importance in classification. Neptunea (Sulcosipho) magna (Dall) variety stantoni (Arnold) Chrysodomus slantoni Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 386, pi. 37, fig. 4, August 8, 1908; not "Chrysodomus stantoni Arnold," Reagan, 1909, fide Dall, Amer. Jour. Sci., Ser. 5, Vol. 4, p. 312, 1922. Shell large, whorls ventricose, with a strongly sulcate suture and a sloping tabulation bordered by a spiral ridge; base of body whorl with a few faint, wide spiral cords. Altitude, 90 mm. (incom- plete specimen) ; width, 45 mm. Type specimen: In the U. S. National Museum, No. 165,475. Type locality: Purisima Rock, seven-eighths of a mile east of Ano Nuevo Point, San Mateo County; Purisima formation, Pliocene. Pliocene: At the type locality; sea cliffs between mouths of Tunitas and Pescadero Creeks, Purisima forma- tion- near mouth of Ano Nuevo Creek, San Mateo County; sea cliff west of Capitola, Santa Cruz County, Merced formation (^^nold). The variety is so similar to Recent specimens of unica that it can be distinguished only by its greater size and the subdued condition of the spiral sculpture on the base of the body whorl (which may be due to erosion). Subgenus COLUS BoUen, 1798 Coins Bolten, Mus. Boltenianum, p. 117, 1798; Dall, Journ. Conch., Vol. 11, no. 10, p. 294, 1906; Proc. U. S. Nat. Mus., Vol. 54, p. 216, 1918. Tritonofusus (Beck ?), Deutscher Naturforscher und Aerzte, Amtlicher Bericht uber die 24 Versammlung in KJel, September, 1846, p. 114, 1847; Herrmannsen, Indicis Gen. Malac, Vol. 2, p. 611, 1849; Dall, Proc. U. S. Nat. Mus., Vol. 24, pp. 520, 522, 1902. Sipho Klein, of various authors. Tijpe (by subsequent designation, Dall, 1906), Murex islandicus Gmelin, Syst. Nat., Ed. 13, p. 3555, 1790, = ? Murex islandicus G. Mohr, Island Nat., p. 136, 1786; = Murex Cornells Linnsus, Syst. Nat., Ed. 10, p. 754, 1758; Ed. 12, p. 1224, 1767; Gmelin, Ed. 13, p. 3552, 1790; Fusus isla^idicus Chemnitz, Neues Syst. Conch. Cab., Vol. 4, pi. 141, figs. 1312, 1313, 1780; Colus islandicus Bolten, Mus. Boltenianum, p. 117, 1798; Fusus islandicus Lamarck, Ency. Meth., pi. 429, fig. 2, 1816; Crouch, Lamk. Conch., pi. 17, fig. 8, IS27; Murex corneus, Dillwyn, Cat., Vol. 2, p. 723, 1817; Wood, Ind. Test., pi. 27, fig. 107, 1818; Fusus islandicus Martini, Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 5, p. 37, pi. 7, figs. 2 (not pi. 15, figs. 2), 1840; Fusus corneus Linnseus, Deshayes in Lamarck, Hist. Nat. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 9, p. 450, 1843; Recent, Iceland to Ireland; much like stimpsoni of the east coast of North America. Shell like that of Neptunea antiqua but usually smaller, more slender, with less mflated whorls and shorter aperture. I Buccinum viridum Dall, Proc. U. S. Nat. Mus., Vol. 12, p. 320, pi. 6, fig. 9, 1889; also figured by Keep, West Araer. Shells, p. 172, fig. le.'i, 1904. 662 San Diego Society of Natural History [Memoirs Deshayes remarks that the type of this subgenus is closely related to N. antiqua. It is a large northern shell, large for the group. Some of its smaller relatives go south- ward in deep water. They are classified in the section Anomalosipho. Perhaps further research will disclose older names for some of the sections in this family. Neptunea (Colus) eurekaensis (Martin) Chrysodomus eurekaensis Martin, Univ. Calif. Publ. Geol., Vol. S, p. 185, pi. 21, figs, la-b, 1914. Shell elongate, body whorl smooth, upper whorls of spire with small spiral cords; a slight con- striction below the suture. Type specimen, 86 mm. long and 45 mm. in diameter. Type specimen: At the University of California. Type locality: Near Scotia, Humboldt County, northern California. Pliocene: At the type locality. This species is like "Chrysodomus" ithius Dall but larger. Neptunea (Colus) purisimaensis (Martin) Chrysodomus purisimaensis Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 187, pi. 19, fig. 2, 1914. Shell elongate, high spired, not tabulated. Type specimen, 100 mm. in length (incomplete) and 50 mm. ia diameter. Type specimen: At the University of California. Type locality: Ano Nuevo Bay, San Mateo County; Pliocene. Pliocene: Purisima formation of Ano Nuevo Bay, San Mateo County (Martin). This species is similar to the last. Section Anomalosipho Dautzenberg and Fischer, 1912 Anomalosipho Dautzenberg and Fischer, Res. Camp Sci. Albert I, Prince de Monaco, Vol. 37, p. 99, 1912; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 218, 1918. Latisipho Dall, Proc. Biol. Soc. Washington, Vol. 29, p. 7, 1916; Proc. U. S. Nat. Mus., Vol. 54, p. 217, 1918, type (by original designation), Chrysodomus hypolispus Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 188, 1891 ; Vol. 17, pi. 27, fig. 1, 1894. Type (fide Dall, 1916, 191S), Sipho verkriizeni Dautzenberg and Fischer (not Kobelt), = Colus dautzenbergii Dall. Shell smaller and more delicate, sometimes with a relatively shorter columella and more rounded aperture. Dall's section has a more curving columella and anterior canal. In spite of Dall's opinion, perhaps the true verkriizeni should be taken as type of Anomalosipho. It prob- ably belongs to the same group but seems to lack the spiral grooves. Neptunea (Colus) halibrecta (Dall) Chrysodomus (Sipho) halibrcctus Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 188, 1891; Vol. 17, p. 708, pi, 29, fig. 9, 1894. Chrysodomus halibrectus Dall, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 239, 1916. Colus {Latisipho) halibreclus Dall, U. S. Nat. Mus., Bull. 112, p. 96, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 226, pi. 25, fig. 9, 1927. Shell elongate, with fine spiral striae; length 35 mm., breadth, 13.5 mm. Pliocene: Upper division of Wildcat series, northern California (Martin). Recent: Southern Bering Sea, near Unalaska Island, 351 to 399 fathoms (Dall, 1921). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 663 Neptunea (Colus) jordani (Dall) Plate 28, Figure 11 Trilonofusvs jordani Dall, Proc. U. S. Nat. Mus., Vol. 45, p. 588, June 11, 1913. Colus {Lalisipho) jordani Dall, Bull. 112, U. S. Nat. Mus., p. 96, pi. 12, fig. 7, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 225, pi. 16, fig. 5, 1927. Type specimen: In the U. S. National Museum. Type locality: Sucia Island, Gulf of Georgia; Recent. Pleistocene: Elk River formation, north of the mouth of Elk River, Port Orford, Oregon (.specimen in the collection at Stanford University). Recent: Bering Sea, 70 to 100 fathoms; British Columbia, 67 to 142 fathoms; Monterey Bay, California, 633 fathoms. This species recalls Buccinmn strigillatuin but is more elongate, with a different aperture. Neptunea (Colus) riversi (Martin) Trilonofusus riversi Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 190, pi. 21, fig. 2, August 6, 1914. Colus (Latisipho) riversi Martin, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, pp. 78, 82, 1929. Shell like that of jordani but with a longer anterior canal. Type specimen: At the California Academy of Sciences. Type locality: Timms Point, San Pedro, Los Angeles County; Pleistocene. Pliocene: "Lower Pico" near Ventura, middle Pliocene (Waterfall). Pleistocene: Timms Point, San Pedro, Los Angeles County (Martin). Neptunea (Colus) aphela (Dall) Chrijsodomus aphelus Dall, Proc. U. S. Nat. Mus., Vol. 12, p. 323, pi. 6, fig. 7, 1889; Rivers, Bull. So. Calif. Acad. Sci., Vol. 3, no. 5, p. 71, May 24, 1904. Colus (Latisipho) aphelus Dall, Bull. 112, U. S. Nat. Mus., p. 96, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 225, pi. 13, fig. 3, 1927. Type locality: In 414 fathoms off the coast of Santa Barbara County, California. ,' Lower Pleistocene: "Pliocene" of Santa Monica fRivers). Rea'tU: Chirikoff Island, Alaska, to San Diego, California, 290 to 626 fathoms (Dall, 1921). Neptunea (Colus) merriami (Rivers) Chrysodomus merriami Rivers, Bull. So. Calif. Acad. Sci., Vol. 3, no. 5, p. 70, May 24, 1904. "Shell bucciniform; whorls eight; nucleus eroded; incremental and fine lines appear as soon as growth liegms which mcrease in regular ratio until the body whorl show ridges and appressed lines that gage six to a mm. Apex not depressed as it gages 20 mm.; the whorls are strongly rounded; sutures deeply impressed; bodywhorl 25 mm. long, much inflated; outer lip not thickened but has a bulging inflation turning inwards; the edge being entire. The colunmella being hid in the matrix but from several fragmentary examples; the columnella is short, twisted; channel wide; aperture very wide. "This shell was fomid in the same deposit as C. aphelus Dall and C. griseus Dall. "Geological formation : Pliocenl ; Santa Monica Range. ' ' (Rivers. — The spelUng and punctuation are as in the original, which appears to have been printed from rough notes and not proof-read.) Type locality: Rivers describes the locality as follows: "The fossils occur in a silty formation in which remains of marine and terrestrial flora abound. The elevation from sea level of these strata varies from a few feet up to seventy or a hundred feet above. The height or depth of these strata carries no geological value but it is their position and what 664 San Diego Society of Natural History [ Memoirs they contain that yield their natural worth ; these strata dip strongly to the southwest at various angles and in places tilted to the perpendicular. These fossUs therefore may have enjoyed at one time a depth of 414 fathoms, particularly so as the deposits dip under a hundred feet of nearly horizontal Pleistocene." ? Lower Pleistocene: "Pliocene" of the Santa Monica Range (Rivers). This species is probably represented in the living fauna, but it is difficult to determine without material what it is. Section Plicifusus Dall, 1902 PUcifvsvs Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 523, 1902, Vol. 54, p. 219, 1918. Parasipho Dautzenberg and Fischer, Res. Camp. Sci., Albert I, Prince de Monaco, Pt. 37, pp. 82, 100, "type Sipho kroyeri MoUer," 1912. Type (by original designation), Fusus kroyeri MoUer, Naturhist. Tidsskrift, Vol. 4, Pt. 1, p. 88, 1842; Index Moll. Groenl., p. 15, 1842; figured by Dautzenberg and Fischer, op. cit., pi. 4, figs. 6, 7, 1912, also by Tryon, Man. Conch., Ser. 1, Vol. 3, p. 130, pi. 53, figs. 233-236, 1881. Shell solid, usually with developed axial ribs and more feeble spiral sculpture, the aperture ex- panded and with a wide insmuation behind on the outer lip; canal usually short and wide, nearly straight. (After Dall, 1902.) The type of Plicifiisus is a circumboreal species which extends west in the Arctic Ocean to Point Barrow. Buccinuni cretaceus Reeve may be a synonym. N. kroyeri (Moller) is very similar to the type of Colus except that it has axial ribs on the early whorls. Neptunea (Colus) arctica (Phihppi) Fusils arclicus Philippi, Abbild. Beschreib. Conchyl., Vol. 3, p. 119, pi. 5, fig. 5, 1850. Plicifusus arctic-US Philippi, Dall, Journ. Washington Acad. Sci., Vol. 9, p. 2, 1919; U. S. Nat. Mus., Bull. 112, p. 93, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 207, 1927. Shell fusiform, with numerous small axial plications. Pliocene: Late Pliocene of St. George Island, Pribilof Islands (Dall, 1919). Recent: Arctic Ocean, Bering Sea, Aleutians to Shumagin Islands, Alaska; circumboreal. Section Latifusus Dall, 1916 Lalifusus Dall, Proc. Biol. Soc. Wash., Vol. 29, p. 8, 1916. Type (by original designation), Chrysodomus griseus Dall. Dall says of this section that it is the Buccinoid phase of Plicifusus, as Latisipho is of Colus. Neptunea (Colus) grisea (Dall) Chrysodomus griseus Dall, Proc. U. S. Nat. Mus., Vol. 12, p. 322, pi. 5, fig. 6, 1889; Rivers, Bull. So. Calif. Acad. Sci., Vol. 3, no. 5, p. 72, May 24, 1904. Plicifusus (Retifusus) griseus Dall, Bull. 112, U. S. Nat. Mus., p. 93, 1921 ; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 210, 1927. Type locality: With N. aphela. f Lower Pleistocene: "Pliocene" of Santa Monica Range (Rivers). Recent: Bering Sea (27 fathoms) to San Diego, California (636 fathoms), (Dall, 1921). In spite of the differences, the similarity of the distribution and the association of this form with aphela suggest that it is but a variety of that species, just as the type of Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 665 Plicifusus may be a variety of the type of Coins. The subdivisions of Coins are still very artificial, and a number of older names, such as those of Morch and Cossmann, need to be given more serious attention. Probably some of Dall's very recent names will fall into synonymy. Genus EXILIOIDEA, new genus "Exilia Conrad" of Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 221, 1918, in part; of various Pacific coast collectors and authors; not of Conrad, Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 4, p. 291, 1860; nor of Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 418, 1927, a genus of Turridse; nor Exilia Mulsant, 1863, Coleoptera. Type, Chrysodomus rectirostris Carpenter. Shell elongate, very slender, with numerous whorls, chrysodomoid nucleus, and a straight canal; periostracum conspicuous, polished ; sculpture of numerous fine flexuous axial ribs and spiral stria- tion; aperture small, simple, not lirate ^vithin, outer lip thin, sharp, not reflected; inner lip and pillar smooth, without plications or denticles of any sort; operculum long, slightly arcuate, with apical nucleus. (Dall, 1918, description of "Exilia.") Stewart (1927) has pointed out that the type of Exilia Conrad has a small anal notch, which suggests that it belongs to the Tnrridce. The Pacific coast Pleistocene to Recent species which Dall called Exilia rectirostris (Carpenter) has no indication of a Turrid notch and is probably not related to typical Exilia of the Texas Eocene. We have therefore proposed for the Pacific "Exilia" rectirostris the new generic name Exilioidea, and have placed it tentatively in the Neptuneidce, admitting, however, that it appears out of place in that family. Exilioidea rectirostris (Carpenter) Plate 28, Figure 5 Chrysodomus rectirostris Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 603 (nude name), p. 664 (brief descrip- tion), 1864; Proc. Acad. Nat. Sci. Phila., for 186.5, p. 64, August, 1865; Tryon, Man. Conch., Ser. 1, Vol. 2, p. 131, pi. 53, fig. 348, 1881; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 228, pi. 7, fig. 7, 1903; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 221, 1918. Trilonofusus (Plicifusus) rectirostris Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 525, pi. 34, fig. 2, 1902. Exilia rectirostris Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 92, 1921; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 90, pi. 19, fig. 2, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 206, pi. 6, fig. 7, pi. 28, fig. 2, 1927. Type specimen: In the U. S. National Museum, No. 4815. Type locality: Puget Sound; Recent. Pleistocene: "Rare in the Pliocene and lower San Pedro series at Deadman Island, and in the upper San Pedro series at Crawfish George's" (Arnold). Recent: Behm Canal, Alaska, to Cape San Quintin, Lower California, Mexico (Dall, 1921). The series of specimens of this species which we have examined shows no indication of an anal notch such as is characteristic of the Turridce, to which the typical Exilia probably belongs.' As there seems to be no evidence of close relationship between the 1 It is true that some forms belonging to the Turridx show very faint anal notches or even none at all, such as Daphnella, Beta, Mitro- morpha, some species of Lora, etc.. and the genus Priscofusus, doubtfully referred to the Turridse, has only a broad bending back of the growth lines on the outer lip, after the analogy of some species of Surculites. The case of Priscofusus is similar to that of Exilioidea, and for the time being the family relationships must remain uncertain. The type of Exilia (type by monotypy, E. peroTacilis Conrad, Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 4, p. 291, pi. 47, fig. 34, 1860, also figured by Harris, Bulls. Amcr. Paleo., Vol. 1, p. 204, pi. 9, fig. 1, 1S96; Eocene of Texas) has, according to Stewart, "a faint notch in the outer lip. . . which is probably a shallow anal sulcus." The true Exilia has a slender, elongate shell, consisting of numerous whorls; the anterior canal is long and straight; and the columella is smooth. The two oblique columellar plaits attributed to it by Cossmann are thought to have been introduced as an error caused by a specific misidentification. Exilia. because of its comparatively early date, 1860, should have been included in the treatment of the Tvrridse: but, probably like a number of other names, it was overlooked because it had been assigned to another family. It probably belongs in the table close to Pleurofusia or Moniliopsis. 666 San Diego Society of Natural History [ Memoies type of Exilia, which is an Eocene shell of Texas, and the west American "Exilia" rectiros- tris, aside from a superficial resemblance, we have placed the latter in the new genus Exilioidea. Recent specimens of this species show variation in the strength of the axial ribs, but all are rather uniform in shape. Mr. George Willett, of the Los Angeles Museum, col- lected this species by dredging in 50 fathoms off Forrester Island, Alaska, but did not find it in the straits. Genus LIOMESUS Stimpson, 1865 Liomesus Stimpson, Canadian Naturalist and Geologist, New Series, Vol. 2, p. 366, October, 1865, tjqje Buccinum dalei; Dall, Bull. Mus. Comp. Zool., Vol. 18, pt. 2, p. 176, 1889; Cossmann, Ann. Soc. Roy. Malac. Belgique, Vol. 24 (Ser. 4, Vol. 4), p. 141, 1889. Bucdnopsis JeHnes, Brit. Conch., Vol. 4, p. 297, 1867. Type (by original designation), Buccinum dalei J. de C. Sowerby, Mineral Conch. Gt. Brit., Vol. 5, p. 139, pi. 486, figs. 1, 2, 1829; figured also by Forbes and Hanley, Hist. Brit. Moll., Vol. 3, p. 408, pi. 109, figs. 1, 2, 1851; Recent, coasts of Greenland to British Isles; also Pliocene of the Coralline Crag and Red Crag of England. Shell of moderate size, bucciiiif orm ; with spiral striations or threads; pillar short, twisted; outer lip thickened, not reflected; operculum with an apical nucleus; periostracum conspicuous. This genus is similar to Buccinuvi but has an operculum with an apical nucleus. Liomesus ovoides (Middendorff) variety canaliculatus (Dall) Buccinopsis canalicvlala Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 252, Feb. 26, 1874. Buccinopsis canaliculatus Dall, Kobelt, Martini and Chemnitz, Conch. Cab., Ed. 2, Vol. 3, Buccinum., p. 102, pi. 88, fig. 2, 1883. Liomesus canaKculalm Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 531, pi. 38, fig. 2, 1902; Harmer, Mon. Palseo. Soc, Vol. 67, Plio. MoU. Gt. Brit., Vol. 1, p. 115, 1914. JAomesus ovoides caiwliculatus Dall, BuU. 112, U. S. Nat. Mus., p. 91, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 198, pi. 2, fig. 23, 1927. Type specimen: In the U. S. National Museum. Type locality: Cape Espenberg, Arctic Ocean. Pliocene: Butleyan Crag, lower part of upper Pliocene of England; Pliocene of Iceland (Harmer); etc. Recent: Icy Cape, Arctic Ocean, to Shumagin Islands. This is a compact species with a very short, wide anterior canal and sculpture of fine spiral threads and smaller intercalaries. The type is about 33 mm. in height and 20 mm. in width. The species L. ovoides (Middendorff) 1848, occurs in the Okhotsk Sea and in the Pleistocene of Yesso, Hokkaido, Japan. Liomesus sulculatus Dall Ldomesus sidculatus Dall, U. S. Geol. Surv., Prof. Paper 59, p. 44, pi. 5, figs. 2, 3, April 2, 1909; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 238, 1916; Howe, Vol. 14, table opposite p. 93, 1922. ? "Monoceros engonatum Conrad," Reagan, Trans. Kansas Acad. Sci., \o\. 22, p. 220, pi. 6, fig. 55, November 24, 1909, not of Conrad, ^'rfe DaU, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 313, 1922. Liomesus "sulcalus" Dall, Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 32, 1916. Shell with about fifteen uniform, flat-topped spiral ridges having equal or wider, not channeled interspaces, the whole surface marked with very fine microscopic spiral striation. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 667 Type specimen: In the IT. S. National Museum, No. 153,904. Type locality: Coos Bay, Oregon; Empire formation, upper Miocene. Miocene: Empire formation of Coos Bay, Oregon (Dall, 1909) ; Montesano formation of western Washington, upper Miocene (Weaver); mouth of Maxfield Creek, Quillayute, Washington, as "Pliocene" (Reagan). Pliocene: Coos conglomerate of Coos Bay, Oregon (Howe); lower part of the Wildcat formation, northern California (Martin). Nomland (Univ. Calif. Publ. Geol., Vol. 10, p. 301, 1917) reported an unidentifiable species of Liomesus in the Santa Margarita formation north of Coalinga. Family BUCCINIDAE Genus BUCCINUM Linnaeus, 1758 Buccinum LinniBUS, Syst. Nat., Ed. 10, p. 734, 1758, includes B. undalum L.; Montfort, Conch. Syst., Vol. 2, pp. 462- 464 and figure, 1810, type B. undalum; Children, Quart. Jour. Sci., Lit., and the .\rts. Vol. 16, p. 59, pi. 5, fig. 195, October, 1823, type Buccinum undalum Linn.; Tryon, Man. Conch., Ser. 1, Vol. 3, p. 100, 1881; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 144, 1901. Type (by subsequent designation, Montfort, 1810), Buccinum undalum Linnseus, figured by Reeve, Conch. Icon., Vol. 3, Buccinum, pi. 1, fig. 3, 1846; north Atlantic. Shell ovate or oblong, covered with a horny epidermis; spire elevated, apex acute; aperture large, oval, emargLnate in front; canal wide, very short, or a mere obhque truncation of the base of the aperture; columella smooth; inner lip expanded; outer lip usually tlun, smooth mtemally; oper- culum ovate, nucleus small near the outer front edge. (Tryon.) The present authors have made no attempt to work out the synonymy of this genus nor of any of the species. There are too many specific names, but lack of some of the literature bearing on this group and an insufficient series of specimens make it imprac- ticable to attempt to change the present status, unsatisfactory as it is. The family Neptuneidce is distinguished principally by its differently formed oper- culum. Liomesus, for instance, would otherwise be assigned to the Buccinidce. It is questionable whether opercula are reliable for separating families. Buccmum glaciale Linnseus Buccinum glaciale Linnaeus, Fauna Suecica, Ed. 2, p. 523, 1761; Syst. Nat., Ed. 12, p. 1204, 1767; Reeve, Conch. Icon., Vol. 3, Buccinum, pi. 3, fig. 18, 1846; Tryon, Man. Conch., Ser. 1, Vol. 3, p. 185, pi. 76, fig. 345, 1881; DaU, U. S. Nat. Mus., BuU. 112, p. 98, 1921; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 238, 1927. Buccinum glaciak "Dall," Meek, Univ. Calif. Publ. Geol., Vol. 14, p. 415, 1923. Shell subulately ovate, sutures of the spire deep, whorls somewhat flattened, longitudmally obliquely phcated, transversely two or three keeled, interstices between the keels regularly, elevately striated; aperture short, lip conspicuously effused; dull yellowish brown, Up white. Size about 60 mm. in length and 35 mm. in width. (After Reeve.) Type specimen: In the collection of the Linnsean Society of London. Type locality: Northern Sea, ^de Oldroyd. Pleistocene: Peard Bay, Alaska (Meek). Recent: Arctic Ocean to Fuca Strait; circumboreal (Dall, 1921). This species has a number of synonyms that have not been included above. The genus is in need of a critical review, which would result in eHminating many useless names. 668 San Diego Society of Natural History [Memoirs Buccinum glaciale Linngeus variety parallelum Ball Tritonium carinntum Dunker, Novit. Conch. Moll. Marina, p. 1, pi. 2, figs. 3, 4, 1858; not Buccinum carinalum Gmelin, 1792, nor of Turton, 1819. Buccinum avgidosum Morch, in Dunker, Novit. Conch. Moll. Marina, ])1. 2, figs. 3, 4, explanation on plate, fide Dall, 1918; not B. angvlosum Gray, 1839. Buccinum glaciale var. parallehim Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 231, 1918; Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919; U. S. Nat. Mus., Bull. 112, p. 98, pi. 8, fig. 10, 1921; I. S. Oklroyd, Stanford Univ. Publ. Geol.i Vol. 2, Ft. 1, p. 239, 1927. Type specimen: In the U. S. National Museum. Type locality: Bering Sea. Pliocene: "Late Pliocene" of St. George Island, Pribilof Islands (Dall, 1919). Recent: Pribilof and Aleutian islands to Cook's Inlet; also Kurile Islands. This variety is so close to the typical variety that it hardly desel-ves separate recognition. Buccinum tenue Gray Buccinum tenue Gray, Zool. Beechey's Voyage, p. 128, pi. 36, fig. 19, 1839; DaO, Exped. to Point Barrow, p. 179, 1885; Journ. Wash. Acad. Sei., Vol. 9, p. 2, 1919; Canadian Arctic Exped., Vol. 8, Pt. A, p. 26A, 1919; U. S. Nat. Mus., Bull. 112, p. 98, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 240, 1927. Type locality: Icy Cape, Arctic, ^de Oldroyd. Pliocene: "Late Pliocene" of St. George Island, Pribilof group (Dall, 1919). Pleistocene: South side of Herschel Island, Yukon Territory, "fragment" (Dall, 1919, p. 26A). Recent: Arctic Ocean southward to Kamchatka to the west, the Aleutian Islands to the east, and thence to Fuca Strait; circumboreal (DaU, 1921). Buccinum polare Gray Buccinum polare Gray, Zool. Beechey's Voy., p. 128, 1839; Dall, U. S. Nat. Mus., Bull. 112, p. 99, 1921; I. S. Old- royd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 243, 1927. Buccinum polare "Dall," Meek, Univ. Calif. Publ. Geol., Vol. 14, p. 415, 1923. Type locality: Icy Cape, Arctic ;^de Oldroyd. Pleistocene: Peard Bay, Alaska (Meek). Recent: Arctic Ocean and south in Bering Sea to Avacha Bay, Kamchatka, on the west, and to Alaska Peninsula on the east (Dall). Buccinum plectrum Stimpson Buccinum plectrum Stimpson, Canadian Naturalist and Geologist, Ser. 2, Vol. 2, p. 374, 1865; Kobelt, Conch. Cab., Ed. 2, pi. 91, fig. 2, 1883; Newcombe, Nautilus, Vol. 10, p. 17, 1896; Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896; Proc. U. S. Nat. Mus., Vol. 24, p. 519, pi. 37, fig. 5, 1902; U. S. Nat. Mus., Bull. 112, p. 98, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 239, pi. 5, fig. 5, 1927. Miocene: "Miocene" of St. Paul Island; Unalaska; Unga Island (Dall, 1896). Recent: Point Barrow, Arctic Ocean, south to Puget Sound; circumboreal (Dall, 1921). This is a handsome species with spiral striations and wavy, generally protractive, axial folds. Buccinum angulosum Gray variety normale Dall Buccimim normale Dall, Rept. Exped. to Pt. Barrow, p. 179, pi. 3, fig. 1, 1885; U. S. Nat. Mus., Bull. 112, p. 100, 1921; Meek, Univ. Calif. Publ. Geol., Vol. 14, p. 415, 1923. Buccinum angulosum normale DaU, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 255, pi. 5, fig. 6, 1927. Type specimen: In the U. S. National Museum, No. 40,966-7. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 669 Type locality: Cape Smythe. Pleistocene: Peard Bay, .\laska (Meek). Recent: Arctic Ocean from Point Barrow to Kotzebue Sound (Dall, 1921). The normal variety lacks the carina of the typical variety.' Buccinum strigillatum Dall Bucdnum strigillatum Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 186, 1891; Vol. 17, p. 706, pi. 17, fig. 9, 1894; U. S. Nat. Mus., Bull. 112, p. 100, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 253, pi. 15, fig. 7, 1927. Buccinum saundersi Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 183, pi. 21, fig. 5, 1914. Type specimens: Of strigillatum, in the U. S. National Museum; of saundersi, in the collection at the University of California. Type localities: Of strigillatum, off Guadalupe Island, Lower California, Mexico, in 167 fathoms; of saundersi, in the upper portion of the Wildcat series two miles south of Centerville, Humboldt County, California, upper Pliocene. Pliocene: At the type locality of saundersi. Recent: Fuca Strait, in 178 fathoms, to San Diego, in 822 fathoms, and to Guadalupe Island, Lower Cali- fornia, Mexico (Dall, 1921). Buccinum tenebrosum Hancock Buccinum. tenebrosum Hancock, Ann. Mag. Nat. Hist., Vol. 18, p. 327, 1846; Dall, U. S. Nat. Mus., Bull. 112, p. 101, 1921, as questionable variety; I. S. Oldroyd, Stanford Univ. Publ. Geol, Vol. 2, Pt. 1, p. 259, 1927. Buccinum f bogachielii Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 218, pi. 5, figs. 51a-6, Nov. 24, 1909; Dall, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 312, 1922. Type specimens: Of tenebrosum, location unknown to the writers; of bogachielii, in the U. S. National Museum. Type localities: Of tenebrosum, west coast of Davis Strait; of bogachielii, Quillayute formation of Washington, upper Miocene. Miocene: Quillayute formation, near Quillayute River, Washington (Reagan). Recent: Bering Strait; circumboreal. Dall (1922) suggested that Reagan's species is probably conspecific with B. tene- brosum. According to Arnold and Hannibal,^ the fossils Reagan reported as Pliocene from the Quillayute formation are redeposited Empire formation species and therefore are Miocene in age instead of Pliocene. Buccinum jordani Hertlein Buccinum jordani Hertlein, Bull. So. Calif. Acad. Sci., Vol. 24, pt. 2, p. 41, pi. 3, fig. 3, 1925. Type specimen: In the type collection at Stanford University. Type locality: Eight miles up Sylvia Creek, Montesano, Washington. Miocene: At the type locality (Hertlein). This form lacks axial sculpture, but has spiral sculpture consisting of fine revolving straps. It has somewhat the shape of B. polare Gray, but the sutures are less depressed. 1 Buccinum angulosum Gray, Zool. Beechey's Voy.. p. 127, pi. 36, fig. 6, 1839: also figxired by Oldroyd. op. cii., pi. 5, figs. 1, 2. 3, pi. 17, figs. 9, 10, 1927. Buccinum gtaciale parallehtm Dall and Buccinum bxri Middendorff variety morchiaiium Fischer (Journ. de Conchyl., Vol. 7, p. 299, pi. 10. fig. 2, 1858, figures reproduced by Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, pi. 27, figs. 1. 2, not figs. 3, 4, 1927) appear more like angulosum Gray, as figured by Oldroyd. than does Dall's variety. ' Proc. Amer. Philos. Soc., Vol. 52, p. 604, 1913. 670 San Diego Society of Natural History [ Memoirs Family NASSARIIDAE Genus NASSARIUS Dumeril, 1805 Arcularia Martini, Neues Syst. Conch. Cab., Vol. 2, p. 18, 1771. Nassarius Dumeril, Zool. Analytique, p. 166, 1806, genus without species; Froriep's translation, p. 167, 1806, only species added, Buccinum arcularia, fide Iredale, Proc. Malac. See. London, Vol. 12, pp. SO, 81, 82, 1916. Arcularia Link, Beschr. Nat. Samml. Univ. Ro.stock, p. 126, 1807. ? Eione Risso, Hist. Nat. Eur. M&id., Vol. 4, p. 171, 1820; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 414, Apr. 18, 1847. "Nassa Martini," H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 116, 18.53. Type (by monotypy), Buccinum arcularia Linnaeus, Syst. Nat., Ed. 10, p. 737, 1758; figured by Reeve, Conch. Icon., Vol. 8, Nassa, pi. 4, figs. 25a, 256, 1853, Philippine Islands; Recent. Shell rather ovate, spire produced; sculpture variable; aperture ovate; anterior canal abruptly truncated and deeply notched; a basal constriction on the exterior of the body whorl usually prominent. Arcularia was used by Martini as a section of Galeodes or Semicassis, which, accord- ing to Martini, is a subgenus of Cassis. In his list of species (pages 89 to 94), he included Arcularia major Martini, stated to be equivalent to Buccinum arcularia Linnseus, which thus becomes the type by absolute tautonomy. However, Martini's work is not con- sistently binomial and is generally disregarded for nomenclatorial purposes. As stated by Woodiing, there is no direct proof that Nassarius Dumeril was proposed as a substitute for Nassa Lamarck. Froriep assigned the single species Buccinum arcu- laria Linnaeus to Nassarius, which thus becomes the type of the genus by monotypy. Eione Risso has for type "Nassa" gibbosula (Linnaeus), which is a gibbous species with very short spire, no sculpture, and an enormous parietal callus. The entire family is in need of a critical review and taxonomic revision. Subgenus NASSARIUS, s. s. Shell with a relatively low but sharp spire ; sculpture essentially of axial ribs with a few faint spiral riblets or striae; outer hp lirate withm and with a posterior notch; anterior canal very deeply notched; iimer lip with a few denticles anteriorly and when a posterior notch is well developed a small^tooth-like plate just anterior to it; body whorl with a large parietal callus definitely delimited; basal constriction on the body whorl present but not deep. Nassarius illustrates the difficulties encountered when a more or less homogeneous group is minutely subdivided. The species with a heavy parietal callus on the body whorl, a short spire, and a posterior notch are certainly different, subgenerically, from the thin-shelled, relatively high-spired species with scarcely a sign of callus on the parietal wall. However, many of the other proposed subdivisions result in unnatural groupings; and in many cases they are not only unnatural but are also difficult to apply. ' In the CaUfornia Miocene there are some species of Nassariidce with a varixed outer lip like Uzita but with sculpture hke that of Alectrion, only finer grained, as might be expected on small species. The type of Alectrion, A. papillosus, shows a sUght tendency to form a varixed lip, and it is quite possible that these Miocene species belong to a minor branch of Alectrion rather than to Uzita, the type of which is a west African shell. However, one species, "Nassa" ocoyana Anderson and Martin, ^ of the CaUfornia Miocene, has the 1 Gabb remarked upon the unnatural arrangement of the speciea of Nassa Lamarck when some of the proposed subdivisional groups are used. (Geol. Surv. Calif., Pateo, Vol. 2, p. 47, 186S-9.) 2 Proc. Calif. Acad. Sci.. Ser. 4, Vol. 4, p. 75, pi. 7, fig. 17, Dec. 30, 1914. Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 671 axial fold-like ribs of the type of Uzita and suggests the use of that group. Until more is known of the relative taxonomic values of characters now used as criteria of subgenera and sections and until the true relationships of the Pacific coast Tertiary species to those of other regions is understood, there is certain to be some nomenclatorial disagreement among conchologists. The arrangement adopted below must be considered purely ten- tative. Nassarius (Nassarius) tegula (Reeve) Plate 26, Figure 43 Nassa tegula Reeve, Conch. Icon., Vol. 8, Nassa, pi. 15, fig. 98, December, 1853; Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 662, 1864; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 74, 1868-9; Pease, Amer. Journ. Conch., Vol. 5, p. S3, 1869; Tryon, Man. Conch., Vol. 4, p. 39, pi. 13, figs. 166, 167, 1882; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 253, 1888; Keep, West Coast Shells, p. 37, fig. 17, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 235, 1903. Arcularia tegula Reeve, Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 577, 1917; Nautilus, Vol. 32, p. 23, 1918. Alectrion (Zeuxis) tegula Reeve, Dall, U. S. Nat. Mu.s., Bull. 112, p. 103, 1921; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Alectrion tegula Reeve, E. K Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Alectrion (Schizopyga) tegulus Reeve, Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 267, pi. 26, fig. 10, 1927. Type locality: Habitat unknown (Reeve); California or Lower California, fide Oldroyd. Pleistocene: Santa Barbara to San Diego (Cooper); lower San Pedro series at Deadman Island and San Pedro, "occasionally found" (Arnold); "Saugus" formation near Ventura (Waterfall); upper San Pedro series at San Pedro, Los Cerritos, Long Beach, Deadman Island, and Crawfish George's, "rare"; also foot of Twenty-sixth Street and at Spanish Bight, San Diego (Arnold); lower Quat- ernary at Magdalena Bay (Dall, 1918; Jordan, 1924); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: San Francisco, California, to Lower California, Mexico. This is a medium-sized, thick-shelled species with a large callus deposit on the parietal wall of the body whorl. The outer lip is somewhat thickened externally. It is sculptured with low axial folds, which are slightly nodose at the shoulder. The outer lip lacks the deep posterior notch of the type species of Nassarius, but the tendency to produce this notch is indicated in some specimens by an incipient groove. Southern specimens of N. tegula have heavier axial sculpture and probably grade into N. luteos- toma (Broderip and Sowerby), of the Panama region. The smaller form inhabiting the Gulf of California has been called Arcularia tiarula Kiener.' Nassarius (Nassarius) complanatus (Powys) Nassa complanata W. L. Powys, Proc. Zool. Soc. London, Pt. 3, p. 96, September, 1835; Reeve, Conch. Icon., Vol. 8, Nassa, pi. 17, figs. Ilia, 1116, 1853. f Buccinum gemma Philippi, Abbild. Beschr. Conch., Vol. 3, Heft 5, p. 44, pi. 1, fig. 5, 1849. Nassa (Zeuxis) complanata Powis, Tryon, Man. Conch., Ser. 1, Vol. 4, p. 33, pi. 10, figs. 105, ? 107, 1882. Alectrion (Hima) complanatus Powys, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 214, 1909. Arcularia complanata Powys, DaD, Proc. U. S. Nat. Mus., Vol. 51, p. 577, 1917; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Gulf of Panama south to S. latitude 25° (DaU, 1909). ? Mexican coast. 1 Buccinum tiarula Kiener, Sp^c. G6n. Icon. Coq. Viv.. Vol. 9, "Buecin." p. Ill, pi. 30. fig. 4, 1841, "Habite la mer des Indes sur les cotes de Madagascar," which may be an error. 672 San Diego Society of Natural History [Memoirs Nassarius complanatus (Powys) is a rather small species, with the whorls of the spire sculptured by small nodosities and the body whorl nearly smooth except for occasional axial ribs near or under the parietal callus. The outer lip is varicose and has about three denticles within. The posterior notch is represented by a vertical groove in the somewhat ascending callus. Subgenus SCHIZOPYGA Conrad, 1856 Nassa Martini, 1771, name used in a binary but not in a binomial s^nse. Nassa Lamarck, 1799, not of Bolten, 1798. Schizopyga Conrad, Proc. Acad. Nat. Sci. Phila. for 1856, p. 315, December, 1856; U. S. Pacific Railroad Reports, Vol. 6, Pt. 2, p. 69, 1857. Type (by monotypy), Schizopyga californiana Conrad. Shell rather thin, bucciniform, with a conspicuous constriction on the base of the body whorl ; sculpture cancellate or with spiral threads and broad axial folds; outer lip simple, Urate within, the posterior notch not developed; parietal wall concave, with or without a callus wash. It is probable that some older name could be used here, such as Tritia Risso;' but the type of that subgenus is not exactly the same. It differs in not having such a deep basal constriction, such a concave inner lip, nor such an abruptly truncated anterior extremity. The sculpture also differs in details. Schizopyga, though of later date, is used here for the sake of conservatism. When the nomenclatorial status of Martini's name is determined, it may have to be used. Alectrion Montfort has been used for the species listed below, but the type of Mont- fort's genus, Buccinum papillosum Linnaeus, has a large, heavy shell, a prominent pos- terior notch on the rather thick outer lip, and a broadly concave columella with a rather narrow but heavy callus deposit projecting anteriorly into a pointed extremity. It is very different from the California shells of the perpinguis clan. Nassarius (Schizopyga) calif omianus (Conrad) Plate 26, Figure 49 Schizopyga californiana Conrad, Proc. Acad. Nat. Sci. Phila. for 1856, p. 315, December, 1856; U. S. Pacific Railroad Repts., Vol. 6, Pt. 2, p. 69, pi. 2, fig. 1, 1857; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 593, 1864. "Nassa fossala Gould," Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 74, in part only, 1868-9. Nassa californiana Conrad, Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 177, 1891; Arnold, Proc. U. S. Nat. Mus., Vol. 34, pi. 36, fig. 6, 1908; ? U. S. Geol. Sunr., Bull. 396, pi. 27, fig. 8, 1910; ? Bull. 398, pi. 49, same figure, 1910; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 221, 1917; probably not, or only in part, of Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 231, not pi. 4, fig. 3, 1903. Alectrion (Schizopyga) californiana Conrad, DaU, U. S. Nat. Mus., BuU. 112, p. 102, pi. 11, fig. 4, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 264, pi. 26, fig. 13, 1927, reproduction of Dall's figure. Alectrion californiana Conrad, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Type locality: Santa Clara, California (Santa Clara County); presumed to be Miocene. Miocene: Santa Clara (Conrad). Pliocene: Purisima and Merced formations of the San Francisco region; common in the Jacalitos and Etche- goin formations, but lacking in the "Mya japonica zone," Coalinga district (Nomland); etc.; etc. Pleistocene: San Pedro region; lower Quaternary of Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926). Recent: Oregon to San Ignacio Lagoon, Lower California, Mexico (Dall, 1921). ■ Hist. Nat. Eur. M^rid., Vol. 4, p. 172, footnote, 1826, list includes "Planaxia reticulata" Linnaeus. Type designated by Gray, Proc. Zool. Soc. London for 1847, p. 139, 1847. Volume I ] PlIOCENE AND PLEISTOCENE MOLLXJSCA OF CALIFORNIA 673 Because of the confusion of this species with iV. perpinguis, fossatus, and possibly others, the occurrences given in the Hterature cannot be depended upon. N. calif ornianus, as figured by Conrad, appears to be finely papillose, in a rectilinear pattern. The figures given by Arnold (1910) are of a peculiar young form and cannot be considered typical. N. californianus appears to be closely related to perpinguis, but whether the shell figured by Dall (1921) as californianus is identical with Conrad's presumed Miocene species cannot be said at the present time. Arnold's figure in his San Pedro memoir (1903) is not typical of Conrad's species, and may be of an undescribed variety or even a new species. Nassarius (Schizopyga) californianus (Conrad) variety coaUngensis (Arnold) Nassa californiana Conrad, var. coaUngensis Arnold, U. S. Geol. Siirv., Bull. 396, p. 88, pi. 27, fig. 9, January 15, 1910; Bull. 398, pi. 49, same figure, 1910. Type specimen: In the U. S. National Museum, No. 165,511. Type locality: Henry Spring, four miles south of Coalinga; Pliocene. Pliocene: Several localities in the Etchegoin formation of the Coalinga region (Arnold). The variety coaUngensis is somewhat like A^. perpinguis, but is more elongate, the whorls of the spire are less ventricose, though slightly tabulated near the suture, and the body whorl is slightly constricted just below the suture. It has much finer sculpture than typical N. californianus, particularly as figured by Ai-nold (1910). Nassarius (Schizopyga) perpinguis (Hinds) Plate 26, Figures 51, 52 Nassa perpinguis Hinds, Zool. Voy. Sulphur, MoUusca, p. 36, pi. 9, figs. 12, 13, 1844; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 662, 1864; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 75, 1868-9; Tryon, Man. Conch., Ser. 1, Vol. 4, p. 56, pi. 17, fig. 319, 1882; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 253, 1888; Keep, West Coast Shells, p. 37, fig. 18, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 234, 1903. Nassa intaslriala Conrad, U. S. House of Representatives, House Document No. 129, p. 17, July, 1855, reprinted by Dall, U. S. Geol. Surv., Prof. Paper 59, p. 169, 1909. Nassa inlerstriala Conrad, U. S. Pacific Railroad Surveys, Vol. 5, p. 327, 1856, correction in spelling of "intastriata." Nassa perpinguis, var. bifasdala Berry, Nautilus, Vol. 22, p. 39, 1908. Alectrion perpingvis Hinds, Dall, U. S. Nat. Mus., Vol. 51, p. 576, 1917; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 250, 251, 1929. Alectrion {Schizopyga) perpinguis Hinds, Dall, U. S. Nat. Mus., Bull. 112, p. 103, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 12, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 266, pi. 26, fig. 11, 1927; WaterfaU, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type specimen: In the Zoological Museum, Copenhagen, jide I. S. Oldroyd. Type localities: Of perpinguis, Magdalena Bay, Lower California, Mexico, Recent; of intastriata Conrad, Santa Barbara, Pleistocene; of variety hifasciata, San Pedro, Recent. ? Miocene: Santa Monica and Miso Creek, Los Angeles Coimty (Cooper). Pliocene: San Diego well (Dall); "Pico" near Ventura (Waterfall). Pleistocene: "Pliocene" of Deadman Island and Timms Point; rare in the lower San Pedro series of San Pedro (Arnold, 1903); plentiful in the lower San Pedro of Nob Hill cut, San Pedro (T. S. Old- royd); irrigation ditch near Ventura (Arnold, 1903); "Saugus" near Ventura (WaterfaU); Santa Barbara (Conrad); S. D. S. N. H. locality 74, southwest of Goleta, Santa Barbara County (U. S. G.); at the Chiton bed at Point Firmin (Chace); Spanish Bight and Pacific Beach (Arnold) and near Mexican boundary monument No. 258, San Diego County (Stephens) ; lower Quaternary at Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926); Santa Monica (F. C. Clark); etc. Recent: Puget Sound to Magdalena Bay, Lower California, Mexico. 674 San Diego Society or Natural History [ Memoirs This is the common, evenly ventricose, reticulated species. There is a narrow but distinct shelf just at the suture on most specimens. Berry's variety bifasciatus is a color form due to weathering and is of no consequence. Collections of shells of this species (as well as of some other species in this genus) show a tall and a short form which may be due to sexual dimorphism. N. perpinguis has much finer cancellate sculpture than N. calif ornianus (Conrad). Nassarius (Schizopyga) mendicus (Gould) Plate 26, Figure 54 Nassa mendica Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 155, 1851; U. S. Expl. Exped. (WOkes'), Vol. 12, p. 262, Atlas, pi. 19, fig. 331, 1852; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 662, 1864; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 74, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 253, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 233, 1903; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 422, 1915; Howe, Univ. Calif. Publ. Geol., Vol. 14, table opp. p. 93, 1922. Nassa woodwardi Forbes, Proc. Zool. Soc. London for 1850, p. 273, pi. II, fig. 3, 1850. Nassa gibbsii W. Cooper, U. S. Pacific Railroad Repts., Supplement to Vol. 1, Part 3, p. 371, 1859. Aleclrion mcndims Gould, Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 576, 1917; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art,. 22, p. 11, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Schizopyga mendica Gould, Dall, U. S. Nat. Mus., BuU. 112, p. 102, 1921. Aleclricm coo-peri, var. woodwardi Forbes, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 12, 1925. Aleclrion (Schizopyga) mendicus Gould, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 265, pi. 26, figs. 6, 14, 1927. Aleclricm mendicus indispulahilis I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, pi. 26, fig. 4, 1927. Aleclrion (Schizopyga) mendica Gould, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type specimen: In the collection of the Boston Society of Natural History. Type localities: Of mendica, Nisqually, Port Discovery, Puget Sound; of gibbsii, Port Townsend, Puget Sound; both Recent. Miocene: Empire formation of Coos Bay, Oregon (Howe); Kirker's Pass, Contra Costa County (Cooper); lower San Pablo formation of middle California (Clark). Pliocene: Twelve Mile House, San Mateo County; Pico near Ventura (Waterfall); San Diego well, San Diego (Cooper); Etchegoin formation of California (Clark); Bath-house Beach, Santa Barbara (Arnold). Pleistocene: At all the fossUiferous localities in the vicinity of San Pedro (Arnold); lower San Pedro fauna of Nob Hill cut at San Pedro (T. S. Oldroyd) ; Barlow's Ranch and old irrigation ditch at Ventura, also at Spanish Bight and Pacific Beach, San Diego (Arnold); late Pleistocene southwest of Goleta, loc. 74 (U. S. G.); palisades of Santa Monica (in Oldroyd Collection at Stanford University); chiton bed at Point Firmin, Los Angeles County (Chace); "Saugus" near Ventura (Waterfall); lower Quaternary at Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926); etc. Recent: Kodiak Island, Alaska, south to Magdalena Bay, Lower California, Mexico (Dall, 1921). Nassarius mendicus (Gould) has a narrow spire, with fine spiral sculpture and axial plications. It grades into variety cooperi, a variety with few, broad undulous axial ribs. N. mendicus differs from perpinguis in its fewer, more continuous axial ribs. The form figured as indisputabilis is of no consequence. Nassarius (Schizopyga) mendicus (Gould) variety cooperi (Forbes) Plate 26, Figures 40, 50 Nassa cooperi Forbes, Proc. Zool. Soc. London for 1850, p. 273, pi. 11, fig. 4, 18.50; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 662, 1864; Gabb, Geol. Surv. Calif., Palajo., Vol. 2, p. 74, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 253, 1888; Keep, West Coast SheUs, p. 37, fig. 18, 1888, 1892. Nassa (Trilia) mendica Gould, var. cooperi Forbes, Tryon, Man. Conch., Ser. 1, Vol. 4, p. 56, pi. 17, figs. 322, 323, 1882. Nassa mendica Gould, var. cooperi Forbes, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 234, 1903. Nassa mendica cooperi Forbes, Berry, Nautilus, Vol. 22, p. 38, 1908. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 675 Aleclrion cooperi Forbes, Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 576, 1917; T. S. Oldroyd, Proe. U. S. Nat. Mus.> Vol. 65, Art. 22, p. 12, 1925; E. K. Jordan, Proc. Calif. Acad. Sei., Ser. 4, Vol. 15, p. 245, 1926. Aleclrion mendica Gould, var. cooperi Forbes, E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919. Schizopyga cooperi Forbes, Dall, U. S. Nat. Mils., Bull. 112, p. 102, 1921. Aleclrion (SchizOpyga) coopen Forbes, Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 265, pi. 26, fig. 8, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type locality: Said to be Sandwich Islands, possibly a ballast shell. ? Miocene: Kirker's Pass, Contra Costa County (Cooper). Pliocene: Twelve Mile House, San Mateo County; San Diego well, San Diego (Cooper); Bath-house Beach, Santa Barbara (Berry). Pleistocene: "Saugus" near Ventura (Waterfall); "Pliocene" and lower and upper San Pedro series of San Pedro (Arnold); southwest of Goleta, loc. 74 (U. S. G.); at the Chiton bed on Point Firmin (Chace); Santa Monica (collection of F. C. Clark); Pacific Beach, San Diego (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Puget Sound to San Diego, California (Dall, 1921). This variety has fewer but larger axial ribs than the typical mendicus. In Tremper's collection there are specimens which show perfect intergradation between typical men- dicus and the form cooperi. There are two forms, a tall and a short, which may represent the different sexes. Nassarius (Schizopyga) cerritensis (Arnold) Nassa cerritensis Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 231, pi. 4, fig. 1, 1903. Alectnon cerritensis Arnold, Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 576, 1917; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Schizopyga cerritensis Arnold, Dall, U. S. Nat. Mus., Bull. 112, p. 102, 1921. Aleclrion (Schizopyga) cerritensis Arnold, L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 266, 1927. Type specimen: In the U. S. National Museum, No. 162,553. Type locality: Los Cerritos (Signal Hill), Los Angeles County;' Pleistocene. Pleistocene: Los Cerritos, "rather common"; "one or two specimens" from the upper San Pedro series at San Pedro, Long Beach, and Crawfish George's, Los Angeles County; also Spanish Bight, San Diego (Arnold); lower Quaternary at Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926). Recent: Long Beach, California, to Magdalena Bay, Lower California, Mexico (Dall, 1921). This species is more elongate than fossatus and has fewer axial ribs. Nassarius (Schizopyga) fossatus (Gould) Plate 26, Figures 55, 56 Buccinum elegans Reeve, Proc. Zool. Soc. London, Pt. 10, p. 199, Feb., 1843, not Bucdnum elegans Brown, 1841, nor of Dujardin, 1837, nor of Kiener, 1834, nor of Risso, 1826, nor of Sowerby, 1824, nor of Costa, 1822. Buccinum fossatum Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 152, 1849. Nassa reevei A. Adams, Proc. Zool. Soc. London for 1851, p. 109, new name for Buccinum elegans Reeve. Nassa fossata Gould, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 74, 1868-9; Cooper, 7th Ann. R«pt. Calif. State Min- eralogist, p. 253, 1888; Keep, West Coast Shells, p. 36, fig. 16, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 232, 1903. Nassa (Tritia) fossata Gould, Tryon, Man. Conch., Ser. 1, Vol. 4, p. 55, pi. 17, figs. 316, 317, 1882. Aleclrion fossatus Gould, Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 575, 1917; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art-. 22, p. 11, 1925; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 250, 252, 254, 1929. Aleclrion fossata Gould, E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; E. K. Jordan, BuU. So. Calif. .\cad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Schizopyga fossata Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 102, 1921. Aleclrion (Schizopyga) fossatns Gould, L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 264, pi. 26, figs. 1, 3, 5, 7, 9, 1927. Aleclrion (Schizopyga) fossata Gould, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. ' In the original reference, Arnold states that the type came from Los Cerritos. In U. S. Nat. Mus., Bull. 53, p. 426, the holotype is stated to have come from Spanish Bight, San Diego, at which place the new species was also stated by Arnold to occur. 676 San Diego Society of Natural History [Memoirs Type locality: "Puget Sound and Mouth of Columbia River" (Gould). Miocene: "Martinez, Walnut Creek, Contra Costa County; Griswold's, San Benito County; Foxin's, Santa Barbara County" (Cooper). Pliocene: "Danger Creek, Humboldt County; Russian River, Santa Rosa, Sonoma County; Twelve-mile House, and Seven Mile Beach, San Mateo County; west of San Jose, Santa Clara County; Soquel, Santa Cniz County; San Diego well" (Cooper); "Pico" of Ventura district (Waterfall). Pleistocene: "Pliocene" at Deadman Island, and lower San Pedro series at Deadman Island and San Pedro; old irrigation ditch and Barlow Canyon, Ventura (Arnold) ; Santa Barbara to San Diego (Cooper) ; upper Pleistocene terrace southwest of Goleta, Santa Barbara County (U. S. G.); "Saugus" of Ven- tura district (Waterfall) ; chiton bed at Point Firmin (Chace) and all upper San Pedro localities in the vicinity of San Pedro (Arnold); several upper Pleistocene localities in San Diego region (Arnold; Stephens) ; lower Quaternary at Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower California, Me.xico (Jordan, 1924, 1926); etc. Recent: Vancouver Island, British Columbia, to Cedros Island, Lower California, Mexico (Dall, 1921). This large species varies markedly in the strength of its axial ribs. The next form is probably a variety on which the axial ribs are much weaker. Nassarius (Schizopyga) moranianus (Martin) Nassa moraniana Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 183, pi. 22, figs, la, lb, Ic, August 6, 1914. Alectrion grammalus Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 575, 1917. Alectrion nwraniamm Martin, Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 49, 1926. Alectrion (Schizopyga) ynoranianus Martin, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Shell large, rather solid, oval, whorls of spire rapidly increasing in size, body whorl large, globose; sculpture consisting of rather uniform spiral riblets, with or without small intercalary threads, and axial riblets over which the spirals tend to produce small nodes. Type specimens: Of moranianus, in the collection at the University of California; of gram,matus, in the U. S. National Museum, No. 101,721. Type localities: Of moranianus, Merced formation of Bolinas Bay, California, Plio- cene; of grammatus, "Pleistocene of Santa Barbara" (Dall). Pliocefie: Fugler's Point, Santa Barbara Coimty (Carson); "common in the Pliocene formations of the cen- tral coast region of California" (Martin). Pleistocene: Santa Barbara (Dall, as grammatus). Recent: In collections as gouldii. This species is like fossatus but is shorter and the axial ribs on the body whorl are finer and not emphasized on the upper portion of the whorl. Alectrion grammatus Dall appears to be a synonym and its type locality may be the Pliocene of Santa Barbara instead of Pleistocene as given by Dall. Nassarius (Schizopyga) waldorfensis (Arnold) Nossa waldorfensis Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 16, pi. 54, fig. 17, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914. Type specimen: In the U. S. National Museum, No. 165,272. Type locality: Waldorf asphalt mine, three miles southeast of Guadalupe, Santa Barbara County, California; Pliocene. Pliocene: At the type locality; Elsmere, Holser, and Pico canyons, Los Angeles County (English); "found abundantly in the Pliocene throughout southern California" (Arnold, op. dt.). According to Arnold, this species "is slenderer and has coarser axial sculpture than A'^. perpinguis Hinds, and is somewhat smaller, relatively broader, and has much sharper ribs than N. mendica Gould; it is more closely related to the latter than to any other of the West Coast species." VoLOTfE I ] Pliocene and Pleistocene Mollusca of California 677 Nassarius insculptus (Carpenter) Nassa insculpta Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 662, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 223, 1866; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 212, pi. 23, fig. 6, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 233, 1903. Nassa (Zeiixis) inscvlpta Carpenter, Tryon, Man. Conch., Ser. 1, Vol. 4, p. 38, pi. 12, fig. 154, 1882. Aleclrimi insailptvs Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 576, 1917. Alectrion insculptus, variety eupleura DaU, Proc. U. S. Nat. Mus., Vol. 51, p. 576, January 15, 1917. Zeuxis insculptus Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 103, 1921. Zeuxis insculptus eupleura DaU, U. S. Nat. Mus., Bull. 112, p. 103, 1921. Alectrion (Schizopyga) insculptus Carpenter, I. S. Oldroyd, Stanford Univ. Ppbl. Geol., Vol. 2, Pt. 1, p. 267, pi. 26, fig. 12, 1927. Alectrion (Schizopyga) insculptus eupleura Dall, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 267, 1927. Type s-pecimens: Of insculptus, in the State collection, University of California, fide Oldroyd; of eupleura, in the U. S. National Museum, No. 209,046. Type localities: Of insculptus, Catalina Island, California, Recent; of eupleura, not stated by Dall, but somewhere between San Simeon, California, and Cedros Island, Lower California, Mexico. Pliocene: Lower part of the upper Pliocene at Fifth and Hope Streets, Los Angeles, California. Pleistocene: Upper San Pedro series at San Pedro, "One specimen" (Arnold). Recent: Point Arena, California, to Cedros Island, Lower California. Nassarius insculptus (Carpenter) is well figured by Tryon, Williamson and Oldroyd. It is characterized by fine spiral sculpture and by the absence of axial sculpture, except on the small, upper whorls of the spire. The inner lip has a definitely delimited parietal callus. The form eupleura is an individual variation of no taxonomic value. Nassarius versicolor (C. B. Adams) Nassa versicolor C. B. Adams, Ann. Lyceum Nat. Hist., New York, Vol. 5, p. 66 (pagination of the separate), 1852. Nassa versicolor var. striatula C. B. Adams, op. cil., p. 66, 1852. Nassa (Hima) versicolor C. B. Adams, Tryon, Man. Conch., Ser. 1, Vol. 4, p. 50, pi. 15, fig. 270, 1882. Alectrion versicolor C. B. Adams, Dall, Proc. U. S. Nat. Mus., Vol. 51, p. 576, 1917. Shell rather small, with .spiral threads and axial ribs. Type locality: Panama; Recent. Recent: Magdalena Bay, Lower California, Mexico, to Payta, Peru (Dall). Variety versicolor, s. s. Outline of whorls of spire nearly rectilinear, axial ribs very prominent. The typical form was stated to have the spiral striae nearly obsolete on the middle of the whorls. The form covered with very distinct striae Adams named variety striatula. Nassarius versicolor (C. B. Adams) variety hooveri (Arnold) Nassa versicolor C. B. Adams, var. hooveri Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 236, pi. 4, fig. 6, 1903. Shell with a shorter spire and more abruptly trimeated anteriorly; axial ribs rounded, sinuous. Type specimen: In the U. S. National Museum, fide Arnold. Type locality: San Pedro; Pleistocene. Pleistocene: Upper San Pedro series at San Pedro, two specimens (Arnold). 678 San Diego Society of Natural History [Memoirs Subgenus UZITA H. and A. Adams, 1853 VzUa H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 120, 1853; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 205, 1901; Woodring, Carnegie Inst., Publ. No. 385, p. 265, 1928. Type (by subsequent designation, Cossmann, 1901), Buccinum viiga Bruguiere, figured by Reeve, Conch. Icon., Vol. 8, Nassa, pi. 13, fig. 86, 1853, and by Tryon, Man. Conch., Ser. 1, Vol. 4, p. 42, pi. 13, fig. 191, ? figs. 192, 193, 1882; west Africa, Recent. Shell relatively small, stout, abruptly truncated anteriorly, with spiral striae or cords and axial ribs; aperture broadly ovate, tyj^kally with a posterior internal notch or sulcus; outer lip usually varicose, with internal hrations; anterior canal a deep, curved notch; inner lip typically with a sharply delimited callus deposit and some irregular denticles; parietal wall broadly concavely archeci. There is some doubt whether the California Miocene species with varicose outer lips belong to this subgenus. Nassarius arnoldi (Anderson) has a varicose lip, but its even, reticulate sculpture suggests a closer relationship with the Schizopyga clan. Typical Uzita is represented in the Caribbean Miocene by Nassarius (Uzita) cercadensis (Maury) and gurabensis (Maury).' Nassarius (Uzita) hamlini (Arnold) Nassa hamlini Arnold, Proc. U. S. Nat. Miis., Vol. 32, p. 537, pi. 50, fig. 9, 1907; U. S. Geol. Surv., Bull. 309, pi. 40, fig. 9, 1907. Type specimen: In the U. S. National Museum, No. 164,946. Type locality: Third Street tunnel, Los Angeles; Pliocene. Pliocene: Third Street tunnel, Los Angeles (Arnold). No specimen of this species has been examined, and it is possible that the species may not belong to Uzita. According to Arnold's figure and description, it has spiral raised lines, axial ribs, a thickened outer lip, and an incrusted inner lip. Nassarius (Uzita) antiselli (Anderson and Martin) Nassa antiselH Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 76, pi. 7, fig. 16, 1914. Type specimen: At the California Academy of Sciences, No. 165. Type locality: Eastern San Luis Obispo County, Miocene (Anderson and Martin). Miocene: At the type locality. ? Pliocene: Questionably in the middle Etchegoin from a depth of 2886 feet in a well near Tipton, Tulare County (H. R. G.) This species has both axial and spiral ribs and a conspicuously varixed outer lip. It closely resembles typical Uzita. N. lincolnensis (Anderson and Martin) was described as lacking the varix on the outer lip. N. andersoni (Weaver),- from the Chehalis forma- tion of Washington (Miocene), and N. pabloensis (Clark), ^ of the upper Miocene of the Mount Diablo region and Walnut Creek, appear to be closely related to antiselli and should probably be treated as synonyms. 1 See Woodring, Carnegie Inst., Publ. No. 385, p. 266, plate 16, figs. 4 (cercadensis) and 5, 6 (gurabensis), 1928. 2 Washington Geol. Surv., Bull. 15, p. 75, pi. 6, fig. 56, 1912. >Univ. Calif. Publ. Geol., Vol. 8, p. 493, pi. 65, figs. 8, 9, 1915. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 679 Nassarius (Uzita) amoldi (Anderson) Nassa amoldi Anderson, Proc. Calif. Acad. Sci., Ser. 3 (GeoL), Vol. 2, p. 204, pi. 16, figs. 70, 71, December 4, 1905. Type specimen: In the California Academy of Sciences. Type locality: "Lower Miocene beds of Kern River." Miocene: Lower or possibly middle Miocene beds of Kern River (Anderson). This is a small species with reticulate sculpture and a thickened outer lip. Its sculp- ture differs from that of typical Uzita; but if antiselU is a Uzita, this species probably is also, for the two species are connected by intermediate forms. Nassarius (Uzita) amoldi (Anderson) variety whitneyi (Trask) Plate 26, Figures 48a, 48b Nassa whUneiji Trask, Univ. Calif. Publ. Geol., Vol. 13, p. 154, pi. 7, figs. 3, 6, May 10, 1922. Type specimen: In the collection at the University of California, No. 12,387. Type locality: Briones formation of middle California. Miocene: Common throughout the Briones formation, upper Miocene of middle California (Trask). Pliocene: Middle of the Etchegoin formation at a depth of 2680 feet in a well near Tipton, Tulare County (H. R. G.). This variety is larger and has more numerous but less prominent ribs. However, it may not be of significance. The outer lip is varicose, but the superficial resemblance to Nassarius (Schizopyga) californianus (Conrad) is shown on plate 26 (compare figures 48 and 49). Family PYRENIDAE (COLUMBELLIDAE) Shell oval, spire more or less developed; aperture oval to elongate and narrow, usually ending in a short, open anterior canal; outer lip simple, or thickened and denticulate or lirate within; inner lip often with denticles, sometimes one or more lirations; average size small; epidermis present; operculum small, horny. Most of the genera in this family are clearly connected by border-line species. Some species possess some of the characters of two or even tkree genera and their assignment to any one genus becomes a matter of personal opinion. The subgenera and sections are even less definitely isolated from each other ; but there are a number of minor natural groups which deserve separate names, and all that appear to be vaUd and can be applied to the Pacific coast fauna are recognized below. Since the Museum Boltenianum is used for nomenclatorial purposes, the family name must be Pyrenidce instead of the more familiar Columbellidce. Should Bolten's catalogue be ruled out by the International Commission on Zoological Nomenclature, the family name will again become Columbellidce, the subgenus Columhella will take gen- eric rank, and Pyrene will be replaced by Conella as a subgeneric group under Lamarck's genus ColumbeUa. If the genus Columbellaria Rolle, 1861, properly belongs to the Pyrenidce, the family ranges from the Jurassic to the Recent. The greatest development of the family appears to be in the Recent fauna. 680 San Diego Society of Natural History [ Memoirs Genus PARAMETARIA DaU, 1916 "Conella Swainson," H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 185, October, 1853, not of Swainson, 1840. Meta Reeve, Conch. Icon., Vol. 11, Columbella, discussion under Columhella picata, April, 1859; Meta, pi. 1, May, 1859; not Mela Koch, 1835, Arachnids. Parametaria Dall, Nautilus, Vol. 30, p. 25, July, 1916, new name for Meta Reeve, 1859, not Koch, 1835. Type (by subsequent designation, Reeve/ 1859), Conus dwpontii Kiener, figured by Reeve; Gulf of California, Recent. Shell shaped like that of Conus but with denticulations or lirations on the inner side of the outer lip. Distribution: Tropical and subtropical seas. This small genus of coniform Pyrenidce has not been found in the fossil state on the Pacific coast. Specimens might readily be confused with Conus. The genus grades into Pyrene through such species as ovuloides C. B. Adams (? = ovulata Lamarck). Genus MICROCITHARA Fischer, 1884 Microcilhara Fischer, Man. Conchyl., p. 638, June, 1884. Txjpe (by monotypy), C. harpiformis Sowerby, Proc. Zool Soc. London for 1832, p. 113, 1832; figured by Reeve, Conch. Icon., Vol. 11, Columhella, pi. 7, figs. 30a-6, 1858; also figured by Tryon, Man. Conch., Ser. 1, Vol. 5, p. 196, pi. 63, fig. 63, 1883. Distribution: Tropical west American coast. The most noticeable feature of this genus is the protruding posterior portion of the outer lip. Typically, the shell is cone shaped, with a low spire, but M. uncinata (Sowerby)- is rather high spired. M. harpiformis is a Panama shell. Tryon (1883) placed these two species in Columbellina d'Orbigny,' an extinct genus, but they probably do not belong there. M. harpiformis has a very long, narrow aperture, approximately equal to the entire length of the shell. C. monodactylus has a different shape, the aperture is acutely oval, and the inner lip widely overlaps the body whorl. There has been some doubt whether Columbellina belongs to the Pyrenidce. Genus PYRENE Bolten, 1798 Pyrene Bolten, Mus. Boltenianum, p. 134, 1798. Conella Swainson, Treat. Malac, pp. 149, 312, fig. 17a on p. 151, 1840; type (by monotypy) C. picata Swainson (not "picta Swainson" Reeve) = C. ovulata Lamarck (fide Pace), or more likely discors (Gmelin). Pusiosloma Swainson, Treat. Malac, p. 313, 1840; type (here designated) C. fulgurans Lamarck, Hist. Nat. Anim. s. Vert., Vol. 7, p. 296, 1822; figured by Reeve, Conch. Icon., Vol. 11, Columbella, sp. 50, 1858. Conidea Swainson, Treat. Malac, p. 313, 1840; type (by monotypy) Columbella scmiptmctata Lamarck, = C. discors Gmelin. Type (by monotypy), Pyrene rhombiferum Bolten, 1798, = Buccinum punctatum Bruguiere, = Valuta discors Gmelin. Bolten refers to Martini's figures: Conch. Cab., Vol. 2, [p. 134,] pi. 44, fig. 465, [466, 1773]. This .species is figured below, plate 26, figure 42. 1 Cited as type in discussion under Meta macrostoma, May, 1S59. In the April reference referred to above Reeve briefly defines the new genus but ascribes no species to it. 2Proo. Zool. Soc. London for 1832, p. 114, 1S32, figured by Reeve, Conch. Icon., Vol. 11, Columbella. pi. 23, fig. 142, 185S, and by Tryon, Man. Conch.. Ser. 1, Vol. 5, p. 196, pi. 63, fig. 64, 1883. •Palfio. Francaise, Terr. Cret., Vol. 2, p. 346, 1842, type, "C. monodactylus d'Orbigny," a species from the lower Neocomien (Cretaceous), fide Cossmann, Ess. Paldo. Comp., Vol. 4, p. 230, 1901. The original spelling was Colovibellina, but was emended by Rolle, K. Akad. Wissen. Wien, Sitzunsb. Math. — Natur. Classe, Vol. 42. p. 262, 1861. The genus is represented in North America by Columbellina aviericana Wade. U. S. Geol. Surv., Prof. Paper 137, p. 153, pi. 53, figs. 14, 15, 1926, Ripley formation, upper Cretaceous of Tennessee, but the species appears to be sectionally distinct from Columbellina, 8. 3. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 681 Shell large, heavy, elongate-ovate, spire moderate; whorls tightly coUed, sutures channeled or appressed; smooth or spirally sculptured; aperture half to three-quarters length of shell, elongate; outer Up usually thickened in the middle, Hrate or denticulate within and sometimes striate on the exterior side, posterior part sometimes expanded or ascending on the body whorl; inner lip lirate or denticulate, sometimes with a small phcation deeply placed within the aperture; anterior canal short, rather narrow, slightly recurved or notched, causing the columella to appear obliquely trun- cated. Geologic range: Early Tertiary to Recent. Distribution: World wide in tropical and subtropical waters. The type of this genus is a Philippine shell, with which a number of tropical west American shells are congeneric. Subgenus PYRENE, s. s. Exterior of shell smooth, except for low spiral cords around the lower part of the body whorl. Pyrene (Pyrene) fuscata (Sowerby) Cobimbella fuscata Sowerby, Proc. Zool. Soc. London for 1832, p. 117, 1832; Miiller, Synop. Nov. Test. Viv., p. 88, 1836; Sowerby, Thes. Conch., Vol. 1, Cobimbella, p. 114, pi. 36, figs. 21, 25, 1844; Deshayes in Lamarck, Hist. Nat. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 10, p. 276, 1844; C. B. Adams, Ann. Lye. Nat. Hist. N. Y., p. 311, 1852; Reeve, Conch., Icon., Vol. 11, Columbella, sp. 9, pi. 2, figs. 9a-6, 1858; Carpenter, Proc. Zool. Soc. London, p. 344, June, 1863; Rept. Brit. A.ssn. Adv. Sci. for 1863, pp. 539, 625, 665, 1864; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 105, pi. 42, figs. 19-21, 1SS3; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 216, 1909; I. S. Old- royd, Nautilus, Vol. 32, p. 27, 1918; Zetek, Los Moluscos Panama, p. 22, 1918; Orcutt, Nautilus, Vol. 33, p. 67, 1919; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Coluvibella meleagris Duclos, Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 9, Columbelle, p. 10, pi. 3, fig. 3, 1841; d'Orbigny, Voy. Amer. M^rid., MoU., p. 430, 1843. Pyrene fuscata Sowerby, Tomlin, Journ. Conch., Vol. 18, no. 6, p. 161, 1927. Pliocene: Southwest point of Coronado Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Upper Pleistocene of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Gulf of California, Mexico, to Paita, Peru, and the Galapagos Islands, La Jolla and San Diego (Orcutt). This species is much like Pyrene discors (Gmelin) , the type of the genus ; but the body whorl is relatively much larger than the penultimate whorl, and spiral sculpture is en- tirely lacking. The outer lip is thickened in the middle and has numerous small internal lirations. The inner lip has fewer but larger lirations. Recent specimens vary in color, being frequently brown with white maculations. Colmnhella meleagris Duclos, as figured by Kiener, is certainly a synonym. Tryon gives C. nodalina Duclos and C. pallescens Wimmer as additional synonyms. Pyrene (Pyrene) strombiformis (Lamarck) Columbella strombiformis Lamarck, Hist. Nat. Anim. s. Vert., Vol. 10, p. 266, 1822; Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 9, Columbelle, p. 3, pi. 1, figs. 1, la, 1841; d'Orbigny, Voy. Amer. Merid., Moll., p. 429, 1843; Sowerby, Thes. Conch., Vol. 1, Columbella, p. 110, pi. 36, figs. 1, 2, 1844; C. B. Adams, Ann. Lye. Nat. Hist. N. Y., Vol. 5, p. 322, 1852; Carpenter, Reigen CoU. Mazatlan Moll. Brit. Mus., p. 490, 1857; Reeve, Conch. Icon. Vol. 11, Columbella, sp. 8, pi. 2, figs. 8a, 86, 1858; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 104, pi. 42, figs. 5-10, 1883; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 216, 1909; Zetek, Los Molu.scos Panama, p. 49, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pt. 5, pp. 149, 155, 1924. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Cape San Lazaro, Lower California, Mexico, to Paj^ta, Peru. Pyrene strombiformis (Lamarck) belongs to the group of species with the po.sterior part of the outer lip distended, forming a shoulder on the apertural portion of the body whorl. In some species, as paytensis (Le.sson) and castania (Sowerby), a tabulation is thus 682 San Diego Society of Natural History [ Memoirs formed below the suture which continues on the spire whorls up to the apex. P. strom- biformis is very close to P. major (Sowerby)S as pointed out by Carpenter; but the former is supposed to be somewhat rounder in the spire and it has a color pattern developed in streaks instead of spots. The olive-colored epidermis of strombiformis has fine, incised spiral serrations all over, whereas major has them only on the upper part of the shell. Pyrene major is best regarded as a variety of strombiformis; as a fossil it would be indis- tinguishable from the older species. Pyrene. labiosa (Sowerby)- a Recent species of west Colombia, belongs with the group not having a prominent shoulder or tabulation on the whorls and with no spiral sculpture. It has an outer lip much thickened in the middle, causing the aperture to be narrow and sinuous. The lip flares slightly externally because of the unusual thickening. "Colum- bella venilia Duclos" is said to be a synonym. Pyrene payiensis (Lesson), a Recent species ranging from Panama to Peru, has a sloping tabulation below the suture, as previously mentioned. This tabulation is em- phasized in P. castania (Sowerby) , occurring in Central American waters and at the Gala- pagos. Pyrene hoemastoma (Sowerby), of the Pacific coast of Mexico, Gulf of California, and the Galapagos, belongs to the strombiformis group, but has distinctive coloration. Kiener has a very fine figure of this species.' "Columbella" bovini Kiener,^ a Panama shell, has strongly nodulous whorls and be- longs in a different section. It is interesting to note here that Pyrene rustica (Linnaeus), of the Mediterranean and west African coasts, in some of its variations is similar to P. fuscata (Sowerby). In general, fuscata tends to have a proportionately larger body whorl and lower spire, and it lacks the spiral sculpture entirely. The spiral sculpture on the lower part of the body whorl of rustica is variable in strength, however, and is entirely lacking in some speci- mens, while very strong on others. Pyrene rusticoides (Heilprin), originally described as a fossil, occurs in the Recent fauna of the Atlantic coast. It is clearly related to rustica; but, judging from shell characters, it is less closely related to the African shell than is fuscata. Some species of Pyrene have a plication on the columella deep within the aperture. This is often present on P. strombiformis. As pointed out by Dall for the Vobitidce, colu- mellar plications are the mechanical result of the folding of the mantle of the animal when it is drawn into the body whorl. The deeply placed columellar plications on P. strombiformis, P. major, and P. fuscata are variable in strength and position on the pillar. Often there is a double plication placed behind the denticulations and just above the point where the oblique truncation of the columella begins. Little systematic impor- tance should be attached to these rather indefinite, variable plications, which are merely a function of the amount of constriction and folding of the withdrawn mantle. ' Sowerby, Proo. Zool. Soc. London for June, 1832, p. 119. 2 Sowerby, Genera of Shells. No. 9, fig. 2, 1824. 'Kiener, Sp«c. Gin. Icon. Coq. Viv., Vol. 9, Cohimbelle. pi. 10. fig. 2, 1841. •Kiener, op. cit, p. 47, pi. 11, fig. 1, 1841. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 683 Subgenus COLUMBELLA Lamarck, 1799 Columbella Lamarck, "Prodrome," Mem. Soc. Hist. Nat. Paris, Ser. 1, Vol. 1, p. 70, 1709. Columbus Montfort, Conch. Syst., Vol. 2, p. 590, 1810. Type (by monotypy), Voluta mercatoria Linnseus. Shell like that of Pyrene, s. s., liut with spiral striations on the whole of the exterior. The only species given by Lamarck in his Prodrome under the new genus Columbella is Voluta mercatoria Linnseus, which is thus the type by monotypy. Eleven years later Denys de Montfort proposed the generic name Columbus, illustrating as type this same V. mercatoria L., which makes the later generic name an exact synonym of Colum- bella. The generic name Columbella Lamarck has been placed on the official list of genera by Opinion 94 of the International Commission on Zoological Nomenclature. ' Pyrene {Columbella) mercatoria (Linnseus) is a Recent species of the West Indies and Florida. We have carefully compared a series of specimens with Pyrene discors (Gmelin), the type of Pyrene, and have concluded that the differences in shell characters are not of generic importance. The only difTerence we have found to distinguish these two sub- genera is the relative strength or extent of the spiral sculpture, a character which is cer- tainly quite variable in many gastropods. Columbella, as properly restricted, is not represented in the Pliocene or Pleistocene, nor in the living fauna of the Pacific coast, so far as is known at this time. The well- known California Recent species commonly grouped under Alia and Astyris as sub- genera of Columbella belong to Risso's genus Mitrella. Columbella cosmia Dall,^ of the Pliocene marl of Shell Creek, Florida, is a Pyrene, s. s., and not a Columbella. Eurypyrene has been proposed by Woodring' to include the forms that have a wider aperture than Pyrene, se7isu stricto, the outer lip lacking the inward bulge. The interior of the outer lip has lirations instead of denticulations, and the posterior channel is wider and shorter and is bordered on the parietal wall by a callus ridge. This section is not present on the Pacific coast. Subgenus NITIDELLA Swainson, 1840 Nilidella Swainson, Treat. Malac, p. 151, fig. 17c, p. 313, 1840, Columbella nitida Lamarck, only species listed; Morch, Joum. Conchyl., Vol. 7 (Ser. 2, Vol. 3), p. 256, 1859. Type (by monotypy), Columbella nitida Lamarck, figured by Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 9, Columbelle, pi. 15, figs. 1, 1841. Like Pyrene, s. s., but shell thinner, more elongate ; inner Kp not incrusted with callus, columellar plications more evident. In his generic description Swainson mentions but one species, Columbella nitida Lamarck, which, in a footnote, he renames NitideUa marmorata, thus creating an exact synonym of Lamarck's species. Morch later considered Swainson's figure (p. 151, fig. 17c) a species distinct from Lamarck's nitida, which he accordingly named C. sioainsoni.* ' Smithsonian Misc. Coll., Vol. 73, p. 12, 1926. "- Figured in Trans. Wagner Free Inst. Sci.. Vol. 3, pt. 6, pi. 58, fig. 2, Sept. 30, 1903. 'Woodring, W. P., Carnegie Inst.. Publ. No. 385, p. 272, 1928, type by original designation Pyrene (Eurypyrene) eurynotum Woodring, op. cit., p. 272, a Miocene Caribbean species. * A comparison of Swainson's figure with Kiener's figure of nitida shows them to be conspecific. Reeve (Conch. Icon., Vol, 11, Columbella, pi. 11, figs. 52a-6, 1858) figures Sowerby's nitidula for Lamarck's nitida, but the differences are hardly specific. 684 San Diego Society of Natural History [ Memoirs Nitidella nitida (Lamarck), the type of this subgenus, is a West Indian shell which differs little from small specimens of P. discors. Aside from the differences mentioned above, the aperture of the type of Nitidella is not sinuous, the outer lip has less central thickening, and there are fewer whorls in the spire. The apex tends to become blunt in many specimens. Nitidella is clearly a connecting link between Pyrene and Mitrella. While there seems to be little connection between the heavy-shelled, thick-lipped Pyrenes having nar- row, sinuous apertures, such as P. labiosa, P. paytensis, and P. major, on the one hand, and the thin-shelled Mitrellas, such as M. scripta and M. elegans, on the other, the ex- tremes merge gradually into each other through numerous intermediate species. Thus P. discois, the type of Pyrene, is clearly related to the group with the extremely thick- ened lip through such species as fuscata. In the other direction, P. discors is related through P. nitidula Sby. to P. nitida; and this latter species has a variant with an oval aperture and a columella on which the plication is obsolete or reduced to a low ridge on the lower margin. Some of these variants could be placed in Mitrella without unduly extending the limits of that genus. Such connecting links between related genera occur frequently and make the selection of sharp generic division lines either impossible or purely a matter of convenience and personal judgment. We have retained Nitidella because it seems to represent a minor gi-oup that is recognizable to one who has become familiar with the family. As the type of Nitidella shows greater similarity to the type of Pyrene than to the type of Mitrella, it seems better to assign Nitidella to the former. On the Pacific coast there appears to be no fossil representative of Nitidella as prop- erly restricted. "Nitidella" gouldii Carpenter is a Mitrella, although it is a step toward N. nitida from M. scripta. We have not seen specimens of Mitrella lutulenta (Dall), doubt- fully referred to Nitidella by its author, but the description suggests that it is a Mitrella. Carpenter at an early date introduced the name Nitidella into Pacific coast usage because Gray had used it for Columbellas with Purpuroid opercula and it seemed to afford a place for cribraria Lamarck. Genus ANACHIS H. and A. Adams, 1853 Anachis H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 184, 1853, list includes Columbella scalarina Sowerby; Chenu, Man. Conchyl., Vol. 1, p. 202, 1859; Tate, Appendix to Woodward's Man. Moll., Ed. 3, p. 13, 1875 (also Ed. 4, p. 13, 1880), type cited, Columbella scalarina Sowerby; Tryon, Man. Conch., Ser. 1, Vol. 5, pp. 102, 152, 1883; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 236, 1901, type stated to be Columbella rugosa Sby.; Wood- ring, Carnegie Inst., Publ. No. 385, p. 276, 1928, type Columbella scalarina Sowerby. Atilia H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 184, 1853, list includes Columbella suffusa Sowerby; Chenu, Man. Conchyl., Vol. 1, p. 201, 1859; type (here designated) Columbella suffusa Sowerby. Type (by subsequent designation, Tate, 1875), Columbella scalarina Sowerby, fig- ured by Sowerby, Thes. Conch., Vol. 1, Columbella, pi. 39, fig. 118, 1844; and by Reeve, Conch. Icon., Vol. 11, Columbella, sp. 11, pi. 3, figs. 11a, 11&, 1858; and by Tryon, Man. Conch., Ser. 1, Vol. 5, pi. 54, fig. 39, 1883. Shell like that of Pyrene but with axial ribs and in many cases smalk'r. Geologic range: Miocene to Recent (? Eocene of Australia). Distribution: Tropical and temperate seas. The first valid type designation for this genus seems to be that of Tate, who chose Columbella scalarina Sowerby. This species is like some of the tabulated Pyrenes but has strong axial sculpture. The tabulation or shoulder on the upper margins of the whorls is a variable character in this family and should be regarded as of little more Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 685 than specific value. We therefore use Anachis, sensu lato, to include both the tabulated forms and the smooth ones. Atilia H. and A. Adams, of which the type^ is C. suffusa Sowerby, is a synonym of Anachis. It can not well serve as a section to include the un- tabulated species, since C. suffusa has a small shoulder on the body whorl. Such a division of the genus would only lead to confusion. Carpenter^ stated that Anachis was characterized by an operculum similar to that of Pisania; but as opercula are not well known even in living shells and in this case do not seem to be significant, the more enduring shell characters are given more weight. Subgenus ANACHIS, s. s. Shell relatively large, short, typically with flattened whorls, shouldered near the suture ; aperture subquadrate, outer lip thickened and denticulate, mner lip often with a callus deposit, denticulate or lirate. The typical subgenus differs from Chauvetia in the relatively lower spire and in general in the larger, heavier shell. The species of Chauvetia usually have more pro- nounced spiral sculpture than typical Anachis. Anachis gaskoini Carpenter, is figured on plate 26, figure 47, to illustrate the form of typical Anachis. Anachis (Anachis) coronata (Sowerby) Columbella coronata Sby., Proe. Zool. Soc. London for 1832, p. 114, 1832; Thes. Conch., Vol. 1, Columbella, p. 135, sp. 70, pi. 39, fig. 134, 1844. Type specimen: In the British Museum. Type locality: Gulf of Panama; Recent. Pleistocene: Scammons Lagoon, Lower California, Mexico (coU. San Diego Society Nat. BUst.). Recent: Magdalena Bay to Ecuador. This species is quite variable in the development of the axial sculpture. A series of Recent specimens from the west coast of Lower California shows a variation from rounded nodes on the upper shouldered part of the whorls to elongate axial ribs extend- ing down the side of the whorl and varying considerably in number on different speci- mens from the same locality. The fossil specimens providing the Pleistocene record given above are on an average somewhat larger than Recent individuals, the largest being nearly 10 millimeters long. They are slightly tabulated below the suture and the axial ribs are nodose on the shoulder of the body whorl. Anachis (Anachis) solidula (Reeve) variety praecursor (Arnold) Columbella solidula Reeve, var. prscursor Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 236, pi. 10, fig. 4, 1903. ' 'Shell small, broadly fusiform ; spire elevated ; apex rounded, whorls seven, only slightly convex, slightly shouldered above, smooth ; body whorl two-thirds length of shell, with row of nodes on shoul- der, each node being the termiaation of a faint transverse ridge which becomes obsolete on lower portion of whorl; columella with spiral sulcations on exterior; aperture rhomboidal, narrow; outer lip thickened internally by row of prominent teeth; iimer lip smooth; canal short, recurved. "Dmiensions. — Long. 14.5 nun.; lat. 65 mm.; body whorl 10 mm.; aperture, including canal, 7.5 mm. ; canal 1 mm. ; defl. 42 degrees." (Arnold, 1903.) * Cossmann, Ess. Pal6o. Comp., Vol. 4, p. 242, 1901, states the type to be Mitrelta minor Scaechi, but that species is not in the original list of species assigned to the genus by its authors and can not serve as type. As the citation by Pace. 1902, of C. suffusa may be ruled out on a technicality, we have definitely designated that species here. - Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 505. 1857. 686 San Diego Society of Natural History [Memoirs Type specimen: In the U. S. National Museum. Type locality: "Upper San Pedro series at San Pedro," California, Pleistocene. Pleistocene: Upper San Pedro series (Palos Verdes formation) at San Pedro (Arnold) . Only the type specimen of this variety has been reported. Arnold's description and figure suggest that it is very close to the typical variety and that Arnold's varietal name should be discarded. The description mentions the rounded apex, which is not thus shown in the figure. Reeve's description of the type of solidula^ gives that shell a sharp spire; but a specimen apparently of solidula in the Oldroyd Collection at Stanford Uni- versity has a decidedly obtuse apex; in fact, the nucleus is depressed, giving the spire a truncated appearance. The few widely spaced spiral striations below the suture on this specimen are quite faint and would undoubtedly be effaced if subjected to erosion. Arnold's description and figure do not include these striations. Subgenus CHAUVETIA Monterosato, 1884 Lachesis Risso, Hist. Nat. Eur. Merid., Vol. 4, p. 211, 1826; Buequoy, Dautzenberg, and Dollfus, Moll. Mar. Rous- sillon, Vol. 1, p. 112, 1883; not Lachesis Daudin, 1804 (Reptilia). Nesxa Risso, op. cit., p. 223, pi. 5, fig. 69, 1826; Buequoy, Dautzenberg, and Dollfus, op. cit., p. 112, 188.3; not Nessea Lamour, 1812. Donovania Buequoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, p. 112, "Type: D. minima" Montagu, pi. 15, figs. 26-32, 1883; not Donovania Leach, Brewster's Edinburgh Encyclopedia, Vol. 7, p. 435, 1814. ? FolinBcta Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 136, 1884, type by virtual tautonomy and .subsequent designation (Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 326, 1918) Buccinum lefebvrii Moravigna, 1840, + "Buc- cinum" folinex Philippi, non DeUe Chiaje, this species being in the original list. Chauvetia Monterosato, op. cit., p. 137, 1884, type by original designation, "Buccinum" candidissimum Phihppi; Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 323, 1918. ? Nassarina Dall, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 18, p. 181, 1889, type by original designation, Nassarina bushii Dall, Recent West Indies and Florida, figured in U. S. Nat. Mus., Bull. 37, pi. 15, fig. 12, 1903; Wood- ring, Carnegie Inst. Wash., Publ. No. 385, p. 279, 1928. Folinia Monterosato, 1890, not Folinia Crosse, 1868. Syntagma Iredale, Proc. Malac. Soc. London, Vol. 13, p. 34, 1918, new name for Donovania Buequoy, Dautzenberg, and DoUfus, Moll. Mar. Roussillon, Vol. 1, p. 112, 1883; type Buccinum. brunneum Donovan, 1803, + Buc- cinum minimum Montagu, 1803. (If brunneum is on pi. 179 of Donovan's Hist. Nat. Brit. Shells as cited by Forbes and Hanley, that is in the last part of Vol. 5, it appeared, according to the Cat. Nat. Hist. Books Brit. Mus., about June, 1804, and Montagu's name has priority.) Type (by original designation), Buccinum candidissimum Philippi. The shells of this subgenus are usually smaller, higher spired, with a more slender columella and thinner outer Up than those of typical Anachis. The outer lip usually, but not always, lacks denticulations. Chauvetia is distinguished from Mangelia by the shorter columella, which is truncated or twisted at the end, by the somewhat notched anterior canal, and by the more rounded aperture and the presence of an operculum. Aesopus is very different in sculpture. Anachis (Chauvetia) lineolata (Gray in Reeve) Plate 26, Figures 31, 34 Pleuroioma lineolata Gray MS8., Reeve, Conch. Icon., Vol. 1, Pleurotoma, pi. 37, fig. 337, 1846. Not Lachesis lineolata Tiberi, Journ. de Conchyl., p. 76, pi. 5, fig. 5, 1868, a color variety of candidissima Philippi. Clalhurella lineolata Gray, Tryon, Man. Conch., Vol. 6, p. 295, pi. 21, fig. 14, 1884. Mangilia lineolata Reeve, Dall, Bull. 112 U. S. Nat. Mus., p. 82, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 144, 1927. Anachis minuta T. S. Oldroyd, Nautilus, Vol. 34, p. 114, April, 1921, not Coluinbclla (Anachis) miniita Gould, Proc. Bost. Soc. Nat. Hist., Vol. 7, p. 334, 1860. ' Reeve, Conch. Icon., Vol. 11, ColumbeUa, sp. 149, Feb., 1859. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 687 Shell small, thick for its size, high spired; whorls rounded, sutures not deep, the whole surface of the shell sculptured with strong spiral cords, three or four showing on the spire whorls and nine or ten on the body whorl, axial riblets weaker, about 12 to a whorl, low, rounded, narrower than the interspaces; aperture short, narrow, rounded at the posterior end, outer lip at some stages of growth with two or three obscure denticles, columella straight in the upper portion but sometimes strongly twisted to the left at the lower end, anterior canal short, narrow, notched behind. Dimensions: Altitude 5 mm., length of aperture 1.7 mm., diameter of body whorl 1.8 mm. Pleistocene: Upper Pleistocene at Santa Monica, Los Angeles Co. (T. S. Oldroyd). Living: Catalina Island to Panama and the Galapagos Islands (Dall). This species is easily distinguished by its strong spiral cords. Its notched anterior canal and the denticles on the interior of the outer lip show it to be a Chauvetia instead of a Mangelia. Reeve's figure is very poor, not showing the sculpture properly (as Reeve remarks himself), and showing the aperture relatively too long. The writers do not know upon what basis the identification of Reeve's name with the Pacific coast shell was made; but since the identification has been made, they are inclined to follow it until definite evidence is produced to show that it is wi'ong. A. penicillata has stronger axial ribs, a thinner shell, and usually a trace of a shoulder at the top of the whorl. Anachis (Chauvetia) penicillata Carpenter "? Anachis" penicillala Carpenter, Brit. Assn. Adv. Sci., Kept, for 1S63, pp. 537, 664, 1864, reprinted in Smithsonian Misc. Coll., No. 252, pp. 23, 150 (bottom pagination), 1872; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 398, 1865, reprinted in Smithsonian Misc. Coll., No. 252, pt. K, p. 288 (bottom pagination), 1872. Colun^ella penicillala Carpenter, Tryon, Man. Conch., Ser. 1, Vol. 5, p. 177 (unfigured), 1883; T. S. Oldroyd, Nau- tUus, Vol. 25, no. 7, p. 74, 1911; Lowe, Nautilus, Vol. 27, no. 3, p. 27, 1913. Anachis penicillala Carpenter, Baker, Nautilus, Vol. 16, p. 40, 1902; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, p. 12, 1924; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 1, p. 270, 1927. Columbella (Anachis) penicillata Carpenter, Dall, Bull. 112, U. S. Nat. Mus., p. 103, 1921. Shell small, long, high spired; whorls six, convex, regularly enlarging, slightly shouldered below the suture ; sutures linear, depressed ; sculpture consisting of promuient romided axial ribs, number- ing about 14 on the body whorl, contmuous from suture to suture, fading out gradually on the lower part of the body whorl, crossed by continuous, evenly spaced, roimded spiral threads, which some- times give a beaded effect to the axial ribs ; aperture about one-third of the total length of the shell, ovate-subquadrate ; outer lip simple, not denticulated, with a very shallow, broad, indented sinus below the suture ; columella without denticulations or plications, sometimes polished at the inner lip; anterior canal short, slightly notched behmd. Dimensions: Altitude 6 mm.; chameter 2.2 mm. Type specimen: Formerly in the "Coll. Boyce, Utica, N. Y."; present location unknown. Type locality: "Santa Barbara, San Diego, Catalina Island." Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd); upper San Pedro, Signal HiU, Los Angeles County (T. S. Oldroyd collection). Recent: Santa Barbara, California, to GuU of California, Mexico (DaU, 1921). This species is easily distinguished from subturrita Carpenter' by its more elongate aperture, longer columella, and stronger sculpture. A. subturrita has an unusually short columella. A. pulchrior (C. B. Adams) is a broader, relatively lower spired form which frequently has teeth on the in.side of the outer lip. Specimens of this last species from San Hipohte Point, Lower California, show much variation in strength of sculpture, some individuals having very low axial ribs and the spiral threads obsolete except on the base of the body whorl. C. B. Adams- described this shell as having a "surface smooth and shining"; but the specimens we have seen are not quite typical, the nearest having reduced sculpture mentioned above. 1 Carpenter, Proc. Calif. Acad. Sci., Vol. 3, p. 223, 1866. Anachis peiraris Dall (Proc. U. S. Nat. Mus., Vol. 34, p. 250. 1908) is a synonym. A. subturrita is figured by Tryon, Man. Conch.. Ser. 1, Vol. 5, pi. 58, fig. 47, 1883. - Columbella pulchrior C. B. Adams, Ann. Lye. Nat. Hist. N. Y., Vol. 5. (p. 96 of the separate), 1852. 688 San Diego Society op Natural History [Memoibs Anachis (Chauvetia) amoldi (Dall) Columbella (Anachis) minima Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 237, pi. 9, fig. 8, 1903. Not Columbella minima Tenison-Woods, 1878 (error for minula Angas), nor of Bucquoy, Dautzenberg, and Dollfus, 1882, nor of Sacco in Bellardi, 1890, nor of J. Hervier, 1899. Columbella (Anachis) amoldi Dall, Proc. U. S. Nat. Mus., Vol. 34, p. 250, 1908, new name; Hanna, Proe. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 163, 192-4. "Shell small, resembles a yoimg Amphissa corrugata but much slenderer; surface sculptured by numerous transverse ridges and fine spiral sulcations ; whorls six, shouldered above as in Amphissa versicolor; aperture subquadrate; outer lip nearly straight; pillar straight, spirally striated. "Dimensions. — Long. 6 mm.; lat. 2.4 mm.; body whorl 3.5 mm.; aperture 2.2 mm.; defl. 28 degrees." (Arnold, 1903.) Type specimen: In the U. S. National Museum. Type locality: Upper San Pedro series of San Pedro; Pleistocene. Pleistocene: At the type locality, rare (Arnold). Arnold's figure is of a shell somewhat resembling in shape Recent specimens in the Oldroyd Collection at Stanford University, labeled " Columbella fluctuata" Sowerby, from San Ignacio Lagoon, Lower California, Mexico; but neither Arnold's figure nor descrip- tion indicates the presence of teeth on the outer lip, which are present in the Recent species, and the spiral sculpture on Arnold's figure is shown all over the shell. Notwith- standing the Amphissa-\ike characteristics, the species may belong to Anachis. We have seen no specimens. The following is a list of the Recent species of Anachis reported from the Pacific coast of North America, with their geographic range so far as known: A. adelince Tryon, 1883. West Mexico. A. albonodosa Carpenter, 1857. Mazatlan. A. atramentaria Sowerby, 1844. Panama and Galapagos. A. bartschii Dall, 1916. Gulf of California (= ? toEniata Phil.) A. coronata Sowerby, 1832 (not of Seguenza, 1880, = C. bronni Mayer, 1869). Gulf of California to Panama. A. cruentata Morch, 1860. Central America. ^4. diminula C. B. Adams, 1852. Gulf of California to Panama. A. elegantula'NloTch, 1861. Central America and Galapagos. A. encaustica Reeve, 1858. GuK of California. A. fluctuata Sowerby, 1832 (-|- saturalis Gray, 1834), Gulf of California to Peru. A. fulva Sowerby, 1832 (not of Brusina, 1870). Mazatlan to Panama. A. fuscostrigata Carpenter, 1864. Cape San Lucas. A. fusidens Da\\, 1908. Galapagos. A. gaskoini Carpenter, 1857 (-f- C. tmniata Philippi, 1846, not Lmk, 1807 + ? bartschii T)a\\, 1916). Point Abreojos, Lower California, to Acapulco and Peru. A. humerosa Carpenter, 1865. Acapulco, Mexico. A. lineolata Gray in Reeve, 1846. Catalina Island to Panama and Galapagos. A. lentiginosa Hinds, 1844 (-|- tessellata C. B. Adams, 1852, not Dunker, 1871; + guatemalensis Reeve, 1859; not lentiginosa Reeve, 1859). Panama to Peru. .4. milium Dall, 1916 (+ Columbella (Anachis) parva Sowerby, 1844, not "Buccimnn" pnrnim H. C. Lea, 1841, nor Columbella (Anachis) parva, Sacco in Bellardi, 1890). Gulf of California to Ecuador. A. moesta C. B. Adams, 1852. Panama. A. nigricans Sowerby, 1844. Gulf of California to Panama and Galapagos. ^4. nigrojusca Carpenter, 1857. GuK of California; west coast of Mexico. A. nigropunctata Sowerby, 1832. Galapagos. A. pachyderma Carpenter, 1857. Mazatlan. A. pariolida Duclos, 1835 (April, 1840). Central America ? Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 689 A. penicillata Carpenter, 1864. Santa Barbara, California, to Gulf of California, Mexico. A. phanea Dall, 1919. Salina Cruz, Mexico. ,4. pidchrior C. B. Adam.s, 1852 (? not of Carpenter, 1864). Point San Hipolito, Lower California, to Panama. A. pygmcea Sowerby, 1832 (not of Bellardi, 1890). Point Abreojos, Lower California, to Peru. A. reedi Bartsch, 1928. Bay of Guayaquil, Ecuador. A. reevei Carpenter, 1864 (see A. santa-barharensis Carpenter, 1864). A. rufotinda Carpenter, 1857. Point Abrejos, Lower California, to Panama. A. rugosa Sowerby, 1832. Panama. A. rugulosa Sowerby, 1844. Gulf of California to Peru and the Galapagos. A. santa-barbarensis Carpenter, 1856. (Carpenter renamed this species reevei in 1864 because it was foimd not to occur at Santa Barbara, California; but although reevei is now the better knowTi name, the origmal will have to take its place, if the rules are to be followed). Gulf of California to Acapulco, Mexico. A. scalai-ina Sowerby, 1832 (+ costellafa C. B. Adams, 1852, not of Broderip and Sowerby, 1829). Magdalena Bay, Lower Cahfomia, and Gulf of California to Panama. A. serrata Carpenter, 1857. Magdalena Bay, Lower California, to Gulf of California. A. solidula Reeve, 1859. Magdalena Bay to Ecuador. A. spadicea Philippi, 1846. Mazatlan. A. strongi Bartsch, 1928. Guayaquil Bay, Ecuador. A. subtiirrita Carpenter, 1866. San Pedro, California, to Todos Santos Bay, Lower California, Mexico. .4. suffusa Sowerby, 1844. Central America to Panama; Galapagos. ,4. sulcosa Sowerby, 1832. Panama, Galapagos. A. terpsichore, "Leathes," Sowerby, 1822 (not Menke, 1851, nor Kiener, 1841; + lyrata Sowerby, 1832). Lower California, Mexico, to Peru. ^4. tincta Carpenter, 1864. Cape San Lucas, Lower Cahfomia; ? Galapagos. A. varia Sowerby, 1832. Gulf of California to Panama. A. varians Sowerby, 1832 (not varimis Hutton, 1885). Galapagos. A. varicosa Gaskom, Oct. 28, 1852. Gulf of California, Mexico, to Chile. A. lohitei Bartsch, 1928. Guayaquil Bay, Ecuador. Such a list indicates that many names need to be synonymized. Genus MITRELLA Risso, 1826 Mitrella Risso, Hist. Nat. Eur. Merid., Vol. 4, p. 247, 1826, list comprises M. flaminea Risso, M. levigata Risso, M. coslulala Risso, and M. tvrgidida Brocchi; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 235, 1901, type cited, Murex scriplus Linnaeus; Pace, Proc. Malac. Soe. London, Vol. 5, p. 44, April, 1902; Co.x, Rept. Pal. Zanzibar, Moll., p. 28, 1927, type cited M. flaminea Risso; Woodring, Carnegie Inst., Publ. No. 385, p. 273, Nov., 1928, type, Mitrella flaminea Risso (= Murex scriptus Linnaeus). Not Mitrella Swainson, Elem. Conch., 1835, = Sivainsonia H. & A. Adams, 1853. Alia H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 183, 1853, li.st includes C. carinata Hinds; Morch, Journ. Conchyl., Vol. 7, (Ser. 2, Vol. 3), p. 257, March, 1859; Chenu, Man. Conchyl., Vol. 1, p. 201, 1859, example, C. uni- fasciata Sowerby; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 232, 1901, tjrpe cited, Columbella carinata Hinds; Pace, Proc. Malac. Soc. London, Vol. 5, p. 41, April, 1902. Astyris H. and A. Adams, Gen. Rec. MoU., Vol. 1, p. 187, 1853, list includes Columbella rosacea Gould; Morch, Journ. Conchyl., Vol. 7, (Ser. 2, Vol. 3), p. 257, 1859; Tryon, Struct. Syst. Conch., Pt. 2, p. 179, 1883, C. clausilisejormis Kiener, listed; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 238, 1901, type Columbella rosacea Gould; Pace, Proc. Malac. Soc. London, Vol. 5, p. 42, 1902. "Mitsella Risso" Morch, Journ. Conchyl., Vol. 7 (Ser. 2, Vol. 3), p. 257, 1859, misspeUing for Mitrella. 1 Aldra H. Adams, Proc. Zool. Soc. London for 1860, p. 450, A. elegans H. Adams, monotype. Columbellopsis Bucquoy, Dautzenberg, and DoUfus, Moll. Mar. Roussillon, Vol. 1, p. 77, 1882, Columbella minor Scacchi designated as t3T)e, figured on pi. 13, figs. 9 and 10; Cossmann, Ess. Paleo. Comp., Vol. 4, p. 242, 1901; Pace, Proc. Malac. Soc. London, Vol. 5, p. 43, 1902; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 274, 1928. ? Angulatomitrella Sacco, 1889, fide Cossmann, p. 235, 1901. ? Arcuatomitrella Sacco, 1889, fide Cossmann, p. 235, 1901; Pace, Proc. Malac. Soc. London, Vol. 5, p. 42, 1902, type, C. prsecedens Bellardi. ? Fluella Dall, Proc. Biol. Soc. Wash., Vol. 37, p. 87, 1924, type, Astyris {Fluella) vidua Dall. .? Plectaria DaU, Proc. Biol. Soc. Wash., Vol. 37, p. 87, 1924, type, Astyris (Plectaria) crumena Dall. 690 San Diego Society of Natural History [Memoirs Type (by subsequent designation, Cox, 1927), M.fiaminea Risso = Murex scriptus Linnseus. Shell of medium weight, rather high spired, acutely conical; whorls almost flat to moderately ventricose, sutures linear, slightly impressed; spiral sculpture confined to basal portion of body whorl (typically) or uniform over entire shell; aperture small, elongate-ovate, one-half or less the length of the shell ; outer lip sometimes thickened and denticulate or lirate withm ; umer hp with or without lirations or denticulations on columella, which is short or obhquely truncated ; anterior canal hardly or not at all differentiated from the basal portion of the aperture; posterior canal undeveloped or represented by a slight flare or shallow channel on the outer lip at junction with body whorl. Size generally small. Geologic range: Oligocene to Recent. Distribution: World wide. This genus was established by Risso in 1826, the firet species in his list being M. flaminea (figure 144), which has generally been considered the genotype. Risso's figure is clearly recognizable as Murex scriptus Linnseus, and it has been con- sidered as such by subsequent authors. Morch, in his paper on the lingual dentition of the ColumbeUidce (1859), points out that Risso's generic description accords very well with the first species "C. scripta L. (B. Linncei Payr.) qui doit etre regard^e comme le type." Cossmann likewise cited Murex script^is Linnseus as the type, but like Morch, made no mention of Risso's original name. These type designations probably will not hold, since Risso's specific name is not mentioned, although Morch indirectly indicated it by his reference to the "first ""^dirTcripia (Lin- species." Gray,' in his synonymic type list of 1847, does not help out nsBUB), Recent speci- jj^ ^j^jg gase, merely citing "flammea" under Columbella and most of men in the Oldroyd ' •' ... • i i Conrad, T. A.. Proc. Acad. Nat. Sci. Phila. for 1862, pp. 287, 564. > Whitfield, R. P., Mon. 24, U. S. Geol. Surv., pi. 29, figs. 12-15, 1894. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 695 Mitrella gouldii (Carpenter) "? Niiidella" gouldii Carpenter, Proc. Zool. Soc. London for 1856, p. 208, 1857. Not Columhella gouldii Agassiz MS., Reeve, Conch. Icon., Vol. 11, Columhella, sp. 135, Nov., 1858. Niiidella gouldii Carpenter, Brit. Assn. Adv. Sci., Kept, for 186.3, p. 66.3, 1864; Dall, Bull. 112, U. S. Nat. Mus., p. 104, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, p. 12, Jan., 1924; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 98, March, 1924; Stanford Univ. Publ. Geol., Vol. 2, Pt. 1, p. 277, 1927. Columhella (Niiidella ?) dalli, E. A. Smith, Ann. Mag. Nat. ffist., Ser. 5, Vol. 6, p. 287, 1880. Astyris gouldi Carpenter, Baker, Nautilus, Vol. 16, p. 40, 1902. Niiidella gouldi Carpenter, Dall, Nautilus, Vol. 30, p. 26, 1916. Columhella (Astyris) cmislaiUia Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 53, pi. 1, figs. 7a, 7b, Oct., 1916. Type specimens: Of gouldii, in the Gould collection (Albany ?) ; of dalli, in the British Museum; of constantia, at the University of California. Type localities: of gouldii, Santa Barbara, California, Recent; of dalli, Vancouver Island, British Columbia, Recent; of constantia, Fourth Street and Broadway, Los Angeles, California, upper Pliocene. Pliocene: "Fernando" of Fourth and Broadway, Los Angeles, upper Pliocene (Moody); Capitola, Monterey Co. (collection at Stanford University). Pleistocene: Lower San Pedro fauna (lower Pleistocene) of Nob Hill cut, San Pedro (I. S. Oldroyd). Recent: Kodiak, Alaska, to San Diego, California. This species is similar to M. carinata var. gausapata (Gould) in shape; but the body whorl is somewhat more ventricose just above its base, the spire is usually relatively lower, and the denticulations on the inner side of the outer lip are apt to be deeper within the aperture and are frequently absent altogether. It is comparatively large and thin- shelled. The anterior canal is more clearly differentiated from the aperture than in gausapata. While these two species are similar in general appearance, they can usually be separated by these characters. When specimens of gouldii are held so that a strong hght falls directly upon the spire, a shadow begins abruptly on the lower portion of the body whorl and brings out the low carina in that region. Columhella constantia Moody, described from the upper Pliocene of Los Angeles, is undoubtedly M. gouldii. We have examined the type specimen. Specimens with an in- complete outer lip appear to have an unusually long anterior canal, and this imperfection in fossils is frequently quite misleading. The specimens collected by T. S. Oldroyd from the Pleistocene of Nob Hill, San Pedro, California, are rather small in comparison with recent specimens from Alaska, some of which reach 15 mm. in length. The margin of the oblique truncation on the lower part of the columella of gouldii has a small, low ridge or marginal plait which is unhke the plication on the columella of typical Nitidella nitida (Lamarck), and gouldii is probably not genetically related to Nitidella. The shape of the entire shell and particularly the oval aperture require its being placed with Mitrella. The collections at Stanford University contain a considerable number of specimens of Mitrella, labeled Astyris gausapata Gould, A. richthofeni Gabb, and Columhella richthofeni Gabb from the Merced and Purisima formations (Pliocene) of San Mateo County, California, and from the upper Pliocene of the mouth of Elk River, Oregon. Most of these specimens can be classified as Mitrella carinata var. gausapata (Gould), but some have the characters of Mitrella gouldii (Carpenter). It appears probable that M. gouldii separated from gausapata in the late Pliocene, the collections suggesting that the gouldii form occurred as individual mutants or variants along with the parent stock of gausapata. The separation of the two forms is difficult in the PHocene, and when the specimens are imperfect distinction is impossible. 696 San Diego Society of Natural History [ Memoirs Mitrella grandior, new species Plate 26, Figure 46 Shell large, heavy, elongate, spire high; whorls about five, slightly ventricose; sutures linear, slightly depressed; sculpture absent except for a few faint, low, wide spiral cords on the base of the body whorl; aperture less than half the length of the entire shell, elongate-ovate; outer lip (incom- plete) simple, no flare or shoulder at the posterior end; iimer lip with a slight callus deposit on the columella; columella (incomplete) nearly straight, without denticulations; anterior canal missing on the tjTJe. Length (incomplete), 22 mm.; width, 9.5 mm. Type specimen: No. 6, Invertebrate Paleontology Collection, San Diego Society of Natural History, San Diego, California. Type locality: San Diego Society of Natural History locality 221, second conglomerate ridge on the east side of Canada de Aliso, north of Canada Larga about one-quarter mile, Ventura County, California, middle (or upper ?) Pico, Pliocene, collected by H. R. Gale. Pliocene: Type locality only, middle (or upper Pico) ; one specimen. The high spire, ovate aperture, and lack of sculpture except on the base of the body whorl in back place this species in Mitrella. It is very much larger and heavier than types of gausapata and richthofeni, both of which were said to be a half inch in length. Gabb's largest specimen of richtliofeni^ was "about .5 inch." We have examined several hundred fossil specimens of the gausapata group in the collections at Stanford University and while the average length is considerably less than a half inch, two or three specimens of gausapata approximate that size. There were none over half an inch long. M. grandior appears to resemble very closely M. erythrostoma (Bonelli),- an extinct European species occuring in the Red Crag (upper middle Pliocene) of England and the Pliocene of Italy. The latter species is well figured by Harmer' in his monograph on the Crag mollusca. The chief difference between the two species is that M. grandior has a proportionately larger bodj' whorl. In grandior the enlargement of successive whorls appears to have been suddenly accelerated when the ultimate whorl was reached, whereas the Crag species shows a more uniform enlargement during growth. These differences in some species are within the limits of individual variation. Mitrella ocellata (Gmelin) Volvta ocellata Gmelin, Syst. Nat., Ed. 13, p. 3455, I79I. Bucciniim crihrarium Lamarck, Hi.st. Nat. Anim. s. Vert., Vol. 7, p. 274, 1822. Columbella gvltata G. B. Sowerby, Proc. Zool. Soc. London for 1832, p. 118, fide Sowerby, Thes. Conch., Vol. 1, Colmnbella, p. 129, 1844; not of G. B. Sowerby, Proc. Zool. Soc. London for 1844, p. 50, = C. punctata Sowerby, 1844 ( = ? C.fasdata Sby.) ; C. B. Adams, Ann. Lye. Nat. Hist. N. Y., Vol. 5 (p. 89 of the separate), 1852. Columbella cribraria Lamarck, Sowerby, Thes. Conch., Vol. 1, Columbella, p. 129, sp. 51, pi. 38, fig. 112 (113 jun.), 1844; Tryon, Man, Conch., Ser. 1, Vol. 5, p. 122, pi. 48, figs. 73-77, 1883. Columbella argus A. d'Orbigny (d'Orb., 1840) in Sagra, Hist. Isla Cuba, Pt. 2, Vol. 5, pp. 233, 234, pi. 21, figs. 34, 36, 1845. Buccinum -panndum Dunker, Zeit., ftr Mai., p. 64, 1847. Nitidella cribraria Lamarck, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 487, 1857. Nitidella ocellata Gmelin, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 217, 1909; NautUus, Vol. 30, p. 26, 1916; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Nitidella crebraria Gmelin, Zetek, MoU. Rep. Panama, p. 23, 1918 (= N. cribraria Lamarck). •Geol. Surv. Calif., Pateo., Vol. 2. p. 10, 1866, figured on pi. 2. fig. 16. ^Columbella erytliTosloma Bonelli. MS. Cat. Mus. Zool. Torino, 1825; Bellardi, Men. Columbelle, p. 9. pi. 1, figs. 4, 5, 1848. •Men. Pateo. Soc, Vol. 70, Plio. Moll. Gt. Brit.. Vol. 1, pt. 3. p. 306, pi. 33, figs. 11, 12, 1918; also figured by Cerulli-Irelli, Palffio. Ital. Vol. 17, p. 256, pi. 23, figs. 64, 64a. 1911. VoLTtME I ] Pliocene and Pleistocene Mollusca of California 697 Shape like that of M. cariiiata gausapata (Gould) but with thicker, heavier shell and with the pillar often a little longer than the anterior margin of the outer lip and lackmg the small crenulations or denticulations that are sometimes present on gausapata; the apex sometimes (or always ?) blunt. Pleistocene: "Upper Quaternary" at San Igiiacio Lagoon, Lower California, Mexico (E. K. Jordan). Recent: Magdalena Bay, Lower California, to Guayaquil, Ecuador, and the Galapagos; West Indies. ^ There has been uncertainty over the recognition of Gmelin's species, as the. type specimen and the type locality are both unknown. Tryon, Dall, and others have con- sidered Lamarck's Buccinum cribrarium conspecific. This name was applied by Lamarck to a species reputed to have come from Java, and it seems doubtful if that same species occurs also in the West Indian and west American regions without showing some varietal differences. Under the circumstances, we have used the oldest name for the American species. Mitrella tuberosa (Carpenter) Plate 26, Figure 45 Amycla tuberosa Carpenter, Brit. ,\ssn. Adv. Sci., Rept. for 1863, pp. 539, 628, 662, 1864; .\nnals and Mag. Nat. Hist., Ser. 3, Vol. 15, p. 398, May, 1865; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 229, 1888. Astyris tuberosa Carpenter, Stearns, Proe. Calif. Acad. Sci., Vol. 5, p. 81, 1873; Keep, West Coast Shells, p. 36, 1888, 1892; Kelsey, Nautilus, Vol. 12, p. 89, 1898; Baker, Vol. 16, p. 40, 1902. Columbella tuberosa Carpenter, Tryon, Man. Conch., Ser. 1, Vol. 5, p. 135, pi. 50, figs. 40, 41, 1883; Lowe, Nautilus, Vol. 18, p. 19, 1904; Berry, Vol. 21, p. 41, 1907; Vol. 22, p. 38, 1908; T. S. Oldroyd, Vol. 28, p. 82, 1914; Willett, Vol. 33, p. 22, 1919; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 1, p. 271, 1927. Columbella (Astyris) tuberosa Carpenter, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 213, pi. 20, fig. 6, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 240, pi. 10, fig. 7, 1903; Keep, West American Shells, p. 187, 1904. Columbella (Alia) tuberosa Carpenter, DaU, BuU. 112, U. S. Nat. Mus., p. 103, 1921. Columbella (Alia) tuberosa var. major T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, pp. 12, 24, 1924; not Columbella major Sowerby, 1832; nor Columbella scripta (Linnseus) var. major Monterosato, Giorn. Soc. Palermo, Vol. 13, p. 104, 1878; nor Columbella rustica (Linnseus), var. major Pallary, 1900. Shell like that of gausapata but smaller, more elongate, with relatively higher, more slender spire, and with a low carina or angle just below the middle of the body whorl. Type specimens: Of tuberosa, in the British Museum ?; of major, in the U. S. National Museum, No. 352,369. Type localities: Of tuberosa, Santa Barbara, Recent; of major, lower Pleistocene of Nob Hill cut, San Pedro, Los Angeles County, California. Miocene: Doubtfully in the S.an Pablo formation, upper Miocene of California, (Clark); Superior Oil Com- pany's well, .\nsolabehere No. 1, four or five miles north of Bakersfield, depth 4,525 feet, Santa Margarita formation, upper Miocene (H. R. G.). Pliocene: San Diego well in Balboa Park, San Diego, San Diego formation, middle Pliocene (Dall; .\rnold); Bath-house Beach, Santa Barbara, Santa Barbara formation, upper Pliocene (Berry); upper Plio- cene (Santa Barbara zone) at loc. 218 S. D. S. N. H., Sulphur Canyon, east of South Mt., Ventura Co, (H, R. G.), Pleistocene: Lower San Pedro fauna at Deadman Island and San Pedro, rare; in upper San Pedro fauna at Crawfish George's, Los Cerritos (Signal Hill), San Pedro, and Deadman Island, Los .\ngeles Co.; Spanish Bight, San Diego, upper San Pedro fauna, (Arnold) ; lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd, as var, major) ; upper San Pedro fauna of Los Cerritos, (T, S, Old- royd); San Quintin Bay, Lower California, upper Pleistocene (E. K, Jordan); S. D, S. N, H, loc. 233, north of .\rroyo Santa Rosa, Ventura Co., lower Pleistocene, not rare (U. S. G.). Recent: .41aska to Gulf of California, Mexico (Dall). This species is readily recognized by the high spire and angulated periphery on the lower part of the body whorl. It resembles Mitrella borsoni Bellardi, of the Italian Mio- cene, to judge from Harmer's figure of that species in the Monograph of the Crag Mol- 698 San Diego Society of Natural History [ Memoirs lusca.i The northern cool-water specimens are larger than the southern ones, and Old- royd has separated the large forms as variety major. This name is preoccupied several times. Section Striomitrella, new section Type: Buccinum sulcatum J. Sowerby, Min. Conch. Gt. Brit., Vol. 4, p. 103, pi. 375, fig. 2, 1823; Vol. 5, p. 122, pi. 477, fig. 4, 1825; British Crag fossil (PUocene) ; figured also by Harmer, Mon. Palaio. Soc, Vol. 70, PUo. Moll. Gt. Brit., Vol. 1, pt. 3, p. 307, pi. 33, fig. 14, Feb., 1918; Nyst, Ann. Mus. Roy. Hist. Nat. Belg., Ser. Pal^o., Vol. 3, p. 36, pi. 3, fig. 2, 1881 (Scaldisien of Belgium). Entire exterior surface of shell with spiral sculpture. Mitrella sulcata (J. Sowerby), a spirally sculptured Pliocene and Pleistocene species of the Anglo-Belgian region of Europe, appears to be sufficiently distinct from those Mitrellas with the spiral sculpture confined to the basal portion of the body whorl to warrant sectional separation from Mitrella, s. s. Thesbia was proposed by Jeffreys- for a spirally striate group of C olumbella ; but the type, Thesbia nana (Loven), belongs to the Turridce, and hence Thesbia cannot be used here. The type of Striomitrella is an extinct species which occurs in the Pliocene and middle glacial sands of Great Britain and in the Scaldisien (upper Pliocene) of Belgium. Mitrella tenuilineata (Clark),' of the San Lorenzo Oligocene of Contra Costa County, California, belongs to this group. Clark's species has been poorly figured. It has a small, elongate shell with definite spiral sculpture over the entire surface. Genus STROMBINA Morch, 1852 Strombina Morch, Cat. Yoldi, p. 85, 1852; Pace, Proc. Malac. Soc. London, Vol. 5, no. 1, p. 43, April, 1902; list in- cludes S. lanceolata Sby. and S. gibberula Sby. Strombocolumhus Cossmann, Ess. Paleo. Conip., Vol. 4, p. 241, 1901; type, S. lanceolata Sowerby. Type (by subsequent designation, Cossmann, 1901), S. lanceolata Sowerby, 1832. Shell rather thick, elongate, with a high, sharp spire; apex acute; body whorl about half the length of the shell; whorls about eight, gibbous and nodulose; sutures slightly impressed; sculpture consisting of strong, protuberant, rounded nodes and very faint spiral threads on the basal portion of the body whorl; aperture narrow, elongate, sinuous; outer lip thickened externally and also in typical examples thickened internally in the middle, sometimes with faint teeth on the thickened part; inner lip reinforced by a callus deposit extending some distance from the aperture, but the polish on the callus ending sharply nearer the apertnre; anterior canal well formed, somewhat re- flected; posterior canal undeveloped. Average height of type, about 30 mm. Geologic range: Eocene (fide Cossmann, 1901) to Recent. Distribution: Warm seas of west American coasts. Strombocolumbus was proposed by Cossmann as a substitute for Stroinhina, under the misapprehension that Morch's name had been preoccupied by Bronn, who, however, used it for a group of genera^ and not as a part of a binomial name. The type of Strom- bocolumbus, S. lanceolata, Sowerby, being in the original list of species under Strombina, becomes the type of the latter genus. ' Mon. Palffio. Soc, Vol. 70, Plio. Moll. Gt. Brit.. Vol. 1, pi. 33, fig. 21. 1918. * Brit. Conch., Vol. 4, p. 359, 1867, monotype Tritonium ? nana Lov^n, Ind. Moll. Scand.. p. 12, 1846; type figured and described by Sara, Moll. Reg. Arct. Norv., p. 221, pi. 16. fig. 2, 1878: Forbes and Hanley, Hist. Brit. Moll., Vol. 3. p. 461. 1853; Vol. 4, pi. 112, fig. 8, 1853. "Univ. Calif. Publ. Geol., Vol. 11. p. 173, pi. 22, figs. 2, 3, 1918. * Fide Pace, Proc. Malac. Soc. London, Vol. 5, no. 1, p. 43, 1902. VoLDME I ] Pliocene and Pleistocene Mollusca of California 699 Strombina maculosa (Sowerby) Columbella maculosa Sowerby, Proc. Zool. Soc. London for 1832, p. 116; Reeve, Conch. Icon., Vol. 11, Cohimbella, pi. 4, sp. 19, figs. 19a, 19b, 1858; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 186, pi. 60, fig. 97, 1883; not of Pease, 1871. Slrambina maculosa Sowerby, Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Type specimen: In the British Museum. Type locality: Guacamayo, Central America. Pliocene: Carmen Island, Gulf of California, Mexico (Hanna & Hertlein, 1927). Recent: Cape San Lucas, Lower Calif ornifi, Mexico, to Central America; common in Gulf of California (A. M. Strong). This is the only reported Pliocene occurrence of Strombina on the Pacific coast of North America. Woodring^ reports several species of Strombina in the Caribbean Mio- cene, but states that the genus is now extinct in Atlantic waters. No species of Strombina has been reported in strata older than Pliocene on the Pacific coast of North America. Strombina gibberula (Sowerby) Columbella gibberula Sowerby, Proc. Zool. Soc. London for 1832, p. 115; Sowerby, Thes. Conch., Vol. 1, Columbella, sp. 76, p. 136, pi. 39, figs. 142, 143, 1844; Reeve, Conch. Icon., Vol. 11, Columbella, pi. 13, sp. 61, figs. 61a, 61b, 1858; Tryon, Man. Conch., Ser. 1, Vol. 5, p. 184, pi. 60, fig. 90, pi. 63, fig. 71, 1883; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 217, 1909. "Columbella gibbosula Broderip," d'Orbigny, Voy. Amer. Merid., Vol. 5, pt. 3, p. 430, 1841, .^de Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 282, 1909. Strombina gibberula Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 282, 1909. Type specimen: In the British Museum. Type locality: Unknown. Hab. "Bay of Caraccas and Puerto Portrero." Pleistocene: San Ignacio Lagoon, Lower California, Mexico (Oldroyd Coll. Stanford University, five speci- mens) . Recent: Lower California to Peru (A. M. Strong). This small species of Strombina is peculiar in having varix-Uke swellings on the body whorl caused by periodic thickening of the outer lip. The thickening on the exterior of the outer lip is prominent and there are two earlier thickenings on the body whorl, one on the left margin of the body whorl as viewed from the apertural side, and one on the back of the body whorl, the latter being like a nodosity on the shoulder of the whorl. The body whorl is large and shouldered, the sharp, narrow spire terminating in an acute apex. The largest fossil specimen in the Oldroyd Collection is 11 mm. in length. Strombina recurva (Sowerby) Plate 26, Figures 38, 41 Columbella recurva Sowerby, Proc. Zool. Soc. London for 1832, p. 115, 1832; Thes. Conch., Vol. 1, Columbella, p. 139, pi. 40, fig. 152, 1844; Reeve, Conch. Icon., Vol. 11, pi. 4, figs. 18a, 18b, 1858. Strombina recurva Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 219, 1909; Dall and Ochsner, Proc. Calif. Acad. Sci., Ser. 4, Vol. 17, p. 96, 1928. Shell of moderate size, high spired, with roimded axial nodes on upper part of body whorl, be- coming sharper on upper whorls; a few spiral threads on base of body whorl, outer lip greatly thick- ened, denticulate within; anterior canal notched. Dimensions: Height, 26 mm.; height of body whorl, about 15 mm.; diameter of body whorl, including thickened outer Up, 10 mm. 1 Carnegie Inst., Publ No. 385, pp. 282-5, 1928. 700 San Diego Society of Natural History [ Memoirs Type specivien: In the British Museum. Type locality: La Plata Island, Ecuador; Recent. ? Pleistocene: Old beach deposit north of Turtle Cove on Albemarle Island, Galapagos Islands (Dall and Ochsner; Stanford Collection). Recent: Central America to Guayaquil (Dall, 1909). This handsome species is strongly noded and has a gibbous body whorl. The base of the body whorl has a few revolving threads. S. gibberula is smaller and lacks the strong nodosities of this species. S. maculosa is smaller, has a less thickened outer lip, a less recurved anterior canal, and the sculpture is sonlewhat different. The Albemarle Island fossil bed described by Dall and Ochsner may be late Quatern- ary in age. The following species of Strombina occur in the Recent Pacific coast fauna south of San Diego, California, according to A. M. Strong: S. angularis Sowerby, 1832. Panama. S. colpoica Dall (subulata Sby., 1849, not Duclos, 1840). Gulf of California. S. dorsata Sowerby, 1832. Panama to Guayaquil. S. edenhila Dall. Gulf of California to Panama. S. elegans Sowerby, 1832. Central America. S. fusinoidea Dall (fusifonnis Hinds, 1844, not Anton, 1839, nor d'Orbigny, 1844). Central America. S. gibberula Sowerby, 1832. Lower California to Peru. .S. lanceolala Sowerby, 1832. Panama to Peru. S. Ulacina Dall. Gulf of California. , 1916. Pliocene: Lower Pliocene of Fresno County (Nomland). This species appears to have three prominent varices; and if it is a normal specimen, it may not belong to Eupleura, though Nomland's figure shows some characteristics of that genus. ■ Trans. Wagner Inst. Sci., Vol. l.p. 146. 1890; Proc. U. S. Nat. Mus., Vol. 14, p. 174, pi. 6. fig. .5, 1891, type locality, Mazatlan, Mexico. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 715 Genus THAIS Bolten, 1798 Thais Bolten, Mus. Boltenianum, p. 54, 1798; Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 46-50, 1909; Iredale, Trans. Proc. New Zealand Inst., Vol. 47, p. 472, 1915; Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 557, 1915; Stewart, Proc. Acad. Nat. Sci., Phila., Vol. 78, p. 386, and footnote, 1927; Woodring, Carnegie Inst., Publ. No. 385, 1928. Type (by subsequent designation, Iredale, 1915), Thais neritoides (Lamarck), =Murex fucus Gmelin, figured by Reeve, Conch. Icon., Vol. 3, Purpura, pi. 3, fig. 12, 1846; Cape Verde and Ascension Islands, Recent. Shell stout, spire low, aperture large, columella flattened, anterior canal very short; sculpture predominantly spiral, modified into scales, nodes or even spines, axial sculpture absent or of lamellar irregularities. The typical subgenus has not been reported from the later Cenozoic of California. It is characterized by a very large body whorl and aperture and an almost sunken spire. Although this subgenus looks very different from some species of Nucella, the group is very variable in characters and there are many intermediate species. Subgenus STRAMONITA Schumacher, 1817 Stramonita Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 226, 1817, two species included, one of which is Buc- cinum hxmasioma Chemnitz, Neues Syst. Conch. Cab., Vol. 11, p. 80, pi. 187, figs. 1796, 1797, dated 1795, Martini, Vol. 3, p. 274, pi. 101, fig. 966, 1777, other figures of Martini cited by Chemnitz excluded; Coss- mann. Ess. Pal^o. Comp., Vol. 5, p. 71, 1903; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 386, Jan. 3, 1927; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 295, 1928. Type (by subsequent designation, Cossmann, 1903), Buccinum hcemastoma Linnaeus, Syst. Nat., Ed. 12, p. 1202, 1767, figured as Purpura hceviastoma Linnseus by Reeve, Conch. Icon., Vol. 3, Purpura, pi. 5, species 21, August, 1846; Mediterranean. Shell like that of the typical subgenus but with higher spire, often with nodes or spines on the angle, a projection near the top of the inner lii3, said a small posterior canal. The two Neocene species, ponderosa and imperialis, are assigned to Stramonita ques- tionably. They lack the projection near the top of the inner lip and their posterior canals are not defined. They may belong more properly in the wilkesanus group of Chicoreus. Thais ? (Stramonita ?) imperialis (Dall) Not Purpura imperialis BlainviUe, Nouv. Ann. Mus. Nat. Hist. (Paris), Vol. I, pt. 2, p. 227, pi. 11, fig. 6, post May, 1832; Reeve, Conch. Icon., Vol. 3, Purpura, pi. 7, species 30, Aug., 1846. Not Murex (Phyllonotus) imperialis Swainson, 1833. Chrysodomus imperialis Dall, Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 353, 1908, manuscript name, nomen nudum; Dall, Prof. Paper 59 U. S. Geol. Surv., p. 42 (also pp. 17, 18), pi. 7, figs. 1, 3, ? pi. 18, fig. 1, 1909; Arnold, BuU. 396 U. S. Geol. Surv., p. 26, pi. 14, fig. 4, Jan. 15, 1910, figure reproduced in Bull. 398, pi. 36, fig. 4, 1910; Arnold and Hannibal, Proc. Amer. Pliilos. Soc, Vol. 52, pp. 590, 594, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 422, pi. 68, fig. 2, 1915; Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 32, 1916; Nom- land, Univ. Cahf. Publ. Geol., Vol. 9, p. 203, 1916; Vol. 10, p. 220, 1917; Howe, Vol. 14, p. 93, 1922; ? Dick- erson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 550, 1922; Dall, Amer. Journ. Sci., Ser. 5, Vol. 4, p. 313, 1922. Neplunea maxfieldi Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 219, pi. 6, fig. 54, Nov. 24, 1909, fide Dall, 1922. Type specimens: Of both imperialis and maxfieldi, in the U. S. National Museum. v. Miocene: Empire formation of Coos Bay, Oregon (Dall; Arnold and Hannibal; Howe); sea cliffs near Tahola, Washington (Arnold and Hannibal); Montesano of Washington (Weaver); Quillayute formation (Reagan), redeposited Empire; upper San Pablo, Sculella hreu'criana zone (Clark). Pliocene: Jacalitos formation on Canoas Creek, etc., Coalinga district (Arnold) ; rare in the Chione elsmerensis zone (Nomland); ? Purisima formation, Pescadero Creek near the mouth of Jones Gulch and on the Halliday Ranch, Santa Cruz Mts. (Arnold, 1908) ; 7 Merced formation a half mile north of Free- stone, Sonoma County (Dickerson). 716 San Diego Society of Natural History [Memoirs The difficulty with this species is that it was described from a badly worn specimen that does not show the sculpture nor the apertural characters. The species has been assigned to Chrysodomus because it resembles somewhat Neptunea (formerly called Chrysodomus) satura (Martyn). However, it is a rather peculiar form for Neptunea and the strong partitions across the suture suggest that it is more likely to belong to some genus like Thais. The specimen from the Purisima figured by Dall may not be the same species. Its form suggests Ranella pacifica (Dall). On the other hand, the figure given by Arnold (1910) seems to be of this species and is of a better preserved specimen, though the aperture is not showing. It resembles Clark's figure of Thais ponderosa variety diabloensis.^ Stewart has recently shown that ponderosa- is probably more closely related to Thais than it is to Forreria, the genus recently separated off from Trophon that now contains the group of species with which ponderosa was formerly classed. It is not unlikely that imperialis is related to ponderosa. It must be admitted that these two species resemble some Miocene forms of Forreria, even that Arnold's figure has the shape of Trophon geversianus, the type of Trophon, though the shell is larger and much heavier. Thais, Forreria, and Trophon may intergrade in the early Miocene. The species ponderosa and imperialis differ from Forreria in lacking the angulation on the lower part of the body whorl and in having a shorter anterior canal. A specimen of Thais in the collection at the California Institute of Technology from the San Pablo formation resembles Clark's figure of imperialis. A specimen in the collection at Stanford University collected by Harold Hannibal from the Empire formation at the mouth of Maxfield Creek, Mora, Washington, has all the earmarks of Thais. As Purpura imperialis Blainville has the apertural characters of Stramonita, though the shell seems to be smaller and thinner, with more spinose nodes, it may be necessary to use Reagan's name maxfieldi. Even should this species be transferred to the wilkesanus group, the name would be preoccupied by Chicoreus (Phyllonotus) imperialis (Swainson). Subgenus NUCELLA Bolten, 1798 Nucdla Bolten, Mus. Boltenianum, p. 54, 1798; Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 48, 50, 1909; Dall, Proc. U. S. Nat. Mus., Vol. 49, pp. 557-563, 1915; Stewart, Proc. Acad. Nat. Sci. PhHa., Vol. 78, p. 386, 1927. Type (by subsequent designation, Dall, 1909), Nucella lapillus Linnaeus, figured by Reeve, Conch. Icon., Vol. 3, Purpura, pi. 10, figs. 47a, 476, 1846; coasts of Europe. Shell usually with a higher spire than typical Thais, and with spiral and axial sculpture both present, the latter sometimes well developed, or with both spiral and axial sculpture obsolete or nearly so. Typical Thais has an anal notch in the aperture which is entirely lacking in Nucella. Dall (1915) has given a detailed description of Nucella. Thais (Nucella) lamellosa (Gmelin) Plate 32, Figures 14, 26 Bucdnum plicalum Martyn, Univ. Conch., Vol. 2, pi. 44, 1788, not B. plicatum Linnaius, 1758. Buccinum cmnposilum Chemnitz, Conch. Cab., Vol. 10, p. 179, Vign. 21, figs, a, b, 1788, not strictly binomial. Bucdnum lamdlosum Gmelin, Syst. Nat., Ed. 13, p. 3498, 1790; Bolten, Mus. Boltenianum, Ed. 1, p. 113, 1798. Bucdnum crispatum Chemnitz, op. dt., Vol. 11, pp. 70, 84, pi. 187, figs. 1802, 1803, 1795, binomial ? 1 Trophon ponderosum Gabb variety pabloensis Clark (in text), didbloensis (iuexpl. of plate), Univ. Calif. Publ. Geol., Vol. 8, p. 500. pi. 66, fig. 5, 1915. ' Trophon ponderosum. Gabb, Geol. Surv. Calif., Palajo., Vol. 2, p. 2, pi. 1. fig. 3, 1866; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 499, pi. 66, figs. 3, 4, 1915; Thais (Slramonila) ponderosa (Gabb), Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 385, pi. 31, fig. 3. Jan. 3, 1927. Clark's figure 3 shows the type, which looks leas like Stramonita than the specimen figured by Stewart. Clark's figures show that the anterior canals have somewhat the form of the anterior canal of the wilkesanus group. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 717 Polyplex rugosus Perry, Conch., pi. 9, fig. 2, 1811. Murex crispatus Lamarck, Hist. Anim. s. Vert., Vol. 7, p. 174, 1822. Mtmx ferrugineus Eschscholtz, Zool. Atlas, Pt. 1, p. 10, pi. 9, figs. 2A, 2B, 1829. Murex lacluca Eschscholtz, op. cit., p. 11, pi. 9, figs. 3A, 3B, 1829, not of Bolten, ^ide Dall, 1915. Polylropa crispata Lamarck, Swainson, Treat. Malac, p. 30.5, 1840. Purpura septenlrionalis Reeve, Conch. Icon., Vol. 3, Purpura, pi. 10, fig. 50, 1846. Purpura (Polylropa) crispata Chemnitz, Tryon, Man. Conch., Ser. 1, Vol. 2, p. 175, pi. 53, fig. 1(50, pi. 54, figs. 163-166, 168, 1880. Purpura crispata Chemnitz, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 261, 18S8; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 261, 1903; ? Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 121, pi. 6, fig. 57, 1909. Thais (Nucella) lamellosa Gmelin, DaU, U. S. Geol. Surv., Prof. Paper 59, p. 50, 1909; Proc. U. S. Nat. Mus., Vol. 49, p. 563, pi. 74, figs. 5, 6, 7, 8, 1915; U. S. Nat. Mus., Bull. 112, p. Ill, 1921; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 42, pi. 38, figs. 1, 2, 4, pi. 35, fig. 7, 1927. Thais plicala Martjm, Vanatta, Nautilus, Vol. 24, p. 37, 1910. Thais crispata Chemnitz, Arnold, U. S. Geol. Surv., Bull. 396, p. 128, pi. 11, fig. 4, January 15, 1910; Bull. 398, pi. 33, fig. 4, 1910. Thais etchegoinensis Arnold, U. S. Geol. Surv., Bull. 396, p. 142, pi. 18, fig. 2, January 15, 1910; Bull. 398, pi. 40, fig. 2, 1910. Thais lamellosa Gmelin, Thompson, Rept. British Columbia Comm. Fisheries for 1912, p. 1-42, pi. 9 (shell), pi. 10 (egg capsules), 1913; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 221, 1917. Thais lamellosa, var. franciscana DaU, Proc. U. S. Nat. Mus., Vol. 49, p. 565, 1915; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 43, pi. 35, fig. 6, 1927. Thais lamellosa, var. hormica Dall, op. cit., p. 565, 1915; I. S. Oldroyd, op. cit., p. 43, pi. 38, figs. 3, 5, pi. 35, fig. 8, 1927. Thais lamellosa, var. nepiunea Dall, op. cit., p. 565, 1915; I. S. Oldroyd, op. cit., p. 43, 1927. Thais lamellosa, var. cymica Dall, op. cit., p. 565, 1915; L S. Oldroyd, op. cit., p. 43, pi. 35, fig. 5, 1927. Thais lamellosa, var. sitkana Dall, op. cit., p. 566, 1915; L S. Oldroyd, op. cit., p. 44, 1927. Thais (Nucella) nomeana DaU, U. S. Geol. Surv., Prof. Paper 125-C, p. 29, pi. 5, fig. 9, 1920. Thais (Nucella) shumanensis Carson, BuU. So. Calif. Acad. Sci., Vol. 25, p. 56, pi. 3, figs. 1, 2, 1926. Miocene: Upper Miocene (Arnold, U. S. Geol. Surv., Bull. 396, p. 128, 1910). Pliocene: Coos conglomerate of Coos Bay, Oregon; upper WUdcat of northern California; Merced and Purisima formations of middle California; Jacalitos and Etchegoin formations of San Joaquin basin; Pico formation near Ventura; Pacific Beach and Balboa Park Pliocene, San Diego (see references to California authors given above) ; etc. Pleistocene: Santa Barbara to San Diego (Cooper); "Saugus" near Ventura (WaterfaU); upper San Pedro series of San Pedro, Deadman Island, and Crawfish George's, Los Angeles County, "not common" (Arnold, 1903); etc. Recent: Port Clarence, Bering Strait, to Aleutian Islands and south to Santa Barbara, California; also to Sado Island, Japan Sea (DaU, 1921). This excessively variable species has been thoroughly overnamed. In the Oldroyd Collection at Stanford University there is a series of specimens showing all intermediate steps from smooth forms to those with strong axial frills and from small, low-spired in- dividuals to large, high-spired individuals. This species affords a classic example of in- dividual variation. The varietal names proposed by Dall (1915) have absolutely no systematic value. Thais (Nucella) lima (Martyn) Plate 32, Figure 15 Buccinum lima Martyn, Univ. Conch., Vol. 2, i)l. 46, 178S. Purpura saxicola Valenciennes, Voy. Venus, Atlas, p. 4, pi. 8, figs. 4, 4a, 1846; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 262, 1888; Keep, West Coast SheUs, p. 31, fig. 11, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 261, 1903. Purpura attenuata Reeve, Conch. Icon., Vol. 3, Purpura, pi. 10, fig. 49, 1846. Purpura frcycinetii Deshayes, Middendorff, Siber. Reise, Vol. 2, p. 219, pi. 12, figs. 5-9, 1851, in part, not of Deshayes, 1839. Purpura (Polylropa) saxicola Valenciennes, Tryon, Man. Conch., Ser. 1, Vol. 2, p. 174, pi. 53, figs. 152-1547, 1880. Purpura lima Martyn, Anderson, Proc. Calif. Acad. Sci., Ser. 3 (Geol.), Vol. 2, p. 202, pi. 15, figs. 62, 63, 1905. 718 San Diego Society of Natural History [Memoirs Thais lima Martin, Keep, West Amer. Shells, p. 180, fig. 169, 1911; Clark Univ. Calif. Publ. Geol., Vol. 8, p. 423, 1915. Thais (Nucella) lima Martyn, Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 566, pi. 75, figs. 4, 5, 6, 1915; U. S. Nat. Mus., Bull. 112, p. 112, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 44, pi. 36, figs. 4, 5, 6, 1927. Miocene: Middle Miocene of Kern River district (Anderson); upper and lower San Pablo formations, upper Miocene of middle California (Clark); Kirker's Pass, Mount Diablo region (Cooper). Pliocene: Santa Rosa; San Fernando, Los Angeles County (Cooper). Pleistocene: Pleistocene near Ventura; Santa Barbara; rare in upper San Pedro series at San Pedro (Arnold). Recent: Arctic Ocean to Cedros Island, Lower California, Mexico; also to northern Japan (Dall, 1921). This variable species has been in some confusion. It is likely that the above synony- mv will need revision when the Pacific coast Nucellas are better known. Thais (Nucella) emarginata (Deshayes) ? Piirjmra lagenaria Duclos, Ann. Sci. Nat., Vol. 26, p. 112, pi. 2, fig. 11, May, 1832, not of Lamarck, 19,22, fide Dall, 1915. Purpura emarginata Deshayes, Rev. Zool. Soc. Cuv., p. 360, 1839; Guerin's Mag. Zool., pi. 25, 1841; Reeve, Conch. Icon., Vol. 3, Purpura, pi. 10, fig. 46, 1846; Cook, Proc. Malac. Soc. London, Vol. 11, p. 203, 1915. ? Purpura rupestris Valenciennes, Voy. Venus, Atlas, pi. 9, figs, lo, l^, 1846, fide Dall, 1915. Thais emarginata Deshayes, Vanatta, Nautilus, Vol. 24, p. 37, 1910 (but not his synonymy). Thais (Nucella) emarginata Deshayes, Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 569, pi. 75, figs. 1, 2, 3, 1916; U. S. Nat. Mus., Bull. 112, p. 112, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 44, pi. 36, figs. 2, 3, 1927. Pliocene: (See discussion below). Recent: Bering Sea to Mazatlan and Topolobampo, Mexico. It is quite probable that some of the records of fossil occurrence which have been assigned to lima in this catalogue should be included under emarginata. Until these variable species can be studied from abundant material (to measure the extent of indi- vidual variation) and the biologic units compared with original descriptions and figures, no useful contribution to our knowledge of them can be made. Species of Nucella which have been reported only from the Pleistocene of Lower Cali- fornia, Mexico, have not been included here. Thais (Nucella) canaliculata (Duclos) Purpura canaliculata Duclos, Ann. Sci. Nat., Vol. 26, p. 104, pi. 1, fig. 1, May, 1832. Thais (Nucella) precursor Dall, U. S. Geol. Surv., Prof. Paper 59, p. 51, pi. 4, fig. 4, 1909. Thais (Nucella) canalindata Duclos, Dall, Proc. U. S. Nat. Mus., Vol. 49, p. 567, pi. 74, figs. 1-4, 1915; U. S. Nat. Mus., Bull. 112, p. 112, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 46, pi. 35, figs. 3, 4, 1927. Pleistocene: Fossil Rock, Coos Bay, Oregon (Dall, as precursor). Recent: Aleutian Islands to Monterey, California (Dall, 1921). Thais (Nucella) collomi Carson Thais (Nucella) collomi Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 57, pi. 4, figs. 1, 2, 1926. Type specimen: In the collection at Stanford University, No. 111. Type locality: Half mile north of Schuman, in Southern Pacific R. R. cut, Santa Maria district, Santa Barbara County, Pliocene. Pliocene: At the type locality (Carson). This is a very large species with scaly sculpture. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 719 Thais (Nucella) elsmerensis, new species Plate 32, Figure 13 Shell of small or moderate size, ovate, spire rather low and conical, body whorl large, aperture of moderate size, rather narrow, pillar nearly straight, the parietal wall with a callus wash; axial sculpture absent, spiral sculpture consisting of low, fine spiral cords, which are paired over part of the body whorl. Height 32 mm., width of body whorl 19 mm. Type specimen: No. 299 in the collection of the San Diego Society of Natural History. Type locality: S. D. S. N. H. locality 216, basal Pliocene east of Fernando Pass, Los Angeles County. Pliocene: At the type locality; also from the basal Pliocene of Elsmere Canyon, Los Angeles County (H. R. G.). The distinctive features of this shell are the wide, nearly straight pillar, the relatively narrow aperture, and the very low, fine spiral sculpture. Thais emarginala has low, but very much larger spirals or may be nearly smooth. Also, its columella is not so straight. Thais canaliculata usually has much more strongly developed spiral sculpture; but this feature appears to be very variable, and a few specimens have subdued spirals nearly like those of elsmerensis. However, els7nerensis can be distinguished even from such specimens of canaliculata, as it can from all other named California species, by its straighter columella, which means that the body whorl is less constricted toward the base. In time it may be found that elsmerensis should be considered a variety of one of the older, very variable species. Genus ACANTHINA Fischer de Waldheim, 1807 Acanthina Fischer de Waldheim, Mus. Demidoff, Vol. 3, p. 174, 1807. "Acanlhiza Fischer," Gray, Free. Zool. Soc. London for 1847, p. 138, 1847. Type (by subsequent designation,' Gray, 1847), Buccinum monoceros Chemnitz, Conch. Cab., Vol. 10, p. 197, pi. 154, figures 1469, 1470, 1788; = Buccinum calcar Mar- tyn, Univ. Conch., Vol. 1, fig. 10 and explanatory table, 1784; southern west coast of South America, Recent. Shell short, with small spire, large body whorl, and very short anterior canal; spiral sculpture usuall.y present but varices and axial sculpture absent; aperture ovate, parietal wall usually with a delimited callus deposit, a projecting tooth present at some growth stages on anterior portion of outer lip. Acanthina lugubris (Sowerby) Monoceros lugiihre Sowerby, Genera of Shells, Monoceros, fig. 3, 1821 ; Conch. lUust., fig. 11, 1835; Tryon, Man. Conch., Ser. 1, Vol. 2, p. 193, pi. 60, fig. 291, 1880; Baker, Xautilus, Vol. 16, p. 40, 1912. Acanthina lugubris Sowerby, Cooke, Proc. Malac. Soc. London, Vol. 13, p. 9, text fig. 7 (radula), also p. 10, 1918; Strong, Nautilus, Vol. 38, p. 22, 1924; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924, Acanthina (Acanthina) lugubris Sowerby, Dall, U. S. Nat. Mus., Bull. 112, p. 113, 1921; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 48, 1927. Type locality: California, Recent. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: San Diego, California, to Magdalena Bay, Lower California, Mexico, and the Galapagos Islands (DaU). This species has a strong anterior tooth projecting from the outer lip, a feature characteristic of Acanthina but not always developed. ' The original description of Acanthina Fischer de Waldheim not being available, Gray's designation of type has been accepted tentatively without testing its validity, ""Acanthiza Fischer" of Gray appears to be a pure error in spelling for Acanthina. 720 San Diego Society of Natural History [Memoirs Section Acanthinucella Cooke, 1918 Acanthinucella Cooke, Proc. Malac. Soc. London, Vol. 13, p. 7, Sept. 9, 1918. Type (by original designation), Acanthina punctulata Sowerby. Acanthina spirata (Blainville) Plate 32, Figures 6, 7, 8 Purpura spirata Blainville, Nouv. Ann. Mus. Paris, Vol. 1, p. 252, pi. 12, fig. 8, 1832. Purpura engonata Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 264, pi. 20, fig. 17, 1837. Monoceros engonalum Conrad, Tryon, Man. Conch., Ser. 1, Vol. 2, p. 195, pi. 61, fig. 304, 1880; Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 251, 1888; Keep, West Coast SheUs, p. 29, fig. 10, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 246, 1903. Acanthina (Acanlhinucella) spirata Blainville, Dall, U. S. Nat. Mus., Bull. 112, p. 112, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 47, 1927. Acanthina spirata Blainville, Strong, Nautilus, Vol. 38, p. 23, 1924. Acanthina {Acanthinucalla) spirata Blainville, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type specimen: In the Paris Museum. Type locality: "Des lies Sandwich" (an error presumably or based on a ballast shell). Pleistocene: Barlow's Ranch, near Ventura (Arnold) ; "Saugus" formation near Ventura (Waterfall) ; S. D. S. N. H. locality 244, Las Posas zone, lower Pleistocene in Sexton Canyon, Ventura County; Lake Merced, San Mateo County, and all the lower and upper San Pedro series localities in the San Pedro district (Arnold) ; S. D. S. N. H. locality 78, upper Pleistocene terrace near Seacliff station, about eight miles northwest of Ventura. Recent: Puget Sound to San Diego, California, and Socorro Island, Lower California, Mexico (Dall, 1921). The typical variety of spirata has been confused with varieties punctulata and uni- carinata. It is possible that the California Pleistocene shell referred to above should be called Acanthina spirata var. unicarinata (Sowerby).^ Acanthina spirata (Blainville) variety punctulata (Sowerby) Monoceros punctulatum Sowerby, Conch. Illust., Monoceros, fig. 3, 1835. Monoceros lapilloides Conrad, Journ. Acad. Nat. Sci. Phila., Vol. 7, p. 265, pi. 20, fig. 18, 1837; Tryon, Man. Conch., Ser. 1, Vol. 2, p. 195, pi. 61, fig. 305, 1880; Keep, West Coast SheUs, p. 28, fig. 9, 1888, 1892; Cooper, Calif. State Mining Bureau, Bull. No. 4, Pt. 3, p. 28, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 247, 1903. Acanthinucella punctulata (Sowerby), Cooke, Proc. Malac. Soc. London, Vol. 13, pp. 8, 10, text fig. 3, p. 9 (radula), 1918. Acanthina lapilloides Carpenter, E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919. Acanthina (Acanthinucella) spirata punctulata Sowerby, Dall, U. S. Nat. Mus., BuU. 112, p. 113, 1921. Acanthina spirata var. punctulata Sowerby, Strong, Nautilus, Vol. 38, p. 21, 1924. Pleistocene: Ventura County (Cooper) ; "rare in upper San Pedro series of San Pedro; one specimen" (Arnold) ; chiton bed on Point Firmin, near San Pedro (Chace). Recent: Monterey, California, to San Thomas, Lower California, and Socorro Island, Mexico (Dall, 1921). Genus TROPHON Montfort, 1810 Trophon Montfort, Conchyl. Syst., Vol. 2, p. 483, 1810. Type (by original designation), Trophon magellanicus (Gmelin), = Buccinum geversianum Pallas, figured by Reeve, Conch. Icon., Vol. 4, Fusus, pi. 4, fig. 2, 1847, by H. and A. Adams, Gen. Rec. Moll., Vol. 3, pi. 8, fig. 3c, 1855, by Sowerby, Thes. Conch., Vol. 4, Trophon, p. 59, pi. 2, figs. 7, 8, 1880, and by Tryon, Man. Conch., Ser. 1, Vol. 2, p. 144, pi. 32, fig. 339, 1880; Straits of Magellan to Chile, Recent. » strong, Nautilus, Vol. 38, pp. 18, 104, 1924. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 721 Shell fusiform, sometimes stout, with oval or roimd aperture, more or less long, somewhat bent, open anterior canal, and axial and in most cases spiral sculpture. The type of the genus Trophon is a rather stout shell with large body whorl and nearly round aperture, a moderately long, somewhat bent anterior canal and partially open umbilicus. It has numerous but distant, lamellar, varix-like axial ribs, which are pointed on the shoulder of the whorls. "Trophon" ponderosum Gabb, of the California Miocene, is a Thais. Subgenus BOREOTROPHON Fischer, 1884 Boreolrophmi Fischer, Man. de Conchyl., p. 640, 1884. Type (by monotypy), Trophon clathratus (Linnaeus), figured by Tryon, Man. Conch., Ser. 1, Vol. 2, p. 140, pi. 31, fig. 312, 1880, northern coasts of Europe. Shell somewhat fusiform, with long, slender anterior canal, axial ribs not developed into promi- nent lamellae and without long spines on the shoulder of the whorls; spiral sculpture absent or faiat. Boreotrophon Fischer takes the place of "Neptunea Bolten," as erroneously used by Ball. The follow^ing is an alphabetical list of species of Boreotrophon which have been reported from the Pliocene and Pleistocene formations of California and of some other locaUties in western North America. Trophon (Boreotrophon) beringi (Dall) Boreotrophon beringi Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 544, March 31, 1902. Neptunea beringi Dall, Canadian Arctic E.xpedition, Vol. 8, Pt. A, p. 26A, 1919. Trophon {Neptunea) beringi Dall, U. S. Nat. Mus., Bull. 112, p. 109, pi. 10, fig. 6, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 33, pi. 30, fig. 6, also Pt. 1, pi. 18, fig. 8, 1927. Type specimen: In the U. S. National Museum, No. 109,051. Type locality: Bering Sea. Pleistocene: South side of Herschel Island, Yukon Territory (Dall, 1919). Recent: Icy Cape, Arctic Ocean, to Puget Sound; Japan (Dall, 1921). This species is very similar to clathratus, the type of the subgenus Boreotrophon Fischer. Trophon (? Boreotrophon) cerritensis Arnold Trophon {Boreotrophon) cerritensis Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 249, pi. 6, fig. 6, 1903. Neptunea cerritensis Arnold, Dall, U. S. Nat. Mus., Bull. 112, p. Ill, 1921. Type specimen: In the U. S. National Museum, No. 162,545. Type locality: Deadman Island, off San Pedro, Los Angeles County, Pleistocene. Pleistocene: Lower San Pedro series at Deadman Island, one adult and five juvenile specimens; also one from Los Cerritos; both Los Angeles County (Arnold). This is a large species, well figured by Arnold. Dall (1921) classified it in the section Trophonopsis ; but although the specimen figured by Arnold appears to be much worn, its characters suggest a relationship with the orpheus and stuarti group rather than with Trophonopsis. 722 San Diego Society of Natural History (Memoirs Trophon (Boreotrophon) fleenerensis (Martin) Boreotrophoji fleenerensis Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 191, pi. 22, figs. 3a, 3b, .3f, August 6, 191-1. Type specimen: In the collection at the University of California. Type locality : Two miles south of Centerville, Humboldt County, California, Plio- cene. Pliocene: Two miles south of Centerville, Humboldt County, abundant in upper portion of the Wildcat series (Martin). Trophon (Boreotrophon) multicostatus (Eschscholtz) Murex nndlicoslatvs Eschscholtz, Zool. Atlas, Pt. 2, p. 11, pi. 4, fig. 4, 1829. f "Trophon gunneri Loven," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 663, 1864, not of Loven, 1846. ? "Boreotrophon gracilis Perry," Berry, Nautilus, Vol. 22, p. 38, 1908, not of Perry. ? "Trophon gracilis Perry," Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 221, 1917; and of other Pacific coast authors, not of Perry, 1801. Neptunea muUicostata Eschscholtz, Dall, U. S. Nat. Mus., Bull. 112, p. 110, pi. 13, fig. 1, 1921. Trophon {Neptunea) multicostatus Eschscholtz, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 33, pi. 33, fig. 11, 1927. Trophon (Neptunea) muUicostata Eschscholtz, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type locality: Sitka, Alaska, Recent. Pliocene: Pecten coalingensis zone, middle Etchegoin of Coalinga region (Nomland); Bath-house Beach, uppermost Pliocene, Santa Barbara (Arnold; Berry). Pleistocene: "Pliocene" and lower San Pedro series of Deadman Island, Los Angeles County, "rare" (Arnold); "Saugus" formation near Ventura (Waterfall). Recent: Nunivak Island, Bering Sea, to San Pedro, California; also northern Japan (Dall, 1921). Arnold's figure of multicostatus is really Trophon (Boreotrophon) pacificus (Dall). Trophon (Boreotrophon) orpheus (Gould) Plate 32, Figure 9 Fusus orpheus Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 142, 1849; U. S. Explor. Exped., Vol. 12, p. 234, 1852, Atlas, pi. 16, figs. 285, 285n, 2856, 1856. Trophon orpheus Gould, Crosse, Journ. de Conchyl., Vol. 2.5, p. 103, 1877; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 268, 1888; Newcombe, Bull. Nat. Hist. Soc. Brit. Columbia, p. 70, 1893. Boreotrophon orpheus Gould, Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 542, 1902. Trophon (Neptmiea) orpheus Gould, DaU, U. S. Nat. Mus,, Bull. 112, p. 110, pi. 6, fig. 7, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 37, pi. 30, fig. 14, 1927. Type specimen: In the collection of the Boston Society of Natural History or in the U. S. National Museum ? Type locality: Puget Sound, Recent. Pliocene: San Diego well, middle Pliocene, San Diego (Cooper); S. D. S. N. H. locality 218, upper Pliocene (Santa Barbara zone) of Sulphur Canyon east of South Mountain, Ventura County (H. R. G.). Pleistocene: San Pedro; San Diego (Cooper, probably including Arnold's variety precursor). Recent: Victoria, British Columbia, and off the Colimibia River, Oregon (Dall, 1921). Trophon [Boreotrophon) orpheus (Gould) has sometimes been confused with T. (B.) stuarti (Smith), which is a larger species with fewer but more accentuated, sub-lamellar axial ribs. The recent figure of orpheus given by Dall (and reproduced by Oldroyd, who figures both species) will assist in distinguishing the two. Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 723 Trophon (Boreotrophon) orpheus (Gould) variety pedroanus Arnold Trophon (Boreotrophon) pedroana Arnold, Mem. Calif. Acad. Sci., Vol. .3, p. 251, pi. 6, fig. 12, 1903. Nepiunea pedroana Arnold, Dall, U. S. Nat. Mus., Bull. 112, p. Ill, 1921. Type specimen: In the U. S. National Museum. Type locality: Deadman Island, Los Angeles County, lower Pleistocene. Pleistocene: Lower San Pedro series at San Pedro and Deadman Island, "rather common"; upper San Pedro series at Crawfish George's, Los Angeles County (Arnold). The shell of this species is like that of an eroded orpheus, but the whorls are more evenly rounded and there are but three widely spaced spiral ribs. Arnold's variety proecursor (of orpheus) may be a synonjan. It is probable that pedroanus itself is only a variant of orpheus. In any case it is evident that the species of this group need revision so that the unnecessary names can be eliminated. Trophon (Boreotrophon) orpheus (Gould) variety praecursor Arnold Trophon (Boreotrophon) stuarti Smith, var. precursor Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 253, pi. 6, fig. 5, 1903. Type specimen: In the U. S. National Museum, No. 162,546. Type locality: Deadman Island, Los Angeles County, Timms Point zone, lower Pleistocene. Pliocene: Bath-house Beach, Santa Barbara, uppermost Pliocene (Arnold). Pleistocene: "Not uncommon" in the "Pliocene" and [he lower San Pedro .series of Deadman Island, Los Angeles County (Arnold). This very close variety is more slender and has less sharply defined sculpture (eroded ?) than typical orpheus. It also resembles pedroanus. Trophon (Boreotrophon) pacificus (Dall) "Trophon multicostatus Eschscholtz" of some California conchologists, in part, not of Eschsoholtz. Boreotrophon pacificus Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 544, March 31, 1902. "Trophon (Boreotrophon) multicostalns Eschscholtz," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 251, pi. 6, fig. 9, 1903. "Trophon (Boreotrophon) scalariformis Gould," Arnold, op. cit., p. 252, pi. 6, fig. 10, 1903, noo of Gould. Neptunea pacifica Dall, U. S. Nat. Mus., Bull. 112, p. 110, pi. 11, fig. 5, 1921. Trophon (Neptunea) pacificus Dall, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 35, pi. 30, fig. 4, 1927. Type specimen: In the U. S. National Museum, No. 109,100. Type locality: Bering Sea ? Pleistocene: "Pliocene" of Deadman Island, lower and upper San Pedro series of San Pedro region (Arnold). Recent: "Arctic Ocean southward, on the west to Kamchatka and on the east in deep water to Acapulco, Mexico." (DaU, 1921.) Arnold's figures of both multicostatus and scalariformis. probably represent this species. Trophon (? Boreotrophon) perelegans Nomland Trophon perelegans Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 311, pi. 20, figs. 1, 2, 3, November 8, 1917. Type specimen: In the collection of the California Academy of Sciences, No. 11,321. Type locality: About eleven miles northeast of Coalinga, Fresno County, upper Miocene. Miocene: At the type locality, Santa Margarita formation northeast of Coalinga; Nacimiento River, eight miles west of San Miguel, San Luis Obispo County; Vineyard Creek anticline, Monterey County (Nomland). This species has some of the aspects of a small Forreria. 724 San Diego Society of Natural History [ Memoirs Trophon (Boreotrophon) raymondi Moody Tropho7i raymondi Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 53, pi. 1, figs, la, 16, October 11, 1916. T]jj)e specimen : In the collection at the University of California, No. 11,088. Type locality : Fourth and Broadway, Los Angeles, Pliocene. Pliocene: Lower part of the upper Pliocene at the type locality (Moody); also from the same horizon at Fifth and Hope streets, Los Angeles (coll. by Charles M. Jay). This form is very similar to and is probably the precursor of Trophon {Boreotrophon) eucymatus Dall,' from which it differs in having a lower spire and less gracefully tapering body whorl. T. raymondi has a more cubic appearance because of its lower spire and the constriction or abrupt tapering of the lower portion of the body whorl. Trophon bentleyi Dall- is also similar; but it has a longer anterior canal than either of the others, and the varices project upward to form a more pronounced spinose coronation on the tabulation of the body whorl. How much importance these characters have for specific distinctions can be determined only by a study of a large series of specimens. Trophon (Boreotrophon) stuarti Smith Trophon stuarti E. A. Smith, Proc. Zool. Soc. London for 1880, p. 481, pi. 48, fig. 6, 1880. Boreolropho7i {stuarti var. ?) smithi DaU, Proc. U. S. Nat. Mus., Vol. 24, p. 542, 1902. "Trophon {Boreotrophon) gracilis Perry," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 250, pi. G, fig. 8, 1903, not Polyplex gracilis Perry, Conch., pi. 9, fig. 4, 1801. Trophon {Boreotrophon) stuarti Smith, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 252, pi. 6, fig. 4, 1903; U. S. Geol. Surv., BuU. 396, p. 156, pi. 25, fig. 2, January 15, 1910; BuU. 398, pi. 47, fig. 2, 1910. Boreotrophon stuarti Smith, Berry, Nautilus, Vol. 22, p. 38, 1908. Trophon {Neptunea) stuarti Smith, Dall, U. S. Nat. Mus., Bull. 112, p. Ill, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 38, pi. 33, fig. 13, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Trophon {Neptunea) smithi Dall, U. S. Nat. Mus., Bull. 112, p. Ill, pi. 13, fig. 8, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 38, pi. 33, fig. 14, 1927. Type locality: Vancouver Island, British Columbia, Recent. Pliocene: Etchegoin formation of Coalinga region (Arnold, 1910); Bath-house Beach, Santa Barbara, upper Pliocene (Berry); San Diego well (Arnold, 1903). Pleistocene: "Pliocene" of Deadman Island and Timm's Point and lower San Pedro of Deadman Island, Los Angeles County (Arnold, 1903). Recent: Shumagin Islands, Alaska, to San Diego, California. Polyplex gracilis Perry, as figured by that author, has about twice as many axial ribs as the specimen figured by Arnold. Perry gave the habitat of gracilis as "New Zealand." Trophon (? Boreotrophon) triangulatus Carpenter Trophon triangulatus Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 663, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 224, February, 1866; Tryon, Man. Conch., Ser. 1, Vol. 2, p. 142, 1882; ? Cooper, 7th Ann. Rept. Calif. State Mmeralogist, p. 268, 1888; Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 180, in part, pi. 5, fig. 3 only, 1891. ? Trophon {Boreotrophon) triangulatus Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 254, in part, 1903. Trophon {Austrotrophon) triangulatus Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 109, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 28, pi. 34, figs. 6, 7, 1927. Type specimen: In the State Collection, No. 580a, University of California. Type locality: Off Catalina Island, California. ' Proc. U. S. Nat. Mus.. Vol. 24, p. 547, 1902, type locality 124 fathoms oS San Diego; figured in Bull. 112, U. S. Nat. Mus., pi. 15, fig. 7 1921. ' Proc. U. S. Nat. Mus.. Vol. 34, p. 249. 1908, type locality, off San Diego harbor, in 20 fathoms, mud. Trophon tripherus Dall, as figured (U. S. Nat. Mus., Bull. 112, p. Ill, pi. 1.5. figs. S, 9, 1921) is also similar, but we have not seen specimens. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 725 Pleistocene: Santa Barbara (Cooper) ; lower San Pedro series of Deadman Island, Los Angeles County, "rare" (Arnold) . Recent: Catalina Island and San Pedro, California (Dall, 1921). This is a small species, the type, which is figured by Dall (1891) and by Oldroyd (1927), being about 10 mm. long. It has been confused with the species now known as Forreria catalinensis (Oldroyd) ; but it is very much smaller, is clearly not the young of that species, and may not even be related to Austrotrophon. It may be an early name for some species of Boreotrophon now known by a later name. Subgenus TROPHONOPSIS Bucquoy, Dautzenberg, and Dollfus, 1882 Trophonopsis Bucquoy, Dautzenberg, and Dollfus, MoU. Mar. RoussiUon, Vol. 1, p. 40, 1882. Type (by original designation), Murex muricatus Montagu, Test. Brit., p. 262, pi. 9, fig. 2, 1803 ( + Murex variabilis Christofori and Jan., 1832, + Fusus echinatus Sowerby, Philippi, Enum. Moll. Sic, Vol. 1, p. 200, pi. 11, fig. 10, Vol. 2, p. 179, 1836-44, + Fusus longurio Weinkauff, Journ. de Conchyl., Vol. 14, p. 244, pi. 5, fig. 4, ISG8, fide Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. RoussiUon, Vol. 1, p. 39, figured on pi. 6, fig. 7, 1882), Mediterranean, Atlantic coasts of Europe, possibly to northeastern North America, Recent, also Pliocene of England. Shell like that of Boreotrophon but with prominent spiral sculpture and secondary axial sculpture. Trophon (Trophonopsis) tenuisculptus Carpenter Trophon tenuisculptus Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 17, p. 277, 1866; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 70, 1868-9; Cooper, 7th Ann. Rept., Calif. State Mineralogist, p. 268, 1888. Trophon {Boreotrophon) tenuisculptus Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 253, 1903. Boreotrophon tenuisculpta Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 24, p. 541, 1902; Van Winkle, Bull. Amer. Paleo., Vol. 8, p. 351, pi. 1, figs. 6-9, 1921 (figure of type specimen). Neptunea tenuisculpta Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. ill, pi. 11, figs. 11, 12, 1921. Trophon (Neptunea) tenuisculptus Carpenter, Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 39, pi. 30, figs. 3, 7, 1927. Type specimen: At Cornell University, Ithaca, New York. Type locality: Santa Barbara, fossil, said to be Pleistocene, but cjuite likely to be upper Pliocene (Santa Barbara zone). ? U. Pliocene: Type locality (?). Pleistocene: "Pliocene" of San Pedro district, "rare" (Arnold); Santa Barbara (Carpenter). Recent: Southeastern Bering Sea to Todos Santos Bay, Lower California, Mexico (Dall, 1921). Genus FORRERIA Jousseaume, 1880 Forreria Jousseaume, Le Naturaliste, 2nd year, No. 42, p. 335, December 15, 1880.' "Chorus Gray," of various authors, not of Gray, Proc. Zool. Soc. London for 1847, p. 136, 1847, type bj- original designation, Monoceros giganteus Lesson. Type (by original designation) Murex belcheri Hinds. ^ In thia short article, Jousseaume lists forty-seven genera, subgenera, and sections of the Muricids. stating their type species in each case. The following are given as new: Tubicauda, type, Murex brevisjnna Lamarck; Siratus, t^-pe, Purpura sirati Adanson; Paziella, type, Murex pazi Crosse; Poirieria, type, Murex zelandicus Quoy and Gaimard; Naquetia, type, Murex triqueter Born; Inermicosta, type, Murex fasciattta Sowerby; Favarlia, type, Murex breviculus Sowerby; Euphyllon, type, Murex monodon Sowerby; Ocinehrellus, type, Murex eurypleron Reeve; Gracili- purpura, type, Fusus strigosus Lamarck; Ocinihrina, type, Fusus coralinus Scacchi; Hanetia, type, Murex haneti Petit; Cra&silahrum, type, Murex crassilabrum Gray; Forreria, type, Murex belcheri Hinds; Jaiova, type. Purpura jatova Adanson; Pteropurpura, type, Murex macropterum Deshayes; Pterochelus, type, Murex acanihopierus; Marchia, type, Murex clavus Kiener; Purpurellus, type, Murex gambiensis Reeve; Poropteron, type, Murex tubifer; Typkinellus, type. Typhis sowerbyi Broderip; Typhina, type. Typhis belcheri Broderip; Siphonochelus , type. Typhis arcuatus Hinds; Typhisopsis, type, Typhis coronalus Broderip; Haustellotyphis, type. Typhis cumingi Broderip; Perotyphis, type. Typhis pinnatus Broderip. The last one is on page 336. Unfortunately, Jousseaume's paper was received too late to be used by the authors in studying the MuricidSE, 726 San Diego Society of Natural History [Memoirs Subgenus AUSTROTROPHON Ball, 1902 Austrolrophon Dall, Proc. U. S. Nat. Mus., Vol. 24, pp. 534, 548, March 31, 1902. Type (here designated), Trophon cerrosensis Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 181, pi. 5, figs. 5, 7, 1891.1 Shell of moderate size, with produced anterior canal, numerous lamellar varices which are pro- longed into points or spines on the shoulder of the whorls; spiral sculpture absent or weak. The peculiar leaf-like lamellae, which appear as if wrapped around the shell, suffi- ciently characterize this subgenus. The shell is of a light brownish color, which also appears to be characteristic of Forreria, s. s. Forreria (Austrotrophon) catalinensis (Oldroyd) 'Trophon Iriangiilatus Carpenter," Dall, Proc. U. S. Nat. Mus., Vol. 14, p. 180, in part, pi. 5, figs. 1, 6, not fig. 3, 1891, not of Carpenter. "Trophon {Boreotrophon) triangulatus Carpenter," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 254, 1903, not of Car- penter. "Trophon (Austrophon) triangulatus Carpenter," Dall, U. S. Nat. Mus., Bull. 112, p. 109, in part, 1921, not of Car- penter. Trophon {Austrotrophon) catalinensis I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 29, pi. 34, figs. 1-5, 1927. Type specimen: In the collection at Stanford University. Type locality: Off San Pedro, California, in 25 fathoms. Pleistocene: Lower San Pedro series of Deadman Island, Los Angeles County, "rare" (Arnold, as T. trian- gulatus). Recent: Catalina Island and San Pedro, California. Forreria catalinensis (Oldroyd) is very much larger than Trophon triangulatus Car- penter, with which it was for so long confused. It is probable that Cooper's report of Carpenter's species in the Pleistocene at Santa Barbara refers to T. catalinensis, but there is no way of deciding this point. Forreria (Austrotrophon) cerrosensis (Dall) is closely related but has more lamellar frills (about 10 per whorl instead of 6 or 7), and is usually smaller. The type of F. catalinensis is 100 mm. in length, has seven sharp lamellar frills and no spiral sculpture. A closely related or identical species occurs in the San Diego Pliocene (Hertlein and Grant, MS.). F. catalinensis differs from belcheri in having a much narrower body whorl anteriorly, in lacking the constriction in the middle of the body whorl of that species, and in its more extended lamellae. Subgenus FORRERIA, s. s. Forreria belcheri (Hinds) Murex belcheri Hinds, Proc. Zool. Soc. London for 1843, p. 127, March, 1844; Zool. Voy. Sulphur, Moll., p. 8, pi. 2, figs. 1, 2, 3, 1844. Pyrula belcheri Hinds, Reeve, Conch. Icon., Vol. 4, Pyrula, pi. 2, fig. 4, 1847. Chorus belcheri Hinds, Tryon, Man. Conch., Ser. 1, Vol. 2, p. 198, pi. 61, fig. 309, 1880; Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 235, 1888; Keep, West Coast Shells, p. 25, fig. 7, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 247, 1903; Orcutt, MoUuscan World, p. 6, 1915. Forreria belcheri Hinds, Dall, U. S. Nat. Mus., Bull. 112, p. 113, 1921; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; Jordan and Hertlein, Vol. 15, p. 419, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 49, pi. 32, figs. 2, 5, 1927. ' The type locality is off Ccdros Island, Lower Califoruia. Mexico, in 12 to 48 fathoms, mud and sand. Mr. George Willett, of the Los Angeles Museum, has collected this species in 30 fathoms off Catalina Island. California. Volume I | PlIOCEXE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 727 Type locality: San Diego, California, Recent. Pliocene: San Diego well (Dall); Rustic Canyon, Santa Monica (coll. by Carson; possibly Pleistocene?); Turtle Bay, Lower California, Mexico (Jordan and Hertlein). Pleistocene: Barlow's Ranch, near Ventura; upper San Pedro series at Crawfish George's, Los Cerritos, and San Pedro, Los Angeles County, "rare" (Arnold). Recent: San Pedro, California, to Scammon's Lagoon, Lower California, Mexico (Dall, 1921). Forreria belcheri (Hinds) is a rather large shell with quadrate whorls handsomely coronated with hollow, trough-like spines. The body whorl is rather abruptly constricted anteriorly, a slight sulcus being reflected at the aperture by a projecting tooth on the outer lip, as in PseudoUva. In general aspect the shell recalls Forreria catalinensis (I. S. Oldroyd), but the thin, expanded varices of the latter are in belcheri closely welded to the sides of the whorl and the shell of Hinds' species is heavier, more quadrate in shape, and has a relatively shorter and more bent anterior canal and a more open umbilicus. The genus Forreria may be related to Trophon through such species, that is, via Austrotrophon. Forreria belcheri (Hinds) variety avita (Nomland) "Trophon (Forreria) ponderosinn Gabb," Arnold, U. S. Geol. Surv., Bull. 396, p. 134, pi. 14, figs. 3, .5, 6, January 15, 1910; Bull. 398, pi. 36, same figures, 1910, not Trophon ponderosum Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 2, pi. 1, fig. 3, 1866, =Thais (Stramonila) ponderosa (Gabb). "Trophon ponderosus Gabb," McLaughlin and Waring, Map folio accompanying Bull. 69, Calif. St. Mining Bureau, pi. 1, fig. 41, 1914. Trophon belcheri anlum Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 237, pi. 11, fig. 5, April 19, 1917. Type specimen: In the collection of the University of California, No. 11,094. Type locality : In the Coalinga region, San Joaquin basin, California, Pliocene. Pliocene: Rare in the Turritella nova zone, lower part of the Etchegoin of the Coalinga region (Nomland). There is very little difference between this variety and typical belcheri, aside from the imperfections due to erosion and weathering. Forreria magister (Nomland) Plate 27, Figures 14a, 146 Trophon magister Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 207, pi. 11, figs. 4a, 46, 4r, February 24, 1916. Type specimen: In the collection at the University of California. Type locality: On Jacalitos Creek or Waltham Creek, Coalinga district, California, lower Pliocene. Pliocene: Jacalitos formation in the Coalinga district (Nomland); S. D. S. N. H. locality 203, lower Pliocene of Elsmere Canyon, Los Angeles County (H. R. G.). This is a large, massive, rude species with broad, low nodosities on the shoulder of the whorls and a deep constriction on the anterior portion of the body whorl. Forreria carisaensis (Anderson) Chorus carisaensis F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 3, Vol. 2, p. 206, pi. 17, figs. 90, 91, December 4, 1905. Trophon carisaensis Anderson, Arnold, U. S. Geol. Surv., Bull. 396, pi. 10, fig. 4, January 15, 1910; Bull. 398, pi. 32, fig. 4, 1910; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 497, pi. 66, figs. 1, 2, 1915; Nomland, Vol. 10, pp. 299, 301, 1917. Type specimen: In the collection at the California Academy of Sciences, if not lost in the San Francisco earthquake. 728 San Diego Society of Natural History [Memoirs Type locality: Near La Panza Springs, San Luis Obispo County, lower Pliocene. Miocene: Questionably the "Vaqueros-Temblor" (Nomland); San Pablo formation north of Mount Diablo, Las Tiampas, and Rocky Ridges (Clark) ; Santa Margarita formation, upper Miocene of Coalinga district (Arnold; Nomland). Pliocene: "Lower Etchegoin beds of the Mount Diablo Range, near La Panza Springs, San Luis Obispo County" (Anderson). Forreria carisaensis (Anderson) is larger and has fewer but much more prominent nodes on the shoulders of the whorls than has Chicoreus wilkesanus. Some of the later names, such as coalingensis, magister, and avita, may later be found to be synonyms. Forreria wrighti Jordan and Hertlein Forreria xmghti Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 448, pi. 32, figs. 1, 3, July 22, 1926. Type specimen: At the Cahfornia Academy of Sciences, No. 2123. Tijpe locality: Southeast of Turtle Bay, Lower Cahfornia, Mexico, Phocene. Pliocene: Southeast of Turtle Bay, Lower California, Mexico (Jordan and Hertlein). This species has spiral riblets which are particularly emphasized on the whorls of the spire in addition to axial sculpture wliich produces a crown of spines on the shoulders. Forreria coalingensis (Arnold) Trophon (Forreria) coalingcnse Arnold, V. S. Geol. Surv., Bull. 396, p. 87, pi. 22, fig. 4, January 15, 1910; Bull. 398, pi. 44, same figure, 1910. Trophon coalingense Arnold, Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 203, 1916; Vol. 10, p. 221, 1917. Type specimen: In the U. S. National Museum, No. 165,540. Type locality: Extreme southeastern end of Kettleman Hills, San Joaquin basin, California, Pliocene. Plioceve: Jacalitos formation of Jacalitos and Waltham canyons, Coalinga district, lower Pliocene (Nom- land, 1916) ; Etchegoin formation on south side of Garza Creek and at southeastern end of Kettleman Hills, Coalinga district (Arnold); "rare" in the Chione elsmerensis zone, lower Pliocene of the Coalinga region (Nomland, 1917). Genus CHICOREUS Montfort, 1810 Chicoreus Montfort, Conch. Syst., Vol. 2, p. 611, 1810. Triplex Perry, Arcana, pi. 23, June, 1810, type (by monotypy), Triplex foliatiis Perry, pi. 23, 1810, + Triplex rosaria Perry, Conchology, pi. 6, fig. 3, April, 1811, + Murex palmarosse Lamarck; Matthews and Iredale, Victorian Naturalist, Vol. 29, p. 11, 1912. Type (by original designation), Murex ramosus Linnseus, Syst. Nat., Ed. 10, p. 747, 1758; figured by Reeve, Conch. Icon., Vol. 3, Murex, pi. 1, species 3, April, 1845; Recent, in the Orient. Shell large, stout; sculpture of three or more lamellar varices, sometimes spiny; anterior canal rather short, strongly recurved, partly covered by a flap. Distribution: Warm waters. Montfort's figure of C. ramosus is rather elongate for that species; but even if it should represent a different, though closely allied species, it could not affect the use of the genus name. C. ramosus is clearly congeneric with the type of Phyllonotus. It has three varices with strong lamellar spines and three without, whereas Phyllonotus has six or more varices which are apt to be all alike, either without spinous lamellae or with only moderate ones. In other characteristics the two agree, and the distinction is at Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 729 most subgeneric, perhaps only sectional. The new group, Murithais, has small, simple nodes on the angle and occasionally smaller ones below, but the varices are hardly more than indistinct axial ribs, dying out downward. It is distinguished from Forreria by the lack of the angulation on the lower part of the body whorl and by the more compact form of its nodes. As it seems to be most like Forreria, it will be considered ahead of PhyUonotus. Phyllonotus and Muricanthus are even more closely related to typical Chicoreus than is Murithais and should probably be separated only as sections, if at all. Perry's name, Triplex, may be older than Chicoreus. Subgenus MURITHAIS, new subgenus Type, Murex trunculus Linnaeus, Syst. Nat., Ed. 10, p. 747, 1758; good figures by Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, p. 18, pi. 1, figs. 3, 4, 1882; the figures by Reeve, Conch. Icon., Vol. 3, Murex, pi. 5, species 22, May, 1845, are more ornate than is usual for this variable species; Mediterranean, Recent. Shell like that of Phyllonotus but usually smaller, with shorter anterior canal, less distinct varices, and more compact nodes. This group seems to be equally difficult to distinguish from several well-known groups that are ordinarily not considered very much alike. It is most closely allied to Chicoreus and Phyllonotus, as noted above; but it is also connected with Thais through such species as T. ponderosa. Indeed, ponderosa as figured by Clark is so very much like wilkesanus that it seems not unlikely that ponderosa and perhaps also Ball's im- perialis should be transferred to this group. On the other hand, Miocene species of Forreria approach very closely to wilkesanus and appear also to be closely related. Immature specimens of topangensis (Arnold)' in the collection at the Los Angeles Museum from the Santa Monica Mountains bear such a striking resemblance to Recent specimens from Ceylon of Cantharus tranquebaricus, the type of Cantharus, in size, shape, and sculpture that the writers did not see any characters by which to distinguish them. In this case the relationship may not be so close, for the adults of topangensis lose some- what their resemblance to tranquebaricus and show that topangensis is either a synonym or a species closely related to ivUkesanus. Some of the west American species of Cayi- tharus look less like tranquebaricus than does the young of topangensis and perhaps some of them are more nearly allied to Searlesia, especially humerosus; but they are connected with tranquebaricus through such species as anomalus. This case is one of the many disconcerting connections between the Neptuneidce and the Muricidee. Some writers explain the resemblances as due to the coincidences of parallel development; but the more of these coincidences appear between two particular groups, the less plausible this explanation becomes. Arnold described his topangensis as an Ocinebra (now known as Tritonalia), and he had good reason to see the close relationship of his species to that group. But the most striking and most significant resemblance is between wilkesanus and trunculus. The latter has more tabulated whorls than the specimen of wilkesanus figured here, but Anderson's type shows stronger tabulations. Siratus Jousseaume- is 1 Ocinfbra topangensis Arnold, Proc. U. S. Nat. Mus.. Vol. 32. p. 530, pi. 43, fig. 4, June 15, 1907; Bull. 309 U. S. Geol. Surv., p. 147, pi. 30, fig. 4 (same figure), 1907; Bull. 396, pi. 9. fig. 4, 1910, reprinted in Bull. 398, pi. 31, fig. 4, 1910; Temblor formation, middle Miocene of the Coalinga district and the Santa Monica Mountains. ' Siratus Jousseaume. Le Naturaliste, An. 2, p. 335. 1880, type (by original designation). Purpura sirati Adanson, = Le Siral Adanson, Hist. Nat. du S^n^gal, p. 125, pi. 8, fig. 19, 1757, = Murex senigalensis Gmelin, Syst. Nat., Ed. 13, p. 3537, 1790. figured by Reeve, Conch, Icon., Murex, pi. 24, species 101, Aug., 1845; Senegal, Recent. 730 San Diego Society of Natural History [Memoirs intermediate between trunculus and the true Murex and not very far from either. Its anterior canal is much longer than that of trunculus and it tends to be more spinose. Clearly there are links between all the Muricidce. Chicoreus (Murithais) wilkesanus (Anderson) Plate 32, Figure 12 Fusus (Hemifvsus) unlkesana F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 3 (Geol.), Vol. 2, p. 205, pi. 16, figs. SI, 82, December 4, 1905. Type specimen: In the collection of the California Academy of Sciences, if not lost in the San Francisco earthquake. Type locality: Rreyenhagen oil wells, Kings County, California, lower middle Miocene. Miocene: Temblor formation, lower middle Miocene of Kreyenhagen oil wells, Kings County (Anderson); Superior Oil Company's well, Ansolabehere No. 1, northwest of Bakersfield, upper or possibly middle Miocene (H. R. G.). Subgenus PHYLLONOTUS Swainson, 1833 Phyllonotus Swainson, Zool. lUust., Ser. 2, Vol. 3, pi. 109, 1833; Treat. Malac, p. 296, 1840; Woodring, Carnegie Inst., Publ. No. 385, p. 289, 1928. Type (by monotypy), Murex (Phyllonotus) imperialis Swainson, = M. pomum GmeUn, figured by Tryon, Man. Conch., Ser. 1, Vol. 2, p. 97, pi. 20, fig. 182, 1880; also figured by Woodring, op. cit., p. 290, pi. 17, fig. 9, 1928; Recent, West Indies, also Miocene of Bowden, Jamaica, and of Colombia, and Miocene or Pliocene of North Carolina. Chicoreus (Phyllonotus) hippocastanum (Philippi) Murex hicolor Valenciennes, Humboldt's Voy. Inter. Amer., Obs. Zool., Vol. 2, p. 301, 1832; Reeve, Conch. Icon., Vol. 3, Murex, pi. 11, fig. 44, 1845; Tryon, Man. Conch., Ser. 1, Vol. 2, p. 101, pi. 23, fig. 204, 1880; not Murex bicolor Risso, 1826, nor Renier, 1804. Murex hippocaslamtni Philippi, Abbild. Beschreib., Vol. 1, Heft 8, p. 1, pi. 1, fig. 2, January, 1845; young specimen ? Phyllonotus bicolor Va'enciennes, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 218, 1909; Nautilus, Vol. 32, p. 23, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 1918); upper Quaternary at San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Guaymas, Mexico, to Paita, Peru (Dall, 1909). Chicoreus (Phyllonotus) princeps (Broderip) Murex princeps Broderip, Proc. Zool. Soc. London for 1832, p. 175; Reeve, Conch. Icon., Vol. 3, Murex, pi. 6, fig. 23, May, 1845; Sowerby, Thes. Conch., Vol. 4, Murex, p. 33, pi. 19, figs. 175, 176, 1880. Murex (Phyllonotus) princeps Broderip, Tryon, Man. Conch., Ser. 1, Vol. 2, p. 106, pi. 28, fig. 250, 1880. Phyllonotus princeps Broderip, Dall, Nautilus, Vol. 32, p. 23, 1918. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall). Recent: West coast of Mexico and Central America. Chicoreus (Phyllonotus) steamsii (Dall) Murex (Phyllonotus) steamsii Dall, Nautilus, Vol. 32, p. 26, July, 1918. Type specimen: In the U. S. National Museum. Type locality: "Fossil on Magdalena Island," Lower California, Mexico. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall). Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 731 Subgenus MURICANTHUS Swainson, 1840 Cenlronotus Swainson, Zool. 111., Ser. 2, Vol. 3, no. 22, pi. 100, 1833, not Cenlronotus Lacepede, 1802, nor Schneider, 1801. Muricanthus Swainson, Treat. Malac, p. 296, May, 1840, species included, radix Sow., Zool. 111., Ser. 2, pi. 113, and melanomathus, Ency. M^th., pi. 418, fig. 2; Herrmannsen, Ind. Gen. Malac, Vol. 2, p. 69, July 17, 1847; Gray, Proc. Zool. Soc. London, p. 133, Nov., 1847. Type (by subsequent designation, Herrmannsen and Gray, 1847), Murex radix Swainson. Shell like that of Phyllonolus but with more numerous lamellar varices, the edges of which are raised up into many moderately short, trigonal lamellar spines; the spire low, the body whorl large, rounded. This group, which should probably not be more than a section, is as different from Phyllonolus as the latter is from Chicoreus; but the differences are very small. Chicoreus (Muricanthus) radix (Gmelin) Murex radix Gmelin, Syst. Nat., Ed. 13, p. 3527, 1790; Lamarck, Hist. Anim. s. Vert., Vol. 7, p. 168, 1822; Tryon, Man. Conch., Ser. 1, Vol. 2, p. 10.5, pi. 27, figs. 244, 247, 248, 1880. Phyllonolus radix Lamarck, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 219, 1909; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 151, 1924. Pleistocene: Upper Quaternary of San Ignacio Lagoon, Lower California (Jordan), and upper Pleistocene of coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Acapulco, Mexico, southward to Panama and Paita, Peru (Dall). Superfamily Taenioglossa Family BURSIDAE The Bursidoe, formerly called the Ranellidce, differ from the Muricidce in radular characters and in the less often closed anterior canal and from the Cymatiidce in having a well-developed posterior canal. Ball's "Review of the Frogshells and Tritons"' con- tains information and references to early literature; but the family and related families now stand in need of revision, both in classification and nomenclature. Genus BURSA Bolten, 1798 Bursa Bolten, Mus. Boltenianum, Pt. 2, p. 128, 1798; Jousseaume, Bull. Soc. Zool. France, Vol. 6, p. 174, 1881; Cooke, Proc. Malac. Soc. London, Vol. 12, p. 5, 1916; Woodring, Carnegie Inst., Publ. No. 385, p. 302, 1928. Type (by subsequent designation, Jousseaume, 1881), Bursa monitata Bolten, = Murex bufonius Gmelin, figured by Tryon, Man. Conch., Ser. 1, Vol. 3, p. 39, pi. 19, fig. 11, pi. 21, figs. 21, 22, 23, 1881; Indo-Pacific, Recent. Shell ovate, rather compact, with two continuous opposite varices or protruding nodosities; aperture ovate, with a well-marked posterior canal and an open, curved anterior canal; columella arcuated or ridged. Bursa califomica Hinds Ranella califomica Hinds, Ann. Nat. Hist., Vol. 11, p. 255, April, 1843; Zool. Voy. Sulphur, Moll., p. 12, pi. 2, figs. 4, 5, 1844; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 73, 1868-9; Keep, West Coast Shells, p. 44, fig. 24, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 287, 1903. Ranella {Lampas) califomica Hinds, Tryon, Man. Conch., Ser. 1, Vol. 3, p. 40, pi. 22, fig. 42, 1881. Bursa (Bufonaria) califomica Hinds, Dall, U. S. Nat. Mus., Bull. 112, p. 141, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 241, pi. 33, figs. 7, 8, 1927. Bursa califomica Hinds, E. K. Jordan, Bull. So. Calif. Acad. So ., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. ' Smithsonian Misc. Coll., Vol. 47, pp. 114-144, 1904. 732 San Diego Society of Natural History [Memoirs Type locality: San Diego, California, Recent. Pliocene: Ivirker's Pass (fide Arnold); "Fernando" of Puente Hills, Los Angeles County (coll. by R. N. Ferguson). Pleistocene: Upper San Pedro series in San Pedro region; Pleistocene at Pacific Beach, San Diego (Arnold); lower Quaternary of Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower California, Me-xico (Jordan, 1924, 1926). Recent: Monterey, California, to Cedros Island, Lower California, Mexico (Dall, 1921). Bursa ventricosa (Broderip) of the Peruvian Recent fauna is very similar in general aspect but is more ventricose, with a thinner shell, lower spire, and smoother surface. Family CYMATIIDAE The type of Cymatium^ is a peculiar shell, with three very large varices and a long, almost closed anterior canal. The Cymatiido' intergrade with the MuricidcB as well as with the Bursidce. All of these families need revision. Genus CABESTANA Eolten, 1798 Cahestana Bolten, Mus. Boltenianum, p. 130, 1798, Murex cutaceus Linnseus included; Dall, Smithsonian Misc. Coll., Vol. 47, p. 134, 1904. Aquillus Montfort, Conchyl. Syst., Vol. 2, p. 578, 1810, type (by original designation), Murex cutaceus Linnaeus. Turritriton Dall, Smithsonian Misc. Coll., Vol. 47, p. 133, Aug. 6, 1904, type (by original designation), Triton gibbosus Broderip. Type (by subsequent designation, Dall, 1904), Murex cutaceus Linnseus, Syst. Nat., Ed. 12, p. 1217, 1767; figured by Reeve, Conch. Icon., Vol. 2, Triton, pi. 11, species 39, May, 1844; Mediterranean. Shell of moderate size, or small, thick for its size, with one and a half varices to a whorl (three varices to two whorls, giving the shell a trigonal appearance), whorls tabulated, with rounded nodes on the angle between the varices, minor sculpture of spiral ridges covered with small pustules; spire short, body whorl large, anterior canal short, aperture romaded, outer lip denticulated. Cahestana is so much hke Cymatium that it may well be and often has been considered a subgenus of Cymatium. However, the latter is much larger, has very large, prominent varices with high shoulders, a very elongate, expanded, trigonal aperture, and a narrow, curving anterior canal. Turritriton, on the other hand, is hardly of sectional value. C. gibbosa differs only in having a very sUghtly longer anterior canal and less developed siphonal fasciole. It is a variable species. One form figured by Kobelt and the figure reproduced by Tryon shows sutures sunken below the level of the tabulation. This appears to be the more characteristic form and is most common in the collections. However, another form figured by Reeve and one of the figures also reproduced by Tryon has less marked tabulations and higher sutures. The two forms, though differing in appearance, are probably conspecific. The latter shows the close relationship between this group and Septa Perry, = of which Lampusia Schumacher^ is probably a synonym. ' Cymatium Bolten, Mus. Boltenianum, p. 129, 1898, type (by subsequent designation, Dall, Smithsonian Misc. Coll., Vol. 47, p. 133, 1904) Murex femorale Linnseus. 2 Septa Perry. Arcana, pi. 2, Jan. 1, 1810, type Gsy monotypy). Septa scarlatina Perry, pi. 2, fig. 2. also figured in Perry's Conchology, pi. 14, fig. 2, April, 1811, = Murex rubecula Linnaus, Syst. Nat., Ed. 10, p. 749, 175S; Matthews and Iredale, Victorian Naturalist, Vol. 29, pp. 9, 10, 1912. • Lampusia Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 250, 1817, two sections included, the first typified by Murex pileare Lm- nasus, Chemnitz, NeuesSyst. Conch. Cab., Vol. 4, p. 89, pi. 130, figs. 1242, 1243, 1248, 1249, pi. 131, figs. 1250, 1251, 1780, and Vol. 11, p. 115, pi. 191, figs. 1837, 1838, dated 1795, the second typified by Murex Irilonis Linnaius. Chemnitz, Vol. 4, p. 112, pi. 134, figs. 1277, 1280, 1281, pi. 135, figs. 1282, 1283, 1780; Herrmannsen, Ind. Gen. Malac, Vol. 1, p. 575, May 25, 1847; Gray, Proc. Zool. Soc. London for 1847, p. 133, Nov., 1847; Woodring, Carnegie Inst. Wash., Publ. No. 385, p. 297, 1928; type (by subsequent designation, Herrmannsen and Gray, IS-l?)- Murex pileare Linnaius, Syst. Nat., Ed. 10, p. 749, 1758, figured by Reeve, Conch. Icon., Vol. 2, TrUon, pi. 7, fig. 23, April, 1844, Philippine Islands, Recent. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 733 Septa could be considered a subgenus with the whorls not tabulated, the spire high, and no large nodes on the angle between the varices to break the even curve of the pustulated spirals. Gutturnium'- is also similar and could be considered a subgenus with the whorls not tabulated, the minor sculpture finer, the anterior canal longer and strongly bent back, and the inner Up and body whorl spread with a thick, wide deposit of callus. The inner hp of gibbosa is not extended and has a distinct edge. C. exarata (Reeve)- is similar to gibbosa in general appearance. Gyrineum has a small, heavy shell, with its varices arranged bilaterally and extending continuously from whorl to whorl up the spire. It is not known whether this distinction is of importance or not. Cabestana gibbosa (Broderip) Triton gibbosus Broderip, Proc. Zool. Soc. London, Pt. 1, p. 7, May, 1833; Reeve, Conch. Icon., Vol. 2, Triton, pi. 11., fig. 38, pi. 14, figs. 38b, 38c, 1844; Cooper, Calif. State Mining Bureau, Bull. No. 4, Pt. 3, p. 32, 1894. Triton {Gulturnium) gibbosus Broderip, Tryon, Man. Conch., Ser. 1, Vol. 3, p. 23, pi. 12, figs. 101, 103, 1881. Tritonium gibbosus Broderip, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 286, 1903. Cymalium gibbostim Broderip, Ball, Proc. U. S. Nat. Mus., Vol. 37, p. 225, 1909; U. S. Nat. Mus., BuU. 112, p. 141, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 243, 1927. Type specimen: In the British Museum. Type locality: Panama, Recent. Pleistocene: Rare in upper San Pedro series of San Pedro, Los .\ngeles County (Arnold). Recent: San Pedro, California, to Panama (Dall, 1921); Panama to Guayaquil (Dall, 1909). The varices of this species are not continuous, those on the spire being offset from those on the body whorl. Genus GYRINEUM Link, 1807 Gyrineum Link, Beschr. Natur.-Samml. Univ. Rostock, Pt. 2, p. 123, 1807, fide Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 384, footnote, 1927; Dall, Smithsonian Misc. Coll., Vol. 47, p. 131, Quarterly Issue, Aug. 6, 1904. Apollon Montfort, Conehyl. Syst., Vol. 2, p. 571, 1810, type (by original designation), Murex gyrinus Linnaius. Apollo Montfort em., Harris, Cat. Tert. Moll. Brit. Mus., Pt. 1, p. 195, 1897, type stated, Murex gyrinus Linnaus. Type (by subsequent designation, Dall, 1904), Murex gyrinus Linnseus, figured by Tryon, Man. Conch., Ser. 1, Vol. 3, p. 43, pi. 23, fig. 48, 1881; Australia, Recent. Shell small, ovate or oblong, with two varices, which are generally continuous and opposite; anterior canal short. Gyrineum elsmerense English ? Triton sp., .\rnold, Proc. U. S. Nat. Mus., Vol. 32, pi. 50, fig. 5, 1907. Gyrineum elsm^ense English, Univ. Calif. Publ. Geol., Vol. 8, p. 215, pi. 23, fig. 6, 1914. Type specimen: In the collection at the University of California. Type locality: Elsmere Canyon, Los Angeles County, PUocene. Pliocene: Lower Pliocene of Elsmere Canyon, Los Angeles County (English). This species seems to be appropriately placed in Gyrineum, though it may be related to the Ranellas. ' Gutturnium Klein, Ostrac, p. 51, 1753, pre-Linnffian; Herrmannsen. Ind. Gen. Malac, Vol. 1, p. 492. May 25, 1847, not validated; Morch, Cat. Yoldi, Pt. 1, p. 109. 1852. T. tuberosum Lamarck included; Dall. Smithsonian Misc. Coll.. Vol. 47, p. 133. 1904; Woodring, Car- negie Inst. Wash., Publ. No. 385, p. 298. 1928; type (by subsequent designation, Dall. 1904), Triton tuberosum Lamarck, figured as Triton luberosus Lamarck by Reeve. Conch. Icon., Vol. 2, Triton, pi. 1, species 1. March, 1844, West Indies. Recent. = Triton exaratus Reeve, Conch. Icon., Vol. 2, Trittm, pi. 13, species 50. June, 1844; Australia and New Zealand. 734 San Diego Society of Natural History iMemoirs Genus RANELLA Lamarck, 1816 Ranelle Lamarck, Extr. Cours. Zool., 1812, vernacular use only. Ranella Lamarck, Ency. Meth., Vers, pis. 413, 414, list, p. 4, 1816; Children, Quart. Journ. Sci., Lit., and the Arts, Vol. 16, p. 49, Oct., 1823. Not "Ranella Lamarck," of various authors, = Bursa. Gyrina Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 253, 1817, type (by monotypy) Gyrina maculata = Buc- cinum reliculatum Chemnitz, Neues Syst. Conch. Cab., Vol. 4, p. 80, pi. 128, fig. 1228, 1780. Eugyrina Dall, Smithsonian Misc. Coll., Vol. 47, p. 132, Aug. 6, 1904, type (by original designation) Ranella giganlea Lamarck; Cooke, Proc. Malac. Soc. London, Vol. 12, p. 3, 1916. Trjpe (by subsequent designation, Children, 1823), Ranella giganlea Lamarck, Ency. Meth., pi. 413, list, p. 4, 1816; figured by Born, Test. Mus. Cffis. Vind., p. 301, pi. 11, fig. 5, 1780 as Murex reticularis Linnaeus and by Children, pi. 5, fig. 181, who says it is the same as Murex reticularis Linnaeus; see also Deshayes in Lamarck, Hist. Nat. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 9, p. 540, 1843, who also calls it Ranella reticularis; figured by Reeve, Conch. Icon., Vol. 2, Ranella, pi. 1, species 3, July, 1844; Bucquoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, p. 28, pi. 3, fig. 1, 1882, say it is not reticularis, as Hanley identified Linnaeus' type as R. tuberculata Broderip; Hanley says (Ipsa Linnei Conchylia, p. 287, 1855) that according to Linnaeus' type specimen Ranella gigantea Lamarck is Murex olearium Linnaeus; Mediterranean, Recent. Shell large but not very heavj', with a high spire, rounded whorls, and short anterior canal; sculptured with rounded axial ribs and spiral ridges which become slightly nodular at the inter- sections, often with one or more of the axial ribs accentuated above the others in the form of a varix, typically with the varices well marked, two to a whorl and only slightly offset from whorl to whorl up the spire; aperture rounded, ofteia with a moderate number of rounded denticles inside the outer lip at the varix stage, these denticles sometimes obsolete, and a prominence near the top of the inner lip; hairy epidermis usually conspicuous. This genus might be considered a subgenus of Gyrineum; but it is much larger, with a relatively thinner shell, and seems to be less tropical in distribution. It has about the same shape and is connected by such species as R. cruentata Sowerby and R. affinis Broderip. Another older name that must be considered for this genus is Monoplex Perry.' If M. australasice should be properly designated as the type, Monoplex might not be more than subgenerically distinct from Ranella. M. australasice- is characterized by a few, rather large, square-shouldered spiral ridges, a shell that is not very heavy, with a terminal varix only, the outer lip not much thickened. Perry's other species belong to entirely different groups. Argobuccinum should not be used as of Morch, 1852, but of Klein in Herrmannsen, 1846, with the type Murex argus Linnaeus by original designation. Buffo Montfort, 1810, not Buffo Lacepede, 1788, nor Bufo Laurenti, 1768, is a synonym. Argobuccinum can be used as a section of Ranella with short ovate shell and weak sculpture covered with a heavy epidermis. 1 Monoplex Perry, Conchology, or the Natural History of Shells, pi. 3, 1811, five species included: fig. 1, comutus; fig. 2, oboeaus; fig. 3 australasise; fig. 4. capilatus; fig. 5. formosus: all new species. So far as the writers have been able to ascertain, no one of these species has been selected as the type. Gray, Herrmannsen, Dall, and others have cited Triton succincium Lamarck, Murex olearium Linnseus, or other names of which Perry's third species may be a synonym; but as these names are not referred to by Perry, these citations cannot be accepted as fixing the type. Dall came the nearest to it when he said (Smithsonian Misc. Coll., Vol. 47, p. 138, 1904) that Gray selected T. olearium (L.) Reeve, = Monoplex australasise Perry, fig. 3, = M. costatus Born. However, Gray did not mention Perry's species and it is doubtful whether Ball's saying that he did when he didn't would constitute designation, especially as Reeve's olearium and M. costatus Born are appar- ently not the same as australasis. Pilsbry (Proc. Acad. Nat. .Sci. Phila., Vol. 56 (for 1901), p. 22, Feb. 10, 1904) cited cynocephalus Lamarck, which may be the same as Perry's first species; but this citation cannot be regarded as fixing the type. This species has a rather low spire and a rather long, narrow, curving canal, but it is not so extreme as Murex clavator, the type of Ranula and Banularia Schumacher, 1817. If Perry's first species should become the type of Monoplex, then Gutlurnium Klein in Morch, 1852, with Triton tuberosum Lamarck as the type, would probably become a synonym. 2 Accessible figures that are really of this species are hard to find. Tryon figures it as Triton (Simpulum) olearium Linnaeus, Man. Conch., Vol. 3, p. 11, pi. 6, fig. 37 (only), 1881. Reeve's figure. Conch. Icon., Vol. 2, pi. 10, fig. 32, May, 1844, is not of this species. Simpulum Klein in Morch. 1852. might have been a name available for this group, but apparently the name had been previously employed by Fabricius, 1S23. VoLTTME 1 1 Pliocene and Pleistocene Mollusca of California 735 Subgenus RANELLA, s. s. Shell large, not very hea\^', with rather strong, opposite varices only slightly offset up the spire, and low denticles on the inside of the outer lip. RanelJa diUeri (Anderson and Martin), according to its figure, is so much like R. gigantea that there appears to be no way of distinguishing it even specifically.^ All the groups of Ranella are probably closely related, and the distinctions between them may be of little value. The differences between dilleri and oregonensis are not very great. Subgenus PRIENE H. and A. Adams, 1858 Priene H. and A. Adams, Gen. Rec. Moll., Vol. 2, p. 654, Nov., 18.58, in the addenda and errata, changing the name Argobuccinum Ivlein as used on page 104, Volume 1, to Priene, species included, rude Broderip and scabrum King; Cossmann, Ess. Paleo. Comp., Vol. 5, p. 109, 1903. Type (by subsequent designation, Co.ssmann, 1903), Triton scaber King; figured by Reeve, Conch. Icon., Vol. 2, Triton, pi. 11, species 34, May, 1844; west coast of South America. Shell like that of typical Ranella, but shorter, heavier, the varices less accentuated and less regular, the axial ribs better developed or at least more nearly continuous from the top to the bottom of each whorl. Section Priene, s. s. Shell short, rather heavy, apt to have denticles on the inside of the outer lip. Ranella (Priene) pacifica (Dall) Argohuccinum {Priene) pacifiea Dall, Prof. Paper 59 U. S. Geol. Surv., p. 56, pi. 5, fig. 9, pi. 6, fig. 2, 1909; Howe, Univ. Calif. Publ. Geol., Vol. 14, table opposite p. 93, 1922. U. Miocene: Coos Bay, Oregon (Dall; Howe). ? Pliocene: Purisima formation of Santa Cruz County, California (Arnold in Dall). This form is almost exactly like R. scabra (King) and may even be conspecific with it. It is probable also that corbiculata and coosensis are only varieties or variations, occurring in the same deposits, and even mediocris may also belong in the same species. The Purisima specimens grade into oregonensis and are probably conspecific with oregonensis. Ranella (Priene) corbiculata (Dall) Gyrineum {mediocre var. ?) corbiculalum Dall, Prof. Paper 59, U. S. Geol. Surv., p. 55, pi. 7, fig. 9, April 2, 1909. Argobuccinum (Fasilriton) coosense Dall, Prof. Paper 59, U. S. Geol. Surv., p. 55, pi. 7, fig. 4, April 2, 1909. Argohuccinum coosense Dall, Arnold and Hannibal, Proc. Amer. Phil. Soc, Vol. 52, p. 590, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 32, 1916; Howe, Univ. Calif. Publ. Geol., Vol. 14, table opposite p. 93, 1922. Bursa trampasensis Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 492, pi. 67, fig. 3, 1915. Gyrineum mediocre var. corbiculalum Dall, Weaver, Univ. Wash. Publ. Geol., Vol. 1, no. 1, p. 32, 1916. Gyrineum corbiculalum Dall, Howe, Univ. Calif. Publ. Geol., Vol. 14, table opposite p. 93, 1922. Type specimens: Of corbiculata and coosensis, in the U. S. National Museum, cor- biculata No. 153,870, coosensis No. 153,903; of trampasensis, at the University of Cali- fornia. Type localities: Of corbiculata and coosensis, Miocene of Coos Bay, Oregon; of trampasensis, lower San Pablo formation of middle California. • Argohuccinum dilleri Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 71, pi. 4, fig. 7, 1914; Miocene of Oregon. 736 San Diego Society of Natural History [Memoirs U. Miocene: Empire formation of Coos Bay, Oregon (Dall) ; Montesano formation of Washington (Weaver) ; San Pablo of Las Trampas Ridge (Clark). Pliocene: Coos Conglomerate, Coos Bay, Oregon (Howe). The reported range and characters of corbiculata and coosensis are almost exactly the same, and trampasensis has similar characters. Ranella (Priene) mediocris (Dall) Gyrineum mediocre Dall, U. S. Geol. Surv., Prof. Paper 59, p. 54, pi. 7, fig. 6, April 2, 1909; Amer. Journ. Sci., Ser. 5, Vol. 4, p. 313, 1922; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 93 and table opposite, 1922. Ranella marshalli Reagan, Trans. Kansas Acad. Sci., Vol. 22, p. 223, pi. 6, fig. 62, 1909; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916. Type specimens: Both in the U. S. National Museum. Type localities: Of mediocris, Coos Bay, Oregon, upper Miocene: of marshalli, Quil- layute, Washington, reworked upper Miocene deposit. Miocene: Montesano formation of Washington (Weaver); Empire formation of Coos Bay, Oregon (Dall); Quillayute formation, redeposited Miocene fossils, near QuiUayute, Washington (Reagan); Boga- chiel River, Washington (Dall). Pliocene: Coos conglomerate, Coos Bay, Oregon (Howe). This form may be but a variety of pacifica or corbiculata, as Dall suspected, bearing a relation to the other forms like that between the type and paratypes of lewisii. Ranella (Priene) lewisii (Carson) Gyrineum lewisii Carson, BuU. So. Calif. Acad. Sci., Vol. 25, p. 53, pi. 2, figs. 1, 2, 1926. Type specimen: In the type collection at Stanford University, No. 114. Type locality: Fugler's Point, Santa Maria district, Santa Barbara, California, Plio- cene. Pliocene: Lower Pliocene of Fugler's Point, Santa Barbara County (Carson). Carson's type specimen is a large shell with a nearly smooth surface except for the widely-spaced, spiral, impressed lines and the opposite varices. His paratype is different in appearance, having low axial undulations, and it may be a different species. However, it is likely that this group is subject to considerable individual variation and possibly several so-called species will have to be reduced to varieties or synonyms when more abundant material can be assembled. Carson's paratype of lewisii has a resemblance to Ranella mathewsonii (Gabb), which is an Oligocene species. Section Fusitriton Cossmann, 1903 Fiisitriton Cossmann, Ess. Pal^o. Comp., Vol. 5, p. 109, 1903. Type (by original designation), Triton cancellatum Lamarck, Ency. Meth., pi. 415, fig. 1, Liste, p. 4, 1816, see Hist. Nat. Anim. s. Vert., Desh. and M. Edw. Ed., Vol. 9, p. 638, 1843; figured by Kiener, Sp^c. Gen. Icon. Coq. Viv., Vol. 7, Triton, p. 45, pi. 16, figs. 1, 1842; also figured by Cossmann, loc. cit., text fig. 8; Recent, "Amerique merid- ionale," ? Chile, etc. Shell rather high spired, not very heavy, the varices weak and irregular or not accentuated at all, the denticles on the inside of the outer lip obsolete or nearly obsolete, but the prominence near the top of the inner lip well developed. Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 737 This section is very close both to typical Ranella and to Priene. If Ranella should be considered a subgenus of Gyrineum coordinate with Monoplex or a subgenus of Mono- plex, then Priene could well be treated as a section coordinate with Fusitriton and Argobuccinum. Perhaps Priene should not be treated as more than a section anyway, and Fusitriton may not even be sectionally distinct from Priene. Ranella (Priene) cancellata (Lamarck) may be the proper name for oregonensis. Lamarck and Kiener reported it from South America and Tryon reported it doubtfully from Chile, etc., probably on their authority; but it is well known that the older records of occurrences have frequently been erroneous. One error might account for all the reports. Most of the published figures of " cancellatus" have been of North American specimens, and the figures by Kiener and Cossmann show no characters by which the "South American" specimens can be distinguished. The writers have seen no recent, authentic report of such a form from South America. If Lamarck's type actually came from the northern end of the Pacific instead of the southern, as would be shown by the failure to find the species in South America after extensive collecting, then oregonensis would almost certainly be a synonym; and even if it is truly a South American form, it may be conspecific with oregonensis, having migrated across the equator, perhaps during the glacial epoch. If the writers had been able to consult Lamarck's original figure, they should probably have used the name cancellata for the northern shells. Ranella (Priene) oregonensis (Redfield) Plate 27, Figure 12 ? Triton cancellatum Lamarck, 1816. Triton oregonense Redfield, Ann. Lye. Nat. Hist. New York, Vol. 4, p. 165, pi. 11, fig. 2, 1846. Fiisus oregonensis Say, Reeve, Conch. Icon., Vol. 4, Fmiis, pi. 16, figs. 61a, 616, 1848. "Fiisus cancellatus Lamarck," Reeve, Conch. Icon., Vol. 4, Fiisus, pi. 16, fig. 62, 1848. "Tritonium cancellatum Lamarck," Middendorff, Beitr. Mai. Ross., Vol. 1, Pt. 2, p. 164, pi. 3, figs. 1-4, 1849. Trilonium {Priene) oregonensis Redfield, Gabb, Geol. Surv. Calif., Palffio., Vol. 2, p. 73, 1868-9; Whiteaves, Ottawa Naturalist, Vol. 7, p. 136, 1893; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 286, pi. 6, fig. 1, 1903. "Triton (Priene) cancellatus Lamarck," Tryon, Man. Conch., Vol. 3, p. 34, pi. 16, figs. 164-167, pi. 17, figs. 170-172, 1881. Priene oregonensis Redfield, Cooper, 7th ,\nn. Rept. Calif. State Mineralogist, p. 261, 1888; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 44, 1916; Yokoyama, Journ. Fac. of Sci., Imper. Univ. Tokyo, Sect. 2, Vol. 1, pp. 130, 131, 1926. Priene {Fusitriton) oregonensis Redfield, Cossmann, Ess. Paleo. Coinp., Vol. 5, p. 109, pi. 5, fig. 2, 1903; Vol. 6, p. 124, pi. 9, fig. 7, 1904. Fusilriton oregonensis Redfield, Dall, Smithsonian Misc. CqU., Vol. 47, p. 129, 1904. Argobuccinum {Fusitriton) oregonense Redfield, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 56, 1909. Argobuccinum oregonensis Redfield, Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 239, 1916. Argobuccinum oregonense Redfield, Dall, Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 93 and table opposite, 1922; Philpott, Publ. Puget Sound Biol. Sta., Vol. 37, pp. 369-380, pis. 34-36, 1925. Argobuccinum (Fusitriton) oregonensis Redfield, Dall, U. S. Nat. Mus., Bull. 112, p. 141, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 15, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 242, pi. 37, figs. 1, 2, 3, 1927; WaterfaU, Univ. Cahf. Publ. Geol., Vol. 18, p. 78, 1929. Miocene: Miocene of Coos Bay, Oregon (Howe). Pliocene: Coos conglomerate of Fossil Point, Oregon (Dall); upper part of Wildcat series of Humboldt Coimty (Martin); Piu-isima formation of middle California (Martin); Pico formation near Ventura (WaterfaU); St. George Island, Pribilof group (Dall, 1919); Pliocene beds of Chichibu and Shinano; Shirado beds; Musashino; all Japan (Yokoyama); upper Pliocene of Fourth and Broad- way, Los Angeles (Moody); S. D. S. N. H. locality 218, upper Pliocene of Sulphur Canyon east of South Mountain, Ventura County (H. R. G.). 738 San Diego Society of Natural History [Memoirs Pleistocene: Common in the "Pliocene" of Deadman Island; rarer in lower San Pedro series of Deadman Island; occasionally found in upper San Pedro series of Deadman Island, San Pedro, and Crawfish George's (Arnold, 1903); lower San Pedro fauna of Nob Hill cut (T. S. Oldroyd); Santa Barbara (Cooper); southwest of Goleta, on Campbell Ranch, not common (U. S. G.); etc. Recent: From the line of floating ice in winter in Bering Sea near the Pribilof Islands, south on the west to the Okhotsk Sea and Japan, and on the east to San Nicolas Island, California; San Diego in deeper water (Dall, 1921). This is the well-known northern species with a coarse, hirsute epidermis and nu- merous low axial ribs. It usually does not have clearly developed opposite varices on the body whorl, but they are often present and sometimes very well developed on the whorls of the spire. Ranella (Priene) oregonensis (Redfield) variety angelensis (Arnold) Priene wegonensis Redfield, var. angelensis Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 532, pi. 50, fig. 11, 1907; Eldridge and Arnold, U. S. Geol. Surv., BuU. 309, pi. 40, fig. 11, 1907. Type specimen: In the U. S. National Museum, No. 164,975. Type locality: Third Street tunnel, Los Angeles, California, Pliocene. Pliocene: Third Street tunnel, Los Angeles (Arnold); lower Pliocene of Elsmere Canyon, Los Angeles County (Eldridge and Arnold). According to Arnold, the variety angelensis differs from the typical form by its longer, less recurved canal and much less pronounced sculpture. Recent specimens of the typical variety in the collections at Stanford University indicate a variation which may include Arnold's variety. Ranella (Priene) scotiaensis (Martin) Argobucdnum scotiaensis Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 192, pi. 21, fig. 3, August 6, 1914. Type specimen: In the collection at the University of California. Type locality: About % mile north of Scotia, in the east bank of the Eel River, Hum- boldt County, Pliocene. Pliocene: Wildcat series of Humboldt Coimty (Martin). This form is very close to oregonensis and may be better considered a doubtful variety. The allies of oregonensis have been overnamed. Ranella (Priene) amoldi (Martin) Argobucdnum amoldi Martin, Univ. Calif. Publ. Geol., Vol. 8, p. 192, pi. 21, figs. 4a, 46, August 6, 1914. Type specimen: In the collection at the University of California. Type locality: Mouth of Bear River, Humboldt County, upper Miocene, or possibly lower Pliocene. Miocene or Pliocene: Upper Miocene or lower Pliocene at the mouth of Bear River, Humboldt County, California (Martin). This Ranella belongs to the oregonensis clan. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 739 Ranella (Priene) cammani (Dall) Argobuccinum [Fusilrilon) cammani Dall, U. S. Geol. Surv., Prof. Paper 59, p. 55, pi. 4, fig. 11, April 2, 1909. Argobuccinum cammani Dall, Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 590, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916; Howe, Univ. Calif. Publ. Geol,, Vol. 14, p. 93 and table opposite, 1922. Type specimen: In the U. S. National Museum, No. 153,907. Type locality: Coos Bay, Oregon; Miocene. Miocene: Montesano formation, upper Miocene of Washington (Weaver); Empire formation, upper Miocene of Coos Bay, Oregon (Dall). Pliocene: Coos conglomerate, Coos Bay, Oregon (Howe). This species is strongly constricted at the sutures. The type is a very imperfect specimen. It has narrow, distant axial ribs and spiral sculpture, and unless its appear- ance has been disguised by weathering it may not belong to this group. Family CASSIDIDAE Genus CASSIS Scopoli, 1777 Cassis Scopoli, Introd. Hist. Natur., p. 393, 1777; Montfort, Conch. Syst., Vol. 2, p. 599, 1810; Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 59-61, 1909; Schenck, Univ. Calif. Publ. Geol., Vol. 16, pp. 72, 74, 1926; Wood- ring, Carnegie Inst., Publ. No. 385, p. 304, 1928. Type (by subsequent designation, Montfort, 1810), Buccinum cornutum Linnaeus, Syst. Nat., Ed. 10, p. 735, 1758. Shell large, heavy, stout ; spire very low, bearing at intervals heavy varices ; aperture long, nar- row, deeply emarginate at base, forming a short, strongly curved canal; siphonal fasciole high; inner and outer lips very thick ; columella and adjoining part of inner lip plicate ; interior of outer lip bearing heavy ridges or denticles; sculpture consisting of nodes and axial wrinkles. (After Woodring.) Dall (1909) has given the synonymy of this genus and later Schenck (1926) discussed the genus and Pacific coast species in a paper on the Family Cassididoe. The generic name Cassis was used by Martini in the second volume of the Conchylien Cabinet, which was apparently issued in parts, the part with Cassis dating from 1771, six years earlier than Scopoli. Martini used the name in the nominative singular, care- fully described the shell and animal, and recognized three subgeneric groups. While there seems to be little reason to neglect the properly established names in the early volumes of the important work by Martini and Chemnitz, until some definite ruling is made in regard to which names should be used and which should be ruled out, more is gained in nomenclatorial stabiUty by following the custom of the majority of living authors. If the genus is to be used as of Martini, the type will be Cassis glauca (Linnaeus) , designated by Children in 1823. ' This species is included in Martini's treatment of the group. Scopoli, who adopted Cassis from Klein, recognized two sub-groups, (1) "Apertura elliptica" and (2) "Apertura angustiore," in the second of which he included "Bucc. rufum, cornutum, etc. Linn." The last species was selected by Lamarck in 1799 as an example of the genus Cassis and definitely designated genotype by Montfort in 1810. ^ If Cassis Martini is adopted. Phalium Link, 1807, will become an exact synonym, as it has the same type. 740 San Diego Society of Natural History [Memoirs Subgenus CASSIS, s. s. Cassis (Cassis) subtuberosa Hanna Cassis s-ubtuberosa Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 444, pi. 20, fig. 8, pi. 29, figs. 2, 3, March 23, 1926. Cassis {Cassis) svbtiiberosa Hanna, Schenck, Univ. Calif. Piibl. Geol., Vol. 16, p. 7.5, pi. 12, figs. 2, 3, May 4, 1926. Type specimen: In the collection at the University of California, No. 31,275. Type locality: Alverson Canyon, Coyote Mountain, Imperial County. Pliocene: At the type locality (Hanna). Subgenus LEVENIA Gray, 1847 Levenia Gray, Proe. Zool. Soc. London for 1847, p. 137, November, 1847; Dall, II. S. Geol. Surv., Prof. Paper 59, p. 60, 1909. Type (by original designation), "Cassis coarctatum Gray" = Cassis coarctata Sowerby. The shells of this section have narrow apertures contracted in the middle, and the outer lip is not varicose. Cassis (Levenia) coarctata Sowerby Cassis coarctata Sowerby, Cat. Shells Tankerville, Appendix, p. xxi, 1825; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Cassis coarctata Wood, Index Testae, Suppl., pi. 4, fig. 5, 1828. Cassis coarctata Gray, Reeve, Conch. Icon., Vol. 5, Cassis, pi. 6, fig. 14, 1848; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 272, Cassidids; pi. 2, fig. 52, 1885. Cassis (Levenia) coarctata Sowerby, Schenck, Univ. Calif. Publ. Geol., Vol. 16, p. 76, pi. 12, fig. 4, 1926. ? Pliocene: Monserrate Island, Gulf of California, Mexico, "probably Pliocene" (Hanna and Hertlein). Pleistocene: Escondido Bay, Oaxaca, Mexico (see Schenck, 1926; in Palmer collection). Recent: West coast of Mexico, Panama, and Galapagos Islands. Sowerby was uncertain of the habitat of this shell, but believed it came from New Zealand. It is well figured by Reeve, and Schenck has recently figured a specimen in the Oldroyd Collection at Stanford University. Family TONNIDAE As the genus Dolium Lamarck, 1799, falls as a synonym of Tonna Brunnich, 1771, or in any case is of later date, the family name must become Tonnidce. Genus MALEA Valenciennes, 1832 Malea Valenciennes, in Humboldt and Bonpland, Voj'. Reg. Equinox. Nouv. Cont., Recueil Obser. Zool. Anat., Comp., Vol. 2, p. 324, 1S32, fide Woodring, 1928; Herrmannsen, Ind. Gen. Malac, Vol. 2, p. 13, 1847; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 72, 1909; Woodring, Carnegie Inst., Publ. No. 385, p. 310, 1928. Type (by subsequent designation, Herrmannsen, 1847), Malea latilabris Valen- ciennes ( = Cassis ringens Swainson) . Shell reaching a large size, subglobose, spire low. Nucleus naticoid, consisting of between three and four whorls, the later ones enlarging rapidly. Aperture large, wide, deeply emarginate at base, formijig a wide, short canal. Siphonal fasciole mflated. Inner lip detached on adult shells at base. Columella bearing a heavy basal twist on which several folds are imposed on iimer lip. Middle or parietal wall bearing two or three heavy ridges. Outer lip varicose, resorbed as gro\vt:h continues, outer edge frilled, uuier edge heavily ridged. Sculpture consistmg of broad spiral bands. (Woodring.) This genus lived in the Miocene and Pliocene of the Mediterranean region, was well represented in the Caribbean Miocene, and occurs in the Recent fauna of the Pacific. "Dolium" jamaice7ise Trechmann,^ of the Yellow Limestone of Jamaica, middle Eocene, may be a Malea.- ' Geol. Mag., Vol. 60. p. 356, pi. 18. fig. 7, 1923. ! Fide Woodring. op. cit.. p. 311, 1928. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 741 Woodring (1928) designated Buccinum perdix Linnaeus as type of both Cadus Bolten' and Cadium Link,^ which makes those two names synonyms of Tonna Brunnich.' Woodring pointed out that Suter cited Buccinum galea Linnseus as the type of Tonna but that he was unable to discover who first assigned species to Tonna and what species, therefore, are available as type. If Suter's type designation is valid, then Dolium Lamarck, 1801,^ becomes an exact synonym of Tonna, for they have the same type. Malea ringens (Swainson) Cassis ringens Swainson, Bligh Cat., Append., p. 4, 1822, reprinted in Swainson's "Exotic Conchology," Ed. 2, edited by S. Hanley. Dolium latilabre Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 7, "Tonne," p. 14, pi. 4, fig. 6, 1835, young shell. Dolium ringens Swainson, Reeve, Conch. Icon., Vol. .5, Dolium, pi. 4, fig. 5, 1848. Malea ringens Swainson, in Sowerby, MabiUe, BuU. Soci^te Philomathique de Paris, Ser. 8, Vol. 7, p. 59, 1895. Malea ringens Swainson, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 227, 1909; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 450, 1926. Pliocene:^ Coyote Mountain, Imperial County (Hanna); numerous specimens from vicinity of Alverson Canyon, Coyote Mountain (coll. by E. H. Quayle and U. S. G.). Recent: Gulf of California, Mexico, South to Paita, Peru, and Galapagos Islands (Dall, 1909). This species occurs rather abundantly in some localities in the Coyote Mountain region of western Imperial County, particularly in the fossiliferous beds about a half mile north of the mouth and just to the west of Alverson Canyon. In the Los Angeles Museum there is a specimen collected by Charles Sternberg at Alverson Canyon which measures 115 millimeters in axial length and nearly as much in diameter. The small Recent specimens do not show the strong ridges on the inner lip developed by mature individuals. Kiener figured a juvenile shell. Malea camura Guppy,^ of the lower and middle Miocene of several Caribbean locali- ties, is a closely related but smaller and less shouldered form. Family FICIDAE Genus FICUS (Martini, 1777) Bolten, 1798 Ficns Klein, pre-Linnaean. Ficus Martini, Neues Syst. Conch. Cab., Vol. 3, pp. 3, 21, etc., 1777, type (by absolute tautonymy) Murex ficus Linnaeus (cited p. 22), this reference usually not accepted because Martini and Chermiitz, although using a binary system of nomenclature with genera (Geschlechte) and species (Gattungen), are not consistently binomial in the Linnaean sense. Rapa Martini, loc. cit., p. 21. Ficus Bolten, Mus. Boltenianum, p. 148, 1798, type (by absolute tautonymy) Bulla ficus Gmehn = Murex ficus hin- naeus; Dall, Prof. Paper 59, U. S. Geol. Survey, p. 74, 1909. Pyrula Lamarck, "Prodr.," Mem. Soc. Hist. Nat., Paris, Ser. 1, Vol. 1, p. 73, 1799, type (by monotypy) Bulla ficus Linnaeus; Tryon, Man. Conch., Vol. 7, pp. 258, 265, 1885; Smith, Proc. Acad. Nat. Sci. Phila., pp. 208-219, pi. 17, 1907; not Pyrula Reeve, Conch. Icon., Vol. 4, 1847, nor Sowerby, Thes. Conch., Vol. 4, 1880. ' Mus. Boltenianum. Pt. 2, p. 150, 1798. 2 Beschr. Natur.-Samml. Rostock, p. 113, 1807. ^ Zoologiae Fundamenta, p. 248, 1771, genus without species. * Syst. Anim. s. Vert., p. 79, only species listed, Buccinum galea Linnffius. Martini (Neues Syst. Conch. Cab., Vol. 3, p. 390, 1777) used Dolium in a generic sense but his work is not consistently binomial. If Dolium should be accepted as of Martini, 1777. then the type would be "Buccinum^' dolium Linnteiis. by absolute tautonomy (cited as a synonym by Martini on p. 400). Dolium of the Mu.seum Calonnianum (p. 19, 1797) is considered invalid and its use in the second edition of Brown's Civil and Natural History of Jamaica, 1789, is invalidated by suspension of the rules (see Opinion 89, Inter. Comm. Zool. Nomenclature). * Since this paper went to press W. P. Woodring has expressed the opinion that the Coyote Mt. beds are Miocene in age (oral communi- cation) . * Quart. Journ. Geol. Soc. London, Vol. 22, p. 287, pi. 17, fig. 9. 1866; also figured and discussed by Woodring, C-^rnegie Inst.. Publ. No. 385. p. 311, pi. 20, figs. 7, 8, 1928. 742 San Diego Society of Natural History [Memoirs Pirula Montfort, Conch. Syst., Vol. 2, p. 486, 1810, tjTDe (by original designation, etc.) Murex ficus Linnaeus. Ficvla Swaicson, Treat. Make, pp. 85, 307, 1840, species included, ficus, Encyclopedic Methodique, pi. 4.31, fig. 1, and caudata Swainson, illustrated in the Encyclopedic Methodique, pi. 436, figs. 1&, Ic; Reeve, Conch. Icon., Vol. 4, 1 pi., 1847; Sowerby, Thes. Conch., Vol. 4, 1880. Sycotypus Browne, Morch, Cat. Yoldi., p. 110, 1852, species included, ficus Linnaeus, ficoides Lamarck, dussumieri Valenciennes, and reiiadalus Lamarck. Pirvla Lamarck emended, Cossmarm, Ess. Palfio. Comp., Vol. 5, p. 140, 1903. Type (by absolute tautonymy), Murex ficus Linnaeus, Recent, Indian Ocean. Shell of medium size, thin, with a very low spire or in some cases no spire; body whorl large, fig-shaped, with a broad, midefined anterior canal ; axial and spiral sculpture of fine hues or cords in both directions. Geologic range: Eocene to Recent. Distribution: Tropical and subtemperate waters of all oceans. Subgenus FICUS, s. s. Shell very thin, outline of body whorl smoothly rounded, without angulations or nodes, anterior canal fairly long, wide, straight or nearly straight. The species of this subgenus are few and look very much alike. It is not improbable that some of the middle Tertiary forms will be recognized as living species. Ficus (Ficus) modesta (Conrad) Pyrvhi modesta Conrad, Amer. Journ. Sci., Ser. 2, Vol. 5 (whole no. Vol. .55), p. 433, fig. 12, 1848, reprinted by Dall, Prof. Paper 59, U. S. Geol. Survey, p. 151, fig. 12, 1909. Ficus pyriformis Gabb, Geol. Surv. Calif., Palao., Vol. 2, pp. 48, 77, pi. 14, fig. 4, 1868-69; Arnold, Bull. 396, U. S. Geol. Survey, p. 18, January 15, 1910; English, Univ. Calif. Publ. Geol., Vol. 8, p. 246, pi. 25, fig. 1, 1914. Ficus modestus Conrad, Dall, Prof. Paper 59, U. S. Geol. Survey, p. 74, 1909; English, Univ. Calif. Publ. Geol., Vol. 8, p. 246, 1914; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 372, pi. 31, fig. 2, 1926. Shell rather elongate, spire low, roimded, sculpture of a moderate number (very roughly 25) of narrow spiral cords, with lesser mtercalaries, growth lines about as strong as the finest spiral Imes. Type specimens: Of modesta, lost; of pyriformis, No. 4325, at the Academy of Natural Sciences, Philadelphia. Type localities: Of modesta, Oligocene or Miocene of Oregon; of pyriformis, Oligocene or Miocene, near Martinez, middle California. Oligocene: San Ramon formation, south of Martinez, Contra Costa County (type locality of pyriformis). Miocene: Columbia River, near Astoria, Oregon (possibly Oligocene); Temblor formation of Coalinga region and in the Santa Cruz Quadrangle (Arnold). The synonymy of this species was recognized by Stewart. Both Gabb and Stewart mention that it resembles the living F. dussumieri (Valenciennes in Kiener) ;' and it has practically the same shape as that species, though differing somewhat in the details of the sculpture. It seems to have a larger number of accentuated spirals, with fewer minor ones; but the sculpture of the living species must vary considerably, and the writers do not know whether modesta is really separable from dussumieri or even from reticu- lata (Lamarck). ' Pyrula dussumieri Viilenciennes in Kiener, Sp^c. Gl5n. Icon. Coq. Viv.. Vol. 6, Pyrule. p. 25, pi. 11, 1840. Li\'ing off coasts of China. VoLtiME I ] Pliocene and Pleistocene Mollusca of California 743 Ficus (Ficus) ventricosa (Sowerby) Ficus temiis magna caricellala Martini, Neues Syst. Conch. Cab., Vol. 3, p. 21, pi. 66, fig. 733, 1777. Pyrula ventricosa Sowerby, Cat. Shells Coll. Earl of TankerviUe, Appendix, p. xvi, 1825; Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 6, Pyrule, p. 27, pi. 12, figs. 2, 1840. Bidla decussata Wood, Suppl. Index Test., fig. 9, 1828. Ficula decussata Wood, Reeve, Conch. Icon., Vol. 4, Ficula, pi. 1, species 3, 1847; not Sowerby, Thes. Conch., Vol. 4, p. 110, pi. 423, figs. 1, 2, 3, 1880 {fide Tryon). "Ficula reticulata Lamarck" Sowerby, op. cil., p. 110, figs. 6, 7, 1880. Fyrula decussata Wood, Tryon, Man. Conch., Vol. 7, p. 266, pi. 6, fig. 34, 1885; Mabille, Bull. Sec. Phil. Paris, Ser. 8, Vol. 7, p. 60, 1895. Ficus decussatus Wood, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 449, pi. 21, fig. 9, 1926. Shell not particularly elongate, spire very low, a few (10 or 12) .spiral cords strongly accentuated, grading downward into more numerous, weaker spiral threads, a few minor threads in the interspaces. Pliocene: Coyote Mt., Imperial Co., California (Hanna). Pleistocene: Lower Quaternary of Magdalena Bay, Lower California (Jordan). Living: Cape San Lucas, Lower California, to Ecuador. This species is distinguished from modesta by its very low spire and by the accentu- ated spiral cords being fewer and more distant. Subgenus TROPHOSYCON Cooper, 1894 Trophosycon Cooper, Bull. No. 4, Calif. St. Mining Bureau, p. 53, 1894; Dall, Prof. Paper 59, U. S. Geol. Survey, p. 75, 1909; English, Univ. Calif. Publ. Geol., Vol. 8, p. 245, 1914. Type (by monotj'py), Agasoma ? (Trophosycon) kernianum Cooper = Sycotypus ocoyanus Conrad. Shell when young like that of a typical Ficus; when adult with two more or less strongly nodose angulations, an upper and a lower, and with a more or less recurved canal. Geologic distribution: Lower Miocene to lower Pliocene in California, middle Miocene of Washington, upper Miocene of Oregon. Cooper placed this subgenus doubtfully under Agasoma Gabb (as then used, sensu lato); Dall classed it under Ficus; and EngUsh considered it a separate genus, though noting that there is a "probable genetic relationship" between Ficus and Trophosycon. Since Trophosycon appears to be a local off-shoot clearly connected in many ways with the main Ficus stock, and since nodose species of Ficus are recorded from the European Tertiary, it is not thought desirable to obscure the relationship by calling Trophosycon a distinct genus. Ficus (Trophosycon) ocoyana (Conrad) Plate 30, Figures 3, 7, 8a, 8b, 11 Sycotypus ocoyanus Conrad, U. S. House of Representatives, Doc. No. 129, p. 19, 1855, reprinted by Dall, Prof. Paper 59, U. S. Geol. Survey, p. 170, 1909; Reports of U. S. Pacific Railroad Explorations and Surveys, Vol. 5, pt. 2, appendix, p. 329, pi. 7, figs. 72, 72a, Washington, 1856, reprinted by W. P. Blake, New York, 1858, (in these references the spelling of the generic name varies, probably through typographic errors); Cooper, Bull. No. 4, Calif. St. Mining Bureau, p. 54, 1894. "Unknown" casts, Conrad, Reports of U. S. Pacific Railroad Explorations and Surveys, Vol. 5, pt. 2, appendix, pi. 7, figs. 64, 64a, 65, 65o, Washington, 1S56, reprinted with explanation of plates by W. P. Blake, New York, 18.58. Ficus nodiferus Gabb, Geol. Sur\-. Calif., Palseo., Vol. 2, pt. 2, p. 48, pt. 3, p. 77, jjI. 14, fig. 5, 1868-9, in part only; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 166, 175, 179, 1912; Vol. 9, p. 160 only, 1919; not Pyrula nodifera Binkhorst, Mon. Gast. Ceph. Craie Sup. Limbourg, p. 67, pi. 5a-3, fig. 11, 1861. Ficus ocoyanus Conrad, Gabb, Geol. Surv. Calif., Pateo., Vol. 2, pt. 3, p. 113, 1S68-9; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 175, 1912. 744 San Diego Society of Natural History [Memoirs Ficula nodifera Gabb, Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 240, 1888. Ficula ocoyana Conrad, Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 240, 1888. Agasoma ? (Trophosycon) kemianum Cooper, BuU. No. 4, Calif. St. Mining Bureau, p. 53, pi. 3, fig. 52, 1894. Agasoma kernianum Cooper, F. M. Anderson, Proc. Calif. Acad. Sei., Ser. 3, Vol. 2, pp. 176, 185, 188, 1905; Arnold, Prof. Paper 47, U. S. Geol. Survey, pp. 19, 73, 78, 83, 84, 1906; Eldridge and Arnold, Bull. 309, U. S. Geol. Survey, p. 147 questionably identified, 1907; Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 353, pi. 34, fig. 2, August, 1908; F. M. Anderson, Proe. Calif. Acad. Sci., Ser. 3, Vol. 3, pp. 19, 23, 25, October, 1908; Branner, Newsom, and Arnold, Folio 163 (Santa Cruz), U. S. Geol. Survey, p. 4, pi. 2, fig. 40, 1909; Arnold, Bull. 396, II. S. Geol. Survey, p. 18, January 15, 1910; Arnold and R. Anderson, Bull. 398, pp. 85, 86, 1910; F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 100, 101, 1911; McLaughlin and Waring, Folio accom- panying Bull. No. 69, Calif. St. Mining Bureau, pi. 1, fig. 30, 1914. Agasoma sianfordensis Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 384 in part, not the San Diego specimen, pi. 35, fig. 5, 1908; Branner, Newsom, and Arnold, Folio 163 (Santa Cruz), U. S. Geol. Survey, p. 4, pi. 2, fig. 54, (same figure), 1909. Finis kernianvs Cooper, Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 166, 175, 179, April, 1912; Martin, Univ. Calif. Publ. Geol., Vol. 7, p. 148, December, 1912; Arnold and Hannibal, Proc. Amer. Phil. Soc, Vol. 52, p. 586, 1913; Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 43, 1914; Smith, Vol. 9, p. 160, 1919. Ficus stanfordensis Arnold, Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 166, 175, 179, 1912; Arnold and Hannibal, Proc. Amer. PhU. Soc, Vol. 52, p. 588, 1913; Trask, Univ. Calif. Publ. Geol., Vol. 13, pp. 141, 143, 144, 145, 1922. Trophosycxm keniianvm Cooper, English, Univ. Calif. Publ. Geol., Vol. 8, p. 248, pi. 24, figs. 4, 5, 6, 1914; Hertlein and Crickmay, Proc. Amer. Phil. Soc, Vol. 64, p. 260, 1925. Trophosycon stanfordense (Arnold), English, Univ. Calif. Publ. Geol., Vol. 8, p. 249, pi. 24, figs. 2, 3, 1914. ? "Ficus oregonensis Conrad," Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 30, 1916, not of Conrad (see next reference). "Ficus (Trophosycon) oregonensis (Conrad)," Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, pp. 373-5 in part, (pi. 31, figs. 8, 8a ?), 1926, not "Ficus (Trophosycon)" oregonensis Conrad, Dall, Prof. Paper 59, U. S. Geol. Survey, p. 75, 1909, nor "Trophosycon" oregonense (Conrad), English, Univ. Calif. Publ. Geol., Vol. 8, p. 250, 1914, the last two of which refer to Fusus oregonensis Conrad, -Amer. Journ. Sci., Ser. 2, Vol. 5, p. 432, fig. 13, 1848, reprinted by Dall, op. cit., p. 150, fig. 13, 1909, which may be an Agasoma (sensu lata) but is certainly not a Ficus. A Trophosycon of comparatively small or moderate size, shell of medium thickness, spire low, apical angle varying from about 105° to 115°; whorls five, body whorl large, angulated along two spiral rows of nodes, the upper row about one-fifth of the way from the suture to the anterior ex- tremity as measured aroimd the whorl, the lower about half way, shell wall between the nodes smoothly roimded and only a Uttle more strongly curved, eight or nine nodes to a whorl on each angulation, the lower row usually alternating with the upper, nodes characteristically single and roimded like the end of a twig which has been broken off not far from the branch, but occasionally with a lesser auxiliary node on the next main spiral line above or below, the two pomts coalescing vertically and forming a double-headed elongate node, also very rarely a third small knob on the other side of the main node from the second; body whorl also sculptured ■with distinct but usually fine, low, roimded, spiral cords, of the heaviest of which there are about eight below the lower angle, one on each of the angles, three between the angles and four above the upper angle, also between each of the main spirals a smaller intercalary, which sometimes, however, becomes ahnost as promi- nent as the primaries, and between each primary and the secondary next to it a still fainter tertiary, the whole surface covered with somewhat irregular growth lines, usually about equal in strength to the spiral sculpture; anterior canal moderately long, broad, smoothly but decidedly recurved, columella smooth, curving in strongly below the lower angle and then out again, inner lip covered with a fairly thick deposit of callus which rounds over the lower row of nodes and spreads out over the upper angle of the preceding whorl, remaining ex]30sed there in an irregular spiral strip above the suture; sutures tangential at the upper angle of the preceding whorl, or abutting shghtly below it. Dimensions (from EngUsh): Altitude 62 mm.; diameter of body whorl 45nim. ; length of aperture 54 mm., width of aperture 23 mm.; width of canal 15 mm., depth 5 mm., length about 15 mm. Type specimens : Of ocoyana, drawn in the field and subsequently lost ; of nodifera, No. 27,824 in the Whitney Collection at the Museum of Comparative Zoology, Harvard University; of kerniana, whereabouts unknown; of stanfordensis, No. 425 at Stanford University. Type localities: Of ocoyana, Miocene of Ocoya ( = Poso) Creek, near Barker's Ranch, Kern Co.; of nodifera, Miocene at Griswold's, between San Juan and New Volume I ] PlIOCENE AND PLEISTOCENE MoLLTJSCA OF CALIFORNIA 745 Idria, Monterey Co. {fide Stewart); of kerniana, Miocene of Barker's Ranch; of stan- fordensis, two and one-half miles south of Mayfield, Santa Clara Co. Miocene: Monterey-Temblor, middle Miocene, of California, 'Oregon, and Washington. Young specimens are more like typical Ficus, with smaller nodes or even no nodes, straighter, more elongate canal, and sculpture of sharp cords running in both directions. Casts are impossible to distinguish from casts of small specimens of the Pliocene variety ruginodosa. The nodes are represented by low bumps of varying prominence along the angulations, usually more or less rounded, but sometimes vertically elongate. The outlines show the strong incurving of the columella, and, where the nodes do not interfere, the nearly vertical section of the wall between the two angles. On casts of very young specimens the nodes do not show through at all, as in Conrad's type. The type of Agasoma stanfordensis Arnold has been found among the fossils stored at Stanford University and is now No. 425 in the type collection. It is a very poor cast, showing nothing but the general shape, the somewhat worn nodose impressions along the upper angle, and faint undulations on the lower. The nodes are small, and those on the side which Arnold figures have an unnatural, pinched, elongate appearance; but the shape of the nodes on the other side of the specimen is more normal and indicates that the weathered aspect is misleading. The lower part of the columella, the anterior canal, and the outer lip are missing. There is nothing on the type specimen by which it can be distinguished from the common species generally known as Ficus herniana Cooper ( = Ficus ocoyana), or, indeed, from the Pliocene forms usually known as Ficus nodifera Gabb. Arnold must have based his distinction from Agasoma kernianum largely on the characters of a specimen from the PUocene of San Diego, upon which some of the external sculpture appears to have been preserved, for he speaks of the "usually much larger size" and the "details of the spiral sculpture . . . coarser." The San Diego specimen is not as Arnold supposed the same variety, but belongs to a form of the new variety ruginodosa. Since the type, the only known specimen from the type locaUty "two and one-half miles south of Mayfield," Santa Cruz Quadrangle, was so poorly preserved, Mr. Lionel Wiedey and the writers revisited the type locality to look for more material. Another fragmentary cast was obtained, and although it is even more poorly preserved than the type, it shows a slightly lower spire and more gently rounded nodes on the upper angulation, which is characteristic of another common variation of ocoyana and strengthens the conclusion that Ficus stanfordensis is an indistinguishable synonym. The other species collected with Ficus stanfordensis at its type locality include Agasoma (Bruclarkia) sp., Pecten andersoni Arnold, and Area cf. montereyana Osmont, which indicate that the beds which Ai-nold considered upper Miocene in this locality are of Monterey-Temblor age; or, in other words, of the same horizon as that from which the type and many other specimens of Ficus kerniana came, and also, according to Stewart, the type of Ficus nodifera (Gabb). It may be worth mentioning that in Smith's paper on the Miocene fossils of California (1912) stanfordensis has the same dis- tribution as both nodifera and kerniana. A more nearly complete cast in the Stanford collection from the Santa Cruz Quadrangle labeled stanfordensis is of typical kerniana ( = ocoyana) shape. There is, therefore, unless important new evidence of a contrary nature is brought to light, no reason whatsoever for retaining the name stanfordensis, which has always represented among paleontologists a troublesome unknown quantity. The cast of a very small specimen from the Miocene of Ocoya ( = Poso) Creek that was named from Blake's drawings by Conrad Sycotypus ocoyanus, although showing very little that is of value for the identification of other specimens, has at least the low 746 San Diego Society of Natural History [ Memoirs spire and general form of Ficus, and the two strong angulations and incurved columella of the subgenus Trophosycon. F. M. Anderson, who has carefully studied the Poso Creek section, states that Blake's collecting locality was almost surely on Pyramid Hill at a horizon which Anderson terms Zone A. Barker's Ranch, the type locality of Ficus kerniana (Cooper), is not far distant but is at a slightly higher horizon, Zone B. Good specimens of kerniana are, however, common at both localities, and the "unknown" casts from Blake's locality figured but not named by Conrad in the same publication have been recognized as kerniana by English. Moreover, young specimens of kerniana from Pyramid Hill, as well as some adult casts including a specimen from Griswold's in the collection at Stanford University, show a strong resemblance to the rather peculiar shape of Blake's drawing. Since Ficus stanfordensis has been shown to be a synonym, and since there is no reason to believe that the Miocene specimens assigned by various authors to Ficus nodifera are distinct, there are no other species of Trophosycon known from these localities, and Conrad's species, which has long been unidentifiable, can be no other than what has generally been known as Ficus kerniana. The only other species thought to occur in the lower or middle Miocene of the Pacific coast is Ficus clallamensis Weaver, a Washington species from the Clallam formation, "upper middle Miocene," which is also found in the Santa Margarita formation, upper Miocene, of California, and is questionably identified from the middle Miocene of Orange County, California. Blake's original specimen of ocoyana could hardly have been clallamensis, for no adult specimen like clallamensis has ever been reported from that locality, and the whorls in Blake's drawings are not broad enough above the upper angle. Nor could it be Ficus clallamensis variety nodibulbosa, which comes from the upper Miocene of California, because of the strongly incurved columella shown in Blake's drawing. It is unfortunate to have to discard so well known and well characterized a name as kerniana, but it is the writers' belief that it will be less difficult to do so now than later. The identifications of Fusus oregonensis Conrad as a Ficus by Dall and Stewart were based on the supposition that Conrad's figure and description were very poor; but more recent collections from Conrad's locality include specimens of a species entirely different from the Trophosycons, and these specimens agree very closely with Conrad's illustration and description. Therefore, the middle Miocene Trophosycon cannot take the name of oregonensis Conrad. Variety ocoyana, s. s. Shell relatively small, sho'sving adult characters when less than 40 mm. in altitude, sculpture fine, nodes usually single and romided. Ficus (Trophosycon) ocoyana (Conrad) variety ruginodosa, new variety Plate 29, Figures 2a, 2b; Plate 30, Figures 5, 10a, 106 Ficus nodiferns Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, pp. 48, 77, pi. 14, fig. 5, 1868-9, in part only, not the tjqie; Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 203, 1916; Vol. 10, pp. 212, 213, 221, 1917; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, p. 153 only, 1919; not Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, pp. 166, 175, 179, 1912; not Pyrula (= Ficus) nodifera Binkhorst, Mon. Gast. Ceph. Craie Sup. Limbourg, p. 67, pi. Vo. 3, fig. 11, 1861. Agasoma stanfordensis Arnold, Proc. 11. S. Nat. Mus., Vol. 34, p. 384, in part (not the type), 1908. Trophosycon nodiferum (Gabb), English, Univ. Calif. Publ. Geol., Vol. 8, pp. 211, 247, pi. 25, figs. 2, 4, 1914; Kew, Bull. 753, U. S. Geol. Survey, p. 78, 1924. "Ficus (Trophosycon) oregonensis Conrad," Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, pp. 373-5 in part, (pi. 31, figs. 8, 8a?), 1926, not of Conrad (see synonjTuy under Ficus ocoyana). Volume I ] PLIOCENE AND PLEISTOCENE MoLLTJSCA OF CALIFORNIA 747 Ficus "nodifer" (Gabb), Stewart, op. cit., p. 374, in part, emended name for Ficus nodiferus Gabb. (Since Gabb originally used the name as nodiferus, it does not seem advisable to change the masculine form to "nodifer," even though the nominative singular masculine of the adjective which means "bearing nodes" lack the termination. We cannot be sure that Gabb did not mean ii,odi + ferus or "wild with nodes." The new species name, ruginodosa is compounded with a different adjective in order to avoid the recurrence of this question in case the species should be assigned to a masculine genus.) A Trophosycon of very large size, shell of medium thickness, spire low, apical angle varying from about 105° to 115° (but if the body whorl is included m the measurement, the angle becomes consid- erably larger, — that is, the compound surface formed by the upper parts of all the whorls becomes concave in adult specimens) ; whorls five, body whorl large, angulated along two usually compound spiral rows of nodes, the upper row lying between a quarter and a fifth of the distance from the suture to the anterior extremity as measured aromid the whorl, the lower about half way, the shell wall between the nodes strongly curved around an angle of about 110° at the upper shoulder, and 140° at the lower ; nijie or ten nodes to a whorl on each angulation, the smaller number on smaller speci- mens; additional sculpture on the body whorl sunilar in pattern to that on typical Ficus ocoyana, but much coarser, consistmg of primary, secondary, tertiary, and also quaternary cords, all but the primaries arising by intercalation between the earlier lines of sculpture, the number of primaries above the upper and below the lower angulations bemg, however, difficult to coimt because of the complication of the pattern and because all of the primaries are no longer regularly emphasized, only the three nearest to each angle standing out clearly above the others, these three being some- times tremendously accentuated, bmiching up periochcally on large specimens into triple nodes, gro\\'th lines present but weak in comparison; anterior canal moderately long, broad, smoothly but decidedly recurved in the adult, columella smooth, in mature specimens curving in strongly below the lower angle and then twistmg out agam and over, umer Up covered with a fairly thick deposit of callus, which partially rounds over the lower row of nodes and which spreads out over the upper angle of the preceding whorl and remains exposed there in an irregular spiral strip above the suture, outer lip simple, tangential at the upper angle or abutting slightly below it. Dimensions of type : Altitude 110 mm.; diameter of body whorl 80 mm.; height of spire above body whorl 17 mm.; long axis of aperture (exclusive of canal) 70 mm.; length of canal (estimated) 30 mm.; width of canal 20 mm., depth 8 mm. Type specimen: No. 3 in the type collection of the San Diego Society of Natural History. Type locality: No. 209 S. D. S. N. H., basal Pliocene of Elsmere Canyon, Los Angeles County. Lower Pliocene: Elsmere Canyon. ? Middle Pliocene: San Diego. Young specimens are very different in shape, having a columella which is in most cases nearly as straight as that of Ficus clallamensis variety nodibulbosa, usually bearing little resemblance to specimens of typical Ficus ocoyana of the same size. One specimen in the Stanford collection from Elsmere Canyon has preserved its youthful characters up to a size of 70 mm., but this is probably unusual. Young specimens are more elongate; but care must be taken in judging the relative proportions of any specimens which have defective body whorls, for they always give an erroneous appearance of being unusually elongate, as is shown by the shell-covered part of the type of the variety contignata, if one imagines the other part removed. The question of nomenclature arises here again. The preoccupation of the name nodifera by Binkhorst, whose work was published eight years earlier than Gabb's, means that the form from Elsmere Canyon, even if properly identified as Gabb's nodi- fera, probably requires a new name. Stewart, however, has inferred from the matrix of Gabb's type (the specimen which he figures, — loc. cit.) that it is the specimen mentioned by Gabb as coming from the Miocene of Griswold's, in which case the Pliocene form has never received a name. The soundness of this inference is questioned: because Gabb states that "the best preserved specimen yet obtained was found by Mr. Frank E. Brown in the rich fossiliferous Pliocene sandstones of the San Fernando Pass, at the west end 748 San Diego Society of Natural History | Memoirs of San Gabriel Mountains," and it is to be supposed that Gabb would use the best specimen for his description and illustration; also because the type figured by Stewart retains a large part of the shell, as is commonly the rule with Elsmere Canyon specimens, whereas the other specimen mentioned by Stewart as part of the type material is a cast like the only specimen of Ficus from Griswold's that the writers have seen; because there are several kinds of matrix to be found in the fossiliferous beds of Elsmere Canyon; and because Stewart's figure of the type, although not characteristic, looks more like an Elsmere Canyon specimen than one from the Miocene. It is fortunate that the pre- occupation of the name will eliminate the necessity of deciding this question. The point is discussed here merely because Stewart's figiu'e, if its assignment to the Miocene were not questioned, might cause difficulty in distinguisliing the varieties. To avoid this point, the form ruginodosa is described as entirely new, not as a new name for nodifera Gabb. The variety ruginodosa has when young, or when about the average size of Ficus ocoyana, very rudimentary nodes, nodes which are usually smaller than on the latter species and are so inconspicuous that some specimens have been mistaken for a typical Ficus. At that stage, the vertical striations are about equal in strength to the secondary spirals. The nodes on the upper angulation are usually single, being a little stronger and appearing a little earlier than the nodes on the lower angulations, which are usually triple and develop at first merely as disconnected flexuous accentuations of the three heavy primary spirals. The lower angulation is hardly recognizable as such until the shell grows larger than most full-grown specimens of ocoyana. The adult is only moder- ately nodose for its size, but the spirals are strongly rugose; hence the name ruginodosa, given to stress the rugosity and to recall Gabb's name. The variety ruginodosa can be distinguished from typical ocoyana when adult by its much larger size, by the three strong rugose spirals and the three rows of small nodes on the lower angle, and by the generally much more rugose nature of the spiral sculpture. Specimens of ocoyana from Barker's Ranch which are not half the size of the type of ruginodosa show gerontic characters such as extreme irregularity of growth lines and almost complete loss of nodes on the last part of the body whorl, indicating that the difference in size is a useful means of separating the Pliocene from the Barker's Ranch variety. The young of ruginodosa, moreover, are quite different from the adult of typical ocoyana to which they compare in size; and their characters suggest that ruginodosa may be derived from Ficus clallamensis variety nodibulbosa instead of from Ficus ocoyana, and that the similarity in shape of the adult of ruginodosa to the adult of ocoyana might be due to parallel development. The adult of ruginodosa is distin- guishable from nodibulbosa by its stronger nodes and angulations and its more differ- entiated spiral sculpture; the young by more deUcate and more distinctly differentiated spiral striation, relatively stronger vertical cords, and usually less elongate upper nodes. The typical Ficus clallamensis is difficult to distinguish, because nothing certain is known of the shell. It has a low spire, broad upper surface, more rounded angles, a greater ratio of diameter of body whorl to altitude, and if the Orange County specimen men- tioned above as possibly a clallamensis can be trusted, a less complicated pattern of spiral sculpture. The very young of ruginodosa are distinguished only by their incipient nodes from Ficus modesta (Conrad), a typical Ficus. The variety ruginodosa is definitely known only from the lower Pico (lower Pliocene) of Elsmere Canyon, Los Angeles County, California. The type came from the center of a large concretion at S. D. S. N. H. locality 309. This variety is less common than the variety contignata. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 749 Ficus (Trophosycon) ocoyana (Conrad) variety contignata, new variety Plate 29, Figures la, lb; Plate 30, Figures 1, 2, 4, 9a, 9b Dimensions of the type: altitude 92 mm. (canal defective, probably more than 10 mm. broken off); diameter of body whorl 83 mm.; height of spire 12 mm. Type specimen: No. 4 in the type collection of the San Diego Society of Natural History. Type locality: No. 203 S. D. S. N. H., Elsmere Canyon, Los Angeles Co. L. Pliocene: Elsmere Canyon localities, also loc. 227, south of Humphreys Station; Jacalitos formation, middle California (Nomland, and in the Stanford collection). L. or M. Pliocene: Basal Pliocene at San Diego (possibly should be assigned to the variety ruginodosa) ; loc. 201, upper horizon at Elsmere Canyon, one poor specimen, questionably identified (H. R. G.). The variety contignata is characterized at all stages of growth after it is above 10 mm. in altitude by strongly accentuated nodosity. The nodes on both the upper and lower angles are usually triple, becoming so on some specimens at a very early stage. They stand out like tridents, projecting more than 10 mm. on the body whorl of the type. In a few specimens only, and these specimens appear to be old but stunted forms showing the mature characteristics of strong angulations and recurved canal even on a small shell, the nodes have doubled but have gone no further. Even in these cases, however, the double nodes are much stronger than is normal on typical ocoyana. On casts the lower nodes are represented by connected vertical ridges, and on young speci- mens those ridges are almost knife edges. The type of contignata, which is of nearly the same size as the type of ruginodosa, is very strongly nodose, so that the whole surface of the body whorl above the upper angulation is thrown into radiating ridges, which bear such a strong resemblance to the radiating rafters on the unfinished roof of a circular pavihon (the projecting nodes playing the role of eave supports) that the variety is named contignata, "raftered." All of the specimens do not show the raftered effect on the upper part of the body whorl, and a few have single nodes on the upper angulation as on ruginodosa; but all have strongly projecting nodes, and the intergradations with the less strongly nodular ruginodosa do not appear to be common. The type of this variety is an extreme form, but it is of interest, for the excesses of its nodosity indicate the senile condition of the Trophosycon race in the lower Pliocene. The variety contignata can be distinguished by its strong nodosity from all other forms of Trophosycon; and its size when adult or its shape when young usually provide an additional means of distinguishing it from typical ocoyana. Sometimes, however, young specimens of contignata bear a closer resemblance to ocoyana than to nodibulb- osa, and it is barely possible that this variety has a different liistory from that of ruginodosa, in which case the latter should be referred to clallamensis or should be con- sidered a distinct species. The variety contignata is common in the lower Pico (lower PUocene) of Elsmere Canyon. The type is from the third fossiliferous stratum, about twenty feet above the contact with the metamorphic rocks on the north side of the main branch of Elsmere Canyon. This variety is also known from S. D. S. N. H. locality 227, south of Humph- reys Station, between Soledad and Placerita canyons, Los Angeles County, lower Pico; and from the JacaUtos (lower Etchegoin), lower PUocene of middle California. Probably also the San Diego PUocene specimen described by Arnold as Agasoma stanfordensis, and possibly the type of Ficus nodifera Gabb not Binkhorst, figured by Stewart as Ficus oregonensis, belong here. 750 San Diego Society of Natural History [Memoirs Ficus (Trophosycon) clallamensis Weaver Ficus clallamensis Weaver, Bull. No. 15, Washington State Geol. Survey, p. 74, pi. 9, fig. 73, 1912; Univ. Wash. Publ. Geol., Vol. 1, p. 30, 1916; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, p. 157, 1919. Trophosycon clallamense (Weaver), English, Univ. Calif. Publ. Geol., Vol. 8, p. 250, 1914. This species, originally described from the Clallam formation of Washington, the supposed equivalent of the Temblor formation of California, is more like a typical Ficus than is ocoyana. It has a low spire with a broad, slightly convex, gently sloping area above the upper angulation. The upper angle is smoothly curved, with small nodes which reflect through only as low, broader undulations and are not visible on the figure of the type specimen but are mentioned by Weaver in his description. They are present also on the California specimens and on specimens collected by Miss N. M. Tegland in Wash- ington. The lower angulation is indistinct and the nodes are very small, not showing at all on the cast. Weaver's specimen is large, comparable in size to Ficus ocoyana variety ruginodosa, but is different in shape and in the size of its nodes. A specimen from the Santa Margarita formation, upper Miocene of the northern portion of the Nipomo Quadrangle, San Luis Obispo County, California, is almost exactly like Weaver's type, as nearly as can be told from his figure and description. A specimen from the Temblor horizon in Orange County, California, here referred questionably to this species fits the description and the outline of the figure of Ficus clallamensis, except that it is not so large. The type of clallamensis is about 75 mm. in diameter, whereas the Orange County specimen measures only 50 mm., the altitudes not being comparable because the columellas are broken off in different places. On the Orange County specimen part of the shell and surface sculpture is preserved, the sculpture being not unlike that of Ficus ocoyana except that the minor spirals between the primaries are weaker, leaving the distant primaries to stand out more regularly and more prominently. Weaver mentions distant spirals as showing on the cast, (probably these markings are due to the impres- sions of the mould of the outer surface made after the shell had been dissolved out, for the inner surface of the shell of Trophosycon is usually not striated). There is in the Stanford collection from the type locality of Ficus clallamensis, or near it, a large complete cast 80 mm. in altitude and marked like that species but of the shape of Ficus ocoyana variety ruginodosa. It is possible that both of these large northern specimens (Weaver's type and the Stanford specimen) and also the large upper Miocene specimen from California are but variations in form of the same species, which is not yet clearly distinguishable from the various southern forms of other horizons only because no specimens upon which the shell is preserved have been available for comparison. In that case, the Orange County specimen may be but a variation of Ficus ocoyana analogous to the typical variation of clalla7nensis, and the large specimen from Washington with the ocoyana or ruginodosa shape may belong to one of those forms or may be the Clallam representative of their lineage intermediate between them. The material in hand, however, is not sufficient for an investigation of these possibilities. Another cast in the Stanford collection from the same locality (Clallam Light House, Straits of Fuca) has a low spire, a distorted shape with a broad canal, and irregular growth lines, with very inconspicuous nodes on the upper angulation and apparently no lower angulation. It has, however, the size and the faint spiral markings of the other specimen, of which it is probably but a variation. It is very similar to Ficus rodeoensis English, 1 which was described as a typical Ficus but which may be but the distorted variation of Ficus clallamensis or an earlier name for the variety nodibulbosa. > Univ. Calif. Publ. GooL, Vol. S, p. 246, pi. 24, 6g. 1, 1914. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CaLIFOKNIA 751 Ficus (Trophosycon) clallamensis Weaver variety nodibulbosa, new variety Plate 30, Figures 6a, 66 f Ficus sp. indet., Ficus cf. sianfordensis Arnold, etc., Clark, Univ. CaUf. Publ. Geol., Vol. 8, pp. 408, 422, 1915. ? Fiais cf. nodiferovs Gabb, Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 301, 1917. 9 "Ficus nodiferus Gabb," Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, p. 158 only, 1919. A Trophosycon of rather large size, shell of medium thickness, spire moderately low, apical angle about 105°, or if the body whorl is included m the measurement, 110°; whorls five, body whorl fairly large, its outhne marked by two rounded shoulders bearmg rows of rather inconspicuous nodes, the upper shoulder with an angle of about 125°, one-sixth of the distance from the suture to the anterior extremity as measured around the whorl, the lower shoulder with a very large and inconspicuous angle, about three-fifths of the way down, nodes about nine to a whorl on each shoulder, irregularly spaced, only about a quarter as wide as the interspaces, vertically elongate, with two cusps on those of the upper shoulder and two or three on those of the lower, the lower nodes apparently sometimes directly beneath the upper, inconspicuous and probably largely super- ficial, both rows showing but famtly on the cast and the lower not likely to show at all; spiral sculp- ture coarse and nearly all of the same strength, the primary and secondary series of ridges about equal m size, the tertiary scarcely ever visible, the total number of conspicuous spirals bemg about equal to the number of primary and secondary spirals on F. ocoyana; growth lines inconspicuous; anterior canal moderately long, broad, shallow, nearlj^ straight, columella smooth, hardly curving at all below the lower angle; outer lip tangential at the upper shoulder of the preceding whorl or abutting slightly below it. Dimensions of type: Altitude 85 mm. (canal defective, probably about 7 or 8 mm. broken off); diameter of body whorl 60 mm.; height of spire 13 mm. Type specimen: No. 2977-, at the California Academy of Sciences. Type locality: Santa Margarita formation, upper Miocene, of middle California. U. Miocene: At the type locality. This form is distinguishable from the adults of all other Trophosycons by its nearly straight columella; also from ocoyana and its varieties ruginodosa and contignata by its weak, thin nodes and rounded shoulders; from typical ocoyana by its size; from typical clalla7ne7isis and most of the others by the comparatively narrow slope on the body whorl above the upper shoulder and by its coarser, closer spirals; and from young specimens of ruginodosa by its coarser, scarcely differentiated spiral sculpture, by its weaker vertical cords, and by the fact that it retains its other peculiar characters when larger. The type was collected by F. M. Anderson from the Santa Margarita formation, upper Miocene, on the east side of section 25, T. 21 S., R. 14 E., Mt. Diablo B. & M., Fresno County, California. It is quite possible that Ficus rodeoensis English, referred to above, is an earlier name for this form, but the type specimen is such a poorly preserved, distorted indi- vidual and has such a different shape that the WTiters have hesitated to identify it until more material is found. Ficus rodeoensis has a very low spire with almost conical-sided whorls, entirely lacking a lower angulation, and showing no spiral sculpture. It is, however, of large size, probably a Trophosycon; and occurring in approximately the same horizon, it may be either this variety or typical clallamensis. 752 San Diego Society of Natural History [Memoirs Family CYPRAEIDAE Genus CYPRAEA Linnaeus, 1758 Cyprsea LinnaBus, Syst. Nat., Ed. 10, p. 718, 1758; Montfort, Syst., Vol. 2, p. 631, 1810. Type (by subsequent designation, Montfort, 1810), Cyprcea tigris Linnseus, figured by Tryon, Man. Conch., Ser. 1, Vol. 7, p. 180, pi. 11, figs. 49, 50, pi. 15, fig. 8, 1885, Indo-Pacific, Recent. Shell convolute, spire concealed by last whorl, which is very large, smooth or enameled, rarely postulose or nodulous; aperture long, narrow, lips thickened and both denticulate. Cypraea spadicea Swainson Plate 27, Figure 13 Cypnea spadicea Swainson, Tillock's Philos. Mag., Vol. 61, p. 376, 1823; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 182, pi. 13, fig. 78, 1885; Dall, U. S. Nat. Mus., Bull. 112, p. 140, 1921; Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 2, p. 237, 1927. Luponia spadicea Gray, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 657, 1864; Keep, West Coast Shells, p. 59, fig. 43, 1888, 1892. Luponia spadicea Swainson, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 78, 1868-9; Cooper, Seventh Ann. Rept. Calif. State Mineralogist, p. 247, 1888. Cyprsea spadicea Gray, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 288, 1903. Pliocene: S. D. S. N. H. locality 217a, middle Pliocene of Holser Canyon, Los Angeles County, one specimen (H. R. G.). Pleistocene: Santa Barbara Island (Cooper); upper San Pedro series of Deadman Island and of the lumber yard at San Pedro, Los Angeles County, one specimen at" each locality (Arnold). Recent: Santa Barbara, California, to Cedros Island, Lower California, Mexico (DaU). This species can be distinguished from C. annettoe Dall of southern waters by its narrower aperture, less curving inner lip, and more numerous teeth. C. annettoe has 19 teeth on the outer lip and 15 on the inner, while spadicea has 20 to 22 on the outer and 17 on the inner lip. Cypraea femandoensis Arnold Cypraia fernandoensis Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 538, pi. 50, figs. 8, 8a, 1907; U. S. Geol. Surv., BuU. 309, pi. 40, figs. 8, 8a, 1907; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914. Type specimen: In the U. S. National Museum, No. 164961. Type locality: In Elsmere Canyon, 2}^ miles southeast of Newhall, Los Angeles County, lower Pliocene. Pliocene: Lower Pliocene of Elsmere Canyon, Los Angeles County (Arnold; English). This form is probably an ancestral variety of spadicea. Cypraea annettae Dall Cyprsea sowerbyi ICiener, Spec. Gen. Icon. Coq. Viv., Vol. 1, Porcelaine, p. 38, pi. 7, fig. 5, 1845; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 185, pi. 15, fig. 9, 1885, not of Anton, 1839, nor Gray, 1832. Cyprsea ferruginosa Kiener, op. cit., p. 37, pi. 56, fig. 3, 1845, not of Gmelin, 1791. Cyprsea annellx Dall, Nautilus, Vol. 22, p. 125, April, 1909, new name for C. soioerbyi Kiener, not of Anton nor of Gray; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 227, 1909; Nautilus, Vol. 32, p. 24, 1918. Pleistocene: Upper conglomerate member of Santa Rosalia district, (coll. by M. E. Touwaide); Magdalena Bay Pleistocene (DaU, 1918); both in Lower California, Mexico. Recent: Gulf of California, Mexico, to Sechura Bay, Peru (DaU, 1909). This species is distinguished from C. spadicea Swainson by its wider aperture, greater curving of the inner lip, and fewer teeth. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 753 Cyprsea arabicula Lamarck Cyprxa arabicula Lamarck, Ann. Mus. Hist. Nat. Paris, Vol. 16, p. 100, 1810; EUst. Anim. s. Vert., Vol. 7, p. 399, 1822; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 175, pi. 9, figs. 35, 36, 1885; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 227, 1909. Pleistocene: Upper Pleistocene of coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Gulf of California, Mexico, to Paita, Peru (DaU). This is a rather small form with a strongly curved aperture and numerous teeth on the lips. Genus TRIVIA "Gray," Broderip, 1837 Trivia Broderip, Penny Cyclopedia, Vol. 8, p. 256, 1837, fide Iredale, Proc. Malac. Soc. London, Vol. 12, p. 35, 1916; Gray, Proc. Malac. Soc. London, Pt. 15, p. 142, 1847. Type (by subsequent designation, Gray, 1847), Cyprcea europoea Montagu ( = Valuta jonensis Pennant), figured by Tryon, Man. Conch., Ser. 1, Vol. 7, p. 205, pi. 23, figs. 48-51, 1885, coasts of Europe, Recent. Shell subglobular, cross-ribbed, front of columella internally concave, ribbed. (Tryon.) The species of this genus are like those of Cyproea in outward appearance, except that they are marked by strong circular ridges and are usually smaller. Trivia califomiana (Gray) Cyprxa califomiana Gray, Zool. Journ., Vol. 3, pt. 11, p. 365, December 31, 1827. Trivia californica Gray, Tryon, Man. Conch., Ser. 1, Vol. 7, p. 202, pi. 22, figs. 18, 19, 20, 1885; Keep, West Coast Shells, p. 60, figs. 44a, 445, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 288, 1903. Triiia califomiana Gray, Dall, U. S. Nat. Mus., Bull. 112, p. 140, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 238, 1927. Type specimen: In the British Museum. Type locality: California, Recent. Pleistocene: Upper San Pedro series of San Pedro (Arnold); upper Pleistocene of Santa Monica (in Oldroyd Collection at Stanford University); both Los Angeles County. Recent: Crescent City, California, to west Mexico (Dall). Trivia pustulata (Lamarck) Cyprxa pustulata Lamarck, Ann. Mus. Hist. Nat. Paris, Vol. 15, p. 101, 1810; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 197, pi. 20, figs. 45, 46, 52, 1885. Pleistocene: Coast of Oaxaca, Mexico (coll. by R. H. Palmer). Recent: Mazatlan, Mexico, to Panama (Tryon). This species is cross-ribbed on the apertural side of the shell but the reverse side has numerous pustules or rounded protuberances. Trivia radians (Lamarck) Cyprxa radians Lamarck, Ann. Mus. Hist. Nat. Paris, Vol. 16, p. 102, 1810; Hist. Anim. s. Vert., Vol. 7, p. 402, 1822. Triviaradians Lamarck, Tryon, Man. Conch., Ser. 1, Vol. 7, p. 202, pi. 22, figs. 13, 14, 1885; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 58, 1895; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 228, 1909; Nautilus, Vol. 32, p. 24, 1918; U. S. Nat. Mus., Bull. 112, p. 140, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 237, 1927. Pleistocene: Magdalena Bay, Lower California, Mexico (Dall, 1918); coast of Oaxaca, Mexico (coU. by R. H. Palmer). Recent: Santa Barbara and CataUna Island, California, to Ecuador (DaU, 1921). 754 San Diego Society of Natural History [Memoirs Trivia sanguinea (Gray in Sowerby) Cyprsea sanguinea Gray, in Sowerby's Conch. Illust., p. 13, fig. 32, 1832. Trivia sanguinea Gray, Tryon, Man. Conch., Ser. 1, Vol. 7, p. 203, pi. 22, figs. 21, 22, 1885; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 228, 1909; U. S. Nat. Mus., BuU. 112, p. 140, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 2, p. 237, 1927; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Catalina Island, California; Magdalena Bay, Lower California, to Salina Cruz, Mexico; Ecuador (DaU, 1921). Trivia solandri (Gray in Sowerby) Cyprsea solandri Gray, in Sowerby's Conch. Illust., p. 15, pi. 7, fig. 43, 1832. Trima solandri Gray, Tryon, Man. Conch., Ser. 1, Vol. 7, p. 202, pi. 22, figs. 15, 16, 1885; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 289, 1903; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 228, 1909; U. S. Nat. Mus., BuU. 112, p. 140, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 238, 1927. Pleistocene: Lower San Pedro series of Deadman Island, "one specimen" (Arnold), and upper Pleistocene of Santa Monica (Oldroyd Collection at Stanford University), Los Angeles County. Recent: Catalina Island, California, to Panama (DaU, 1921); ? Peru (DaU, 1909). Trivia ritteri Raymond "Trivia sanguinea Gray," in part of early California collectors, not of Gray in Sowerby, 1832. Triiia ritteri Raymond, NautUus, Vol. 17, p. 85, 1903; Lowe, Vol. 18, p. 20, 1904; DaU, U. S. Nat. Mus., BuU. 112, p. 140, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 238, 1927. Type specimeti: In the collection at the University of California. Type locality: Off Catalina Island, California, in 60 fathoms. Pliocene: Upper Phocene at Fifth and Hope streets, Los Angeles, California, three or four specimens (coU. by Charles M. Jay). Recent: Monterey and San Pedro, California, to Cortez Bank (DaU). This rare, white species is obtained in the living state only by dredging. The ribs are continuous across the back, the species differing in this respect from T. californiana (Gray). T. sanguinea (Gray in Sowerby), with which ritteri was formerly confused, is dark colored and the ribs are interrupted somewhat across the back. T. californiana has fewer and coarser ribs than either ritteri or sanguinea. Genus ERATO Risso, 1826 Erato Risso, Hist. Nat. Eur. Merid., Vol. 4, p. 240, 1826. Type (by monotypy), Erato cyprceola Risso, Italy, Miocene or Pliocene, figured by Risso, pi. 7, fig. 85. This genus differs from Cyprcea in that the spire is not entirely obscured by the extension of the aperture. Erato columbella Menke Erato colmnbella Menke, Zeitschr. f. Malakozool., Vol. 4, p. 183, Dec, 1847; Tryon, Man. Conch., Ser. 1, Vol. 5. p. 10, pi. 4, fig. 8, 1883; Keep, West Coast SheUs, p. 61, fig. 46, 1888, 1892; Cooper, Seventh Aim. Rept. Calif. State Mineralogist, p. 240, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 289, 1903; DaU, U. S. Nat. Mus., BuU. 112, p. 140, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 240, 1927. Type locality: Mazatlan, Mexico {fide Oldroyd). Pleistocene: Santa Barbara (Cooper); upper San Pedro series of San Pedro, "one specimen" (Arnold); Santa Monica (in Oldroyd CoUection at Stanford University); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Panama Bay (DaU, 1921). VoLrME I ] Pliocene and Pleistocene Mollusca of California 755 Family 8TR0MBIDAE Genus STROMBUS Linnaeus, 1758 Stromlms Linnaeus, Syst. Nat., Ed. 10, p. 742, 1758; Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 72, 1799, S. pugilis L. only example; Syst. Anim. s. Vert., p. 80, 1801; Montfort, Conch. Syst., Vol. 2, p. 515, 1801. Type (by subsequent designation, Montfort, 1810), Strombus pugilis Linnaeus; Caribbean, Recent; also fossil in Oaxaca, Mexico.' Strombus gracilior Sowerby Slrombus gracilior Sowerby, Cat. Shells Tankerville, Appen., p. xx, 1825; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 109, pi. 2, fig. 17, 1885; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 57, 1895; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 229, 1909; Nautilus, Vol. 32, p. 24, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 454, 1926. Pliocene: Coyote Mountain, Imperial County (Hanna). Pleistocene: Lower Pleistocene of Magdalena Bay (Dall; Jordan); upper Pleistocene of San Ignacio Lagoon (Jordan); both in Lower California, Mexico. Recent: La Paz, Lower California, and Gulf of California, Mexico, to Manta, Ecuador. This is a typical Strombus, it being the Pacific analogue of *S'. pugilis Linnaeus, the type of the genus. Strombus granulatus Mawe Strombus granulatus Mawe, Linnsean Syst. Conch., pp. 125, 127, pi. 25, fig. 3, 1823; Gray, in Wood's Index Test., Suppl., pi. 4, fig. 1, 1828; Sowerby, Thes. Conch., Vol. 1, p. 33, pi. 9, fig. 100, 1842. Slrombus granulatus Gray, Tryon, Man. Conch., Ser. 1, Vol. 7, p. 110, pi. 3, fig. 22, 1885; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 57, 1895; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 229, 1909; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. Type locality: California, Recent (Mawe). Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Gulf of California and Mazatlan, Mexico, to Manta, Ecuador, and Galapagos Islands. This species has frequently been attributed to Gray, 1828; but Mawe seems to have had the same shell, which he named S. granulatus in 1823. There is a Strombus granu- latus Swainson in the Appendix to the Bligh Catalogue, 1822, but this reference has not been available. Strombus obliteratus Hanna Strombus obliteratus Hanna, Proc. Cahf. Acad. Sci., Ser. 4, Vol. 14, p. 454, pi. 20, fig. 7, March 23, 1926. Type specimen: In the collection of the California Academy of Sciences, No. 1809. Type locality: Alverson Canyon, Coyote Mountain, Imperial County; Pliocene. Pliocene: Imperial formation. Coyote Mountain, California (Hanna). According to Hanna, this species is closely related to S. granulatus, but is shorter and stouter and has somewhat different and more prominent spinose sculpture. Thirty- three specimens of obliteratus were examined by Hanna, who observed no intergi'adation with granulatus in the differential characters mentioned. ' Bose, Inst. Geol. Mexico. Bull. No. 22. p. 35, pi. 4, figs. 1-6, 1906. Pliocene at Tuxtcpec, Oaxaca. 756 San Diego Society of Natural History [Memoirs Strombus galeatus Swainson Strombtts galeatus W. Swainson, Philos. Mag., Vol. 62, p. 401, December, 1823; Reeve, Conch. Icon., Vol. 6, Strombus, pi. 3, fig. 3, 1850; Tryon, Man. Conch., Vol. 7, p. 108, pi. 1, fig. 6, 1885; Stearns, Proc. U. S. Nat. Mus., Vol. 17, p. 190, 1894; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 57, 1895; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 454, 1926; Hanna and Hertlein, Vol. 16, p. 143, 1927. Pliocene: Imperial formation of Coyote Mountain, Imperial County (Hanna) ; Santa Antonita Point, Coro- nados Island, Carmen Island, and Ceralbo Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Gulf of California, Mexico (Stearns); Panama to Mazatlan, Acapulco (Tryon). This is a large species with the aperture elongated so that the spire appears relatively low. Family CLAVIDAE Genus CERITHIUM Bruguiere, 1789 Cerithnim BruguiJre, Ency. Meth. Hist. Nat. Vers, Vol. 1, p. xv, 1789, p. 467, 1792; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 355, 1927. Stewart has shown that Cerithium Bruguiere must be considered a synonym of Clava Martyn unless Cerithium adansonii Bruguiere is adopted as type on the basis of indirect virtual tautonymy. As this method of type designation is ineffective when opposed to a valid subsequent designation, Cerithium must be dropped in favor of Clava unless a suspension of the rules is obtained. In anticipation of such a protective action on the part of the International Commission on Zoological Nomenclature, the generic name Cerithium is here used with C. adansonii Bruguiere as type. Vignal/ Cossmann,^ and others have used C. adansonii as the type of Cerithium.^ "Cerithium" adustum Kiener Cerithium adustum Kiener, Sp^c. G6n. Icon. Coq. Viv., Vol. 5, Cerite, p. 37, pi. 13, fig. 2, 1841 (or 1842?); Tryon, Man. Conch., Ser. 1, Vol. 9, p. 126, pi. 21, fig. 52, not fig. 51, 1887; Mabille, Bull. Soc. PhHomathique de Paris, Ser. 8, Vol. 7, p. 57, 1895; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Magdalena Bay, Lower California, Me.xico, to Panama and the Galapagos Islands. Kiener's figure of this species is of a dark shell with a few small nodosities, a rather deep, straight posterior canal, and a short, straight anterior canal. It does not have the strong nodosities of "C" maculosum Kiener. Kiener gave the habitat as the Indian Ocean and Red Sea, which appears to be an error. Tryon gives the range as Mazatlan to Panama and the Galapagos Islands. Jordan reported the species as Recent at Magdalena Bay. "Cerithium" stercus-muscarum Valenciennes Cerithium stercus-muscarum Valenciennes, in Rec. Observ. Zool., Humboldt et Bonpland, Vol. 2, p. 278, 1833; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 229, 1909; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 142, 1927. Type locality: Acapulco, Mexico, Recent. Pliocene: Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Cedros Island, Lower California, Mexico, to Tumbes, Peru, and the Galapagos Islands (DaU). ■ Journ. de Conchyl., Vol. 58. pp. 138-140, 1910. ' Ann. Soc. Roy. Malac. Belg., Vol. 24, p. 10, 1889. ' In addition to Stewart's discussion referred to above the reader should consult Dall, "On the Synonymic History of the Genera Clava Martyn and Cerithium Bruguiere," Proc. Acad. Nat. Sci. Phila.. 1907, pp. 363-369. 1907. E. Wood has published some interesting informa- tion on "The Phylogeny of Certain Cerithiidx" in Vol. 20 of the New York Academy of Sciences, 1910. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 757 "Cerithium" ocellatum Bruguiere Cerithium ocellatum Bruguiere, Ency. Meth. Hist. Nat. Vers, Vol. 1, p. 499, 1792; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 132, pi. 24, fig. 19, 1887; Mabille, Bull. Soc. PhUom. Paris, Ser. 8, Vol. 7, p. 57, 1895; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 229, 1909; E. K. Jordan, Bull. So. CaUf. Acad. Sci., Vol. 23, pp. 149, 151, 1924. Pleistocene: Lower Quaternary at Magdalena Bay and upper Quaternary at San Ignacio Lagoon, Lower California, Mexico (Jordan). Recent: Lower California, Mexico, to Panama and the Galapagos Islands. "Cerithium" simplicius, new species Plate 24, Figure 11 Shell of medium size, high spired; whorls moderately ventricose, particularly on the upper haK of each whorl, the lower haK being nearly straight m profile; sculptured with numerous, fijie, equally spaced spiral striations, about 16 to 18 per whorl, and very low broad axial undulations which probably represent the parietal callus pile deposited during restmg stages, their being three or four per whorl, all somewhat concentrated axially at about a quarter of the distance from the upper to the lower suture; aperture imperfect, but clearly showing a small anterior canal, which is slightly twisted to the left, and a callus deposit on the parietal wall at the position of the posterior canal, which, during growth, produces the low bulges mentioned above. Dimensions of tyi^e specimen: Altitude (mcomplete), 32 mm.; maximum diameter, 13 mm. Type specimen: No. 207, in the collection of the San Diego Society of Natural History. Type locality: S. D. S. N. H. locality 2176, Holser Canyon, north side of Santa Clara Valley, Los Angeles County, middle Pliocene. Pliocene: Middle Pliocene at the type locality, the type and several paratypes (H. R. G.). The most characteristic feature of this interesting species is its lack of axial ribs. It is entirely unlike the strongly nodulose species from the Mexican coast. It does not have the flange-like anterior canal nor the axial ribs of Cerithidea calif ornica (Haldeman), and indeed it is much larger and entirely unlike that species. The writers know of no species that is at all similar to simplicius. It is far from being a typical "Cerithium," but until better specimens are available it is placed here tentatively. Genus THERICIUM Rochebrune in Monterosato, 1890 Tliericivm Rochebrune, Monterosato, Naturalista Siciliano, Year 9, no. 7, p. 163, 1890; Woodring, Carnegie Inst., Publ. No. 385, p. 332, 1928. Vulgocerithium Cossmann, Ess. Paleo. Comp., Vol. 7, p. 77, 1906. Type (by original designation), Cerithium. vulgatum Bruguiere, Mediterranean, Recent {fide Woodring); figured by Reeve, Conch. Icon., Vol. 15, Cerithium,, pi. 2, fig. 9, 1865. If Cerithium is retained by a suspension of the International Rules of Nomen- clature, Thericium should probably be considered at most a subgenus. In examining a representative collection of Cerithioids, it will be noticed that the apertural and sculp- tural characters occur in somewhat confusing combinations, and it is likely that a separation of Thericium is more artificial than natural. The family is in need of a critical review, which would far exceed the time and space limitations of this paper. Thericium incisum (Sowerby) Cerithium incisum Sowerby, Thes. Conch., Vol. 2, p. 868, pi. 182, fig. 152, 1855; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 142, pi. 27, fig. 22, 1887; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 445, 1926. Pliocene: Coyote Mountain, Imperial County (Hanna). Recent: Lower California and Guaymas, Mexico (Tryon). "Cerithium" sculptum and curium Sowerby are both much shorter shells than incisum, according to Sowerby's figures, though curtum may be a variety or variant of incisum. 758 San Diego Society of Natural History [Memoirs Genus CLAVA Martyn, 1784 Clava Martyn, Univ. Conch., Vol. 1, Nos. 12, 13, 1784; Pilsbry, Proc. Aead. Nat. Sci. PhUa. for 1901, p. 392. Type (by subsequent designation, Pilsbry, 1901), Clava rugata Martyn. Clava gemmata (Hinds) Cerithium gemtnatum Hinds, Zool. Voy. Sulphur, Moll., p. 27, 1844; Dall, Nautilus, Vol. 32, p. 24, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. Cerithium (Vertagus) gemmatum Hinds, Tryon, Man. Conch., Ser. 1, Vol. 9, p. 146, pi. 28, fig. 44, 1887. Pleistocene: Magdalena Bay, Lower California, Me.vico (Dall; Jordan, as lower Pleistocene). Recent: Gulf of California, Mexico, to Panama (Jordan). The well-developed spiral lamina on the columella and the reflexed anterior canal place this species in Clava Martyn. It is the type of the subgenus Ochetoclava Woodring,' characterized by the shorter and less horizontal canal and strongly ascending outer lip, which produces a long posterior channel. Clava? lordii (Yates),- a form described from a single beach- worn specimen retaining only the body whorl and part of the penultimate whorl, appears as figured to be some- what like C. gemmata; but it has more numerous rows of nodules. It came from the Santa Barbara Channel near EUwood, Santa Barbara County. It may have been a ballast shell or a fossil washed out on the beach. Potamides cyclus Dall may be a synonym of lordii.^ Genus DIASTOMA Deshayes, 1861 Diastema fastigiatum (Carpenter) Bittium fastigiatiun Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 65.5, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 5, p. 181, 1865. Diastoma fasligiata Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 39, p. 581, text fig. 1, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 144, 1921. Pleistocene: Santa Barbara (Carpenter; Bartsch, as "lower Pleistocene," ? probably upper Pliocene). ? Recent: Santa Barbara, California. Genus ALABINA DaU, 1902 Elachista Dall and Bartsch, Nautilus, Vol. 15, p. 58, September, 1901, not Elachisia Treitschke, 1833. AlaUna DaU, NautOus, Vol. 15, p. 127, 1902. Type (by original designation), Bittiuvi cerithidioide Dall, Florida, Pliocene and Recent. Alabina barbarensis Bartsch AlaUna barbarensis Bartsch, Proc. U. S. Nat. Mus., Vol. 39, p. 411, pi. 61, fig. 3, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 145, 1921. Pleistocene: Santa Barbara (Bartsch), probably upper Pliocene. ? Recent: Santa Barbara, California. Alabina califomica (Dall and Bartsch) Bittium (Elachista) californicum Dall and Bartsch, Nautilus, Vol. 15, p. 58, 1901. Bittium californicum Dall and Bartsch, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 291, pi. 4, fig. 4, 1903. AlaUna califomica DaU and Bartsch, Bartsch, Proc. U. S. Nat. Mus., Vol. 39, p. 414, pi. 62, fig. 7, 1911; DaU, U. S. Nat. Mus., Bull. 112, p. 145, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925. Pleistocene: Lower San Pedro series at San Pedro (Arnold), at Nob HiU cut (Oldroyd), and Deadman Island (Bartsch, 1911). Recent: San Diego (Gripp ?). 1 Carnegie Inst. Wash., Publ. No. 385, p. 334, 1928; type (by original designation) Cerithium gemmatum Hinds. « Vertagus lordii Yates, Santa Barbara Soc. Nat. Hist., Bull. No. 2, p. 47, pi. 2, figs. 6, 7, August, 1S90. > Proc. U. S. Nat. Mus., Vol. 56, p. 346, 1919; Long Beach, California, to Gulf of California. VoLtjME I ] Pliocene and Pleistocene Mollusca of California 759 Alabina hamlini Bartsch Alabina hamlini Bartsch, Proc. U. S. Nat. Mus., Vol. 39, p. 411, pi. 61, fig. 2, 1911; Dall, Bull. 112, U. S. Nat. Mus., p. 145, 1921. Pleistocene: "The type and 19 specmiens .... were collected in the Post-Pliocene deposits at HaUenbeck's well, Los Angeles, California" (Bartsch). Alabina io Bartsch AlaUna io Bartsch, Proc. U. S. Nat. Mus., Vol. 39, p. 415, pi. 61, fig. 1, 1911; Dall, U. S. Nat. Mus., BuU. 112, p. 145, 1921. Pleistocene: "Post-Pliocene beds of San Diego, California" (Bartsch); "Signal Hill, Long Beach, California, Pleistocene" (Dall). Alabina monicensis Bartsch Alabina monicensis Bartsch, Proc. TJ. S. Nat. Mus., Vol. 39, p. 415, pi. 62, fig. 5, 1911. Pleistocene: Upper San Pedro series at Santa Monica, Los Angeles County (Bartsch). Genus BITTIUM Leach, in Gray, 1847 Bittium Leach, Gray, Ann. Mag. Nat. Hist., Vol. 20, p. 270, October, 1847; Proc. Zool. Soc. London for 1847, p. 154, November, 1847. Type (by subsequent designation, Gray, Nov., 1847), Murex reticulatus Montagu {= Stromhiformis reticulatus Da Costa), European seas, Recent. Bartsch' has given the following key to the subgenera of BiUiurn occurring on the Pacific coast of North America: Nuclear whorls with two spiral lirations: Postnuclear whorls having varices Bittium, s. s. Postnuclear whorls without varices Lirobittium Bartsch Nuclear whorls smooth : Spiral sculpture predominating over axial Stylidium Dall Spiral sculpture not predominating over axial Semibittium Cossmann These subdivisions are probably entirely artificial and should be discarded as soon as a natural classification can be worked out, if not before. B. asperum, for instance, has its specific relatives in Semibittium, but is classed in Lirobittium. Subgenus LIROBITTIUM Bartsch, 1911 hirohitliuni Bartsch, Proc. U. S. Nat. Mus., Vol. 40, j). 384, 1911. Type (by original designation), B. catalinense Bartsch, 1907. Bittium (Lirobittium) catalinense Bartsch Bittium catalinensis Bartsch, Smithsonian Misc. Coll., Quarterly Issue, Vol. 50, Pt. 4, p. 28, pi. 57, fig. 13, 1907. Bittium (lAroUttium) catalinense Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 402, pi. 51, fig. 1, 1911; Dall, Bidl. 112, U. S. Nat. Mus., p. 147, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925. Bittium [hirobiltium) catalinense inornatxim. Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 403, pi. 51, fig. 3, 1911; DaU, U. S. Nat. Mus. Bull. 112, p. 147, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 32, pi. 75, fig. 3, 1927. ' "The Recent and Fossil Mollusks of the Genus Bittium from the West Coast of .\merica." Proc. U. S. Nat. .Mus., Vol. 40. pp. 383-414. pis. 51-58, May 12, 1911. 760 San Diego Society of Natural History [Memoirs Pleistocene: Lower San Pedro series of Deadman Island (Bartsch), and of Nob Hill cut (Oldroyd); Santa Barbara and San Diego (Bartsch). Recent: Catalina Island to San Diego, California (Dall). Bittium (Semibittium) subplanatum Bartsch is probably closely related to this species. The variety inornatum Bartsch is of little significance. Bittium (Lirobittium) omatissimum Bartsch Bittium (Lirobittium) ornatissimum Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 403, pi. 52, figs. 4, 5, 1911; Dall, BuU. 112, U. S. Nat. Mus., p. 147, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925. Pleistocene: Lower San Pedro series of Deadman Island (Bartsch) and of Nob Hill cut (Oldroyd), San Pedro, Los Angeles County; Santa Barbara (Bartsch). Recent: San Pedro (Dall). Bittium (Lirobittium) interfossum (Carpenter) Rissoa interfossa Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 656, 1864. Cerithiopsis fortior Carpenter, op. cit., p. 660, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 337, 1865. Rissoina interfossa Carpenter, Proc. Calif. Acad. Sci., Vol. 3, p. 217, 1866. Bittium (Lirobittium) interfossa Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 401, pi. 51, figs. 2, 6, 1911; Dall, U. S. Nat. Mus,, Bull. 112, p. 147, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey to San Diego, California (Dall); San Martin Island, Lower California, Mexico (F. C. Baker). Bittitun (Lirobittium) asperum (Gabb) Turbonilla aspera Gabb, Proc. Acad. Nat. Sci. Phila. for 1861, p. 368. Bittium asperum Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 12, pi. 2, fig. 20, 1866; Tryon, Man. Conch., Vol. 9, p. 153, pi. 30, fig. 7, 1887; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 230, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 291, 1903; Berry, Nautilus, Vol. 22, p. .38, 1908; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914, not positively identified; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 357, pi. 32, fig. 7, text fig. 4, 1927. Bittium barbarense Bartsch, Smithsonian Misc. Coll., Quarterly Issue, Vol. 50, Pt. 4, p. 28, pi. 57, fig. 15, 1907. Bittium (Lirohittium) asperum Gabb, Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 405, pi. 56, fig. 3, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 147, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, pp. 78, 79, 1929. Pliocene: "Pico" formation near Ventura (Waterfall); questionably at Holser and Elsmere canyons, Los Angeles County (English); San Diego well, San Diego (Dall); Santa Barbara, probably in upper- most Pliocene (Arnold; Berry; Bartsch); etc. Pleistocene: Santa Barbara to San Diego (Cooper); "Pliocene" of Deadman Island and Timm's Point; lower San Pedro series at Deadman Island, "rare"; Barlow's Ranch, near Ventura; upper San Pedro series at Crawfish George's and San Pedro; Pacific Beach, San Diego (Arnold). Recent: As variety loma'ense Bartsch, 1911, and probably also the typical variety; Catalina Island to San Diego, California. Bittium (Lirobittium) asperum (Gabb) variety dilatatum, new variety Plate 24, Figure 14 Shell like that of the tj^jical variety but relatively much shorter and broader, with coarser sculpture, fewer spirals, and fewer axials. Length, about 6 mm. (specimen incomplete) ; width of last whorl, about 3 mm. Type specimen: In the collection of the San Diego Society of Natural History, No. 210. Type locality: S. D. S. N. H. locality 2176, at the head of Holser Canyon, Los Angeles County; middle Pliocene. Volume 1] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 761 Pliocene: Middle Pliocene at the type locality (H. R. G.). Notwithstanding tlie considerable number of named species, or supposed species, of Bittium from California, the specimen described above appears distinct enough to be of significance. It is probably not merely the young of some other form, for the early whorls of larger shells do not have such strong sculpture nor such a dilated angle. Subgenus STYLIDIUM Ball, 1907 Stylidium Dall, in Bartsch, Proc. U. S. Nat. Mus., Vol. 3.3, p. 178, October 23, 1907; Ball, U. S. Geol. Surv., Prof. Paper 59, p. 76, April 2, 1909. Type (by original designation), Bittium eschrichtii (Middendorff). Of the subgenera of Bittium now in use, this one alone seems to be recognizable, and yet it is probably of little more than specific value. Bittium (Stylidium) eschrichtii (Middendorff) Plate 24, Figure 9 Cerithium filosum Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 120, 1S49, not CerUkium fdosum Philippi, Zeitschr. f. Malakozool. for 1848, p. 143, March, 1849. Twrildla eschrichtii Middendorff, Mem. Acad. Imp. Sci., St. Petersb., Vol. 8, p. 396, pi. 11, fig. 1, August, 1849. Bittium filosum Gould, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 65.5, 1864; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 152, pi. 29, fig. 90, 1887; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 230, 1888; Keep, West Coast Shells, p. 72, fig. 57, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 292, 1903; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 239, 1916. Bittium {Stylidium) eschrichtii Middendorff, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 76, pi. 14, fig. 2, 1909; Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 387, pi. 58, fig. 4, 1911; DaU, U. S. Nat. Mus., Bull. 112, p. 145, 1921. Stylidium eschrichti Middendorff, Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 593, 1913. Pliocene: Merced-Purisima south of San Francisco (Arnold and Hannibal); Coos conglomerate at Fossil Rock, Coos Bay, Oregon, possibly Pleistocene (Dall); upper Wildcat formation, Humboldt County (Martin). Pleistocene: Rare in lower and upper San Pedro series at Deadman Island and San Pedro; "a few found at Crawfish George's," Los Angeles County (Arnold); Santa Barbara (Cooper). Recent: Sitka, Alaska, to Puget Sound (Dall, 1921). Berry's report of this species at Monterey may refer to the variety montereyense Bartsch. Bittium (Stylidium) eschrichtii (Middendorff) variety montereyense Bartsch Bittium {Stylidium) eschrichti monlereyensis Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 178, 1907. Bittium {Stylidium) eschrichtii nwntereyense Bartsch, Proc. U. 8. Nat. Mus., Vol. 40, p. 389, pi. 58, fig. 5, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 146, 1921. f Pliocene: Ubi ? (DaU, 1921). Pleistocene: Deadman Island, Los Angeles County (Bartsch, 1911). Recent: Crescent City, California, to Cape San Lucas, Lower California, Mexico (Dall, 1921). Dall reported this species as Phocene but gave no locality. Probably his record referred to the Deadman Island Pleistocene occurrence. Subgenus SEMIBITTIUM Cossmann, 1896 lust. Coq. Foss. Env. Paris, App, 2, p. 29, 1896; Type, Cerithium cancellatum Lamarck, Eocene of France. SemiUttium Cossmann, Cat. Illust. Coq. Foss. Env. Paris, App. 2, p. 29, 1896; Ess. Paleo. Comp., Vol. 7, p. 138, 1906. 762 San Diego Society of Natural History [Memoirs Bittium (Semibittium) annillatuin Carpenter Billium armillatum Carpenter, Brit. Assn. Adv. Sci., Rcpt. for 1863, p. 655, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 18, p. 276, 1866; Baker, NautUus, Vol. 16, p. 41, 1902. Billium (Semibillium) armillalum Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 391, pi. 52, fig. 6, 1911. ? Semibittium armillatum Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 146, 1921. ? Upper Pliocene: Santa Barbara (type locality). Pleistocene: ? Santa Barbara (Carpenter, type locality; Bartsch); San Pedro (Bartsch). Recent: ? "Santa Barbara and San Pedro, California. Pleistocene" (Dall); San Martin Island, Lower California, Mexico (Baker). Bittium (Semibittium) attenuatum Carpenter Bittium attenuatum Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 655, 1864; Journ. de Conchyl., Vol. 12, p. 242, 1865; Baker, Nautilus, Vol. 16, p. 41, 1902; Lowe, Vol. 27, p. 27, 1913; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925. Bittium (? var.) esuriens Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 655, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 181, 1865; Journ. de Conchyl., Vol. 12, p. 242, 1865. Bittium (Semibittium) attenuatum Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 393, pi. 54, figs. 1, 2, 5, 1911; DaU, U. S. Nat. Mus., Bull. 112, p. 146, 1921. Pleistocene: Lower San Pedro series of Deadman Island (Bartsch) and of Nob Hill cut, San Pedro (T. S. Oldroyd), Los Angeles County. Recent: Forrester Island, Alaska, to San Diego, California (Dall); San Martin Island (Baker) and San Geronimo Island (Lowe), Lower California, Mexico. Bittium (Semibittium) rugatum Carpenter Plate 24, Figure 8 Bittium rugatum Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 539, 1864, list name; Ann. Mag. Nat. Hist., Ser. 3, Vol. 17, p. 276, 1866; Arnold, Mem. Calif. Acad. Soi., Vol. 3, p. 295, pi. 4, fig. 11, 1903; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Bittium (Semibittium) rugatum Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 397, pi. 56, figs. 4, 5, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 146, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925. f Pliocene: Santa Barbara (Carpenter — It is not known exactly where Carpenter's material came from, and it may have been Pleistocene). Pleistocene: Lower San Pedro series at Deadman Island and San Pedro, "common" (Arnold); Nob Hill cut, San Pedro (T. S. Oldroyd); Santa Barbara (Bartsch); upper San Pedro series of San Pedro region (Arnold); San Diego (Bartsch); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan); upper Pleistocene southwest of Goleta, Santa Barbara Co. Recent: San Pedro and Catalina Island (Dall). Bittium ( Semibittium) quadrifilatum Carpenter Bittium quadrifilatum Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 655, 1864; Journ. de Conchyl., Ser. 3, Vol. 5, p. 143, 1865; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 153, pi. 29, fig. 91, 1887; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 230, 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 205, pi. 21, fig. 4, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 292, pi. 9, fig. 2, 1903. Bittium (quadrifilatum Cpr. ?) Berry, Nautilus, Vol. 22, p. 38, 1908. Bittium (Semibittium) quadrifilatum Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 398, pi. 68, figs. 2, 3, 1911; Dall, U. S. Nat. Mus., BuU. 112, p. 146, 1921. Pliocene: Bath-house Beach, Santa Barbara (Arnold). Pleistocene: Lower and upper San Pedro series of San Pedro region, Los Angeles County (Arnold). Recent: Monterey, California, to San Ignacio Lagoon, Lower California, Mexico (Dall). Bittium (Semibittium) larum Bartsch Bittium (Semibittium) larum Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 407, pi. 57, fig. 4, 1911. Bittium larum (?) Bartsch, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924. f Pleistocene: Lower Quaternary at Magdalena Bay, Lower California (Jordan, doubtfully identified by Bartsch). Recent: San Pedro, California, to San Bartolome Bay, Lower California, Mexico (Jordan). Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 763 This species is closely related to Bittium (Lirobittium) catalinense Bartsch which in turn is closely related to Bittium {Semibittium) subplanatum Bartsch. These specific relationships, which become apparent when a large number of specimens are examined, illustrate the artificial and misleading character of the supposed subgeneric divisions now in use. Incertae Sedis Bittium giganteum Bartsch Bittium giganteum Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 410, pi. 55, fig. 2, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 148, 1921. Pleistocene: San Diego, the type locality; San Pedro (Bartsch). Bittium casmaliense Bartsch Bittium casmaliense Bartsch, op. dt., p. 411, pi. 55, fig. 3, 1911. Pliocene: Railroad cut one mile north of Schumann, Santa Barbara County (Bartsch). Bittium amoldi Bartsch Bittium amoldi Bartsch, op. cit., p. 411, pi. 56, fig. 1, 1911. Pliocene: Waldorf asphalt mine, three miles southeast of Guadalupe, Santa Barbara County (Bartsch). Some of the species of Bittium, such as B. sanjuanense Bartsch, are difficult to separate from Tachyrhynchus Morch, the differences being in the operculum. Bittium has a paucispiral operculum with the nucleus not central, while Tachyrhynchus has a multispiral operculum with a central nucleus. Genus CERITHmEA Swainson, 1840 Shell high spired, Turritelloid, of many regularly enlarging whorls; columella smooth, not plicated; outer lip sometimes thickened; anterior canal a narrow groove or reduced to a small flange. Cerithidea califomica (Haldeman) Plate 24, Figures 6, 7 Cerithium califomictim Haldeman, Monog. Freshwater Shells N. Amer,, cover of No. 1, 1840. Cerithium {Potamis) sacratum Gould, Proc. Boston See. Nat. Hist., Vol. 3, p. 118, 1849; IT. S. Expl. Exped., Vol. 12, p. 114, 1852, Atlas, pi. 10, fig. 116, 1856. Potamis pullatus Gould, U. S. Pacific R. R. Repts., Vol. 5, p. 333, pi. 11, figs. 23, 24, 1856. Cerithidea californica Haldeman, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 79, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 233, 1888; DaU, Trans. Wagner Inst. Sci., Vol. 3, p. 277, 1892; ,\rnoId, Mem. Calif. Acad. Sci., Vol. 3, p. 296, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 148, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 253, 1929. Cerithidea sacrata Gould, variety hyporhyssa Berry, NautUus, Vol. 19, p. 132, te.xt figure, 1906. Pliocene: San Fernando, Los Angeles County (Cooper). Pleistocene: San Pedro to San Diego (Cooper); "Pliocene," lower and upper San Pedro series of San Pedro region, very common in the upper San Pedro (.\rnold); Newport Pleistocene (Strong and Grant); "Saugus" formation near Ventura (Waterfall); Twenty-sixth Street, Pacific Beach (Arnold), and east side of Mission Bay (Stephens), San Diego; lower Quaternary at Magdalena Bay and upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1924, 1926); etc. Recent: Baulinas Bay to San Diego, California (Dall, 1921); San Martin Island, Lower California, Mexico (F. Baker). 764 San Diego Society of Natural History i Memoirs This species is often excessively abundant on mud flats in the bays of California. The variety hyporhyssa is an individual variant or a pathologic form with very subdued sculpture and a higher spire. It is not a valid variety. Genus SEILA A. Adams, 1861 Sella montereyensls Bartsch "Cerilhiopsis assimilata C. B. Adams," Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 233, 1888, not C. assimilata C. B. Adams, 1852. "Seila assimilata C. B. Adams," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 290, pi. 4, fig. 8, 1903; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929; not of C. B. Adams, 1852. Seila nwntereyensis Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 176, October 23, 1907; Dall, IT. S. Nat. Mus., Bull. 112, p. 144, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 15, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pliocene: Fifth and Hope streets, Los Angeles, lower part of upper Pliocene (U. S. G.). Pleistocene: Lower San Pedro series at Nob HID cut (Oldroyd) and San Pedro (Arnold) ; San Diego (Cooper) ; Santa Monica (coU. of F. C. Clark); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Todos Santos Bay, Lower California, Mexico (Dall). This species is much larger than the true S. assimilata C. B. Adams, of the Panama region. Family CERITHIOPSIDAE Genus CERITHIOPSIS Forbes and Hanley, 1853 Cerithiopsis Forbes and Hanley, Hist. Brit. Moll., Vol. 3, p. 364, 1853. Type (by monotypy), Murex tubercularis Montagu, European Seas, Recent. Section Cerithiopsis, s. s. Cerithiopsis fatua Bartsch Cerithiopsis (Cerithiopsis) fatva Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 331, pi. 36, fig. 5, May 8, 1911. Cerithiopsis fatua Bartsch, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 15, 1925. Pleistocene: Lower San Pedro series of Deadman Island (Bartsch) and Nob Hill cut, San Pedro (Oldroyd). Cerithiopsis halia Bartsch Cerithiopsis (Cerithiopsis) halia Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 344, pi. 40, fig. 8, 1911. Cerithiopsis halia Bartsch, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Me.xico (Jordan). Recent: Todos Santos Bay to Cape San Lucas, Lower California, Mexico (Bartsch). Cerithiopsis grippi Bartsch Cerithiopsis (Cerithiopsis) grippi Bartsch, Proc. U. S. Nat. Mus., Vol. 52, p. 669, pi. 46, fig. 12, 1917. Cerithiopsis grippi Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 143, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Diego, California (Bartsch). Cerithiopsis montereyensis Bartsch Cerithiopsis montereyensis Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 363, pi. 41, fig. 5, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 143, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Little River, Mendocino County, to Monterey, California (Dall). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 765 Section Cerithiopsida Bartsch, 1911 Cerithiopsida Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 329, 1911. Type (by original designation), Cerithiopsis {Cerithiopsida) diegensis Bartsch. Cerithiopsis diegensis Bartsch Cerithiopsis (Cerithiopsida) diegensis Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 347, pi. 40, fig. 4, 1911. Cerithiopsis diegensis Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 143, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro to San Clemente Island, California, south to South Coronado Island, Lower California, Mexico (DaU). Section Cerxthiopsina Bartsch, 1911 Cerithiopsina Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 328, 1911. Type, Cerithiopsis necropolitana Bartsch. Cerithiopsis necropolitana Bartsch Cerithiopsis (Cerithiopsina) necropolitana Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 345, pi. 39, fig. 1, 1911. Cerithiopsis necropolitana Bartsch, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 15, 1925. Pleistocene: Lower San Pedro series of Deadman Island (Bartsch) and of Nob Hill cut (Oldroyd), San Pedro. Section Cerithiopsidella Bartsch, 1911 Cerithiopsidella Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 329, 1911. Type (by original designation), Cerithiopsis cosmia Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 180, 1907; Vol. 40, p. 348, pi. 38, fig. 7, 1911, Monterey, California, to Lower CaMfornia, Mexico, Recent. Cerithiopsis antefilosa Bartsch Cerithiopsis (Cerithiopsidella) antefilosa Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 349, pi. 40, fig. 9, 1911. Cerithiopsis antefilosa Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 143, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro to San Diego, California (Dall). Cerithiopsis alcima Bartsch Cerithiopsis (Cerithiopsidella) alcima Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 350, pi. 39, fig. 2, 1911. Cerithiopsis alcima Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 144, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to San Geronimo Island, Lower California, Mexico. Section ? Cerithiopsis fossiUs Bartsch Cerithiopsis fossilis Bartsch, Proc. U. S. Nat. Mus., Vol. 40, p. 353, pi. 38, fig. 3, 1911; T. S. Oldroyd, Vol. 65, Art. 22, p. 15, 1925. Pleistocene: Lower San Pedro series of Deadman Island (Bartsch) and of Nob Hill cut near San Pedro (Oldroyd), Los Angeles County. 766 San Diego Society of Natural History [Memoirs Cerithiopsis williamsoni (Arnold) Billium williamsoni Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 295, pi. 6, fig. 11, 1903. Cerithiopsis williamsoni Arnold, Bartsch, Proc. U. S. Nat. Mus., Vol. 40, pi. 39, fig. 6, 1911. Pleistocene: Upper San Pedro series of San Pedro; Spanish Bight, San Diego (Arnold). Genus METAXIA Monterosato, 1884 Metaxia Monterosato, Nomen. Gen. Spec. Conch. Medit., p. 125, 1884; Cossmann, Ess. Paleo. Comp., Vol. 7, p. 148, 1906. Type (by subsequent designation, Cossmann, 1906), Cerithium rugulosum Sowerby (+ "Cerithiopsis metaxoe Delle Chiaje" Monterosato, ante 1884, possibly not Murex metaxa S. Delle Chiaje, Mem. An. s. Vert. Napoli, Vol. 3, p. 222, 1828). Metaxia diadema Bartsch Metaxia diadema Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 182, 1907; Dall, U. S. Nat. Mus., Bull. 112, p. 144, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 15, 1925. Pleistocene: Lower San Pedro series at Nob Hill cut, San Pedro (T. S. Oldroyd) ; palisades of Santa Monica (collection of F. C. Clark), both in Los Angeles County. Recent: Monterey to San Diego, California (Bartsch). Family TRIPHORIDAE Genus TRIPHORA Blainville, 1828 Triphora BlainvUle, Diet. Sci. Nat., Vol. 55, p. 344, 1828. Type (by monotypy) , Triphora gemmatum Blainville ( = Cerithium tristoma Blain- ville), Mauritius, Recent. The shells of this group are small, slender, and suiistral, with small apertures and usually beaded sculpture. They are primarily a warm-water group, though some species venture into cool temperate waters. Triphora pedroana (Bartsch) Triphoris pedroanus Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 250, pi. 16, fig. 1, Dec. 12, 1907. Trifora pedroana Bartsch, DaU. U. S. Nat. Mus., Bull. 112, p. 142, 1921. Pleistocene: Upper San Pedro series at the lumber yard, San Pedro, Los Angeles County (Bartsch). Recent: San Pedro, California, to South Coronado Island, Mexico, just south of Point Loma (DaU). Triphora carpenteri (Bartsch) "Triforis adversa Montagu," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 628, in part, 1864, probably not of Montagu; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 290, 1903. Triphoris carpenteri Bartsch, Proc. U. S. Nat. Mus,, Vol. 33, p. 252, pi. 16, fig. 16, 1907. Trifora carpenteri Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 142, 1921. Pleistocene: Lower San Pedro series of Deadman Island, Los Angeles County, "one imperfect specimen" (Arnold). Recent: Neah Bay, Washington. Triphora catalinensis (Bartsch) Triphoris catalinensis Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 253, pi. 16, fig. 18, 1907. Trifora catalinensis Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 142, I92I. Triphora catalinensis Bartsch, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Catalina Island and Laguna Beach, California. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 767 Triphora steamsi (Bartsch) Triphoris steamsi Bartsch, Proe. U. S. Nat. Mus., Vol. 33, p. 2.54, pi. 16, fig. 3, 1907. Trifora steamsi Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 142, 1921. Triphora slearnsi Bartsch, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: With the preceding species (Jordan). Recent: San Diego, California, to the Gulf of California, Mexico (Dall). Family TRICHOTROPIDAE Genus TRICHOTROPIS Sowerby, 1829 Trichotropis Sowerby, Zool. Journ., Vol. 4, p. 373, 1829; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 76, 1909. Trichotropis oregonensis (Conrad) Cancellaria ? oregonensis Conrad, Amer. Journ. Conch., Vol. 1, p. 151, 1865, refers to unnamed figure in Geol. U. S. Expl. Exped., Atlas, pi. 20, fig. 8, 1849, a reversed figure or a figure of an exterior impression in a rock. Trichotropis oregonensis Conrad, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 77, 1909. Oligocene or Miocene: Concretions from the Astoria group at .Astoria, Oregon (Dall). Trichotropis insignis Middendorff Trichotropis insignis MiddendoriT, Bull. Phys. Math. Acad. Imp. Sci. St. Petersb., Vol. 8, p. 18, 1849; Dall, in Moffit, U. S. Geol. Surv., Bull. 533, p. 46, 1913; U. S. Nat. Mus., BuU. 112, p. 148, 1921. Pliocene: Center Creek and second beach a half mile east of Nome, Alaska (Dall, in Moffit). Recent: From Bering Strait south, on the west to northern Japan, and on the east to the Aleutian Islands and Cooks Inlet, Alaska (Dall, 1921). Trichotropis kroyeri Philippi Trichotropis hroyen Philippi, Zeitsehr. f. Malakozool. for 1848, p. 175, March, 1849. Iphinoe kroyeri Philippi, Dall, Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919; U. S. Nat. Mus., Bull. 112, p. 149, 1921 Pliocene: Late Pliocene of St. George Island, Pribilof group (Dall, 1919). Recent: Arctic and Bering seas, eastward to the Shumagin Islands (Dall, 1921). Family RISSOIDAE Genus CINGULA Fleming, 1828 Cingula martjmi Dall Cingula rohusta Dall MS., Krause, Arch. f. Naturg. for 1885, p. 270, pi. 17, fig. la-h; not Cingula rohusta H. C. Lea, 1844. Cingula rohusta martyni Dall, Proc. U. S. Nat. Mus., Vol. 9, p. 306, pi. 3, fig. 9, 1886. Cingula marlyni Dall, Bartsch, Proc. U. S. Nat. Mus., Vol. 41, p. 485, 1912; DaU, U. S. Nat. Mus., Bull. 112, p. 157, 1921. Cingula rohusta Dall, Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919. Pliocene: Late Pliocene of St. George Island, Pribilof group (Dall, 1919). Recent: Bering Strait to the .Aleutians and eastward to Chignik Bay, Alaska (Dall, 1921). Genus ALVANIA (Leach) Risso, 1826 Alvania Leach MS., Risso, Hist. Nat. Eur. M6rid., Vol. 4, p. 140, 1826. Alvania pedroana Bartsch Ahmna pedroana Bartsch, Proc. U. S. Nat. Mus., Vol. 41, p. 341, pi. 29, fig. 4, 1911; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: "The type and another specimen .... are fossils and came from sand rock, San Pedro, Cali- fornia" (Bartsch); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). 768 San Diego Society of Natural History [Memoirs Alvania montereyensis Bartsch Alvania montereyensis Bartsch, Proc. U. S. Nat. Mus., Vol. 41, p. 343, pi. 30, fig. 2, 1911 ; Dall, U. S. Nat. Mus., Bull. 112, p. 159, 1921; T. S. Oldroyd, Proc, U. S. Nat. Mus., Vol. 65, Art. 22, p. 17, 1925. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los Angeles County (T. S. Oldroyd). Recent: Sitka, Alaska, to Monterey, California (Dall). Alvania fossilis Bartsch Alvania fossilis Bartsch, Proc. U. S. Nat. Mus., Vol. 41, p. 349, pi. 31, fig. 8, 1911. Pleistocene: Sand rock, San Pedro (Bartsch). Alvania acutilirata (Carpenter) Rissoa acutilirata Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 656, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 217, 1866; Baker, NautUus, Vol. 16, p. 41, 1902; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 305, pi. 4, fig. 12, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908. Alvania acutilirata Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 41, p. 352, pi. 31, fig. 3, 1911; Dall, U. S. Nat. Mus., BuU. 112, p. 159, 1921; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pliocene: "Pico" formation near Ventura (Waterfall); Bath-house Beach, Santa Barbara (Berry). Pleistocene: Old irrigation ditch at Ventura (Arnold); "Saugus" formation near Ventura (Waterfall); upper San Pedro series of San Pedro (Arnold). Recent: San Diego, California, to San Martin Island, Lower California, Mexico (Baker). Alvania purpurea Dall Alvania purpurea Dall, Amer. Journ. Conch., Vol. 7, p. 116, 1872; Bartsch, Proc. U. S. Nat. Mus., Vol. 41, p. 353, pi. 31, fig. 1, 1911; DaU, U. S. Nat. Mus., Bull. 112, p. 159, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to San Martin Island, Lower California, Mexico (Dall, 1921). Alvania aequisculpta Keep Alvania xquisculpta Keep, West Coast Shells, p. 65, 1888; Bartsch, Proc. U. S. Nat. Mus., Vol. 41, p. 358, pi. 32, fig. 7, 1911; Dall, U. S. Nat. Mus., Bull. 112, p. 159, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art 22, p. 17, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Rissoa seguisculpta Carpenter, Baker, Nautilus, Vol. 16, p. 41, 1902. Rissoa {Alvania) grippiana DaU, Nautilus, Vol. 21, p. 136, 1908. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro (T. S. Oldroyd); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Catalina Island, California, to San Martin Island, Lower California, Mexico (Baker). Family RISSOINIDAE Genus RISSOINA d'Orbigny, 1840 Rissoina d'Orbigny, Voy. Amer. Merid., Vol. 5, p. 395, 1840. Type (by monotypy), Rissoina inca d'Orbigny, west coast of South America, Recent, figured by Bartsch, Proc. U. S. Nat. Mus., Vol. 49, p. 42, pi. 31, figs. 6, 8, 1915. Rissoina kelseyi (Dall and Bartsch) Rissoa kelseyi Dall and Bartsch, NautUus, Vol. 16, p. 94, 1902. Alaba oldroydi Dall, Nautilus, Vol. 19, p. 15, 1905. Rissoina kelseyi Dull and Bartsch, DaU, U. S. Nat. Mus., Bull. 112, p. 160, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 17, 1925. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd). Recent: San Pedro, California, to the Coronado Islands, Lower California, Mexico (DaU, 1921). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 769 Rissoina pleistocena Bartsch Rissoi7ia pleistocena Bartsch, Proc. U. S. Nat. Mus., Vol. 49, p. 54, pi. 32, fig. 2, 1915. Pleistocene: "The type and another specimen . . . come from the lower Pleistocene of San Diego" (Bartsch), probably upper Pleistocene. Rissoina dalli Bartsch Rissoina dalli Bartsch, Proc. U. S. Nat. Mus., Vol. 49, p. 59, pi. 33, fig. 2, 1915; Dall, U. S. Nat. Mus., Bull. 112, p. 160, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925. Pleistocene: Lower Sau Pedro series of Nob Hill cut, San Pedro (Oldroyd). Recent: San Pedro, California, to South Coronado Island, Lower California, Mexico (Dall). Family TURRITELLIDAE Genus TURRITELLA Lamarck, 1799 Turritella Lamarck, Mem. Soc. Hist. Nat. Paris, Ser. 1, Vol. 1, p. 74, 1799, sole species Turbo terebra Linnaeus; Buc- quoy, Dautzenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 1, pt. 1, fasc. b, p. 224, 1884; Tryon, Man. Conch., Ser. 1, Vol. 8, pp. 192-209, 1886; DaU, U. S. Geol. Surv., Prof. Paper 59, p. 78, 1909; Cossmann, Ess. Paleo. Comp., Vol. 9, p. Ill et seq., 1912; Guillaume, BuU. Soc. G6ol. France, Ser. 4, Vol. 24, pp. 281-311, pis. 10 and 11, 1924. Turriiellus Montfort, Conchyl. Syst., Vol. 2, pp. 210-212, figure, 1810, type, Turritella terebra Lamarck (i. e., of Lin- nsEus as Turbo). Type (by monotypy), Turritella terebra (Linnaeus), Syst. Nat., Ed. 10, p. 766, 1758; figured by Reeve, Conch. Icon., Vol. 5, Turritella, sp. 3, pi. 1, fig. 3, 1849, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 195, pi. 59, figs. 32, 33, 1886, etc. Geologic range: Mesozoic to Recent. Distribution: World wide, abundant in warm seas. This well-known and widely-distributed genus' dates back at least as far as the Aptien (Lower Cretaceous) and possibly further. It is abundantly represented in the Tertiary. Mesalia Gray- differs from Turritella in its large apical angle and slightly developed anterior canal, which is absent on Turritella. Mesalia dates from the Cre- taceous and is represented in the lower Eocene of California by Turritella 7nartinezensis Gabb.^ Mathilda* Semper differs from Turritella in its heterostrophus nucleus. Arcotia Stoliczka,^ based upon a Cretaceous species of India, has a large apical angle and pre- sumably straight growth lines. A number of names have been proposed for subdivisions of Turritella, s. I., based originally on differences in sculpture, but which do not permit of a natural grouping of the species unless correlated with the characters of the outer lip as reflected in the growth lines. B. Watson in the Challenger Report called attention to the importance of the sinuation of the outer lip, and Donald briefly discussed this feature and used it partly in differentiating her new section Colpospira.^ In 1924, Guillaume published his « 1 Recently a number of "new genera" have been split off from Turritella. The significance and value of the "new genera" is yet to be shown. 2 Synop. Cont. Brit. Mus., Ed. 44. p. 61, 1842, type Ceriihium Afesal Adanson = Mesalia brevialis (Lamarck), designated by Gray, Proc. Zool. Soc. London for 1847, p. 155, 1847. » Geol. Surv. Calif., Palaeo., Vol. 2, pp. 169, 228, pi. 28, fig. 51, 1868-9. '■Mesalia" lincolnensis Weaver, 1916, from the Oligocene of Wash- ington, is an Acrilla (in the EpiUmiidx), fide Stewart, 1927. The type of Acrilla is Scalaria acuminata Sowerby. < Semper, Journ. de Conchyl., Vol. 13. p. 330, 1865. ^ Mem. Geol. Surv. India, Paleontologia Indica, "Cret. Gastr. So. India," p. 212, 1868, type, by original designation, Arcotia indica Stoliczka, p. 215, pi. 16, fig. 12, pi. 19, fig. 6, 1868. ^ J. Donald, Proc. Malac. Soc. London. Vol. 4, no. 2, p. 51, Augxist, 1900: type of Colpospira, by original designation, Turritella runcinata Watson, pi. 5, figs. 7, 7a. 770 San Diego Society of Natural History [Memoirs important "Essai sur la Classification des Turritelles," in which the characters of the growth strise are used for the recognition of five groups of Turritella. The reader is referred to this paper for what may prove to be a natural subdivision of a rather homo- geneous group.' Section Haustator Montfort, 1810 Haustator Montfort, Conchyl. Syst., Vol. 2, pp. 182-184, 1810; Guillaume, Bull. Soc. Geol. France, Ser. 4, Vol. 24, pp. 282, 290, 1924. Type (by original designation) Haustator gaUicus Montfort = Turritella imbricataria Lamarck, Eocene of Paris Basin; figured by Montfort. Like Turritella, s. s., but the growth lines having two points of inflection which are both quite near the sutures. Geologic range: Cretaceous to Recent. This section differs from the "groupe de T. hybrida Desh." in that the points of inflection of the growth lines are nearer the sutures. The sculptural characters (profiles of the whorls) appear to have a series of variations independent of the growth-line characters. Turritella jewettii Carpenter Plate 24, Figures 26, 27 Turritella jewetlii Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, pp. 539, 655, 1864, reprinted in the Smithsonian Misc. Coll., No. 252, 1872; Carpenter, Ann. Mag. Nat. ffist., Ser. 3, Vol. 17, p. 276, April, 1866; Gabb, Geol. Surv. Calif,, Palaeo., Vol. 2, p. 80, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 269, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 300, pi. 4, fig. 13, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 546, pi. 51, fig. 15, 1907; McLaughlin and Waring, Map folio accompanying Bull. 69, Calif. St. Mining Bureau, pi. 1, fig. 50, 1914; Dall, Bull. 112, IT. S. Nat. Mus., p. 151, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, no. 7, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 54, 1927. "Turritella sanguinea Reeve," Cooper, Calif. State Mining Bureau, Bull. No. 4, p. 32, 1894. Type specimen: In the U. S. National Museum. Type locality: Santa Barbara, Pleistocene or upper Pliocene. Pliocene: San Diego well, Balboa Park, San Diego (Dall); "neighborhood of Santa Barbara .... two miles from the coast, and 150 feet high" (Carpenter, 1864, may be Pleistocene); San Pedro and vicinity, common (Arnold, 1903). Pleistocene: Lower and upper San Pedro series of San Pedro and vicinity, rarer than in the Pliocene, Los Angeles County (Arnold, 1903). Recent: Santa Barbara, California, to Salina Cruz, Mexico (Dall, 1921). This species has rather flat whorls sculptured by a few spiral cords which are variable in their strength and disposition. The apical angle is greater than that of cooperi and the suture is very little or not at all depressed, sometimes rather indistinct. A common variant in the Pleistocene has two rather prominent spiral bands on each whorl, one adjacent to each suture. Some specimens show a minute nodosity on one or more of the spiral cords. Fine spiral threads are sometimes present just above the suture. A de- scription of the many sUght variations of sculpture would be useless, since they appear to occur sporadically, so far as we have observed in a brief study, and cannot be correlated with stratigraphic or geographic occurrence. » Mr. Charles Merriam at the University of California is making a study of the Turritellas, and in view of the forthcoming publication of his results, it is unnecessary to discuss the genus further here. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 771 Turritella jewettii does not appear to intergrade with T. cooperi in the PHocene, but probably descended from a common prototype earlier than the upper Miocene. Its ancestor is Turritella freya Nomland, a strikingly similar form in the upper Miocene. T. jewettii is much less common as a fossil than T. cooperi. Turritella jewettii Carpenter subspecies freya Nomland Turritella freya Nomland, Univ. Calif. Publ. GeoL, Vol. 10, p. 312, pi. 19, fig. 2, 1917. Type specimen: In the collection at the University of California, No. 11,313. Type locality: Coalinga district, California; U. Miocene. "Shell tapering rapidly, number of whorls unknoA\ia; with distinct, slightly impressed suture. Whorls fiat with a wide ridge near middle ; immediately above the suture are two prominent spiral cords with interspaces of about the same wddth; between the middle ridge and suture above, a slight tendency to depression is noticeable; ridges and interspaces covered by numerous, on the type twenty-five, narrow spiral striations; incremental lines indistinct. Aperture subcircular to nearly square. Dimensions: Maximum diameter, 16 mm.; height unknown." Miocene: Upper Miocene (Santa Margarita formation) of Coalinga district; also in type section of the Santa Margarita formation about a half mile north of the town of Santa Margarita, San Luis Obispo County, California. This Turritella is so close to T. jewettii Carpenter that it can scarcely be regarded as more than a subspecies of the previously named form. The apical angle is identical with that of jewettii and the sculpture is similar to the sculpture of many Pleistocene specimens of Carpenter's typical form, except that freya appears to have numerous fine spiral threads, whereas typical jewettii has either very few or none. Nomland also described Turritella margaritana from the Santa Margarita formation, but the type specimen is so poorly preserved that little can be determined in regard to its relationships. Turritella cooperi Carpenter Plate 24, Figures 28-34 Turritella cooperi Carpenter, Brit. .\ssn. Adv. Sci., Rept. for 1863, pp. 612, 655, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 216, 1864; Gabb, Geo). Surv. Calif., Palaeo., Vol. 2, p. 80, 1868-9; Tryon, Man. Conch., Ser. 1, Vol. 7, p. 200, pi. 61, fig. 61, 1886; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 269, 1888; Keep, West Coast Shells, p. 73, fig. 58, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 205, 1892; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 318, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 300, 1903; Keep, West .American Shells, p. 215, fig. 231, 1904; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 546, pi. 51, fig. 14, 1907; Bull. 309, U. S. Geol. Surv., pi. 41, fig. 14, 1907; English, Univ. Calif. Publ. GeoL, Vol. 8, p. 211, 1914; Dall, Bull. 112, U. S. Nat. Mus., p. 152, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 11, p. 16, 1925; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 3, p. 65, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Turritella cooperi Carpenter var. fernandoensis .Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 538, pi. 51, fig. 13, 1907; Bull. 309, U. S. Geol. Surv., pi. 41, fig. 13, 1907. Turritella nova Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 208, pi. 11, fig. 3, 1916. Shell with high, many-whorled spire; suture depressed; whorls somewhat ventricose, with spiral ridges or cords which vary widely in number and character, frequently consisting of two rather prominent carina which trisect the area of the whorl. Large Pleistocene specimens measure 65 mm. in length, with the body whorl 17 mm. in diameter. Type specimens: Of cooperi, in the collection at the University of California, jide Oldroyd, 1927; oi fernandoensis, in the U. S. National Museum, No. 164,957; of nova, in the collection at the University of California. 772 San Diego Society of Natural History i Memoirs Type localities: Of cooperi, San Pedro, California, Recent, fide Oldroyd, 1927; of fernandoensis, Elsmere Canyon, Los Angeles County, lower Pliocene; of nova, Waltham Canyon, Fresno County, Pliocene. Pliocene: S. D. S. N. H. localities 201, 203, 204, 206, 208, 215, 216, lower Pliocene of Elsmere Canyon and east of Fernando Pass, Ix)s Angeles County (coll. by H. R. Gale); "Lower Fernando" of Elsmere, Holser, and Pico canyons, Los Angeles County (English, 1914); San Diego well, Balboa Park, San Diego (DaU) ; "Russ School" San Diego (Arnold, 1903) ; S. D. S. N. H. localities 213, 214, middle Phoeene west of Fernando Pass, Los Angeles County (coU. by H. R. Gale) ; S. D. S. N. H. localities 217, 217a, 217b, middle Pliocene of Holser Canyon, Los Angeles County, common (H. R. Gale, coll.); upper Pliocene north of city of Ventura (Waterfall, 1929); S. D. S. N. H. loc. 151, one and a half miles northeast of Goleta, upper Pliocene ?, Santa Barbara Coimty (Van Court Warren). Pleistocene: "Pliocene" of Deadman Island and lower San Pedro series of Deadman Island and San Pedro bluffs, Los Angeles County (Arnold, 1903); lower San Pedro fauna of Nob Hill cut, at San Pedro (Oldroyd, 1925) ; Pleistocene of Barlow's Ranch and the irrigation ditch north of Ventura, Ventura County (Arnold); S. D. S. N. H. loc. 233, Las Posas zone north of Arroyo Santa Rosa, Ventura County, common (U. S. G., coll.); S. D. S. N. H. loc. 244, lower part of the Las Posas zone in Sexton Canyon, Ventura County, not common (U. S. G., coll.); lower Quaternary at Magdalena Bay, Lower California, Mexico (E. K. Jordan, 1924) ; upper San Pedro series (Palos Verdes forma- tion) of Crawfish George's, Los Cerritos, Lumber Yard, and Deadman Island (Arnold, 1903) ; Pleisto- cene of Pacific Beach, San Diego County (Arnold, 1903); San Quintin Bay, Lower California, Mexico (DaU, 1892). Recent: Monterey to San Diego, California (DaU, 1921). This species occurs at a considerable number of localities, sometimes in great abun- dance, only a few of the localities being recorded in the list given above. In the Recent fauna live specimens are seldom collected. The most common Pleistocene form of this species has two carinse on each whorl, which divide the side of the whorl into three parts. Sometimes these carinse are slightly nodulose; sometimes interribs appear in more or less prominence; and other combina- tions of characters occur, which in isolated specimens appear to indicate varietal differ- ences, but which are clearly only individual idiosyncrasies. In the middle and lower Pliocene these variants from the common Pleistocene form become more common but occur along with the typical form. The form having two or three interribs equal in strength to the two main carinae Arnold named variety fernandoensis, while the form with the two carinse well developed and separated by a narrow groove has been named nova. The characters upon which these names have been founded appear to intergrade and intermingle at several different localities and horizons and do not appear to warrant varietal distinctions. Turritella mariana Dall,^ a very slender shell described from west Mexican waters, appears to be closely related. We have not seen Dall's type, but specimens of cooperi from the lower Pliocene east of Fernando Pass (S. D. S. N. H. loc. 216) appear to agree rather closely with Ball's figure and description. Turritella vanvlecki Arnold appears to be closely related but distinct. It is characterized by having several spiral threads on the whorls and a carina-like spiral in about the middle of the whorl. This form occurs with cooperi in the middle Pliocene of Holser Canyon, but the two forms do not seem to intergrade. > Bull. Mus. Comp. Zool. Harvard College, Vol. 43, no. 6, p. 327, pi. 11, fig. 14, October, 1908; type locality, near Tres Marias Islands. Mexico, Recent, in 80 fathoms, rocky bottom. VoLiME I ] Pliocene and Pleistocene Mollusca of California 773 Tunitella vanvlecki Arnold Plate 24, Figure 22 Turrilella vandecki Arnold, U. S. Geol. Surv., Bull. 396, p. So, pi. 22, fig. 3, January 15, 1910; Bull. 398, pi. 44, fig. 3, 1910; Nomland, Univ. Calif. Publ. Geol., Vol. 10, pi. 12, fig. 5, 1917. Type specimen: In the U. S. National Museum, No. 165,496. Type locality: Anticline Ridge, northeast of Coahnga, Cahfoniia; lower Pliocene. Pliocene: Anticline Ridge, northeast of Coalinga; three miles north of Bradley, Monterey County; "near the base of the Etchegoin formation" (Arnold, 1910); Etchegoin Pliocene of Coalinga district (Nomland, 1917); S. D. S. N. H. localities 217a, 2176, middle Pliocene of Holser Canyon, Los Angeles County, five specimens (H. R. Gale, coll.). The general appearance of this species is much like that of T. cooperi Carpenter, but typically the sculpture consists of five spiral ribs, with smaller interribs between, the middle primary being accentuated and carina-like. The suture is deeply impressed. The specimen herewith figured, however, has the basal spiral also accentuated, and the suture not impressed below the inward slope of the upper part of the whorl. While Turrilella cooperi in the Pliocene has considerable variations in sculpture, its two carina- like ribs equidistant from the center of the whorl are generally well developed (attaining their greatest prominence in the form nova of Nomland and perhaps also in jnariana Dall), whereas vanvlecki has one accentuated spiral riblet that occurs approximately in the middle of the whorl. In the form fernandoensis Arnold, the spiral riblets are small and all approximately of equal size. In the collections available for study we have seen no specimens intermediate between cooperi and vanvlecki, and consequently we have considered the latter specifically distinct. More material, however, may show it to be but a variety. Turrilella vanvlecki Arnold is placed in the section Hauslator tentatively, since none of the specimens examined show the growth lines with sufficient clearness to determine the sectional characters. If the species is as closely related to T. cooperi as specimens at hand seem to indicate, it should unquestionably be placed in that section. Section Undetermined The following species are not allocated to any section in this paper because their sectional characters have not been sufficiently studied. Tunitella goniostoma Valenciennes Tvrritella goniostoma Valenciennes, Humboldt and Bonpland's Voy. Reg. Equin. Nouv. Cont., Pt. 2, Zoologie, Vol. 2, liv. 14, p. 275, 1832; Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 10, Turrilella, pp. 21, 22, pi. 10, figs. 1, 1844; Reeve, Conch. Icon., Vol. 5, Turritella, sp. 10, pi. 3, figs. 10a, 10b, 1849; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 198 (in part), pi. 60, fig. 51, pi. 61, figs. ? 54, 55, 1886; Stearns, Proc. U. S. Nat. Mus., Vol. 14, p. 326, 1891; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pt. 5, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. Pliocene: Santa Anita Point, also Coronados Island and Carmen Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, and upper Quaternary at Scammons Lagoon, Lower California, Mexico (Jordan). Recent: Scammons Lagoon, Lower California, Mexico (Hemphill coU.), to Peru. A discussion of the synonymy of this species will not be attempted here. Most authors who have been in a position to know remark upon the variability; but until abundant material is critically compared with the types or original descriptions and 774 San Diego Society of Natural History [ Memoirs figures of several closely related supposed species of the west Mexican waters, any conclusions in regard to synonymy are premature. The species has been well figured and described by Kiener, who states that Valenciennes described it from a young indi- vidual. Specimens from the Pleistocene of Magdalena Bay agree with Kiener's figures. A rather common form has flat whorls with an indistinct linear suture on the earlier whorls and the later whorls protruding somewhat near the deeply depressed suture. Numerous spiral threads with minute intercalated threadlets cover most of the surface of the whorls where erosion has not been too vigorous. This appears to be the common form in the Magdalena Bay Pleistocene and is not uncommon in the Recent fauna of Lower California. Turritella tigrina Kiener Turritella tigrina Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 10, Turrilella, p. 29, pi. 4, figs. 2, 1844; Reeve, Conch. Icon., Vol. 5, Titrrilella, sp. 10, pi. 3, fig. 8, 1849; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 199, pi. 62, fig. 65, 1886. Turrilella cumingii Reeve, Conch. Icon., Vol. 5, sp. 13, pi. 4, fig. 13, 1849; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 199, pi. 62, fig. 66, 1886. Pleistocene: Coast of Oaxaca, Me.\ico (coll. by R. H. Palmer). Recent: Cedros Island (?), Lower California, Mexico, to Panama. This species is rather high spired, of about twenty whorls, which are flat sided and obtusely angulated or carinated on the lower part just above the suture. The sculpture consists of about ten spiral cords, usually about eight above the carination, often alter- nating in strength and with intercalated threadlets. The color of Recent specimens is whitish with irregular patches of chestnut or chocolate color. It has been suggested that this species is conspecific with T. leucostoma Valenciennes, described in 1832. T. cumingii Reeve appears to be a synonym. Turritella imperialis Hanna Turritdla imperialis Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 457, pi. 21, figs. 1, 2, 3, 1926. Type specimen: In the collection at the University of California. Type locality: In a branch of Alverson Canyon, Coyote Mountain, Imperial County, California, Lower Pliocene. This is a high-spired species with a depression at the suture and another in the middle of the whorl. This produces a sculpture consisting of two prominent spiral ribs, slightly noded in some specimens. This species has only been reported from the Imperial formation of Coyote Mountain, from which Hanna has recorded a number of specimens. It appears, as pointed out by Hanna, that T. imperialis is related to certain Atlantic coast Turritellas. It is like T. inezana Conrad, of the lower Miocene of California, with the spiral ribs accentuated.' Turritella nodulosa King and Broderip Turritella nodulosa King and Broderip, Zool. Journ., Vol. 5, p. 347, 1832; Reeve, Conch. Icon., Vol. 5, Turritella, sp. 11, pi. 4, figs, lla-b, 1849; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 202, pi. 63, figs. 78, 79, 80, 1886; Zetek, Mol. Repub. Panama, p. 31, 1918; Dall, Nautilus, Vol. 32, p. 24, 1918; not T. nodulosa von Muenster, Beitr. zur Petref., 1841. Turritella papillosa Kiener, Spec. G6n. Icon. Coq. Viv., Vol. 5, Turritella, p. 31, pi. 14, fig. 3, 1844; re-figured by Tryon, op. cit., pi. 63, fig. 80. ' Called to our attention by Mr. William Corey and Dr. W. P. Woodring. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 775 Pleistocene: Magdalena Bay, Lower California, Mexico (Dall). Recent: West Mexican coast to Panama. This species is of medium size, forty or fifty millimeters in length, consisting of fourteen or fifteen whorls. A common form has a prominent nodose carina in the middle of the whorl with about nine spiral threads above and ten or eleven below. It has a second, usually much less prominent carina below, next to the suture, and some authors state that this carina becomes on some specimens of equal prominence to the upper one, causing an obtusely bicarinate whorl profile. Living specimens are light yellowish- brown with chestnut maculations. According to Kiener's figure, T. papillosa appears to be a synonym. A number of large Turritellas have been described from the Miocene formations of California and Lower Calif orma. TurriteUa inezana Conrad,' characteristic of the Vaqueros formation (lower Miocene of California), is probably an immigrant species, as it appears to have no direct ancestor in the earlier Tertiary of the region. It is a high-spired species with flat-sided whorls obtusely or obscurely carinated on each side of the suture. A form with the whorls convexly inflated Wiedey has named variety pertumida.- TurriteUa ocoyana Com-ad,' of the Temblor fauna (lower middle Miocene) of California, belongs to the typical section of TurriteUa. It also is an immigrant, but is sectionally distinct from inezana. TurriteUa ocoyana appears to be quite variable in strength of spiral sculpture, grading from the acutely keeled forms, which were named TurriteUa bosei by Hertlein and Jordan,^ to the ventricose, obscurely carinated forms named T. wittichi by the same authors. The former name is probably a synonym of ocoyana, while the latter represents a more extreme variant and might be retained in a varietal sense, its final disposition depending upon a study of large collections. Wiedey,^ however, has considered T. wittichi a synonym of ocoyana. T. temblorensis Wiedey (1928) is another variety of ocoyana. In the Peruvian Miocene the ocoyana clan is represented by TurriteUa abrupta Spieker (T. robusta Grzybowski, 1899, not T. robusta Gabb, 1864, + T. charana Spieker, 1922, -|- T. supraconcava Hanna and Israelsky, 1925, -|- T. robusta fredeai Hodson, 1926), which is a larger and more coarsely sculptured form.* Genus TURRITELLOPSIS G. O. Sars, 1878 Turrilellopsis G. O. Sars, Moll. Reg. Arct. Norv., p. 186, 1878; Tryon; Man. Conch., Ser. 1, Vol. S, p. 193, 1886. Shell like that of TurriteUa, the whorls of the spire grooved across ; aperture oval ; radula without marginal teeth. Inhabits boreal seas. (Tryon.) Type (by monotypy), Turritelopsis acicula (Stimpson), north Atlantic, Recent. ' Pac. R. R. Repts., Vol. 7. p. 175, pi. 8, fig. 4, 1857. Santa Inez Mountains. Wiedey (Trans. San Diego Soc. Nat. Hist.. Vol. 5. pp. 120, 121, 1928) discussed this species but believed T. variata Conrad occurred with it. Woodring (Trans. San Diego Soc. Nat. Hist., Vol. 6, p. 160- 1930) conchiHed the latter species was of upper Eocene age. ' Op. cil. Vol. 5, no. 10, p. 119. pi. 12, figs. 1, 6. 1928. » U. S. Pac. R. R. Repts., Vol. 5, p. 329. pi. 8. figs. 73, 73a-6, 1856; re-figured by Wiedey, op. eit.. pi. 10, figs. 2, 4, 9. ' Proc. Calif. Acad. Sci., Ser. 4, Vol. 16. p. 634, pi. 21, figs. 1, 2, 1927. ' Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 120, 1928. 6 Woodring has recently given an excellent short discussion of the ocoyana "phylum" of Turritellas: vide Carnegie Inst., Publ. No. 385, pp. 95. 96 and footnote, 1928. 776 San Diego Society of Natural History [Memoirs Turritellopsis acicula (Stimpson) variety stimpsoni Dall "Turrilellopsis acicula Stimpson" G. O. Sars, Moll. Reg. Aret. Norv., p. 186, pi. 10, figs, l-la-6, 1878; not Turritella acicula Stimpson, Shells of New England, p. 35, pi. 1, fig. 5, 1851. Turritellopsis acicvla stimpsoni Dall, Proe. U. S. Nat. Mus., Vol. 56, p. 347, 1919; U. S. Nat. Mus., Bull. 112, p. 152, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 59, 1927. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Nunivak Island, Alaska, to San Diego, California, circumboreal (Dall, 1921). Genus TACHYRHYNCHUS Morch, 1868 Tachyrhynchus Morch, Amer. Journ. Conch., Vol. 4, p. 46, June 4, 1868. Tach3rrhyiichus lacteolus (Carpenter) variety subplanatus (Carpenter) Mesalia subplanata Carpenter, Proc. Acad. Nat. Sci. Phila. for 1865, p. 62. Tachyrhynchus lacteolus subplanatus Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 152, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 58, 1927. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Puget Sound to San Diego, California (Dall). This shell looks like some species of Bittium but it is supposed to have a multispiral operculum with central nucleus, whereas Bittium has a paucispiral operculum. Family VERMETIDAE Shell tubular, septate within, attached or free; sometimes regularly spiral when young, always becoming irregular in adult growth; aperture rounded, usually entire, sometimes fissured; operculum corneous, annular, sometimes spiral, rarely absent. (Tryon.) For discussions of the Vermetidce the reader is referred to the review of the family by Morch' and to the monograph by Tryon.^ Genus VERMICULARIA Lamarck, 1799 Vermicularia Lamarck, Mem. Soc. ffist. Nat. Paris, Vol. 1, p. 78, 1799; Syst. .\nim. s. Vert., p. 97, 1801; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 168, 1886. Type (by monotypy), Serpula lumbricalis Linnaeus, figured by Tryon, op. cit., p. 186, pi. 55, fig. 98, 1886, Indo-Pacific, Recent. Shell free, in its early stage regularly coiled like a Turritella; subsequently imcoiled, the tube variously twisted or more or less straight and prolonged; operculum size of the aperture. Tropical and subtropical. (Tryon.) Vermicularia ebumea (Reeve) Vermetus ebumeus Reeve, Conch. Syst., Vol. 2, p. 46, pi. 152, fig. 2, 1842; Proc. Zool. Soc. London, Pt. 10, p. 197, February, 1843; Carpenter, Proc. Zool. Soc. London for 1863, p. 358, 1863; Brit. .\ssn. Adv. Sci., Rept. for 1863, p. 556, 1864. "VerTnetus glomeratus ? Lamarck," C. B. Adams, Ann. Lye. Nat. Hist. New York, Vol. 5, p. 216 (of separate), 1852, not of Lamarck. Vermetus {Vermicularia) pellucidus Broderip and Sowerby, var. eburneus Reeve, Tryon, Man. Conch., Ser. 1, Vol. S, p. 188, pi. 56, fig. 6, 1886. Vermiculus fewkesi Yates, Santa Barbara Soc. Nat. Hist., Bull. No. 2, p. 48, pi. 2, figs. 8, 9, August, 1890. I Review of the Vermetidx. Proc. Zool. Soc. London for 1861, pp. 145-181, pi. 25, and pp. 326-365, 1861. « Man. Conch., Ser. 1, Vol. 8. 1886. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 777 Vermicularia eburnea Reeve, Dall, U. S. Nat. Mus., Bull. 112, p. 150, 1921; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 460, 1926; Oldroyd, Stanford Univ. Pubi. Geol., Vol. 2, Pt. 3, p. 49, 1927. Type locality : South America ( fide Oldroyd) . Pliocene: Coyote Mountain, Imperial County, California (Hanna). Recent: San Pedro, California, to Panama (Dall); South ^\merica. Vermicularia (?) nodosa (T. S. Oldroyd) Vermetus nodosus T. S. Oldroyd, Nautilus, Vol. 34, p. 116, pi. 5, fig. 10, April, 1921. Type specimen: In the Oldroyd Collection at Stanford University. Type locality: Nob Hill cut, San Pedro, Pleistocene. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los Angeles County (Oldroyd). Oldroyd described this shell as follows: "Shell a fragment; length 46 mm.; breadth 11 mm.; smooth and perfectly round and curved, septate within. The specimen has three large pear-shaped nodes, two of which are opposite each other, over the septum, one length- wise of the shell, and the other crosswise." Genus ALETES Carpenter, 1856 Aletfis Carpenter, Proc. Zool. Soc. London, Part 24, p. 226, 1856i; Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 301, 1855-57; Tryon, Man. Conch., Ser. 1, Vol. 8, pp. 165, 174, 1886. Type (by monotypy), Aletes squamigerus Carpenter. Shell spirally twisted, attached, surface often decussated, columella with a faint median thread- like Hne. Aletes squamigerus Carpenter Aides squamigerus Carpenter, Proc. Zool. Soc. London for 1856, p. 226, 18.56; Dall, LT. S. Nat. Mus., Bull. 112, p. 151, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 49, 1927; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 253, 254, 255, 1929. Ver7netus {Thylacodes) squamigerus Carpenter, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 181, pi. 54, figs. 73, 74, 1886. Serpidorhis squamigerus Carpenter, Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 264, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 299, 1903. Vermetus squamigerus Carpenter, E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919. Type locality: Santa Barbara, California, Recent. Pleistocene: Santa Barbara to San Diego (Cooper); rare in lower San Pedro series of Deadman Island and San Pedro; common in upper San Pedro series of San Pedro and vicinity (Arnold); chiton bed on Point Firmin, near San Pedro (Chace); palisades of Santa Monica (coll. of F. C. Clark); Pacific Beach, Point Loma, and two miles north of Del Mar, San Diego County (Stephens) ; San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Payta, Peru, and the Galapagos Islands (Dall). Aletes squamigerus Carpenter variety permatus (Morch) Plate 24, Figure 5 Stephopoma pennatum Morch, Journ. de Conchyl., Ser. 2, Vol. 4, p. 43, 1860; Proc. Zool. Soc. London for 1861, p. 151, pi. 25, figs. 3, 4, 5 (sheU), 6, 7 (operculum), 8 (spine of operculum), 1861. Aletes squamigerus pennatus Morch, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925. Pleistocene: Lower San Pedro of Nob HiU cut, San Pedro, Los Angeles County, "plentiful" (Oldroyd). Recent: West coast of Mexico and Panama ? This variety lacks the rough longitudinal striations of the typical form. 1 In the Zoological Society ProceedingB for 1856, Carpenter refers to his Mazatlan Catalogue, p, 301, hence the latter must have been at least in page proof at that time. But since the title page gives the dates "1855-57," we have assumed for the time being that its actual date of issue was 1857. 778 San Diego Society of Natural History [Memoirs Genus SPIROGLYPHUS Daudin, 1800 Spiroglyphus F. M. Daudin, Rec. Mem. Moll., p. 39, 1800; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 166, 1886. Type, Spiroglyphus annulatus Daudin, 1800, figured by Tryon, op. cit., p. 178, pi. 51, figs. 51, 52, 1886. Aiiimal excavating a groove on the surface of shells or stones, covering it over with shelly material, thus formmg a tuliular planorbiform case. When first hatched, the shell is spiral and regular, consisting of one and a half whorls. Operculum large, thick, convex exteriorly, with strong concentric laminse, plane interiorly, concentrically lirate, with central mamilla, and narrowly elevated margin. (After Trj-on.) Spiroglyphus lituella (Morch) Siphoniitm (Dendropoma) lituella Morch, Proc. Zool. Soc. London for 1861, p. 154, 1861. Spiroglyphus lituella Morch, Carpenter, Brit. Assn. Adv. Sei., Rept. for 186.3, p. 654, 1864; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 299, 1903. Vermelus (Siphonium) lituella Morch, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 183, pi. 54, fig. 82, 1886. Spiroglyphus lituellus Morch, Dall, U. S. Nat. Mus., Bull. 112, p. 151, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 50, 1927. Pleistocene: Upper San Pedro series of San Pedro, Deadman Island, Crawfish George's, and Los Cerritos, Los Angeles County, "common on stones and shells" (Arnold). Recent: Forrester Island, Alaska, to San Diego, California (Dall). Genus PETALOCONCHUS Lea, 1843 Petaloconchus H. C. Lea, Trans. Amer. Philos. Soc, New Series, Vol. 9, p. 233, 1843; Tryon, Man. Conch., Ser. 1, Vol. 8, pp. 165, 172, 1886; Woodring, Carnegie Inst., Publ. No. 385, p. 347, 1928. Type (by monotypy), Petaloconchus sculpturatus Lea, figured by Tryon, Struct. Syst. Conch., pi. 67, fig. 76, 1883. Shell more or less regularly coiled in an open spire durmg part of growth, more or less straight durmg final stage. Early stage contorted or more regularly coiled. Aperture circular. Columellar wall bearing two relatively long, thin lamelliE that disappear near aperture and may be absent elsewhere. Sculpture consisting of spirally arranged crude pustules or of axial ribs. (Woodring.) Petaloconchus anellum (Morch) Vermetus anellum Morch, Proc. Zool. Soc. London for 1861, p. 359. Vermelus (Petaloconchus) anellum Morch, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 173, pi. 49, fig. 34, 1886. Vermiculum anellum Miirch, Dall, U. S. Nat. Mus., Bull. 112, p. 151, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Petaloconchus anellum Morch, Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 51, 1927. Type locality: California, on Haliotis. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Todos Santos Bay, Lower California, Me.xico (Dall). Petaloconchus complicatus Dall Petaloconchus complicatus Dall, BuU. Mus. Comp. Zool. Harvard CoU., Vol. 43, p. 326, 1908; U. S. Nat. Mus., Bull. 112, p. 151, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 3, Pt. 3, p. 52, 1927. Type specimen: In the U. S. National Museum, No. 123,035. Type locality: Near Cocos Island, Recent. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Puget Sound to Panama (Dall, 1921). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 779 Family CAECIDAE Bartsch' has proposed the following artificial key to the genera of the Family CoecidoE : Operculum conic Brochina Operculum flat or concave Sculpture absent excepting incremental lines Fartulum Sculpture not absent Sculpture of raised spiral ridges only Elephantulum Sculpture not of raised spiral ridges only Sculpture of raised spiral ridges and axial rings Elephantanellum Sculpture of axial rings only Axial rings strong and distantly spaced Coecum Axial rings slender and closely spaced Micranellum It should be noted that the axial sculpture parallels the aperture. Genus CAECUM Fleming, 1817 Caecum calif omicum Dall Csecum cooperi Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 655, 1864, not Csecum cooperi Smith, Ann. Lye. Nat. Hist. N. Y. for 1862, pp. 154, 168. Csecum californicum Dall, Proc. U. S. Nat. Mus., Vol. 8, p. 541, 1885; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 219, pi. 66, fig. 65, 18S6; Baker, Nautilus, Vol. 16, p. 41, 1902; .Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 297, pi. 8, fig. 6, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 149, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Lower San Pedro series of Deadman Island and San Pedro (Arnold) and of Nob Hill cut at San Pedro (T. S. Oldroyd); upper San Pedro series of San Pedro and Crawfish George's, "quite common" (Arnold); San Diego (Stearns, fide Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Lower California (Dall); San Martin Island, Lower California, Mexico (Baker). Caecum dalli Bartsch Csecum dalli Bartsch, Journ. Wash. Acad. Sci., Vol. 10, p. 568, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 149, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to Lower California, Mexico (Dall). Genus MICRANELLUM Bartsch, 1920 Micranellum Bartsch, Journ. Wash. Acad. Sci., Vol. 10, p. 568, December 4, 1920. Type (by original designation), C cecum crebricinctum Carpenter. Surface of the shell marked by closely spaced, slender, axial annulations; operculum thin, corneous, concave. (Bartsch.) Micranellum crebricinctum (Carpenter) Csecum crebricinctum Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 655, 1864; Proc. Calif. Acad. Sci., Vol. 3, , IM p. 215, 1865; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 218, pi. 67, fig. 71, 1886; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 300, 1892; Baker, Nautilus, Vol. 16, p. 41, 1902; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 298, ^ ■ 1903. Micranellum crebricinctum Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 149, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 45, 1927. ' Journ. Wash. Acad. Sci., Vol. 10, p. 566, 1920. 780 San Diego Society of Natural History [ Memoirs Pleistocene: Lower San Pedro series of Deadman Island and San Pedro (Arnold) and "plentiful" at Nob Hill cut, San Pedro (T. S. Oldroyd); upper San Pedro series at San Pedro and Crawfish George's, Los Angeles County (Arnold); Coronado Beach, San Diego (Dall, 1892); upper Pleistocene at San Quentin Bay, Lower California, Mexico (Jordan; Dall, 1892, record attributed to Orcutt, and age given as Pliocene). Recent: Monterey, California, to Todos Santos Bay, Lower California, Mexico (Dall, 1921); San Martin Island, Lower California (Baker). According to Dall (1892), C cecum magnum Stearns' is a synonym. M. crebricinctum is a shallow-water shell, locally quite abundant. Micranellum pedro'ense Bartsch Micrandlum -pedro'ense Bartsch, Journ. Wash. Acad. Sci., Vol. 10, p. 564, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 149, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 46, 1927. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro to San Diego, California (Dall). Genus FARTULUM Carpenter, 1858 Fartulum bakeri Bartsch Fartulum bakeri Bartsch, Journ. Wash. Acad. Sci., Vol. 10, p. 566, 1920; DaU, U. S. Nat. Mus., Bull. 112, p. 150, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Ellamar, Alaska, to Mazatlan, Mexico (Dall). Fartulum hemphilli Bartsch Fartulum hemphilli Bartsch, Journ. Wash. Acad. Sci., Vol. 10, p. 566, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 150, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 16, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, "not rare" (T. S. Oldroyd) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to Point Abreojos, Lower California, Mexico (Jordan). Fartulum occidentale Bartsch Fartulum occidentale Bartsch, Journ. Wash. Acad. Sci., Vol. 10, p. 566, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 150, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Gulf of Georgia to Lower California (Dall). Family LITTORINIDAE Genus LITTORINA Ferrusac, 1822 Liltorina Ferrusac, Tabl. Syst., pp. xi, x.\xiv, 1822; Rang, Man. MoUusques, p. 1S5, 1829; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 79, 1909; Iredale, Proc. Malac. Soc. London, Vol. 10, ]>. 223, 1912. Type (by subsequent designation, Rang, 1829, fide Dall and Iredale), Littorina littoralis. As the species of this genus are very variable, it is probable that the number of names listed below should be reduced materially by synonymizing some of those more recently proposed. I See Tryon, Man. Conch., Ser. 1, Vol. 8, p. 219, pi. 67, fig. 83, 1886. Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 781 Littorina mariana Arnold Ullonna mariana Arnold, U. S. Geol. Surv., Bull. 396, p. 86, pi. 29, fig. 1, 1910; Bull. .398, pi. 51, same figure, 1910; Nomland, Univ. Calif. Publ. Geol,, Vol. 10, p. 221, 1917. Pliocene: Upper Mya horizon, upper purt of Etchegoin formation, Coalinga district, San Joaquin basin, upper Pliocene (Arnold; Nomland). Littorina mariana Arnold variety alta Arnold LiUorina mariana var. alta Arnold, op. cit., p. 87, pi. 29, fig. 2, 1910; Bull. 398, pi. 51, fig. 2, 1910; Nomland, op. cit., p. 221, 1917. Pliocene: With the typical variety (Arnold; Nomland). This may be only an individual variation of the shorter spired typical form. Littorina palliata (Say) Turbo pallialus Say, Journ. Acad. Nat. Sci. Phila., Vol. 2, p. 240, 1822. LiUorina palliata Say, Gould, Inv. Mass., p. 260, fig. 167, 1841; Dall, U. S. Geol. Surv., Prof. Paper 12.5-C, p. 29, pi. 5, fig. 12, 1920; U. S. Nat. Mus., Bull. 112, p. 1.52, 1921. Pliocene: Prospectors' pits on the second beach, one-half to one-fourth mile east of Nome, Alaska (Dall, 1920). Recent: Atlantic (Dall, 1921). Littorina petricola Dall Littorina petricola Dall, U. S. Geol. Surv., Prof. Paper 59, p. 80, pi. 4, fig, 9, 1909; Arnold and Hannibal, Proc. Amer. Philos. See, Vol. 52, p. 594, 1913; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 93, and table opposite, 1922. Miocene: Questionably in the Empire formation, upper Miocene of Coos Bay, Oregon (Howe). Pliocene: Coos conglomerate of Fossil Rock, Coos Bay, Oregon (Dall, as Pleistocene; Howe); four miles south of Empire, Oregon (Arnold and Hannibal). Littorina remondi Gabb Littorina remondi Gabb, Geol. Surv. Calif., Pala!o., Vol. 2, p. 14, pi. 2, figs. 23, 23a, 1866, p. 80, 1868-9; Weaver, Univ. Calif. Publ. Geol., Vol. 5, p. 254, 1909; Clark, in Lawson, U. S. Geol. Surv., Folio No. 193, p. 12, 1914; Clark, Univ. Calif. Publ. Geol., Vol. 8, pp. 403, 405, 422, 425, 484, 560, pi. 65, fig. 13, 1915; Stewart, Proc. Acad. Nat. Sci. PhUa., Vol. 78, p. 346, pi. 32, fig. 5, 1927. Miocene: Kirker's Pass, Contra Costa County (Gabb, as Pliocene); San Pablo formation, upper Miocene, middle California (Clark). Littorina planaxis Nuttall in Philippi Littorina planaxis Nuttall, Philippi, Abbild. Beschr. Conchyl., Vol. 2, pt. 7, p. 201, pi. 4, fig. 16, March, 1847; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 80, 1868-9; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 248, pi. 43, fig. 55, 1887; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 246, 1888; Keep, West Coast Shells, p. 68, fig. 53, 18S8, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 301, 1903; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919. Littorina patula Gould, Otia Conch., "Expedition Shells," p. 52, 1846. Liltoi-ina planaxis Philippi, Dall, U. S. Nat. Mus., Bull. 112, p. 153, 1921, "Ldtorina" in error; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 17, 1925. Pleistocene: "Pliocene" of Deadman Island, Timms Point zone; lower San Pedro series at Deadman Island and San Pedro (Arnold); lower San Pedro series at Nob Hill cut (T. S. Oldroyd); upper San Pedro series at San Pedro (Arnold) ; chiton bed at Point Firmin (Chace) ; palisa es of Santa Monica (coll. of F. C. Clark); San Nicholas Island; San Diego (Cooper). Recent: Puget Sound to Magdalena Bay, Guadalupe and Socorro islands, Mexico (Dall). Philippi attributed this species to Nuttall with a query as to its place of publication. His description of the species appears to be the first, and to avoid confusion the name should be cited as Nuttall in Philippi. 782 San Diego Society of Natural History [Memoirs Littorina scutulata Gould Plate 32, Figures 16, 17, 18 Uttorina scutulata Gowld, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 83, 1849; U. S. E.xpl. Exped., Vol. 12, p. 200, 1852, Moll. Atlas, pi. 14, figs. 241, 241a, 1856; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 250, pi. 45, figs. 98, 99, 100, 1887; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 246, 1888; Keep, West Coast Shells, p. 68, fig. 52, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 302, 1903; E. P. and E. M. Chace, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Littorina {Mdarhape) scutulata Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 153, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 17, 1922. Type locality: Puget Sound, Recent. Pleistocene: Lower San Pedro series of Deadman Island, San Pedro (Arnold); Nob Hill cut (Oldroyd): Barlow's Ranch, near Ventura (Arnold); chiton bed at Point Firmin (Chace); Pacific Beach and Spanish Bight, San Diego (Arnold) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Kodiak Island, Alaska, to Turtle Bay and Socorro Island, Lower California, Mexico (Dall). L. lapida and plena Gould, 1849, are both synonyms. Littorina varia Sowerby Littorina varia Sowerby, Genera Shells, Littorina, No. 38, fig. 3, 1832; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 246, pi. 43, fig. 44, 1887; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 231, 1909; E. K. Jordan, BuU. So. Calif. Acad. Sci., Vol. 23, p. 156, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 449, 1926. Pliocene: Coyote Mountain, Imperial County (Hanna). Recent: Magdalena Bay, Lower California, Mexico, to Casma, Peru (Jordan). Family LACUNIDAE Genus LACUNA Turton, 1827 It is possible that there is but one, very variable species in this genus in the Cali- fornia fauna. Lacuna divaricata (Fabricius) variety solidula Loven Plate 32, Figure 19 Lacuna solidula Loven, Index Moll. Scandinavia, p. 23, 1846; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 266 in part, pi. 50, fig. 69, 1887; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 244, 1888; Dall, U. S. Nat. Mus., Bull. 112, p. 154, 1921; Strong, NautUus, Vol. 38, p. 16, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 17, 1925. Littorina pedroana Conrad, U. S. Pacific R. R. Repts., Vol. 5, p. 327, pi. 6, fig. 50, 1856. Lacuna solidula (Loven) Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 303, pi. 8, fig. 11, 1903. Pleistocene: Santa Barbara to San Diego (Cooper); "rare in lower San Pedro series at Deadman Island and upper San Pedro series at San Pedro," also at Pacific Beach, San Diego (Arnold); lower San Pedro at Nob Hill cut, San Pedro (T. S. Oldroyd); palisades of Santa Monica (coll. of F. C. Clark). Recent: Puget Sound, Washington, to San Diego, California; also Atlantic (Dall). Lacuna divaricata (Fabricius) variety carinata Gould Lacuna carinata Gould, Otia Conch., "Expedition Shells," p. 52, 1846; Proc. Boston Soc. Nat. Hist., Vol. 3, p. 75, 1848; U. S. Expl. Exped., Vol. 12, p. 194, 1852, Moll. Atlas, pi. 14, figs. 230, 230a, 2306, 1856; Tryon, Man. Conch., Ser. 1, Vol. 9, pi. 50, figs. 71, 72, 1887. Lacuna ? var. compacta Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 656, 1864. Lacuna (? solidula, var.) compacta Carpenter, Arm. Mag. Nat. Hist., Ser. 3, Vol. 14, p. 429, 1864. Lacuna compacta Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 302, 1903; U. S. Geol. Surv., Bull. 321, p. 74, pi. 11, fig. 2, 1907; Berry, Nautilus, Vol. 22, p. 38, 1908. Lacuna solidula var. carinata Gould, Strong, Nautilus, Vol. 38, p. 17, 1924. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 783 Pliocene: Uppermost Pliocene at Bath-house Beach, Santa Barbara (Arnold, 1907, as L. compacla Carpenter). Pleistocene: Rare in lower San Pedro series at Deadman Island; upper San Pedro series at Los Cerritos and San Pedro; Barlow's Ranch, near Ventura; Spanish Bight, San Diego (Arnold). Recent: Vancouver, British Columbia, south po-ssibly to Orange County, California (Strong). Lacuna unifasciata Carpenter Lacuna unifasciata Carpenter, Proc. Zool. Soc. London for 1856, p. 205; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 267, pi. 50, figs. 63, 74, 1887; Baker, Nautilus, Vol. 16, p. 41, 1902; Dall, U. S. Nat. Mus., Bull. 112, p. 154, 1921 ; Strong, Nautilus, Vol. 38, p. 17, 1924; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 251, 1929. Pleistocene: "Saugus" formation near Ventura (Waterfall); palisades north of Santa Monica, Los Angeles County (coll. of F. C. Clark) ; foot of Twenty-sixth Street, San Diego (F. Stephens) ; upper Pleisto- cene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to Magdalena Bay, Lower California, Mexico (Dall). Lacuna unifasciata Carpenter variety aurantiaca Carpenter Lacuna unifasciata Carpenter, var. aurantiaca Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 656, 1864; Dall, U. S. Nat. Mus., Bull. 112, p. 154, 1921; Strong, Nautilus, Vol. 38, p. 17, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art.. 22, p. 17, 1925. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, "not rare" (T. S. Oldroyd). Recent: Santa Barbara, California, to Point Abreojos, Lower California, Mexico (Dall). Lacuna porrecta Carpenter Lacuna porrecta Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 656, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 14, p. 429, 1864; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 265, pi. 50, figs. 55, 56, 57, 1887; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 303, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 154, 1921; Strong, Nautilus, Vol. 38, p. 17, 1924. Pleistocene: Lower San Pedro series at Deadman Island and San Pedro; upper series at Deadman Island, San Pedro, Los Cerritos, and Crawfish George's (Arnold); all Los Angeles County. Recent: Commander Islands, Bering Sea, southward and eastward to San Diego, California (Dall). Family FOSSARIDAE Genus ISELICA Dall, 1918 Isapis H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 320, pi. 33, fig. 8, February, 1854, not Isapis Westwood, 1851. Iselica Dall, Proc. Biol. Soc. Washington, Vol. 31, p. 137, 1918, new name for Isapis H. and A. Adams, 1854, not Westwood, 1851. Type (by monotypy), Isapis anomala C. B. Adams, figured by H. and A. Adams, op. cit., pi. 33, fig. 8, 1854. Iselica fenestrata (Carpenter) Isapis fenestrata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 628, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 14, p. 429, December, 1864. Fossarus (Isapis) fenestrata Carpenter, Arnold, Mem. Calif. .\cad. Sci., Vol. 3, p. 304, 1903. Iselica fenestrata Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 155, pi. 13, fig. 2, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 17, 1925. Pleistocene: Lower San Pedro series of Deadman Island, San Pedro (Arnold), and Nob Hill cut (Oldroyd); upper San Pedro series at Crawfish George's, San Pedro, and Deadman Island (Arnold); all in Los Angeles County. Recent: Puget Sound, British Columbia, to Gulf of California, Mexico (Dall). 784 San Diego Society of Natural History [Memoirs Family LITIOPIDAE Genus ALABA H. and A. Adams, 1853 Alaba H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 241, 1853; Nevill, Hand List Moll. Indian Mus., Pt. 2, p. 181, 1885; Woodring, Carnegie Inst., Publ. No. 385, p. 340, 1928. Type (by subsequent designation, Nevill, 1885, fide Woodring), Alaba melanura (C. B. Adams). Alaba jeannettae Bartsch Alaba jeannettse Bartsch, Proc. U. S. Nat. Mus., Vol. 39, p. 155, text figs. 3, 4, 1910. Alaba jea7ieUe Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 155, 1921; Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Type locality: Margarita Bay, Lower California, Mexico, Recent. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to Gulf of California (Dall). Alaba catalinensis Bartsch Alaba catalinensis Bartsch, Journ. Wash. Acad. Sci., Vol. 10, p. 572, 1920; Dall, U. S. Nat. Mus., Bull. 112, p. 1.56, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Catalina Island, California. Family ? Genus DIALA A. Adams, 1861 Diala acuta Carpenter Diala acuta Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 657, 1864; Dall, U. S. Nat. Mus., Bull. 112, p. 156, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 17, 1925. Pleistocene: Lower San Pedro series at Nob Hill cut, San Pedro, Los Angeles County (Oldroyd). Recent: Monterey, California, to Coronado Islands, Lower California, Mexico (DaU). For a figure of this species Dall (1921) refers questionably to Tryon's figure of Litiopa leithi Smith (Man. Conch., Ser. 1, Vol. 9, pi. 53, fig. 86, 1887). Diala marmorea Carpenter Diala marmorea Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 657, 1864; Baker, Nautilus, Vol. 16, p. 41, 1902; Berry, Vol. 22, p. 38, 1908; Dall, U. S. Nat. Mus., Bull. 112, p. 1.56, 1921. Litiopa (Diala) marmorea Carpenter, Tryon, Man. Conch., Ser. 1, Vol. 9, p. 283, pi. 53, fig. 87, 1887. Pliocene: Uppermost Pliocene at Bath-house Beach, Santa Barbara (Berry). Recent: Queen Charlotte Islands, British Columbia, to San Martin Island, Lower California, Mexico (Baker). This and the preceding species may belong to Barleeia Clark. Genus BARLEEIA Clark, 1855 Barleeia Clark, Brit. Marine Test. Moll., pp. 392-395, 1855; Bartsch, Proc. U. S. Nat. Mus., Vol. 58, p. 166, 1920. Type {fide Bartsch), Barleeia rubra (Montagu). Barleeia bentle3d Bartsch Barleeia benlleyi Bartsch, Proc. U. S. Nat. Mus., Vol. 58, p. 168, pi. 13, fig. 2, 1920; DaU, U. S. Nat. Mus., Bull. 112, p. 156, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: LIpper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Venice, California (Bartsch). Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 785 Barleeia dalli Bartsch Barleeia dalli Bartsch, Proc. U. S. Nat. Mus., Vol. 58, p. 168, pi. 13, fig. 10, 1920; DaU, U. S. Nat. Mus., Bull. 112, p. 156, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Off Point Loma, California, in 71 to 75 fathoms on sand and mud bottom (Bartsch). This and the preceding species differ from the other west American forms in having the periphery of the last whorl acutely carinated. Family ARCHITECTONICIDAE Genus ARCHITECTONICA Bolten, 1798 Architedonica Bolten, Mus. Boltenianum, p. 78, 1798; Woodring, Carnegie Inst., Publ. No. 385, p. 354, 1928. Solarium Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 74, 1799, only species, Trochus perspectii'us Linnaeus; Sowerby, Gen. Rec. Foss. Shells, pi. 202 and text, 1820-25; Tryon, Struct. Syst. Conch., Pt. 2, p. 217, 1883; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 323, 1892. Architectoma Gray, Proc. Zool. Soc. London, Pt. 15, p. 151, 1847, err. pro Architectonica Bolten. Type (by subsequent designation, Gray, 1847), Trochus perspectivus Linnaeus, Indo- Pacific, Recent. Shell low, conical, with several regularly enlargmg, tightly coiled whorls, ba.sal margin of shell subangular; aperture subtrapezoidal, outer hp simple; umbihcus open, often wide, with margins crenulated; operculum homy, subspiral. Torinia Gray has a calcareous operculum. Climacopoma Fischer' appears to have the peculiar spiral calcareous operculum of Torinia but the shell of Architectunica, sensu strido. Spirolaxis Monterosato- is a distinct genus of partly uncoiled shells with an anastrophic nucleus. Pseudomalaxis Fischer^ is dorsally flat and deeply concave ven- trally. The following species is a tjrpical Architectonica. Architectonica nobilis Bolten Architectonica nobilis Bolten, Mus. Boltenianum, p. 78, 1798; Woodring, Carnegie Inst., Publ. No. 385, p. 355, 1928. Solanum granidatum Lamarck, Hist. Anim. s. Vert., Vol. 7, p. 3, 1822; Desh. and M. Edw. Ed., Vol. 9, p. 98, 1843; Carpenter, Proc. Zool. Soc. London for 1863, p. 355, 1863; Brit. Assn. Adv. Sci., Rept. for 1863, pp. 529, 538, 541, 550, 572, 624, 667, 1864; reprinted in Smithsonian Misc. Coll., No. 252, 1872; Reeve, Conch. Icon. , Vol. 15, Solarium, pi. 2, fig. 7, 1864; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 11, pi. 5, figs. 53, 54, 1887; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 329 in part, 1892; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 58, 1895. Solarium quadriceps Hinds, Proc. Zool. Soc. London for 1844, p. 23, 1844; Carpenter, Proc. Zool. Soc. Loudon for 1863, p. 355, 1863; Brit. Assn. Adv. Sci., Rept. for 1863, pp. 529, 541, 572, 624, 667, 1864; Reeve, Conch. Icon., Vol. 15, Solarium, pi. 3, figs. 18(j, 186, 1864; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 10, pi. 4, figs. 139, 40, 1887; MabiUe, BuU. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 58, 1895. Recent: Lower California, Mexico, to Panama; also from Cape Hatteras to the Gulf of Mexico and the West Indies. Architectonica nobilis Bolten appears to be an earlier name for Solarium granulatum Lamarck. Unfortunately Lamarck did not state the habitat^ of his species and Hinds (1844), for some unknown reason, assumed that granulata was an Asiatic shell and re- described what is almost certainly the Pacific granulata as quadriceps, giving the type 1 Man. Conchyl., p. 714, 1885, monotype, Solarium patulum Lamarck. Dall'B Patulaxis may be a synonym. * Proc. Malac. Soc. London, Vol. 10, p. 363, 1913, monotype, Pseudomalaxis centrifuga Monterosato, Mediterranean Sea, Recent. 3 Man. Conchyl., p. 714, 1885, monotype, Bifrontia f zandea Philippi, Sicilian Pliocene. See discussions by Iredale, Proc. Malac. Soc. London, Vol. 9, pp. 253-257, 1911, and by Woodring, Carnegie Inst., Publ. No. 385, p. 359, 1928. * Dall (1892) and Woodring (1928) have considered granulata Lamarck, a syuonym of nobilis Bolten, a Gulf of Mexico species. Lacking evidence to the contrary, it seems more probable that Lamarck's specimen came from the Atlantic than from the Pacific, for in Lamarck's time the Atlantic was better known conchologically, Lamarck's description fits the shell commonly known as granulatum. 786 San Diego Society of Natural History [ Memoirs locality as "Bay of Panama, in five fathoms, among mud." Carpenter, who was an experienced and skillful conchologist, as well as an early student of Pacific coast mollusca, believed that the Pacific shell which Hinds named quadriceps was not distinguishable from the Gulf of Mexico grarndaia. In 1863 he stated: "I know of no mark by which to distinguish the shells of the two oceans. From each locality they vary greatly in the size of the umbilicus, and in the strength of sculpture, number of knobs, etc. I should consider them all as varieties of *S. granulatum Lam. iS. quadriceps Hds., appears dis- tinct, though it may only be an extreme variety." In his report published a year later (1864) he remarked: "On comparing suites of S. granulosum [sic] from the Texan coast with series from the Gulf of California, it appeared that on each side of the Peninsula the shells went through similar changes in strength of sculpture, size of umbilicus, number of spiral granules, etc.; nor could any clue be obtained by which the coasts could be separated in a mixed collection. Hinds's shell stands the furthest extreme of removal from S. granulatum" (p. 529). The present authors have had but a very small series of shells from the two oceans to compare; but with these few, considering Hinds' assumption of the Asiatic habitat of granuJata erroneous, and relying on Carpenter's published remarks, they believe that the Pacific shells, from the northern part of the range at least, are not even varietally distinct from the typical Texan specimens of granulata {= A. nobilis Bolten), and that Hinds' quadriceps of Panama is either a close synonym or a very unimportant southern variety or geographic race. Architectonica nobilis Bolten variety discus, new variety Plate 32, Figure 27 "Solarium quadriceps Hinds," Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 442, 1926. "Architectonica granulata Sowerby," Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Shell like that of the typical variety but with a sharper basal periphery. Dimensions : Altitude from apex to rim of umbilicus opposite aperture, 7.5 mm.; altitude from apex to lower edge of aper- ture, 11.1 mm.; diameter, 20.5 mm. Type specimen: No. 308, in the collection of the San Diego Society of Natural History. Type locality: About one mile southwest of Yuha drill hole, south of Dixieland, Imperial County. Pliocene: At the type locality (coll. by F. I. Shepherd); Coyote Mt., Imperial County (Hanna); abundant in beds east of foot of Coyote Mountain (coll. by E. H. Quayle and U. S. G.); Santa Antonita Point, Gulf of California, Mexico (Hanna and Hertlein). W. p. Woodring has recently expressed the opinion that the Coyote Mountain deposits are of lower Miocene age. It is difficult to estimate the age of these beds because so little is known of other Lower California or more southern, Pacific, fossil faunas, and even the Recent fauna is imperfectly described. The present writers would therefore await more investigation of other localities before reaching a conclusion. As most of the Coyote Mountain fossils have already been listed as Pliocene, it is thought best to give this occurrence as Pliocene also. The variety discus differs surprisingly little from the Recent form. Another variety, compressa Wiedey', from the Temblor, middle 1 Trans. San Diego Soc. Nat. Hist., Vol. 5. p. 109, pi. 9. figs. 1, 2, 1928. Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 787 Miocene, of Orange County, California, is also very similar. However, it does not have so sharp a basal margin and appears flatter. The type of compressa is rather small (greatest diameter 16 mm., height 7 mm.) and may be an immature individual. Its apparent flatness may be due partly to its immaturity. In the Recent fauna of Lower California, Mexico, there is a very small, flattened species of Architectonica with two of the spiral cords at the peripheral margin of the base. There is also a minute species in the Pliocene of the San Diego well (U. S. National Museum collection) . Family TRUNCATELLIDAE Genus TRUNCATELLA Risso, 1826 Shell smaU, subcylindrical, loosely coiled, apex obtuse or truncated when adult; aperture oval, entire, peristome continuous; operculum horny. The young shells of this genus have slender elevated spires which break or wear off before they become fully mature. The California species have definite axial riblets. Truncatella califomica Pfeiffer Truncatella californica Pfeiffer, Proc. Zool. Soc. London for 1857, p. Ill; Binney, Terrest. Air-Breathing Moll. U. S., Vol. 4, p. 28, pi. 79, figs. 20, 22, 1859; Baker, Nautilus, Vol. 16, p. 41, 1902; Dall, U. S. Nat. Mus., Bull. 112, p. 160, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro (T. S. Oldroyd); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Barbara, California, to San Martin Island, Lower California, Mexico. Truncatella stimpsoni Stearns Truncatella stimpsani Stearns, Proc. Calif. Acad. Sci., Vol. 4, p. 248, pi. 1, fig. 5, 1872; Dall, U. S. Nat. Mus., Bull. 112, p. 161, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Catalina Island, California, to Magdalena Bay, Lower California, Mexico (DaU). This species is similar to T. californica but averages larger and lighter colored. It lives among rocks at low tide line. Family SYNCERATIDAE Genus SYNCERA Gray, 1821 Syncera Gray, Med. Repos. London, Vol. 15, p. 239, 1821; Gray, Proc. Zool. Soc. London for 1847, p. 150, 1847; Bartsch, Proc. U. S. Nat. Mus., Vol. 58, p. 163, 1920. Assiminea W. E. Leach, in Fleming, Hist. Brit. Anim., p. 275, 1828. Type {fide Gray, 1847), "A. grayiana Leach" = S. hepatica Gray. Syncera translucens (Carpenter) Jeffreysia translucens Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 657, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 219, 1866. Hydrobia californica Tryon, Amer. Journ. Conch., Vol. 1, p. 221, pi. 22, fig. 11, 1865. Syncera Iransbicens Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 58, p. 164, pi. 12, fig. 7, 1920; DaU, U. S. Nat. Mus., Bull. 112, p. 161, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925; E. K. Jor- dan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Vancouver Island, British Columbia, to Lower California, Me.xico (Dall, 1921). 788 San Diego Society of Natural History [Memoirs Family CAPULIDAE Genus CAPULUS Montfort, 1810 The species of this genus have simple, somewhat irregular, cap-shaped shells. It is probably only a question of time before C. californicus Dall' or some related species is found fossil, at least in the Pleistocene; but at present the fossil record on the Pacific coast of North America is lacking. C. californicus is illustrated on plate 32, figure 33, for comparison with the shells of other simple cup or cap-shaped forms. Family HIPPONICIDAE Genus HEPPONIX Defrance, 1819 Amalthea Schumacher, Ess. Nouv. Syst. Habit. Vers Test., p. 181, 1817, not Amalthea Rafinesque, 1815. Hipponix Defrance, Journ. Phys. Chim. Hist. Nat. Arts, Vol. 88, p. 217, 1819; Gray, Proc. Zool. Soc. London for 1847, p. 157, 1847; Dall, Bull. Mus. Comp. Zool., Harvard CoUege, Vol. 46, p. 330, 1908; Woodring, Carnegie Inst., Publ. No. 385, p. 373, 1928. Type (by subsequent designation. Gray, 1847), Patella cornucopia Lamarck, Paris Basin Eocene. Amalthea Schumacher has often been used for Hipponix but appears to be a homo- nym of Amalthea Rafinesque- (Analy. Nat., p. 123, 1815, ^de Woodring). Hipponix antiquatus (Linnseus) Paldla aniiquata Linnseus, Syst. Nat., Ed. 12, p. 1259, 1767. Hipponix antiquatus Linnaeus, Tryon, Man. Conch,, Ser. 1, Vol. 8, p. 134, pi. 40, figs. 93-99, 1886; Cooper, 7th Ann. Kept. Calif. Stat« Mineralogist, p. 244, 1888; Keep, West Coast Shells, p. 74, fig. 59, 1888, 1892; .Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 312, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 161, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. Pliocene: Santa Antonita Point, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: "Pliocene" of Deadman Island ( = Timms Point zone] and lower San Pedro series of Deadman Island (.\rnold) and San Pedro (T. S. Oldroyd); palisades north of Santa Monica, Los .Angeles County (collection of F. C. Clark). Recent: Crescent City, California, to Panama and Galapagos Islands (Dall, 1921). Hipponix antiquatus (Linnseus) variety cranioides Carpenter Hipponix cranioides Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 428, 1864; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 135, pi. 40, fig. 6, 1886; Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 244, 188S; .Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 312, 1903. Hipponix antiqiiaius cranioides Carpenter, Dall, V. S. Nat. Mus., Bull. 112, p. 161, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. IS, 1925. Pleistocene: Santa Barbara (Cooper); lower San Pedro series at Nob Hill cut (Oldroyd), San Pedro, and Deadman Island; upper San Pedro series at Deadman Island and Los Cerritos, also at Spanish Bight, San Diego (Arnold). Recent: Vancouver Island, British Columbia, to San Pedro, California (DaU, 1921). Hipponix tumens Carpenter Hipponix tumens Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 654, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 180, 1865; Tryon, Man. Conch., Ser. 1, Vol. 8, pi. 40, fig. 7, 1886; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 313, 1903; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; DaU, U. S. Nat. Mus., Bull. 112, p. 161, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. » Described in the Nautilus, Vol. 13, p. 100, 1900, and illustrated in Bull. 112, U. S. Nat. Mus., p. 161, pi. 15, fig. 6, 1921; living from San Pedro to San Diego on Pectens. * Sherborn, Index. Anim., gives Amalthea Rafinesque as a nomen nudum. The original reference has not been available to the present authors. Volume I] PLIOCENE AND PLEISTOCENE MOLLITSCA OF CALIFORNIA 789 Pleistocene: Santa Monica (collection of F. C. Clark) ; lower San Pedro series of Nob Hill cut at San Pedro (Oldroyd) and Deadman Island (Arnold); lower Quaternary at Magdalena Bay, Lower Calif ornia, Mexico (Jordan); chiton bed at Point Firmin, Los Angeles County (Chace); upper Pleistocene at Pacific Beach, San Diego (Arnold); San Quintin Bay, Lower California, Mexico (Jordan). Recent: Crescent City to San Diego, California (Dall, 1921). The name Hipponix has frequently been spelled with a "y-" This being a pure misspelling, the errors have not been segregated in the foregoing synonymy. In the Stanford University collections there are specimens labeled Hipponix bar- batus Lamarck, collected by R. H. Palmer in the Pleistocene beds of Oaxaca, Mexico. Family CREPIDULIDAE Genus CREPIDULA Lamarck, 1799 Crepidvla Lamarck, Mem. Soc. Hist. Nat. Paris, Ser. 1, Vol. 1, p. 78, 1799; Dall, Bull. Mus. Comp. Zool. Harvard College, Vol. 9, p. 79, 1881; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 123, 1886; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 354, 1892. Type (by monotypy), Patella fornicata Linnaeus, figured by Tryon, op. cit., p. 124, pi. 36, figs. 1-8, 1886, Atlantic and Gulf coasts of North America, Recent. Shell oval, Hmpet-like, with a large body whorl and large aperture, and a small, closely appressed spire of few whorls; interior with a shelly lamina, or shelf, covering the posterior part of the body cavity. Geologic range: Cretaceous to Recent. Section Crepidula, s. s. Crepidula princeps Conrad Crepidula pri7iceps Conrad, U. S. Pacific R. R. Repts., Vol. 5, p. 326, pi. 6, figs. 52, 52a, 1856; Dall, in Spurr, U. S. Geol. Surv., Twentieth Ann. Rept., Pt. 7, p. 264, 1900; Arnold, Smithsonian Misc. CoU., Vol. 50, pp. 422, 424, 1907; Eldridge and Arnold, U. S. Geol. Surv., BuU. 309, pp. 26, 153, 1907; Arnold, Bull. 322, p. 58, pi. 24, figs. 1, 2, 1907; Proc. U. S. Nat. Mus., Vol. 34, pp. 350, 353, 354, 355, 1908; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 84, pi. 8, pi. 9, fig. 5, pi. 10, fig. 2, 1909; Arnold, Bull. 396, U. S. Geol. Surv., pp. 25, 26, 31, 35, 39, 152, pi. 23, fig. 2, 1910; Arnold and R. ,\nderson. Bull. 398, pp. 110, 126, 129, 132, 324, pi. 45, fig. 2, 1910; F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 100, 1911; W. F. Jones, Univ. Calif. Publ. Geol., Vol. 6, pp. 68, 71, 1911; J. P. Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 175, 1912; Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 43, 1914; English, Univ. Calif. Publ. Geol., Vol. 8, pp. 210, 213, 1914; Clark, p. 422, 1915; Nomland, Vol. 9, p. 206, 1916; Martin, pp. 229, 231, 243, 245, 256, 1916; Moody, Vol. 10, pp. 43, 46, 1916; Weaver, Proc. Calif. Acad. Sci., Ser. 4, Vol. 6, p. 38, 1916; Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 212, 221, 301, 1917; J. P. Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 9, pp. 136, 137, 144, 146, 151, 156, 160, 1919; Dickerson, Vol. 9, p. 550, 1922; Kew, U. S. Geol. Surv., BuU. 753, p. 78, 1924; WaterfaU, Univ. Calif. Publ. Geol., Vol. 18, pp. 77, 78, 79, 1929. "Crepidula grandis Middendorff," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 534, 539, 590, 1864; Watts, Calif. State Mining Bureau, Bull. 3, pp. 40, 54, etc., 1894; Ashley, Proc. Calif. Acad. Sci., Ser. 2, Vol. 5, pp. 318, 320, etc., 1895; Watts, Calif. St. Mining Bureau, Bull. 11, p. 79, 1897; Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 309, 310, 1903; Haehl and Arnold, Proc. .^imer. Philos. Soc, Vol. 43, pp. 20, 24, 1904; not of Middendorff, 1849, nor of Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 216, 1857; Rept. for 1863, p. 584, 1864, nor of DaD, U. S. Nat. Mus., Bull. 112, p. 162, 1921, nor of I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 116, 1927. "Crypta grandis Middendorff," Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 82, 1868; Cooper, 7th Ami. Rept. Calif. State Mineralogist, p. 265, 1888, in part; Watts, Calif. State Mining Bureau, Bull. 3, p. 54, 1894, in part, not of Middendorff, 1849. Shell large, thick, heavy, elongate, beak sharply twisted to the side and m most cases appressed to the body whorl but occasionally twisted somewhat outward, apex usually turned up away from the aperture; body whorl ventricose, with axis of greatest curvature well to the side (right) of the median line; sculpture of growth lines but no spiral or radial sculpture; aperture ovate or elliptical. 790 San Diego Society of Natural History [Memoirs lip simple or sometimes tliickened at the apical edge, iiaternal shelly septum extending over half of the aperture, concave, with a gentle curve at its juncture with the shell. Size: 93 mm. in length; 50 mm. in width; 41 mm. in height perpendicular to the plane of the aperture. Miocene: Cape Yaktag, Alaska (Dall, in Spurr, 1900); lower Miocene of western Washington (Weaver); lower Miocene of La Panza quadrangle, San Luis Obispo County; of Searsville Road, 3 miles southwest of Stanford University campus, Santa Clara County (.\rnold; Dall, 1909); upper Miocene of western Washington (Weaver) ; Empire formation of Oregon (Dall, 1909) ; Arnold and Hannibal, 1913); San Pablo formation of middle California (Merriam; Clark, 1915); etc. Pliocene: Purisima formation, S. D. S. N. H. loc. 104, beach south of Purisima Creek (Grant and Gale); lower Merced of Seven Mile Beach, San Mateo County (Ashley; Martin); Merced of Ano Neuvo Bay, San Mateo County, and Etchegoin of Sargent oil field, San Benito County (Martin) ; Etchegoin of Coalinga region (Nomland) ; Fernando of Santa Maria district, Santa Barbara County (Arnold); San Diego formation of Pacific Beach, S. D. S. N. H. loc. 100 (U. S. G.); middle Pliocene of Holser Canyon, Los Angeles County (H. R. G.); middle or upper Pliocene of the west branch of O'Hare Canyon, Ventura County (H. R. G.); upper Pliocene between Timber Canyon and Santa Paula Creek, and of Sulphur Canyon east of South Mountain, Ventura County (H. R. G.); etc. Pleistocene: Lower Pleistocene of Adams Canyon; between Hampton and Aliso canyons; between .\dams and O'Hare canyons, etc., Ventura County (U. S. G.); upper San Pedro formation of Deadnian Island, Los Angeles County (.\rnold, 1903, as C. grandis); etc. This is a large, heavy species, which, though extinct, is represented by a direct descendent, C. grandis Middendorff, in the Recent boreal fauna. The Recent species is in most cases thinner shelled, less convex, and relatively broader than the fossil ances- tor. Some of the Pleistocene specimens of C. princeps show a broadening and flattening which appears to be a step toward C. grandis. Waterfall has recently described a Crepidula from the Pleistocene beds near Ventura as Crepidula saugusensis.^ It appears to be an onyx or a young princeps, perhaps like the Pliocene specimens from localities 221 and 222 referred below to onyx. All the species of this genus are variable, and it is hkely that many fossil records are based upon mis- identifications. It may be possible to distinguish the young of C. princeps from C. onyx by the character of the deck or shelly diaphragm. C. princeps generally has one broad curved indentation of the deck margin while C. onyx has two of unequal size. Crepidula onyx Sowerby Plate 32, Figure 34 Crepidula onyx Sowerby, Gen. Shells, No. 23, fig. 2, 1824; Carpenter, Proc. Zool. Soc. London for 1856, p. 225; Brit. Assn. Adv. Soi., Rept. for 1856, p. 323, 1857; Reeve, Conch. Icon., Vol. 11, Crepidula, pi. 2, figs. 9a, 9b, 1859; Tryon, Man. Conch., Ser. 1 , Vol. 8, pi. 37, fig. 37, pi. 38, figs. 43-50, pi. 39, fig. 59, 1886; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 310, 1903; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 174, pi. 23, figs. 2, 5, 1909; J. P. Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 175, 1912; Arnold and Hannibal, Proc. .4mer, Philos. Soc, Vol. 52, p. 593, 1913; English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Clark, Vol. 8, pp. 405, 422, 1915; Nom- land, Vol. 9, p. 82, 1916; Martin, Vol. 9, pp. 229, 256, 1916; Dall, U. S. Nat. Mus., Bull. 112, p. 162, 1921; Dickerson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, p. 564, 1922; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 92 and table opposite, 1922; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 448, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 117, 1927. Crepidula r^igosa Nuttall, MS., Carpenter, Proc. Zool. Soc. London for 1856, p. 224; Brit. Assn. Adv. Sci., Rept. for 1863, p. 654, 1864; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 12S, pi. 37, fig. 37, 1886. Crepidula onyx Sby., var. rugosa Nuttall, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 203, 1893. > Univ. Calif. Publ. Geol., Vol. 18, p. 87, pi. 6, fig. 7, 1929. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 791 Miocene: Empire formation of Coos Bay, Oregon (Howe); upper and lower San Pablo and Santa Margarita formations (Clark, 1915). Pliocene: Coyote Mountain, Imperial County (Hanna); Jacalitos and Etchegoin formations (Clark, 1915); middle Pliocene of localities 221 and 222, Ventura County, common (H. R. G.); two specimens irregularly striated as in rugosa from locality 2176, Holser Canyon, Los Angeles County (H. R. G.). Pleistocene: Lower San Pedro series at San Pedro and Deadman Island (Arnold) and Nob Hill cut (T. "S. Oldroyd); lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan); upper San Pedro series at Deadman Island, San Pedro, and Los Cerritos, Los .\ngeles County, and Pacific Beach and Spanish Bight, San Diego (^Irnold); Santa Monica, Los Angeles County (Oldroyd Collection at Stanford University). Recent: Monterey, California, to Panama (Dall, 1921). This species is much smaller than C. pi-inceps. It is much like C. fornicata of the Atlantic coast, and it is entirely possible that the Ventura County Pliocene specimens noted above, even that onyx as a whole, should be identified as fornicata or a variety oi fornicata. Crepidula adunca Sowerby Crepidula adunca Sowerby, Cat. Tankerville, Appen., p. 7, 1825; Reeve, Conch. Icon., Vol. 11, Crepidula, pi. 2, fig. 12, 1859; Gabb, Geol. Surv. Calif., Palao., Vol. 2, p. 82, 1868-9; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 129, pi. 38, figs. 51-55, pi. 37, figs. 39, 40, pi. 39, fig. 60, 1886; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 236, 1888; Dall, Trans. Wagner Inst. Sci., Vol. 3, pp. 355, 358, 1892; Pilsbry and Vanatta, Proc. Wash. Acad. Sci., Vol. 4, p. 552, 1902; Arnold, Mem. Calif. Acad. Sci., Vol. 3, pp. 55, 308, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908; Arnold and Hannibal, Proc. .Ajner. Philos. Soc, Vol. 52, p. 590, 1913; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 422, 1915; Nomland, Vol. 9, p. 203, 1916; Moody, Vol. 10, p. 43, 1916; Nomland, Vol. 10, pp. 212, 221, 1917; DaU, U. S. Nat. Mus., Bull. 112, p. 162, 1921; I. S. Oldroyd, Univ. Wash. Publ. Puget Sound Biol. Sta., Vol. 4, p. 158, pi. 11, fig. 6, 1924; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Crepidula rosiriformis Gould, Proc. Boston Soc. Nat. Hist., Vol. 2, p. 160, 1846; U. S. Expl. Exped., Vol. 12, p. 375, 1852, Atlas Moll., fig. 482, 1856. Miocene: Empire formation of Coos Bay, Oregon (Howe); upper San Pablo formation of middle CaUfomia (Clark). Pliocene: Etchegoin formation of Coalinga region (Nomland); Fourth and Broadway, Los Angeles (Moody); Bath-house Beach, Santa Barbara (Berry). Pleistocene: Lower San Pedro series of Deadman Island and San Pedro (Arnold) and of Nob Hill cut at San Pedro (T. S. Oldroyd); Barlow's Ranch, near Ventura (Arnold); "Saugus" formation near Ventura (Waterfall); upper San Pedro series in San Pedro region (Arnold) and at Santa Monica (coU. of F. C. Clark); Spanish Bight, San Diego (Arnold); etc. Recent: Vancouver Island, British Columbia, to Cape San Lucas, Lower California, Mexico (DaU, 1921). This is an oval, nearly round shell with the beak hardly twisted and usually elevated above the plane of the aperture. It is likely that the Miocene records should be assigned to C. proerupta Conrad or some other species. Crepidula aculeata (Gmelin) Patella aculeata Gmelin, Syst. Nat., Ed. 13, p. 3320, 1790. Crepidula aculeata Gmelin, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 129, pi. 39, figs. 61-65, 1886; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 236, 1888; .\rnold, Mem. Calif. Acad. Sci., Vol. 3, p. 308, 1903; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; Dall, U. S. Nat. Mus., BuU. 112, p. 162, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. IS, 1925. Pliocene: San Fernando, Los Angeles County (Cooper); Florida (DaU, ^de Arnold). Pleistocene: "Rare in lower San Pedro series of San Pedro and Deadman Island" (Arnold); Nob Hill cut, San Pedro (T. S . Oldroyd) ; Point Firmin chiton bed (Chace) ; aU in Los Angeles County. Recent: Santa Barbara, California, to Valparaiso, ChUe (DaU, 1921); ? also Atlantic. Crepidula aculeata can be recognized by its crenulated radial sculpture. Calyptrcea echinus Broderip and Calyptroea hystrix Broderip may be synonyms. 792 San Diego Society of Natural History [Memoirs Crepidula excavata (Broderip) Calyptrsea excavata Broderip, Proc. Zool. Soc. London for 1834, p. 46, 1834; Trans. Zool. Soc. London, Vol. 1, p. 205, pi. 29, fig. 7, 1835. Crepidula excavata Broderip, Dall, Nautilus, Vol. 32, p. 24, 1918; U. S. Nat. Mus., Bull. 112, p. 162, 1921; T. S. Old- royd, Proe. U. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro (T. S. Oldroyd); Magdalena Bay (Dall, 1918), and upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan); Santa Monica palisades, Los Angeles County (Oldroyd Collection at Stanford LIniversity). Recent: Monterey, California, to Payta, Peru (Dall, 1921). Section Crepipatella Lesson, 1830 Crepidula lingulata Gould Crepidula lingulata Gould, Proc. Boston Soc. Nat. Hi.st., Vol. 2, p. 160, 1846; U. S. Expl. Exped., Vol. 12, p. 376, 1852, Atlas Moll., figs. 481, 481o-f, 1856; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. "Crepidula dorsata Broderip," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 654, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 236, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 309, 1903, not Crepidula dorsata Broderip, 1834. Crepidula {Crepipatella) lingulata Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 162, 1921. Pliocene: San Fernando, Los Angeles County (Cooper); ? Santa Barbara (Cooper, as Pleistocene). Pleistocene: Rare in lower San Pedro series of Deadman Island, Los Angeles County (Arnold) ; lower Quater- nary at Magdalena Bay, Lower California (Jordan, 1924, identification by Dall) ; upper San Pedro series of Crawfish George's and Los Cerritos, Los Angeles County (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Bering Sea to Panama (Dall). This flattish, crudely radially sculptured species can be recognized by its distinctive deck which protrudes into the body cavity separated from the shell for some distance on one side. The margin of the deck has one small V-shaped indentation due to a low radial fold which probably compensates structurally for the lack of complete lateral attachment to the shell. Section Ianacus Morch, 1852 Crepidula nummaria Gould Crepidula navicelloides Nuttall, in Jay's Cat. Shells, Ed. 3, p. 41, 1839, nomen nudum; Carpenter, Brit. Assn. Ady. Sci., Rept. for 1863, p. 654, 1864; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 82, 1868-9; Dall, Proc. Calif. Acad. Sci., Vol. 5, p. 297, 1874; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 237, 1888; Keep, West Coast Shells, p. 76, fig. 61, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 310, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908. Crepidula nummaria Gould, Proc. Boston Soc. Nat. Hist., Vol. 2, p. 160, 1846; U. S. E.xpl. Exped., Vol. 12, p. 377, 1852, Atlas Moll., figs. 480, 480a-6, 1856; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Crepidula (Ianacus) nummaria Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 163, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art,. 22, p. 18, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 120, pi. 91, figs. 14, 14a-6, 1927. Type locality: Classet, Puget Sound, Recent. Pliocene: San Diego well, Balboa Park, San Diego (Dall, as C. navicdloides Nuttall) ; Bath-house Beach, Santa Barbara (Arnold; Berry; as navicelloides). Pleistocene: Lower San Pedro series of Deadman Island, "rare" (Arnold); lower San Pedro series of Nob Hill cut at Second and Pacific Streets, San Pedro, "plentiful" (Oldroyd, 1925); upper San Pedro series of Crawfish George's, Los Cerritos, San Pedro, and Deadman Island, Los Angeles County (Arnold ) . Recent: Plover Bay, Bering Strait, to Mazatlan, Mexico (Dall, 1921J. VoLiME 1 1 Pliocene and Pleistocene AIollusca of California 793 This is typically a round, flat, rather thin-shelled species, but it varies with its situs, sometimes being quite elongate or irregular. C. nivea C. B. Adams is probably a synonym or a variety. This species, like the other Pacific coast species, needs more careful study before specific limits can be determined. Family CALYPTRAEIDAE Genus CRUCIBULtJM Schumacher, 1817 Crvcibvhtm Schumacher, Ess. Nouv. Syst. Habit. Vers Test., pp. 56, 182, 1S17. Section Crucibulum, s. s. Adult with entire margin of internal cup free from shell wall. Crucibulum spinosum (Sowerby) Calyptriea spinosa Sowerby, Gen. Shells, pi. 23, figs. 4, 7, 1824. Crucibulum spinosum Sowerby, Conrad, U. S. Pac. R. R. Repts., Vol. 5, p. 327, pi. 5, fig. 46, 1856; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 323, pi. 9, figs. 3a-3p (explanation of plate on p. 3), 1857; Reeve, Conch. Icon., Vol. 11, Crucibulum, pi. 4, figs. \Oa-k, 1859; Carpenter, Brit. Assn. .4dv. Sci., Rept. for 1863, p. 654, 1864; Tryon, Man. Conch., Ser. 1, Vol. 8, pi. 32, fig. 38, 1886; Cooper, 7th .^n. Rept. Calif. State Mineral- ogist, p. 237, 1888; Keep, West Coast SheUs, p. 77, fig. 62, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 306, 1903; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 233, 1909; Nautilus, Vol. 32, p. 24, 1918; U. S. Nat. Mus., Bull. 112, p. 163, 1921; Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 448, 1926; Jordan, Proc. Calif. Acad. Sci., .Ser. 4, Vol. 15, p. 246, 1926; Hanna and Hertlein, Vol. 16, p. 142, 1927; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 251, 1929. Pliocene: Coyote Mountain, Imperial County (Hanna); San Diego well (Dall, fide Arnold); Carmen Island, Gulf of California (Hanna and Hertlein); Santa Barbara (Cooper). Pleistocene: Lower San Pedro series of Deadman Island, "common" (Arnold); lower Quaternary at Magda- lena Bay, Lower California, Mexico (Dall, 1918; Jordan, 1924); upper San Pedro series of Deadman Island, San Pedro, Los Cerritos, Long Beach, and Crawfish George's (Arnold), and of the Santa Monica palisades (collection of F. C. Clark), Los .\ngeles County; foot of Twenty-sixth Street, San Diego (Stephens) ; upper Pleistocene at San Quintin Bay (Jordan, 1926) and of coast of Oaxaca, Mexico (Palmer). Recent: Trinidad, California, to Tome, Chile, and the Galapagos Islands (Dall, 1921). Crucibulum imbricatum (Sowerby) Calyptrsea imbricala Sowerby, Gen. SheUs, No. 23, fig. 5, 1824; Broderip, Proc. Zool. Soc. London, Pt. 2, p. 36, July, 18.34. Crucibulum imbricatum "Broderip," Carpenter, Brit. .\ssn. .Adv. Sci., Rept. for 1856, p. 3, pi. 9, figs, la-g, 18.57; Reeve, Conch. Icon., Vol. 11, Crucibulum, pi. 3, figs. 8f, 8d, 9f, 9d, 1858; Mabille, Bull. Soc. Philom. Paris, Ser. 8, Vol. 7, p. 58, 1895. Crucibulum imbricatum Sowerby, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 233, 1909; Nautilus, Vol. 32, p. 24, 1918; Jordan, Bull. So. Calif. .\cad. Sci., Vol. 23, pp. 149, 152, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 142, 1927. Pliocene: Coronados Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary at Magdalena Bay (Dall; Jordan), and upper Pleistocene at Scammons Lagoon (Jordan), Lower California, Mexico. Recent: Gulf of California to Callao, Peru, and the Galapagos Islands (DaU, 1909). In the collections at Stanford University there are specimens labeled C. scuteUatum Gray, C. tenue Broderip, and C. umhrellum Deshayes, all collected by R. H. Palmer from the Pleistocene on the coast of Oaxaca, Mexico. 794 San Diego Society of Natural History [Memoirs Genus CALYPTRAEA Lamarck, 1799 Calyplrxa Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, ]). 78, 1799. Type (by monotypy), Patella chinensis Linnseus. Shell conical, with a central or subcentral apex that may be spiral; aperture basal, with an in- ternal spiral diaphragm, which has a twisted columellar border. Cheilea Modeer, 1793, is a genus of conical, cup-shaped shells with an imperfect funnel-like process within. It is generically distinct from Calyptrcea. Calyptraea mamillaris Broderip Plate 32, Figures 24a, 24b Calypirita mamillaris Broderip, Proc. Zool. Soc. London for 1834, p. 38, July, 1834; Trans. Zool. Soc. London, Vol. 1, p. 201, pi. 28, fig. 5, 1835, placed questionably in subgenus Siphopatella; Tryon, Man. Conch., Ser. 1, Vol. 8, pi. 34, figs. 64-67, 1886; Strong, Nautilus, Vol. 39, p. 9, 1925; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 341, pi. 32, fig. 10, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Calypirsea (Trochalella) mammillaris Broderip, d'Orbigny, Voy. Amer. Merid., Moll., p. 462, 1841. Calyplrsea fastigiala Gould, Proc. Boston Soc. Nat. Hist., Vol. 2, p. 161, 1846; Rept. U. S. Expl. Exped., Vol. 12, p. 379, 1852, Atlas, Moll., pi. 32, figs. 484, 484a-b, 1856; Dall, U. S. Nat. Mus., Bull. 112, p. 163, 1921; T. S. Oldroyd, Proc. V. S. Nat. Mus., Vol. 65, Art. 22, p. 18, 1925; Strong, Nautilus, Vol. 39, p. 9, 1925. Trochita inornata Gabb, Geol. Surv. Calif., Pateo., Vol. 2, pp. 51, 81, pi. 14, fig. 8a, 1868-9; Merriam, Univ. Calif. Publ. Geol., Vol. 2, p. 106, 1896; Reagan, Trans. Kansas Acad. Sci., Vol. 22, pp. 171, 195, pi. 3, fig. 31, 1909; Clark, Vol. 8, p. 421, 1915; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 243, 1916; Howe, Vol. 14, table opp. p. 93, 1922. Galerus inornatus Cooper, Bull. Calif. State Mining Bureau, No. 11, pp. 79, 82, 1896. Galerus mammillaris Broderip, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 307, 1903. Calyptrs-a (Trochita) inornala Gabb, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 82, pi. 5, figs. 6, 11, pi. 6, fig. 4, 1909. Calyplrsea inornata Gabb, Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 590, 1913. Miocene: Empire formation of Coos Bay, Oregon (Dall; Arnold and Hannibal; Howe); San Pablo formation, upper Miocene of middle California (Clark). Pliocene: Merced and Purisima formations of San Francisco region (Martin; etc.); Etchegoin formation of San Joaquin basin (Clark); San Diego well, San Diego (Dall, fide Arnold, 1903); "Pico" formation near Ventura (Waterfall); near Half Moon Bay, San Mateo County (Gabb, as Miocene); etc. Pleistocene: Upper and lower Pleistocene of San Pedro region (Arnold; T. S. Oldroyd). Recent: Alaska to South America. C. fastigiata Gould is a name given to the northern smaller individuals. The type locality of fastigiata is Puget Sound. Recent conchologists consider Calyptrcea fastigiata and C. mamillaris distinct species, basing their reasons for so doing on the difference in the ranges of the northern and the southern shells which do not overlap but are separated by over a thousand miles of coast line. The southern form (C. mamillaris) may be slightly thicker shelled and perhaps average a very little larger, but such differences are not greater than can be found between shells chosen from the extremities of the ranges of many other species. In fact the differences between these two species are very much smaller than the differences between many other species, and objectively considered they appear conspecific. C. fastigiata ranges only as far south as Puget Sound, so far as known, while C. viainillaris does not live as far north as San Diego, part of the intermediate region being occupied by C. con- torta, which is possibly a distinct species. Such an anomalous range is difficult to explain on the basis of temperature control, but it is possible that some other influence, as yet unknown, accounts for the hiatus in distribution. In this case it may be due to control by the presence of some enemy or absence of food; or the northern individuals became separated from the southern stock by diastrophic events, and having become permanently Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 795 adjusted to northern conditions they are now intolerant of other conditions. Such possibiHties are entirely speculative, however; and it seems more likely, either that contorta is the same species and there is no real hiatus, or that mamillaris and fastigiata are also distinct. Calyptraea filosa (Gabb) Trochita filosa Gabb, Geol. Surv. Calif., Palao., Vol. 2, p. 15, pi. 2, figs. 25, 25a, 1866; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 545, pi. 50, figs. 2, 2a, 1907; U. S. Geol. Surv., Bull. 309, pi. 40, figs. 2, 2a, 1907; English, Univ. Calif. Ribl. Geol., Vol. 8, p. 210, 1914; Clark, Vol. 8, p. 421, 1915; Martin, Vol. 9, p. 2.55, 1916; Nomland, Vol. 10, p. 221, 1917. Miocene: San Pablo and Santa Margarita formations of middle California (Clark). Pliocene: Common in the Jacalitos and Etchegoin formations of the Coalinga district (Nomland); Etohegoin and Merced of Sargent oil field, San Benito County, and Purisima and lower Merced of San Fran- ciscan region (Martin); lower Pliocene of Elsmere Canyon (Arnold; English). This species ranges from the upper Miocene into the middle Pliocene, so far as known. The sutures are less distinct and the radial sculpture much finer than in Calyp- trcea trochiformis (Gmelin). Subgenus TROCHITA Schumacher, 1817 Calyptraea (Trochita) trochiformis (Gmelin) Plate 31, Figure 11 Patella trochiformis Gmelin, Syst. Nat., Ed. 13, Vol. 8, p. 3693, 1790. Trochus radians Lamarck, Hist. Anim. s. Vert., Vol. 7, p. 11, 1822. Calyptrxa radians Lamarck, Hist. Anim. s. Vert., Deshayes and Milne Edwards Ed., Vol. 7, p. 626, 1836. ? Trochita costellata Conrad, U. S. Pacific R. R. Repts., Vol. 7, p. 195, pi. 7, fig. 3, 18.57; .\rnold, U. S. Geol. Surv., Bull. 309, p. 236, pi. 32, fig. 3, 1907; not Calyptrxa costellata Philippi, Arch. f. Naturg., Vol. 11, pt. 1, p. 62, 1845. Calyptrsea (Infundibulum) radians Lamarck, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 121, pi. 35, figs. 84, 85, 1886. ;' Calyptrsea costellata Conrad, Clark, Univ. Calif. Publ. Geol., Vol. 7, p. 54, 1912. ? Calyptrxa martini Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 486, pi. 70, fig. 8, 1915. Calyptrxa radians "Arnold," English, Univ. Calif. Publ. Geol., Vol. 8, p. 210, 1914; Carson, Bull. So. Calif. Acad. Sci., Vol. 25, p. 49, 1926. Miocene: Three miles south of Calabasas, Los Angeles County, in the Topanga formation (a local name for the Temblor formation, lower middle Miocene); "common in the Miocene" (Arnold, as Trochita costellata Conrad) ; upper San Pablo east of Walnut Creek, Contra Costa County, and uppermost fossiliferous beds of the Santa Margarita formation, north of Coalinga (Clark, 1915, as C. martini); etc. Pliocene: Fugler Point asphalt mine, one mile north-northwest of Gary, at head of .Santa Maria Valley (Ar- nold); "Fernando" of Holser Canyon, Los Angeles County (English); Puente HiUs, Los Angeles County (Carson). Recent: Panama to Peru. In the second edition of Lamarck's "Histoire Naturelle des Animaux sans Verte- bres," Calyptrcea radicms is stated to be conspecific with Gmelin's earlier name Patella trochiformis; hence we have used the prior name. In the California Miocene a fossil Calyptrcea occurs which is identical with the Recent species of South America. It is a large species with numerous prominent axial ribs. This Miocene fossil has been called Trochita or Calyptrcea costellata Conrad (not Calyptrcea costellata Philippi, 1845). Con- rad's type was a sandstone cast from Gaviota Pass, Santa Barbara County, probably lower Miocene but possibly upper Eocene. His figure, which is characteristically poor, shows no sign of the radiating ribs which are so conspicuous on the fossil to which his name has been applied and which are mentioned in his description. A comparison of 796 San Diego Society of Natural History [ Memoirs Conrad's type with specimens collected from Gaviota Pass would probably settle the uncertainty over Conrad's species. Clark (1912) reported Calyptrcea costellata from the lower part of the San Pablo series in the Kirker's Pass region, Contra Costa County, but in a later paper he stated his former identification was wrong and that the shell was a new species which he de- scribed as Calyptrcea diabloensis.^ In the same paper he described Calyptroea martini, which, from his figure, appears to be identical with the Recent South American shell. A careful study of a series of Miocene specimens of this clan may show that there is but one species with two or possibly three varieties in the California fossil faunas. This species is the type of the subgenus Trochita Schumacher. abutttno suture parietal callus umbilicus {unicle Text figtjbe 9. A Naticoid shell illus- trating the application of descriptive terms. — From Marwick. Family NATICIDAE Shell globular or oval, spire usually short, aperture semi- lunar, without canal or anterior notch, the outer lip sharp, the columellar lip callous, more or less reflected over the umbiU- cus. (Tryon.) Some of the terms applied to shells of this family are illustrated in the text figure taken from Marwick. Genus NATICA Scopoli, 1777 Nalica Adanson, Hist. Nat. Senegal, p. 172, 1757, pre-Linnsean. Nalica Scopoli, Introductio ad ffistoriam Naturalem, p. 392, 1777; Harris, Cat. Tert. Moll. Brit. Mus., Pt. 1, p. 255, 1897; Dall, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 332, 1908; U. S. Geol. Surv., Prof. Paper 59, p. 85, 1909; Marwick, Trans. New Zealand Inst., Vol. 55, p. 548, 1924; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 323, 1927; Woodring, Carnegie Inst., Publ. No. 385, p. 377, 1928. Type (by subsequent designation, Harris, 1897), Nerita vitellus Linnaeus, figured by Tryon, Man. Conch., Ser. 1, Vol. 8, p. 29, pi. 8, fig. 60, 1886, PhiUppines, Singapore, Recent. Subgenus NATICA, s. s. Shell globose, solid, smooth, suture well marked and generally abutting, aperture semilunar, outer lip straight, inclmed 20-30° from vertical, inner margin with moderate callus on parietal wall, generally not invading umbilicus, which is open and contains a funicle spiralling up apertural wall. (Marwick, 1924.) The typical subgenus is represented on the Pacific coast by but few species. Tec- tonatica has a smooth operculum in addition to a closed umbiHcus. Woodring (1928) questions the value of opercular characters. He points out that Dall used Natica, s. s., for the canrena group, for which Naticarius Dumeril is a more appropriate name.^ 1 Univ. Calif. Pub. Geol.. Vol. 8, p. 485, pi. 70, fig. 9, 1915. ! Zool. Analytique, p. 164, 1805. The assumption that Nalicarius is a substitute name for Natica Lamarck, 1799. not Scopoli, 1777, is probably unwarranted; but in this case it makes no difference, for Froriep. who was the first to assign species to the genus, cited in his trans- lation of Dumeril, p. 165, 1S06, the sole species Nerita cumena Linnffius, which becomes the type by monotypy of Naticarius Dumfiril as well as of Natica Lamarck. See Iredale, Proc. Malac. Soc. London, Vol. 12, p. 83, 1916. Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 797 Natica (Natica) unifasciata Lamarck Text Figure 10 Natica unifasciata Lamarck, Hist. Nat. Anim. s. Vert., Vol. 6, pt. 2, p. 201, 1822; Deshayes and Milne Edwards Ed., Vol. 8, p. 640, 1838; Reeve, Conch. Icon., Vol. 9, Natica, pi. 12, figs. 49a, 496, 1855; DaU, Proc. U. S. Nat. Mus., Vol. 37, p. 235, 1909; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 451, 1926. Natica (Natica) marochiensis Gmelin, var. unifasciata Lamarck, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 23, pi. 5, fig. 93, 1886. Pliocene: Coyote Mountain, western Imperial County (Hanna). Text FionRE 10. Natim Pleistocene: Magdalena Bay, Lower California, Mexico (Hanna). unifasciata Lamarck, Recent: Panama north to Gulf of California. ? Peru. a typical Natica. Re- cent specimen from This species is something Hke N. canrena but lacks the multiple [^\he"'oiL^oyrcoi- spiral sulcations on the exterior of the operculum. It does not belong lection at Stanford to the Section Naticarius Dumeril, if this opercular character is of si^e!^""'*^' significance. The umbilical characters are the same. Subgenus TECTONATICA Sacco, 1890 Tectonalica Sacco, Bollettino Musei Zoologia Anatomia Comparata R. Universita Torino, Vol. 5, (No. 86), p. 33, 1890; Cossmann, Ess. Paleo. Comp., Vol. 13, p. 119, pi. 2, figs. 13, 14, 1925; Woodring, Carnegie Inst., Publ. No. 385, p. 384, 1928. Cryplonaiica DaU, Trans. Wagner Inst. Sci., Vol. 3, p. 362, 1892; U. S. Geol. Surv., Prof. Paper .59, p. 85, 1909; not of Kittl, 1894. Type (by monotypy) Natica tectula Bonelli, Italian Pliocene. Shell globose; umbilicus entirely fiUed with a callus deposit; operculum externally smooth. Natica (Tectonatica) clausa Broderip and Sowerby Text Figure 11 Natica clausa Broderip and Sowerby, Zool. Journ., Vol. 4, p. 360, 1829; Zool. Beechey's Voyage, p. 136, pi. 34, fig. 3, pi. 37, fig. 6, 1839; Wood, Mon. Palaeontographical Soc, Vol. 1, p. 147, pi. 16, figs. 2a, 26, 1848; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 77, 1868-9; Jeffreys, Ann. Mag. Nat. Hist., Ser. 4, Vol. 11, p. 206, 1872; Verrill, .\mer. Journ. Sci., Ser. 3, Vol. 5, p. 472, 1873; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 30, pi. 9, fig. 65, 1886; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 253, 1888; Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896; Berry, Nautilus, Vol. 22, p. 38, 1908; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 590, 593, 594, 597, 598, 1913; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 257, 1916; Dall, Journ. Wash. Acad. Sci., Vol. 9, p. 2, 1919; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 93, 1922; Meek, Vol. 14, p. 418, 1923. Natica (Cryptmiatica) clausa Broderip and Sowerby, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 313, pi. 10, fig. 13, 1903; Reagan, Trans. K.ansas Acad. Sci., Vol. 22, p. 224, pi. 6, fig. 63, 1909; Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 44, 1916; Dall, U. S. Nat. Mus., Bull. 112, p. 163, pi. 14, fig. 11, 1921; I. S. Oldroyd, Stan- ford Univ. Publ. Geo!., Vol. 2, Pt. 3, p. 122, pi. 97, fig. 2, 1927. Natica clausa Deshayes, S. Tokunaga, Journ. Coll. Sci., Imperial Univ. Tokyo, Vol. 21, p. 17, pi. 1, fig. 31, 1906. Natica (Cryptonatica) consors Dall, U. S. Geol. Surv., Prof. Paper 59, p. 86, pi. 5, fig. 10, pi. 6, fig. 9, 1909. ? Natica (Neverita) convexa Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 86, pi. 7, figs. I, 2, January 20, I9I6. Shell of medium size, globose, smooth; sutures abutting; spire slightly elevated; whorls about four, evenly convex or slightly shouldered. Height, about 2|7 mm.; width, 25 mm.; aperture, 20 X 123/2 mm.; deflection, 15°. Miocene: Astoria, Oregon (Dall); Montesano formation of western Washington (Weaver); Empire formation of Coos Bay, Oregon (Dall; Arnold and Hannibal; Howe). Pliocene: Lower Pliocene of Elsmere Canyon, Los Angeles County, one specimen (H. R. G.); upper Wildcat formation of Humboldt County, and Merced and Purisima formations of middle California (Martin) ; ? Etchegoin of middle California (Nomland, as convexa); British Crag (Wood); Coos conglomerate of Oregon (Arnold and Hannibal; Howe); "Fernando" of Los Angeles (Moody); S. D. S. N. H. locality 218, upper Pliocene east of South Mountain, Ventura County, five specimens (H. R. G.); Packard's Hill and Bath-house Beach, Santa Barbara (Arnold) ; etc. 798 San Diego Society of Natural History [Memoirs Pleistocene: Near Tokyo, Japan (Tokunaga); "Pliocene" of Deadman Island and Timm's Point, Los Angeles County, rare (Arnold); Rockheath, Hampton, and Billockby, England (Wood); lower San Pedro of Deadman Island, very rare (Arnold); Peard Bay, Alaska (Meek). Recent: Arctic and Bering seas, south in gradually deejiening water, to Japan on the west and San Diego, California, on the east (Dall, 1921); Arctic off northern Europe and Greenland, south in the Atlantic to Massachusetts and off Portugal in deep water (Tryon). This species is easily distinguished by its small, completely closed umbilicus, its globose shape, and abutting sutures. Polinices reclusianus, the most common species of this family on the California coast, varies from higher to shorter than clausa, but it is usually more conical in shape. P. reclusi- anus is further distinguished by its larger umbilicus, its much larger callus (which seldom completely fills the umbilicus and never is so closely united with the umbilical wall as in N. clausa), its tangential sutures and its usually larger size, to say nothing of its horny operculum. The figures by Dall (1921) and Oldroyd are easily accessible. Mr. George Willett, who has done considerable collecting of lonaiica) clausa Broderip and Rcccnt shells in the Alaskau region, points out that Natica clausa sowerby. Recent specimen y^^^ probably been coufouuded with N. russa Gould, which has from the Oldroyd Collection i ^ at Stanford University; natu- a siiiillar, but larger shcll, of a light brownish color, with a larger callus plug in the umbilicus. N. clausa is relatively rare in the Recent fauna of the northern part of the Pacific coast. Possibly some of the fossil records here grouped under clausa should be referred to russa. The figures of A^. convexa Nomland show a shell with the shape of N. russa except that the umbilical callus has a slightly different appearance. Perhaps partial decortica- tion has changed the appearance of the callus. Perhaps the form is a variant of Polinices reclusianus. For the present, the writers, although they have not found an opportunity to examine authentic specimens,' believe that it is more probably a variant of russa or clausa than of reclusianus, and hence have tentatively placed it here. Howe, who studied numerous specimens from the type locality of N. consors Dall, concluded that all these specimens represent N. clausa. A number of other synonyms or possible synonyms have been omitted from the above synonymy, as they would require more study than can be devoted to them at this time. Natica (Tectonatica) russa Gould Natica russa Gould, Proc. Boston Soc. Nat. Hist., Vol. 7, p. 43, June, 1859; Dall, Proe. Calif. Acad. Sci., Vol. 5, p. 251, 1874; Lowe, Nautilus, Vol. 18, p. 20, 1904. Cryptonatica aleutica Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 352, 1919. Natica aleutica Dall, Journ. Washington Acad. Sci., Vol. 9, p. 2, 1919. Cryptonatica aleutica Dall, Proc. Biol. Soc. Wash., Vol. 32, p. 251, Dec. 31, 1919. Natica (Cryptonatica) russa Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 163, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 123, 1927. Natica (Cryptonatica) aleutica Dall, U. S. Nat. Mus. Bull. 112, p. 164, pi. 14, fig. 10, 1921; I. S. Oldroyd, Univ. Wash- ington, Publ. Puget Sound Biol. Sta., Vol. 4, p. 161, pi. 22, fig. 12, 1924; Stanford Univ. Publ. Geol, Vol. 2, Pt. 3, p. 123, 1927. "Natica (Cryptonatica) clausa Broderip and Sowerby," I. S. Oldroyd, Univ. Washington, Publ. Puget Sound Biol. Station, Vol. 4, pi. 3, fig. 3 (not the text), 1924; not of Broderip and Sowerby. Type specimens: Of russa?; of aleutica, in U. S. National Museum. Type locality: Of russa, Arctic Ocean; of aleutica, Unalaska, Alaska, Recent. < The type, which is now at the University of California, came from the Etchegoin Pliocene northeast of Coalinga, California. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 799 Pliocene: St. George Island, Pribilof group (Dall, 1919); probably of many localities in California, listed as clausa. Pleistocene: Probably many localities listed as clausa. Recent: Bering Sea south to Catalina Island, California; also to Kamchatka and Japan. This species attains a larger size than Natica clausa. It also has a distinctive brownish color and a larger callus plug than Broderip and Sowerby's species with which it has been undoubtedly confused. Mr. Willett, of the Los Angeles Museum, has a series of A^. russa which well illustrates the uselessness of the name aleutica. Genus POLINICES Montfort, 1810 Polinices Montfort, Conch. Syst., Vol. 2, p. 222, 1810; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 87, 1909; Marwick, Trans. New Zealand Inst., Vol. 55, pp. 549, 559, 1924; Stewart, Proc. Acad. Nat. Sci., Phila., Vol. 78, p. 325, 1927; Woodring, Carnegie Inst., Publ. No, 385, p. 385, 1928. "Polynices Montfort," Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 367, 1892. Type (by original designation), Polinices albus Montfort (= Helix mamillaris Linna?us, 1767, + Natica brunnea Link, figured by Tryon, Man. Conch., Ser. 1, Vol. 8, p. 43, pi. 18, fig. 74, 1886), West Indies, Recent. Shell ovate to subcylintlrical; sutures generally tangential; aperture with a tliiek parietal callus coalescing with the fuiiicle and invading the umbilicus, which is sometimes completely filled, some- times left widely open; opercuhim corneous. (Marwick.) The shape, suture, size of the umbilicus, and nature of the umbilical calluses, as well as the corneous (instead of shelly) operculum, are useful in separating this genus from Natica. The parietal callus is much larger than in Natica. In this genus, and to some extent in the other genera of the Naticidce, there is a noticeable difference in the shells of the two sexes. The females are larger, with more inflated shoulders below the suture. Subgenus POLINICES, s. s. Shell oval or suboval, solid, smooth; aperture semilunar, imier lip oblique, callous, callus extend- ing mto and more or less completely filling the umbilicus (Tryon, Manual, description of Mamma Klein, a pre-Lumsean name). This subgenus is characterized by its ovate or subcylindric shape with tangential sutures and smooth outline, but its limits are not always clearly defined. Polinices (Polinices) uber (Valenciennes) Text Figure 12 Natica uber Valenciennes, Humboldt's Voy., Vol. 2, p. 266, 1833; d'Orbigny, Voy. Amer. Merid., p. 401, pi. 55, figs. 12-14, 1840, fide DaU, 1909; Reeve, Conch. Icon., Vol. 9, Natica, pi. 13, figs. 54a, 546, 1855; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 48, pi. 17, fig. 61, 1886; Hanna, Proc. Calif. Acad. Sci., Ser. 4, Vol. 14, p. 451, 1926. Polinices uber Valenciennes, Baker, Nautilus, Vol. 16, p. 41, 1902; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 235, 1909; Nautilus, Vol. 32, p. 24, 1918. Pliocene: Coyote Mountain, Imperial County (Hanna). Text figtoe 12. PoUnicesuber Pleistocene: Magdalena Bay (Dall, 1918), west coast of Lower California, the (Valenciennes), a typical Po(- Galapagos Islands, and Payta, Peru (Hanna). inices. Recent specimen from Recent: San Martin Island, Lower California, Mexico (Baker), to Callao, Peru, Lower California in the Old- , ,, _ , T . . ,T.v ,1 . „ , royd Collection at Stanford and the Galapagos Islands (Dall, 1909). University; natural size. 800 San Diego Society of Natural History [Memoirs Polinices (Polinices) bifasciatus (Gray) Nalica bifasciata Gray, in Griffith's Cuvier, Anim. Kingd., Moll., p. 598, pi. 1, fig. 2, 1834; Reeve, Conch. Icon., Vol. 9, Natica, pi. 10, figs. 40o, 406, 1855; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 44, pi. 18, fig. 75, 1886; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. Pliocene: Coronados Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Acapuico, Guaymas, and Cape San Lucas, Lower California, Mexico (Tryon). This Mexican species is well figured by Reeve and Tryon. It is probable that Polinices ramonensis (Clark) from the Oligocene and Polinices arnoldi (Clark) from the upper Miocene of middle California belong here. Possibly also Polinices inezanus (Com-ad) from the Miocene of California and Oregon is a Polinices, s. s., instead of a Neverita. Subgenus NEVERITA Risso, 1826 Neverita Risso, Hi.st. Nat. Eur. Merid., Vol. 4, p. 149, pi. 4, fig. 43, 1826; Mar^v-ick, Trans. New Zealand Inst., Vol. 55, p. 549, 1924. Type (by monotypy) , Neverita josephina Risso ( = N. olla de Serres) . Shell ovate; sutures tangential, appressed; apertural callus thick, coalescing with a huge funicle, which fills the umbilicus; aperture greatly inclined (Marwick). The greater inclination of the aperture, the more conical shape, and the larger umbilicus more sohdly filled by the funicle distinguish this subgenus from Polinices, s. s. Polinices (Neverita) reclusianus (Deshayes) Text Figures 13o, 136, 13c Natica rednsianaDeshayes, Rev. Zool. Soc. Cuv., p. 361, 1839; Guerin's Mag. de Zool., MoUusca, pi. 37, 1841; Reeve, Conch. Icon., Vol. 9, Natica, pi. 1, fig. 3, 1855; Sowerby, Thes. Conch., Vol. 5, p. 76, pi. 1, fig. 6, 1883. Neverita recluziana Deshayes, H. and A. Adams, Gen. Rec. MoU., Vol. 1, p. 208, 1853; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 77, 1868-9. Neverita recluziana Petit, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; Dall, Proc. Calif. Acad. Sci., Ser. 1, Vol. 5, p. 297, 1874; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 254, 1888; Keep, West Coast SheUs, p. 46, fig. 26, 1888, 1892; Eldridge and Arnold, U. S. Geol. Surv., Bull. 309, pp. 25, 28, 107, 152, 153, pi. 38, fig. 6, 1907; Arnold and Anderson, Bull. 322, p. 59, pi. 21, figs. 14a, 14b, 15, 1907; Weaver, Univ. Calif. Publ. Geol., Vol. 5, p. 265, 1909; Arnold, Bull. 396, U. S. Geol. Surv., pp. 25, 26, 31, 35, 40, 44, pi. 20, fig. 2, Jan. 15, 1910; Arnold and Anderson, Bull. 398, pp. 110, 130, 133, pi. 42, fig. 2, 1910; Smith, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 176, 1912; English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914. Natica (Neverita) recluziana. Petit, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 34, pi. 12, fig. 1, 1886; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 211, 1892; Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 423, 1915; Vol. 9, p. 15, 1915; Nomland, p. 203, 1916; Martin, p. 257, 1916; Moody, Vol. 10, p. 44, 1916; Clark, Vol. 11, p. 167, 1918. Polynices (Neverita) recluziana Deshayes, Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 369, 1892. Pohjnices (Neverita) reduziana Petit, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 314, pi. 10, fig. 12 (not tjT^ical), 1903. Polinices (Neverita) reduzianus Deshayes, Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 236, 1909; U. S. Nat. Mus., Bull. 112, p. 165, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 129, 1927; Hertlein and Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 630, 1927. Natica recluziana Petit, Nomland, Univ. Calif. Publ. Geol., Vol. 10, pp. 221, 301, 1917; Wagner and Schilling, Vol. 14, pp. 244, 245, 248, 1923; Kew, U. S. Geol. Surv., Bull. 753, pp. 78, 88, 1924. Polinices recluziana Deshayes, Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 150, 151, 1924. Neverita reclusiana (Deshayes), Pilsbry, Nautilus, Vol. 42, p. 109, pi. 6, fig. 1, April, 1929. Shell solid, conically globose, variable m shape; whorls four, in most cases only three visible when the outer shell layer is intact; callus very large, fillmg the posterior angle between the outer hp and the body whorl and extending around the columellar edge of the large uml)ilicus in a tongue- shaped mass, coalescing with another mass which extends over the rest of the umbilicus from about VoLr^rE I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 801 the middle of the inner Kp, the two calluses separated by a more or less distinct shallow groove, the calluses completely covering over the lunl^Uicus or leaving only a rounded hole at the outer an- terior corner, the calluses bounded by an impressed edge next to the umbihcal wall; size variable, Hke the shape. Average dimensions: Long. 30 mm., lat. 20 mm., or vice versa. Text figube 13. Polinices (Xeierita) Teclicsianus (Deshayes), typical variety, Recent specimen in the Oldroyd Collection at Stanford University; natural size. Fig. 13a, apertural view; fig. 136, side \'iew; fig. 13c, basal view. Oligocene: San Lorenzo formation or series of middle California (Clark); of the San Emigdio region, San Joaquin basin, Oligocene in part (Wagner and Schilling). Miocene: Vaqueros formation (Arnold, 1910; Eldridge and Arnold); Temblor formation (Arnold and Ander- son, 1907, 1910); Santa Margarita and San Pablo formations (Cooper; Arnold; Arnold and An- derson; Weaver; Smith; Nomland; Clark; etc.); Isidro formation, lower Miocene of Arroyo San Ignacio, Lower California, Mexico (Hertlein and Jordan). Pliocene: Lower part (Cooper; Arnold; Smith; English; Nomland; etc.); middle (DaU, 1S74; Arnold; Martin; Nomland; etc.); upper (.Arnold, 1903; Moody; Martin; Kew; etc.); — reported from nearly every locality treated in the literature. Pleistocene: Santa Barbara, San Pedro, San Diego (Cooper; Arnold, 1903); — common nearly everywhere. Recent: Crescent City, California, south to the Tres Marias Islands, Mexico (Dall); ? Chile (Philippi). This variable species has been reported in abundance from many localities along the Pacific coast, especially in California, from the Oligocene to the Recent. It has appeared in the hterature under a great many specific and varietal names, most of them of very Uttle or no significance; but in order to clarify the situation and bring out what value (if any) there may be in the distinctions, the varieties are here briefly reviewed. The species, as a whole, is of some value as an indication of temperature, not being found today north of California. Variety reclusianus, s. s. See references under the species, also: Neverita recluziana alia DaU, Proc. U. S. Nat. Mus., Vol. 1, pp. 12, 27, 1878, no description; Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 221, 1917. Polinices {Neverita) recluziana, var. alia Dall, U. S. Geol. Surv., Prof. Paper 59, p. 88, 1909; not "Neverita recluziana var. alta Dall," .Arnold, IT. S. Geol. Surv., Bull. 396, pp. .32, 36, 40, pi. 20, figs. 5, 5a, 1910, nor BuU. 398, pp. 127, 130, pi. 42, same figures, which is another variation; Dall, U. S. Nat. Mus., Bull. 112, p. 165, 1921; Oldroyd, Stanford Tniv. Publ. Geol., Vol. 2, Pt. 3, p. 130, 1927. Pliocene: Etchegoin formation of Coalinga region (.Arnold) ; upper Sargent and lower Merced of some middle Cahfornia localities (Nomland) ; lower Pliocene of Elsmere Canyon and east of Fernando Pass; middle Pliocene (Pico) of Holser Canyon and southeast of Pico Canyon (H. R. G.). Pleistocene: Lower San Pedro of Nob Hill cut (T. S. Oldroyd), and upper San Pedro series at several localities in San Pedro region (Arnold), Los Angeles County. Recent: Monterey to San Diego and Catalina Island, California. 802 ■ San Diego Society of Natitral History [Memoirs The typical variety' has a comparatively high, conical shape with a blunt apex. The portion of the body whorl just below the suture is concave. It is figured by Reeve, Sowerby, Tryon, etc., but not by Arnold, 1903, 1907, 1910. The typical variety seems to show distinctly the difference between the male and female shapes, the former, which is probably the variety alius Dall, is even taller and more slender than usual. The females are considerably more numerous than the males. P. redusianus, s. s., has probably been present from the Oligocene to the Recent, but is said to be less common in the older formations. Polinices (Neverita) redusianus (Deshayes) variety andersoni (Clarlv) ? Polynices (Neverita) reduziana Petit variety alia Dall, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 315, 1903. "Neverita callosa Gabb," Anderson and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 43, 1914. "Neverita reduziana Petit, t3T)ical form," Arnold, in various papers on California stratigraphy (see references under reduzianiis, all except Arnold, 1903, in part, which is, in part, variety callosus (Gabb). Nalica (Neverita) reduziana andersoni Clark, Nomland, Vol. 10, p. 301, 1917, nomen nudum cited as "Clark (MS.)"; Clark, Univ. Calif. Publ. Geol., Vol. 11, o. IBS. d1. 20, figs. 3, 10, 11, 12, 1918. Oligocene to Pliocene: (Clark). Pliocene: S. D. S. N. H. localities 202-207, 209, 210, Elsmere Canyon lower Pliocene; 215, 216, east of Fer- nando Pass; also various other localities in the lower and some in the middle Pliocene of the Santa Clara Valley region, Los Angeles and Ventura coimties (H. R. G.); etc. Pleistocene: S. D. S. N. H. locality 235, between Aliso and Hampton canyons (U. S. G.) ; locality 236, east of Harmon Canyon (11. S. G.); locality 243, Adams Canyon (H. R. G.), all Ventura County; etc. Recent: This form is apparently even more common than the typical in the Recent fauna. This variety, though still somewhat conical, has a lower spire than typical redusianus, a sharper apex, the body whorl below the suture sloping off at a low angle and curving around broadly, with constantly increasing convexity, to the umbilicus. The shoulder that Clark speaks of is very inconspicuous on the specimens figured by him and is lacking on many other specimens which are otherwise the same. This variety does not have the concave portion of the body whorl just below the suture that is characteristic of the typical form, except in specimens that are leaning toward the typical form, and in them it is only slightly developed. Polinices (Neverita) redusianus (Deshayes) variety pabloensis (Clark) ? Natica ocoyana Conrad, U. S. Pacific R. R. Repts., Vol. 5, p. 328, pi. 7, figs. 57, 57a in text (51, 51a by misprint on plate), 1855. Nalica (Neverita) pabloeitsis Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 488, pi. 68, figs. 12, 14, 1915. Miocene: San Pablo and Briones formation (Astrodapsis hrewerianus zone) of middle California (Clark). Pliocene: S. D. S. N. H. locality 206, Elsmere Canyon, one specimen from the upper echinoid horizon (H. R. G.) ; middle Pliocene of Canada de las Encinas, Ventura County, one specimen, and southeast of Pico Canyon, Los Angeles County, three specimens (H. R. G.); etc. ' Pilsbry's paper on "Neverita redusiana (Desh.) and its Allies" (Nautilus. Vol. 42, pp. 109-113, pi. 6. 1930) came to our attention after the manuscript on the Naticidse had been completed and it was then too late to re-examine the collections. According to Pilsbry, the form called altus by Dall is a valid species and the variety imperforata a valid variety, both, however, subject to some uncertainty. We have examined a large series of specimens of Polinices redusianus and its allies, and we believe imperforatus is of no taxonomic value whatsoever, the intergrades being common in large collections. The shells which Pilsbry assigns to alius (as a distinct species) are not the same as the ones referred to above as alius. They have a deep brown umbilical callus, which might be characteristic of a southern race. We do not recall having seen intergrades between the shells with a brown and those with a white umbilical callus, this difference in color appearing to be the 'most distinctive difference, if the form is at all valid. We seriously question its value. Pilsbry proposes the new section Glossaulax for the species with the groove in the umbilical callus, a prominent feature on most Recent specimens of this clan. The groove is often not clearly developed on caliosus Gabb, though it is clearly shown in Gabb's figure. The section Ghssaulax appears to have originated in the early Ter- tiary, probably in the middle or lower Eocene. In the Recent fauna it occurs on both sides of the Pacific Ocean. Polinices redusianus (Des- hayes) is the type of Glossaulax by original designation. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 803 This variety has a lower spire than variety andersoni, and the last part of the body whorl forms a table which slopes down very gradually to the rounded shoulder. It may be the same as ocoyanus (Conrad), but insufficient material from Ocoya Creek has made identification with that form uncertain. Polinices (Neverita) reclusianus (Deshayes) variety callosus (Gabb) Text figure 14 Xeverita callosa Gabb, Geol. Surv., Calif., Palaeo., Vol. 2, p. 10, 1866, pi. 2, figs. 17, 17o, 17b, 1S68-9; Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 542, pi. 44, figs. 4, 4a, 1907; U. S. Geol. Surv., Bull. 398, pp. 85, 86, 1910; not of Ander- son and Martin, Proc. Calif. Acad. Sci., Ser. 4, Vol. 4, p. 43, 1914, fide Clark. Pohjnices {Necerila) reduziana Petit, "typical shape," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 314, in part, pi. 10, fig. 12, 1903. Polinices (Neverila) reduziana Deshayes var. vancouverensis Clark and Arnold, Univ. Calif. Publ. Geol., Vol. 14, p. 169, pi. 33, figs. 2a, 26, 3, 1923. Oligocene: Sooke formation, Washington (Clark and Arnold). Miocene: Ranges throughout the Miocene (Arnold, 1907); Vaqueros formation (Arnold, 1910); Topanga Canyon, Los Angeles County (U. S. G.). Pliocene: Lower Pliocene of S. D. S. N. H. localities 206 and 232, and Piru Creek below mouth of Holser Canyon, Los Angeles County; doubtfully in the Pliocene of O'Hare Canyon, Ventura County, and southeast of Pico Canyon, Los Angeles County (localities 223, 228, (H. R. G.)). Pleistocene: Barlow Canyon, two specimens (U. S. G.) ; etc. Recent: A few specimens in the Recent fauna conform to the characters of this variety. This variety is like variety andersoni except that it is always smoothly rounded and the spire is sunken down even with, and is almost concealed by, the upper portion of the body whorl. The callus usually completely covers the umbilicus, though sometimes there is a small, rounded perforation. The type of vancouverensis (Clark and Arnold) is a reclusianus, variety callosus, leaning toward andersoni. text figche u. PoUnices rr\-i 'i?? •• •imii/' • (Neverita) reclusianus (Des- i he variety callosus is quite common in the Temblor formation hayes) variety miiome (Gabb) , in Topanga Canyon. Specimens obtained from there show a r^yrStettTon^irst'nf!!^ variation in the height of spire as well as in the character of the university; natural size, tus umbihcal callus. The groove on the umbilical callus of the ardeXi". '^tTo^d Ip^Ir Topanga Canyon specimens is sometimes nearly obsolete. ""'''! ^^^^" " "°' '"'''* "p '° Subgenus EUSPIRA Agassiz in Sowerby, 1838 Euspira Agassiz, in Sowerby, Min. Conch. Gt. Brit., German Ed., pp. 14, 320, 1838, fide Sherborn, Index .\nim.. Sect. 2, p. 2250, 1926; Agassiz, in Desor, Sowerby's Min. Conch., French Ed., pp. 14, 15, 16, 1839, fide St«wart, 1927; DaU, BuU. Mus. Comp. Zool., Harvard Coll., Vol. 43, p. 333, 1908; U. S. Geol. Surv., Prof. Paper 59, p. 87, 1909; Marwick, Trans. New Zealand Inst., Vol. 55, p. 568, 1924; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 324 and footnote, 1927. Lunalia Gray, Proc. Zool. Soc. London for 1847, p. 149, 1847. "Naticina Guilding," Fischer, Man. de Conchyl., p. 766, 1885, not of Guilding, Trans. Linn. Soc. London, Vol. 17, p. 30, 1834. Labellinacca Cossmann, Conch. Neog. Aquit., Vol. 3, p. 392, 1919; Ess. Paleo. Comp., Vol. 13, p. 137, 1925. Not "Euspira Agassiz, 1837," Cossmann, Ess. Pal6o. Comp., Vol. 13, pp. 50, 133, 138, 1925. Type (by subsequent designation, Dall, 1908, 1909), Natica glaucinoides Sowerby, not Deshayes (= ? Natica labellata Lamarck). Sowerby's species is from the Eocene of England. 804 San Diego Society of Natural History [ Memoirs Shell globose; spire moderate; outer lip straight, slightly retracted to suture, inclmed about 30° from vertical; inner margm with light caUus on parietal wall; umbihcus open and without any funicle; operculum horny. (Marwick.) Neither the French nor the German editions of Sowerby's Mineral Conchology have been available to the present authors. The original references given above have been taken from Sherborn and Stewart. Contrary to Marwick's description, the species lewisii often has a large parietal callus. It is distinguished from Neverita by the underdeveloped funicle, which leaves the umbilicus open. Polinices (Euspira) lewisii (Gould) Text Figures 15a, 156 15a 15b Text figure 15. Polinices {Euspira) lewisii (Gould), Recent specimen in tlie Oldroyd Collection at Stanford University: natural size. Fig. 15a, apertural view; fig. 156, basal view. Natica leinsii Goiild, Proc. Boston Soc. Nat. Hist., Vol. 2, p. 239, 1847; Rept. U. S. Expl. Exped., Vol. 12, p. 211, 1852, Atlas MoU., pi. 15, fig. 253, 1856; Martin, Univ. Calif. Publ. Geol., Vol. 9, p. 257, 1916, as "Natica, near lewisii Gould." Lmuitia lewisii Gould, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 661, 1864; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 77, 1868-9; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 35, pi. 13, fig. 11, 1886; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 247, 1888; Keep, West Coast Shells, p. 45, fig. 25, 1888, 1892; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 374, 1892; Arnold, U. S. Geol. Surv., Bull. 322, p. 58, pi. 21, fig. 3, 1907; Bull. 396, pp. 25, 26, 31, 35, 39, pi. 22, fig. 1, 1910; .^nold and Anderson, Bull. 398, pp. 109, 110, 127, 129, 133, pi. 44, same figures, 1910. Polynices (Lunalia) lewisii Gould, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 315, pi. 10, fig. 14, 1903. Polinices leunsi Gould, Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 325, pi. 38, fig. 1, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 150, 1924. Polinices (Euspira) lewisii Gould, DaU, U. S. Nat. Mus., Bull. 112, p. 165, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, p. 127, 1927. Shell of large size, only moderately heavy, sub-globose or conico-globose ; whorls sLx, ventricose, with sutures abutting, shoulders high on the whorls, rounded, on the mature whorls with a concave flexure on the side of the whorl, nearly parallel to the suture; umbilicus moderately long, deep, with a slight encroachment down the right wall. Dimensions (from Gould): Axial diameter, 4V2 to 5 inches; transverse diameter, 4 inches. Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 805 1 Miocene: Ivirker's Pass, Contra Costa County (Cooper, as Pliocene). Pliocene: Listed questionably in the Jacalitos formation, lower Pliocene of Coalinga region (Arnold and Anderson); Wildcat, Etchegoin, Merced, Purisima, and Sargent formations of middle California (Martin, listed as a species near lewisii); Soquel, Santa Cruz County (.Arnold); upper Etchegoin of Coalinga region (Arnold and Anderson); Fernando of Santa Maria district, Santa Barbara County (Arnold, 1907); west of Fernando Pass, one doubtful fragment (H. R. G.); San Fernando, Los Angeles County (Cooper). Pleistocene: Lower part of the Pleistocene series in Adams Canyon, Ventura County, three specimens (H. R. G.); Santa Barbara; San Nicolas Island (Cooper); rare in the upper San Pedro series of San Pedro, Los Cerritos, Long Beach, Crawfish George's, and Deadman Island, Los Angeles County (Arnold, 1903). Recent: Duncan Bay, British Columbia, to Santa Barbara Island, California (Dall, 1921); San Diego Bay (collection of Fred Baker). This very large species is larger, less globular, and higher spired than P. draconis Dall. The slight, concave flexure on the side of the body whorl is also a distinguishing character. It is distinguished from P. galianoi Dall of the Oregon Miocene by its more ventricose whorls, more elevated spire, and the flexure on the body whorl. It can be most easily distinguished from reclusianus by its abutting sutures, more convex shoul- ders, and open umbilicus. The young can be distinguished from N. clausa only by the umbilical callus and the operculum. Polinices (Euspira) galianoi Dall Polinices (Euspira) galianoi Dall, U. S. Geol. Surv., Prof. Paper .59, p. 88, pi. 5, figs. 12, 13, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 591, 593, 1913; Howe, Univ. Calif. Publ. Geol., Vol. 14, p. 93 and table opposite, 1922. Polynices galianoi Dall, Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 32, 1916. Shell of moderate size, rather tliick, moderately elevated; sutures abutting but with a slight tendency to be tangential; whorls about sLx, with comparatively straight sides and rounded shoul- ders; umbihcus moderate, open, its upper angle near the pillar lip filled mth a small subtriangular callus; aperture ovate, narrowed above, a thin callus on the body. Dimensions about half those of lemisii, with the maximum transverse diameter longer than the axial. Miocene: Montesano formation of western Washington (Weaver); Empire formation of Coos Bay, Oregon (Dall; Arnold and Hannibal). Pliocene: Merced-Purisima of middle California (Arnold and Hannibal); S. D. S. N. H. locality 204, lower Pliocene of Elsmere Canyon, Los Angeles County, one poor specimen, questionably this species (H. R. G.). Pleistocene: Barlow Canyon, Ventura County, one specimen. This form is smaller and of different shape from lewisii, but it may be only a variety or variation of it. Some fossils, especially small forms, of lewisii lack the faint flexure on the side of the body whorl. Both this form and draconis are difficult to distinguish from lewisii. Polinices (? Euspira) orbicularis (Nomland) Natica {Neverita) orbicularis Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 207, pi. 10, figs. 4o, 4fc, 1916; Moody, Vol. 10, p. 44, pi. 2, fig. 6, 1916; Nomland, Vol. 10, p. 221, 1917. Pliocene: Common in the Chione elsmerensis zone and Turrilella noca zone, and rare in the Pecten coalingensis zone of Coalinga region; lower and upper Sargent, Purisima, and lower Merced of middle California (Nomland); Fernando of Los Angeles (Moody). This form is most probably an immature or stunted variation of lewisii, and the name should be synonymized. 806 San Diego Society of Natural History [ Memoirs Genus SINUM Bolten, 1798 Sinum Bolten, Mus. Boltenianum, Pt. 2, p. 14, 1798; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 91, 1909; U. S. Nat. Mus., Bull. 90, p. 109, 1915; Woodring, Carnegie Inst., Publ. No. 385, p. 389, 1928. Sigaretvs Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 77, 1799, monotype, Helix haliotmdes Linnseus. Type (by subsequent designation, Dall, 1915), Helix haliotoides Linnaeus. Shell ear-shaped or Naticoid, spire small, low; body whorl rapidly enlarging, with a very large aperture; sculpture consisting of fine revolving grooves, sometimes crossed by curved growth lines; operculum small, homy, subspiral. Sinum scopulosum (Conrad) Sigaretus scopvlosvs Conrad, U. S. E.xpl. Exped., Geol., p. 727, pi. 19, figs. 6, 6a only, 1849; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 380, 1892; Dall, in Diller, U. S. Geol. Surv., 17th Ann. Kept., Pt. 1, p. 474, 1896; F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 3, Vol. 2, pp. 188, 203, pi. 16, figs. 72, 73, 1905; Arnold, U. S. Geol. Surv., Prof. Paper 47, pp. 17, 19, 1906; Reagan, Trans. Kansas Acad. Sci., Vol. 22, pp. 172, 194, pi. 3, fig. 30, 1909; Arnold, U. S. Geol. Surv., Bull. 396, p. 32, pi. 24, fig. 1, 1910; Arnold and R. Anderson, BuU. 398, p. 127, pi. 44, same figure, 1910; F. M. Anderson, Proc. Calif. Acad. Sci., Ser. 4, Vol. 3, p. 100, 1911; J. P. Smith, p. 176, 1912; Anderson and Martin, Vol. 4, p. 43, 1914. Catimis scop^dosvs Conrad, Meek, Smithsonian Misc. Coll., No. 183, p. 31, 1864; Conrad, Amer. Journ. Conch., Vol. 1, p. 151, 1865. SloTtiaiia scopulosa Conrad, Meek, op. cit., p. 31, 1864. Simivi scopulosvm Conrad, Meek, op. cit., p. 32, 1864; Gabb, Geol. Surv. Calif., Palao., Vol. 2, p. 114, 1868-9; Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 12, 18, 91, 92, pi. 4, fig. 10, pi. 5, fig. 8, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 584, 588, 1913; English, Univ. Calif. Publ. Geol., Vol. 8, p. 211, 1914; Clark, Vol. 9, p. 15, 1915; Vol. 11, p. 169, pi. 22, fig. 8, 1918; Trask, Vol. 13, pp. 153, 154, 1922; Kew, U. S. Geol. Surv., Bull. 753, p. 78, 1924; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, pp. 327, 328, pi. 32, fig. 4, 1927. Sinum planicostum Gabb, Geol. Surv. Calif., Pateo., Vol. 2, pp. 49, 78, pi. 14, fig. 6, 1868-9; Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 91, 92, 1909. Sigaretus planicosttiin Gabb, Cooper, Calif. State Mining Bureau, Bull. No. 11, p. 80, 1896; .\jiderson, Proc. Calif. Acad. Sci., Ser. 3, Vol. 2, p. 204, 1905. ? Sinum {Sigaretus) trigenarium Trask, Univ. Calif. Publ. Geol., Vol. 13, pp. 139, 142, 146, 153, pi. 7, figs. 2a, 26, 1922, fide Stewart, 1927. Sinum califcrmicum I. S. Oldroyd, Nautilus, Vol. 31, p. 13, 1917; DaU, U. S. Nat. Mus., Bull. 112, p. 165, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 19, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 130, pi. 92, figs. 13, 14, 1927. Shell of moderate size, Naticoid, of about three rapidly enlargmg whorls; body whorl large, aperture ample, ovoid, longest diameter at about an angle of 45° from axis of spire; outer lip simple, no obvious callus process on body whorl ; sculpture consisting of spiral channels separating strap-like surfaces, the channels farther apart near the top of the body whorl, finer and closer together near the base ; growth Imes on the body whorl crossing spiral sculpture ; suture distinct, obliquely abutting, sometimes nearly tangential near the apex of the spire. Diameter of body whorl, average, about 32 mm. Oligocene: San Ramon formation of Contra Costa County (Clark). Miocene: Empire formation of Oregon (DaU) ; San Pablo and Santa Margarita formations of middle Cali- fornia (Nomland). Pliocene: Etchegoin formation of the Coalinga region (Nomland); lower "Fernando" of Los Angeles County (English); lower Pliocene of Elsmere Canyon and middle Pliocene of Pico and Holser canyons, Los Angeles County (H. R. G.); etc. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los Angeles County (T. S. Oldroyd). Recent: Monterey, California, to Todos Santos Bay, Lower California, Mexico (Dall, as S. calif omicum). Sinum debile (Gould) Sigaretus debilis Gould, Journ. Boston Soc. Nat. Hist., Vol. 6, p. 379, pi. 14, fig. 17, 1853; Carpenter, Proc. Zool. Soc. London for 1S56, p. 207, 1856; Tryon, Man. Conch., Ser. 1, Vol. 8, p. 57, pi. 24, fig. 65, 1886; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 264, 1888; Keep, West Coast SheUs, p. 47, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 316, 1903. Sinum debile Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 165, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 131, pi. 92, figs. 3, 7, 1927. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 807 Pliocene: San Diego well, San Diego (Cooper). Pleistocene: Palisades north of Santa Monica (collection of F. C. Clark) ; rare in upper San Pedro series of Los Cerritos and of the lumber yard at San Pedro (Arnold). Recent: Catalina Island, California, to Gulf of California, Mexico (DaJl, 1921). This species has a very flat shell, which is much smaller than mature shells of scopulosu7ti. The shell is the opposite extreme from that of Sinum. perrini (Arnold), a species of the Temblor formation (Miocene), coming from the head of Topanga Canyon, Los Angeles County, and having a peculiar, axially elongated shell very unlike that of other California Sinums. The Recent specimens of Sinutn scopulosum (Conrad) were formerly erroneously classified in collections as S. debile, but the two species are entirely distinct. Genus AMAUROPSIS Morch, 1857 Amauropsis Morch, Rink's Gr^nland, geographisk og statisk beskrevet, App., p. 81, 1857; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 89, 1909; Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 3.32, 1927; Woodring, Carnegie Inst., Publ. No. .385, p. 393, 1928. Type (by subsequent designation, Dall, 1909), Natica helicoides Johnson ( = ? Nerita islandica Gmelin), figured by Tryon, Man. Conch., Ser. 1, Vol. 8, p. 53, pi. 22, fig. 31, 1886, Arctic Ocean, Recent. Shell axially elongate, imperforate, suture canaliculate, shell walls tliin. This is a northern cold and cool-water group not represented in the tropics. Wood- ring has shown that the tropical American species which have been sometimes assigned to Amauropsis belong to a different group, which he names Pachycrommium.^ Amauropsis oregonensis (Dall) Ampullina (Amauropsis) oregonensis Dall, U. S. Geol. Surv., Prof. Paper 59, p. 91, pi. 3, fig. 7, 1909. Ampullina oregonensis Dall, Arnoki and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, pp. 588, 590, 1913; Weaver, Univ. Wash. Publ. Geol., Vol. 1, p. 30, 1916. Oligocene: Blakeley formation of western Washington (Weaver). Miocene: Empire formation of Coos Bay region, Oregon (Dall; Arnold and Hannibal). Family VELUTINIDAE Genus VELUTINA Fleming, 1821 Velulina Fleming, New Edinburgh Encyclopedia, American Edition, Vol. 13, Pt. 2, article on MoUusea, p. 684, Phila- delphia, 1821; Gray, Proc. Zool. Soc. London for 1847, p. 156, 1847. Galerimdum Brown, Illust. Conch. Gt. Brit. Ire., pi. 38, figs. 35, 38, 1827. Type (by original designation and absolute tautonymy), Bulla velulina Miiller, Zoologia Danica, Ed. 3, Vol. 3, pi. 101, figs. 1-4, 1789, -I- Velulina vulgaris Fleming, = Helix Icevigata of British authors, = Helix Icevigata Linnaeus. Velutina laevigata (Linnaeus) Helix Ixvigata Linnaeus, Syst. Nat., Ed. 12, p. 1250, 1767. Galericulum Isevigalum Linnseus, Brown, lUust. Conch. Gt. Brit. Ire., pi. 38, figs. 35, 38, 1827; Ed. 2, p. 23, pi. 19, figs. 35, 38, 1844. Velutina Isvigala Linnaeus, Forbes and Hanley, Hist. Brit. Moll., Vol. 3, p. 347, pi. 99, figs. 4, 5, 1851 ; Sowerby, Conch. Man., Ed. 4, pi. 15, fig. 337, 1852; Fischer, Man. de Conchyl., p. 763, pi. 8, fig. 7, 1885. Velutina Isevigata Pennant, Tryon, Man. Conch., Ser. 1, Vol. 8, p. 65, pi. 27, figs. 41-44, 48, 59, 1886; Dall, Journ. Wash. Acad. Sci,, Vol. 9, p. 2, 1919. Velutina Ismgata (Linnaeus) Miiller, Dall, U. S. Nat. Mus., Bull. 112, p. 167, 1921. ^ Type, by original designation (Woodring, op. cit., p. 391, 1928) Amaura guppyi Gabb, figured by Woodring. pi. 31, figs. 7, 8; Miocene of Dominican Republic, 808 San Diego Society of Natural History [Memoirs Pliocene: "Late Pliocene" of St. George Island, Pribilof group (Dall, 1919). Recent: Icy Cape, Arctic Ocean, to Monterey, California; also Atlantic (Dall, 1921). Tryon regarded Helix laingata of Linnaeus a "lost species," but he used the name as of Pennant (Brit. ZooL, p. 140, pi. 86, fig. 139, 1777). "Bulla" velutina Muller (Zool. Dan., Prod., p. 242, 1776) may be a synonym. The synonymy of laevigata is large, but has been omitted from the above list of references. The animal is entirely contained within the shell of this species, whereas in most of the other Pacific species the animal covers the shell. For this reason the epidermis of Icevigata is rough and sometimes minutely spinose. V. prolongata Carpenter has a smooth, shiny epidermis made so by the animal entirely covering the shell. In passing, it may be well to call attention to Vehdina rubra Willett,' which appears to be a valid species overlooked by Dall and by Oldroyd in their catalogues of Recent shells of the Pacific coast of North America. It is a small species with a very incon- spicuous spire. The living animal is of a bright vermillion color. There are four para- types in Mr. Willett's collection, which is now on deposit in the Los Angeles Museum.^ Superfamily Docoglossa Family LEPETIDAE Genus LEPETA Gray, 1842 Lepeta Gray, S3aiop. Cont. Brit. Mus., Ed. 42, p. 148, 1840, nomen nvdum, fide Sherborn, Index Aiiim.; Gray, Ed. 44, p. 67, 1842, diagnosis, no species, fide Iredale, Proc. Malac. Soc. London, Vol. 10, p. 306, 1913; Gray, Proc. Zool. Soc. London for 1847, p. 168, 1847, type Patella cxca; Dall, Amer. Journ, Conch., Vol. 5, p. 140, pi. 15, figs. 1, la, \h, If, Id, 1870; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, pp. 67, 68, 1891. Type (by monotypy), Patella cceca Muller, Zool. Dan., Prod., p. 237, 1776, figured by Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 13, p. 68, pi. 40, figs. 29-32, 1891. Shell patellifonn, the embryonic nucleus spiral, lost in the adult; apex in front of the middle; no internal septum. Animal without external branchiae; having the muzzle produced into a labial process on each side. Dental formula 2.0.1.0.2, the uncLni narrow, erect, provided with cusps. (Pilsbry.) Section Cryptobbanchia Middendorff, 1851 Cryptobranckia Middendorff, Reise Auss. Norden und Ost. Sibiriens, Vol. 2, p. 183, 1851; Dall, Amer. Journ. Conch., Vol. 5, p. 143, 1870; Proc. U. S. Nat. Mus., Vol. 1, p. 334, 1878; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 13, pp. 67, 68, 1891. Cryptoctenidia Dall, Proc. U. S. Nat. Mus., Vol. 54, p. 233, April 5, 1918, new name for Cryplobranchia Middendorff, not Gray, 1821. Type {fide Dall, 1870), C. concentrica Middendorff. Apex inclmed forward, the anterior terminations of the muscle-scar not in front of it. Surface not grtuiulate; color whitish. Apex of rhachidian tooth tricuspidate, the cusps nearly equal; imciai spatulate. (Pilsbry.) Cryptobranckia was used by Gray before Middendorff proposed it as a generic name; but Gray's usage was applied to a higher classification and does not preoccupy the name in a generic sense. ' Nautilus, Vol. 33, p. 25, July, 1919, type locality, Forrester Island. Alaska. 2 The type specimen was sent by Mr. Willett to the Academy of Natural Sciences of Philadelphia but through some oversight no mention of it was made in the original description of the species. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 809 Lepeta concentrica (Middendorff) Patella {Cryplobranchiii) cxca, var. co7iccntrica Middendorff, Reise Auss. Nord. Ost. Sibiriens, Vol. 2, p. 183, pi. 16, fig. 6, 1851, fide Dall, 1870. "Cryptobranchia concentrica Dall ex Midd." Dall, Amer. Journ. Conch., Vol. 5, p. 143, pi. 1.5, figs. 2a-g, 1870. Cryplobranchia alba Dall, op. cil., p. 145, pi. 15, figs. 3a-d, 1870. ? Cryptobranchia instabilis Dall, op. cil., p. 145, pi. 15, fig. 6, 1870. Lepeta concentrica Middendorff, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 69, pi. 40, figs. 33-37, 1891. Cryptoctenidia concentrica Middendorff, Dall, U. S. Nat. Mus., Bull. 112, p. 168, 1921. Cryploctenidia alba Dall, op. cit., p. 168, 1921 . Cryptoctenidia alba instabilis Dall, op. cit., p. 168, 1921. Lepeta (Cryptoctenidia) concentrica Middendorff, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 142, 1927. Lepeta (Cryptoctenidia) alba Dall, I. S. Oldroyd, op. cit., p. 143, 1927. Lepeta (Cryptoctenidia) alba instabilis Dall, I. S. Oldroyd, op. cit., p. 143, 1927. Pliocene or Pleistocene: Mouth of Elk River, Oregon, and one specimen from Cape Blanco, Oregon (collection at Stanford University). Recent: Icy Cape, Arctic Ocean; on the west to Okhotsk Sea and Shantar Islands, on the east to Forrester Island, Alaska (Dall, 1921), Puget Sound (Oldroyd). This shell varies greatly in shape. A series of Recent specimens convinces us that alba and instabilis are of no taxonomic importance whatsoever. Specimens which Mr. Willett collected in Alaska at low tide line are stained a Hght gi-eenish color, the deep-water shells being whitish. The fine radial striae are apparent usually only on young or unworn individuals. Lepeta magna (DaU) Cryptoctenidia magna DaU, U. S. Geol. Surv., Prof. Paper 125-C, p. 30, pi. 5, fig. 1, 1920. Pliocene: Center Creek, \]/2 miles north of Nome, from the "second beach"; prospect holes in the "second beach," }^ to J^ mile east of Nome; also Center Creek mines, 2 miles northwest of Nome, Alaska (Dall). Family ACMAEIDAE Shell patelliform, conical, the apex more or less anterior, the embryonic shell conical, not spiral. Animal having a free branchial plume above the neck on the left side; radula without median teeth. (Pilsbry.) In addition to anatomical differences, the Acmoeidoe differ from the Lepetidoe and Patellidce by the more or less distinct internal border of the aperture. They are never iridescent within.' Genus ACMAEA Eschscholtz in Kotzebue, 1830 Aansia Eschscholtz, in Kotzebue, Neue Reise um die Welt in den Jahren 1823, '24, '25, and '26, Vol. 2, Appendi.x, p. 24; English translation. Vol. 2, Appendix, p. 350, London, 1830, genus without species (fide Woodring, 1928); Eschscholtz, in Rathke, Zool. Atlas, Pt. 5, p. 16, 1833; Dall, Amer. Journ. Conch., Vol. 6, p. 238, 1871; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 7, 1891; Woodring, Carnegie Inist., Publ. Xo. 385, p. 458, 1928. , Type (by subsequent designation, Dall, 1871), Aanoea mitra Eschscholtz. This genus has a number of synonjmas which have been given by Pilsbry (1891), hence, need not be repeated here. ^ The reader is referred to Pilsbry's excellent treatment of the family Acmxidse in Volume 13 of Tryon's Manual of Concholoj^y. 1891. 810 San Diego Society of Natural History [Memoirs Acmaea mitra Eschscholtz in Rathke Aans:a mitra Eschscholtz, in Rathke, Zool. Atlas, Pt. 5, p. 18, pi. 23, fig. 4, 1833; Dall, Amer. Journ. Conch., Vol. 6, p. 241, 1871; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 228, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 24, pi. 3, fig. 50, 1891; Keep, West Coast Shells, p. 99, fig. 85, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 318, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908; E. P. and E. M. Chace, Lor- quinia, Vol. 2, p. 42, 1919; Dah, U. S. Nat. Mus., BuU. 112, p. 168, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 144, pi. 85, fig. 5, 1927; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 253, 1929. Aanxa mammillala Eschscholtz in Rathke, op. cit., p. 19, 1833. Actnsea marmorea Eschscholtz in Rathke, op. oil., p. 19, 1833. Pliocene: Upper Pliocene at Bath-house Beach, Santa Barbara (Berry). Pleistocene: Santa Barbara to San Diego (Cooper); Crawfish George's, near San Pedro, "not uncommon" (Arnold) ; chiton bed on Point Firmin, Los Angeles County (Chace) ; at the old "coal mine" and other late Pleistocene localities on the west side of Point Loma, San Diego (Stephens). Recent: Pribilof Islands, Bering Sea, to San Diego, California (Dall, 1921). This is a large, white, variable shell easily distinguished from the other California species of Acmcea. Some specimens support a nodular growth of calcareous algse, which mislead Eschscholtz into distinguishing them as marmnillata. Acmcea funiculata Carpenter, 1864 (+ tenuisculpta Carpenter, 1866), generally treated as a variety of Acmcea mitra, may be a distinct species. It possesses axial ribs, of which there is not a trace on A. mitra. Acmaea cassis Eschscholtz in Rathke variety pelta Eschscholtz in Rathke Acmsea pelta Eschscholtz, in Rathke, Zool. Atlas, Pt. 5, p. 19, 1833; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 228, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 17, pi. 8, figs. 90, 91, 1891; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 319, 1903; DaU, Nautilus, Vol. 28, p. 14, June, 1914; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 253, 1929. Acma-a (Collisella) pelta Eschscholtz, Dall, Amer. Journ. Conch., Vol. 6, p. 246, pi. 14, fig. 6, 1871. Type locality: Sitka, Alaska, Recent. Pleistocene: Santa Barbara (Cooper); Barlow's Ranch, near Ventura; rare in lower San Pedro series of Dead- man Island; upper San Pedro series of Los Cerritos and San Pedro (Arnold); Point Firmin chiton beds (Chace); Pacific Beach, San Diego (Arnold); at the mouth of the abandoned "coal mine" and other localities on the west side of Point Loma, San Diego (F. Stephens). Recent: Okhotsk and southern Bering Sea, Nushagak, Alaska, the Aleutian Islands, south to Rosario Bay, Lower California, and Socorro Island (Dall, 1921). The radiating ribs of the variety pelta are not so well developed as those of the typical variety. Both forms occur on the same rock in Alaska, and it is likely that pelta should be synonymized. Acmaea limatula Carpenter Patella scahra Nuttall, Reeve, Conch. Icon., Vol. 8, Patella, pi. 37, figs. 119a-6, 1855, not of Gould, 1846. Aansea scahra, Nutt., var. limatula Carpenter, Amer. Journ. Conch., Vol. 2, p. 340, 1866. Acmsea scahra NuttaU, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 228, 1888; not A. scahra (Gould). Acmsea scahra Reeve, var. limatvla Carpenter, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 14, pi. 3, figs. 38-40, 1891. Acmsea limatula Carpenter, Dall, Nautilus, Vol. 28, p. 14, 1914; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; DaU, U. S. Nat. Mus., BuU. 112, p. 170, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 19, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 152, 1927; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 253, 254, 1929. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro (T. S. Oldroyd); at the Point Firmin chiton bed (Chace), Los Angeles Coimty; at the mouth of the abandoned "coal mine" and various other localities on the west side of Point Loma, also south of La JoUa, San Diego (Stephens). Recent: Crescent City, California, south to Cedros and Socorro islands, Lower California, Mexico (DaU, 1921). Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 811 Acmaea scabra (Gould) Patella (LolHa ?) scabra Gould, Proc. Boston Soc. Nat. Hist., Vol. 2, p. 152, 1846. Patella spectrum Nuttall, Reeve, Conch. Icon., Vol. S, Patella, pi. 29, figs. 76a-6, 1855. Acvisea spectrum Nuttall, Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 228, 1888," Keep, West Coast Shells, p. 100, figs. 86, 87, 1888, 1892; West American Shells, p. 230, fig. 252, 1904; Ed. 2, p. 216, fig. 209, 1911. Acms'a spectrum (Nuttall) Reeve, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 320, 1903. Acmaea spectrum Reeve, Pilsbry, Trjon's Man. Conch., Ser. 1, Vol. 13, p. 14, pi. 1, figs. 7, 9, 1891. Acmxa scahra Gould, Dall, Nautilus, Vol. 28, p. 14, 1914; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; DaU, U. S. Nat. Mus., Bull. 112, p. 170, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 19, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 153, 1927; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 2.53, 1929. Pleistocene: Santa Barbara and San Pedro (Cooper) ; rare in lower San Pedro series of Deadman Island and rather common in the upper San Pedro series of Deadman Island and San Pedro (^\rnold); lower San Pedro series of Nob Hill cut, San Pedro (T. S. Oldroyd) ; in the chiton bed at Point Firmin (Chace), Los Angeles County; at the mouth of the old "coal mine" and other nearby localities on the west side of Point Loma, San Diego (Stephens). Recent: San Francisco, California, to Socorro Island, Lower California, Me.xico (Dall, 1921); Puget Sound (collection of Fred Baker). The prominent, rugose radiating ribs of this common Recent species serve to dis- tinguish it from most other Pacific coast limpets. Acmaea persona Eschscholtz in Rathke Acmcea persona Eschscholtz, in Rathke, Zool. Atlas, Pt. 5, p. 20, pi. 24, figs. 1, 2, 1833; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 228, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 15, pi. 2, figs. 25-28, pi. 3, figs. 51-56, 1891; Dall, Nautilus, Vol. 28, p. 14, 1914; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1921; Dall, U. S. Nat. Mus., Bull. 112, p. 170, 1921; not of Carpenter, 1864. Pleistocene: At the fossil chiton bed on Point Firmin, Los Angeles County (Chace). Recent: Shumagin Islands, Alaska, to Socorro Island, Lower California, Mexico (Dall, 1921). Pilsbry has given a number of synonyms of this species. Acmaea insessa (Hinds) Patella insessa Hinds, Ann. Mag. Nat. Hist., Ser. 1, Vol. 10, p. 82, pi. 6, fig. 3, 1S42. Nacella incessa Hinds, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 650, 1864; Keep, West Coast Shells, p. 103, fig. 91, 1888, 1892. Acmsa insessa Hinds, Dall, Amer. Journ. Conch., Vol. 6, p. 244, pi. 14, fig. 3, April 4, 1871; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 227, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. IS, pi. 6, figs. 36, 37, 1891; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 318, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 170, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 19, 1925; F. Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, pp. 253, 254, 1929. Ac7na?a iucessa Hinds, Keep, West American Shells, p. 234, fig. 258, 1904; Revised Ed., p. 220, fig. 215, 1911; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 1.56, 1927. Type locality: San Diego, California, "on sea-weed. Pliocene: Upper Pliocene at the Bath-house Beach outcrop, Santa Barbara (Arnold). Pleistocene: "Pliocene" of Deadman Island; lower San Pedro series of Deadman Island and San Pedro (Arnold) ; lower San Pedro series of Nob Hill cut, San Pedro (T. S. Oldroyd) ; upper San Pedro series of Deadman Island, San Pedro, Los Cerritos, and Crawfish George's (Arnold) ; at the Point Firmin chiton bed (Chace); Spanish Bight (Arnold) and on west side of Point Loma (Stephens), San Diego. Recent: Trinidad, California, to Magdalena Bay, Lower California, Mexico, on kelp (Dall, 1921). 812 San Diego Society of Natural History [Memoirs Acmaea asmi (Middendorff) Patella (Acmara) asmi Middendorff, Bull. Phys. Math. Acad. Imp. Sci. St. Petersb., Vol. 6, p. 318, November, 1847 Patella asmi Middendorff, Beitr. Malac. Rossica, Vol. 1, Pt. 2, p. 39, pi. 1, fig. 5, 1849. Collisella asmi Middendorff, Dall, Amer. Journ. Conch., Vol. 6, p. 252, pi. 14, fig. 7, 1871. Acmxa asmi Middendorff, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 19, pi. 6, figs. 38, 39, 1891; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; Dall, U. S. Nat. Mus., Bull. 112, p. 170, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 157, pi. 94, figs. 15, 16, 1927. Pleistocene: At the chiton bed on Point Firmin, Los Angeles County (Chace). Recent: Sitka, Alaska, to San Diego, California, and Socorro Island, Mexico, "on black Tegulas" (Dall, 1921). Acmasa depicta (Hinds) Patelloida depicta Hinds, Ann. Mag. Nat. Hist., Ser. 1, Vol. 10, p. 82, pi. 6, fig. 4, 1842; Zool. Voy. Sulphur, p. 53, 1844. Nacella depicta Hinds, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 650, 1864. Collisella (f) depicta Hinds, Dall, Amer. Journ. Conch., Vol. 6, p. 254, 1871. Acmsea depicta Hinds, Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 13, p. 19, pi. 6, figs. 40, 41, 1891; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 317, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 170, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 157, 1927. Type specimen: In the British Museum ? Type locality: San Diego, CaHfornia; Recent. Pleistocene: Ujiper San Pedro series at Crawfisli George's, "one specimen" (Arnold), Los Angeles County. Recent: Santa Barbara, California, to Lower California, Mexico, "on Zostera" (Dall, 1921). This is a small, narrow, elongate species that Uves on sea weed. The direct influence of habitat on the shape of the shells of the Acmceidce is so great that probably many forms of distinctive appearance and separate names are mere ecologic variants. A. depicta has brown bands radiating from the apex. It is similar to A. paleacea Gould, but the latter form is much narrower and lacks the radial brown color bands of depicta. A. tri- angularis (Carpenter) has bright radiating color bands and is much larger and rounder than either. Acmaea paleacea Gould Acmsea paleacea Gould, Mex. and Calif. Shells, p. 3, pi. 14, fig. 5, 1851; Boston Journ. Nat. Hist., Vol. 6, p. 376, pi. 14, fig. 5, 1853; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 13, p. 20, pi. 6, fig. 42, 1891; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 319, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 171, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 158, 1927. Collisella paleacea Gould, DaU, Amer. Journ. Conch., Vol. 6, p. 253, 1871. Pleistocene: Upper San Pedro series of Crawfish George's, Los Angeles County, "two' specimens found" (Arnold). Recent: Trinidad, California, to Lower California, Mexico, on Zostera (Dall, 1921). Acmaea rudis Gabb Acmxarudis Gabb, Geol. Surv. Calif., Pateo., Vol. 2, pp. 51, 87, pi. 14, fig. 9o, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 228, 1888. "Acmxa' rudis Gabb, Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 313, pi. 32, figs. 11, lln, 1927. Type specimen: In the Whitney Collection, Museum of Comparative Zoology, Harvard University. Type locality: "Pliocene of San Fernando, near Wiley's." Pliocene: At the type locality (Gabb; Cooper). Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 813 Stewart, who carefully studied Gabb's types of California fossil mollusks, was unable to recognize the muscle scar as shown by Gabb, and it is possible that this species is a Calyptrcea or a Crucibulum. If so, the species would require a new specific name, unless, of course, Gabb's form is conspecific with some other already named species. Acmaea instabilis (Gould) Plate 32, Figure 32 Patella instabilis Gould, Proc. Boston Soo. Nat. Hist., Vol. 2, p. 150, 1846. Nacella instabilis Gould, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 650, 1864; Keep, West Coast Shells, p. 103, 1888, 1892. Acmsa instabilis Gould, DaU, Amer. Journ. Conch., Vol. 6, p. 245, 1871; Pilsbry, in Tryon's Man. Conch., Ser. 1, Vol. 13, p. 18, pi. 6, figs. 32, 33, 1891; Cooper, Calif. State Mining Bureau, Bull. 4, Pt. 3, p. 24, 1894; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 318, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 170, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 156, pi. 94, figs. 1, 2, 1927. Type specimen: In the New York State Museum, Albany, No. 6,356, fide Oldroyd. Type locality: Neah Bay, Washington; Recent. Pleistocene: Upper San Pedro series at Crawfish George's, near Fort McArthur, Los Angeles County, one specimen (Arnold) ; questionably at San Nicholas Island (Cooper, as of Bowers) ; upper Pleistocene at S. D. S. N. H. loc. 74, southwest of Goleta, Santa Barbara County (U. S. G.). Recent: Kodiak Island, Alaska, to San Pedro, California (DaU, 1921); San Diego (collection of Fred Baker). The habitat of this species on the large stalks of kelp accounts for the elongate oval shape, with the basal margins at each end turned up. Superfamily Rhipidoglossa Family PHASIANELLIDAE Shell bulimiform or subglobose, polished, without epidermis or nacre, variegated with bright colors; operculum heavj-, calcareous, internally paucispiral, with nucleus near the basal margin, externally convex, white. (Pilsbry, 1888.) Genus TRICOLIA Risso, 1826 Tricolia Risso, Hist. Nat. Eur. Merid., Vol. 4, p. 122, 1826; Gray, Proc. Zool. Soc. London for 1847, p. 144, 1847, misspelled "Tricolea"; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 167, 1888; Woodring, Carnegie Inst., Publ. No. 385, p. 418, 1928. Type (by subsequent designation. Gray, 1847), Turbo pullus Linnaeus, figured by Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 168, pi. 38, figs. 56-60, 1888, European Seas, including the Mediterranean, Recent. In a recent paper, Woodring (1928) has completely separated Tricolia Risso from Phasianella Lamarck, placing the former in a distinct family, Tricoliidce. As the basis of separation is largely one of great difference in the sizes of the respective genotypes, the two genera are here retained in the one family. The type of Phasianella Lamarck,^ according to Woodring,^ is Buccinum australe Gmelin, wliich is a giant in comparison with the California Recent and fossil species that have been called Phasianella, and it appears natural to make a generic distinction in this case. ' Ann. Mm. Hiat. Nat. Paris, Vol. 4. p. 295, 1804. » See Woodring's discussion of the designation of the type of the genus. Phasianella australis (Gmelin) is a Recent species of Australia. It is figured by Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 164, pi. 37, figs. 22-2S, pi. 38. fig. 46, 1888. 814 San Diego Society of Natural History [Memoirs Tricolia compta (Gould) Phasianella compta Gould, U. S. House of Representatives, Document 129, Prelim. Rept., p. 25, 1855; U. S. Pacific R. R. Repts., Vol. 5, p. 11, figs. 25, 26, 1857; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 258, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 321, 1903; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Phasianella {Tricolia) compta Gould, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 173, pi. 39, fig. 69, 1888; Dall, U. S. Nat. Mus., Bull. 112, p. 171, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 161, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Phasianella (Tricolia) compta Gould, variety producla Dall, Proc. U. S. Nat. Mus., Vol. 34, p. 256, 1908; Strong, Proc. Calif. Acad. Sci., Ser. 4, Vol. 17, p. 191, pi. 10, fig. 1, 1928. Tricolia compta produda Dall, U. S. Nat. Mus., Bull. 112, p. 172, 1921. Pleistocene: "Saugus" formation near Ventura (Waterfall) ; lower San Pedro series at San Pedro and Deadman Island; common in upper San Pedro series of San Pedro, Los Angeles Coimty; foot of Twenty-sixth Street, San Diego (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Gulf of California, Mexico (Dall, 1921). Mr. A. M. Strong suggests that Arnold's Pleistocene records may refer to puUoides (Carpenter). T. compta is an inhabitant of bays and lagoons. It is larger than T. pulloides, which occurs along the open coast in tide pools and on sea lettuce. Tricolia pulloides (Carpenter) Phasianella compta Gould, ? var. puUoides Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 651, 1864. Phasianella (? compta, var.) pulloides Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 180, March, 1865. Phasianella compta Gould, var. pulloides Carpenter, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 173, pi. 39, fig. 70, 1888. Tricolia pulloidea Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 172, 1921. Phasianella pidloides Carpenter, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Phasianella (Tncolia) pulloides Carpenter, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 162, 1927; Strong, Proc. Calif. Acad. Sci., Ser. 4, Vol. 17, p. 192, pi. 10, figs. 5, 6, 7, 1928. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Lower California, Mexico (DaU). Most of the individuals of Tricolia pulloides that are commonly found in some places along the southern California coast on sea lettuce are immature, the adults living in deeper water. The species has a smaller shell than compta, adults averaging about five millimeters in length, whereas compta is often over 8 millimeters. Section Eulithidium Pilsbry, 1898 Eucosmia Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 475, June, 1864; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 177, 1888; not Eucosmia J. F. Stephens, lUust. Brit. Ent., p. 265, 1831, Lepidoptera. Eulithidium Pilsbry, Nautilus, Vol. 12, p. 60, September, 1898, new name for Eucosmia Carpenter, 1864, not Stephens, 1831; Index to Tryon's Man. Conch., in Vol. 17, p. 319, under Eucosmia, October, 1898, ^e p. 348; Dall, Proc. U. S. Nat. Mus., Vol. 34, p. 255, 1908. Type (by subsequent designation, Pilsbry, 1888), Eucosmia variegata Carpenter, (not P. variegata Lamarck), + Tricolia substriata (Carpenter), variety typica (Dall). Shell solid, shining, variegated, not nacreous; aperture and whorls rounded; conspicuously umbilicated ; peritreme scarcely continuous, not callous. (Carpenter.) Tricolia substriata (Carpenter) Eucosmia {? variegata, var.) substriata Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 475, June, 1864. Phasianella (Eucosmia) variegata Carpenter, var. substriata Carpenter, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 177, no figure, 1888. Eulithidium suhslriaium Carpenter, Berry, Nautilus, Vol. 21, p. 45, 1907; Dall, U. S. Nat. Mus., Bull. 112, p. 172, 1921. Volume II PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 815 Phasianella substriala Carpenter, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. PhasianeUa {Eulithidium) snhslriala Carpenter, I. S. Oldroyd, Stanford Vniv. Publ. Geol., Vol. 2, Ft. 3, p. 16.3, 1927. Type locality: Cape San Lucas, Lower California, Mexico; Recent. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Catalina Island, California, to Panama (Dall); Monterey Bay, California (Berry). Tricolia variegata (Carpenter) Eitcosmia variegala Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 13, p. 47.5, June, 1864; not Berry, Nautilus, Vol. 21, p. 45, 1907; not Phasianella variegala Lamarck. Phasianella {Encosmia) variegata Carpenter, Pilsbry, Tryon's Man. Conch., Ser. 1, \'ol. 10, p. 177, no figure, 1888. Eulithidium typicvm Dall, Proc. V. S. Nat. Mus., Vol. 34, p. 255, June 16, 1908, new name for Eucosmia variegata Carpenter, not Phasianella variegata Lamarck; Dall, V. S. Nat. Mus., Bull. 112, p. 172, 1921. Phasianella {Eulithidium) typica Dall, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 162, (not pi. 91, fig. 9, = P. ruhrilineala Strong, 1928) 1927; Strong, Proc. Calif. Acad. Sci., Ser. 4, Vol. 17, p. 194, pi. 10, figs. 12, 13, 1928. Type locality: Cape San Lucas, Lower California, Mexico. Recent: Magdalena Bay to Cape San Lucas, Lower California, Mexico (Strong, 1928). This species is the genotype of Eulithidium Pilsbry. It is a smooth shell somewhat similar to puUoides but has an open umbilicus. The paper by Strong above referred to will be found very helpful in distinguishing the California Recent species. As pointed out by Woodring', Ball's name is unnecessary if Tricolia is separated generically from Phasianella. Family TURBINIDAE Shell turbinate or troehiform, solid, pearly within, smooth or sculptured without; operculum calcareous, heavj% circular or elongated, flat, and covered with a thin horny layer within, convex, calcareous and smooth or rugulose outside; the opercular nucleus multispiral, subcentral, or marginal. The Turbinidce differ from the Trochidce, particularly in the possession of a calcareous operculum, and also in other characters. The Phasianellidce do not have a nacreous shell within. In general, the Turhinidw are inhabitants of tropical and temperate seas in the lit- toral zone or at shallow depths. They are herbivorous. Genus TURBO Linnasus, 1758 Turho Linojeus, Syst. Nat., Ed. 10, p. 761, 1758; Montfort, Conchyl. Syst., Vol. 2, pp. 202-204, 1810, type T. petholatus; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, pt. 2, p. 191, 1888; W^oodring, Carnegie Inst., Publ. No. 385, p. 408, 1928. Senedus Swainson, Treat. Malac, p. 348, 1840, as of Humphrey. Lseviturbo Cossmann, Ess. Paleo. Comp. , Vol. 11, p. 118, 1918, type, T. petholatus Linnseus. Type (by subsequent designation, Montfort, 1810), Turbo petholatus Linnaeus, Indo- Pacific; Recent. Shell large or moderate in size, turbinate; whorls rounded, smooth, or ribbetl, spinose or car- inated, umbilicate or imperforate; aperture subcircular, more or less produced at base. Operculum circular, with subcentral nucleus; outside convex, granulate, or smooth, not spiral nor ribbed. (Pilsbry.) As pointed out by Woodring, Turbo marmoratus Linnaeus has generally been con- sidered the type of the genus because it was the species chosen by Lamarck in the Pro- drome as an example of Turbo. Since Lamarck's selections of examples in this work are not considered type designations, Montfort's choice of Turbo petholatus Linnaeus is the earliest valid selection. ' Woodring, Carnegie Inst. Wash., Publ. No. 385. p. 420, 1928. 816 San Diego Society of Natural History [Memoibs Subgenus CALLOPOMA Gray, 1850 Calloponia Gray, Figs. Moll. Anim., Vol. 4, p. 87, 1850; Pilsbry, Tryon's Man. Conch., Vol. 10, p. 210, 1888; Cossmann, Ess. Paleo. Comp., Vol. 11, p. 116, 1918. Type, Turbo flucluatus Gray, fide Cossmann, 1918. Shell turbinate, imperforate, dark colored; aperture round; face of the columella wdth a deep longitudmal groove. Operculum circular, with a subcentral apex; outside convex, granulose, with a deep central pit and a marginal cordon of granulose ribs, separated by narrow, deep concentric grooves. (Pilsbry.) It seems probable that the Turbo fluctuatus of Gray is the Turbo fluctuosus Wood,. 1828. Sherborn' suggests such a synonymy and it is certain that the Turbo fluctuatus of Reeve refers to Wood's species. Turbo (Callopoma) fluctuosus Wood Turho fludiiosus Wood, Index Testae, Supplement, pi. 6, fig. 44, 1828; Fischer, in ICiener's Spec. Gen. Icon. Coq. Viv., Vol. 11, Turho, p. 61, pi. 9, fig. 2, pi. 17, fig. 2, pi. 34, fig. 1 (?), 1873; E. K.Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, pp. 150, 152, 1924; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. f Trochus fokkesi Jonas, in Philippi, Abbild. Beschreib., Band 1, Trochus, p. 5, pi. 2, figs. 1, 10 (operculum), 1843. Turbo fluctuatus Reeve, Conch. Icon., Vol. 4, Turbo, sp. 34, pi. 8, fig. 34, March, 1848. Callopoma fluctuata Gray, Figs. Moll. Anim., Vol. 4, p. 87, 1850. Turbo (Callopoma) fluctuosus Wood, Mabille, Bull. Soc. Philomathique de Paris, Ser. 8, Vol. 7, p. 56, 1895; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 238, 1909. Turbo fluctuatus Gray, Cossmann, Ess. Paleo. Comp., Vol. 11, p. 116, pi. 3, fig. 13, 1918. Shell ovate-conic, short, sohd, imperforate, olivaceous, green, bro^\ai or grayish, longitudinally strigate or tesselate with white; spire conic; whorls five, generally angulate and nodose at shoulder, with a varying number of coarse subnodose revolving carmse and of intermediate lirulse upon the median and lower portions of the body whorl; aperture large, iridescent within; columella wide, white, slightly produced at the base, and with a longitudinal excavation or groove upon its face. Alt. 58, diam. 65 mill. (Pilsbry.) Pliocene: Coronados Island, Gulf of California, Mexico (Hanna and Hertlein). Pleistocene: Lower Quaternary, Magdalena Bay, and upper Quaternary of Scammons Lagoon, Lower Cali- fornia, Mexico (Jordan). Recent: Cedros Island, Lower California, and Gulf of California, Mexico, to Peru. This shell is noticeably variable in color and intensity of sculpturing. In the more strongly nodose forms it approaches the coronated variety saxosus. The operculum is flat and covered with a thin chestnut horny layer on the inside; externally it has an elevated spiral granulose rib with four or five parallel marginal rows of fine, comb-like tubercles. Turbo (Callopoma) fluctuosus Wood variety saxosus Wood Turbo saxosus Wood, Index Testae. Supplement, pi. 6, fig. 45, 1828; Fischer, in Kiener's Spec. Gen. Icon. Coq. Viv., Vol. 11, p. 23, pi. 15, fig. 2, pi. 16 bis, fig. 2, 1873; Hanna and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. ? Turbo fluctuosus Wood, in part only, of Fischer, in Iviener's Spec. Gen. Icon. Coq. Viv., Vol. 11, Turbo, pi. 16, figs. 1, 2 (?), also 16 bis, figs. 1, 2, 1873. Turbo {Callopoma) saxosus Wood, DaU, U. S. Nat. Mus., Vol. 37, p. 238, 1909. Pliocene: Coronados Island, Gulf of California, Mexico (Hanna and Hertlein). Recent: Mazatlan, Mexico, and south to Paita, Peru, and the Galapagos Islands (Dall). ' Index Animalium, Part 2, "Tvirbo, ? Wood, 1828." We have not seen the volume IV of Gray's work above referred to. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 817 This variety is carinated, usually nodose at the shoulder and with a series of erect tubercles below the suture. Turbo fopangensis Arnold, of the Temblor formation, lower part of the Monterey group, recalls Tedarius dilatatus d'Orbigny of the Recent fauna of Cuba, but it attains a larger size than the Cuban shells. It is quite unlike Tedarius galapagiensis Stearns' of the tropical fauna. Genus ASTRAEA Bolten, 1798 Aslrxa Bolten, Mus. Boltenianum, Ft. 2, p. 79, 1798; Suter, Man. Xew Zealand Moll., p. 166, 1913; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 92, April, 1909; Woodring, Carnegie In.st., Publ. No. 385, p. 412, 1928. Type (by subsequent designation, Suter, 1913), Trochus imperialis Gmelin ( = Trochus heliotropium Martyn) ; Recent, New Zealand. Shell trocliiform, generally depressed, flattened below; with or without an open umbUicus; basal periphery of whorls generally carinated, always so in the young; operculum calcareous, oval, or oblong, nucleus generally submarginal or terminal, multispiral, exterior almost smooth to coarsely ribbed. Size, up to several inches in diameter. Geologic range: Early Tertiary to Recent (Astrcea, s. I.). Woodring has shown that Astralium Link^ can be used as a section for the "West Indian Astrseas which have a narrow umbilicus or are entirely imperforate. The type of Astraea^ is widely umbilicate. The "AstrcBa Gmelin," 1789, of Agassiz in the Nomenclator Zoologicus (Fasc. 12, p. 38, 1847) is an error. Subgenus ASTRAEA, s. s. Umbilicus open; basal periphery of whorls carinated; operculum with eccentric nucleus, exterior smooth. The typical subgenus is not represented on the North American coast. Subgenus POMAULAX Gray, 1850 Pomaulax Gray, Fig. Moll. Anim., Vol. 4, p. 87, 18.50; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, pp. 187, 190, 1888. Type, Trochus undosus Wood. Shell large, conic, solid, imperforate; periphery carinated; base flattened; lunbihcal tract with a strong, curved rib; operculum obovate, narrower toward the proximal extremity, nucleus terminal, outside mth four strong granulose ribs radiating from the nucleus. (Pilsbry.) This subgenus is readily distinguished from Astrcea, s. s., by its imperforate axis, whereas the typical subgenus is widely umbilicate. Pachypoma Gray differs in its long and very convex operculum and the absent or very obscure semicircular ril) in the I Nautilus, Vol. 8, p. 87, 1892; Proo. U. S. Nat. Mus., Vol. 16, p. 396, pi. 51, fig. 7, 1893. ■ Besclireib. Natur.-Sammlung Univ. Rostock, p. 135, 1S07, type, AstraUum deplanatum Link (= Trochus costutatus Lamarck), desig- nated by Woodring, 1928. ' Hedley (Mem. Australian Mus., Vol. 4, p. 335, 1903) sought to supplant Astralhan Link with Calcar Montfort on the basis that Link's work was not properly published. This interpretation cannot be accepted. 818 San Diego Society of Natural History [Memoirs umbilical region. The oblong, strongly ribbed/ and partly granulose operculum of A. undosa is very different from the comparatively small, elongate, smooth, convex operculum of A. incequalis (Martyn), the type of Pachypoma. U vanilla Gray has fewer ribs on the outer surface of the operculum. This latter group is represented in the southern fauna by Astroea (Uvariilla) olivacea (Wood), buschi (Philippi), and unguis (Wood). Astraea (Pomaulax) undosa (Wood) Plate 31, Figures 6a, 66, 7 Trochiis undosus Wood, Index Testae, Supplement, p. 16, pi. .5, fig. 1, 1828. Pomaulax undosus Wood, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 6.51, 1864; Gabb, Geol. Surv. Calif., Pala;o., Vol. 2, p. 83, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 260, 1888; Keep, West Coast Shells, p. 89, fig. 75, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 199, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 322, 1903; Keep, West American Shells, p. 237, 1904. Imperator undosa Wood, Tryon, Struct. Syst. Conch., Vol. 2, p. 308, pi. 88, fig. 33, 1883. Aslralium (Pmnaidax) undosum Wood, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 243, pi. 58, figs. 69, 70, 1888. "Pachypoma inseguale Martyn," Williamson, Proc. U. S. Nat. Mus., Vol. 15, pi. 23, figs. 1, 5 (not fig. 3), 1892, not of Martyn. Aslrxa undosa Wood, Dall, Nautilus, Vol. 32, p. 24, 1918; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 149, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Astrs:a (Pomaidax) undosus Wood, DaU, U. S. Nat. Mus., Bull. 112, p. 172, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 164, pis. 102, 103, 1927. Shell large, conic; whorls about six, periphery with a prominent undulating nodose carina; base flattened, with five or si.x spiral ribs; aperture elongate-ovate, oblique, somewhat pearly within; columella arched, between which and the prominent spiral ridge in the umbilical region there is a crescentic depression; outer lip simple; sculpture consisting of undulating, somewhat nodose ribs, slanting approximately parallel to the slope of the left side of the spire, and also a prominent nodose, pre-sutural carma; m living specimens shell colorless or gray, covered with a horny, obliquely lamel- lose epidermis; operculum ol:)Ovate, very slightly convex inside, with a terminal nucleus, outside with three (four or five, comiting one or both raised margins) radiating, raised, granulose ridges. Large specimens measure: greatest diameter of base 140 mm., axial length 80 mm. Pleistocene: Santa Barbara to San Diego (Cooper) ; upper San Pedro series at San Pedro and Crawfish George's, Los Angeles County, and of Pacific Beach, San Diego (Arnold); Magdalena Bay, Lower California (Dall, 1918; Jordan, 1924, as "Lower Quaternary"); upper Pleistocene at San Quintin Bay, Lower California (Jordan, 1926). Recent: Laguna Beach, Orange County, southern CaUfornia, to Cedros Island, Lower California (Dall, 1921); ? San Pedro (Williamson — figured specimen fossil ?); more northern reports by Cooper, Arnold, and others questionable. This species has not been reported in beds older than the faunal break at the end of the Pliocene. Perhaps gradata changed over into undosa at that time. Astraea (Pomaulax) gradata, new species Plate 31, Figures la, 16, 3a, 36, 5, 8, 9 ? Pachypoma sp. Watts, Bull. 19, Calif. State Mining Bureau, p. 322, 1900; Eldridge and Arnold, BuU. 309, U. S. Geol. Survey, p . 24, 1907. Shell large, eccentrically conical, apical angle about 60°; whorls convex, about seven, sub- tabulate, the top of each whorl strongly abutting against the lowest, somewhat nodular ridge or carina of the preceding whorl, thence extending out nearly horizontally about 8 mm. to the first row of nodes ; below the uppermost row of nodes the surface sloping downward at an angle of about 45° past the middle of the whorl to the second row of nodes, where it drops off nearly vertically for about 6 mm. to the basal ridge; each vertical segment of the surface, especially the lowest, given a concave appearance by the projection of the spirally aligned nodes or ridges; upper nodes elongated * There are three prominent ribs radiating from the nuclear extremity, but the proximal margins are elevated, one or both of which might be counted as ribs, giving a count of four or five. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 819 obliquely, somewhat comma or crescent shaped, pointing forward and downward, 14 to a whorl; nodes of the second row, which are about as far below the center of the whorl as the upper row is above, somewhat more numerous and coalescing laterally to form a spiral ridge; basal ridge analogous to the strongly nodose keel of Astrwa undosa (Wood) but showmg verj' little tendency to be nodose and not projectmg beyond the second row of nodes; lower two ridges showing through as sharp angles on the cast, the upper row of nodes as faint undulations along a roimded shoulder; sutures distinctly impressed; base nearly flat, sculptured by three strong spiral ridges besides the basal ridge or carma on the angle of the whorl, which appears below much like the other spiral ridges of the base; inner lip covered with a fairly heavy callus; outer lip m every case missing, but the growth lines on the side of the whorl, which slope backward at an angle of about 45° and cross the upper row of nodes diagonally, showing the aperture to be like that of Astraa undosa. Operculum similar to that of undosa, but less elongate. Dimensions: Altitude 75 mm., diameter of body whorl 65 mm., height of body whorl 35 mm. Type specimen: Holotype No. 286, San Diego Society of Natural History. Type locality: Southeast of Pico Canyon, Los Angeles County, middle Pico Pliocene (H. R. G.). Pliocene: S. D. S. N. H. locality 228, southeast of Pico Canyon, Los Angeles County, the type specimen; loc. 217, Holser Canyon, Los Angeles County, one operculum; loc. 217a, nearby, two small speci- mens and a small operculum; loc. 217b, one figured paratyjie and the figured operculum, with three other specimens and three other opercula (coll. by H. R. G.); the forms identified by Merriam and listed by Watts came from localities not far from locality 217. Astraa gradata is distinguished from A. hiangulata Gabb^ by the fewer number of nodes per whorl (14 as a maximum in the upper row instead of 22 or more); by the prominent upper angle and tabulation, the upper row of nodes being only slightly drawn out and not so much like axial ribs as in hiangulata; by the basal carina, which is prac- tically continuous and shows almo.st no tendency to be nodose; and by the absence of the minor spiral line shown in hiangulata between the lower two rows of nodes. It is probable that "Astralium" raymondi Clark is only a small form of hiangulata, since they both come from the same beds; and Calliostoma bicarinatum Clark may be a very young form, since it also occurs in the same localities and is analogous in form to the young of A. gradata. This new species is distinguished from Astraea (Pomaulax) turbanica (Dall)^ of the Recent southern fauna by its larger size, its much less prominent and less rib-like upper row of nodes, and the more laterally elongate lower row of nodes. Also, A. turbanica has a much flatter base, which is more clearly set off from the lateral surface of the body whorl by the prominent nodose basal carina. The operculum, several specimens of which were found close to the shells, is of interest in showing that this species and also probably the closely related hiangulata Gabb from the upper Miocene belong to the subgenus Pomaulax. The name gradata refers to the step-like appearance of the cone, which is due to the steep slope of the whorls above the suture and the gentle slope below. Astrasa (Pomaulax) breaensis Carson Astraia breaensis Carson, Bull. So. Calif. Acad. Sci., Vol. 2.5, pt. 2, pp. 57, 58, pi. 4, figs. 3, 4, May 31, 1926. Type specimen: No. 116 in the type collection at Stanford University. Type locality: Mouth of Brea Canyon, Puente Hills, Orange County, California; Pliocene. » Geol. Surv. Calif., Palajo., Vol. 2, p. 15, 1866, p. 83, pi. 3, fig. 26, 1868-9, figured also by Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 318, pi. 32, fig. 6, 1927. 2 Pomaulax lurbanicus Dall, Nautilus, Vol. 23, p. 134. 1910. 36 fathoms, Magdalena Bay. Lower Califomia. See Plate 31, figure 2. showing DalPs type specimen. 820 San Diego Society or Natltral History [Memoihs "Shell small, conical, spire low, whorls about four; whorls sloping above, rounded on the sides and base, suture distinct, appressed; sculpture consisting of prominent rounded oblique ridges, about twenty on body whorl, with narrow mterspaces, extending from the side of the whorl to the suture above ; base of body whorl marked l)y four heavy, roimded, spiral ridges with narrower inter- spaces; aperture of moderate size, subcircular, outer lip simple, inner hp slightly thickened, umbUicus false. Height of type, 22 mm., maximum diameter of type, 41 mm., minimum diameter of type, 35 mm." Plinccrie: Fernando (lower or middle Pliocene) of Brea Canyon, Orange County, California. This species is quite distinctive, on account of its low spire, long protractive ribs, and the convex base of the body whorl. "Astralium" arnoldi Nomland is a Tegula, a member of the family Trochidce. Subgenus PACHYPOMA Gray, 1850 Pachypoma Gray, Figures of Molluscous Animals, Vol. 4, p. 88, 1850; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 244, 1888; Stewart, Proc. Acad. Nat. Sci., Phila., Vol. 78, p. 318 and footnotes, 1927. Type (by subsequent designation, Pilsbry, 1888), Trochus incequalis Martyn. Shell similar to that of Pomaidax, but umbilical area scarcely ribbed and operculum small, ejcternally very convex, white, and smooth, with a broad, central convexity and obscure, narrow side ribs. Astraea (Pachypoma) in ae quails (Martyn) Plate 31, Figures 4a, 4^-, 10 Trochus inxqualis Martyn, Universal Conchologist, Vol. 1, pi. 31, table, 1784, not of Gmelin, 1793. Trochus gibberosiis Pfeiffer, Ivrit. Regist. Mart. Chemn. Conch. Cab., p. 102, 1840, after Chemnitz, Vol. 10, p. 286, Vignette 23 A, B, 1788. Pachypoma gibberosum Chemnitz, Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 256, 1888. Astralium {Pachypoma) inequale Martyn, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 244, pi. 57, figs. 1, 5, 1888. Pachypoma inxquale Martyn, Williamson, Proc. IT. S. Nat. Mus., Vol. 15, p. 199, pi. 19, figs. 4, 5, oporcula, pi. 23, fig. 3, = variety depressum DaU, not pi. 23, figs. 1, 5, which represent undosa (Wood); Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 321, 1903. Asirsea {Pachypoma) precursor Dall, U. S. Geol. Surv., Prof. Paper 59, p. 93, pi. 6, figs. 5, 6, 1909, not Astralium {Lithopoma) precursor Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 384, pi. 18, fig. 8, 1892. Astrxa inequalis Martyn, Arnold and Hannibal, Proc. Amer. Phil. Soc, Vol. 52, p. 594, 1913. Astrxa inequale (Martyn), Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 43, 1916. Astrsea {Pachypoma) insequalis, variety padfica Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 356, August 30, 1919; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 165, pi. 108, figs. 3, 4, 1927. Pachypoma inxquale Martyn, Dall, U. S. Nat. Mus., Bull. 112, p. 172, 1921. Astrxa {Pachypoma) inxqualis Martyn, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 164, jil. 108, figs. 1, 2, 1927. Shell conic, imperforate, rather solid, with a chestnut brown cuticle, Ughter beneath; whorls 6-7, planulate above, sutures shghtly impressed, bordered below by a series of obHquely descending corrugations, which are cut mto granules by from one to five spiral furrows; periphery carinate, subspinose on the upper whorls, usually nearly smooth on body whorl; base nearly flat, concentrically Urate, the lirse more or less tuberculate, five or six m number, their mterstices regularly striate; aperture subtriangular, white withiir, the lower margin fluted; columella arcuate, broad, excavated at position of the umbilicus, and terminatmg in a tooth-like prommence below. Alt. 45, diam. 55-62 mill. ' (Pilsbry, 1888.) Miocene: Empire formation of Coos Bay, Oregon (DaU, as precursor). Pliocene: Fernando of Los Angeles, Fourth Street between Hill and Broadway (Moody) ; upper Pliocene at Bath-house Beach, S. D. S. N. H. loc. 101, Santa Barbara (coll. by U. S. Grant); Santa Barbara (Cooper). Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 821 Pliocene-Pleistocene: Coos conglomerate, Coos Bay, Oregon (Dall, 1909, Arnold and Hannibal, 1913). Pleistocene: Rare in upper San Pedro series of San Pedro (Arnold). Recent: Vancouver Island, British Columbia, to San Pedro and the Santa Barbara Islands, California (DaU, 1921). The variety pacifica Dall is the typical form of Martyn. The variety depressa Dall, 1909, is an individual variant. Astrcea precursor Dall is not specifically distinct from Martyn's species. The name precursor is preoccupied in Astrwa, but the Empire formation form is probably indistinguishable from Recent variants and hence is not in need of a name. Genus HOMALOPOMA Carpenter, 1864 Homalopoma Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 537, .588, 627, 1864. Leptonyx Carpenter, Proc. Calif. Acad. Nat. Sci., Vol. 3, pp. 175, 176, 1864; not Leptonyx Swainson, 1833, nor Gray, 1837, nor Lesson, 1842. Leptothyra Dall, Amer. Journ. Conch., Vol. 7, p. 130, 1871 (as of Carpenter MS.); Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 245, 1888; Dall, Bull. Mus. Comp. Zool., Harvard CoUege, Vol. 18, no. 29, "Blake Gastro- poda," p. 351, 1889; Cossmann, Ess. Paleo. Comp., Vol. 11, p. 127, 1918. Petropoma Gabb, Journ. Acad. Nat. Sci. Phila., Vol. 8, p. 281, 1877, fide Pilsbry, Nautilus, Vol. 7, p. 84, 1893. Type (by monotypy), Turbo sanguineus Linnaeus, Syst. Nat., Ed. 10, p. 763, 1758; Mediterranean and Adriatic seas; Recent. SheU small or minute, globose, depressed, solid, compact; umbilicate or imperforate, whorls 3-7, spirally sculptured, the last generally somewhat de flexed at the aperture; aperture subcircular, white and nacreous within; columella generally but not always bluntly denticulate near the base. Operculum subcircular, nearly fiat or concavo-convex, mside with a very thin corneous layer, slightly convex, with many gradually mcreasing whorls, the nucleus subcentral; outside calcareous, subspiral, with a shghtly convex concentric elevation or ridge around the margin, most prominent at its termination, the middle portion concave and more or less rugose. (Pilsbry, 1888.) Homalopoma Carpenter was never described but was used in 1864 with a species, H. sanguineum, which was attributed to Linnaeus. Although this species was probably not the shell which Carpenter had before him, it is necessary to consider it as the type by monotypy. Homalopomus Girard' does not preoccupy the name. Cantrainea Jeffries and Anadema Adams are apparently congeneric. According to Cossmann, the genus ranges from the Paleocene. The Recent species are in general warm and temperate water inhabitants and are abundant in the Pacific. Homalopoma carpenter! (Pilsbry) "Homalopoma sanguineum Lirmaus," Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 537, 588, 627, 1864, not of Linnaeus. "Leptonyx sanguineus Linn.," Carpenter, op. cit., p. 627, 1864; Keep, West Coast Shells, p. 87, fig. 73, 1888, 1892; not of Linnaeus. Leptothyra sanguinea Carpenter, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 85, 1868-9; Cooper, 7th Aim. Rept. Calif. St. Mineralogist, p. 245, 1888. Leptothyra carpenteri Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 247, pi. 39a, figs. 26 to 29, pi. 60, fig. 66 (oper- culum), 1888; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 199, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 323, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908; E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2 (p. 42), 1919; Dall, Bull. 112, U. S. Nat. Mus., p. 172, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 167, 1927. Type specimen: At the Academy of Natural Sciences, Philadelphia. Type locality: California; Recent. ' Proc. Acad. Nat. Sci. Phila. for 1856, p. 132. 822 San Diego Society of Natural History [Memoirs Shell small, globose, very solid, imperforate, spire conic, more or less depressed; suture mod- erately impressed; whorls 5, slightly convex, the last decidedly deflected toward the aperture, en- circled by about fifteen subequal spiral lirse, separated by interstices about as wide as the ridges; growth Unes usually strongly developed, causing the lirse to appear nodose or somewhat irregular and the interstices to appear pitted ; aperture oblique, pearly-white within, about half the length of the shell; columella arcuate, base obscurely uni- bi- or tri-dentate, color red, ashen, or purple. Alt. 8, diam. 8-9 mill.; dark form, alt. 5, diam. 5 mill. (After Pilsbry, 1888, alt.) Pliocene: Bath-house Beach, Santa Barbara (Berry). Pleistocene: Lower San Pedro series at Deadman Island and San Pedro; upper San Pedro series at San Pedro and Crawfish George's (Arnold) ; Pleistocene chiton bed at Point Firmin, Los Angeles County (E. P. and E. M. Chace) ; upper Pleistocene at San Quintin Bay, Lower California, Me.xico (Jordan) ; upper Pleistocene one and a half miles west southwest of Goleta, S. D. S. N. H. loc. 74, Santa Barbara County. Recent: Sitka Sound, Alaska, to San Diego, California (DaU, 1921). This species increases in size toward the northern Umit of its range. Recent speci- mens from Fort Bragg, northern California, are over 10 mm. in height, while those from San Pedro, Los Angeles County, average 5 or 6 mm. in height. Lower California speci- mens average about 3 mm. or less. The Goleta Pleistocene specimens measure up to 10 mm. in height. Leptothyra paucicostata has fewer, more prominent spiral ribs. Both it and car- penteri show considerable variation in color, carpenteri varying from a light cream color to a ruby red, the common color being a mottled olivaceous brown or gray. Mr. George Willett has collected Recent specimens from off Catalina Island which appear to be inter- grades. This species appears to be the coccineus of Troschel, 1879, not of Megerle,' 1816, the calif ornicus of von Martens, 1878, not of Philippi, 1849, and purpureus Carpenter, 1865, not Risso, 1826. Homalopoma bacula (Carpenter) LepUmyx bacula Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 652, 1864; Proc. Calif. Acad. Nat. Sci., Vol. 3, p. 177, 1864; Keep, West Coast SheUs, p. 87, 1888, 1892. Leptothyra bacula Carpenter, Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 85, 1868-9; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 248, pi. 39a, fig. 33, 1888; Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 245, 1888; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, p. 199, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 323, 1903; U. S. Geol. Surv., Bull. 321, p. 74, pi. 11, fig. 3, 1907; Berry, Nautilus, Vol. 22, p. 38, 1908; DaU, Bull. 112, U. S. Nat. Mus., p. 173, 1921; L S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 167, 1927. "Turbo paucicoslatus Dall," Sowerby, Thes. Conch., Vol. 5, Turbo, p. 229, pi. 13, fig. 172, 1886, not Leptothyra pauci- costata DaU, 1871. Type specimen: California State collection. No. 1,056, — at the LTniversity of Cali- fornia ? Type locality: Catalina Island, California; Recent, coll. by J. G. Cooper. Pliocene: Santa Barbara formation, upper Pliocene, at Bath-house Beach outcrop, Santa Barbara (Arnold; Berry). Pleistocene: Lower San Pedro series of Deadman Island, one specimen; also at Los Cerritos (Arnold, 1903). Recent: Puget Sound to San Martin Island, Lower California (Dall, 1921). H. bacula can be readily distinguished from carpenteri and paucicostatum by its much finer spiral sculpture. 1 Turbo coccineus Megerle, Mag. Ges. Nat. Fr. Berlin, Vol. 8, p. 9, 1816, = H. sanguineum (LinnEeus), 1758, fide Pilabry, 188S. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 823 Homalopoma paucicostatum (Dall) Leptothyra pavcicoslala Dall, Amer. Journ. Conch., Vol. 7, p. 131, pi. 15, fig. 10, 1871; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 10, p. 248, pi. 63, fig. 27, 1888; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 245, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 323, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908; DaU, Bull. 112, U. S. Nat. Mus., p. 173, 1921; E. K. Jordan, Proo. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Old- royd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 168, 1927. Type specimen: In the U. S. National Museum. Type locality: ^Monterey, California; Recent. Pliocene: Santa Barbara formation, upper Pliocene, at Bath-house Beach, Santa Barbara (Arnold, 1903; Berry) . Pleistocene: Lower San Pedro series of San Pedro, Los Angeles County, "two specimens" (Arnold, 1903). Recent: Monterey, California, to San Martin Island, Lower California, Mexico (Fred Baker MS.). Typical H. paucicostatum (Dall) is readily distinguished by its few, prominent, spiral ribs. However, a series of specimens obtained by Mr. George Willett from off Catalina Island seems to include specimens intermediate between paucicostatum and carpenteri, and it is possible that the difference between these two shells is varietal rather than specific. B. L. Clark has described "Leptothyra" danvillensis^ from the San Pablo formation, upper ^Miocene of middle California. This species resembles carpenteri (Pilsbrj^, but differs, according to Clark, "in that it is larger and the spire is higher; the base is flatter; the concentric ribbing is more regularly interspaced; the interspaces are wider; the sculpturing on the base of the body whorl is finer." Family TROCHIDAE Shell nacreous within, conical, pyramidal, subglobose, turbinate or helicoid; aperture entire, tetragonal or rounded; peristome generally not continuous. Operculum circular, thin, entirely corneous, formed of numerous gradually increasing whorls, nucleus central. (Pilsbry, in Tryon's Man. Conch. Ser. 1, Vol. 11, p. 5, 1889.) This large family differs from the Turbinidce in its thin, horny operculum, the latter family having a heavy calcareous operculum. Both families range back into the Paleo- zoic, possibly as far as the Ordovician, but the assignment of the more ancient genera to one or the other family is sometimes a matter of conjecture. The larger Trochidce are abundant in warm seas, mostly in shallow water, but some species are encountered at considerable depths. Some of the smaller members of the family, such as Margarites, s. s., are boreal in their habitat. A large number of generic and subgeneric group names have been proposed for this family. Only those which have been used for the Pacific coast Pliocene and Quaternary species, or appear applicable to them, are considered here. Genus TROCHUS Linnaeus, 1758 Trochus Linnseus, Syst. Nat., Ed. 10, p. 756, 1758; Montfort, Conch. Syst., Vol. 2, p. 178, 1810, type cited, "Trochus niloticus Linn."; Pilsbry, Man. Conch., Ser. 1, Vol. 11, p. 16, 1889; Cox, Paleontology of Zanzibar Protec- torate, p. 83, 1927. Pyramidea Swainson, Treat. Malac, p. 350, 1840. Rochia Gray, Guide MoU. Brit. Mus., p. 148, 1857, fide Pilsbry, 1889. Type (by subsequent designation, Thiele, 1924, fide Cox), Trochus maculatus Lin- naeus; Recent in Indian Ocean. ' UniT. Calif. Publ. Geol., Vol. 8, no. 22, p. 481, pi. 65, figs. 11, 12. Aug. 30, 1915. 824 San Diego Society of Natural History [Memoirs Shell large, thick, solid, the spire pyramidal or conical, periphery angulated or swollen, base flat or slightly convex, with a false umbilicus curvmg into the aperture ; outer and basal lips smooth within, the columella with a strong fold in the mnbilical region, ending in an elongate, obtuse tooth or a bluntly denticulated ridge below. This genus is at present largely distributed in the Old World. No species has been reported in the Neocene or Quaternary of the Pacific coast of North America. The restricted genus probably does not occur earlier than the Tertiary, although formerly Paleozoic and Mesozoic species were assigned to it for want of a better place to put them. Cossmann dates the genus from the Neogene. It is of interest to note that the type of this genus was not properly designated until 1924, all previous authors having designated Trochus niloticus Linnaeus, which was not described until the appearance of the 12th edition of the "Systema Naturse." Genus NORRISIA Bayle, 1880 Trochiscus Sowerby, Ann. Mag. Nat. Hist., \o\. 2, 1838, p. 96, type, T. norrisi Sby.; not Trochiscus V. Heyden, 1826, Arachnida; nor Trochisctis Held, 1837, Helices. Norrisia Bayle, Jour. Conchyl. for 1880, p. 241; Fischer, Man. Conchyl., p. 825, 1885. Type (by monotypy), Trochiscus norrisi Sowerby. Norrisia norrisi (Sowerby) Trochiscus norrisi Sowerby, Ann. Mag. Nat. Hist., N. S., Vol. 2, p. 96, 1838; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 665, 1864; Dall, Amer. Journ. Conch., Vol. 7, pi. 13, fig. 6, 1871, dentition; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 268, 1888. Turbo rolelliformis Jay, Cat. Shells, Ed. 3, p. 3, pi. 1, figs. 2, 3, 1859. Trochiscus convexus Carpenter, Ann. Mag. Nat. Hist., Vol. 15, p. 180, 1865. Norrisia norrisii Sowerby, Dall in Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 331, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 174, 1921; E. K. Jordan, BuU. So. Calif. Acad. Sci., Vol. 23, p. 150, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 172, 1927. Shell heavy, -wide, with low turbinate spire ; sculpture lacking except for light growth Imes and obscure spiral hnes ; aperture romided-quadrangular, pearly witliin, outer lip simple, thin, columella thickened at base and -nith a very obtuse tubercle ; umbilicus large, open. Large specimens measure 65 mm. in diameter, 45 mm. m axial height. Pleistocene: Pleistocene (?) at Santa Barbara (Cooper) ; lower Quaternary at Magdalena Bay, Lower Cali- fornia, Mexico (Jordan) ; upper San Pedro series at Deadman Island, Los Angeles County (Arnold) ; Pleistocene at Pacific Beach, San Diego (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Me.xico (Jordan, 1926). Recent: Monterey, California, to Cedros Island, Lower California. Genus HALISTYLUS DaU, 1889 Halistylus Dall, Proc. V. S. Nat. Mus., Vol. 12, p. 341, 1889, as subgenus of Canlharidus Montfort. Tijpe (by original designation and monotypy), H. columna Dall, op. cit., pi. 9, fig. 7, off Rio Janeiro and Rio Plata, Recent. "Shell small, cylindrical, holostomate, polychromatic; operculum multispiral, coriaceous; dental formula — . ; type: H. columna Dall. This group differs from Leiopyrga m its holostomate aperture and absence of spiral sculpture." (Dall.) Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 825 Halistylus pupoideus (Carpenter) Fenella piipoidca Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 6.56, 1864. Fenella suhpupoidea Tryon, Man. Conch., Ser. 1, Vol. 9, p. 394, pi. 60, fig. 77, 1887, new name for F. pupnidea Car- penter, 1864, not F. pupoides A. Adams, 1860. Halistylus subpupoideus Tryon, Ball, Bull. 112, U. S. Nat. Mus., p. 174, 1921; I. S. Oldroyd, Stanford Univ. Publ. Gaol., Vol. 2, Ft. 3, p. 173, 1927. Whorls about six, convex, closely spirally striate, thin, hght ohvaceous or brownish, with a series of chestnut spots under the suture; lip simple, sharp. Length, 6 mill. (Tryon.) Type specimen: In the Academy of Natural Sciences, Philadelphia, fide Oldroyd. Type locality: Monterey, California; Recent. Pleistocene: Pacific Beach, San Diego (specimens so labeled in Oldroyd Collection at Stanford University). Recent: Forrester Island, Alaska (Willett), to Panama Bay. Since Fenella pupoidea, described in three words and unfigured by Carpenter, is not a homonym of Fenella pupoides A. Adams, a Japanese shell, it is necessary to treat Tryon's name as a synonym, if the Iiiternational Rules are to be followed. Genus TEGULA Lesson, 1835 Tegula Lesson, lllust. Zoologie, liv. 17, pi. .51, 1835, "T. elegans"; Stoliczka, Mem. Geol. Surv. India, Pal. Indica, Cret. Gastrop., p. 364, 1867, type, "T. pellis-serpentis" ; Pilsbry, Man. Conch., Ser. 1, Vol. 11, p. 163, 1889; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 94, 1909. Type (by monotypy, fide Pilsbry, 1889), Tegula elegans Lesson, op. cit., = Trochus pellis-serpentis Wood, Index Test. Suppl., pi. 5, fig. 4, 1828, a Recent species ranging from the west coast of Central America to the Gulf of California. Shell Trochoid or Turbmate, heavy, smaller than Trochus; columella twisted and usually terminating below in one or more obtuse projections or denticles; callosity spreading over umbihcal region; umbihcus open or closed. When the genus Tegula is subdivided, it is sometimes difficult to place borderline species in the correct division because of the intergradation of closely related groups, although the extreme forms in each gi'oup are clearly distinguishable. There are no species of Tegula, sensu stricto, in the Pliocene and Quaternary faunas of California. Subgenus CHLOROSTOMA Swainson, 1840 Chlorostoma Swainson, Treat. Malac, p. 350, 1840; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 231, 1846; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 94, 1909. Type (by subsequent designation, Herrmannsen, 1846), Trochus argyrostomus Gmelin, Indo-Pacific, Recent. This subgenus differs from Tegiila, s. s., in the more ventricose whorls, which rapidly increase in size until the penultimate whorl is reached, the body whorl showing a less rapid increase in diameter. This feature of growth gives the penultimate whorl an appear- ance of disproportionate size and produces a dome-like spire. The sculpture is variable, consisting of spiral ribs, or sometimes of numerous protractive^ riblets, irregular or granulose. The surface color is often dark purple or dark gray. Beneath the surface the shell is pearly. The aperture is very oblique, the outer lip being smooth and pearly within, the columellar lip bearing one or more obtuse denticles. The umbilicus is open or closed, a callus wash covering the umbilical region. 1 That is, sloping to the left or forwards from the upper to the lower suture when the shell is Wewed with the spire upwards. Retractive is the opposite, sloping backwards. 826 San Diego Society of Natural History [Memoirs Chlorosioma differs from Calliostoma in its much heavier shell, dome-shaped spire, less uniform spiral sculpture, teeth or small projections on the columella or basal lip, and the dark or sombre and unattractive outer shell layer. Calliostoma, s. s., has an imperforate axis. This group of shells is characteristic of the Indo-Pacific and of both the eastern and western sides of the Pacific. It does not appear to be represented in the Atlantic. Section Chlorostoma, s. s. With axial or spiral riblets or both, outer shell layer usually dark purple or black. Omphalius differs in its much reduced or entirely obsolete sculpture and its rather smooth, light-colored outer shell layer. The retention here of Omphalius as a sub- division distinct from Chlorostoma is based upon the presence or absence of the spiral or the oblique axial sculpture and dark outer shell layer characteristic of species of typical Chlorostoma. The dividing line is not sharp and some species may fit as well in either section. Tegula (Chlorostoma) funebralis (A. Adams) Plate 32, Figures 28o, 286, 29 Chlorostoma funebrale A. Adams, Proc. Zool. Soc. London for 1854, p. 316; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 652, 1864; Gabb, Geo!. Surv. Calif., Pala;o., Vol. 2, p. 84, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 234, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. II, p. 170, pi. 28, figs. 42-44, 1889; Keep, West Coast SheUs, p. 84, fig. 71, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, pi. 21, fig. 7, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 325, 1903. Trochvs moestns Jonas, variety, Gould, U. S. Expl. Exped., Vol. 12, MoIIusca, p. 183, 1852, Atlas, pi. 13, fig. 214, 1856. Trochus funebralis A. Adams, Fischer, Kiener's Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 173, pi. 57, fig. 3, 1880. Tegula funebrale A. Adams, E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2 (p. 42), 1919. Tegula (Chlorostoma) funebrale A. Adams, Dall, U. S. Nat. Mus., Bull. 112, p. 174, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 173, pi. 98, figs. 8, 9, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Type specimen: In the Museum Cuming, collection now in the British Museum. Type locality: California, Recent. Pliocene: S. D. S. N. H. loc. 221, Canada de Aliso, loc. 222, Canada de las Encinas, middle or upper Pico of Ventura County (H. R. G.); loc. 225, between Santa Paula Creek and Timber Canyon, upper Pliocene, Ventura County (H. R. G.); upper and "lower" (= middle) Pico near Ventura (Water- fall). Pleistocene: Rare in lower San Pedro series at Deadman Island and San Pedro (Arnold); Saugus near Ventura (Waterfall) ; upper San Pedro series of Deadman Island, San Pedro, Los Cerritos, Long Beach, and Crawfish George's (Arnold); fossil chiton bed, Pt. Firmin, Los Angeles County (E. P. and E. M. Chace); Pleistocene of Barlow's Ranch, Ventura, and at Pacific Beach, San Diego (Arnold). Recent: Vancouver Island, British Columbia, to Cedros Island, Lower California, Mexico (Dall, 1921); sub- fossil in kitchen middens at Pismo Beach, also twelve miles west of Paso Robles, etc. This species is somewhat variable in sculptural development. "It is lustreless, purple or black, the apex usually eroded, orange-colored; the teeth of the columella are white; and there is never a yellowish streak at the base, as in the var. tincta [of T. gallina (Forbes)]. The whorls are spirally lirate, sometimes smooth except on the base, some- times strongly lirate above. The suture is margined below by an impressed line, and by elevated, foliaceous incremental lamellae. This last feature may almost always be detected, although sometimes but very slightly developed. Alt. 35, diam. 32; alt. 25, diam. 26 mill." (Pilsbry.) Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 827 This species was formerly used as food by the Indians of CaUfornia. The shells occur in abundance in a kitchen midden north of Pismo Beach, and they are not uncom- mon at an ancient Indian camp twelve miles west of Paso Robles, at an elevation of about 1200 feet and ten or more miles from the coast. At the latter deposit, which was first reported to be of Pleistocene age, many of the shells lack the upper portion of the spire or only the top of the spire remains, the Indians probably having broken the shells in this manner to extract the animal. Arrow heads occur with the shells at the latter locality. T. funebralis is distinguished from T. gallina by the lack of the axial riblets or stripes so common on the latter species. The puckered, finely pleated, or foliated growth lines just below the suture provide another distinguishing character. Tegula (Chlorostoma) funebralis (A. Adams) variety subaperta (Carpenter) Chlmostoma funebrale var. subaperlum Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 652, 1864; Dall, Proc. U. S. Nat. Mus., Vol. 15, p. 200, pi. 21, fig. 6, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 325, 1903. Tegnla (Chlorostoma) fvnebrale subaperlum Carpenter, Dall, U. S. Nat. Mus., BuU. 112, p. 174, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 3, p. 174, 1927. "With umbilical pit." (Carpenter.) Pleistocene: San Pedro (.Arnold). Recent: Neah Bay, Washington, to San Diego (Fred Baker). This variety is of very doubtful value. Tegula (Chlorostoma) dubiosa, new name Astralimn arnoldi Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 204, pi. 10, figs. 2a, 26, 1916; not Tegula amoldi Weaver, Washington Geol. Surv., Bull. 15, p. 71, pi. 6, fig. 62, 1912. Type specimen: In the Univer.sity of California collection. Type locality: SE }i, Sec. 27, T. 21 S, R. 14 E, Mount Diablo Base and Meridian, near Coalinga; lower Pliocene. Pliocene: At the type locality. This species is probably more closely related to Tegula funebralis (A. Adams) than to any other, but the spiral sculpture on dubiosa is so much coarser and more prominent that it may be specifically distinct. Unfortunately the specific name arnoldi was pre- occupied in Tegula, which makes a new name imperative. Tegula (Chlorostoma) gallina (Forbes) Plate 32, Figures 30, 31 Trochus [Monodonla) gallina Forbes, Proc. Zool. Soo. London, p. 271, pi. 11, figs. 8a-6, 1850. Trochus gallina Forbes, Fischer, in Kiener's Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 538, pi. Ill, fig. 1, 1880. Trochus [Monodonta) pyriformis Gould, Boston Journ. Nat. Hist., Vol. 6, p. 382, 1853. Chlorostoma gallina Forbes, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 652, 1864; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 169, pi. 20, fig. 5, pi. 28, figs. 52, 53, 1889; Keep, West Coast SheUs, p. 84, fig. 70, 1888, 1892; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 326, 1903. Tegula (Chlorostoma) gallina Forbes, Dall, U. S. Nat. Mus., Bull. 112, p. 174, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 174, 1927. Tegula gallina Forbes, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, no. 7, p. 247, 1926. Type specimen: Presumably in the British Museum. Type localities: Of gallina, "probably from the Mazatlan coast" (Forbes); of pyri- formis, San Diego, California. 828 San Diego Society of Natural History [Memoirs Pliocene: S. D. S. N. H. loo. 207, basal Pico Pliocene of Elsmere Canyon; loc. 216, basal Pico east of Fernando Pass; loc. 214, middle Pico of Fernando Pass, Los Angeles County, aU uncommon (H. R. G.). Pleistocene: "Rare in the upper San Pedro series of San Pedro, Crawfish George's, and Deadman Island," Los Angeles County; Pleistocene at Pacific Beach, San Diego County (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Francisco, California, to the Gulf of California, Me.xico. This large, heavy-shelled species is characterized by the oblique axial riblets, which consist of closely spaced, sometimes irregular, superficial folds on the surface of the shell. The interspaces between these riblets are often lighter colored, giving a striped effect. However, this sculpture varies from strong to nearly obsolete and the riblets are sometimes granulose. The variety with an open umbilicus Dall has named umbilicata^ The presence or absence of an umbilicus in Tegula is frequently a function of the amount of callus depos- ited in the umbilical region, the umbilicus being structurally present even in the imper- forate individuals, although covered over basally by the deposit of shelly substance. The Recent range of the variation umbilicaia is coincident with that of the typical form, which helps to confirm the opinion that umbilicata is no more than an individual variation. Until more data on the actual occurrence of living specimens is available, we consider the "variety" a cabinet name. The variety with obsolete sculpture and a yellowish streak on the base just below the columellar teeth is known as variety tincta Hemphill in Pilsbry, 1889. Still another variety, characterized by strong spiral sculpture, has been named multifilosa by Stearns. ^ The geographic range of this form falls within that of the typical form. Tegula (? Chlorostoma) lahondaensis (Arnold) Chlorostoma stanloni Dall, var. lahondaensis Arnold, Proc. U. S. Nat. Mus., Vol. 34, p. 388, pi. 36, fig. 2, August, 1908. Broad, low spired, with few rounded ribs; attaining an altitude of 25 mm. Type specimen: "L. S. J. U., No. 1,079." Type locality: Along Pescadero Creek, three miles south of La Honda, San Mateo County; Pliocene (Arnold). Pliocene: Lower Pliocene (lower Purisima formation) on Pescadero Creek, just above mouth of Jones Gulch, three miles due south of La Honda, San Mateo County, California (Arnold). Since Arnold described variety lahondaensis before Dall proposed in print the name stantoni, Arnold's form will have to be considered the typical form, lahondaensis, and Dall's Coos Bay form the variety or subspecies. Neither form is a typical Chlorostoma. Tegula (? Chlorostoma) lahondaensis (Arnold) variety stantoni Dall Tegula (Chlorostoma) stantoni DaU, U. S. Geol. Surv., Prof. Paper 59, p. 95, pi. 2, figs. 10, 11, April, 1909. Type specimen: In the U. S. National Museum, No. 107,777. Type locality: "Miocene of Coos Bay, Oregon" (Dall). Miocene: At the type locality, upper Miocene. Pliocene: "Lower Purisima formation, Santa Cruz County, California, Arnold" (Dall). 1 Proc. U. S. Nat. Mus., Vol. 56, p. 359. 1919, type locality, San Quintin Bay, Lower California. » Proc. U. S. Nat. Mus., Vol. 16. p. 351, pi. 50, figs. 8, 9, 1893. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 829 Dall figures a rather low-spired shell, with few, widely spaced, prominent ribs. The apertural characters are obscured by matrix. This shell is more elevated and has more prominent spiral sculpture than lahondaensis. It is far from being a typical Chlorostoma and may not be a Tegula. Tegiila (? Chlorostoma) ligulata (Menke) Trochus ligulatus Menke, Zeitschr. f. Malak., for 1850, p. 173; Fischer, in Kiener's Sp^c. Gen. Icon. Coq. Viv., VoL 12, p. 382, pi. 115, fig. 5, 1880. Omphalius ligulahts Menke, Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 235, 1857. Trochus luridus Nuttall, MS., Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 233, 1857. "Omphalius fuscescens Philippi," Carpenter, Brit. A!;sn. Adv. Sci., Rept. for 1863, p. 652, 1864, not of Philippi , Abbild. Beschreib., Vol. 1, Trochus, pi. 3, fig. 8, 1844; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 255, 1888; Keep, West Coast Shells, p. 82, fig. 68, 1888, 1892. Chlorostoma (Omphalius) viridulum Gmelin, var. ligulatum, Menke, Pilsbry, Tryon's Man. Conch. Ser. 1, Vol. 11, p. 177, pi. 29, figs. 58-60, 1889; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, 1892. Omphalius ligulatus Menke, Dall, Bull. 112, U. S. Nat. Mus., p. 175, 1921. Tegula ligulata Menke, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 150, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 247, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 181, 1927. Type locality: Mazatlan, Mexico, fide Oldroyd. Pleistocene: "Rare in lower San Pedro series of Deadman Island and San Pedro, Los Angeles County (Arnold) ; lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan) ; upper San Pedro series of Los Cerritos and Crawfish George's, common (Arnold); rare in upper San Pedro of Deadman Island and San Pedro, Los Angeles County (Arnold); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to Acapulco, Mexico (Dall). This species is extremely variable. The shell is usually turbinate, the whorls quite ventricose and sculptured with spiral riblets, which are in most cases granulose. The umbilicus is wide open and the columellar lip has two or three small denticles. The basal Up bears a few lirse which extend back into the aperture. The whorls and aperture are smaller than in T. viridula (Gmelin), and the columella lacks the green tinge. This species also lacks the broad radiating stripes of T. reticulata (Wood) and T. viridula. Section Omphalius Philippi, 1847 Omphalius Philippi, Zeitschrift f. Malak., for 1847, p. 21; Herrmannsen, Indicis Gen. Malac, Vol. 2, p. 146, Sept. 8, 1847. Type (by subsequent designation, Herrmannsen, 1847), Trochus rusticus Gmelin, Japan; Recent. The intermingling of the characters that might be used for sectional differentiation among the species of Chlorostoma makes it difficult to define Omphalius in a manner that will not be obviously artificial. The name could be discarded without any loss to sys- tematics, but it is utilized here for a few species that are like the type or lack some of the more obvious characters of Chlorostoma, s. s. For example, Tegula brunnea (Philippi), of California, is similar to T. rustica (Gmelin), of Japan, at least to the variety of the latter which has a smooth, light yellowish-brown outer shell surface. The spiral sculpture and (in brunnea and the smooth rustica) the oblique axial riblets are wanting. The presence or absence of an open umbilicus is entirely unreliable for systematic arrange- ment in the group of which rustica is an example. The widely open, funnel-shaped umbiUcus of species such as T. montereyi, however, seems to be significant, but it has a very different appearance when coupled with a flat base and angulated body whorl. 830 San Diego Society of Natural History [Memoirs Tegula (Chlorostoma) brunnea (Philippi) Trochus bninncvx Philippi, Zeitschr. f. Malak., for 1848, p. 189; ? Lischke, Japan. Meeres-Conchyl., Vol. 1, p. 99, 1869; Fischer, in Iviener's Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 365, pi. 112, fig. 1, 1880. Chlorostoma briinneum Philippi, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 652, 1864; Gabb, Geol. Surv. Calif., Palso., Vol. 2, p. 84, 1868-9; Cooper, 7th .\nn. Rept. Calif. St. Mineralogist, p. 234, 1888; Pilsbrj-, Tryon's Man. Conch., Ser. I, Vol. 11, p. 170, pi. 27, figs. 36-38, 1889; Keep, West Coast Shells, p. 83, fig. 69, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, pi. 21, fig. 8, 1892; .Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 324, 1903; Dall, Bull. 112, U. S. Nat. Mus., p. 174, 1921. Teffula brunnea Philippi, E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2 (p. 42), 1919. Tegula (Chlorosloma) brunnea Philippi, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 176, 1927. Shell imperforate, conical, solid; color russet-yellow, brown, orange, or deep crimson; spire conic; sutures deeply impressed; whorls about seven, convex, smooth, with light, oblique striae, the last whorl sometimes indistinctly undulated or plicate l^elow the suture; l^ase depressed, deeply concave in the center ; aperture veiy oblique ; columella one or two toothed near the Ijase ; umbilical callus white; place of the umbilicus deeply excavated. Alt. 32, diam. 36; alt. 38, cham. 35 mill. (After Pilsbry, alt.) Pleistocene: "Pliocene" of Deadman Island, rare; upper San Pedro series of Deadman Island and Crawfish George's, Los Angeles County (Arnold); Pleistocene at the chiton bed, Pt. Firmin, Los Angeles County (E. P. and E. M. Chace). Recent: Mendocino County to the Santa Barbara Islands, California (Dall). This species is very close to T. rustica (Gmelin) of Japan, the type of Omphalius. Lischke reported it on the coast of Japan, but the form he reported may have been rustica. It certainly belongs to Omphalius, if that section is of any value. Tegula (Chlorostoma) aureotincta (Forbes) Trochus (Monodonta) aureo-tinclus Forbes, Proc. Zool. Soc. London for 1850, p. 271, pi. 11, fig. 7. Chlorostoma aureotinctum Forbes, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, pp. 652, 667, 1864; Cooper, 7th Aim. Rept. Calif. St. Mineralogist, p. 234, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 172, pi. 27, figs. 31-33, 1889; Keep, West Coast Shells, p. 84, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 324, 1903. Trochus aureo-tinctus Forbes, Fischer, in Kiener's Spec. Gen. Icon. Coq. Viv., Vol. 11, p. 94, pi. 31, fig. 1, 1873. Omphalius aureotinctus Forbes, Dall, BuU. 112, U. S. Nat. Mus., p. 175, 1921. Tegula aureotincta Forbes, E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 150, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Tegula (Oiiiphalius) aureotincta Forbes, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 180, 1927. Pleistocene: Santa Barbara (Cooper); lower Quaternary at Magdalena Bay, Lower California, Mexico (Jor- dan); upper San Pedro series at San Pedro, rare (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent:' SantSL Barbara Islands, California, to Magdalena Bay, Lower California, Mexico (Dall). This species is characterized by its turbinate shape, its few, low, rounded spiral ribs on the base, its undulated and nodose whorls, and its open umbilicus tinted with orange. It is beautifully figured in color by Forbes. Tegula (Chlorostoma) hemphilli T. S. Oldroyd Tegula hemphilli T. S. Oldroyd, Nautilus, Vol. 34, no. 4, p. 115, pi. 5, figs. 11, 11a, April, 1921. Type specimen: At the University of California. Type locality: Pacific Beach, San Diego; Pleistocene. Pleistocene: Pacific Beach, San Diego (Oldroyd). This shell has low undulations or nodosities and fine spiral threads, which are somewhat granulose. It is a rather depressed form, with the base flatly convex and a wide, open umbilicus. There are two small denticles on the columellar lip. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 831 Tegula {? Chlorostoma) pulcella Nomland Tegrda (Chlorosloma) pulcella Nomland, Univ. Calif. Publ. Geol., Vol. 10, no. 14, p. 23.5, pi. 12, figs. .3, 3a, 1917. Type specimen: At the University of California, type no. 11,101. Type locality: Coalinga district, California; upper middle Pliocene. Pliocene: "Pecten coalingensis zone," u]jper Etchegoin of the Coalinga region, California. This species is characterized by its conical, flat-sided shape, with a flat base, open umbilicus, and low, rounded axial riblets. It is certainly far from typical Chlorostoma or Omphalius and may belong in another group. Its shape suggests possible relationship with T. jnontereyi (Fischer in Kiener). It can hardly belong to Promartynia Dall.' Incertae Sedis Tegula montereyi (Fischer in Kiener) "Omphalius pfeifferi Philippi," Carpenter, Proc. Zool. Soc. London, for 1856, p. 20-t, 1856, not Trochus pfeifferi Philippi, Zeit.schr. f. Malak., for 1846, p. 104. "Chlorostoyna pfeifferi Philippi," Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 652, 1864; Gabb, Geol. Surv. Calif., Pateo., Vol. 2, p. 84, 1868-9; Cooper, 7th Ann. Kept. Calif. St. Mineralogist, p. 234, 1888; Keep, West Coast SheUs, p. 83, 1888, 1892. Trochus montereyi Fischer in Kiener, Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 104, pi. 33, figs. 1, la, 1880. Chlorostoma mcmtereyensis Kiener, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 200, 1892. Chlorosloma montereyi Kiener, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 326, pi. 10, fig. 19, 1903. Shell evenly conical, of five or sL\ flat-sided whorls; base of body whorl flat; umbilicus open, funnel-Uke, with a bordering spiral rib ; sculpture much reduced, consisting essentially of fine spiral threadlets crossed by faint gro^^•th lines. Measurements of average mature specimen, diameter at base 35 mm., slant height 35 mm. Type locality: California coast; Monterey (Fischer in Iviener). Pleistocene: "Pliocene of Deadman Island"; lower San Pedro series of Deadman Island; upper San Pedro series of Deadman Island, Crawfish George's, and San Pedro, Los Angeles County; Pleistocene of Pacific Beach, San Diego County (Arnold). Recent: Paulinas Bay, middle California, to the Santa Barbara Islands (Dall). This species is very different from the other California shells assigned to Chlorostoma or Omphalius. It appears to belong in a different subgenus. Phorcus Risso- seems to have a differently shaped body whorl. Several species of Tegula, s. L, occur in the earlier Tertiary of the Pacific coast. Among them are Tegula danvilletisis Clark and T. nashi Clark from the San Pablo formation of middle California, T. thea Nomland and T. varislriata Nomland from the Santa Margarita upper Miocene at several localities, and T. arnoldi Weaver from the Blakeley formation, lower Miocene of Washington. Genus CALLIOSTOMA Swainson, 1840 Calliostoma Swainson, Treat. Malac, pp. 218, 351, 1840; list includes "C. conula Mart."; Herrmannsen, Indicis Gen. Malac, Vol. 1, p. 154, 1846; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 332, 1889; Cossmann, Ess. Paleo. Comp., Vol. 11, p. 288, 1918. Ziziphinus Gray, Syn. Cont. Brit. Mus., 1840, type T. zizyphinus Linnaeus. Type (by subsequent designation, Herrmannsen, 1846), Trochus conulus Linnseus (= "Calliostoma conula Mart." of Swainson), Mediterranean Sea; Recent. ^ U. S. Geol. Survey, Prof. Paper 59, p. 94, 1909, type by original designation, P. puUigo (Martyn). 2 Hist. Nat. Eur. M^rid., Vol. 4, p. 133, 1826; type, Trochus richardi Payraudeau, = Phorcus margaritaceus Risso, fide Bucquoy, Daut- zenberg, and Dollfus, Moll. Mar. Roussillon, Vol. 2. faso. 10, p. 399, 1885. 832 San Diego Society or Natural History [Memoirs Imperforate; spire elevated, acute; aperture broader than high, transversely ovate, hardly sinuated at the base, and slightly oblique; shells always smooth, and often polished. (Swainson.) Geologic range: Eocene to Recent (Cossmann). Distribution: All seas. Dall' has suggested that Leiotrochus Conrad may be used for the umbilicated Calliostomas. Calliostoma annulatum (Martyn) Trochus annulalus Martyn, Univ. Conch., table 1, pi. 33, 1784; Fischer, in ICiener's Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 74, pi. 16, fig. 3, 1880. Trochus virgineus Chemnitz, Neues Syst. Conch. Cab., Vol. 10, p. 289, pi. 165, figs. 1581-2, 1788. Zizyphinus annulaiiis Martyn, A. Adams, Proc. Zool. Soc. London for 1851, p. 164. Calliostoma annulatum Martyn, Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 652, 1864; Gabb, Geol. Surv. Calif., PaliEo., Vol. 2, p. 83, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 231, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 363, pi. 67, fig. 43, 1889; Keep, West Coast Shells, p. 79, fig. 64, 1888, 1892; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, pi. 22, fig. 2, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 329, 1903; Dall, Biill. 112, U. S. Nat. Mus., p. 176, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 184, pi. 97, figs. 1, 3, 1927. Calliostoma annulatum Martyn, n. var. ? Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pliocene: San Diego well, southwest corner of Balboa Park, San Diego, California (DaU) ; Pico near Ventura, as new variety (Waterfall). Pleistocene: S. D. S. N. H. loc. 233, "Saugus" formation north of Arroyo Santa Rosa, Ventura County, frag- ments (Grant, coll.); quite rare in upper San Pedro series of San Pedro (Arnold); Pleistocene, San Pedro to San Diego (Cooper). Recent: Forrester Island, Alaska, to Catalina Island, California (Dall). This very handsome species has granular spiral riblets and a delicate lavender color band just above and adjacent to the lower suture of each whorl. The basal periphery of the body whorl is angular. Large specimens have a diameter of 25 mm. and a slant- height of nearly 30 mm. C variegatum Carpenter has a somewhat inflated body whorl, without the angle at the base, and the coloration is less brilliant. Calliostoma kerri Arnold Calliostoma kerri Arnold, U. S. Geol. Surv., Bull. 396, p. 84, pi. 27, fig. 6, January 15, 1910; Nomland, Univ. Calif. Publ. Geol., Vol. 10, no. 14, p. 220, 1917. Type specimen: In the U. S. National Museum, No. 165,500. Type locality: Immediately east of Henry Spring, four miles south of Coalinga, California; Etchegoin Pliocene. Pliocene: Etchegoin of south central part of Kettleman Hills; east of Zapato Creek; four miles south of Coahnga, all Coalinga district, west side of San Joaquin basin (Arnold); Peden coalingensis zone, "common," Coalinga district (Nomland). Arnold distinguished this species from the Recent Calliostoma variegatum Carpenter- "by its relatively broader outline, more nearly flat base, less prominently nodose revolving sculpture, and smaller and smoother concentric ribs on the base; also by the greater inequality between the outer and inner basal ribs on the one hand and the intermediate ones on the other." 1 U. S. Geol. Surv., Prof. Paper 59, p. 95, 1909. 2 Proc. Acad. Nat. Sci. Phila. for 186S, p. 61; see Proc. U. S. Nat. Mus., Vol. 24, p. 552, pi. 39, fig. 10, 1902; range Puget Sound to Cedros Island, Lower California. Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 833 Calliostoma canaliculatum (Martyn) Plate 32, Figure 23 Trochus canalictdatus Martyn, Univ. Conch., table 1, pi. 32, 1784. Trochus doliarius Chemnitz, Neues Syst. Conch. Cab., Vol. 10, p. 288, pi. 165, figs. 1579, 1580, 1788; Fischer, in Iviener's Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 71, pi. 16, fig. 1, 1880. Calliostoma canaliculalum Martyn, Cooper, Brit. Assn. Adv. Sci., Rept. for 1863, p. 652, 1864; Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, p. 83, 1868-9; Cooper, 7th .'^n. Rept. Calif. St. Mineralogist, p. 231, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 361, pi. 67, fig. 49, Vol. 10, pi. 41, fig. 34, 1889; Keep, West Coast Shells, p. 80, fig. 65, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, pi. 22, fig. 6, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 329, 1903; Berry, Nautilus, Vol. 22, p. 38, 1908; Dall, Bull. 112, U. S. Nat. Mus., p. 176, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 247, 1926; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 3, p. 184, pi. 97, figs. 4, 6, 1927. Pliocene: Pacific Beach, San Diego (Arnold); Bath-house Beach outcrop, Santa Barbara formation, upper Pliocene, Santa Barbara (Berry). Pleistocene: "Pliocene" of Deadman Island, rare, and rare in lower San Pedro series of Deadman Island and San Pedro; common in upper San Pedro series of Deadman Island, San Pedro, Los Cerritos, and Crawfish George's, all Los Angeles County (Arnold); Pleistocene at Spanish Bight (.Arnold; Mrs. K. Stephens MS.); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Sitka, Alaska, to San Diego, California (Dall). This species is readily distinguished by its large size, prominent spiral riblets, and flattened base. The ribs are very evenly spaced, those on the earlier whorls being few in number, but they are augmented toward the body whorl by the gradually increasing prominence of the intercalated riblets. The base of the body whorl is angulated. Full- grown individuals attain a diameter of 25 mm. and an axial height of 25 mm. C. costatum (Martyn) has a much stronger shell, a rounded body whorl, and is smaller. The variety nebulosuyn Dall takes the place of parvum Williamson, the latter name being preoccupied by Da Costa. It is probably of no consequence and should be synonymized along with the supposed variety transliratum Dall. Calliostoma costatum (Martyn) Plate 32, Figure 25 Trochus costatus Martyn, LTniv. Conch., table 1, pi. 34, 1784, not Trochus costatus Gmelin, 1788. Trochus filosus Wood, Index Test., Suppl., pi. 5, fig. 23, 1828; Fischer, in Kiener's Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 199, pi. 64, figs. 5, 1880. ? Trochus 7nodestvs Middendorff, Beitr. Mai. Rossica, Vol. 2, p. 85, pi. 10, figs. 16-18, 1847. Trochus ligatus Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 91, March, 1849; U. S. Expl. Exped., Vol. 12, Mol- lusca, p. 185, 1852, Atlas, pi. 12, figs. 207a-6, 1856. Troclius caslanetis Nuttall MS., Forbes, Proc. Zool. Soc. London for 18.50, p. 271, pi. 11, fig. 9. Calliostoma costatum. Martyn, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 652, 1864; Gabb, Geol. Surv. Calif., Palseo., Vol. 2, p. 83, 1868-9; Cooper, 7th Aim. Rept. Calif. St. Mineralogist, p. 231, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 362, 1889; Keep, West Coast SheUs, p. 81, fig. 66, 1888, 1892; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, p. 201, pi. 22, fig. 1, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 330, 1903; Dall, BuU. 112, U. S. Nat. Mus., p. 175, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 183, pi. 97, figs. 8, 10, 1927. Calliostoma etchegoinensis Nomland, Univ. Calif. Publ. Geol., Vol. 9, no. 6, p. 85, pi. 7, fig. 3, 1916. Calliostoma costatum variety aeruleuni Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 359, 1919. Calliostoma costatum variety pictum Dall, op. cit., p. 359, 1919. Calliostoma costatum cseruleuvi Dall, U. S. Nat. Mus., Bull. 112, p. 175, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 183, 1927. Calliostoma costatum pidum Dall, U. S. Nat. Mus., BuU. 112, p. 176, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, 1927. Smaller, heavier shelled, with less prominent spiral sculpture and more rounded body whorl than C. canaliculatum. 834 San Diego Society of Natural History [Memoirs Type locality: "King Georges Sound." (Martyn.) Pliocene: Etchegoin formation north of Oilfields, Coalinga region, California (Nomland); San Fernando, Los Angeles County (Cooper). Pleistocene: Lower San Pedro series of Deadman Island and San Pedro, rare; upper San Pedro series of Crawfish George's, Los Cerritos, and San Pedro; Pleistocene at Pacific Beach, San Diego (Arnold). Recent: Sitka, Alaska, to San Diego, California (DaU). This species is similar to a large Margarites. Nomland's etchegoinense is the young of Martyn's species, the angulated body whorl being a juvenile character. Recent speci- mens have slightly granulose ribs, the granulations becoming emphasized through weathering. Shells with the apex and part of the whorls in front of the suture colored with bands of mazarin blue when fresh were named variety cceruleum by Dall, and those with alternating light and dark patches or clouds of color were named variety pidum by the same author. Both names apply to individual variants and are entirely unnecessary. Calliostoma augustinense Hertlein Calliostoma augitstinensis Hertlein, Journ. Paleo., Vol. 2, p. 154, pi. 25, figs. 4, 5, June, 1928. Shell rather low, conic, imperforate, fairly thin; about 4 rounded whorls present; body whorl broadly rounded below; surface with numerous, fine, even, spiral, rather flat-topped ribs, which are separated by smaller fine lines. Height, 21 mm.; length, 29 mm. Type specimen: No. 4,146, California Academy of Sciences. Type locality: San Augustine Canyon, Santa Rosa Island, California; lower Miocene. Miocene: Vaqueros formation at the type locality. Calliostoma coalingense Arnold Calliostoma coalingensis Arnold, U. S. Geol. Surv., Bull. 396, p. 83, pi. 27, fig. 7, January 15, 1910; Bull. 398, pi. 49, fig. 7, 1910; Nomland, Univ. Calif. Publ. Geol., Vol. 10, table opp. p. 230, 1910. Type specimen: In the U. S. National Museum, No. 165,499. Type locality: Coalinga district, California; Pliocene. Pliocene: Pecten coalingensis horizon near top of Etchegoin formation, near Zapato Creek; also four miles south of Coalinga, west side San Joaquin basin (Arnold); Etchegoin of Coalinga, common in "Chione elsmerensis," "Turritella nova" and "Pecten coalingensis" zones (Nomland). Arnold differentiated this species from Calliostoma costatum (Martyn) by "its rela- tively lower spire, more convex and angulated whorls, narrower, more numerous, more markedly unequal, and often slightly nodose revolving ribs." This form should, perhaps, be considered a variety of costatum. Calliostoma cammani Dall Calliostoma cammani Dall, U. S. Geol. Surv., Prof. Paper 59, pp. 18, 96, pi. 2, figs. 8, 9, April, 1909; Arnold and Hannibal, Proc. Amer. Philos. Soc, Vol. 52, p. 590, 1913. Type specimen: In the U. S. National Museum, No. 107,776. Type locality: Coos Bay, Oregon; Miocene. Miocene: Coos Bay, Oregon (Dall); "shaly sandstone, beach between submerged jetty and Fossil Rock, three miles south of Empire, Coos Bay, Oregon" (Arnold and Hannibal); upper Miocene. DaU states: "This strongly spirally sculptured species recalls the more acute and elevated C. virginicum of Conrad, from the Virginia Miocene. In its sculpture it re- sembles Chlorostoma stantoni Dall, of the Empire formation of Coos Bay, but can readily be discriminated." Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 835 CalUostoma gemmulatum Carpenter Plate 32, Figure 21 Callinstoma geinmidatum Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 6.53, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 215, 1864; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 231, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 371, pi. 67, fig. 54, 1889; Keep, West Coast Shells, p. 81, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 201, pi. 22, fig. 3, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 330, 1903; DaU, Bull. 112, U. S. Nat. Mus., p. 176, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 189, 1927. Type specimen: In the U. S. National Museum. Type locality: California. Pliocene: Packard's Hill, Santa Barbara (Arnold). Pleistocene: L'pper San Pedro series of San Pedro, Los Cerritos, and Crawfish George's, Los Angeles County; Pleistocene at Spanish Bight (Arnold ) ; Pleistocene terrace a half mile south of Sea Cliff on Southern Pacific R. R., eight miles north of Ventura (coll. by Parish and Smith). Recent: San Pedro, California, to Gulf of California. This species is a rather high-spired form, with a few prominent, granular spiral ribs, two on the early whorls, but the number increasing to four or five on the body whorl by the increase in prominence of intercalated riblets. The upper part of each whorl is slopingly, somewhat concavely tabulated. Average mature individuals measure 24 mm. in axial length and 20 mm. in diameter at the base. This species is heavier shelled, with fewer, more prominent spiral ribs than Cal- Uostoma annulatum (Martyn). Calliostoma eximium (Reeve) Trochus eximius Reeve, Proc. Zool. Soc. London for 1842, p. 185; Conch. Syst., Vol. 2, p. 165, pi. 208, fig. 12, 1842; Fischer, in Kiener's Spec. Gen. Icon. Coq. Viv., Vol. 12, p. 196, pi. 64, fig. 1, 1880. Trochus versicolor Menke, Zeitschr. f. Malak., p. 172, 1850; Carpenter, Cat. Reigen. Coll. Mazatlan Moll. Brit. Mus., p. 231, 18.57. ? Zizyphinus californicus A. Adams, Proc. Zool. Soc. London for 1851, p. 168. Zizyphinus eximius Reeve, Conch. Icon., Vol. 14, sp. 25, pi. 4, figs. '25a-b, 1863. Calliostoma eximium Reeve, Pilsbry, Tryon's Man. Conch., Vol. 11, p. 366, pi. 65, figs. 84-86, 1889; also figured in Vol. 10, pi. 41, fig. 28; Dall, U. S. Nat. Mus., Bull. 112, p. 176, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 1.50, 1924; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 188, 1927. Type locality: Panama; Recent. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan). Recent: Santa Catalina Island, California, to Mazatlan, Mexico (Dall). This species is readily recognizable by the carinated whorls, which are concave above and straight and approximately vertical below. There are very low spiral cords on the base of the body whorl and inconspicuous spiral threads on the upper portion of the shell. Calliostoma hannibali Hertlein and Jordan Calliostoma hannibali Hertlein and Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 626, pi. 21, figs. 8, 9, Sept. 2, 1927. SheU small, rather tliin, conical, imperforate; tip of spire missing, four and one-half whorls present in type specimen; whorls sloping and broadly rounded to near periphery where a small angular shoulder is present; from shoulder, whorls slope abruptly to base; body whorl rounded at periphery; near base whorls ornamented by a raised spiral line; on next to last whorl a raised spiral Une occurs midway between suture and angular shoulder; whorls ornamented by numerous fine spiral lines which are strongest on base of body whorl. Height approximately 20. .5 mm.; width of body whorl 12.5 mm.; apical angle approximately 8.3°. (Hertlein and Jordan.) 836 San Diego Society of Natural History [ Memoirs Type specimen: In the Stanford University collection. Type locality: In Arroyo San Ignacio, southwest of San Ignacio, Lower California, Mexico, Isidro formation; lower Miocene. Miocene: At the type locality. The type of this species is not very edifying but it might be related to C. eximium (Reeve). Calliostoma tricolor Gabb Calliosloma tricolor Gabb, Proc. Calif. Acad. Nat. Sci., Vol. 3, p. 186, 1865; Geol. Surv. Calif., Palseo., Vol. 2, p. 17, 1866, pi. 3, fig. 28, 1868-9; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 231, 1888; Pilsbry, Tryon's Man. Conch., Vol. 11, p. 370, pi. 67, fig. 52, 1889; Keep, West Coast Shells, p. 82, 1888, 1892; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, pi. 19, fig. 8, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 331, 1903; Dall, BuU. 112, U. S. Nat. Mus., p. 176, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 150, 1924; Proc. CaUf. Acad. Sci., Ser. 4, Vol. 15, p. 247, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 188, 1927. Like C. eximium (Reeve), but not concave above the middle of the whorls, and the carina not so pronounced. Type specimen: Location not known, fide Stewart, Proc. Acad. Nat. Sci. Phila., Vol. 78, p. 291, 1927. Type locality: San Pedro, California. Pleistocene: "Pliocene" of Deadman Island, rare; lower San Pedro series at San Pedro (Arnold); lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan, 1924); upper San Pedro series of Crawfish George's, San Pedro, and Los Cerritos, Los Angeles County; Pleistocene at Spanish Bight (Arnold); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: Santa Cruz to San Diego, California (Dall). This species is very closely related to C eximium. Some specimens have a slight depression in the umbilical region. Calliostoma gloriosum Dall CaUiostoma gloriosum Dall, Amer. Journ. Conch., Vol. 7, p. 127, Nov. 2, 1871; PUsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 368, pi. 67, fig. 70, 1889; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, p. 201, pi. 22, fig. 5, 1892; DaU, U. S. Nat. Mus., Bull. 112, p. 176, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 150, 1924; Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 247, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 187, 1927. Type specimen: In the U. S. National Museum. Type locality: Soquel, north side of Monterey Bay, California. Pleistocene: In the lower Quaternary at Magdalena Bay (Jordan, 1924) and in the upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan, 1926). Recent: "Twelve miles south of the Golden Gate and thence to San Diego, California" (Dall, 1921). This species is somewhat like C. tricolor Gabb but lacks the carina, and the fine spiral threads are a little more conspicuous and granulose. Calliostoma supragranosum Carpenter Calliostoma formosum Carpenter, Proc. Calif. Acad. Sci., Vol. 3, p. 156, 1865, not T. formosus Forbes, 1847. Calliostoma supragranosum Carpenter, op. cit., p. 214, 1865; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 369, pi. 67, fig. 71, 1889; E. P. and E. M. Chace, Lorquinia, Vol. 2, No. 6, p. 2 (p. 42), 1919; Dall, Bull. 112, U. S. Nat. Mus., p. 176, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 189, 1927. VoLmiE I ] Pliocene and Pleistocene Mollxjsca of California 837 Type locality: San Pedro, California; Recent. Pleistocene: Pleistocene chiton bed at Point Firmin, Los Angeles County (Chace). Recent: San Pedro to San Diego, California (Dall). This is a very small species (alt. 5-7^9 mm., diam. 5J^-73^ mm.), with fine spiral riblets and rows of granules. It is a shallow-water form. Calliostoma splendens Carpenter Calliostoma splendens Carpenter, Brit. Assn. Adv. Sci., Rept. for 1S63, p. 653, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 156, 1865; Dall, Amer. Journ. Conch., Vol. 7, p. 126, Nov., 1871; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 362, 1889, in synonymy of costalum; Dall, Bull. 112, U. S. Nat. Mus., p. 177, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 182, pi. 98, fig. 1, 1927. Type specimen: In the California State Collection, No. 530a, fide Oldroyd, at the Universitj^ of California ? Type locality: Monterey, California. Pleistocene: Upper San Pedro fauna of Santa Monica, one specimen (apparently of this species or a new variety, in the Oldroyd Collection at Stanford University). Recent: Monterey to San Diego, California (Dall). This is a small, spirally ribbed, granulose form, formerly thought to be the young of costatum. It is well figured by Williamson, and the figure is reproduced by Oldroyd. Mr. Willett has obtained this species only by dredging. Some specimens are difficult to distinguish from C. supragranosum . Clark has described a variety^ of this species from the upper Miocene of the region east of San Francisco Bay. Genus TURCICA A. Adams, 1854 Turcica A. Adams, Proc. Zool. Soc. London, Part 22, p. 37, 1854, sole species T. numilifera A. Adams, loc. cit. and pi. 27, fig. 1; Dall, U. S. Geol. Surv., Prof. Paper 59, p. 96, 1909. Ptychostylis Gabb, Proc. Calif. Acad. Sci., Vol. 3, p. 187, 1865. Thalotia of Cooper, 1867, but not of Gray, 1847, .^e Dall, 1909. Type (by monotypy), Turcica monilifera A. Adams, op. cit., p. 37, pi. 27, fig. 1, Moreton Bay, Australia; Recent. Shell conoidal, thin, subdiaphanous, imperforate; whorls with transverse series of granules, the last rounded at the periphery; columella solid, spirally twisted at the upper part, ending below or anteriorly in an obtuse prominent point; outer Up thin, simple, acute. (Adams.) This genus is closely allied to Calliostoma, from which it differs in its twisted colum- ella, thickened below. Tiu-cica caffea Gabb Turcica (Ptychostylis) caffea Gabb, Proc. Calif. Acad. Nat. Sci., Vol. 3, p. 187, 1865; Geol. Surv. Calif., Palaeo., Vol. 2, pt. 1, p. 16, pi. 3, fig. 27, 1866; pt. 2, p. 84, 1868-9. Thalotia caffea Gabb, Cooper, Geog. Cat. West Coast Shells, p. 26, 1867; 7th Ann. Rept. Calif. St. Mineralogist, p. 267, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 327, 1903. Calliostoma (Turcica) caffea Pilsbry, Tryon's Man. Conch., Vol. 11, p. 416, 1889. Turcica caffea Gabb, DaU, BuH. 112, U. S. Nat. Mus., p. 177, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, R. 3, p. 192, 1927. Pleistocene: "PUocene" of Deadman Island; one specimen from the lower San Pedro series of Deadman Island, Los Angeles County (Arnold). Recent: San Pedro, California, to Cape San Lucas, Lower California, ]Mexico (DaU). This shell looks something Uke a Calliostoma, but has two twisted fold-like pro- tuberances on the columella and a conspicuously channeled or depressed suture. * Calliostoma splendens Carpenter, var. diabloensis Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 482, pi. 65. fig. 21, 1915. 838 San Diego Society of Natural History [Memoirs Turcica gabbi Dall r%n-cica gabbi Dall, U. S. Geol. Surv., Prof. Paper 59, pi. 4, fig. 5, pi. 0, fig. 11, 1909. Type specimen: In the U. S. National Museum, No. 153,968. Type locality: Coos Bay, Oregon; Miocene. Miocene: Coos Bay and south of Fossil Point, Oregon (Dall). This species, the possible precursor of T. caffea Gabb, is more elevated and has simpler sculpture than Gabb's species. Genus CmARINA Dall, 1909 Cidarina Dall, U. S. Geol. Sur\'., Prof. Paper 59, p. 98, April, 1909. Type (by original designation), Margarita cidaris A. Adams. "Shell large, whitish, unicolor, with strong spiral sculpture, sharply nodose, the umbilicus closed by^a reflexed layer of callus, the suture channeled." (Dall, 1909.) This genus was originally differentiated as a section of Margarites Leach, in Gray, 1847. It is distinguished from Solariella by its closed umbilicus. It appears that the section Callitropis Sequenza, 1903, will have to take the place of Solar icida Dall, 1919. Cidarina cidaris (A. Adams) Plate 32, Figure 22 Margarita cidaris A. Adams, in Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 653, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 14, p. 426, Vol. 15, p. 29, 1865; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 249, 1888; Calif. St. Mining Bureau, Bull. 4, Pt. 3, p. 27, 1894. Turcicula (?) cidaris (A. Adams) Carpenter, Pilsbry, Tryon's Man. Coneh., \'ol. 11, p. 331, no figure, 1889. Solariella oxybasis Dall, Proe. U. S. Nat. Mus., Vol. 12, p. 352, pi. 12, fig. 6, 1889, fide Cooper, 1889. Solariella cidaris A. Adams, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 202, pi. 22, fig. 4, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 334, pi. 7, fig. 11, 1903. Cidarina cidaris A. Adams, Dall, Bull. 112, U. S. Nat. Mus., p. 177, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 193, pi. 91, fig. 7, 1927. Type locality: Near Neah Bay, Washington; Recent. Pliocene: San Marcial, Lower California, Mexico (Carpenter). This occurrence may be Pleistocene. Pleistocene: "Pliocene" of Deadman Island, rare, "about a dozen specimens" (Arnold). Recent: Kasaan Bay, Alaska, to Cape San Quintin, Lower California (Dall). The ventricose whorls, regularly increasing in size from the minute apex, the thin shell, and nodose, partially cancellate sculpture serve to distinguish this species. The umbilicus is sometimes partly open behind the reflected columellar lip. Genus SOLARIELLA S. Wood, 1842 Solariella S. Wood, Ann. Mag. Nat. Hist., Vol. 9, p. 531, 1842, sole species, 5. maculata S. Wood; Cossmann, Ess. Paleo. Comp., Vol. 11, pp. 259-261, 1918; Woodring, Carnegie Inst., Publ. No. 385, p. 431, 1928. Type (by monotypy), S. maculata S. Wood; Pliocene of England. Shell small, spire low, inner layer nacreous, umbilicus very wide and deep. Aperture subcircu- lar, almost parallel to the vertical axis of shell, peristome attached to parietal wall along only small part of its circtmiference. Outer lip, as viewed from above, slightly convex forward between suture and periphery of body whorl. Basal lip virtually straight. Sculpture consisting of spiral threads modified by fine axial threads. (Woodring.) Range: Cretaceous to Recent. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 839 A number, of species of Solariella have been described from the Eocene of California and Washington. It is strange that but one species has as yet been reported from the Pliocene. Solariella peramabilis Carpenter Solariella peramabilis Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 653, 1864; Proc. Calif. Acad. Nat. Sci., Vol. 3, p. 156, 1864; Cooper, 7th Ann. Rept. Calif. St. Mineralogist, p. 265, 1888; Pilsbry, Tryon's Man. Conch., Vol. 11, p. 312, pi. 67, figs. 59-61, 1889; WiUiamson, Proc. U. S. Nat. Mus., Vol. 15, p. 202, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 335, pi. 7, fig. 2, 1903; Dall, Bull. 112, U. S. Nat. Mus., p. 177, pi. 17, fig. 8, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 195, pi. 91, fig. 8, pi. 101, fig. 7. 1927; WaterfaU, Univ. Calif. Publ. Geol., Vol. IS, p. 78, 1929. Small, turbinate, with a few granulose, widely spaced spiral riblets, more nimierous and more closely spaced on the base of the body whorl; umbilicus wide open, one or two basal riblets ascend- ing spirally within. Average specimens measure 12 mm. in axial length; apical angle about 82°. Pliocene: Pico of Ventura district (Waterfall). Pleistocene: "Pliocene" of Deadman Island, Los Angeles County, rare, "four specimens" (Arnold). Recent: Forrester Island, Alaska, to San Diego and the Coronado Islands (off San Diego); also Japan (Dall). Genus MARGARITES Leach in Gray, 1847 Margarita Leach, Thompson's Ann. Phil., Vol. 14, p. 202, 1819, not of Leach, Zool. Misc., Vol. 1, p. 107, 1814, a pearl oyster; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, pp. 13, 285, 1889. Margarites Leach MS., Gray, Ann. Mag. Nat. Hist., Vol. 20, p. 271, 1847; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 406, 1892; U. S. Geol. Surv., Prof. Paper 59, p. 97, 1909. Eumargarita Fischer, Man. Conchyl., p. 825, 1885. Type (by monotypy), Helix margarita Montagu = Trochus helicinus Fabricius, 1780, = ? Turbo helicinus Phipps, 1774, a Recent species of the northern Atlantic, Arctic, and Pacific coast south to Catalina Island, California. Shell umbilicate, orbicular, conoidal or depressed, thin; not variegated; whorls rounded, smooth or spirally lirate; aperture subcircular, peristome simple, acute, the margins approacliing; columella arcuate, simple, thin. (Pilsbry.) The typical section of this genus is a boreal group, containing a number of supposed species and varieties, many of which are difficult to differentiate. The pearly shell within the aperture of some species is very pretty. Margarites, s. s., has a depressed shell of but few whorls. Lirularia and Pupillaria have rather prominent spiral sculpture and a more elevated spire. Subgenus PUPILLARIA Dall, 1909 Pupillaria Dall, U. S. Geol. Surv., Prof. Paper 59, p. 97, 1909. Type (by original designation), Trochus pupillus Gould, Bering Sea south; Recent. Shell dull, trochiform, unicolor, strongly spirally striated, sometimes radiately ribbed, and with more numerous whorls. Cliiefly temperate seas. (Dall.) There is less difference between Pupillaria and Lirularia than between either of the two and Margarites, s. s. Cidarina Dall, described as a section at the same time as the foregoing, is very distinct. Lirularia is smaller than Pupillaria. 840 San Diego Society of Natural History [Memoirs Margarites (Pupillaria) pupillus (Gould) Trochvs pupillvs Gould, Proc. Boston Soc. Nat. Hist., Vol. 3, p. 91, 1849, "New Zealand"; U. S. Expl. Exped., Vol. 12, Mollusca, p. 186, 1852, Atlas, fig. 208, 1856. Margarita piipilla Gould, DaU, Amer. Journ. Conch., Vol. 7, p. 127, Nov., 1871; Cooper, 7tli Ann. Rept. Calif. St. Mineralogist, p. 249, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 295, pi. 44, figa. 29-32, 1889; Keep, West Coast SheUs, p. 78, fig. 63, 1888, 1892; Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 202, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 333, pi. 10, fig. 15, 1903; S. S. Berry, NautUus, Vol. 22, p. 38, 1908. Margarites {Pupillaria) pupilla Gould, Dall, U. S. Nat. Mus., Bull. 112, p. 178, pi. 17, figs. 2, 10, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 200, pi. 101, figs. 2, 3, 1927. Shell small, ovate-conic, rather solid; whorls five, convex, flattened slightly above, forming a narrow, tabulated band just below the suture; body whorl obtusely angulated; surface sculptured with small, flattened, subequal, equidistant, revolving ribs, five on the upper whorls; mterspaces ornamented by fine, oblique growth lines; base of body whorl nearly flat, and ornamented with numerous fine, revolving Unes, which become coarser near the umbilicus; suture deeply impressed, distinct; aperture circular; columella somewhat arcuate; umbilicus small, groove-like; outer lip sharp; nacreous layer on the inner lip. Dimensions: Alt. 5.8 mm.; lat. 8 mm.; defl. 67 degrees. (Arnold, shghtly altered.) Type specimen: In the U. S. National Museum. Type locality: "New Zealand." Oldroyd explains the mistake in type locality as caused by transportation of the type specimen in ballast. Pliocene: Santa Barbara formation, upper Pliocene, at Bath-house Beach, Santa Barbara (Cooper; Arnold; S. S. Berry). Pleistocene: "Pliocene" at Deadman Island, Los Angeles County (Arnold). Recent: Nunivak Island, Bering Sea, to San Pedro, California; ? San Diego in deep water (Dall). Margarites (Pupillaria) cinereus (Couthouy) Margarita striata Broderip and Sowerby, Zool. Journ., Vol. 4, p. 371, 1829, (not M. striata Leach, Appendix to Ross's Voy. of Discovery H. M. S. IsabeUa and Alexander, Ed. 2, 1819); Dall, U. S. Geol. Surv., 17th Ann. Rept., Pt. 1, p. 845, 1896. Turbo cinereus Couthouy, Boston Journ. Nat. Hist., Vol. 3, p. 99, pi. 3, fig. 9, 1838. Margarita cinerea Couthouy, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 291, pi. 37, fig. 5, pi. 44, figs. 20, 25, pi. 60, fig. 29, 1889. Margarites {Pupillaria) cinerea Couthouy, Dall, Bull. 112, U. S. Nat. Mus., p. 178, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 201, 1927. Type specimen: In the Couthouy Collection, Boston ? Type locality: Massachusetts Bay. Miocene: "Miocene" of St. Paul Island and of Unalaska (DaU, 1896). Recent: Bering Strait to Port Etches, Alaska; circumboreal (Dall, 1921). This species is well supplied with synonyms. We have seen no authentic specimens. Subgenus LIRULARIA DaU, 1909 Lirnlaria Dah, U. S. Geol. Surv., Prof. Paper 59, p. 98, April, 1909. Type (by original designation), Margarita lirulata Carpenter; Recent, Alaska to San Diego, California. SheU small, dull-surfaced, with variable color patterns, strong spiral sculpture, and delicate axial sculpture. Tropical and warm temperate seas. (After Dall, alt.) Volume 1 ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 841 Margarites (Lirularia) lirulatus (Carpenter) Margarita lirulala Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 653, 1864; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 11, p. 296, pi. 65, figs. 81, 82, 87, 1889. Margarites lirulata Carpenter, Dall, U. S. Geol. Surv., Prof. Paper 59, p. 98, 1909. Margantes {Linilaria) lirulata Carpenter, Dall, Bull. 112, U. S. Nat. Mus., p. 179, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 207, pi. 101, fig. 1, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Margarites magna T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 36, pi. 2, figs. 2, 3, 5, January, 1925. Type specimen: In the U. S. National Museum. Type locality: Puget Sound. Pliocene: Pico formation, near Ventura (Waterfall). Pleistocene: Saugus formation, near Ventura (Waterfall) ; San Pedro, California (in the collection of George WiUett). Recent: Port Etches, .\laska, to San Diego, California (Dall, 1921). Thi.s species usually has rather widely spaced spiral ribs, three on the penultimate whorl, more on the body whorl, closer together around the umbilicus, which is open. The aperture is almost circular. The sculpture of lirulatus is said to be quite variable, sometimes obsolete. It may be closely related to optabilis (Carpenter). In this species as in many others there are occasional abnormally large individuals or even schools of such exceptional specimens which do not have any claim to nomen- clatorial recognition. They appear both in the fossil and in the Recent fauna and probably reflect some condition peculiarly favorable to increase in size. "Margarites magna" T. S. Oldroyd applies to large sized specimens of M. lirulatus. Margarites (Lirularia) condoni Dall Margarites (Lirvlaria) condotri Dall, U. S. Geol. Surv., Prof. Paper 59, p. 98, pi. 6, figs. 7, 8, April, 1909. Type specivien: In the U. S. National Museum, No. 153,922. Type locality: Coos Bay, Oregon; upper Miocene. Miocene: At the type locality (Dall). This species has a less depressed body whorl than M. pupillus, but seems to be related. Dall gives it an elaborate description and places it in Lirularia. Margarites (? Lirularia) johnsoni Arnold Margarites johnsoni Arnold, U. S. Geol. Surv., Bull. 396, p. 69, pi. 15, fig. 6, January 15, 1910; Bull. 398, pi. 37, fig. 6, 1910; Nomland, Univ. Calif. Publ. Geol, Vol. 10, p. 221, 1917. Type specimen: In the U. S. National Museum, No. 165,66.3. Type locality: On Jasper Creek just above Jacalitos Creek, Coalinga district, Cali- fornia ; lower Pliocene. Pliocene: Jacalitos formation, Coalinga district (Arnold); "Chione elsmerensis zone," lower Etchegoin Pliocene, Coalinga district, common (Nomland). According to Arnold, this species can be distinguished from M. pupillus (Gould) by "its smaller size, less convex whorls, less conspicuous suture, and much coarser but fewer spiral lines on base. The species is easily distinguishable from Leptothyra by its higher spire, perforate umbilicus, and more prominent oblique incremental sculpture." 842 San Diego Society of Natural History [Memoirs Margarites (Lirularia) optabilis (Carpenter) variety knechti (Arnold) Margarita oplabilis Carpenter, var. knechti Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 332, pi. 5, fig. 14, 1903. Margarita optabilis knechti Arnold, Berry, Nautilus, Vol. 22, p. 38, 1908. Margarites optabilis knechti Arnold, Dall, U. S. Nat. Mus., Bull. 112, p. 179, 1921. Shell small, conical, thin; apical whorls turbinated; whorls five; upper whorls rather angular, slightly tabulated above; body whorl rounded, slightly angulated at base; two prominent spiral ridges, one at angle of whorl, the other near anterior margin; between these two ridges a slight concave surface sometimes ornamented with famt spiral ridges; oblique growth Lines quite promi- nent; suture impressed and distinct; base of body whorl only slightly convex and ornamented by five spiral ridges; lunbilicus large, deep, effuse, smooth; aperture subrotund; iiuier lip incrusted and projecting slightly over mnbilicus. Dimensions: Alt. 8.5 mm.; lat. 8 mm.; body whorl 6.5 mm.; aperture 4.5 mm.; defl. 70 degrees. (Arnold, alt.) Type specimen: In the U. S. National Museum. Type locality: San Pedro, Los Angeles County; Pleistocene. Pliocene: Santa Barbara formation, upper Pliocene, Bath-house Beach outcrop, Santa Barbara (Berry). Pleistocene: "Common in lower and rare in upper San Pedro series of San Pedro" (Arnold). This variety is very close to the typical formi but appears to be a little higher spired. Margarites (Lirularia) optabilis (Carpenter) variety nodosus (Arnold) Margarita optahilis Carpenter, var. nodosa Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 332, pi. 5, fig. 13, 1903. Margarites (Lirularia) optabilis nodosa Arnold, Dall, U. S. Nat. Mus., Bull. 112, p. 179, 1921. Type specimen: In the U. S. National Museum. Type locality: San Pedro, Los Angeles County; lower Pleistocene. Pleistocerte: Lower San Pedro series of San Pedro and Deadman Island, Los Angeles County (Arnold). "This variety is distinguishable by its simple conical shape, flat whorls, and nodose ridges." (Arnold.) Margarites (Lirularia) parcipictus (Carpenter) variety pedroanus (Arnold) Margarita parcipicta Carpenter, var. pedroana Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 333, pi. 5, fig. 16, 1903. Margarites (Lirularia) parcipicta pedroana Arnold, Dall, U. S. Nat. Mus., Bull. 112, p. 179, 1921. Shell small, thin, globular, conical; spire elevated, subacute; whorls four, roimded, tabulated near posterior margin; four spiral ridges on upper whorls; suture deeply impressed and distinct; base of body whorl romided and ornamented by fiiie spiral ridges; umbilicus deep and effuse; aperture subcircular. Dimensions: Alt. 5.5 mm.; lat. 5.5 mm.; body whorl 4.5 mm.; aperture 3 mm.; defl. 80 degrees. (Arnold.) Type specivien: In the U. S. National Museum. Type locality: San Pedro, Los Angeles County; Pleistocene. Pleistocene: Lower San Pedro series at Deadman Island and San Pedro; upper San Pedro series at Deadman Island, San Pedro, and Los Cerritos (Arnold). The typical variety, which is figured by Dall,^ ranges in the Recent fauna from Sitka, Alaska, to San Martin Island, Lower California, Mexico (Fred Baker, MS.). 1 Brit. Assn. Adv. Sci., Kept, for 1863, p. 653, 1864; Proc. Calif. Acad. Nat. Sci., Vol. 3, p. 214, 1865; figured by Dall, U. S. Nat. Mua., Bull. 112, p. 179, pi. 17, fig. 7, Feb., 1921; Recent. Santa Barbara to San Pedro, California. 2 Bull. 112, U. S. Nat. Mus., p. 179, pi. 17, fig. 3, 1921. VoLiTME I ] Pliocene and Pleistocene Molltjsca of California 843 Family CYCLOSTREMATIDAE Genus VITRINELLA C. B. Adams, 1850 Vitrinella C. B. Adams, Monograph of Vitrinella, p. 3, 1850; Pilsbry, Tryon's Man. Conch. Ser. 1, Vol. 10, p. 15, 1888; Bush, Trans. Conn. Acad. Arts and Sci., Vol. 10, p. 105, 1897; Woodring, Carnegie Inst., Publ. No. 385, p. 438, 1928. Type (by subsequent designation, Bush, 1897), Vitrinella helicoidea C. B. Adams, figured by Pilsbry, op. cit., p. 102, pi. 34, figs. 40, 41, 1888, Jamaica; Recent. Shell small, thin, with a Helix-like low spire and a very wide umbilicus; sculpture absent except for growth lines; aperture ovate, with margin projecting forward between the suture and the periph- ery of the body whorl; callus deposit on parietal wall. It is probable that Vitrinella should be considered a subgenus of Cyclostrema. Section Vitrinella, s. s. Vitrinella williamsoni Dall Vitrinella williamsoni DaU, Proc. U. S. Nat. Mus., Vol. 15, p. 202, pi. 21, figs. 2, 3, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 335, 1903; Dall, U. S. Nat. Mus., Bull. 112, p. 181, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, p. 216, pi. 106, figs. 4, 6, 1927. Type specimen: In the U. S. National Museum, No. 106,856. Type locality: San Pedro, California; Recent. Pleistocene: Lower San Pedro series of Deadman Island, "rare"; upper San Pedro series of San Pedro, Los Angeles County (Arnold). Recent: San Pedro, California (Dall, 1921). This is a strongly flattened species. Arnold found nearly perfect specimens in the lower San Pedro series of Deadman Island. Vitrinella thomasi Bartsch Vitrinella thomasi Bartsch, Proc. Biol. Soc. Wash., Vol. 31, p. 79, July 29, 1918. Pleistocene: Nob Hill cut, San Pedro, Los Angeles County (Bartsch). This form is like V. williamsoni Dall, but it is smaller and less depressed. It is probable that it should be considered a variety or variation of the latter. Vitrinella eshnauri Bartsch Vitrinella eshnauri Bartsch, Proc. U. S. Nat. Mus., Vol. 32, p. 168, text figs. 2a-c, February 8, 1907; Berry, Nautilus, Vol. 21, p. 46, 1907; Dall, U. S. Nat. Mus., Bull. 112, p. 181, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 247, 1926; I. S. Oldroyd, Stanford Univ. Publ, Geol., Vol. 2, Pt. 3, p. 217, pi. 106, figs. 5, 7, 9, 1927. Type specimen: In the U. S. National Museum, No. 127,557. Type locality: San Pedro, California; Recent. Pleistocene: Upper Pleistocene at f-'an Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro (Bartsch; Dall); Monterey (Berry). This is a higher spired shell than V. williamsoni. The aperture is nearly circular. Section Docomphala Bartsch, 1907 Shell Uke that of tji^ical Vitrinella except that the inner half of the columellar wall of the um- bilicus is marked by strong, obhque, rounded ribs, and the whorls of the spire may show axial ribs. 844 San Diego Society of Natural History [Memoirs Vitrinella steamsi Bartsch Vilrinella {Docomphala) steamsi Bartsch, Proc. U. S. Nat. Mus., Vol. 32, p. 169, text figures ia-c, February 8, 1907; I. S. Oldroyd, Stanford Univ. Publ, Geol., Vol. 2, Pt. 3, p. 218, pi. 106, figs. 11, 13, 14, 1927. Vitrinella steamsi Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 181, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 247, 1926. Pleistocene: Upper Pleistocene at San Qiiintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California (Dall, 1921). This species is bluntly carinated at the basal margin of the umbilical opening. Genus DELPHINOIDEA Brown, 1827 Delphinoidea Brown, Illust. Conch. Gt. Brit. Irel., p. 4, pi. 51, fig. 32, 1827; Ed. 2, p. 20, 1844; Gray, Proc. Zool. See. London for 1847, p. 152, 1847. Type (by subsequent designation, Gray, 1847), Helix serpuloides Montagu, figured by Brown, op. cit., Ed. 2, p. 21, pi. 8, figs. 40, 41, 1844, coasts of Europe; Recent. Shell small, HelixAike, smooth or spirally striated, umbilicus large, wide. This genus should be compared with Skenea Fleming. It is at least in part the Cyclo- stremella as used by Bartsch, not Cyclostremella Bush. Delphinoidea Brown, 1827, does not seem to have had a prior generic use. Delphinoidea coronadoensis Arnold Delphinoidea coronadoensis Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 320, 1903. Shell minute, orbicular, depressed, milk-white, rather thick for size of shell; spire flattened beneath plane of upper periphery of the body whorl; whorls two and one-half, nearly circular in cross-section; surface ornamented by numerous subequal, romided spiral ridges, and very minute transverse lines, the whole giving the surface a cancellated appearance ; irregular lines denoting inter- ruption in growth are common on the body whorl; suture deeply appressed; umbilicus wide, deep; aperture suboval ; peristome continuous, rather thick, slightly effuse. Dimensions : Maximum diame- ter, 2 mm. ; altitude, 0.9 mm. (Arnold.) Type locality: Spanish Bight, North Island, San Diego, California; Pleistocene. The typical variety appears to have stronger striations and more deeply depressed' sutures than variety calif ornica Bartsch. They are very closely related. Delphinoidea coronadoensis Arnold variety califomica (Bartsch) Cyclostremella califomica Bartsch, Proc. U. S. Nat. Mus., Vol. 32, p. 174, text figures lOa-c, February 8, 1907; Dall, U. S. Nat. Mus., Bull. 112, p. 182, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 223, pi. 106, figs. 1-3, 1927. Type locality: Long Beach, California; Recent. Pleistocene: San Diego, California (Bartsch). Recent: Monterey, to San Diego, California (Bartsch). This variety is very close to the typical form, and larger collections probably will show that individual variation accounts for the differences. If so, caUfornica should be synonymized. Specimens in the collection of Mr. George Willett of the Los Angeles Museum suggest that the variety califomica has less depressed sutures and less distinct spiral striations. ^ Arnold stated that the sutures were "deeply appressed." possibly meaning depressed. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 845 Superfamily Zygobranchia Family HALIOTIDAE Genus HALIOTIS Linnaeus, 1758 The genus Haliotis Linnaeus may be subdivided into a number of sections (or sub- genera) which cannot be discussed here. The species listed below belong to Haliotis, sensu lato, though the modern tendency toward fine subdivisions may result in their separation into two groups. So far as known, Haliotis first made its appearance in California in the upper Cre- taceous, one species having been described from the Chico formation of Point Loma, San Diego, by F. M. Anderson. ^ At least one species is known from the Miocene of southern California and several occur in the Pliocene and Pleistocene. Abalones are a source of food in California and Lower California, but the danger of extinction has required legal protection for the species in the United States. The Cali- fornia Recent species are shallow- water forms, sedentary in habits, and feed on sea lettuce, eel grass, rock kelps, and diatoms.- Haliotis comigata Gray Haliotis corrvgata Gray, in Wood's Index Test., Suppl., pi. 8, fig. 5, 1828; Reeve, Conch. Icon., Vol. 3, Haliotis, pi. 4, fig. 12, 1846; Sowerby, Thes. Conch., Vol. 5, p. 19, fig. 26 (excl. var.), 1882; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 80, pi. 5, fig. 24, 1890; Dall, U. S. Nat. Mus., BuU. 112, p. 184, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 236, 1927. Haliotis nodosa Philippi, Zeitschr. f. Malak, p. 149, October, 1845; Abbild. Beschreib., Vol. 2, p. 1.57, pi. 5, and pi. 6, fig. 1, 1847. Shell large, subcLrcular, or short oval, very convex, like a half-globe; surface corrugated, the wrinkles nodose ; perforations elevated, tubular, three open ; muscle scar distinct, roughened. Length, 155 mm.; -nddth, 122 mm.; convexity, 57 mm. (After Pilsbry.) Pliocene: Middle Pliocene of S. D. S. N. H. locality 223, O'Hare Canyon, Ventura County, one specimen (H. R. G.) ; in excavation for Los Angeles Public Library, Los Angeles, California, thirty feet below surface, lower part of upper Pliocene (in collection of Los Angeles Museum). Recent: Monterey, California, to San Quintin Bay, Lower Cahfornia (DaU). This species is easily distinguished by its outline and convexity, its rough surface, and tubular perforations. The one specimen collected in O'Hare Canyon, Santa Paula Quadrangle, broke into many pieces when being extracted from the conglomerate bed in which it was found, but its shape and a single very tubular perforation which survived served to identify it. Haliotis rufescens Swainson Haliotis rufescens Swainson, Cat. Shells Bligh, Appendix, p. 2, 1822; Reeve, Conch. Icon., Vol, 3, Haliotis, pi. 2, fig. 6, 1846; Sowerby, Thes. Conch., Vol. 5, p. 18, fig. 3.5, 1882; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 82, pi. 20, fig. 11, 1890; Packard, Univ. Calif. Pull. ZooL, Vol. 14, p. 306, pi. 33, 1918; E. P. and E. M, Chace, Lorquinia, Vol. 2, p. 42, 1919; DaU, U. S. Nat. Mus., Bull, 112, p. 184, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 232, pi. 90, fig. 2, pi, 89, fig. 2, 1927; Boimot, Calif. Fish and Game, Vol. 16, p, 20, text fig. 10, 1930. ? Haliotis ponderosa Adams, Amer. Journ, Sci. Aits, Ser. 2, Vol. 6, p, 138, 1848, fide Pilsbry, 1890. ? Haliotis cf. rufescens Swainson, Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 449, 1926. 1 Cretaceous Deposits of the Pacific Coast, Proc. Calif. Acad. Sci., Ser. 3 (Geology), Vol. 2, p. 75, pi. 9, fig. 183, December 24, 1902. Haliotis lomatnsis F. M. Anderson, from the "Lower Chico" of Point Loma. The type specimen is preserved in the paleontological collections of the California Academy of Sciences, having endured the San Francisco earthquake and fire of 1906. It is small in size and may be a young indi\'idual or possibly not a true Haliotis. 2 See "Abalones in California" by Paul Bonnot, California Fish and Game, Vol. 16, no. I, pp. 15-23. text figures. January, 1930. 846 San Diego Society of Natural History [Memoibs Shell large, heavy and solid, oval, not very convex; sculptvire consisting of unequal spiral cords and threads, finer than m H. fulgens, and wide, low, obliquely radiating waves. Below the row of holes there is a depression, followed by a low ridge bearing usually large, low, obtuse tubercles. Spire not projecting above general curve of the back; muscle scar large, a portion of it roughened by coarse raised cords which take a spiral direction. The columellar plate is rather narrow, its lower part sloping in somewhat. Perforations large, tubular or irregular, 3 or 4 open. Length, 185-235 mm.; width, 150-185 mm.; convexity, 40-58 mm. (Modified from Pilsbry.) Pliocene: S. D. S. N. H. locality 225, between Timber Canyon and Santa Paula Creek, Ventura County, fragments of one specimen (H. R. G.) ; ? Cedros Island, Lower California, Mexico (Jordan and Hert- lein). Pleistocene: Chiton bed at Point Firmin, Los Angeles County (Chace). Recent: Bodega Bay, California, to La Paz, Lower California, Mexico (Dall). This species is distinguished by its large, heavy shell, light spiral sculpture, and radiating waves. Living specimens of this species are known as the red abalone, on account of the dull brick-red color of the exterior of the shell. Curtner' determined that California specimens six inches in diameter were nine years old, those eight inches in diameter, thirteen years old. Haliotis fulgens Philippi Haliotis Julgens Philippi, Zeitschr. f. Malak., p. 150, October, 1845; Abbild. Beschreib., Vol. 2, p. 220, pi. 7, pi. 8, fig. 1, 1847; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 574, 1864; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 81, pi. 12, figs. 61, 62, 1890; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 336, 1903; Packard, Univ. Calif. Publ. ZooL, Vol. 14, p. 306, 1918; Dall, U. S. Nat. Mus,, Bull. 112, p. 184, 1921; Oldroyd, Stan- ford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 233, 1927; Bonnot, Calif. Fish and Game, Vol. 16, p. 18, 1930. Haliotis splendens Reeve, Conch. Icon., Vol. 3, Haliotis, pi. 3, fig. 9, 1846; Proc. Zool. Soc. London for 1846, p. 54; and of authors generally. Haliotis planilirata Reeve, op. cit., pi. 3, fig. 62, (young), fide Pilsbry, Tryon's Man. Conch., pi. 19, fig. 9, 1890. Pliocene: S. D. S. N. H. locality 202, lower Pliocene of Elsmere Canyon, Los Angeles County, one specimen (H. R. G.). Pleistocene: Upper San Pedro series of Deadman Island, Los Angeles County; also Spanish Bight, San Diego, one specimen from each locality (Arnold). Recent: Farallone Islands (Carpenter) and Catalina Island, California, to Gulf of California, Mexico (Dall). This species is distinguished by its spiral sculpture, moderate convexity, angle at the row of holes, and keel. Recent specimens are known as the green abalone, having been extensively collected for food in southern California and Lower California, Mexico. The species is uncommon north of Point Conception. Arnold stated that Cooper's records of Haliotis referred to Indian kitchen midden deposits in which abalones are sometimes found. Haliotis cracherodii Leach Haliotis cracherodii Leach, Zool. Misc., Vol. 1, p. 131, 1814; Reeve, Conch. Icon., Vol. 3, Haliotis, pi. 7, fig. 23, 1846; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 79, pi. 10, figs. 52, 53, 1890; E. P. and E. M. Chace, Lor- quinia, Vol. 2, p. 42, 1919; Dall, U. S. Nat. Mus., Bull. 112, p. 183, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 230, 1927; Bonnot, Calif. Fish and Game, Vol. 16, pp. 20, 22, te.xt fig. 11, 1930. Haliotis cracherodii var. splendidula Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. IDS, 1892. Haliotis cracherodii, var. holzneri Hemphill, Trans. San Diego Soc. Nat. Hist., Vol. 1, no. 2, p. 4, 1907; Dall, U. S. Nat. Mus., Bull. 112, p. 183, pi. 20, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 231, 1927. Haliotis craclierodii, new form imperforata Dall, Proc. U. S. Nat. Mus., Vol. 56, p. 370, Aug. 30, 1919. Haliotis cracherodii imperforata Dall, U. S. Nat. Mus., Bull. 112, p. 184, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 231, 1927. Haliotis cracherodii splendidula WiUiamson, Dall, U. S. Nat. Mus., Bull. 112, p. 184, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 231, 1927. Haliotis cracherodii lusus Finlay, Trans. New Zealand Inst., Vol. 57, (for 1926), p. 492, 1927, new name for H. c. imperforata Dall, preoccupied. * W. W. Curtner, Master of Arts Thesis, Stanford University, May, 1917. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 847 Pleistocene: Chiton Bed, Point Firmin, Los Angeles County (Chace). Recent: Coos Bay, Oregon, to Santa Rosalia, Lower California, Mexico (Dall, 1921). The black abalone is easily distinguished by its dark color and by the nearly smooth exterior surface of the shell. It is inferior in food qualities to the green abalone, H.fulgens Philippi. Bonnot found the species exceedingly abundant at low tide on the rocks on San Miguel Island. It seems to favor rocks not thickly covered with algse and is supposed to subsist on diatoms. The occasional shells which have no open holes are abnormal individuals. They have been uselessly named as varieties three times. Some shells have a supplementary deposit of brilliant pearly appearance in the center of the interior of the shell which mislead Williamson to name them as a distinct variety (splendidula) . Such peculiarities in the shell occur sporadically and have no claim to taxonomic recognition. A similar phenomenon occurs in H. californiensis and perhaps in others also. Haliotis californiensis Swainson' may be a distinct species. It has numerous (about 14) small round holes, the margins of which stand out but very little from the exterior surface of the shell. Some individuals have a supplementary shell deposit in the interior which is an individual peculiarity forming the basis of the useless name bonita Orcutt.^ Family FISSURELLIDAE Shell conical, limpet-shaped, non-spiral (but with a spiral nucleus), having a perforation, anterior slit, notch, or emargination for the passage of the anus; not nacreous; having a horseshoe- shaped impression of the adductor muscle; bilaterally symmetrical. (Pilsbry, 1890.) Subfamily Fissurellinae Apex of shell wholly removed by the anal perforation, which is bounded inside by a callus with entire margms, not truncated or excavated posteriorly. Central tooth of the radula narrow. Shell wholly external, capable of containing the entire animal. (Pilsbry.) Genus FISSURELLA Bruguiere, 1789 Fissurella Bruguiere, Encycl. Method., Vers, Vol. 1, p. xiv, 1789, genus without species; Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 78, 1799; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 142, 1890; Woodring, Car- negie Inst., Publ. No. 38.5, p. 449, 1928. Type (by monotypy, Lamarck, 1799), Patella nimbosa Linnaeus, figured by Pilsbry, op. cit., p. 163, pi. 36, fig. 32, 1890, Caribbean region; Recent. Fissurella volcano Reeve Fissurella volcano Reeve, Conch. Icon., Vol. 6, Fissurella, pi. 4, fig. 2, 1849; Sowerby, Thes. Conch., Vol. 3, p. 192, pi. 239, fig. 87, 1862; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 240, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 1.56, pi. 62, figs. 16-18, 1890; Keep, West Coast SheUs, p. 96, fig. 81, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 340, 1903; Keep, West American SheUs, p. 259, fig. 291, 1904; Revised Ed., p. 249, fig. 248, 1911; Dall, NautUus, Vol. 32, p. 24, 1918; E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919; Dall, U. S. Nat. Mus., Bull. 112, p. 184, 1921; Stephens, Trans. San Diego Soc. Nat. Hist., Vol. 5, p. 253, 1929. Fissurella ornala Nuttall MS., Carpenter, Proc. Zool. Soc. London for 1856, p. 222, fide Pilsbry, 1890. Fissurella volcano Reeve, variety crucifcra DaU, Proc. U. S. Nat. Mus., Vol. 34, p. 256, 1908. Sribemarginula golischse DaU, Nautilus, Vol. 30, p. 61, October, 1916. 1 Zool. Illustr., Vol. 2, pi. 80, December, 1821; Reeve, Conch. Icon., Vol. 3, Haliotis, pi. 8, fig. 26, 1846; Dall, U. S. Nat. Mus., Bull. 112, p. 184. 1921; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 3, p. 232. pi. 86, figs. 1, 2, 1927. ! West American Scientist (San Diego), Vol. 10, no. 5, p. 30, 1900. 848 San Diego Society of Natural History [Memoirs Fissurella volcano cnicifera Dall, U. S. Nat. Mus., Bull. 112, p. 184, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 246, 1927. Hemitoma golischse Dall, U. S. Nat. Mus., Bull. 112, p. 186, pi. .5, fig. 2, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 238, pi. 85, fig. 2, 1927. Pleistocene: Lower San Pedro series of Deadman Island and San Pedro, common; upper San Pedro series at Deadman Island, Los Cerritos, Craw'fish George's, and San Pedro (Arnold); chiton bed on Point Firmin (Chace); Pacific Beach (Arnold) and the west side of Point Loma (Stephens), San Diego; Magdalena Bay, Lower California, Mexico (DaU, 1918). Recent: Crescent City, California, to Panama (Dall, 1921). The form called variety crudfera is an individual variant with radial white bands; it occurs sporadically and is of no taxonomic value. Rarely, some individuals show a partial obsolescence of the apical perforation; the extreme form with an entirely imper- forate apex was named Subemarginula golischce by Dall. The type of the latter is in the U. S. National Museum. Subfamily Fissurellidinae Animal much too large to be included in the shell, even when contracted in preservatives. Rhachidian tooth far broader than the laterals, not narrowed above. Shell with the apex removed by a large perforation, which is bounded inside by an entire, not truncated, callus rim. (From Pilsbry, 1890.) Genus MEGATHURA PUsbry, 1890 Megathura Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 182, 1890; Iredale, Proc. Malac. Soc. London, Vol. 12, p. 328, 1917. Type (by monotypy), Megathura calif ornica Nuttall MS., Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 182, 1890, = Megathura crenulata (Sowerby). Megathura crenulata (Sowerby) Fissurella crenulata Sowerby, Cat. Tankerville, Appendi.x, p. vi, 1825. Lucapina crenulata Sowerby, Tryon, Struct. Syst. Conch., Vol. 2, p. 326, pi. 83, fig. 17, 1883; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 182, pi. 44, figs. 95, 96, 1890; .\rnold, Mem. Calif. Acad. Sci., Vol. 3, p. 337, 1903; Keep, West American Shells, p. 260, fig. 293, 1904; Revised Ed., p. 251, fig. 250, 1911. Macrochasma crenulata Sowerby, E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919. Megathura crenulata Sowerby, Dall, U. S. Nat. Mus., Bull. 112, p. 185, 1921; E. K. Jordan, Bull. So. Calif. Acad. Sci., Vol. 23, p. 150, 1924; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 243, 1927. Pleistocene: Lower Quaternary at Magdalena Bay, Lower California, Mexico (Jordan); upper San Pedro series at Los Cerritos (Arnold); chiton bed at Point Firmin, Los Angeles County (Chace). Recent: Monterey Bay, California, to Cedros Island, Lower California, Mexico (Dall, 1921). Genus MEGATEBENNUS PUsbry, 1890 Megatebennus Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, pp. 178, 182, 1890. Type (by original designation^), Fissurellidea bimaculata Dall. Edges of shell elevated at each end, blunt at the sides, in adults not crenulated. (Pilsbry.) Lucapina Gray^ differs in that the edges of the shell are nearly in a plane, are finely crenulated and are not elevated at the ends. For an excellent discussion of the Fis- surellidcE the reader is referred to Pilsbry's monograph in the twelfth volume of Tryon's Manual of Conchology (Series 1). 1 Pilsbry, op. cit., p. 182, stated: "F. bimaculata Dall may be considered the type." It is the only species he included in the typical section, all the others being placed in Section Amhlychilepas Pilsbry, 1890, type (by original designation), F. Irapezina Sowerby. 2 Synop. Cont. Brit. Mus., p. 151, 1840, nomen nudum; Gray in Sowerby. Conch. lUustr., Fissurella, p. 4, No. 38, fig. 29, June, 1835, Lucapina elegans; Gray, Proc. Zool, Soc. London for 1847, p. 147, 1847; Guide Syst. Distr. Moll. Brit. Mus., p. 166. 1857, diagnosis: Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, pp. 181-182, 1890; Dall, Proc. U. S. Nat. Mus., Vol. 48. p. 437, 1915: not of H. and A. Adams, Gen. Rec. Moll., Vol. 1. p. 447, 1858. Volume I ] PlIOCENE AND PLEISTOCENE MoLLXJSCA OF CALIFORNIA 849 Megatebeiinus bimaculata (Dall) Fissurellidea bimaculata Dall, ,\iner. Journ. Coneh., Vol. 7, p. 132, pi. 15, fig. 7, 1871. Fissurellidsea bimaculata Dall, Keep, West Coast Shells, p. 97, fig. 82, 1888, 1892. Clypidella bimaculata Dall, Gabb, Geol. Surv. Calif., Palaeo., Vol. 2, pp. 86, 124, 1868-9; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 235, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 339, 1903. Megatcbennus bimaculata Dall, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 183, pi. 44, fig. 94, 1890. Megatebcnnus himaadatus Dall, U. S. Nat. Mus., Bull. 112, p. 185, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 3, p. 243, pi. 85, fig. 15, 1927. Type locality: Monterey, California; Recent. Pleistocene: Lower San Pedro series of Deadman Island and San Pedro, "not uncommon"; "rare" in upper San Pedro series of Los Cerritos and San Pedro, Los Angeles County (Arnold). Recent: Forrester Island, Alaska, to Cape San Lucas, Lower California, Mexico (Dall). Genus LUCAPINELLA PUsbry, 1890 LucapincUa Pilsbrj', Tryon's Man. Conch., Ser. 1, Vol. 12, pp. 179, 195, December 16, 1S90. Type (by original designation), Clypidella callomarginata Carpenter. Shell oblong, apex subcentral, wholly removed by a rather large oblong perforation margined •n-ithin by an mitruncated callus; edge of shell blunt, scarcely crenulated in adults except in front and behind; sculptured with scaly riblets; front and side margins level, posterior margm a little elevated. Lucapinella callomarginata (Carpenter in Dall) Clypidella callomarginata Cpr., Dall, Amer. Journ. Conch., Vol. 7, p. 133, pi. 15, fig. 8, 1871; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 235, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 340, 1903. Lucapinella callmnarginata Carpenter, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 196, pi. 44, figs. 3-5, pi. 61, figs. 1-5, 1890. Lucapinella callmnargittata (Carpenter MS.), Dall, TJ. S. Nat. Mus., Bull. 112, p. 185, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 244, pi. 85, fig. 16, 1927. Pleistocene: San Pedro to San Diego (Cooper); lower San Pedro series of Deadman Island and San Pedro, "rare"; upper San Pedro series of Crawfish George's, Los Cerritos, and San Pedro (Arnold). Recent: Bodega Bay, California, to Magdalena Bay, Lower California, Mexico (Dall, 1921). Gabb's use of this name' is a nomen nudum, and as Gabb no doubt referred to the same shell for wluch Dall later fm-nished a description, it can hardly be considered as preoccupying the name. Subfamily Emarginulinae Apex of shell generally not removed, the anal tube occupying an anterior slit, not a sinuation ; or if apex be removed, by a perforation, the hole is provided internally ^ath a shelf or septum projecting forward and downward from behind it, or if bomided by a callus, the latter is truncated or excavated posteriorly. (Pilsbry, 1890.) Genus DIODORA Gray, 1821 Diodora Gray, London Med. Repos., Monthly Journ. and Review, V'ol. 15, p. 233, 1821; Iredale, Proc. Malac. Soc. London, Vol. 11, p. 331, 1915; Woodring, Carnegie Inst., Publ. Xo. 385, p. 452, 1928. Diadora Gray, Proc. Zool. Soc. London for 1847, p. 147, 1847; and of authors. Glyphis Carpenter, Proc. Zool. Soc. London for 1856, p. 223, footnote; Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 220, 1857; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 202, 1890; not Glyphis Agassiz, 1843. Type (by monotypy^), Patella apertura Montagu, Test. Brit., p. 491, pi. 13, fig. 10, 1808. 1 "Clypidella callomarginaCa, Cpr.; Brit. Assn. Rept. 1866. Post-Pliocene, San Pedro. Living," Gabb, Geol. Surv. Calif., Palso., Vol. 2, p. 86, 1868-9. - Reference to Gray, 1821, and genotype is according to Woodring. 1928. 850 San Diego Society of Natural History [Memoirs Apex in front of the middle, absorbed by tlie hole, the latter bounded inside by a distinct oval hole-callus, truncated behmd. (Pilsbry, description of Glyphis.) Woodring has pointed out that Diodora is the correct spelling of this generic name, dating from Gray's original use of it in 1821. The later (1847) emendation, even though more in accord with classical usage, cannot be followed under the present rules of nomen- clature. Diodora aspera (Eschscholtz in Rathke) Fissurella aspera Eschscholtz, in Rathke, Zool. Atlas, Pt. 2, p. 21, pi. 23, fig. 5, 1833. Glyphis aspera Eschscholtz, Carpenter, Proc. Zool. Soc. London for 1856, p. 223; Brit. Assn. Adv. Sci., Kept, for 1863, p. 651, 1864; Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 241, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 214, pi. 36, figs. 28-30, 1890; Keep, West Coast Shells, p. 96, fig. 80, 1888, 1892. Fissuridea aspera Eschscholtz, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 197, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 338, 1903; Keep, West American Shells, Revised Edition, p. 250, fig. 249, 1911. Diadora asppra Eschscholtz, Dall, U. S. Nat. Mus., Bull. 112, p. 185, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 247, 1926; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 237, pi. 85, fig. 11, pi. 93, fig. 1, 1927. Type locality: Sitka, Alaska; Recent. Pleistocene: Lower San Pedro series at Deadman Island and San Pedro, "not uncommon"; upper San Pedro series at Crawfish George's, common; also present at Deadman Island, San Pedro, and Los Cerritos (Arnold); Santa Barbara to San Pedro (Cooper); Santa Monica (Oldroyd Collection at Stanford University); upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Cook's Inlet, Alaska, to Magdalena Bay, Lower California, Mexico (Dall). Diodora lincolni (Gray, in Sowerby), D. cratitia (Gould, 1846), and D. densiclathrata (Reeve) appear to be synonyms. The type figure of aspera has been reproduced by Oldroyd. Diodora inaequalis (Sowerby) Fissurella inseqiialis Sowerby, Proc. Zool. Soc. London, Pt. 2, p. 126, March, 1835; Reeve, Conch. Icon., Vol. 6, Fissurella, pi. 7, fig. 50, 1849; Carpenter, Brit. Assn. Adv. Sci., Rept. for 1856, p. 184, pi. 7, figs. 4a-n, explana- tion of plate on p. 3, 1857. ? Fissurella pica Sowerby, Proc. Zool. Soc. London for 1834, p. 126, 1834; Reeve, op. nt., pi. 7, fig. 49, 1849. f Fissurella mus Reeve, Conch. Icon., Vol. 6, Fissurella, pi. 16, fig. 120, 1850. Glyphis insqualis Sowerby, Carpenter, Brit. Assn. Adv. Sci., Rept. for 1S63, p. 622, 1864; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 215, pi. 34, fig. 63, 1890. Fissuridea ing'qualis Sowerby, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 338, 1903; Dall, Proc. U. S. Nat. Mus., Vol. 37, p. 243, 1909. Diadora inxgualis Sowerby, Dall, U. S. Nat. Mus., Bull. 112, p. 185, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 236, 1927. Type locality: Galapagos Islands; Recentc' Pleistocene: Upper San Pedro series of San Pedro, Deadman Island, Long Beach, and Los Cerritos (Arnold). Recent: Santa Barbara, California, to Mantua, Ecuador, and the Galapagos Islands (DaU, 1921). Diodora murina (Carpenter in DaU in Orcutt) Fissurella (Glyphis) murina Carpenter, Dall, in Orcutt, Proc. U. S. Nat. Mus., Vol. 8, p. 543, 1885. Fissuridea murina (Carpenter) DaU, in Williamson, Proc. U. S. Nat. Mus., Vol. 15, pp. 197-199, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 339, 1903. Fissuridea murina Carpenter, Arnold, Proc. U. S. Nat. Mus., Vol. 32, p. 545, pi. 50, figs. 3, 3a, 1907; U. S. Geol. Surv., Bull. 309, pi. 40, figs. 3, 3a, 1907. Diadora murina (Carpenter MS.), DaU, U. S. Nat. Mus., Bull. 112, p. 185, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 237, 1927. Type locality: Catalina Island, fide Oldroyd; originally reported at San Diego. Pliocene: Third Street tunnel, Los Angeles (Arnold, 1907). Pleistocene: Lower and upper San Pedro series of the San Pedro region (Arnold). Recent: Crescent City, California, to Magdalena Bay, Lower California, Mexico (DaU). Volume I] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 851 Diodora subelliptica (Nomland) Fissuridea subelliplica Nomland, Univ. Calif. Publ. Geol., Vol. 9, p. 205, pi. 10, figs. 5a, 56, February 24, 1916; Vol. 10, p. 221, 1917. Pliocene: Rare and restricted to the TurrUella nova zone of the lower Pliocene of the Coalinga district (Nom- land). Diodora unica (Nomland) Fissuridea unica Nomland, Univ. Calif. Publ. Geol., Vol. 10, p. 234, pi. 11, figs. 3, 3a, 36, April 19, 1917. Pliocene: In the upper Etchegoin, Peclen coalingensis zone, Coalinga district (Nomland). Genus PUNCTURELLA Lowe, 1827 Punclurella Lowe, Zool. Journ., Vol. 3, p. 78, January, 1827; Forbes and Hanley, Hist. Brit. Moll., Vol. 2, p. 473, 1853; Dall, Bull. Mus. Comp. Zool., Harvard Coll., Vol. 9, p. 74, 1881; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 228, 1890; Woodring, Carnegie Inst., Publ. No. 385, p. 454, 1928. Sipho Brown, lUust. Conch. Gt. Brit. Ire., pi. 36, figs. 14-16, November, 1827, not Sipho Fabricius nor Morch. Cemaria (Leach) Swainson, Treat. Malac, p. 243, 1840, (? not Cemoria (Leach) Lowe, Zool. Journ., Vol. 3, p. 76, 1827, nor Risso, 1826). Diadora of .some authors, not Diodora Gray, 1821. Rimula of some authors, not of Risso, 1826. Type (by original designation), Patella noachina Linnaeus, figured by Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 229, pi. 27, figs. 69, 70, 1890, circumboreal, north Atlantic, also cold austral seas {fide Pilsbry). Shell small, conical, apex spirally recurved, persistent or absorbed in adult stage; fissure lanceo- late or oval, at front of or at summit of cone, provided within with a deck or shelly plate extending forward. In the typical section of Punclurella the apex is not absorbed by the perforation. In Section Fissurisepta Sequenza^ the apex is absorbed by the anal perforation. In section Cranopsis Adams, = the fissure is on the front slope instead of at the summit. Pimcturella galeata (Gould) Rimda galeata Gould, Proc. Boston Soc. Nat. Hist., Vol. 2, p. 159, 1846; Rept. U. S. Expl. Exped., Vol. 12, p. 369, 1852, Atlas Moll., pi. 31, figs. 476, 477, 1856. Pimcturella noachina Linne, var. galeata Gould, Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 230, pi. 42, figs. 62-65, 1890. Puncturella galeata Gould, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 341, 1903; Dall, Nautilus, Vol. 28, p. 64, 1914; U. S. Nat. Mus., BuU. 112, p. 185, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 240, pi. 93, fig. 3, 1927. Type locality: Puget Sound, Recent. Pleistocene: "Pliocene" [= Timms Point zone] of Deadman Island; lower San Pedro series of San Pedro, Los Angeles County, "one specimen" (Arnold). Recent: LTnalaska, Aleutian Islands, south to Santa Rosa Island, California (Dall, 1921). This species has two conical pits on each side of the septum within the apex of the shell. This unique character distinguishes it from the other Pacific coast species. Puncturella cucullata (Gould) Riinula galeata Gould, Proc. Boston Soc. Nat. Hist., Vol. 2, p. 159, 1846; Rept. U. S. Expl. Exped., Vol. 12, p. 369, 1852, Atlas Moll., pi. 31, fig. 475, 1856. Puncturella cucidlala Gould, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 261, 1888; Pilsbry, Tryon's Man. Conch., Ser. 1, Vol. 12, p. 232, pi. 42, figs. 72-75, pi. 63, figs. 38-39, 1890; DaU, Nautilus, Vol. 28, p. 63, 1914; U. S. Nat. Mus., Bull. 112, p. 185, 1921; Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 3, p. 241, pi. 93, fig. 4, 1927. 1 Annali del'Accademia degU Aspirant! Naturalisti, Napoli, Ser. 3, Vol. 2, p. S3, 1863; type, Fissurisepta papitloaa Sequenza, Sicilian Miocene, designated by Woodring, op. cit., p. 454, 1928. Reference taken from Woodring. g Ann Mag. Nat. Hist., Ser. 3, Vol. 5, p. 302, 1860; monotype, C. pelex A. Adams, Straits of Korea. 852 San Diego Society of Natural History [Memoirs Type locality: Puget Sound; Recent. Pliocene: Packard's Hill, Santa Barbara (Arnold). Pleistocene: "Pliocene" of Deadman Island; lower and upper San Pedro series of San Pedro, Los Angeles County (Arnold). Recent: Kodiak Island, Alaska, to La Paz, Lower California, Mexico (Dall, 1921). Puncturella cucullata (Gould) has sixteen prominent, widely separated, primary radiating ribs with subdued secondaiy ribs between. In Puncturella multistriata Dall the middle one of these secondary ribs is emphasized, giving the sculptural aspect of the shell a very different appearance. In Puncturella major Dall these middle secondary ribs are as strong as the primaries, giving the shell twice as many primary radiating ribs as cucullata. Mr. George Willett, of the Los Angeles Museum staff, has a series of Recent specimens of these species but they do not appear to intergrade and he is of the opinion that they are distinct species, at least in the Recent fauna. Pimcturella cucullata attains a larger .size in Alaskan waters than it does in southern California. Mr. Willett has Alaskan specimens that measure over 30 mm. in longer basal diameter whereas Catalina Island individuals rarely measure over 18 or 20 mm. In the north it occurs on rocks at the low tide line but in southern California it is obtained only by dredging. Puncturella delosi Arnold Puncturella delosi Arnold, Smithsonian Misc. Coll., Vol. 50, Pt. 4, p. 21, pi. 57, figs. 5a, 56, 1907. Type specimen: In the U. S. National Museum, No. 165,234. Type locality: Bath-house Beach, Santa Barbara; uppermost Pliocene. Pliocene: At the type locality (Arnold). This is a small very distinct species, measuring 1.8 mm. in altitude. It has numerous, prominent, closely spaced ribs. Puncturella cooperi Carpenter, a common dredged shell of southern California, does not seem to have been reported as a fossil. It probably occurs in the Pleistocene but may have been misidentified as one of the other species. Superfamily Ptenoglossa Family EPITONIIDAE Genus EPITONIUM Bolten, 1798 Scala Humphreys, Mus. Calonnianum, p. 23, 1797, declared invalid by the International Commission on Zoological Nomenclature. Epitonium Bolten, Mus. Boltenianum, Pt. 2, p. 91, 1798; Suter, Man. New Zealand Moll., p. 319, 1913; Dall, Proe. U. S. Nat. Mus., Vol. 53, p. 471, 1917; Woodring, Carnegie Inst., Publ. No. 385, p. 394, 1928. Cydostoma Lamarck, Mem. Soc. Hist. Nat. Paris, Vol. 1, p. 74, 1799, monotype Turbo scalaris Linnaeus. Scalaria Lamarck, Syst. Anim. s. Vert., p. 88, 1801, type (by monotypy), Scalaria conica Lamarck = Turbo scalaris Linnaeus. Type (by subsequent designation, Suter, 1913), Turbo scalaris Linnaeus (+ Scalaria pretiosa Lamarck), figured by Tryon, Man. Conch., Ser. 1, Vol. 9, p. 54, pi. 11, fig. 31, 1887, Indo-Pacific ; Recent. The typical subgenus of Epitonium embraces the species with rapidly enlarging and loosely coiled whorls, with a detached peristome and rather widely spaced, varix-hke axial ribs. Practically no attempt has been made by the present writers to revise the subgenera or species of Epitonium. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 853 Subgenus OPALIA H. and A. Adams, 1853 Opalia H. and A. Adams, Gen. Rec. Moll., Vol. 1, p. 223, November, 1853; de Boury, Monog. Scalidae Viv. Fos., Pt. 1, p. x.wi, 1886; Journ. de Conchyl., Vol. 57, p. 256, 1909; Cossmann, Ess. Paleo. Comp., Vol. 9, p. 77, 1912. Type (by subsequent designation, de Boury, 1886), Opalia australis (Lamarck), figured by Tryon, Man. Conch., Ser. 1, Vol. 9, p. 76, pi. 16, fig. 90, 1887, Australia ; Recent. The species of the subgenus Opalia are higher spired and more tightly coiled than those belonging to the typical subgenus of Epitonium. They also possess a basal carina. The type, E. australe, is remarkably similar to E. wroblewskyi (Morch). Epitonium (Opalia) wroblewskyi (Morch) Scalaria borealis Gould, Kept. U. S. Expl. Exped., Vol. 12, p. 207, 1852; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 76, pi. 16, fig. 89, 1887; not of Beck in Lyell, Rising of Sweden, p. 37, pi. 2, figs. 11, 12, 1839. Scala wrohleicskyi Morch, Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 8, p. 190, 1876. Opalia borealis Gould, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 255, 1888; Keep, West Coast Shells, p. 49, fig. 30, 1888, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 266, 1903. Epitoniimi (Opalia) borealis Gould, Berrj', Nautilus, Vol. 22, p. 38, 1908. ? Epitonium borealis Gould, Clark, Univ. Calif. Publ. Geol., Vol. 8, p. 422, 1915. Epitonium (Opalia) urobleu-skii Morch, Dall, U. S. Nat. Mus., Bull. 112, p. 113, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 51, pi. 31, fig. 5, 1927. Shell large, high spired, with few, low, sometimes very indistinct varices, the peristome coales- cing with the parietal wall. Type specimen: In the British Museum (Natural History). Type locality: Vancouver Island, British Columbia; Recent. ? Miocene: Lower San Pablo formation, upper Miocene of middle California ? (Clark). Pliocene: Excavation at Fifth and Hope Streets, Los Angeles (coll. by Charles M. Jay); Bath-house Beach, Santa Barbara, uppermost Pliocene (Berry). Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, "not rare" (T. S. Oldroyd) ; upper San Pedro series of San Pedro, "two specimens" (Arnold). Recent: Forrester Island, Alaska, to San Diego, California (DaU). This species is thinner shelled and slenderer than Epitonium varicostatum (Stearns) and its variety anomalum of the middle Pliocene of Southern California. Mature indi- viduals attain a length of 50 mm. or more, but the two specimens from the Fifth and Hope Streets deposit, Los Angeles (lower part of the upper Pliocene), are small and apparently immature. These latter show no signs of intergradation with varicostatum. Recent specimens of wroblewskyi often lack axial ribs on the body and penultimate whorls of adult individuals, but we have not seen any specimens with the axial sculpture entirely obsolete, analogous to variety anomalum of the mid-Pliocene species. Both Epitonium wroblewskyi and E. varicostatum have occasional crudely developed varices independent of the axial sculpture. Epitonium (Opalia) varicostatum (Stearns) Plate 24, Figure 20 Opalia varicostata Stearns, Proc. Acad. Nat. Sci. Phila. for 1875, p. 463, pi. 27, figs. 2-5, 1875; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 255, 1888; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 245, 1892; Stearns, Proc. U. S. Nat. Mus., Vol. 21, p. 298, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 267, 1903; Proc. U. S. Nat. Mus., Vol. 32, p. 527, 1907; Dall, Vol. 53, p. 473, 1917. Type specimen: In the U. S. National Museum. Type locality: Pacific Beach, San Diego; Phocene. 854 San Diego Society of Natural History [Memoirs Pliocene: Middle Pliocene of Pacific Beach (Stearns) and of the old San Diego well in Balboa Park (Cooper), San Diego; Temescal Canyon, near Santa Monica (Arnold, 1907), middle Pliocene. Epitonium varicostatum (Stearns) is a large, heavy-shelled species with typically ten or eleven varix-like ribs. It occurs, so far as known, only in the middle Pliocene of southern California, and seems to be characteristic. of the San Diego horizon. At Pacific Beach, San Diego, it grades into variety anomalum (Stearns) through gradual obso- lescence of the axial ribs. It is heavier and relatively shorter spired than Epitonium wroblewskyi (Morch), with which it does not appear to intergrade. Epitonium (Opalia) varicostatum (Stearns) variety anomalum (Stearns) Opalia anmnala Stearns, Proc. Acad. Nat. Sci. Phila. for 1875, p. 464, pi. 27, fig. 1, 1875; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 255, 1888; Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 245, 1892; Stearns, Proc. U. S. Nat. Mus., Vol. 21, p. 298, 1898; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 266, 1903; Dall, Proc. U. S. Nat. Mus., Vol. 53, p. 473, 1917. Type specimen: In the U. S. National Museum. Type locality: Pacific Beach, San Diego; Pliocene. Pliocene: San Diego well (Cooper); Pacific Beach, San Diego (Stearns). The variety anomalum (Stearns) lacks the axial ribs of the typical form of vari- costatum, except on the upper whorls of the spire where axial sculpture is often present. Intergradation occurs with the typical form at Pacific Beach, San Diego. As a variety, it is of little value. Epitonium (Opalia) rugiferum (Dall) Opalia rugifera Dall, Nautilus, \'ol. 22, p. 80, 1908. Epitonium (Opalia) rugiferum Dall, U. S. Geol. Surv., Prof. Paper 59, p. 52, pi. 3, fig. 10, April 2, 1909. Type specimen: In the U. S. National Museum. Type locality: Low Pass Canyon, Alaska Peninsula; "Miocene" ( = Pliocene ?). ? Miocene: Low Pass Canyon, Alaska Peninsula (Dall, 1908). ? Pliocene: Rock Creek, Columbia County, Oregon (Dall, 1909). This is a more evenly ribbed, shorter spired shell than E. varicostatum, which it otherwise closely resembles. The Rock Creek locality referred to above may be Miocene or even Oligocene in age. Epitonium (Opalia) tremperi (Bartsch)' from San Clemente Island, California, is a small species with numerous axial riblets and definite spiral threads quite unlike the species listed above. Subgenus STHENORYTIS Com-ad, 1868 Sthenorylis Conrad, Amer. Journ. Conch., Vol. 3, p. 259, April 2, 1868. Type (by monotypy), S. pachypleura Conrad, Journ. Acad. Nat. Sci. Phila., Ser. 2, Vol. 8, p. 565, 1862, figured in Amer. Journ. Conch., Vol. 3, pi. 21, fig. 4, 1868; Calvert Cliffs, Maryland; Miocene. Shell short with relatively very large body whorl; axial ribs thick, prominent, aciuninate at summit; aj)erture nearly romid, witli a thickened margm. > Proc. U. S. Nat. Mus., Vol. 70, Art. 11, p. 3, pi. 1. fig. 8, 1927. Volume I ] PlIOCBNE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 855 Epitonium (Sthenorytis) steamsii (Dall) Scala (Sthenorytis) steamsii Dall, Trans. Wagner Inst. Sci., Vol. 3, p. 245, pi. 21, fig. 4, December, 1892. Scala steamsii Dall, Stearns, Proc. U. S. Nat. Mus., Vol. 21, p. 298, 1898. Type specimen: In the U. S. National Museum, No. 106,904. Type locality: Pacific Beach, San Diego; Pliocene. Pliocene: Middle Pliocene of Pacific Beach, San Diego (DaO). This is a short, stout species, with strong axial ribs which taper posteriorly. Hanna and Hertlein^ have reported Epitonium (Sthenorytis) toroense (Dall) from the Pliocene beds of Monserrate Island, Gulf of California, Mexico, but this species is unknown in the Recent or fossil faunas of California. Subgenus DENTISCALA de Boury, 1886 Epitonium (Dentiscala) insculptum (Carpenter) Opalia {? crenatoides, var.) insculpta Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 660, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 17, p. 277, April, 1866. Opalia crenatoides var. (?) insculpta Carpenter, Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 255, 1888. Opalia crenatoides Carpenter, var. inscidpta Carpenter, Arnold, Mem. Calif. .4cad. Sci., Vol. 3, p. 267, 1903. Dentiscala insculpta Carpenter, Dall, Proc. U. S. Nat. Mus., Vol. 53, p. 473, 1917; Van Winkle, Bull. Amer. Paleon- tologj'. Vol. 8, p. 350 (or Bull. No. 36, p. 4), pi. 1, figs. 10, 11, 1921. Type specimens: In the collection at Cornell University (Van Winkle). Type locality: Near Santa Barbara; (Pliocene or) Pleistocene. Upper Pliocene: At the type locality (?). Pleistocene: Santa Barbara (Carpenter; Cooper) ; upper San Pedro series at Deadman Island, "rare" (Arnold). Epitonium insculptum (Carpenter) has thirteen to sixteen axial ribs and no spiral striae. Mr. A. M. Strong, who has made a careful study of the Pacific coast Epitoniidoe, says that the delicate spiral sculpture of such species as crenimarginatum would no doubt be lost during fossilization and that this factor must be considered in order to avoid redescribing living species in the fossil state. E. crenatoides is a Recent species with fewer varices than insculptum and appears to be quite distinct, though no doubt related. Subgenus NODISCALA de Boury, 1890 Nodiscala de Boury, Bull. See. Malac. Ital., Vol. 14, p. 12, 1890; Woodring, Carnegie Inst., Publ. No. 385, p. 404, 1928. Type (by original designation) Nodiscala bicarinata (Sowerby), figured by Tryon, Man. Conch., Ser. 1, Vol. 9, p. 82, pi. 17, fig. 28, 1887, Philippines; Recent. Shell small, slender, suture serrate; basal disk poorly developed; peristome complete, thick; sculpture consisting of obscure axial ribs and of spiral grooves; body whorl with two heavy spiral ridges, the lower one of which seems to limit the basal disk. (After Woodring.) Epitonium (Nodiscala) retiporosum (Carpenter) Opalia retiporosa Carpenter, Proc. Calif. Acad. Sci., Vol. 3, p. 222, 1864; Brit. Assn. Adv. Sci., Rept. for 1863, p. 660, 1864. Epitonivm (Opalia) retiporosa Carpenter, Moody, Univ. Calif. Publ. Geol., Vol. 10, p. 43, 1916. Nodiscala retiporosa Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 114, 1921. Epitonium (Nodiscala) retiporosum Carpenter, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 54, 1927. ' Proc. Calif. Acad. Sci., Ser. 4, Vol. 16, p. 143, 1927. 856 San Diego Society of Natural History [Memoirs Type specimen: In the California State Collection, No. 1,014, (University of Cali- fornia ?). Type locality: Catalina Island, California, in 40 fathoms. Pliocene: Excavation at Fourth Street between Hill and Broadway, Los Angeles, "rare" (Moody). Recent: Catalina Island, California, to the Gulf of California, Mexico (Dall, 1921). This species is not well known and it is difficult to recognize it from Carpenter's description. It was not figured by Carpenter nor by Tryon. Subgenus BOREOSCALA Kobelt, 1902 Shell usually white, with a basal disk bounded by a keel and both spiral and axial sculpture distinct. Arctoscala Dall, 1908,^ and Liroscala de Boury, 1909, are synonyms. The type of the subgenus is Epitonium greenlandicum (Perry). Epitonium (Boreoscala) condom Dall Arctoscala condoni Dall, Nautilus, Vol. 22, p. 80, 1908, nomen nudum with locality. Epitonium (Boreoscala) condoni DaU, U. S. Gaol. Surv., Prof. Paper 59, p. 53, pi. 3, figs. 1, 12, 1909. Type specimen: In the U. S. National Museum. Type locality: Eugene, Oregon; Oligocene. Oligocene: Eugene, Oregon, and Rock Creek, Columbia County, Oregon (Dall, 1909, as Miocene). Miocene: Low Pass, Alaska Peninsula (Dall, 1922). Epitonixun (Boreoscala) greenlandicum (Perry) Scalaria greenlandica Perry, Conch., pi. 28, fig. 8, 1811. ? Scalaria greenlandica Chemnitz, Tryon, Man. Conch., Ser. 1, Vol. 9, p. 76, pi. 16, fig. 91, 1887. Epitonium. (Boreoscala) greenlandicum Perry, Dall, Proc. U. S. Nat. Mus., Vol. 53, p. 472, 1917; Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 2, p. 55, 1927. Boreoscala greenlandica Perry, Dall, Journ. Washington Acad. Sci., Vol. 9, p. 2, 1919; U. S. Nat. Mus., Bull. 112, p. 114, 1921. Type locality: Greenland; Recent. Pliocene: Upper Pliocene of St. George Island, Pribilof Islands (Dall, 1919). Pleistocene: Pleistocene terraces of Japan (Dall, 1917). Recent: Arctic Ocean near Point Barrow and southward on the west to northern Japan and on the east to WrangeU, Alaska; circumboreal (DaU, 1921). ' Epitonium (Boreoscala) hemphilli (Dall) Scala hemphilli DaU, Proc. U. S. Nat. Mus., Vol. 1, p. 16, 1878; Cooper, 7th Ann. Kept. Calif. State Mineralogist, p. 263, 1888; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 264, 1903. Epitonium hemphilli DaU, Proc. U. S. Nat. Mus., Vol. 53, p. 472, 1917. Pliocene: San Diego weU, Balboa Park, San Diego (DaU, 1878). Pleistocene: Upper San Pedro series of San Pedro, "one immature specimen" (.Irnold). Subgenus ASPERISCALA de Boury, 1909 Asperiscala de Boury, Journ. de Conchyl., Vol. 57, p. 258, 1909. Type (by original designation), Scalaria bellastriata Carpenter, California; Recent. Shell without basal disk or carina; spiral sculpture present, axial lamellae somewhat spiny or angular at the shoulder. I Nautilus, Vol. 22, p. 80, December, 1908, type, by original designation, A. greenlandica (Perry). Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 857 Epitonium (Asperiscala) bellastriatum (Carpenter) Scalaria bellaslriata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 660, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 221, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 263, 1888. Scala bellastriala Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 263, pi. 9, fig. 17, 1903. Asperoscala bellastriata Carpenter, Dall, IT. S. Nat. Mus., Bull. 112, p. 114, 1921. Epitonivm (Asperoscala) bellastriatum Carpenter, Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Ft. 2, p. 55, 1927. Type specimen: In the California State Collection, No. 3936, (at the University of California ?). Type locality: Monterey, California; Recent. Pleistocene: Santa Barbara (Cooper) ; upper San Pedro series of San Pedro, "four" (Arnold) ; upper Pleistocene, of Santa Monica (Oldroyd Collection at Stanford University). Recent: Monterey to San Diego, California (Dall, 1921). Epitonium (Asperiscala) cedrosense Jordan and Hertlein Epitonium cedrosensis E. K. Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 446, pi. 3, fig. 3, July 22, 1926. Type specimen: At the CaUfornia Academy of Sciences, No. 2,116. Type locality: Bernstein's Abalone camp, Cedros Island, Lower California, Mexico; Phocene. Pliocene: Cedros Island and Turtle Bay, Lower California, Mexico (Jordan and Hertlein). Epitonium (Asperiscala) clarki T. S. Oldroyd Epitmium clarki T. S. Oldroyd, Nautilus, Vol. 34, p. 115, pi. 5, fig. 13, April, 1921. Type locality: Santa Monica, Los Angeles County; Pleistocene. Pleistocene: Upper Pleistocene of Santa Monica (T. S. Oldroyd). E. clarki Oldroyd is more slender than bellastriatum (Carpenter) and is apparently a distinct species. Epitonium (Asperiscala) dallasi E. K. Jordan and Hertlein Epitonium dallasi E. K. Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 447, pi. 30, fig. 2, July 22, 1926. Type specimen: At the California Academy of Sciences, No. 2,122. Type locality: One mile southeast of Turtle Bay, Lower California, Mexico: Phocene. Pliocene: At the tjrpe locaHty (Jordan and Hertlein). Subgenus NITIDISCALA de Boury, 1909 Nitidiscala de Boury, Journ. de Conchyl., Vol. 57, p. 257, 1909; Woodring, Carnegie Inst., Publ. No. 385, p. 400, 1928. "Nitidoscala" de Boury, of Dall, 1921, and other authors. Type (by original designation), Scalaria unifasciata Sowerby, Thes. Conch., Vol. 1, Scalaria, p. 98, pi. 33, fig. 68, ante April 11, 1844, also figured in Tryon, Man. Conch., Vol. 9, p. 71, pi. 14, fig. 55, 1887; West Indies; Recent. Shell small, rather slender, turreted, without a basal disk; axial sculpture consisting of strongly reflected retractive axial ribs fused across the sutures; spiral sculpture absent. 858 San Diego Society of Natural History [Memoirs Epitonium (Nitidiscala) acrostephanum Dall Epilonuim (Crisposcala) acrostephannni Dall, Proc. U. S. Nat. Mus., Vol. 34, p. 251, June 16, 1908. Nitidoscala acrostephanus Dall, U. S. Nat. Mus., Bull. 112, p. 116, 1921. Epitonium {Nitidoscala) acrostephanum Dall, T. S. Oltlroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Ft. 2, p. 65, 1927. Epitonium acrostephanum Dall, Jordan, Proc. Calif. Acad. Sci., Ser. 4, p. 245, 1926. Type specimen: In the U. S. National Museum, No. 110,638. Type locality: Monterey, California; Recent. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los .\ngeles County, "one specimen" (T. S. Oldroyd); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). This species is very close to Epitonium tabulatum (Dall), but the latter is a relatively broader shell. Epitonium (Nitidiscala) caamanoi (Dall and Bartsch) Scala caamanoi Dall and Bartsch, Canadian Greological Surv., Memoir 14N, p. 13, pi. 1, fig. 1, 1910. Nitidoscala caamanoi Dall and Bartsch, Dall, V. S. Nat. Mus., Bull. 112, p. 116, 1921. Epitonium {Nitidoscala) caamanoi Dall and Bartsch, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925; L S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 2, p. 62, pi. 31, fig. 3, 1927. Type specimen: In the Geological Survey Museum at Ottawa ? Type locality: Barkley Sound, Vancouver Island, British Columbia; Recent. Pleistocene: Lower San Pedro fauna of Nob Hill cut, Los Angeles County, "four specimens" (T. S. Oldroyd) . Recent: Vancouver Island, British Columbia, to San Pedro, California (Dall, 1921). Epitonium (Nitidiscala) continuatum T. S. Oldroyd Epitonium {Nitidoscala) continuatum T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, pp. 13, 35, pi. 2, fig. 10, January, 1925. Type specimen: In the U. S. National Museum, No. 352,383. Type locality: Nob Hill cut, San Pedro; Pleistocene. Pleistocene: At the type locality, "one specimen" (Oldroyd). Epitonium (? Nitidiscala) contrerasi E. K. Jordan and Hertlein Epitonium contrerasi E. K. Jordan and Hertlein, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 446, pi. 30, fig. 4, 1926. Type specimen: At the California Academy of Sciences, No. 2,121. Type locality: One mile southeast of Turtle Bay, Lower California, Mexico; Pliocene. Pliocene: At the type locality (Jordan and Hertlein). Epitonium (Nitidiscala) crebricostatum (Carpenter) Scalaria crebricostata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 660, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 222, 1864; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 263, 1888. Scala crebricostata Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 263, 1903. Nitidoscala crebricostata Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 115, 1921. Epitonium {Nitidoscala) crebricostatum Carpenter, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925; 1. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 61, 1927. Type specimen: In the California State Collection, No. 393, (at the University of California ?) . Type locality: Monterey, California; Recent. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 859 Pleistocene: Santa Barbara and San Pedro (Cooper); lower San Pedro series at San Pedro, also at Barlow's Ranch and the old irrigation ditch near Ventura; foot of Twenty-sixth Street, San Diego; upper San Pedro series at San Pedro and Deadman Island, Los Angeles County (Arnold) ; Nob Hill cut, San Pedro (T. S. Oldroyd). Recent: Vancouver Island, British Columbia, to the Gulf of California, Mexico (DaU, 1921). Epitonium (Nitidiscala) indianorum (Carpenter) Scalaria indianorum Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 660, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 31, January, 1865; Tryon, Man. Conch., Ser. 1, Vol. 9, p. 70, pi. 14, fig. 48, 1887; Cooper, 7th Ann. Rept. Calif. State Mineralogist, p. 263, 1888. Scala indianorum Carpenter, Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 210, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 264, pi. 5, fig. 4, 1903. Nitidoscala indianorum Carpenter, DaU, U. S. Nat. Mus., BuU. 112, p. 115, 1921. Epitonium indianorum Carpenter, I. S. Oldroyd, Univ. Washington, Publ. Puget Sound Biol. Sta., Vol. 4, p. 107, 1924. Epitonium (Nitidoscala) indianorum Carpenter, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 57, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Epitonium (Nitidiscala) indianorum (Carpenter), Strong, Trans. San Diego Soc. Nat. Hist., Vol. 6, p. 192, pi. 20, figs. 1, 2a, 26, 1930. Type specimen: In the U. S. National Museum, No. 15,521. Type locality: Neah Bay, Washington; Recent. Plioceiie: "Pico formation," near Ventura (Waterfall). Pleistocene: "Pliocene" of Deadman Island (Timms Point zone), lower Pleistocene; common in the lower and upper San Pedro series of San Pedro and vicinity (Arnold) ; lower San Pedro series of Nob Hill cut, San Pedro, "not rare" (T. S. Oldroyd); "Saugus formation," near Ventura (Waterfall). Recent: Forrester Island, Alaska, to Todos Santos Bay, Lower California, Me.xico (DaU, 1921). This species has been confused with others. A. M. Strong, conchologist of Los Angeles, has made a critical study of CaUfornia Recent Epitoniums, particularly Epi- tonium indianorum and its allies, and his results, part of which have just been published, clear up much of the confusion which has obscured the identity of some of the species herein catalogued. Epitonium (Nitidiscala) tinctum (Carpenter) Scalaria 1 var. tincla Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 660, 1864. Scalaria (f indianorum, var.) tincta Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 31, January, 1865. Scalaria suhcoronata Carpenter, Proc. Calif. Acad. Sci., Vol. 3, p. 221, 1866; Cooper, 7th Ann. Rept. Calif. State Min- eralogist, p. 263, 1888. "Scala hindsii Carpenter," Williamson, Proc. U. S. Nat. Mus., Vol. 15, p. 209, 1892; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 264, 1903; Keep, West Coast SheUs, p. 183, fig. 174, 1911, not of Carpenter, 1856, a Panama species. Not "Scala tincta Carpenter," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 265, pi. 5, fig. 3, 1903. Epitonium (Nitidoscala) fallanosum DaU, Proc. U. S. Nat. Mus., Vol. 53, p. 478, 1917; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 59, 1927. Nitidoscala suhcoronata Carpenter, DaU, U. S. Nat. Mus., BuU. 112, p. 115, 1921. Nitidoscala tincta Carpenter, DaU, op. cit., p. 115, 1921. Nitidoscala fallaciosa DaU, op. cit., p. 115, 1921. Epitonium (Nitidoscala) tinctum Carpenter, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 58, 1927. Epitonium fallaciosum. DaU, E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Epitonium tinctum Carpenter, E. K. Jordan, op. cit., p. 245, 1926. Epitonium (Nitidoscala) subcoronatum Carpenter, I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 58, 1927. Epitonium (Nitidiscala) tinctum (Carpenter), Strong, Trans. San Diego Soc. Nat. Hist., Vol. 6, p. 193, pi. 20, figs. 3, 4, 5a, 56, 1930. 860 San Diego Society of Natural History [Memoirs Type specimens: Of tinctum, in the U. S. National Museum, see discussion by Strong, 1930; of suhcoronatum, sometimes assumed to be in the Cahfornia State Collec- tion, University of Cahfornia, specimen No. 393a, probably in the U. S. National Museum, No. 13,8306, see discussion by Strong, 1930; of fallaciosum, in the U. S. National Museum. Type localities: Of tinctum, San Pedro, California, Recent; of suhcoronatum, Monte- rey, California, Recent; oi fallaciosum, California, Recent. Pliocene: San Diego well, Balboa Park, San Diego, middle Pliocene (Cooper, as subcoronata, probably also his record under tinctum). Pleistocene: Lower San Pedro series of Deadman Island and San Pedro (Arnold) as fallacioswn and crebri- costatum); lower San Pedro series of Nob Hill cut, San Pedro (T. S. Oldroyd, as suhcarinatum and tinctum); Santa Barbara and San Pedro (Cooper, as suhcoronatum, the Santa Barbara record possibly referring to the Santa Barbara horizon, upper Pliocene); Barlow's Ranch near Ventura (Arnold); upper San Pedro series of Deadman Island and San Pedro; Pacific Beach and foot of Twenty-sixth Street, San Diego (Arnold) ; upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan), us fallaciosum and tinctum). Recent: Vancouver Island, British Columbia, south to Lower California, probably to the Gulf of California. According to Strong (1930) E. tinctum differs from E. indianorum principally in its smaller size, more robust form, and the presence of the color band. Epitonium (Nitidiscala) cooperi Strong "Scala tincta Carpenter," Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 265, pi. 5, fig. 3, 1903, not of Carpenter, 1S64. "Epitonium hiiidsii Carpenter," Packard, Univ. Calif. Publ. Zool., Vol. 14, p. 319, pi. 36, figs. 14a, 146, 1918. "Epitonium fallaciosum Dall," Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926. Epitonium (Nitidiscala) cooperi Strong, Trans. San Diego Soc. Nat. Hist., Vol. 6, pp. 189, 194, pi. 20, figs. 6a, 66, 7, 8a, 86, 1930. Type specimen : In the collection of the San Diego Society of Natural History, No. 345. (Paratypes in the U. S. National Museum, Nos. 46,222 and 56,052.) Type locality: San Pedro, California; Recent. ? Pliocene: Pacific Beach and Russ School, San Diego (Arnold). Pleistocene: Barlow's Ranch, Ventura (Arnold), = Las Posas zone; rare in the lower San Pedro of San Pedro and vicinity; common in the upper San Pedro of San Pedro and vicinity, also at Pacific Beach and Twenty-sixth Street, San Diego (Arnold) ; Pleistocene, San Quintin Bay, Lower Cali- fornia (Jordan). Recent: San Francisco Bay, California (Packard in Strong), to the Gulf of California (?). This species has been well described and figured by Strong. Subgenus ACHILLA H. Adams, 1860 Acrilla H. Adams, Proc. Zool. Soc. London, Vol. 28, p. 241, 1860. Type (by original designation), Scalaria acuminata Sowerby, figured by Tryon, Man. Conch., Ser. 1, Vol. 9, p. 83, pi. 17, figs. 30, 35, 1887, Indo-Pacific ; Recent. Shell high spired, turritelUform, imperforate, with many whorls which are sculptured with numerous filiform ribs and a spiral ridge wliich suljcarinates the last whorl and may be slightly visible at the sutures; aperture oval, outer lip thin. Epitonium (Acrilla) atwoodi Dall Epitonium (Acrilla) atwoodi DaU, Nautilus, Vol. 22, pp. 80, 81, 1908. Type specimen: In the U. S. National Museum, No. 111,072. Type locality: About five miles south of the head of Port Moller, in the pass leading across Alaska Peninsula called Low Pass Canyon; Miocene. Miocene: At the type locality (Dall). Volume I ] PlIOCENE AND PLEISTOCENE MoLLXJSCA OF CALIFORNIA 861 Subgenus CATENOSCALA Dall, 1908 Catenoscala Dall, NautUus, Vol. 22, p. 80, December, 1908; U. S. Geol. Surv., Prof. Paper 59, p. 53, April 2, 1909. Type (by monotypy), Catenoscala oregonensis Dall, Eugene, Oregon, stated to be of Miocene age, probably middle Oligocene. Shell resembling that of Boreoscala but with the anterior portion of each whorl covered by a thick layer of enamel which obscures both axial and spiral sculpture. Epitonium (Catenoscala) oregonense Dall Catenoscala oregonensis DaU, Nautilus, Vol. 22, p. 80, December, 1908, nomen nudum, with locality. Epitonium (Catenoscala) oregonense DaU, U. S. Geol. Surv., Prof. Paper 59, p. 54, pi. 3, fig. 3, April 2, 1909. Type specimen: In the U. S. National Museum. Type locality: Eugene, Oregon, as Miocene, probably middle Oligocene. Oligocene: Eugene, Oregon, probably middle Oligocene; east side of Scow Bay, southeast of Port Townsend, Washington; near the west side of Oak Bay, Puget Sound (Dall, 1909, as Miocene, but probably all Oligocene); Low Pass Canyon, Alaska Peninsula (DaU, 1908, as Miocene, but probably of Oligocene age). Superfamily Gymnoglossa Family MELANELLIDAE As the west American Melanellidoe have been recently monographed by Bartsch,^ it is only necessary here to catalogue those species which come within the scope of the present paper. Most of the references and type designations have been taken from Bartsch. A comparison of some of the supposedly extinct Pleistocene species listed below with Recent species probably will show that all of them are conspecific with or only varietally distinct from their living representatives. Genus MELANELLA Bowdich, 1822 Melanella Bowdich, Elements of Concholog>-, Vol. 1, p. 27, 1822; Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 302, 1907. Type (by monotypjO, Melanella dufresnii Bowdich, op. cit., pi. 6, fig. 17, and expl. plate, 1822. Shell small, slender, white and pohshed, with a straight or curved spire of flat-sided whorls; apex acute ; aperture oval but produced to a point posteriorly, outer hp sometimes thickened inter- nally, inner lip reflected over bodj* whorl; not umbilicated ; operculum horny, spiral, with nucleus eccentric, or operculum absent. Through some over.sight, Bartsch (1917) placed the Melanellas with flexed or curved spires in the subgenus Balds Leach,- whereas the typical Melanella as figured by Bowdich has a distinctly curved spire. It is probable that the distinction between the curved and straight shells is of little taxonomic significance. Section IVIelanella, s. s. Melanellas with curved spires. 1 A Monograph of West American Melanellid MoUusks. Proc. U. S. Nat. Mus., Vol. 53, pp. 295-356, pis. 34-59, Aug. 13, 1917. ' Synop. Moll. Gt. Brit., p. 200, 1852, fide Bartsch, 1917. 862 San Diego Society of Natural History [Memoirs Melanella draconis Bartsch Melanella (Balcis) draconis Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 319, pi. 39, fig. 2, 1917. Pleistocene: Deadman Island, San Pedro Harbor, Los Angeles County (Bartsch). Melanella amoldi Bartsch Melanella (Balds) amoldi Bartsch, Proc. V. S. Nat. Mus., Vol. 53, p. 322, pi. 40, fig. 8, 1917. Pleistocene: Sand Rock, lower San Pedro series, Deadman Island, Los Angeles County (Bartsch). Melanella thersites (Carpenter) Eulima thersites Carpenter, Brit. Assn. Adv. Sci., Kept, for 1863, p. 659, 1864; Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 396, 1865. Eulima loivei Vanatta, Proc. Acad. Nat. Sci. Phila. for 1899, p. 254, pi. 11, figs. 9, 10, 1900. Eulima bistorta Vanatta, op. cil., p. 254, pi. 11, figs. 7, 8, 1900. Melanella (Balds) thersites Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 323, pi. 41, figs. 1, 2, 3, 1917. Melanella thersites Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 117, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925; E. K. Jordan, Proc. Cahf. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 70, pi. 47, fig. 2, 1927. Pldstocene: Lower San Pedro series of Nob Hill cut, Los Angeles (T. S. Oldroyd) ; upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey, California, to San Geronimo Island, Lower California, Mexico (Dall). Melanella berryi Bartsch Melanella (Balds) berryi Bartsch, Proc. V. S. Nat. Mus., Vol. 53, p. 326, pi. 42, fig. 3, 1917. Melanella berryi Bartsch, DaU, U. S. Nat. Mus., Bull. 112, p. 118, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 72, pi. 45, fig. 3, 1927. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey Bay to Catalina Island, California (Dall, 1921). Melanella lastra Bartsch Melanella (Balds) lastra Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 321, pi. 40, fig. 3, 1917. Melanella lastra Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 117, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 70, pi. 42, fig. 3, 1927. Pldstocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to Magdalena Bay, Lower California (Dall, 1921). Melanella perfalcata Bartsch Melanella (Balds) perfalcata Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 327, pi. 42, fig. 4, 1917. Melanella perfalcata Bartsch, T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 13, 1925. Pleistocene: Lower San Pedro series of Deadman Island (Bartsch); lower San Pedro series of Nob Hill cut (T. S. Oldroyd), Los Angeles County. Melanella falcata (Carpenter) Eulima falcala Carpenter, Proc. Zool. Soc. London for 1865, p. 280; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 268, pi. 9, fig. 15, 1903. Melanella (Balds) falcala Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 329, pi. 42, fig. 6, 1913. Type specimen: In the U. S. National Museum, No. 123. Type locality: Acapulco, Mexico; Recent. Pleistocene: Lower San Pedro series of Deadman Island and upper San Pedro series of San Pedro, one specimen from each (Arnold). Recent: West coast of Mexico. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 863 Melanella loleta E. K. Jordan Mdandla loleta E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 251, pi. 25, fig. 0, 1926. Pleistocene: Upper Pleistocene, San Qviintin Bay, Lower California, Mexico (Jordan). Section Eulima Risso, 1826 Eidima Risso, Hist. Nat. Eur. Merid., Vol. 4, p. 123, 1826. Melanellas with straight spires. Melanella micans (Carpenter) Eulima micans Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 659, 1864; Proc. Acad. Nat. Sci. Phila. for 1865, p. 63; Cooper, 7th Mn. Rept. Calif. State Mineralogist, p. 240, ISSS; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 269, pi. 9, fig. 12, 1903. Mdandla {Mdandla) micans Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 303, pi. 34, figs. 1-6, 1917. Melanella micans Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 118, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 74, 1927. Pleistocene: Santa Barbara to San Diego (Cooper) ; upper and lower San Pedro series of San Pedro region ; Barlow's Ranch, near Ventura; Spanish Bight, San Diego (Arnold); Santa Monica (collection of Dr. F. C. Clark); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Vancouver Island, British Columbia, to Point Abreojos, Lower California, Mexico (Dall, 1921). The large northern specimens have been named borealis Bartsch. Melanella rutila (Carpenter) Eulima rutila Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 659, 1864; Proc. Calif. Acad. Sci., Vol. 3, p. 221, 1865. Mdandla {Mdandla) rutila Carpenter, Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 306, pi. 35, figs. 2, 3, 6, 1917. Melanella rutila Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 118, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 75, pi. 46, figs. 2, 3, 6, 1927. Pleistocene: Deadman Island (Bartsch, as lower San Pedro series); Santa Monica, Santa Monica Canyon, San Pedro, Los Cerritos, and lumber yard at San Pedro, Los .■^.ngeles County; foot of Twenty-sixth Street, Spanish Bight, San Diego; San Quintin, Lower California, Mexico (Bartsch, as upper San Pedro series); San Quintin Bay, Lower California, Mexico (Jordan, as upper Pleistocene). Recent: Craig, Alaska (WiUett); Vancouver Island, British Columbia, to Magdalena Bay, Lower California, Mexico (Dall, 1921). This and the preceding species are the common Melanellas of California. Melanella monicensis Bartsch Mdandla (Mdandla) monicensis Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 309, pi. 36, fig. 2, 1917. Pleistocene: Santa Monica (Bartsch). Melanella necropolitana Bartsch Mdandla {Mdandla) necropolitana Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 309, jil. 36, fig. 3, 1917. Pleistocene: Sand Rock, lower San Pedro series, of Deadman Island, California (Bartsch). Melanella oldroydi Bartsch Mdandla {Mdandla) oldroydi Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 309, pi. 36, figs. 5, 6, 7, 1917. Melanella oldroydi Bartsch, Dall, U. S. Nat. Mus., BuU. 112, p. 118, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 245, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 76, pi. 41, figs. 5, 6, 7, 1927. Pleistocene: Lower San Pedro series of Deadman Island; upper San Pedro series of Santa Monica, Santa Monica Canyon, San Pedro, and lumber yard at San Pedro, Los Angeles County; Spanish Bight, San Diego; San Quintin, Lower California, Mexico (Bartsch). Recent: San Pedro to Point Abreojos, Lower California (Dall, 1921). Dall (1921) notes under this species: "Also Pliocene and Pleistocene." 864 San Diego Society of Natural History [ Memoirs Melanella hastata (Sowerby) Eulima hastata Sowerby, Proc. Zool. Soc. London for 1834, p. 6, 1834; A. Adams, in Sowerby, Thes. Conch., Vol. 2, p. 794, pi. 169, figs. 7, 8, 1854; Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 268, pi. 9, fig. 9, 1903. Melanella (Melanella) hastata Sowerby, Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 317, pi. 38, figs. 4, 6, 1917. Pleistocene: Lower San Pedro series at Deadman Island, one specimen; Barlow's Ranch, near Ventura; upper San Pedro series at San Pedro, four specimens; Spanish Bight, San Diego (Arnold). Recent: West coast of Mexico to Ecuador. "Eulima" smithi Van Winkle,' from the Molopophorus lincolnensis zone on the Cowlitz River, Washington, is not a Melanella. The species is minute, not well figured and its generic assignment must await further study of actual specimens. The name is a homonym of "Eulima" smMki Reagan^ and when its generic affiliation can be deter- mined it may be necessary to rename it.^ "Eulimella" gabbiana Anderson and Martin, from the Temblor horizon (lower middle Miocene) near Barker's Ranch, Kern County, is a typical Melanella. According to Hanna (Proc. Calif. Acad. Sci., Ser. 4, Vol. 13, p. 174, 1924) the cotypes of "Eulimella" ochsneri Anderson and Martin, from the Barker's Ranch Miocene, show that species to belong to Odostomia. Genus STROMBIFORMIS Da Costa, 1778 Stromhijm-mis Da Costa, Brit. Conch., p. 107, 1778; Iredale, Proc. INIalac. Soc. London, Vol. 11, p. 293, 1925; Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 339, 1917. Type (by subsequent designation, Iredale, 1915), Strombiformis glaber Da Costa. Melanellids with very narrow, elongated aperture, having the inner lip appressed to the attenu- ated basal portion of the preceding whorls; marked with one or more spiral color bands. (Bartsch.) Strombiformis raymondi (Rivers) Eulima raymondi Rivers, BuU. So. CaUf. Acad. Sci., Vol. 3, no. 5, p. 70, May, 1904; no. 6, plate (no number), figs. 2, June, 1904, misspelled "ramondi." Strombiformis riversi Bartsch, Proc. U. S. Nat. Mus., Vol. 53, p. 339, pi. 45, fig. 3, 1917. Type specimens: Of raymondi, in the River's collection ?; of riversi, No. 251,390, U. S. National Museum. Type localities: Of raymondi, "Pleistocene, Santa Monica Range, Cal."; of riversi, "in the upper San Pedro series, at Santa Monica Canyon, California." Pleistocene: Santa Monica Canyon, Santa Monica Range, Los Angeles County. Although we have not seen the type specimen of "Eulima" raymondi the figures and descriptions of it and of riversi Bartsch leave little doubt about their being the same 1 Univ. Wash. Publ. Geol.. Vol. 1. no. 2, p. 85, pi. 7, fig. 22, January, 1922. The type locality is "the Greece Ranch" and the age pre- sumed to be lower Uligocene but may be upper Eocene. * Trans. Kansas Acad. Sci., Vol. 22, p. 223, pi. 6, fig. 61, 1909. Dall studied Reagan's types and concluded "Eulima" smithi was a syno- nym of Strombiformis was}iingtoni (Reagan). * When this paper was in galley proof it was discovered that Van Winkle's Eulima smithi had been renamed "Pyramiddla (?) praecursor" by Hanna, Proc. Calif. Acad. Sci.. Ser. 4, Vol. 13, p. 178, 1924, which precludes the possibility of selecting better type material. Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CaLIFOHNIA 865 species. Strombiformis californica Bartsch' of the Recent southern California fauna is so similar that it should be considered a variety. Bartsch points out that Strombiformis townsendi,^ of the Gulf of California fauna, resembles californica. "Eulima" washingtoni Reagan (Trans. Kansas Acad. Sci., Vol. 22, p. 223, pi. 6, fig. 60, November, 1909) is a Strombiformis, according to Dall (Amer. Journ. Sci., Ser. 5, Vol. 4, p. 313, 1922), of which "Eulima" smithi Reagan {non Van Winkle) is a synonym. The age of Reagan's species is probably upper Miocene, not Pliocene as stated by Reagan. Family PYRAMIDELLIDAE The Pyramidellidce have been studied in detail by Dall and Bartsch, whose publica- tions' should be referred to for descriptions of the known genera, subgenera, sections, and species. Observations similar to those noted under the Melanellidoe are probably applicable here also. Many supposed species should be recognized as synonyms. Per- haps none of the Pleistocene species is extinct. The species of the Pyramidellidce have small, slender shells, characterized by proto- conchs coiled in oblique or reverse directions. Genus PYRAMIDELLA Lamarck, 1799 Subgenus LONGCHAEUS Morch, 1875 Pyramidella (Longchaeus) mexicana (Dall and Bartsch in Arnold) Turhonilla mexicana Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 280, 1903. Pyramidella conica Adams, var. variegata Carpenter, Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 280, 1903, not of Carpenter, 1864. Pyramidella (Lmgchseus) mexicana Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 23, pi. 1, fig. 12, 1909; I. S. Old- royd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 87, 1927. Longchams mexicanvs Dall and Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 120, 1921. Pleistocene: Upper San Pedro series of San Pedro, "rare" (Arnold, as P. conica, var. variegata Carpenter, "probably" Turhonilla mexicana Dall and Bartsch). Recent: San Diego, California, to Scammon's Lagoon, Lower California, Me.xico (DaU). Genus TURBONILLA Risso, 1826 Subgenus TURBONILLA, s. s. Shell often small and slender; without spiral sculpture but with prominent axial ribs extending from summits of whorls to umbiHcal region; columella straight or slightly twisted. 1 Proc. U. S. Nat. Mus., Vol. 53, p. 340, pi. 45, fig. 5, 1917. = Bartsch, op. cit., p. 340, pi. 46, fig. 4, 1917. ' Dall and Bartsch: "Synopsis of the Genera, Subgenera, and Sections of the Family Pyramidellidse," Proc. Biol. Soc. Washington, Vol, 17, pp. 1-16, February 5, 1904. Dall and Bartsch: "Notes on Japanese, Indo-Pacific, and American Pyramidellidje," Proc. U. S. Nat. Mus., Vol. 33, pp. 321-369, pis. 17-26, 1906. Dall and Bartsch: "The Pyramidellid MoUusks of the Oregonian Faunal Area," Proc. U. S. Nat. Mus., Vol. 33, pp. 491-534, pis. 44-48, December 31, 1907. Dall and Bartsch: "A Monograph of West American Pyramidellid Mollusks," U. S. Nat. Mus., Bull. 68, 258 pp., 30 ppl., 1909 Bartsch: "Additions to the West American Pyramidellid MoUxisk Fauna, with Descriptions of New Species," Proc. U. S. Nat. Mus., Vol. 42, pp. 261-289, pis. 35-38, May 17, 1912. 866 San Diego Society of Natural History [Memoirs Turbonilla (Turbonilla) gilli Dall and Bartsch Turbonilla {Turbonilla) gilli Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, pp. 493, 494, pi. 14, fig. 5, 1907; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 24.5, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 87, pi. 49, fig. 8, 1927. Turbonilla gilli Dall and Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 120, 1921. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Me.xico (Jordan). Recent: Catalina Island to San Diego, California. Subgenus CHEMNITZIA d'Orbigny, 1839 Shell usually small and slender; spiral sculpture absent; axial sculpture consisting of prominent axial ribs which fuse or terminate at the lower periphery ; intercostal spaces deep, terminatmg above or at basal periphery; base smooth; columella straight. Turbonilla (Chemnitzia) aep5mota Dall and Bartsch Turbonilla {Chemnitzia) s>pynoia Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 35, pi. 2, figs. 10, 10a, 1909; Dall, U. S. Nat. Mus., Bull. 112, p. 121, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 14, 1924; I. S. Oldroyd, Stanford Univ. Publ, Geol, Vol, 2, Pt. 2, p, 90, pi. 49, figs. 10, 10a, 1917. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, Los Angeles County (T. S. Oldroyd). Recent: San Pedro, California, to San Martin Island, Lower California, Mexico (Dall). Turbomlla (Chemnitzia) muricata (Carpenter) Chemnitzia muricata Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 428, 1855-7; Brit. Assn. Adv. Sci,, Rept. for 1856, pp. 260, 334, 1857. Turbonilla {Strioturbonilla) muricata Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad, Sci,, Vol, 3, p. 270, 1903. Turbonilla {Chemnitzia) muricata Carpenter, DaU and Bartsch, U. S. Nat, Mus., Bull. 68, p. 36, pi. 2, fig. 9, 1909. Pleistocene: Lower San Pedro series of San Pedro and Deadman Island, "rare"; upper San Pedro series of San Pedro and Los Cerritos, "rather common" (Arnold), Recent: Mazatlan, Mexico (Carpenter). Turbonilla (Chemnitzia) paramoea Dall and Bartsch Chemnitzia similis C, B, Adams, Ann, Lye. Nat. Hist. New York, Vol. 5, p. 392, 1852, name preoccupied ? Turbonilla {Strioturbonilla) similis C. B. Adams, Dall and Bartsch in Arnold, Mem. Calif. Acad, Sci., Vol, 3, p. 270, 1903. Turbonilla {Chemnitzia) -paramoea Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 37, pi. 2, figs. 4, 4a, 1909. Pleistocene: Lower San Pedro series at Deadman Island and San Pedro, "rare"; upper San Pedro series at San Pedro and Los Cerritos, "common" (Arnold). Recent: Panama (Adams). Subgenus STRIOTURBONILLA Sacco, 1892 Shell with fine, close spiral striations on the spire and base.^ Turbonilla (Striotiurbonilla) buttoni Dall and Bartsch Turbonilla {Strioturbonilla) buttoni Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 43, pi. 3, figs. 4, 4a, 1909; Dall, Bull. 112, p. 121, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 95, 1927. Turbonilla buttoni DaU and Bartsch, E. P. and E. M. Chace, Lorquinia, Vol. 2, p. 42, 1919. Pleistocene: Point Firmin chiton bed, Los Angeles County (Chace). Recent: Santa Rosa Island, California, to Point Abreojos, Lower California, Mexico (Dall). ' Mr. George Willett, of the Los Angeles Museum, points out that many specimens of some of the California species assigned to Strio- turbonilla do not show any evidence of spiral striations. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 867 Turbonilla (Strioturbonilla) asser Dall and Bartsch Turbonilla (Strioturbonilla) asser DaU and Bartsch, U. S. Nat. Mus., Bull. 68, p. 45, pi. 3, figs. 1, la, 1909; Bull. 112, p. 122, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 6.5, Art. 22, p. 14, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. GeoL, Vol. 2, Pt. 2, p. 97, 1927. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, Los Angeles County (T. S. Oldroyd) ; upper Pleistocene of San Quintin Bay, Lower California, Me.xico (Jordan). Recent: Redondo Beach to San Diego, California (Dall). Turbonilla (Strioturbonilla) stylina (Carpenter) Chemnitzia (f torguata var.) stylina Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 396, 1865. Turbonilla stylina Carpenter, Newcombe, Nautilus, Vol. 10, pp. 17, 20, 1896. Turbonilla (Strioturhonilla) torguata, variety stylina Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 272, pi. 1, figs. 10, lOo, 1903. Turbmiilla (Strioturhmiilla) stylina Carpenter, Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 48, pi. 3, figs. 7, 7a, 1909; Dall, Bull. 112, p. 122, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; L S. Oldroyd, Stanford Univ. Publ. Geol., ^'ol. 2, Pt. 2, p. 100, 1927. Pleistocene: San Pedro and San Diego, "abundant" (Arnold); upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Monterey to the Coronado Islands, off San Diego, California. Turbonilla (Strioturbonilla) torquata (Gould) Chemnitzia torguata Gould, Boston Journ. Nat. Hist., Vol. 4, p. 384, 1852. Turbonilla torguata Gould, Baker, Nautilus, Vol. 16, p. 41, 1902. Turbonilla {St7i.oturbo7iilla) torguata Gould, Dall and Bartsch, LT. S. Nat. Mus., Bull. 68, p. 47, pi. 4, figs. 15, 15a, 1909; not T. (S.) torguata Gould, of Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 271, pi. 2, figs. 4, 4a, 1903, = T. (S.) ralphi Dall and Bartsch, 1909. Recent: Point Firmin, Los Angeles County, California, to San Martin Island, Lower California, Mexico (Baker). Turbonilla (Strioturbonilla) ralphi Dall and Bartsch "Turbonilla {Strioturbonilla) torguata Gould," Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 271, pi. 2, figs. 4, 4a, 1903, not Chemnitzia torguata Gould, 1852. Turbonilla {Strioturbonilla) ralphi Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 47, 1909. Pleistocene: San Pedro and San Diego, abimdant (Arnold). Turbonilla (Strioturbonilla) attrita Dall and Bartsch Turbonilla {Strioturbonilla) attrita Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 46, pi. 4, figs. 11, 11a, 1909; Dall, Bull. 112, p. 122, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 97, 1927. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro to San Diego, California (Dall). Turbonilla (Strioturbonilla) simpsoni Dall and Bartsch Turbonilla (Strioturbonilla) simpsoni Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 49, pi. 3, figs. 6, 6a, 1909; Dall' Bull. 112, p. 122, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 101, 1927. Turbonilla (Strioturbonilla) ef. simpsoni Dall and Bartsch, Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. ? Pliocene: Pico formation near Ventura (listed doubtfully by Waterfall). Recent: Off Redondo, Los Angeles County, to San Diego, California (Dall). 868 San Diego Society of Natural History [Memoirs Turbonilla (Strioturbonilla) carpenter! Dall and Bartsch Turbonilla (Slriolurbonilla) carpenteri Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 49, pi. 3, figs. 9, 9n, 1909; Dall, Bull. 112, p. 122, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 100, 1927; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pleistocene: "Saugus" formation near Ventura (Waterfall). Recent: San Pedro, California (Dall). Turbonilla (Striottirbonilla) aresta Dall and Bartsch Turhonilla {Strioturbonilla) aresta Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 54, pi. 4, figs. 5, 5a, 1909; Dall, Bull. 112, p. 123, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 14, 1925; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 105, 1927. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro, "one specimen" (T. S. Oldroyd). Recent: Santa Rosa Island to San Diego, California (Dall). Turbonilla (Strioturbonilla) steamsii Dall and Bartsch in Arnold Turbonilla (Strioturbonilla.) steamsii Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 271, pi. 2, figs. 5, 5a, 1903. Pleistocene: San Pedro and San Diego, abundant (Arnold). Recent: Gulf of California, Mexico. Turbonilla (Striotiu-bonilla) pecora T. S. Oldroyd Turbonilla pecora T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 24, pi. 1, fig. 6, 1925. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los Angeles County (Oldroyd). Subgenus PYRGOLAMPROS Sacco, 1892 Turbonillas with low, broad, rounded vertical ribs, which almost always disappear as they pass over the periphery and base of the last whorl, and many very fine, faint, wavy spiral striations; surface covered by a thin epidermis; columella usually somewhat flexuose. (Dall and Bartsch, 1909.) Tiu-bonilla (Pyrgolampros) valdezi Dall and Bartsch "Turbonilla (Pyrgolampros) gibbosa Carpenter," Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 279, pi. 1, figs. 2, 2a, 1903, not Chenmitzia gibbosa Carpenter, Cat. Reigen Coll. Mazatlan MoU. Brit. Mus., p. 430, 1857. Turbonilla (Pyrgolampros) valdezi Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 502, pi. 44, figs. 3, 3a, 1907; U. S. Nat. Mus., Bull. 68, p. 62, pi. 6, fig. 8, 1909; Dall, Bull. 112, p. 123, 1921. Pleistocene: Lower San Pedro series of Deadman Island (Arnold). Recent: Barkley Sound, Vancouver Island, British Columbia, to Monterey, California (Dall). Turbonilla (Pyrgolampros) lowei Dall and Bartsch in Arnold Turbonilla (Pyrgolampros) lowei Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 278, pi. 1, figs. 5, 5a, 1903; U. S. Nat. Mus., Bull. 68, p. 64, pi. 6, figs. 11, 11a, 1909; Dall, BuU. 112, p. 123, 1921. Pleistocene: San Pedro and San Diego (Arnold). Recent: San Pedro to San Diego, California (Dall). Turbonilla (Pyrgolampros) gouldi Dall and Bartsch Turbonilla (Pyrgolampros) gouldi Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 66, pi. 6, figs. 1, la, 1909; Dall, Bull. 112, p. 123, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Santa Rosa Island to San Diego, California. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 869 Turbonilla (Pyrgolampros) aurantia (Carpenter) Chemnitzia (? var.) aurantia Carpenter, Journ. de Conchyl., Vol. 12, p. 147, 1S65. Turbonilla (Lancea) aurantia Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 272, 1903. Turbonilla (Pyrgolampros) aurantia Carpenter, Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 502, pi. 45, fig. 5, 1907; U. S. Nat. Mus., Bull. 68, p. 66, pi. 6, fig. 4, 1909; Dall, Bull. 112, p. 123, 1921. Pleistocene: Lower and upper San Pedro series of San Pedro region (Arnold). Recent: Departure Bay, Victoria, British Columbia, and Puget Sound (Dall). Turbonilla (Pyrgolampros) pedroana Dall and Bartsch in Arnold Turbonilla {Pyrgolampros) lowci, var. ptdroana Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 279, pi. 2, figs. 3, 3a, 1903. Turbonilla (Pyrgolampros) pedroana Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 67, pi. 6, figs. 12, 12a, 1909; Dall, Bull. 112, p. 123, 1921. Pleistocene: Spanish Bight, San Diego (Arnold). Recent: Victoria, British Columbia, to San Diego, California (Dall). Turbonilla (Pyrgolampros) adleri Dall and Bartsch in Arnold Turbonilla (Pyrgolampros) adleri Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 280, pi. 1, fig. 9, 1903. Turbonilla (Pyrgolampros) alderi Dall and Bartsch, Schuchert, U. S. Nat. Mus., Bull. 53, Pt. 1, p. 673, 1905, catalogue entry only. Pleistocene: Deadman Island, Los Angeles County. Turbonilla (Pyrgolampros) amara Bartsch Turboyiilla (Pyrgolampros) amara Bartsch, Proc. Biol. Soc. Wash., Vol. 31, p. 81, 1918. Pleistocene: Lower San Pedro series of Deadman Island. Los Angeles County. Turbonilla (Pyrgolampros) amoldi Dall and Bartsch in Arnold Turbonilla (Pyrgolampros) amoldi Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 279, pi. 1, fig. 7, 1903. Pleistocene: Lower San Pedro series of Deadman Island, Los Angeles County. Turbonilla (Pyrgolampros) idae T. S. Oldroyd Plate 24, Figure 23 Turbonilla (Pyrgolampros) ids' T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 26, pi. 1, fig. 9, 1925. Pleistocene: Lower San Pedro fauna of Nob Hill cut, San Pedro (T. S. Oldroyd); S. D. S. N. H. localities 247 and 249, Kalorama Canyon, north of Ventura, and locality 233, north of Arroyo Santa Rosa, Ventura County (identifications by T. S. Oldroyd). Turbonilla (Pyrgolampros) collisella T. S. Oldroyd Turbonilla (Pyrgolampros) collisella T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 25, jil. 1, fig. 11, 1925. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro. Turbonilla (Pyrgolampros) gloriosa Bartsch Turbonilla (Pyrgolampros) gloriosa Bartsch, Proc. U. S. Nat. Mus., Vol. 42, p. 268, pi. 35, fig. 9, 1912; Dall, U. S. Nat. Mus., Bull. 112, p. 124, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: Off San Diego, California, in 12 fathoms (Bartsch). 870 San Diego Society of Natural History [ Memoirs Turbonilla (Pyrgolampros) hannibali Bartsch Tiirhomlla (Pyrgolaiupron) hannibali Bartsch, Proc. U. S. Nat. Mils., Vol. 52, p. 645, pi. 43, fig. 7, 1917. Pliocene: Elk River beds at the mouth of Elk River, Port Orford, Oregon, upper Pliocene (or lower Pleisto- cene). Turbonilla (Pyrgolampros) hemphilli Bartsch Tnrbonilla {Pyrgolampros) hemphilli Bartsch, Proc. U. S. Nat. Mus., Vol. 52, p. 646, pi. 44, fig. 8, 1917. Pliocene: San Diego well, Balboa Park, San Diego, at depth of 140 feet. Turbonilla (Pyrgolampros) rinella Dall and Bartsch Turbonilla {Pyrgolampros) rinella Dall and Bartsch, Mem. Canadian Geol. Surv., Vol. 14, p. 14, pi. 1, fig. 2, 1910; Dall, U. S. Nat. Mus., Bull. 112, p. 124, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 14, 1925; I. 8. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 120, 1927. Pleistocene: Lower San Pedro series of Nob HiU cut, San Pedro, Los Angeles County (T. S. Oldroyd). Recent: Barkley Sound, Vancouver Island, British Columbia (Dall). Subgenus PYRGISCUS Philippi, 1841 Turbonillas having prominent axial ribs and deeply incised spiral lines but no varices or internal lirations on the outer lip; columella usually somewhat flexuous. (Dall and Bartsch.) Turbonilla (Pyrgiscus) vexativa DaU and Bartsch TurboniUa (Pyrgiscus) vexativa Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 77, pi. 7, fig. 11, 1909; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pyrgiscus vexalivns Dall and Bartsch, Dall, U. S. Nat. Mus., Bull. 112, p. 125, 1921. Pleistocene: San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro to San Diego, California (Dall). Turbonilla (Pyrgiscus) antestriata Dall and Bartsch Turbonilla {Pyrgiscus) antestriata Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 506, pi. 45, figs. 4, 4a, 1907; U. S. Nat. Mus., Bull. 68, p. 87, pi. 8, figs. 5, 5a, 1909; Dall, Bull. 112, p. 126, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Esteros Bay to San Diego, California (Dall). Turbonilla (Pyrgiscus) almo Dall and Bartsch Turbmiilla {Pyrgiscus) almo Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 95, pi. 9, figs. 8, 8a, 1909; Dall, Bull. 112, p. 126, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Diego, California. Turbonilla (Pyrgiscus) tenuicula (Gould) Chemnitzia tenuicula Gould, Boston Journ. Nat. Hist., Vol. 6, p. 3S3, pi. 14, fig. 15, 1853. Che7nnitzia terebralis Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 432, 1856. Chemnitzia unifasciala Carpenter, op. cit., p. 433, 1856. Chemnitzia ? var. stibcuspidaia Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 659, 1864. Cliemnitzia crebrifilata Carpenter, Brit. Assn. Adv. Sci., Rept. for 1863, p. 659, 1864. Turbonilla (Pyrgiscus) tenuiada Gould, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 275, pi. 2, figs. 7, 7(1, 1903; Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 92, pi. 8, figs. 3, 7, 7a, 12, 12a, 14, 14a, 1909; Dall, Bull. 112, p. 126, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 14, 1925. VoLTOiE 1 1 Pliocene and Pleistocene Mollusca of California 871 Turhonilla (Pyrgiscus) crebrifilata Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 276, pi. 2, figs. 6, 6a, 1903. Turhonilla (Pyrgiscus) subcuspidala Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., ^'ol. 3, p. 277, pi. 2, figs. 2, 2a, 1903. Pleistocene: San Pedro and San Diego regions. Recent: Monterey, California, to Point Abreojos, Lower California, Mexico (Dall), and south ? Turhonilla (Pyrgiscus) auricoma Dall and Bartsch in Arnold Turbonilla (Pyrgiscus) auricoma Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 274, pi. 1 ,figs. 4, 4a, 1903; U. S. Nat. Mus., Bull. 68, p. 100, pi. 9, figs. 5, oo, 1909; Dall, Bull. 112, p. 126, 1921. Pleistocene: San Diego. Recent: San Pedro, California, to Scammons Lagoon, Lower California, Mexico (Dall). Turhonilla (Pyrgiscus) latifunda Dall and Bartsch in Arnold Turbonilla (Pyrgiscus) latifunda Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 275, pi. 3, figs. 5, 5a, 1903. Pleistocene: San Pedro and Deadman Island, Los Angeles County. Turhonilla (Pyrgiscus) himerta T. S. Oldroyd Turbonilla (Pyrgiscus) himerta T. S. Oldroyd, Proc. U. S. Xat. Mus., Vol. 65, Art. 22, pp. 14, 27, pi. 1, fig. 1, 1925. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los Angeles County. Turbonilla (Pyrgiscus) hertleini E. K. Jordan Turbonilla (Pyrgiscus) hertleini E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 252, pi. 25, fig. 6, 1926. Pleistocene: Upper Pleistocene, San Quintin, Lower California, Mexico. Subgenus MORMULA A. Adams, 1864 Turbonillas having axial ribs and deeply incised spiral lines; also irregularly disposed varices on the outer surface, which usually mark internal lirations on the outer lip, or mternal lirations of the outer lip only; sculpture never nodulose. (Dall and Bartsch.) Turbonilla (Mormula) catalinensis Dall and Bartsch Turbonilla (Mormula) catalinensis Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 113, pi. 11, figs. 10, 10a, 1909; DaU, Bull. 112, p. 127, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: Catalina Island, California (Dall). This species appears to be very closely related to Turbonilla regina Dall and Bartsch. Turbonilla (Mormula) tridentata (Carpenter) Chemnitzia tridentata Carpenter, Journ. de Conchyl., \o\. 13, p. 147, 1865. Turbonilla (Lancea) tridentata Carpenter, DaU and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 273, pi. 2, figs. 1, la, 1903. Turbonilla (Mormula) tridentata Carpenter, Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 511, pi. 45, fig. 9, 1907; U. S. Nat. Mus., Bull. 68, p. 114, pi. II, figs. 12, 12a, 1909; DaU, Bull. 112, p. 127, 1921. Turbonilla (Mormula) amhusta Dall and Bartsch, Bull. 68, U. S. Nat. Mus., p. 115, pi. 11, fig. 13, 1909; Dall, BuU. 112, p. 127, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 148, pi. 56, fig. 13, 1927. Pleistocene: San Pedro region, Los -\ngeles County. Recent: Monterey to San Diego, California. I 872 San Diego Society of Natural History [Memoirs Mr. George Willett has called attention to a series of specimens of tridentata in his collection which shows complete intergradation in number of axial ribs and spiral stria- tions with ambusta Dall and Bartsch, which name, therefore, must fall into synonymy. Turhonilla regina aiid cataUnensis, both of Dall and Bartsch, are similar but appear to be consistently larger. Turhonilla lordi E. A. Smith is a similar large northern shell, but it has distinct color bands when fresh. Turbonilla (Mormula) pentalopha Dall and Bartsch in Arnold Turhonilla (Lancea) pentalopha Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 274, pi. 1, figs. 1, la, 1903. Turbonilla (Mormula) pentalopha Dall and Bartsch, U. S. Nat. Mils., Bull. 68, p. 117, pi. 11, figs. 3, 3o, 1909; Dall, Bull. 112, p. 127, 1921. Pleistocene: Deadman Island, San Pedro, Los Angeles County. Recent: San Pedro, California, to Todos Santos Bay, Lower California, Mexico (Dall). Turbonilla (Mormula) epiphanea T. S. Oldroyd Turbonilla (Mormvla) epiphanea T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 28, pi. 1, fig. 12, 1925. Pleistocene: Lower San Pedro series at Nob Hill cut, San Pedro, Los Angeles County (Oldroyd). Subgenus BARTSCHELLA Iredale, 1916 Turbonilla (Bartschella) laminata (Carpenter) Dunkeria laminata Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 396, 1865. Turbonilla {Pyrgisculus) laminata Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 277, pi. 2, figs. 8, 8o, 1903. Turbonilla {Dunkeria.) laminata Carpenter, Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 122, pi. 12, figs. 16, 16a, 1909. Turhonilla (Bartschella) laminata Carpenter, Dall, U. S. Nat. Mus., Bull. 112, p. 127, 1921; T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65; Art. 22, p. 14, 1925; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro (Oldroyd), and of San Pedro Bluffs and Deadman Island; Barlow's Ranch, near Ventura; upper San Pedro series of the lumber yard at San Pedro and of Los Cerritos, Los Angeles County (Arnold) ; upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to Point Abreojos, Lower California, Mexico (Dall). Genus ODOSTOMIA Fleming, 1817 Odostomia Fleming, Edinburgh Encycl., Vol. 7, Pt. 1, p. 76, 1817. Shell with sinistral apex, usually short, few whorled, subconic or ovate, with a single columellar fold, which varies in strength and sometimes is not apparent at the aperture; sculpture varying from smooth to lamellar ribs and spiral keels. (Dall and Bartsch, 1909.) Subgenus CHRYSALLIDA Carpenter, 1856 Chrysallida Carpenter, Cat. Reigen Coll. Mazatlan Moll. Brit. Mus., p. 416, 1856. Odostomias with strong axial ribs crossed by equally strong spiral keels between the sutures, the intersection of these two elements forming nodules. The axial ribs pass only faintly over the base, while the spiral sculpture remains quite prominent. (Dall and Bartsch.) Odostomia (Chrysallida) diegensis Dall and Bartsch in Arnold Odostomia (Chrysallida) diegensis Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 284, pi. 1, fig. 8, 1903. Pleistocene: San Diego. Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 873 Odostomia (Chrysallida) gomphina T. S. Oldroyd Odostomia (Chrysallida) gomphina T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 29, pi. 1, fig. 3, 1925. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los Angeles County. Odostomia (Chrysallida) scelera T. S. Oldroyd Odoskmia {Chrysallida) scelera T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 30, pi. 1, fig. 4, 1925. Pleistocene: Lower San Pedro fauna of Nob HiU cut, San Pedro. Odostomia (Chrysallida) dallasi E. K. Jordan Odostomia (Chrysallida) dallasi E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 253, pi. 25, fig. 4, 1926. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico. Subgenus IVIDELLA Dall and Bartsch, 1909 Odostomias with lamellar spiral ridges and equally strong lamellar axial ribs, both of which ornament spire and base. (Dall and Bartsch.) Odostomia (Ividella) pedroana Dall and Bartsch Odostomia (hndella) -pedroana Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 172, pi. 19, figs. 8, 8a, 1909; Dall, Bull. 112, p. 130, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Odostomia (Ividella) navisa Dall and Bartsch variety delmontensis Dall and Bartsch Odostomia (Ividia) navisa delmontensis Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 518, pi. 46, figs. 3, 3a, 1907. Odostomia (Imdella) navisa delmontensis Dall and Bartsch, Bull. 68, p. 174, pi. 18, figs. 10, 10a, 1909; Dall, Bull. 112, p. 130, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: San Quintin Bay, Lower California, Mexico. Recent: Off Del Monte, Monterey Bay, California. Subgenus IVARA Dall and Bartsch in Arnold, 1903 Ivara Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 285, 1903, monotype 0. terricula = 0. turricula Carpenter MS. in Dall and Bartsch in Arnold; Proc. Biol. Soc. Wash., Vol. 17, p. 11, 1904. Odostomias having feebly developed axial ribs, which are usually only indicated near the sum- mits of the whorls; spiral sculpture consisting of many subequally-spaced fine lirations; summits of the whorls strongly tabulated. (Dall and Bartsch.) Odostomia (Ivara) turricula Carpenter MS. in Dall and Bartsch in Arnold "Odostomia (Ivara) terricula (Carpenter)" Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 285, pi. 4, fig. 14, 1903, misprint for turricula, assigned to Carpenter, possibly through error. Odostomia (Ivara) turricula Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 179, pi. 19, fig. 9, 1909. "Ivara terricula DaU and Bartsch," DaU, U. S. Nat. Mus., Bull. 112, p. 130, 1921. Pleistocene: Lower San Pedro series of Deadman Island, "one specimen" (Arnold). Recent: Monterey, California, to Point Abreojos, Lower California. Odostomia (Ivara) amava T. S. Oldroyd Odostomia (Ivara) amava T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 29, pi. 1, fig. 7, 1925. Pleistocene: Nob Hill cut, San Pedro. 874 San Diego Society of Natural History [Memoirs Subgenus lOLAEA A. Adams, 1867 lolxa A. Adams, Proc. Zool. Soc. London for 1867, p. 310; Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 181, 1909. Shell umbilicated, marked by spiral cords and axial riblets, the axial riblets crossing the grooves between the spirals. (Dall and Bartsch, altered.) Odostomia (lolaea) eucosmia Dall and Bartsch Osdlla inscvlpta (Carpenter) Keep, West Coast Shells, p. 52, 1888, not Odoslmnia insculpta De Kay, 184.3. Odostomia [lolsea) eucosmia Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 183, pi. 20, figs. 10, 10a, 1909; Dall, Bull. 112, p. 130, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene of San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Pedro, California, to Point Abreojos, Lower California, Mexico (Jordan). Subgenus MENESTHO Moller, 1842 Menestho Moller, Index Moll. Groenl., p. 10, 1842; Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 184, 1909. Shell not umbilicated, marked by moderately well developed and usually equally spaced spiral cords; axial sculpture reduced to mere lines of growth, which frequently appear as very slender raised threads in the grooves between the cords. (Dall and Bartsch.) Odostomia (Menestho) grammatospira Dall and Bartsch in Arnold Odostomia (Osdlla) grammatospira Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 285, ])1. 1, figs. 6, 6a, 1903. Odostomia (Menestho) grammatospira Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 185, pi. 21, figs. 7, 7a, 1909. Pleistocene: San Diego. Recent: Lower California, Mexico. Odostomia (Menestho) aequisculpta Carpenter Odostomia (Evalea) squiscnlpta Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 14, p. 46, 1864. Odostomia (Osdlla) sequisculpta Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 284, pi. 1, figs. 3, 3a, 1903. Odostomia (Menestho) a'quisculpta Carpenter, Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 191, pi. 20, figs. 3, 3o, 1909. Pleistocene: San Diego. Recent: Cape San Lucas, Lower California, Mexico. Subgenus EVALEA A. Adams, 1860 Evalea A. Adams, Ann. Mag. Nat. Hist., Ser. 3, Vol. 6, p. 22, 1860. Odostomias with the surface marked by fine, incised spiral lines. (Dall and Bartsch.) Odostomia (Evalea) io Dall and Bartsch "Odostmnia tenuis Carpenter," Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 281, pi. 1, fig. 14, 1903, not of Carpenter, 1856. Odostomia (Evalea) io DaU and Bartsch, U. S. Nat. Mus., Bull. 68, p. 199, pi. 22, fig. 4, 1909; Dall, Bull. 112, p. 133, 1921; Waterfall, Univ. Calif. Publ. Geol., Vol. 18, p. 78, 1929. Pliocene: "Pico" formation near Ventura (Waterfall). Pldstocene: "Saugus" formation near Ventura (Waterfall); rare in lower and upper San Pedro formations in San Pedro region, Los Angeles County; also in the Pleistocene near Ventura and at San Diego (Arnold). Recent: Santa Rosa Island to San Pedro and Catalina Island, California. Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 875 Odostomia (Evalea) phanea Dall and Bartsch Plate 24, Figure 25 "Odostomia (Evalea) govldii Carpenter," Dall and Bartsch, in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 282, pi. 1, fig. 15, 1903. Odostomia (Evalea) phanea Dall and Bartsch, Proc. V. S. Nat. Mus., Vol. 33, p. 528, pi. 48, fig. 7, 1907; Bull. 68, U. S. Nat. Mus., p. 204, pi. 23, fig. 5, 1909; Dall, Bull. 112, p. 134, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 200, pi. 63, fig. 5, 1927. Pleistocene: San Diego, San Pedro, and Ventura (Dall and Bartsch in Arnold, 1903); upper Pleistocene terrace southwest of Goleta, Santa Barbara County (coll. by U. S. G.j. Recent: Monterey, California. This species has a prominent oblique fold on the upper part of the columella. In this character and in general shape it is like 0. (Amaura) gouldii Carpenter. A specimen from the late Pleistocene sands southwest of Goleta appears to belong to this species. Compare also plate 32, figure 20. Odostomia (Evalea) minutissima Dall and Bartsch Odostomia (Evalea) minutissima Dall and Bartsch, U. S. Nat. Mus., Bull. 68, p. 211, pi. 25, fig. 4, 1909; Dall, Bull. 112, p. 134, 1921; E. K. Jordan, Proc. Calif. Acad. Sci., Ser. 4, Vol. 15, p. 246, 1926. Pleistocene: Upper Pleistocene at San Quintin Bay, Lower California, Mexico (Jordan). Recent: San Diego, California, to Point Abreojos, Lower California, Mexico (Dall). Odostomia (Evalea) orfordensis Bartsch Odoslmnia (Evalea) orfordensis Bartsch, Proc. U. S. Nat. Mus., Vol. 52, p. 667, pi. 43, fig. 2, May 29, 1917. Pliocene: Elk River beds, mouth of Elk River, Port Orford, Oregon, upper Pliocene (Bartsch). Odostomia (Evalea) pleioregona Bartsch Odostomia (Evalea) pleioregona Bartsch, Proc. U. S. Nat. Mus., Vol. 52, p. 666, pi. 42, fig. 5, pi. 45, fig. 6, 1917. Pliocene: Elk River beds, mouth of Elk River, Port Orford, Oregon, upper Pliocene (Bartsch). Odostomia (Evalea) teresa T. S. Oldroyd Odostomia (Evalea) teresa T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 31, pi. 1, fig. 10, 1925. Pleistocene: Lower San Pedro series of Nob Hill cut, San Pedro, Los Angeles County (T. S. Oldroyd). Odostomia (Evalea) civitella T. S. Oldroyd Odostomia (Evalea) civitella T. S. Oldroyd, op. cit., p. 32, pi. 2, fig. 7, 1925. Pleistocene: Nob Hill cut, San Pedro. Odostomia (Evalea) fitella T. S. Oldroyd Odostomia (Evalea) fUella T. S. Oldroyd, op. cit., p. 33, pi. 1, fig. 8, 1925. Pleistocene: Nob Hill cut, San Pedro. Odostomia (Evalea) ithea T. S. Oldroyd Odostomia (Evalea) ithea T. S. Oldroyd, op. cit., p. 31, pi. 1, fig. 2, 1925. Pleistocene: Nob Hill cut, San Pedro. 876 San Diego Society of Natural History [Memoirs Odostomia (Evalea) manca T. S. Oldroyd Odostomia (Evalea) manca T. S. Oldroyd, op. cit., p. 32, pi. 1, fig. 5, 1925. Pleistocene: Nob Hill cut, San Pedro. t Odostomia (Evalea) steamsii Dall and Bartsch in Arnold Odostomia {Evalea) steamsii Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 282, pi. 1, fig. 12, 1903. Pleistocene: San Diego. Subgenus AMAURA MoUer, 1842 Amaura Moller, Index Moll. Groenlandica, p. 7, 1842. Very large, usually inflated Odostomias, the sculpture of which consists of very fine lines of growth and still finer, wavy, closely placed spiral striations. (Dall and Bartsch.) Odostomia (Amaura) satura Carpenter Odostomia satura Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 29, 1865. Odostomia satura var. pupiformis Carpenter, op. cit., p. 29, 1865. Odostomia {Amaura) pupiformis Carpenter, Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 283, pi. 1, fig. 13, 1903. Odostomia {Amaura) satura (Carpenter), Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 529, pi. 48, figs. 5, 5a, 1907; U. S. Nat. Mus., Bull. 68, p. 221, pi. 27, fig. 1, 1909; DaU, BuU. 112, p. 136, 1921. Pleistocene: San Diego, California (Dall and Bartsch in Arnold, 1903). Recent: Neah Bay, Washington (Dall and Bartsch). Odostomia (Amaura) gouldii Carpenter Odostomia (? var.) gmildii Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 29, 1865. Odostomia {Evalea) gouldi Carpenter, Dall and Bartsch, Proc. U. S. Nat. Mus., Vol. 33, p. 531, pi. 48, fig. 4, 1907; Bull. 68, U. S. Nat. Mus., p. 224, pi. 27, fig. 2, 1909; Dall, Bull. 112, p. 136, 1921; not of Dall and Bartsch in Arnold, Mem. Calif. Acad. Sci., Vol. 3, p. 282, pi. 1, fig. 15, 1903, = 0. {Evalea) phanea. Type specimen: In the U. S. National Museum, No. 22,821. Type locality: Neah Bay, Washington. Recent: Neah Bay, Washington (Carpenter). This species is similar to Odostomia (Evalea) phanea Dall and Bartsch, but is dis- tinguished by subgeneric characters. It does not appear to have been correctly reported as a fossil. Odostomia (Amaura) avellana Carpenter Cf. Plate 32, Figure 20 Odostomia (? var.) avellana Carpenter, Ann. Mag. Nat. Hist., Ser. 3, Vol. 15, p. 30, 1865. Odostomia (Amaura) nudformis avellana Carpenter, Dall and Bartsch in Arnold, Mem. CaUf. Acad. Sci., Vol. 3, p. 283, pi. 1, fig. 11, 1903; Proc. U. S. Nat. Mus., Vol. 33, p. 530, pi. 48, figs. 1, la, 1907; U. S. Nat. Mus., BuU. 68, p. 225, pi. 28, fig. 3, 1909; Dall, Bull. 112, p. 136, 1921; I. S. Oldroyd, Stanford Univ. Publ. Geol., Vol. 2, Pt. 2, p. 212, pi. 64, fig. 3, 1927. Pleistocene: Deadman Island, Los Angeles County, and Ventura; ? upper Pleistocene southwest of Goleta, Santa Barbara Co. Recent: Neah Bay, Washington. Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 877 Odostomia (Amaura) menzola T. S. Oldroyd Odostmnia (Amaura) menzola T. S. Oldroyd, Proc. U. S. Nat. Mus., Vol. 65, Art. 22, p. 33, pi. 2, fig. 6, 1925. Pleistocene: Nob Hill cut, San Pedro, Los Angeles County, as lower San Pedro series (Oldroyd). Odostomia (Amaura) sanesia T. S. Oldroyd Odostomia {Amaura) sanesia T. S. Oldroyd, op. cil., p. 34, pi. 1, fig. 13, 1925. Pleistocene: Nob Hill cut, San Pedro. Odostomia (Amaura) timessa T. S. Oldroyd Odostomia {Amaura) timessa T. S. Oldroyd, op. cil., p. 35, pi. 2, fig. 4, 1925. Pleistocene: Nob Hill cut, San Pedro. Odostomia (Amaura) trochilia T. S. Oldroyd Odostomia (Amaitra) trochilia T. S. Oldroyd, op. cit., p. 34, pi. 2, fig. 1, 1925. Pleistocene: Nob Hill cut, San Pedro. The type specimens of the forms named by T. S. Oldroyd in 1925 are in the U. S. National Museum. 878 San Diego Society of Natural History [Memoirs CLASS AMPHINEURA The Amphineura are a group of bilaterally symmetrical mollusks commonly grouped with the gastropods as a subclass but in many ways quite distinct. They are subdivided into the order Polyplacophora, including the chitons, and the order Aplacophora. The latter lack the plates and are practically without the foot of the former. They have not been found fossil in California. The Polyplacophora, or chitons, are elongate animals, adhering to rocks or other objects by a foot that is coextensive with the body. Dorsally they are provided with eight transverse chitonous plates or valves. These valves are occasionally found as fossils; but except for a few unusual localities, they are relatively rare. Limitations of time and space made it necessary to omit a treatment of the group in this memoir. The following are some of the more important references to the occurrence of chitons as fossils on the Pacific coast of North America: Arnold, R., Mem. Calif. Acad. Sci., Vol. .3, pp. 342-343, 1903. Berry, S. S. : "Preliminary Notices of Some New West American Chitons," Lorquinia (Los Angeles), Vol. 2, No. 6, pp. 4-7, January, 1919. : "Fossil Chitons of Western North America," Proc. Calif. Acad. Sci., Ser. 4, Vol. 11, pp. 399-526, ppl. 1-16, also text figs.. May 16, 1922. "Fossil Chitons from the Pleistocene of San Quiiitin Bay, Lower California," Amer. Joum. Sci., Ser. 5, pp. 455-456, November, 1926. A checklist of the Recent occurrences from California northward is given by Dall, and data on Recent species is also given by Oldroyd: Dall, W. H., Bull. 112, U. S. Nat. Mus., pp. 186-199, 1921. Oldroyd, I. S., Stanford Univ. Publ. GeoL, Vol. 2, Pt. 3, pp. 246-323, 1927. In 1927, the Royal Society of New South Wales published a monograph of the Australian Loricates by Iredale and Hull containing much generic discussion of impor- tance to those interested in the systematics of this group. In concluding it might be well to mention that the species in some of the groups of chitons have been overnamed. PLATES 1-32 i 880 San Diego Society of Natural History l Memoirs EXPLANATION OF PLATE 1 Fic. 1. Yolilia scissuraia Dall, Recent specimen from Pviget Sound, labeled A in the collection at Stan- ford LTniversity. Right valve, length 36 mm I'age 131 Figs. 2. Niiculana minula (Miller, 1776), reproduction of figures of a Recent specimen from Greenland by Hanley in Sowerby, Thes. Conch., Vol. 3, \). 114, NucuUds-, pi. 3, figs. 61, 62, 1860. Fig. 2a, umbonal view; fig. 26, right valve; length 14 mm page 122 Figs. 3. Nitcula (Acila) mirdbilis Adams and Reeve, Recent specimen from Japan, labeled 308A in the collection at Stanford University. Fig. 3a, left valve; fig. 3b, posterior view; length 23 mm. This species is practically indi tinguishable from the well-known Nucula (Acila) geUysburgensis Reagan of the Oligooene of Washington page 113 Fig. 4. Nucula {Nucula) nucleus (Linnseus), Recent specimen from England or France, labeled 1362A in the collection at Stanford LTniversity. Exterior of left valve, length 7 mm ])age 110 Fig. 5. Nucula (Niicida) 7iucleus (Linnseus), another specimen from the same lot as that shoAvn in fig. 4. Interior of left valve, length '.) mm. This species is the type of the gemis Nuculn Lamarck page 110 Figs. 6. Nucula {Acila) caslrensis Hinds, Recent specimen from Puget Soimd. lalieletl A in the collec- tion at Stanford University. Fig. 6a, exterior of left valve; fig. 6/j, interior of left valve; length 17 mm page 116 Fig. 7. Yoldia limatula (Say), Recent sjjecimen from Puget Soimd, labeled A in the collection at Stanford LTniversity. Exterior of left valve, length 28 mm page 131 Fig. 8. Nuculaua tai)hria (Dall), specimen No. 77 S. D. S. N. H., from locality 2176, middle Pliocene of Holser Canyon, Los Angeles Co. Exterior of right valve, partial length 17 mm. Unfortunately the shapes of figs. 8 and 9, as well as those of some of the Nuculas, have been injured somewhat during the preparation of the plates page 121 Fig. 9. Nuculatia taphria (Dall), specimen No. 78 S. D. S. N. H., from locality 98, Pleistocene near Goleta, Santa Barbara Co. Exterior of right valve, length 16 mm page 121 Fig. 10. Yoldia arctica (Gray), typical variety, reproduction of a figure of a Recent specimen from the Lapteff Sea (75° 42' N., 124° 41' E.) by Mossevitch, Acad. Sci. Union Rep. Sov. Soc, Livraison 19, pi. 1, fig. 3, 1928. Exterior of right valve, proliably enlarged x 2. This species is the type of the genus Yoldia MoUer . pages 126, 127 Fig. 11. Yoldia arctica (Gray), typical variety, reproduction of Mossevitch's fig. 1, of a siiecimen from deep water in the White Sea to show the variation that Mossevitch recognizes even in the typical variety. Mossevitch records many specimens and several other varieties. Exterior of right valve, probably enlarged x 2 pages 126, 127 Figs. 12. Yoldia Ihraciseformis (Storer), Recent specimen from Puget Sound, labeled A in the collection at Stanford University. Fig. 12a, interior of right valve; fig. 126, exterior of left valve; length 44 mm page 128 Fig. 13. Yoldia cooperi Gabb, Recent specimen from Halfmoon Bay, middle California, labeled 19-2A in the collection at Stanford University. Exterior of the left valve, length 64 mm. (See also plate 14, fig. 3, for view of the interior.) This species is the type of the new section Kolayoldia page 128 Fig. 14. Nuculanu hamata (Carpenter), Recent specimen from San Pedro, in box lalicled 14A in the collection at Stanford University. Exterior of left valve, x 5, length 9 mm iiagc 125 Fig. 15. Nuculana hamata (Carpenter), another sijccimen from the same lot as the last. Exterior of right valve, x 5, length 6 mm page 125 Fig. 16. Cuspiitaria (Cardioinya) pt'clinala (Carpenter), Recent specimen from San Pedro, in box lal)eled 33A in the collection at Stanford University. Exterior of right valve, x 5, length 7.8 mm. This species is shown here although it belongs with the Thraciida- to illustrate the similarity of its shape with that of Nuculana hamata. Although it lacks the small taxodont teeth of the latter, which it may once have had and lost, several features suggest that it should not be placed in a different order page 265 {Continued on page SSS) Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA PlATE 1 ^^.. 6a VoLUMK I ] Pliocene and Pleistocene Mollusca of California 883 EXPLANATION OF PLATE 1— (Continuc7 nnn. This form occurs in a nimiber of places in the Pliocene of California, but it is probably not of particular significance page 139 Fig. 2. Peelen [Janira) hellus (Conrad), variety close to eoalinga'crma Arnold in F. iSL Anderson, speci- men No. 86 S. D. S. N. H., from locality 228, middle Pliocene southeast of Pico Canyon, Los Angeles Co. Right valve, length and altitude 31 mm., convexity S mm I'age 227 FiCi. 3. Vecten. (Janira) hellus (Conrad) variety slerini Dall and Ochsner, s))ecimen No. 87 .S. D. S. N. H., from locality 258, middle Pliocene (oyster-bed facics) north of the Santa Clara Valley and east of San Martinez Chiciuito Canyon, Los Angeles Co. Right valve, length 65 mm., altitude 47 mm., convexity 17 mm. The unusual lengtli of this form is not due to the crack in the middle, for other specimens without the crack have the .same outline page 227 Fic. 4. Area (Area) Irilineata Conrad, specimen No. 435 in the collection at Stanford University, from the basal Pliocene of Elsmere Canyon, Los Angeles Co. Left valve, length 47 mm. . . . page 139 Fic:s. 5. Area (Area) inidlieoslata Sowerby variety eamidoennis Osmont, specimen No. 85 S. D. S. N. H.. from locality 228, middle Pliocene southeast of Pico Canyon, Los .\ngeles Co. Right valve of an unusually large, gerontic individual: fig. 5a, view of back; fig. .56, view of cardinal area; fig. 5c, view of anterior end; all x %, altitude 102 mm., length 95 mm., convexity 54 mm. Such a form as this might easily be mistaken for a new species .... page 139 FiC'S. 6. Area (.4iro) trilinea.ta Conrad variety ealearea, new variety, type, specimen No. 436 in the collection at Stanford University, from the San Diego well, middle Pliocene. Left valve: fig. 6a, interior showing the many cardinal grooves and the ponderosity of the shell; fig. 66, exterior view; length 80 mm. This variety appears to be characteristic of the middle Pliocene of the Santa Clara Valley region as well as of San Diego. It is analogous to the variety eamuloensis of Area muliieostata page 140 Volume I] PlIOCEXE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA PlATE 2 -ssy^ '"^ ~- 886 San Diego Society of Natural History [ Memoirs EXPLANATION OF PLATE 3 Figs. 1. Pectin. (Jiniira) helliits (Conrad) variety henipliilli Dall, speoimeii No. 88 S. D. S. N. H., from locality 100, middle Pliocene at Pacific Beacli, San Diego. I''ig. lo, exterior of right valve; fig. 1/), exterior of left valve; length 75 mm., convexity of right valve 17 mm., left valve flat. This variety is ])ractically indistinguLshable from the typical variety page 226 Figs. 2. Pccloi (Jaiiira) .ileaninii Dall, typical variety, specimen No. 90 S. D. S. N. H.. from locality 217o, middle Pliocene of Holser Canyon, Los Angeles Co. Right valve: fig. 2a, iimbonal view showing the high, narrow ribs; fig. 2b, view looking straight down at it; length 71 mm., convexity lo nnn I'^ige 223 Figs. 3. Peclcn (Jcinira) vogdesi Arnold, Recent specimen from the CJulf of California, labeled 1588A in the collection at Stanford University. Fig. 3a, exterior of right valve; fig. 3fe, exterior of left valve; length (12 mm., convexity of right valve 22 mm., concavity of left valve 5 mm page 228 Fig. 4. Pcclen (Janira) stearnsii Dall variety diegcnsis Dall, specimen No. 89 S. D. S. N. H., from locality 226, middle or lower Pliocene near the month of Smith Canyon (first canyon east of Torrey Canyon) south of the Santa Clara Valley, Ventura Co. Right valve, length 80 mm., convexity 11 mm. This form is somewhat intermediate between bellus and stearrisii, but the depressed form and number of ribs clearly relate it to the variety diegensis of the latter page 223 Volume I ] PlIOCENE A\D PLEISTOCENE ]\IOLLrSCA OF CALIFORNIA PlATE 3 5b ''"-^^ A 888 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 4 Figs. 1. Peclcn (Janira) stcarnsii Dall variety hakcri Haiiiui and Hcrtlein, jilesiotype, No. 91 S. D, 8. N. H., from locality 32, Santa Ro-salia, Lower California, probably Pliocene. Fig. In, right valve; fig. 16, left valve; altitude 112 mm page 224 Figs. 2. Peclcn (Aeguipectcn) pvrpiiratus Lamarck, Recent s]:>ecimen from Coquimbo, Chile, No. 437 in the collection at Stanford University. Fig. 2a, right valve; fig. 2b, le't valve; fig. 2c, umbnnal view showing tlie relative convexity of the two valves (right valve below, in the natiu'al iiosition) ; length 77 mm page 207 Fig. 3. Peclen {Aeqwipectcn.) latiauraius Conrad variety monoiimcris Conrad, specimen No. 92 S. D. S. N. H., from locality 78, 3-^ mi. S. of Seacliff Sta. on the Southern Pacific R. R., Ventura Co., Pleistocene terrace. Exterior of right valve, length 28 mm page 204 Fig. 4. Pccten (Acquipecten) andcrsoni Arnold, specimen No. 93 S. D. S. N. H., from the middle Mio- cene of Barker's Ranch, Kern Co. Exterior of the right valve, length 24 mm. This species is difficult to distinguish from the tyjiical variety of hiliuiirahis on the one hand and from discus on the other page 202 Fig. 5. Pccten (Aequipeclen) andersoni Arnold, specimen No. 94 S. D. S. N. H., from the same locality as the last. Exterior of the right valve, length 40 mm page 202 Fig. 6. Peclcn (Acquipecten) laiiauratus Conrad variety monniiincris Conratl, Recent specimen from San Diego, No. 95 S. D. S. N. H. E.vt.erior of right valve, length 34 mm page 204 Fig. 7. Pccten (Acquipecten) discus Conrad, sjiccinien No. 96 S. D. S. N. H., from the Santa Margarita formation, upper Miocene, from a dei)th of 46.5.') feet in the Superior Oil Company's well, Ansolabehere No. 1, northwest of Bakersfield, Kern Co. Exterior of right valve, altitude 47 mm. This species is doulitfidly distinguisliable from Peclcn opercularis (Linnaeus), the type of Acquipecten page 200 Volume I 1 PlIOCENE AND PLEISTOCENE ^lOLLUSCA OF CALIFORNIA PlATE 4 ,,,l I la i - J lb X-3 "^k ^'^Mmm^f' 890 San Diego Society of Natural History [ Memoirs EXI'LAXATIOX OF PLATE 5 Fio. 1. Pecten (Aequipecleii) purpuralus Lamarck variety aubdolus Hcrtlein, specimen X^o. 97 S. D. S. X. H., from the middle Pliocene of locality 214, west of Fernando Pass, Los Angeles Co. Exterior of right valve, length 52 mm. The unusual width of the rib.s on this specimen may be partly due to erosion page 211 Fig. 2. Pecten (Acquipeclen) purpiirnlus Lamarck variety crislobalensis Hertlein, type, specimen Xo. 36 in the collection at Stanford University, from 3 mi. south of Turtle Bay, Lower California, Pliocene. Exterior of right valve, length 135 mm. This specimen is intermediate between the most characteristic forms of crislobalensis and the variety liiikci. A small specimen would be like callidus page 210 Fig. 3. Pecten (Aequipecten) deserti Conrad, type variety, specimen Xo. 98 S. D. S. X. H., from the (middle ?) Pliocene of the Carrizo Creek beds. Imperial Co. Exterior of right valve, length 35 mm page 212 Fig. 4. Pecten (Aequipecten) purpuratus Lamarck variety callidus Hertlein, specimen Xo. 99 S. D. S. X. H., from the middle Pliocene of locality 212, west of Fernando Pass, Los .\ngeles Co. Exterior of right valve, 52 mm page 211 Figs. 5. Pecten (Aequipecten) deserti Conrad variety inralidus Hanna, specimen Xo. 100 S. D. S. X. H., from the middle Pliocene of locality 217/), Holser Canyon, Los Angeles Co. Fig. 5a, exte- rior of right valve; fig. 56, umbonal view showing the equal convexity of the valves (right valve below); fig. 5f, exterior of left valve; length 39 mm., altitude 40 mm., convexity of the two valves 18 mm page 213 Figs. 6. Pecten (Aequipecten) deserti Conrad variety inralidns Hanna, variation leaning toward Pecten gibbns, perhaps should be called Pecten t/ibhus variety, s]ieciinen Xo. 101 8. D. S. X. H., from the same locality as the last. Fig. 6a, exterior of right valve; fig. 66, side view (right valve below); fig. 6c, exterior of left valve; length 39 mm., altitude 37 mm., convexity of the two valves 20 mm. This form is more convex and more circular in outline than the normal specimens of deserti. It has the form of ericellus Hertlein page 213 Figs. 7. Pecten (Aeqtnpecten) gibbus (Linnajus) variety circularis Sowerby, Recent specimen from San Diego, labeled 1587A in the collection at Stanford LTniversity. Fig. 7a, exterior of right valve; fig. 76, umbonal view showing the greater convexity of the right valve; fig. 7c, exterior of left valve showing, among other things, the one white rib characteristic of Pecten gibbus; length 46 mm., altitude 44 mm., convexity of the two valves, 27 mm. . . . page 218 Volume I ] PLIOCENE AND PLEISTOCENE ^loLLUSCA OF CALIFORNIA PlATE 5 892 San Diego Society of Natural History [ Memoirs EXPLANATION OF PLATE 6 Figs. 1. Pecten (Piiliiiopccle7i) healeyi Arnold variety lohri Hertlein, specimen No. 102 S. D. 8. N. H., from the basal Pliocene of locality 209, Elsmere Canyon, Los ^\ngeles Co. Fig. lo, exterior of right valve; fig. 16, exterior of left valve; both fignres x %] length 9S mm. This is the ancestral varietj' of the sijecies page 197 Figs. 2. Pecten {Palinopcrtcn) healeyi Arnold, typical variety, specimen No. 103 S. D. S. N. H., from the middle Pliocene of locality 100, Pacific Beach, San Diego. Fig. 2a, exterior of right valve with left valve showing liehind; fig. 2ti, exterior of left valve; a small s]K'cimen, length 85 mm page 196 Fig. 3. Pecten (Patinopecten) purisimaensis Arnold, specimen No. 104 S. D. S. N. H., from the Purisima formation, lower Pliocene, of locality 103 near the mouth of San Gregorio Creek, San Mateo Co., middle California. Exterior of right valve, x %, altitude 128 mm page 194 Fig. 4. Pecten (Patinopecten) caurinus Gould, specimen No. 105 S. D. S. N. H., from the upper Pliocene of locality 225 between Timber Canyon and Santa Paula Creek, Ventura Co. Exterior of right valve, somewhat distorted, x %, length about 140 mm., altitude 123 mm., convexity 20 mm., the left valve nearly flat. This species is very common in this and nearby local- ities of the same horizon, but it is difficult to get a complete specimen page 194 Volume I ' Pliocene and Pleistocene Mollusca of California Plate 6 894 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 7 Figs. 1. Pecleii (Vertipeclen) nevadanus Conrad variety /hcoohs Dall, specimen No. 4.38 in the collection at Stanford L^niversity, labeled Miocene of Kern River. Fig. la, exterior of right valve, which is practicalh" flat; fig. lb, exterior of left valve; altitude 98 mm page 190 FiG.s. 2. Pecten (Vertipeclen) neradanus Conrad, typical variety, neotjije, specimen No. 431 in the collection at Stanford ITniversity, said to have come either from the McKittrick Di.strict or from the Santa Monica Mts., southern California, middle Miocene. Fig. 2a, exterior of right valve, which is not quite so flat as the right valve shown in fig. la; fig. 2b, exterior of left valve; fig. 2f, posterior profile; the three views approximately % natural size, length 200 mm. This specimen is selected as the neotype because of its unusually fine state of preservation, even if the locality is somewhat in doubt. Fragmentary specimens from Conrad's locality show the same characters page 189 Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA PlATE 7 ^.U^\ 896 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 8 Figs. 1. Peclcn (Lijropecten) esirellanus (Conrad) variety cerrosensis Gabb, specimen No. 107 S. D. S. N. H., from the middle Pliocene of locality 228, southeast of Pico Canyon, Los Angeles Co. A large, humped-up, gerontic individual; fig. la, interior of the hinge showing the diverging grooves; fig. 16, exterior of the same valve, the left valve; both views x H, length 176 mm page 187 Figs. 2. Pcden {Lyropecten) esirellanus (Conrad) variety cerrosensis Gabb, specimen No. 108 S. D. S. N. H., from the middle Pliocene of locality 2176, Holser Canyon, Los Angeles Co. A small specimen showing faintly a differentiation of the ribs as in P. nochsus: fig. 2a, exterior of right valve; fig. 26, exterior of left valve; both views x H, length 79 mm page 187 Fig. 3. Pcclen {Aequipecien) purpuratus Lamarck variety hakei Hertlein, type, specimen No. 40 in the collection at Stanford University, from the Pliocene of Turtle Bay, Lower California. Exterior of right valve, x %, length 135 mm. This variety is probably the same as P. purpuratus variety crislobalensis shown on plate .5, figure 2, but it is included here because it is likely to be mistaken for a Lyrope.cten. It is large and has an abnormally heavy, incrassated shell; but its lack of diverging grooves on the interior of the hinge, its longer hinge line, and its intergrading with the other varieties or variations of P. pur- piiraliis with which it lives show it to be an Aequipecien page 209 Fig. 4. Peclen (Lyropeclen) esirellanus Conrad, typical variety, specimen No. 106 S. D. S. N. H., from the basal Pliocene of locality 209, Elsmere Canyon, Los Angeles Co. Exterior of right valve, length approximately 11.5 mm., convexity of the right valve 20 mm. It is possible that this specimen should be referred to the variety calalinie Arnold (specimens of which were found with it), but it is larger, coarser, and somewhat more convex page 185 Volume I 1 PlIOCENE AND PLEISTOCENE IMOLLUSCA OF CALIFORNIA PlATE 8 898 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 9 Fig. 1. Peclen (Lyrope.clen) magnijicus Sowerby, typical variety, Recent specimen from the Galapagos Islands, No. 439 in the collection at Stanford LTniversity. Exterior of small left valve, length 78 mm. See also plate 10, figure 6 page 182 Fig. 2. Peclen (Lyropecten) estrellanus (Conrad) variety cerrosensis Gabb, specimen No. 109 S. D. S. N. H., from the middle Pliocene of locality 263 between Fernando Pa.ss and Pico Canyon, Los Angeles Co. Exterior of right valve, x ?3, length 127 mm page 187 Fic:. 3. Peclen {Lyropecten) jeffersonius Say, specimen No. 441 in the collection at Stanford University, from the Miocene of the Atlantic Coast. Exterior of right valve, x %, length 147 mm. . page 176 Fig. 4. Peclen. (Lyropecleii) in/ n ' jy ^^. '^s^^** M\^y. ^^mi^i>r / /< fMI .>'•*' h> ;n'\V^ 2 X?3 900 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 10 FiGP. 1. Peclcn (PalUiini) siriflii Bernardi, reproduction of the original figvn'es of the type sjjeciraen, Recent in Japan, from the Journal do Conchyliologie, Vol. 7, p. 90, pi. I, fig. 1, pi. 2, fig. I, 1858. Fig. Id, exterior of the right valve; fig. 16, exterior of the left valve; both illustra- tions reduced } 2, altitude 105 mm., length S9 mm page 171 Fig. 2. Pictcii. (Palliuw) suiflii Bernardi, form juirmdcci Da!l, specimen No. 110 S. D. S. N. H., from the middle Pliocene of locality 2\l(i, Holser Canyon, Los Angeles Co. Exterior of right valve, altitude 50 mm., length 53 mm. This form is so close to the typical that it is liardly worth while to try to separate it page 171 Figs. 3. Pccten {PaUiuin) swiflii Bernardi, form imtld Arnold, specimen No. Ill S. D. S. N. H., from the middle Pliocene of locality 2I7o, Holser Canyon, Los Angeles Co. Fig. 3a, exterior of right valve; fig. 3b, exterior of left valve; altitude 37 mm., length 32 nmi. This form is merely a variation of the variety cichegoini page 173 Figs. 4. Peclen {PaUium) suriflii Bernardi, Recent specimen from Notoro Bay, Hokkaido, Jajxin, No. 112 S. D. S. N. H. Fig. 4n, exterior of right valve; fig. -tb, exterior of left valve; both figures X 3i, altitude 102 mm., length 88 mm. This species is a typical member of the section Manupec'en page 171 Fig. 5. Pccten (PaUium) swiflii Bernardi, form parrneleci Dall, specimen No. 113 S. D. S. N. H., from the middle Pliocene of locality 217, Holser Canyon, Los Angeles Co. Exterior of right valve, altitude 43 mm., length 40 nun. Comjiare fig. 2 page 171 Fig. 6. Pccten (Lyropccten) magnificus Sowerby, typical variety. Recent specimen from the Cialapagos Islands, No. 439 in the collection at Stanford University. Exterior of the riglit valve of a large specimen, reduced H, length 174 mm. It will be noted that this specimen is more like the usual form of the variety crassicardo than are any of the specimens shown on plate 9 page 182 Fig. 7. Peclcn (Pallium) swiftii Bernardi, form kindlei Dall, specimen No. 444 in the collection at Stanford University, from the Pliocene (or Pleistocene) of Nome, Alaska. Exterior of right valve, x %, altitude 90 mm., length about 75 mm page 174 Volume I ] PlIOCENE AND PLEISTOCENE MoLLUSL'A OF CALIFORNIA PlATE 10 p '•** #-5 ' , - 902 San Diego Society of Natural History imemoiks EXPLANATION OF PLATE II Figs. 1. Pccten iPecien) islandicus MuUer, Recent specimen from Eastport, Maine, labeled 1600A in the collection at Stanford University. Fig. la, exterior of right valve ; fig. 16, exterior of left valve; altitude 81 mm., length 74 mm. This form is identical with that found in the north Pacific page 161 Fic. 2. Pcctm (Pccten) hcringianns Middendorff, specimen No. 11-1 S. D. S. N. H., from locality 218, upjjer Pliocene of Sulphur Canyon east of South Mt., Ventura Co. E.xterior of left valve, altitude 23 mm., length 19 mm. This is a small specimen of a form that was originally described as a variety of islnyidiciis and may even be a variety of islnndicus. It illustrates how easy the transition may have been from forms like Propcamustiiiuii or Pseudamtissium to Chlamys page 165 Fig. 3. Peclcn (Pccten) opiintia Dall, specimen No. 44.5 in the collection at Stanford University, from the Calabasas Quadrangle, Ventura or Los .\ngeles Co., probably middle Pliocene. Ex- terior of left valve, altitude 69 mm., length 67 mm. The sculpture on the other valve is practically the same. This form probably intergrades with the varieties of islandicus, but it seems to be better characterized page 16.5 Fig. 4. Pccten (Pecten) islandicus Miiller \a,riety jordani Arnold, sjiecimen No. 11.5 S. D. S. N. H., from the upper Pliocene of locality 39, Packard's Hill, Santa Barbara. Ex-terior of right valve, altitude 44 mm., length 42 mm. There is very little to distinguish this variety from a small specimen of the typical variety, and less to distinguish it from hindsii page 164 Figs. 5. Pecten (Pecten) multirugosus Gale, young Recent specimen from San Pedro, labeled 103-lA in the collection at Stanford ITniversity. Fig. .5a, exterior of right valve; fig. 5b, ex-terior of left valve; altitude 27 mm. This specimen has just begun its sessile stage, which shows that it belongs to the typical section of Pecten, formerly called Hinnites; but it is almost obvious that it should be classified in the same subgenus as Cldamys and close to P. hasiatus page 159 Figs. 6. Pccten (Pecten) hasiatus Sowerby, specimen No. 447 in the collection at Stanford University, from the Simi Rancho, Ventura Co., probably lower Pleistocene. Fig. 6a, exterior of right valve; fig. Gb, exterior of left valve; altitude 55 mm,, length 49 mm page 166 Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA PlATE 11 ■M^. 904 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 12 Figs. 1. Oslrca ivspej-tiiin Conrad, normal variety, spocimon No. 116 S. D. S. N. IL, from locality '2\7a, niiddlp Pliocene of Holser Canyon, Los Angeles Co. Fig. la, interior view showing hinge and muscle scar; fig. 16, exterior of the same valve; altitude (greatest dimension) 7t) mm. . page 152 Fig. 2. Anomia perui'iana d'Orbigny, specimen No. 118 S. D. S. N. H., from locality 99, upper Pleisto- cene terrace west of Newport, Los Angeles Co. Exterior of upper valve (the left valve), greatest dimension 40 mm page 240 Fig. 3. Pododesmus man'oschisma (Deshayes), specimen No. 120 S. D. S. N. H., from locality 217, middle Pliocene of Holser Canyon, Los Angeles Co. Exterior of upper valve showing sculpture, greatest dimension 4.3 mm page 241 Figs. 4. Pododesmus macroschisma (Deshaj'es), specimen No. 446 in the collection at Stanford Univer- sity, from the upper San Pedro, ujijier Pleistocene, of Deadman Island, San Pedro Harbor, Los Angeles Co. Upper valve: fig. 4a, exterior showing sculjrture; fig. 46, interior showing the liro muscle scars (one adductor and one by.ssal); both views x Mi lengtli 100 nun . . . ))agc 241 Fig. .5. Anomia perui'iana d'Orbigny, Recent sjiecimen from the Gulf of California, in the collection at Stanford University, labeled 394-lA. Interior of the upper valve showing the three muscle scars (one adductor and two byssal), length 3.5 mm page 240 Fig. 6. Mytilus (Mylilus) californianus Conrad, Recent specimen from Seven Mile Beach, San Mateo Co., middle California, No. 117 S. D. S. N. H. Exterior, length 127 mm page 245 Fig. 7. Volsella recta (Conrad), form flabeUata (Gould), specimen No. 448 in the collection at Stanford University, from the Merced Pliocene at Capitola, .Santa Cruz Co., middle California Exterior of right valve, length 128 mm page 250 Fig. 8. Modiolaria Ismgata (Gray), Recent specimen taken off San Juan Island, Puget Sound, No. 119 S. D. S. N. H. Exterior of left valve, length 26 mm. This species is distinguished from nigra (Gray) by the lack of radial striations on most of its surface. It is, like discors (Linnaeus), divided into three radial compartments; but only the small anterior one is radially ribbed, whereas in discors the posterior one is also. The species Isevigata was described at the same time as nigra, on the same page. Its tjTDe locality is Greenland . . . page 254 Volume I 1 PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA PlATE 12 906 San Diego Society of Natural History [Memoirs explaxatiox of plate 13 Figs. 1. Ptnpluiiin /iluiiinsnila .Sowerby, Recent s|X'ciiiicri from Ft. Conception, Calif., No. 130 S. D. S. N. H. F"ig. la, exterior of right valve; fig. lb, interior of the same valve showing the hinge ajjparatus and the pallial sinus; length 49 mm page 255 Figs. 2. Pandora piinclala Conrad, specimen No. 121 S. D. S. N. H., donated from the collection at Stanford ITniversity where it was labeled 149, upper San Pedro (Palos Verdes), upper Pleistocene of San Pedro. Fig. 2a., exterior of the right valve; fig. 26, interior of the same valve ; length 31 mm page 262 Figs. 3. Aslarte alaskensis Dall, Recent specimen from Puget Sound, labeled A in the collection at Stanford University. Fig. 3a, interior of left valve; fig. Sb, exterior of the same valve; length 25 nun page 26S Fig. 4. Verlicordia ornala (d'Orbigny), Recent specimen labeled 40-lA in the collection at Stanford University, dredged at Santa Barbara. Exterior of left valve, x 5, length 5.5 mm. This little species is interesting because it is known also from China ami the .Antilles page 266 Figs. 5. Pandora grandis Dall, Recent specimen from Puget Sound, labeled 1()31.\ in the collection at Stanford University. Fig. 5a, interior of right valve; fig. 5b, exterior of left valve; length ■12 mm page 261 Figs. 6. Thracia {Cyalhodonia) undidata (Conrad), Recent specimen from San Diego, labeled 45-1 A in the collection at Stanford ITniversity. Fig. 6a, exterior of right valve, natural size, length 32 mm. ; fig. 66, hinge of right valve, x 2 page 259 Figs. 7. CrassHelliles anliUariun (Reeve), specimen No. 122 S. D. S. N. H., from locality 32, near Santa Rosalia, Lower California, probably Pliocene. Fig. 7a, interior of right valve; fig. 76, ex- terior of the same valve; length, 79 mm page 271 Fig. 8. Thracia {Thracia) trapezoides Conrad, specimen No. 123 S. D. S. N. H., from locality 41, middle Miocene south of Mayfield, Santa Clara Co., middle California. Exterior of left valve, lengtli 42 mm page 257 Figs. 9. Cardila venlricosa Gould, specimen No. 125 S. D. S. N. H., from the lower Pleistocene of Stan- ford University locality 533, on old road (elevation about 1150') about IJa mi- S. 15° E. of Shepliard's, on ridge between Casitas Creek and the Ocean, Ventura Quadrangle, Ventura Co. Fig. 9a, interior of right valve; fig. 96, exterior of the same valve; both views X 2, length 17 mm page 272 Figs. 10. Glans miuuacula, new species, type, specimen No. 126 S. D. S. N. H., from locality 78, upper Pleistocene terrace near Seacliff, Ventura Co. Fig. 10a, exterior of right valve; fig. 106, interior of same valve; both views x 3, length 11 mm. This species was formerly called ( 'arditn ttnhqnadrala page 277 Fig. 11. Cardila renlriroxa Gould, specimen No. 124 S. D. S. N. H., from locality 218, upper Pliocene of Sulphur Canyon east of South Mt., Ventura Co. Exterior of left valve, x 2, length 13 mm page 272 Fig. 12. Donax gonldii Dall, specimen No. 127 S. D. S. N. H., from locality 99, ujjper Pleistocene ter- race west of Newport, Los Angeles Co. Interior of the right valve, x 2, length 16.5 mm. The exterior of this specimen where the surface is intact is nearly smooth (hence its old name Ixvigatus, preoccupied); but where the surface has been weathered and removed there are pairs of fine radial knife-edges as in the Glycymeris shown on plate 1, fig. 216 . . , page 380 Figs. 13. Calyptogena paciftca Dall, Recent specimen from .Alaska, labeled IIO.A in the collection at Stanford University. Fig. 13a, interior of the left valve; fig. 136, exterior of the same valve; length 41 mm page 278 Figs. 14. Peiricoki carditoides (Conrad), specimen No. 128 S. D. S. N. H., from locality 41), upper Pleisto- cene terrace southwest of Goleta, Santa Barbara Co. Fig. 14a, interior of the right valve; fig. 146, exterior of the same valve ; length 38 mm. This species is very variable in outline, taking the shajie of the hole or crevice in which it lives page 355 Fig. 15. ThynHra bisecia (Conrad) variety nipponica Yabe and Nomura, specimen No. 129 S. D. S. N. H., from the Kawabata series, upper Pliocene or Pleistocene of Japan. Exterior of right valve, length 63 mm. This form is hardly to be distinguished from the North American form bisecta (Conrad) -f- di.ynncia (CJabb) page 281 Volume I 1 PlIOCEXE AND PLEISTOCENE ]\IOLLUSCA OF CALIFORNIA PlATE 13 908 San Diego Society of Natural History [Memoirs EXPLAXATIOX OF PLATE 14 Fias. 1. Dirarinlld ilrnlnia (Wood), variety ihiiniea (Reeve), Rerent specimen from Puerto Angeles, Oaxaea, Mexico, labeled A in the collection at Stanford I'niversity. Fig. lo, exterior of the right valve; fig. lb, interior of the same valve, length 2-t mm. This species is closely related to diraricnla (Linnaeus). The writers do not consider the differences between the Atlantic and Pacific forms of denlatn of more than varietal significance JJage 296 Fig. 2. Lucina (Here) excavata Carpenter, specimen No. 131 S. D. S. N. H., from locality 217b, middle Pliocene of Holser Canyon, Los Angeles Co. Interior of left valve, length 12.5 mm. This species is better known as richthofeni Gabb page 290 Fig. 3. Yoltliu cooperi Gabb, Recent specimen from Halfmoon Bay. View of the interior of the left valve. The exterior of this same specimen is shown on jikite 1, fig. 13 page 128 Figs. 4. Lucina (Myrtea) nutta]Ui Conrad, Recent specimen in the collection at Stanford University labeled 2270A, found on sandy mud flats between tides, San Diego. Fig. 4a, interior of the left valve; fig. 46, interior of the right valve; length 2(.i mm page 288 Fig. 5. Lucina (Here) exeavala Carpenter, specimen No. 132 S. D. S. N. H., from locality 217b, middle Pliocene of Holser Canyon, Los Angeles Co. Exterior of left valve, length 20 mm page 290 Figs. 6. Macon)a haUhica (Linnaeus), young specimen. No. 134 S, D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. Fig. 6a, interior of right valve; fig. 6b, interior of left valve; length 13.5 mm. The exteriors of this specimen are shown (in jilate 20, figs. 7a, 7b page 371 Fig. 7. Macnma moesln (Deshayes) variety acolasia Dall, specimen No. 135 S. D. S. N. H., from locality 74, upper Pleistocene terrace near Goleta, Santa Barbara Co. Interior of right valve, length 20 mm. The exterior of this specimen is shown on plate 20, fig. 10 page 371 Figs. S. Lvcina (Myrtea) tenuiscnlpla Carpenter form apj)roxunalo (Dall), specimen No. 136 S. D. S. N. H., from the Nob Hill cut, lower San Pedro Pleistocene of San Pedro, Los Angeles Co. Fig. 8a, interior of right valve; fig. 8b, exterior of the same valve; length 8.6 mm. The living southern form approximata is distinguished only by the stronger radial striations, and it is probable that the typical form living near Vancouver Island differs only in the state of preservation page 2S9 Figs. 9. TelUna nierejpsis Dall, Recent specimen from San Diego, labeled 277A in the collection at Stanford University. Fig. 9a, interior of right valve; fig. 9b, interior of left valve; length 15 mm. These interior views show faintly the lateral teeth distant from the beak that distinguish this form from a Macoma. The exterior views are given on plate 20, figs. 9a, 9b. T. reeliisa Dall may be the same species, and T. uilsnni Anderson and Martin, from the middle Miocene, is closely related page 359 Fig. 10. Lucina (Here) excarata Carpenter, specimen No. 133 S. D. S. N. H., from locality 217b, middle Pliocene of Holser Canyon, Los Angeles Co. Interior of right valve, length IS mm. . . . page 290 Figs. 11. Muconia planiuseula, new species, type. Recent specimen from Nunivak Isl., Alaska, labeled 301-1 A in the collectionat Stanford LTniversity. Fig. 11a, interior of right valve; fig. lib, interior of left valve, length 23.5 mm. The exteriors of this specimen are shown on jilate 20, figs. 8a, 8b jjage 372 Figs. 12. Tarax pariiis (Conrad), Recent specimen from San Ignacio Lagoon, Lower California, labeled 1657A in the collection at Stanford University. Fig. 12a, interior of right valve; fig. 12b, exterior of the same valve; length IS mm. When living, this species is known as sericatus (Reeve) page 295 Figs. 13. Semele derim (Conrad), specimen No. 137 S. D. S. N. H., from Los Cerritos, Signal Hill, San Pedro, upper Pleistocene. Fig. 13o, hinge of right valve; fig. 13b, exterior of the same valve; length 48 mm page 376 Figs. 14. Tarax orhellus (Gould), Recent specimen from San Diego, labeled 16.5S-3A in the collection at Stanford I'niversity. Fig. 14fl, interior of right hinge, x 2; fig. 14b, exterior of the same valve, natural size; length 25.5 mm. This is an unusually plump form, like the form aleuticus (Dall), the opposite extreme from siibe/uadratus (Carpenter) page 293 (Continued (in pai/e fill) Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA PlATE 14 Volume 1 1 PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 911 EXPLANATION OF PLATE 14— (Continued) Figs. 15. Lucina (Myrted) californica Conrad, specimen Xo. 13S S. D. .S. X. H., from the San Pedro Plei-stocene. Fig. 15o, interior of the right hinge; fig. 156, exterior of the same valve; length 44 mm page 285 Fig. 16. Rocheforlia tumida (Carpenter), Recent specimen labeled 68-4 in the collection at Stanford University', found in the gill cavity of the sand crab, Blepharipoda occidentalis, from Pismo, California. Interior of the left valve (note that the anterior extremity is the longer), X 3, length 6 mm page 301 Fig. 17. Rocheforlia iinnida (Carpenter), Recent specimen from the same lot as the last. Exterior of the right valve, x 3, length 5 mm. The dark material in the center of the hinge is liga- ment, not a tooth page 301 Fig. 18. Lucina {Mijrlea) nuttoUri Conrad, specimen No. 139 S. D. S. N. H., from locality 216, basal Pliocene east of Fernando Pass, Los Angeles Co. Exterior of right valve, length 14 mm. page 288 Figs. 19. Chironia suhorbicularis (Montagu) variety laperousii Deshayes, Recent specimen from Orcas Island, Puget Sound, labeled 65-2A in the collection at Stanford University. Fig. 19a, interior of the right hinge, x 2; fig. 196, exterior of the right valve, natural size; length 25 mm. The dark colored material in the center of the hinge is entirely ligament. There is no tooth nor hinge plate below it page 300 Figs. 20. Lucina (Millha) xantusi (Dall), .specimen No. 140 S. D. S. X. H., from locality 217[;, middle Pliocene of Holser Canyon, Los Angeles Co. Fig. 20o, interior of left hinge; fig. 206, exterior of left valve; length 59 mm page 291 Figs. 21. Lvcina (Myrtea) californica Conrad, specimen X'o. 142 S. D. S. X. H., from locality 101, upper Pliocene of Bath House Beach, .Santa Barbara. Fig, 21fl, hinge of left valve, x 2; fig. 216. exterior of the same valve; length 24.5 mm page 285 Figs. 22. Lucina (Myrtea) aculilineala Conrad, specimen No. 141 S. D. S. N. H., from the Pleistocene of San Pedro, Los Angeles Co. Fig. '22a, interior of left hinge; fig. 226, exterior of the same valve page 286 Fig. 23. Cumingia lamellosa Sowerby, specimen No. 143 S. D. S. N. H., from the upper Pliocene of locality 151, on Maria Ygnacia Creek about l.'o mi- northeast of Goleta, Santa Barbara Co. Interior of right hinge, x 2, length 23 mm. This specimen is also shown on plate 19, fig. 1 page 378 1 1 912 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE L5 Figs. 1. Dosinia poiulcrnsa (Gray), Recent specimen from San Ignacio Lagoon, Lower California, labeled 1893A in the collection at Stanford University. Fig. la, exterior of right valve; fig. 16, interior of right valve; fig. If, hinge of left valve; length 75 mm. This is a medium sized or small specimen. The species sometimes has more protruding umbones page 3.51 Figs. 2. Dosinia ponderosa (Gray) variety iocaKtosana Arnold, specimen No. 144 S. D. S. N. H., from locality 29, middle Pliocene of Balboa Park, San Diego. Fig. 2o, hinge of right valve; fig. 2b, exterior of the same valve; both views x ?3, length 122 mm page 352 Fig. 3. Dosinia ponderosa (Gray) variety jacalitosana Arnold, specimen No. 145 S. D. S. N. H., from locality 29, middle Pliocene of Balboa Park, San Diego. Hinge of left valve, x 73, length of specimen 102 mm. The dorsal margin is somewhat eroded page 352 Fig. 4. Dosinia ponderosa (Gray) variety longidens, new variety, type specimen. No. 146 S. D. S. N. H., from well core taken near Bakersfield, upper Miocene (possibly middle Miocene). Hinge of left valve showing elongate anterior tooth, length of specimen 72 mm. The drill has distorted this specimen, crushing somewhat the posterior dorsal margin and elongating the anterior; but the hinge plate is intact page 353 Fig. 5. Pscphidia lordi (Baird), Recent specimen from Friday Harbor, Paget Sovmd, labeled 232A in the collection at Stanford University. Ex-terior of left valve, X 3, length 6 mm. This species is sometimes relatively less elongate page 336 Fig. 6. Pscphidia lordi (Baird), specimen from the same lot as the specimen shown in fig. 5. Exterior of right valve, x 3, length 6.2 mm page 336 Figs. 7. Psephidia lordi (Baird), specimen from the same lot as the specimens shown in figs. 5 and 6. Fig. 7a, interior of right valve; fig. 76, interior of left valve; both views x 3, length 6.5 mm page 336 Figs. 8. TransenneUa tanlilla (Gould), Recent specimen from Monterey, California, labeled 235A in the collection at Stanford University. Fig. So, interior of right valve; fig. 86, interior of left valve; both views x 3, length 6 mm page 338 Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA PlATE 15 *\ 914 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 16 Figs. 1. Venns (Chione) succincta Valenciennes, specimen No. 147 S. D. S. N. H., from locality 97, upper Pleistocene (Palos Verdes) terrace about 5 mi. E. N. E. of the town of Newport Beach, Orange Co. Fig. la, interior of left valve; fig. 16, exterior of the left valve; length 48 mm. Four specimens of the left valve of this species, all from the same locality, are illustrated here to show the variation in form. The hinges vary as well as the shape and sculpture page 321 Figs. 2. Venus (Chione) suceincia Valenciennes, specimen No. 148 S. D. S. N. H., from the same lot as the specimen shown in figs. 1. Fig. 2a, interior of left valve; fig. 2b, exterior of left valve ; length 50 mm page 321 Fig. 3. ]'entis [Chione) succincta Valenciennes, specimen No. 149 S. D. S. N. H., from the same tot as the s))ecimens shown in figs. 1 and 2. Exterior of left valve, length 50 mm. This specimen is intermediate in shape between the specimens shown in figs. 1 and 2 page 321 F"iG. 4. Venus (Chione) suceincia Valenciennes, specimen No. 150 S. D. S. N. H., from the same lot as the specimens shown in figs. 1, 2, and 3. Exterior of left valve, length 42 mm. This is the variation commonly known as undatella; but it is not of significance page 321 Figs. 5. I'tJius (Chione) gnidia Broderip and Sowcrby, specimen No. Oil in the collection at Stanford University, from the Palos Verdes terrace, upjjer Pleistocene of San Diego. Fig. 5a, exterior of left valve; fig. 5fc, hinge of left valve; both views x ?-3, length 98 mm page 318 Figs. 6. Venus (Chione) elsmerensis (English), .specimen No. 151 S. D. S. N. H., from locality 202, lower Pliocene of Elsmere Canyon, Los Angeles Co. Fig. 6a, exterior of left valve; fig. 66, hinge view of left valve; length 75 mm. This specimen from the tyi^e locality of the species shows its close relationship with T'. gnidia page 319 Fig. 7. ]'cnus (Chione) elsmerensis (English), specimen No. 152 S. D. S. N. H., from the same locality as the specimen shown in figs. 6. Hinge of right valve, length 83 mm. + page 319 Volume I ] PLIOCENE AND PLEISTOCENE MoLLITSCA OF CALIFORNIA PlaTE 16 ^K^ 916 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 17 Fig. 1. Venus (Chione) srcuria Shimnird, tyjiical variety, s])ecimen No. 622 in the eollection at Stanford I'niversih', from the lower ^^'llllpat formation, probably lower Pliocene, but possibly upi)er Miocene, Scotia BlulTs, Humboldt Co., northern California. Exterior of left valve, length 8S mm page 320 Figs. 2. Venus (Chio)te) securis Shumard variety etisifera Dall, specimen No. 623 in the collection at Stanford l^niversity, from the Miocene 2 mi. south of Yaquina Bay, Oregon. Fig. 2«, exterior of left valve; fig. 2/), dorsal view showing hmule and escutcheon; length .50 mm, . ]iage 320 Fig. 3. Vinus {Chiorn-) securis Shumard variety ens^ifcra Dall, specimen No. 624 in the collection at Stanford University, from the same locality as the specimen shown in figs. 2. Exterior of left valve, length 45 mm page 320 Figs. 4. Venus (Chione) securis Shumard variety fcrnandoensis (English), specimen No. 159 S. D. S. N. H., from locality 209, lower Pliocene of Elsmere Canyon. Fig. 4a, exterior of left valve; fig. 46, dorsal view showing hmule and escutcheon; length 42 mm. The series of specimens shown in figs. 1 to 4 illustrates well the efTects of weathering. The hard cal- careous matrix was knocked from this one with a hammer, and the concentric lines as well as the boundary of the escutcheon are sharp. The lamellae, of course, remained in the matrix page 321 Fig. 5. Venus [Chione) securis Shumard variety fernajidoensis (English), specimen No. 160 S. D. S. N. H., from locality 206, lower Pliocene of Elsmere Canyon. Exterior of left valve, length 23 mm page 321 Fig. 6. W'lius (Chione) securis Shumard variety fcrnandoensis (English), young or stunted form, specimen No. 161 S. D. S. N. H., from locality 2C9, lower Pliocene of Elsmere Canyon. Exterior of left valve, length 13 nun : ]5age 321 Fig. 7. Aniiantis callosa (Conrad), specimen No. 162 S. D. S. N. H., from the middle Pliocene (San Diego zone) of locality 2176, Holser Canyon, Los Angeles Co. Exterior of left valve, length 41 nmi page 348 Figs. S. Amianlis callosa (Conrad) variety slalderi (Clark), specimen No. 164 S. D. S. N. H., from well core taken near Bakersfield, upper or possibly middle Miocene. Fig. 8a, hinge of ^ right valve, showing faintly the two close cardinal teeth; fig. 8b, exterior of right valve showing sculpture and general shape; length 28 mm page 349 Fig. 9. Aniiantis callosa (Conrad), .specimen No. 163 S. D. S. N. H., from the middle Pliocene of locality 214, west of Fernando Pass, Los Angeles Co. Exterior of right valve, length about 50 mm page 348 Figs. 10. Clenientia (Compsonryax) subdiaphana Carpenter, specimen No. 167 S. D. S. N. H., from the lower San Pedro, lower Pleistocene of Deadman Island, San Pedro Harbor. Fig. lOo, interior of right valve; fig. 106, exterior of right valve; length 40 mm page 334 Fig. 11. AmianUs callosa (Conrad), specimen No. 625 in the collection at Stanford University, from the Pleistocene of San Pedro. Hinge of left valve, length of specimen 77 mm I'age 348 Fig. 12. Antiantis callosa (Conrad), specimen No. 165 S. D. S. N. H., from locality 207, lower Pliocene of Elsmere Canyon, Los Angeles Co. Exterior of right valve, length of fragment 38 mm. It might be questioned that this identification is correct, as the specimen lacks the char- acteristic concentric ridges of callosa; but figs. 7 and 9 show what has happened page 348 Fig. 13. Amianlis callosa (Conrad), specimen No. 106 S. D. S. N. H., from the same locality as the specimen shown in fig. 12. Hinge of right valve, fragment natural size. This specimen, though partly smooth like the last, has part of the sculpture remaining. Back of the umbo the shell is 5 mm. thick page 348 Fig. 14. Amianlis callosa (Conrad), Recent specimen from San Diego, labeled 1S94-2A in the collection at Stanford University. Interior of right valve, length 82 mm page 348 Fig. 15. ? dementia (Compsomyax) suhdiapliana Carpenter, specimen No. 626 in the collection at Stanford University, from the U])per Pliocene (?) of Cape Blanco, Oregon. Exterior of right valve, length 63 mm. This form does not have the typical shape of C. subdiap)iana and may even be a Pilar, perhaps Conrad's Dione breviUneata. However, there is a similar Recent specimen in the collection at Stanford University that is surely no more than a variant of C. subdiaphana. The hinge is not exposed page 334 Volume I] PlIOCENE AND PLEISTOCENE :\IoLLUSCA OF CALIFORNIA PlATE 17 918 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE IS Figs. 1. Venerupis (Prolothaca) staminea (Conrad), specimen No. 153 S. D. S. N. H., from locality 40, upper Pleistocene terrace along beach southwest of Goleta. Fig. lo, interior of right valve; fig. 16, exterior of right valve; length 50 mm page 329 Figs. 2. Veneruins (Prolothaca) staminea (Conrad), specimen No. 154 S. D. S. N. H., from the same locality as the specimen shown in figs 1. Fig. 2a, interior of left valve; fig. 26, exterior of left valve; length 44 mm. This specimen is relatively shorter than the last, but like most of the variations of this species it is without significance page 329 Figs. 3. Vmervpis {Protothaca) staminea (Conrad) variety ruderala (Deshayes), specimen No. 155 S. D. S. N. H., from locality 74 near locality 40 where the specimens shown in figs. 1 and 2 came from. Fig. 3o, interior of right valve; fig. 36, exterior of right valve; length 51 mm. This specimen illuistrates the effect of the burrowing habit on both hinge and sculpture and shows how close the transition is to Ir\is page 331 Fig. 4. Saxidomus nuttnlli Conrad variety giganteiis (Deshayes), young, figured specimen No. 156 S. D. S. N. H., from locality 74, found with the specimen shown in figs. 3. Interior view of right valve, length 47 mm. This cold-water variety is distinguished iirincipally by its finer concentric scidptin-e page 342 Figs. 5. Irus lamdlifer (Conrad), Recent specimen from Monterey, labeled 1S06A in the collection at Stanford l^niversity. Fig. 5o, interior of right valve; fig. 56, exterior of the same valve; length (including protruding lamella) 27.5 mm page 332 Figs. 6. Irus lamdlijcr (Conrad), Recent specimen from Monterey, from the same lot us the specimen shown in figs. 5. Fig. 6a, interior of left valve; fig. 66, exterior of the same valve; length mm. This elongate specimen partially illustrates the variability of this burrowing species P-ige 332 FtG. 7. ]rus lamdlifer (Conrad) variety prelamrllifer, new variety, type. No. 157 S. D. S. N. H., from well core taken near Bakersfield, upper (i)ossibly middle) Miocene. Exterior of right valve, length 21 mm. This specimen illustrates the high, thin, widely spaced lamellae characteristic of this variety. The lamellae are thinner and more delicate than the figure shows page 332 Fig. 8. Ints lamellifer (Conrad), Recent specimen from the same lot as the specimens shown in figs. 5 and 6. Exterior of right valve, length 23 mm. This variation has a circular shape coniiianible to that of the variety prclamcllifer page 332 Figs. 9. Vcnei-upis (CaUithaca) tenerrima (Carpenter), sijecimen No. 620 in the collection at Stanford Lniversity from the Pales Verdes of San Pedro, upper Pleistocene. Fig. 9o, hinge of left valve; fig. 96, exterior of left valve; both views x rs, length 107 mm page 327 Fig. 10. Saxidomus uuttalli Conrad, specimen No, 15S S. D. S. N. H., from locality 101, upi)er Pliocene of Santa Barbara. Hinge of left valve, length of specimen 75 mm. The sculpture on the early part of this shell suggests that if might belong to the variety (ligauteus page 342 Fig. 11. Saxidomus uuttalli Conrad, specimen No. 621 in the collection at Stanford I'niversity, from Stanford University locality 206, Las Posas zone, lower Pleistocene, outcrojjping on the east bank of Barlow Cany(jn, Santa Paula Quadrangle, \'entura Co. Exterior of left valve, length 89 mm Page 341 Volume I] PlIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA PlATE 18 A.:i^'% wm\% r':. ' 920 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 19 Fig. 1. Cioiiiiigiii hniullosd Sowerby, specimen No. 143 8. D. S. X. H., from the upper Pliocene of locality 151. Exterior of right valve, length 23 mm. The hinge of this specimen is shown on plate 14, fig. 23 page 378 Fig. 2. Corbula (Lcntidium) luteola Carpenter, specimen No. 168 S. D. S. X*. H., from locality 78, a low, upper Pleistocene terrace south of 8eacliff Station, "\'cntura Co. Exterior of left valve, X 3, length 9.5 mm. When magnified this sjjecies is practically indistinguishable from C. fragilis. See also fig. 7 I'agc 421 Figs. 3. Tivela stuUonwi (Maw-e), young, specimen No. 170 S. D. S. N. H., from locality 99, tipi)er Pleistocene terrace west of Newport, Los Angeles Co. Fig. 3a, exterior of right valve, natural size; fig. 3b, interior of the same valve x 2; length 30 mm. Adults of this species often get very large and heavy. The species sometimes has a much smaller apical angle. See also fig. 8 page 340 Fig. 4. Corbula (Corbula) gibbiformis, new species, paratype, specimen No. 171 S. D. S. N. H., from a well core taken in the southwestern part of the San Joaquin basin, upper Etchegoin formation. Hinge of right valve, x 2, length 12 mm page 420 Fig. 5. Corbula (Corbula) gibbiformis, new species, type, specimen No. 172 S. D. S. N. H., foimil with the specimen shown in fig. 4. Exterior of right valve, x 2, length 13 mm page 420 Fig. 6. Corbula (Cwbula) gibbiformis, new species, paratype, specimen No. 173 S. D. S. X"". H., found with the other spec'mens of this species. E.xterior of the left valve with part of a right valve showing behind, x 2, length 12 mm. The sculpture of this valve contrasts strikingly wuth that of the other page 420 Fig. 7. Corbula (Lcntidium) luteola Carpenter, specimen Xo. 169 S. D. S. X. H., from the same locality as the specimen shown in fig. 2. Interior of the left valve, x 3, length 8.5 mm page 421 Fig. 8. Tivela slultorum (Mawe), reproduction of Mawe's original figure. The reproduction is the same size as the original, but the writers do not know whether Mawe's original was natural size or not page 340 Fig. 9. Lsemcardium (Nemocardium) centifilosum (Carpenter), specimen Xo. 174 S. D. S. X'. H., found with Corbula gibbiformis, upper Etchegoin. Exterior of right valve, length 18 mm. This species is more circular in outline and has stronger radials than the young of Lsevicardium elalum page 311 Fig. 10. Lsevicardium (Nemocardium) centifilosum (Carpenter), specimen Xo. 175 S. D. S. X. H., fotind with the specimen shown in fig. 9. Exterior of right valve, length 18 mm page 311 Fig. 11. Lsevicardium. (Cerastoderrna) ciliatum (Fabrieius), Recent specimen from Bering Sea, labeled 42SA in the collection at Stanford L'niversity. Exterior of left valve, length 50 mm. . . . page 310 Fig. 12. Lsevicardium (Cerastoderma) decoralum (Grcwingk), specimen X'"o. 627 in the collection at Stanford University, from the upper Pliocene or Pleistocene of Elk River, Oregon. Exterior of left valve, length 23 mm page 308 Fig. 13. Lseidcardium (Cerastoderma) californiense (Deshayes), Recent specimen from Griffin Bay, San Juan Island, Puget Sound, labeled 250-lA in the collection at Stanford I'niversity. Exterior of left valve, length 44 mm page 309 Fig. 14. Lxvicardium (Cerastoderma) corhis (Martyn), reproduction of Martyn's original figure, reduced to half the size of Martyn's excellent drawing page 307 Fig. 15. Lsricordium. (Trachycardium) quadrageuarium (Conrad), young Recent specimen from San Diego, labeled 1614A in the collection at Stanford I'niversity. Exterior of left valve, length 44 mm page 306 Fig. 16. Lxvicardium (Cerastoderma) californiense Deshayes, Recent specimen from .Vmaknak Island, ITnalaska Group, Alaska, labeled A in the collection at Stanford University. Exterior of left valve, length 68 mm. This coarse, northern form contrasts strikingly with the Puget Sound form shown in fig. 13, but the differences are due entirely to the environment .... page 309 Fig. 17. Lxvicardium (Cerastoderma) corbis (Martyn), Recent specimen from Seven Mile Beach, middle California, No. 176 S. D. S. X. H. Exterior of right valve, length 69 mm page 307 VoLrME I ] Pliocene and Pleistocene AIollusca of California Plate 19 922 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 20 Figs. 1. Maaumi nirUiltcnsix Whiteaves, Recent specimen from the type locality, loaned by the Museum of the Canadian Geological Survey at Ottawa. Fig. lo, exterior of right valve; fig. \b, exterior of left valve, natural size. This species has usually been known under its synonym mflatula Dall page 372 Figs. 2. Macoma carJntlensis Whiteaves, Recent specimen from British Columbia, loaned by the Museum of the Canadian Geological Survey at Ottawa. Fig. 2o, exterior of right valve; fig. 2/), exterior of left valve, natural size. The forms shown in figs. I and 2 occur together and grade into each other completely page 372 Fig. 3. Macoma moesla (Deshayes), reproduction of Ball's original figure of M. krausei Dall, from Icy Cape, Arctic Ocean. Exterior of right valve, length 23 mm. M. krausei was later admitted by Dall to be a synonym of moesta page 370 Figs. 4. Macoma moesla (Deshayes) variety acolasta Dall, reproduction of Dall's original figures. Fig. 4a, exterior of right valve; fig. 46, interior of left valve; natural size. These illustra- tions show how close this variety is to the typical form page 371 Fig. 5. Macoma inquinala (Deshayes), reproduction of Reeve's figure of this species, Conch. Icon., Vol. 17, Tellina, pi. 30, species 164, 1867, Recent, Vancouver Island. Exterior of left valve, natural size. This species is very variable in shape page 307 Figs. 6. Macoma secta (Conrad), specimen No. 177 S. D. S. N. H., from locality 2176, middle Pliocene of Holscr Canyon, north of the Santa Clara Valley, Los Angeles Co. Fig. 6a, exterior of left valve; fig. 66, exterior of right valve; length 53 mm. This common species is probably reported sometimes as nasuta or other sjiecies, for as a fossil it loses some of its characteristic appearance page 374 Figs. 7. Macoma balthica (Linnaeus), young, specimen No. 134 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. Fig. 7a, exterior of right valve; fig. 76, exterior of left valve; length 13. .5 nnn. The interiors of this specimen are shown on plate 14, figs. 6a, 66 page 371 Figs. 8. Macoma plnniuscula, new species, type, Recent specimen from Nunivak Island, Alaska, labeled 301-lA in the collection at Stanford University. Fig. 8a, exterior of right valve; fig. 86, exterior of left valve, length 23.5 mm. The 'nteriors of this specimen are shown on plate 14, figs. 11a, 116. The species is rather variable in shape, but retains its flat- tened, polished aspect. It may be a variety of hallhica. It is less closely related to the true carlottensis page 372 Figs. 9. Tellina mcrojuiis Dall, Recent specimen from San Diego, labeled 277A in the collection at Stanford University. Fig. 9a, exterior of left valve; fig. 96, exterior of right valve. The interiors of this specimen are shown on plate 14, figs. 9a, 96 page 359 Fig. 10. Macoma moesta (Deshayes) variety acolasta Dall, sjjecimen No. 135 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of tJoleta, Santa Barbara Co. Exterior of right valve, length 20 mm. The interior of this specimen is shown on plate 14, fig. 7. Compare also figs. 3 and 4 of this plate page 371 Figs. 11. Macoma nasuta (Conrad), specimen No. 178 S. D. S. N. H., from locality 74, found with the specimen shown in fig. 10. Fig. Ua, exterior of right valve; fig. 116, interior of the same valve; length 53 mm. This species has an unusually heavy hinge for a Macoma page 305 Fig. 12. Tellina idic Dall, specimen No. 179 S. D. S. N. H., from locality 214, middle Pliocene over the Newhall railroad tunnel, Los Angeles Co. Exterior of imperfect left valve, length 52 mm. The sculpture remaining in patches on the other valve is as .strong as on the specimen shown in fig. 14o page 358 Fig. 13. Tellina bodegensis Hinds, specimen No. 180 S. D. S. N. H., from locality 99, upper Pleistocene terrace west of Newport, Los Angeles Co. Exterior of right valve, length 47 mm page 362 Figs. 14. Tellina id.r Dall, specimen No. 628 in the collection at Stanford University, from the upper San Pedro of Santa Monica. Fig. 14a, exterior of right valve; fig. 146, interior of right valve; length 58 mm. The other valve has fine concentric lines as shown in fig. 12 page 358 Figs. 15. Sanguinolaria niittallii Conrad, specimen No. 629 in the collection at Stanford University, from the Pleistocene of San Pedro (Arnold Collection). Fig. 15a, hinge of left valve; fig. 156, exterior of left valve; length 88 mm page 383 I'ig. 16. Aj}ohjmetis biangulata (Carpenter), specimen No. 630 in the collection at Stanford University, from Stanford LTniversity locality 206, Las Posas zone, lower Pleistocene, of Barlow Canyon, Wntura Co. Exterior of right valve, length 72 mm page 363 Volume I] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA PlATE 20 19a ./ 924 San Diego Society of Natural History [Memoirs EXPLAXATIOX OF PLATE 21 Fig. 1. S'iliqiia alia (Broderip and Sowerby), Recent specimen from Swikshak Beach, Alaska, labeled 469A in the collection at Stanford University. Entire interior of the right valve and ]iart of the left, x %, length 118 mm page 388 Figs. 2. 7\igehis califoniianus (Conrad), specimen No. 181 S. D. S. N. H., from the San Pedro Pleisto- cene (Arnold Collection). Fig. 2a, exterior of left valve; fig. 26, interior of left valve; length 78 mm. The pallia! sinus can be seen reaching two-fifths of the length of the sliell page 384 Fig. 3. Tagchis califoniiatius (Conrad), specimen No. 182 S. D. S. N. H., from the San Pedro Pleisto- cene (Arnold Collection). Interior of right valve, length 76 mm page 384 Fig. 4. Solen sicarius Gould, specimen No. 183 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. Interior of right valve, length 62 mm. The small, somewhat bifid tooth is scarcely visible at the extreme end page 385 Fig. 5. Gari Khntida (Gabb), Recent specimen from San Pedro (25 fathoms), labeled 145A in the collection at Stanford University. Exterior of left valve, x %, length 138 mm page 382 Fig. 6. Siliqua lurida (Conrad), specimen No. 184 S. D. S. N. H., from the middle or upper Etchegoin of the General Petroleum Corp. Stiles well near McFarland, Kern Co., depth 3000-18 feet. Exterior of right valve, length 36 mm page 389 Fig. 7. Cryptoniija californica (Conrad), .specimen No. 185 S. D. S. X. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. Exterior of right valve, length 23 mm page 417 Fig.s. 8. Crijiitomya californica (Conrad), Recent specimen from San Diego, labeled 1707A in the col- lection at Stanford University. Fig. Sa, exterior of left valve; fig. 86, interior of the same valve tipped up to show the chondropliore; length 25 mm liage 417 Fig. 9. Siliqua cf. palitla (Dixon), specimen No. 186 S. D. S. N. H., from the lower Etchegoin of the General Petroleum Corp. Stiles well near McFarland, Kern Co., depth 4450-68 feet. Exterior of left valve, partial length 42 mm. Tlie internal rib can be clearly seen. This form is too large for lucida, but is not characteristic of patula. The rib is too narrow for patula or (dia and goes too straight across for patula. The shape is not right for alia. This form is much like the Atlantic nahanlensis, which may have to be recognized in the California Pliocene pages 387, 388 Figs. 10. Panopc (Panomya) ampla (Dall), Recent specimen collected off Orcas Island, Puget Sound, ^\'ashington, labeled 198-2A in the collection at Stanford University. Fig. 10a, hinge of right valve; fig. 106, exterior of right valve; length 60 mm page 426 Fig. 11. Cryploinya californica (Conrad), specimen No. 315 S. D. S. N. H., from the Las Posas zone, lower Pleistocene, of Barlow Canyon, A'entvu'a Co. Exterior of left valve, with the hinge of the right valve, which lacks the chondrophore, showing beliind; length 28 mm page 417 Figs. 12. Panopc (Panope) gcnerosa Gould, specimen No. 187 S. D. S. X". H., from locality 74, ujiper Pleistocene terrace southwest of Goleta, Santa Barbara County. Fig. 12a, exterior of left valve; fig. 126, interior of the same valve; both views x %, length 102 mm. This is not a full grown specimen page 424 Fig. 13. il/i/a (Mya) arenaria Linnreus variet}' japonica Jay, specimen No. 188 S. D. S. N. H., from the upper Etchegoin in the So. Calif. Gas Co. well No. 1-4, Sec. 4, T. 28 S., R. 23 E., Kern Co., depth 2877 feet. Exterior of the right valve, with part of the posterior end missing; partial length 70 mm page 412 Figs. 14. Ciyplomya californica (Conrad), Recent specimen from the same lot as the specimen shown in figs. 8. Fig. 14o, exterior of right valve; fig. 146, exterior of left valve; length 16 mm. This variation is very common. It has the shape of the form often called oralis page 417 Volume I ] PlIOCENE AND PLEISTOCENE MOLLLTSCA OF CALIFORNIA PlATE 21 926 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 22 Fig. 1. Dosinia longula Conrad, holotype, specimen No. 1.3343 in the U. S. National Museum, from the Miocene of the Salinas Valley, Monterey Co. Exterior of left valve, natural size. . . page 354 Fig. 2. Anatina {Ra'eta ?) transmontana (Conrad), holotype, specimen No. 13322 in the U. S. National Museum, from "Rancho Triumpho," Los Angeles Co. (near the boundary of Ventura Co. ?), probably Temblor, lower middle Miocene. Exterior of right valve, natural size . . page 409 Fk;. 3. Dosinia iiionta7ia Conrad, holotype, specimen No. 13357 in the U. S. National Museum, from the Miocene of the Salinas Valley, Monterey Co. Exterior of left valve, natural size .... page 354 Fig. 4. Dosinia suhobliqua Conrad, holotype, specimen No. 13356 in the U. S. National Museum, from the Miocene of the Salinas Valley, Monterey Co. Exterior of right valve, natural size page 354 Fig. 5. Peden {Patinopeclen) jtropalnlus Conrad, holotype, No. 3504 in the U. S. National Museum, from the Miocene of Astoria, Oregon. Exterior of right valve, natural size. The outer surface of this specimen is worn away, but the 16-17 slightly sulcated ribs and the general shape can be seen page 192 Figs. 6. Schizothcerus m/ltallii (Conrad) variety ijajaroatius (Conrad), specimen No. 330 S. D. S. N. H., from the Purisima formation, lower or middle Pliocene, at Point .\no Nuevo, San Mateo Co. Fig. 6a, posterior view showing the ga]5e; fig. 6b, exterior of left valve; length 85 mm . . page 405 Figs. 7. Macira (Mulinia) pallida Broderip and Sowerby, Recent specimen from Ecuador, labeled A in the collection at Stanford University. Fig. 7a, hinge of right valve; fig. 7b, exterior of right valve; fig. 7c, dorsal view of right valve; length 60 mm. The dorsal margin of the shell is not broken by a ligamental slit, though the shell wall becomes thinner back of the ligament and in jioorly preserved specimens may be broken away. The ligament and resiliura are both internal, and there is no small shelly ridge separating them as in t>^3ical Mactra or Mactrclla page 400 Fig. 8. Schisothserus nuUallii (Conrad) variety pajaroanus (Conrad), holotype, specimen No. 13318 in the V. S. National Museum, from "Pajaro River, Santa Cruz," probably Pliocene. Exterior of right valve, natural size. The shape of this specimen is badly obscured by erosion page 405 Fig. 9. ScJiizotlisrus nuilallii (Conrad), tyjiical variety. Recent specimen, No. 331 S. D. S. N. H., from Totten Inlet, Puget Sound. Posterior view showing the gape, x yi, length of specimen 147 mm., height 115 mm. This figure is to be compared with fig. 6a. Other illustrations of this species are given on plate 23, figs. 8a, 86, 9 page 404 Figs. 10. Mactrella exoleta (Gray), Recent specimen from the coast of Guerero, Mexico, 15 miles south of Rio Balsas, labeled 866-3A in the collection at Stanford University. Fig. 10a, right hinge; fig. 10b, exterior of right valve; x %, length 118 mm. The shape is somewhat similar to that of Mactra (Mulinia) pallida, but the hinge is very different, showing the shelly ridge separating the ligament from the resilium and also showing the weak posterior laminae. In spite of the shelly ridge, Maclrdla is j^robably more distinct from Macira than are Mulinia and Spisula page 402 Volume I] PLIOCENE AND PLEISTOCENE AIoLLUSCA OF CALIFORNIA PlATE 22 928 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 23 Figs. 1. Analiim (Racta) plicatella (Lamarck), variety longior, new variety, ty])e, speoimen No. 192 S. D. S. N. H., from the upper (jiossibly middle) Miocene of the Siijierior Oil Comixmy's Ansolabehere well No. 1, northwest of Baker.sfield, depth 4525 feet. Fig. la, e.xterior of left valve; fig. 16, hinge of the same valve; length 40 mm page 408 Figs. 2. Mactra (Mactra) orthomorpha, new species, type, specimen No. 193 S. D. S. N. H., from the upper Etchegoin of a well drilled for oil near Tipton, Tulare Co. Fig. 2a, exterior of right valve; fig. 2b, same view with a fragment of another specimen of about the same size fitted over it to indicate the shape; fig. 2f, hinge of the right valve; partial length 36 mm., restored 39 mm. The shelly ridge of typical Maclra is faintly visible above and to the right of the chondrophore IJage 391 Figs. 3. Mactra (Spisida) albaria Conrad, specimen No. 189 S. D. S. N. H., from a depth of 4575 feet in the same well in w'hich the specimen shown in fig. 1 was found, upper (possibly middle) Miocene. Fig. 3a, exterior of right valve; fig. 36, hinge of the same valve; length 30 mm . . page 395 Fig. 4. Mactra (Spisula) calilliformis (Conrad), specimen No. 196 S. D. S. N. H., from the Crijptomya californica zone, lower Etchegoin, of the Petroleum Eastern Production Company's well K. C. L.-B. No. 3, Fr\iitvale district, northwest of Bakersfield, depth 3229 feet. Exterior of right valve, length 58 mm. The beaks of this specimen are crushed forward and pointed, as is often the case with well-core sjieciniens. The posterior is slightly broader than shown in the illustration page 398 Figs. 5. Anatina (Ra'eta) undulata (Gould), specimen No. (531 in the collection at Stanford I^niversity, from the Palos Verdes terrace at San Pedro, upjjcr Pleistocene. Fig. 5a, exterior of left valve; fig. 5b, hinge of right valve; fig. 5(', hinge of left valve; length 80 mm page 407 Fig. 6. Mactra {Maclra) orttiotiiorpha, new species, paratype. No. 194 S. D. S. N. H,, found with the type. Hinge of left valve, length 21 mm. This specimen and the one shown in fig. 7 illustrate the single long thin laterals of the left valve. The mactroid ridge hardly shows on the specimens and is not visible in the illustrations page 391 Fig. 7. Mactra (Mactra) orthoinnrpha, new si>ecies, paratyj^e. No. 195 S. D. S. N. H., foimd with the type. Hinge of left valve, length about 21 mm page 391 Figs. 8. Schizotha;rus uuttallii (Conrad), specimen No. 198 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. Fig. 8a, hinge of right valve; fig. 8b, exterior of right valve; length 128 ram page 404 Fig. 9. Schizollistrus nullalUi (Conrad), specimen No. 199 S. D. S. N. H., from the same locality as the last. Hinge of left valve, length of specimen 96 mm. The ]iosterior gape of this species is shown on plate 22, fig. 9 page 404 Fig. 10. Mactra (Spisula) catillifornds (Conrad), specimen No. 197 S. D. S. N. H., from the same well as the specimen shown in fig. 4, depth 3230 feet. Hinge of large right valve, fragment shown 52 mm. long page 398 Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA PlATE 23 -'«S'%i 4f) 930 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 24 Figs. 1. I'hulmlkka {I'huladidea) pcnita (Conrad), specimen No. 2U0 W. D. .S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. Fig. la, exterior of left valve; fig. 16, interior of left valve; length 81 mm. This species when young has the shajje of a Pholas. It is not unlikely that the separation between Pholadidea and Pholas has been overemphasized Jiage 434 Fig. 2. Pholas iZirfxa) gabbi (Tryon), specimen No. 201 S. D. S. N. H., from the middle Etchegoin of the General Petroleum Corp. Stiles well No. I near McFarland, Kern Co., California, depth 3900-18 feet. Exterior of right valve, length 66 mm page 432 Figs. 3. Mya {Platyodon) canceUata Conrad, specimen No. 202 S. D. S. N. H., from locality 40, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co. Fig. 3a, hinge and interior of left valve; fig. 3b, exterior of left valve; length .56 mm l)age 415 Fig. 4. Bankia sclacea (Tryon), Recent specimen from Departure Bay, British Columbia, labeled 386-4A in the collection at Stanford University. Fragment of the tube secreted by the animal, length 80 mm. The shell of this species, found in Recent specimens within the tube, resembles a very small, thin, shortened Pholad. Bankia is distinguished from Teredo only by accessory semi-hard parts Not in text Fig. 5. Aletes squamigerus Carpenter, variety pennalus (Morch), specimen so identified and reported by Mr. T. S. Oldroyd from the lower San Pedro series (i. e., San Pedro formation) of the Nob Hill cut, San Pedro; specimen in the collection at Stanford L'niversity marked 1.5.5A, length 79 mm. The typical variety of this species as identified by Mr. Oldroyd has rough longitudinal striations. This form might easily be mistaken for a Teredo tube such as shown in fig. 4; but it is a gastropod related to Vermdus, Serpulorbis, and Siliquaria. As most of the distinctions in this group depend on opereula, it is obvious that identifications of fossils are usually very uncertain. The occasional shelly partition, one of which is shown in the photograph, will sometimes help to distinguish this group from Teredo tubes jjage 777 Fig. 6. Cerilhidea californica (Haldemann), specimen N(j. 203 S. D. S. N. H., from the Pleistocene of San Pedro; length 24 mm l^age 763 Fig. 7. Cerilhidea californica (Haldemann), specimen No. 204 S. D. S. N. H., from the Pleistocene of San Pedro; length 29 mm page 763 Fig. 8. Billium (Semihitliitm) rugatum Carpenter, specimen No. 20.5 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co.; x 2, length 10 mm. . page 762 Fig. 9. Billium (Slylidium) eschrichtii (Middendorff), Recent specimen from Oregon or Washington, labeled 108-3A in the collection at Stanfortl University; X 2, length 14 mm page 761 Fig. 10. Olii'ella j)edroana (Conrad), specimen No. 206 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co.; length 11 mm. L'nfortunately the apex of the figure was trimmed off during the preparation of the plate page 626 Fig. II. "Cerilhiiim" simjAicius, new species, type. No. 207 S. D. S. N. H., from the middle Pliocene of locality 2176, Holser Canyon, north of the Santa Clara Valley, Los Angeles Co.; length of incomplete specimen 32 mm page 7.57 Fig. 12. Acleon. {Riela.ria) painei Dall variety grandior, new variety, type. No. 208 S. D. S. N. H., from the middle Pliocene of locality 217t-; length 18 mm page 444 Fig. 13. Relusa (Acteocina) ndcitella (Gould), specimen No. 209 S. D. S. N. H., from the Las Posas zone, lower Pleistocene of Harmon Canyon, Ventura Co.; length of incomplete specimen 19 mm page 447 Fig. 14. Billium (Lirohillium) asperum (Gabb) variety dikiUilnm, new variety, type. No. 210 S. D. S. N. H., from locality 2176, middle Pliocene of Holser Canyon, north of the Santa Clara Valley, Los Angeles Co.; x o, length of somewhat incomjjlete specimen 6 mm page 760 Fig. 1.5. Oliiiella biplicala (Sowerby), specimen No. 21 1 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara County; length 26 mm page 625 (Continued on page 9SS) Volume I ] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA PlATE 24 Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA 933 EXPLANATION OF PLATE 2-1— (Continued) Fig. 16. Mdanipiit: olivaceous Carpenter, specimen No. 212 S. D. S. N. H., from the upper San Pedro (Palos Verdes) of San Pedro; lengtli 13 mm. The plications jiresent on both li])s are not clearly shown page 461 Fig. 17. Hyalina (Cystiscus) jeweUii (Carpenter), specimen No. 213 S. D. S. N. H., from th(> lower San Pedro series of San Pedro, lower Pleistocene; x 5, length 5 mm. This specimen was picked at random from a lot identified by Mr. Oldroyd as nanella. The lower three plications are strong, the fourth barely visible in the photograiih, and the ui)per ones hardly discernible under a glass, as in the living jeircUii page 030 Fig. 18. Tcrchra (Sirioterebrum) alhocincla (Carpenter) variety pedroana Dall, Recent sjiecimen from San Diego, labeled 2133A in the collection at Stanford University; length 22 nun. This specimen belongs to the variation with weaker nodes on the anal fasciole page 469 Fig. 19. Terebra (Striotercbriim) cf. dislocata (Say), specimen No. 214 S. D. S. N. H., from locality 249, lower Pleistocene about a third of a mile north of the corner of Kalorama and Poli Streets in the city of Ventura, Calif.; length 2.5 mm. The reiiroduetion of this figure is poor. The axial ribs are nearly as strong as the elongate nodes on the anal fasciole. In albocincta variety pedroana the axial ribs are usually not so strong as on this specimen; and in the few cases where they are, the nodes on the anal fasciole are much stronger page 46S Fig. 20, Epilonium (Opalia) raricoslalvm (Stearns), specimen No. 215 S. D. S. N. H., from the middle Pliocene of Pacific Beach, San Diego; length 30 mm. (spire defective) page 853 Fig. 21. Conus californicua Hinds, specimen No. 216 S. D. S. N. H., from the Las Posas zone, lower Pleistocene of locality 235, Santa Paula Quadrangle, Ventura Co. ; length 33 mm page 472 Fig. 22. TurrileUa ranvlecki Arnold, specimen No. 217 S. D. S. N. H., from the middle Pliocene of locality 217a, Holser Canyon north of Santa Clara Valley, Los Angeles Co.; length of incomplete specimen 26 mm. This specimen shows the characters of the species more clearly than the specimens hitherto illustrated. Sometimes the central ridge is not so prominent page 773 Fig. 23. TurhoniUa (Pyrgolampros) idae Oldroyd, specimen No. 316 S. D. S. N. H., from locality 247, a little north of locality 249 (see fig. 19), lower Pleistocene of Ventura Co.; x 3, length 7 mm page 869 Fig. 24. Terebra (Strioterebrum) albocincta (Carpenter) variety pedroana Dall, Recent specimen from the same lot as the specimen shown in fig. 18; length 22 mm. This specimen is a more strongly sculptured variation page 469 Fig. 25. Odoslomia cf. (Evalea) phaiica Dall and Bartsch, specimen No. 21S S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co,; x 3, length 4.5 mm. This is a young specimen. A larger specimen perhaps of the same .species is shown on plate 32, fig. 20 page 875 Fig.s. 26, 27. Tiirritella jewettii Carpenter, specimens Nos. 219 and 220 S, D, S, N. H., from the lower San Pedro of San Pedro, lower Pleistocene; lengths 70 mm. and 49 mm., respectively. . . . page 770 Figs. 28-34. TurrileUa cooperi Carjienter, specimens Nos. 221 to 227 S. D. S. N. H., from the uiijier San Pedro series (Palos Verdes), upper Pleistocene of Crawfish George's, San Pedro; lengths 44 mm., 42 mm,, 35 mm,, 42 mm,, 47 mm,, 47 mm., and 42 mm,, respectively. This series of specimens, all from a single locality, is shown to illustrate the variability of this species. The specimen shown in fig. 28 has stronger ribs like tlie form described bj' Dall as riiariana. T. jeweltii has a wider apical angle page 771 934 San Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 25 Figs. 1. SurculUes (Pseudotoma) intortiis (Brocchi), specimen No. 632 in the collection at Stanford University, from the Scaldisien Pliocene of Antwerp, Belgium. Specimen apparently identified by Cossmann. Fig. la, apertural view, outer lip slightly defective; fig. lb, side view showing the nature of the posterior notch by the growth lines; length 62 mm . . . page 500 Fig. 2. SurcidUes (SurcuUtes) wynootcheensis (Weaver), specimen No. 633 in the collection at Stanford University, from the Miocene of Black Creek Bluffs, Wynootche River, Washington; length 44.5 mm. It is well to compare this member of the typical subgenus with what appear to be the derivatives of the typical subgenus figured on each side of it pages 493, 500 Fig. 3. SurcidUes (Megasumda) carpenlerianus (Gabb) variety cooperi (.'\rnold), type, specimen No. 426 in the collection at Stanford University; length 64 mm page 499 Figs. 4. SiircidUes [Megasurcula) carpenlerianus (Gabb), typical variety, specimen No. 228 S. D. S. N. H., from Stanford University locality 643, Las Posas zone east of Sexton Canyon, \'entura Co.; length 63 mm page 497 Fig. 5. SurcidUes (Megasurcula) remondii (Gabb), specimen No. 229 S. D. S. N. H., from the lower Pliocene of locality 216 east of Fernando Pa.ss, Los Angeles Co.; length 40 mm page 495 Fig. 6. SurculUes (Megasurcula) remondii (Gabb), specimen No. 230 S. D. S. N. H., found with the specimen shown in fig. 5; length 35 mm page 495 Fig. 7. Surculites (Megasurcula) remondii (Gabb), specimen No. 634 in the collection at Stanford University, from Elsmere Canyon, northeast of Fernando Pass, Los Angeles Co.; length 30 mm page 495 Figs. 8. SurculUes (Megasurcula) remondii (Gabb), Recent specimen from San Pedro, labeled 550A in the collection at Stanford University; length 35.5 mm. This specimen has an oper- culum with a terminal nucleus. It is more like the Pliocene type specimen of this species in shape than are the specimens shown in figs. 5, 6, and 7, which are more like the form fernandoinus (Arnold) page 495 Figs. 9. Turricula flammea Schumacher, tyjje species of the genus Turricula, Recent specimen from Ceylon, labeled 3857A in the collection at Stanford University; length 72 mm page 486 Figs. 10. Clamlula (Kncfastia) luberculifera (Broderip and Sowerby), Recent specimen from the Gulf of California, labeled 717A in the collection at Stanford University; length 61 mm. The form shown in figs. 15 may be a more common variety of this species page 485 Figs. 11. Turricula maculosa (Sowerby), Recent specimen from the Gulf of California, labeled 720A in the collection at Stanford University; length 36 mm. This is an e.xtreme form for the geims Turricula leaning towards Spirotropis page 488 Figs. 12. Perrona nijal (Adanson in Bruguiere), type of the group Pusionella Gray, a minor subdivision of Perrona, Recent specimen from Corsica, labeled 342 lA in the collection at Stanford University; length 52 mm. This species is figured here to illustrate the smooth-whorled, shallow-notched extreme of the Clavatula-Perrona series page 612 Figs. 13. Perrona obesa (Reeve), a more typical species of Perrona, Recent specimen from Gambia, north- west Africa, labeled 3581A in the collection at Stanford University; length 36 mm page 612 Figs. 14. Clavatula (Clavalula) coronata (Chemnitz) Lamarck, variety bimarginala (Lamarck), Recent specimen from Goree, west Africa, labeled 3840A in tlie collection at Stanford University; length 47 mm. This is a variety of the type species of the genus Clavatula, showing the relationship with the subgenus Knefaslia pages 483, 484 Figs. 15. Clamlula (Knefaslia) olivacea (Sowerby), Recent specimen from the Gulf of California, labeled 716A in the collection at Stanford University; length 51 mm page 484 Figs. 16. Clavalula (Clavalula) coronata (Chemnitz) Lamarck, typical variety, Recent specimen from southern Africa, labeled 703A in the collection at Stanford University; length 29 mm. This is the type species of the genus Clavalula pages 482, 484 (Coidinued on page 937) Volume I] PLIOCENE AND PLEISTOCENE MoLLUSCA OF CALIFORNIA PlATE 25 Volume I ] PLIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 937 EXPLANATION OF PLATE 25— (Continued) Fig. 17. Genota mitriformis (Wood), Recent specimen from Senegal, northwest Africa, labeled .361oA in the collection at Stanford I'niversity; length .32 mm. This species is the tj^pe of Genota page 502 Fici. IS. MangcUa striolata Risso [ = .1/. ulitnuala (Montagu)l, reproduction of Risso's original figure, pi. 8, fig. 101, of the type species of AfanjeKa, from the Mediterranean; x Vo, length as indicated by Risso 13 mm page 5S.5 Pigs. 19. Mimgelia villiersii (Michaud) [ = M. alknuata (Montagu)], reproduction of Kiener's figures of PU'uroloma viUicrsii Michaud, from the Mediterranean; slightly enlarged according to Kiener's measurement, 7 lines ( = 18 mm.) page 585 Fig. 20. Lora oldroydi (Arnold) [ = :' Lorn decliris (Lovcn) variety icarinala (Sars)], type specimen. No. 429 in the collection at Stanford University, from the lower San Pedro series, lower Pleistocene of San Pedro, Calif. ; x 2, length 16 mm page 530 Fig. 21. Itil,nula rtunardiana (Risso), reproduction of Risso's original figure, x 2, length indicated by Risso 15 mm page 593 Fig. 22. Mattgelia (Mitromorpha) gracilior (Hemphill in Tryon), Recent specimen from Monterey in the Oldroyd collection at Stanford University, labeled 546A (lower left-hand corner of box); X 5, length 5.5 mm. This specimen may be part of the original type material; and if so, it shall be considered the lectotype. It is not unlikely that the names gracilior and intermedia should be both submerged into the synonymy of intcrfossa page 597 Fig. 23. DaphneUa clathrata Gabb, Recent specimen from San Pedro, labeled 461.4 in the collection at Stanford University; x 5, length S.2 mm page 542 Fig. 24. DaphneUa clathrata Gabb, specimen from the same lot as the specimen shown in fig. 23; x 5, length 10.75 mm page 542 938 San Diego Society of Natural History [Memoiks EXPLANATION OF PLATE 26 Fig. 1 Claeiis (Claims) flainmulalus Montfort, re])rodiictiou of one of Kiener's figures of Fkurotoma cchinata Lamarck; length according to Kiener 21 lines ( = 52 mm.)- H by any chance this is not the species figured by Montfort for the type of Clavus, it certainly has all the essential characters of that species and will represent the genotype page .574 Figs. 2. Claims (Claims) unimandatus (Sowerby), Recent specimen from the Gulf of California, labeled 699A in the collection at Stanford University; length 50 mm page 575 Figs. 3. Clavus (Clathrodrillia) gibbosus (von Born), reproduction of von Bern's original figures in the Testacea, reproduction natural size, original specimen given as 1 poll, 10 lines long ( = about 50 mm.) page 579 Figs. 4. Clavus (Clathrodrillia) flaridulus (Lamarck), Recent specimen from Hong Kong, labeled 3131A in the collection at Stanford University, length 57 mm. The oijerculum has a terminal nucleus page 579 Figs. 5. Pseudomelatoma penicillata (Carpenter), Recent specimen from Point Abreojos, Lower Cali- fornia, labeled 429-lA in the collection at Stanford University; length 33 mm. The opercuhmi with a terminal nucleus is visible in fig. 5a. Fig. 56 shows the side view and the shape of the posterior notch page 560 Figs. 6. Clavus (Crassispira) boilx (Valenciennes in Kiener), reproduction of Kiener's original figures of a specimen from Mazatlan, reproduction natural size; length according to Kiener 22 lines ( = about 54 mm.). It is highly desirable that specimens from Mazatlan be identified with these figures, unless Kiener made a mistake in locality page 580 Fig. 7. Claims (Cijmatosijririx) lunatus (Leal, reproduction of Lea's original figure, Miocene of Vir- ginia; reproduction natural size. This figure and figs. 3 show that Clathrodrillia is scarcely to be distinguished from C ymatosijrmx page 575 Fig. 8. Clavus (Cymalosyrinx) hemphilli (Stearns), Recent specimen from Scammon's Lagoon, Lower California, labeled 439 in the collection at Stanford University; x 2, length 12 mm. This species has been divided up into a large number of forms that are certainly no more than varieties and are probably of no significance page 577 Fig. 9. Claims (Crassispira) montere-ijensis (Stearns), Recent specimen from San Diego, labeled 436 in the collection at Stanford LTniversity; x 2, length 15 mm. The band above the fasciole as in Clavatula and Pseudomelatoma distinguishes the subgenus Crassispira from the other groups of Clavus page 581 Clavus (Crassispira) sp. indet., perhaps new, specimen No. 231 S. D. S. N. H., from the middle Pliocene of locality 2176, Holser Canyon, Los Angeles Co.; length 20 mm page 582 Clathurclla conradiana Gabb, specimen No. 236 S. D. S. N. H., from the Santa Barbara zone, upper Pliocene of locality 218, Sulphur Canyon east of South Mt., Ventura Co.; x 5, length 10 mm page 606 Moniliopsis graciosana (Arnold), specimen No. 635 in the collection at Stanford I'niversity, from the Pliocene 4 mi. west of Santa Barbara (if the label is to be trusted) ; length 19 mm. This specimen is apparently the young of the gerontic form shown in fig. 13 page 569 Moniliopsis graeiosa7ia (Arnold), specimen No. 636 in the collection at Stanford ITniversity, from the same locality as the specimen shown in fig. 12; length 28 mm page 569 Claims (Clathrodrillia) coalingensis (Arnold), specimen No. 232 S. D. S. N. H., from locality 207, lower Pliocene of Elsmere Canyon, Los Angeles Co. Fig. 14o, apertural view; fig. 146, side view showing roughly the notch; length 31 mm page 580 Clavus (Clathrodrillia) eoalingensis (.Arnold), specimen No. 233 S. D. S. N. H., from locality 204, lower Pliocene of Elsmere Canyon, length 25 mm page 580 Clavus (Cymalosyrinx) pallidus (Sowerby), siaecimen No. 234 S. D. S. N. H., from locality 2176, middle Pliocene of Holser Canyon, Los Angeles Co.; length 21 mm. Fig. 16a shows rather poorly the strong callus at the top of the inner lip page 576 Clavus (Cymalosyrinx) pallidus (Sowerby), specimen No. 235 S. D. S. N. H., found with the specimen shown in figs. 16, length 23 mm page 576 Pseudomelatoma penicillata (Carpenter), Recent specimen from Scammon's Lagoon, Lower California, labeled 429-3A in the collection at Stanford University; length 29 mm. This specimen is slenderer than the typical form, and shows a tendency to vary toward the variety semiinflata and P. lorosa page 560 (CoJitinued on page 940) Fig. 10. Fig. 11. Fig. 12. Fig. 13. Figs. 14. Fig. 15. Figs. 16. Fig. 17. Fig. IS. Volume I ] PlIOCENE AND PLEISTOCENE MoLLTJSCA OF CALIFORNIA PlATE 26 940 San Diego Society of Natural History [Memoirs EXPLAXATIOX OF PLATE 2e--(Continued) Fig. 19. Pseudoimhilimia penicillala (Carpenter) variety scmUnflatn, new variety, type, specimen No. 237, from the upper Pleistocene, Palos Verdes, of Santa Monica; length 34 mm page 561 Fig. 20. Pseudomelaloma torosa (Carpenter), Recent specimen from Monterey, labeled 42S-3A in the collection at Stanford University; length 31 mm page .5(52 Fig. 21. Moniliopsis incisa (Carpenter), typical variety, specimen No. 238 S. D. S. N. H., from locality 233, northwest corner of El Conejo Land Grant, Ventura Co.; length 30 mm jiage 56.5 Fig. 22. Spirotropis I Antiplanes) perversa (Gabb), specimen No. 239 S. D. S. N. H., from the lower San Pedro of San Pedro; length 33 mm. This is a dextral specimen of a species wliich has a strong tendency to be sinistral page 553 Figs. 23. Spirotropis [Antiplanes) perversa (Gabb), specimen No. 240 S. D. S. N. H., from the same locality as the specimen shown in fig. 22; length 29 mm. This is a sinistral specimen, a form more common in this species than the dextral. Fig. 23a is the same photograph as that shown in 236 reversed to show that the differences in the dextral and sinistral forms are all attributable to the accident of the way the shell began to coil l>age 553 Fig. 24. Spirotropis (Antiplanes) perversa (Gabb), ? variety pedroana (Arnold), specimen No. 241 S. D. S. N. H., from the same locality as the specimens shown in figs. 22 and 23; length 25 mm. This is a sinistral specimen badly weathered in such a w-ay as to produce a chan- neled suture like that shown in fig. 32. The trace of the posterior notch is also eroded out, producing a spiral line page 556 Fig. 25. Spirotropis (Antiplanes) perversa (Gabb) variety fernandoensis (English), specimen No. 242 S. D. S. N. H., from locality 207, lower Pliocene of Elsmere Canyon; length 30 mm. . . page 557 Fig. 26. Spirotropis (Antiplanes) cf. bulinioides (Dall), sjiocimen No. 243 S. D. S. N. H., from locality 207, found w'ith the specimen shown in fig. 25, length of incomplete specimen 30 mm .... page 557 Fig. 27. Borsonia bartschi (Arnold), specimen No. 637 in the collection at Stanford University, from the Pleistocene at San Pedro; length 25 mm. This specimen is an unusually elongate variation page 545 Fig. 28. Borsonia bartsehi (Arnold), specimen No. 638 in the collection at Stanford University, found with the specimen shown in fig. 27, length 17 mm. This specimen is more typical in shape. The cohunellar plication is very faint, but is unquestionably present page 545 Fig. 29. Spirotropis (Typhlomaiigelia) cf. renaudi (Arnold), specimen No. 244 S. D. S. N. H., from locality 218, Santa Barbara zone, upper Pliocene of Sulphur Canyon, east of South Mt., Ventura Co.; length 18 mm. This specimen, being badly weathered, appears to have lost most of the sculpture characteristic of this species page 549 Fig. 30. Moniliopsis graciosana (Arnold) variety mercedensis (Martin), specimen No. 245 S. D. S. N. H., from locality 233, found with the specimen shown in fig. 21, lower Pleistocene; length 26 mm. The Moniliopsis form of the notch is well shown, but the sculpture of the spire is hidden by encrusting bryozoa page 569 Fig. 31. Anacliis (Chaiiretia) lineolala. (Gray in Reeve), Recent specimen from San HQppolite Point, Lower California, labeled 356A in the collection at Stanford University; x 5, length 4.5 mm page 686 Fig. 32. Spirotropis (Antiplanes) perversa (Gabb) variety pe ronna (Arnold), specimen No. 246 S. D. S. N. H., found W'ith the specimens shown in figs. 22, 23, and 24; length 19 mm l>age 556 Fig. 33. Moniliopsis incisa (Carpenter) variety quinqmcineta, new variety, tyjie, specimen No. 247 S. D. S. N. H., from locality 207, lower Pliocene of Elsmere Canyon, Los Angeles Co.; length 20 mm page 568 Fig. 34. Anachis (Chauvetia) lineolata (Gray in Reeve), Recent specimen, from the same lot as the sjiecimcn shown in fig. 31 ; x 5, length 4.5 mm page 686 Fig. 35. Mitrclla carinnta (Hinds), typical variety, specimen No. 248 S. D. S. N. H., from locality 78, low, upjier Pleistocene terrace ]4 mi. south of Seacliff Station on the S. P. R. R. about S mi. northwest of Ventura; x 2, length 6.5 mm. The carination, though strong, affects only the last three-quarters of the body whorl page 692 Fig. 36. Heinipleuroloma archimedis (Bellardi), tj-pe of ihe genus H enii pleurotomn Cossmann 1889, repro- duction of Bellardi's original figure of the type specimen from the middle Miocene of Italy; length 38 mm page 570 Fig. 37. Taranis strongi (.Arnold), specimen No. 639 in the collection at Stanford L'niversity, from the Pleistocene of San Pedro; x 2, length 12 mm page 572 (Continued on page 941) Fig. 39. Fig. 40, Fig. 41. Fig. 42. Fig. 4.3. Fig. 44, Volume I ] PlIOCENE AND PLEISTOCENE MOLLUSCA OF CALIFORNIA 941 EXPLANATION OF PLATE 26— (Continued) Fig. 38. Sirombina renirm (Sowerby), sijecimen No. 249 S. D. S. N. H., from old beach north of Turtle Cove, Albemarle Island, Galapagos Group; x 2, length 13 mm. This specimen is like the one shown in fig. 41, except that the body whorl is broken off, giving it a very slender appearance page 699 Amj>hissa columbiana Dall, specimen No. 250 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co.; length 18.5 ram page 701 Xassarius (Tritia) mendicus (Gould) variety cooperi (Forbes), specimen No. 251 S. D. S. N. H., from locality 74, upper Pleistocene terrace southwest of Goleta, Santa Barbara Co.; length 19 mm page 674 Strombina recurva (Sowerby), specimen No. 252, from old beach north of Turtle Cove, Albe- marle Island, Galapagos Group; length 26 mm. This specimen is a good illustration of the genus Strombina page 699 Pyrene discors (Gmelin), Recent specimen from the Philippine Islands, No. 640 in the collection at Stanford University; length 17 mm page 680 Nassarius (Xassarius) legula (Reeve), Recent specimen from San Diego labeled S37A in the collection at Stanford University, natural size page 671 MilreUa carinata (Hinds) variety gaiisapata (Gould), specimen No. 2.53 S. D. S. N. H., found with the specimen shown in fig. 35, upper Pleistocene; x 2, length 8 mm. This is really but a variant of carinata, s. s page 693 Fig. 45. Mitrclla tuberosa (Carpenter), specimen No. 254 S. D. S. N. H., from locality 218, upper Pliocene of Sulphur Canyon, east of South Mt., Ventura Co.; length 7 mm. This speci- men is not particularly characteristic of the species, the spire being lower than usual and the body whorl less angulated at the base. It illustrates the variation of the species. A more typical specimen was found with it page 697 Fig. 46. Mitrella grandior, new species, type, specimen No. 6 S. D. S. N. H., from locality 221, middle Pliocene of Canada de Aliso, Ventura Co. ; length 22 mm. It is interesting to note that a very similar species, if indeed this is not the same, occurs in practically the same horizon in the English Pliocene page 696 Fig 47. Anachis (Anachis) (askoini Carpenter, Recent specimen from Point Abreojos, Lower Cali- fornia, labeled No. 887A in the collection at Stanford University; x 5, length 6 ram. . . . page 685 Figs. 48. A'^assarius {Uzila) amoldi (Anderson) variety whitneyi (Trask), speciraen No. 7 S. D. S. N. H., from the raiddle Etchegoin at a depth of 2680 feet in the Federal Exploration Company's well Kinsella No. 1 near Tipton, Tulare Co.; x 2, length 15 mm. This specimen was somewhat flattened by the consolidation of the bed in which it occurred page 679 Fig. 49. Nassarim (Tritia) californianus (Conrad), specimen No. 255 S. D. S. N. H., from locality 204, lower Pliocene of Elsmere Canyon, Los Angeles Co.; length (incomplete) 17 mm. This species does not have the varix on the outer lip. It is the tj'pe of Conrad's Schizopyga . . page 672 Fig. 50. Nassarius (Tritia) mendicus (Gould) variety cooperi (Forbes), specimen No. 256 S. D. S. N. H., from the same locality as the specimen shown in fig. 40; length 17 mm. It will be noticed that this specimen is a relatively shorter variant page 674 Fig. 51. NassaritLS (Tritia) perpinguis (Hinds), tall form, specimen No. 257 S. D. S. N. H., from the same locality as the specimens shown in figs. 40 and 50; length 17 rara page 673 Fig. .52. Nassarius (Tritia) perpinguis (Hinds), tall forra, specimen No. 258 S. D. S. N. H., from locality 2176, middle Pliocene of Holser Canj'on, north of the Santa Clara Valley, Los Angeles Co. ; length 17.5 ram page 673 Fig. 53. Amphissa versicolor Dall, specimen No. 259 S. D. S. N. H., from the lower Pleistocene o- Stanford University locality 602, west bank of road-cut 1500 feet north of crossing of Rincon Creek by California State Highway, southeastern corner of Santa Barbara Co.; X 2, length 12 mm page 702 Fig. 54. Xassarius (Tritia) mendicus (Gould), typical variety, short form, specimen No. 260 S. D. S. N. H., from locality 74, same locality as that at which the specimens shown in figs. 40, 50, and 51 were found; x 2, length 10 mm. This specimen is immature page 674 Fig. 55. Nassarius (Tritia) fossatus (Gould), young specimen, No. 261 S. D. S. N. H., from locality 74, low, ujjper Pleistocene terrace southwest of Goleta, Santa Barbara Co. ; length 16 mm . . page 675 Fig. 56. Xassarius (Tritia) fossatus (Gould), adult specimen. No. 262 S. D. S. N. H., from the same locality as the specimen shown in fig. 55; length 34 mm page 675 942 Pan Diego Society of Natural History [Memoirs EXPLANATION OF PLATE 27 Fig. 1. CanccUai ill IrUmiiittfi Gabb \-M-\ety fernandonisis Arnold, specimen No. 263 S. D. S. N. H., from Ideality 216, ba.sal Pliocene east of Fernando Pass, Los Angeles Co.; length 28 mm. Englisli figures a similar form from the same horizon in Elsmere Canyon. Arnold's type lackeera iBaird), specimen No. 291 S. D. S. N. H.. from locality 74, U])per Pleistocene terrace .southwest of Goleta, Santa Barbara Co.; length 29 mm paiie 7 1 1 Fig. 5. Tritonnlin lurida (Middendorff) variety iiniiida (Carpenter), specimen No. 292 S. D. S. N. H., from locality 74, found with the specimen shown in fig. 4; x 2, length 11 mm page 712 Fiii. 6. AcaiUhina spirata (Blainville), angulate variety, specimen No. 293 S. D. S. N. H., from the San Pedro Pleistocene; length 36 mm page 720 Fig. 7. Acaidhitia spirala (Blainville), angulate variety, specimen No. 294 S. D. S. N. H., from locality 244, Las Posas zone, lower Pleistocene in Sexton Canyon, Ventura Co.; length 28 nun . . |iage 720 Fig. 8. Acanthina spirala (Blainville), round-shouldered variety. Recent specimen from Bolinas Bay, middle California, labeled 709A in the collection at Stanford Universitj-; length 32 mm. . page 720 Fig. 9. Tmplinn (Bonotrnphon) orpheus (Gould), specimen No. 29.5 S. D. S. N. H., from locality 218, Santa Barbara zone of Sulphur Canyon east of South Mt., Ventura Co.; length 2.j mm . . . jiage 722 Fig. 10. Tritotialiu jiouhoni (Nuttall in Carpenter), young specimen. No. 296 S. D. S. N. H., from the San Pedro Pleistocene; length 2.5 mm page 712 Fig. 11. Tritanalia foveolala (Hinds), specimen No. 297 S. D. S. N. H., from locality 243, Las Posas zone, lower Pleistocene in Adams Canyon, Ventura Co.; length 32 mm page 709 Fig. 12. Chirnrcus (Muritha.is) wilkesanus (Anderson), specimen No. 298 S. D. S. N. H., from the ujiper (possibly middle) Miocene o ' the Superior Oil Company's well Ansolabehere No. 1, northwest of Bakersfield; length .55 mm page 730 Fig. 13. Tliais (Nucella) elsmercnsis, new species, type, specimen No. 299 S. D. S. N. H., from locality 216, lower Pliocene east of Fernando Pass, Los Angeles Co.; length 32 mm page 719 Fig 14. 77/((i.s iXucclla) lamello,m (Gmelin), Recent specimen from Coos Bay, Oregon, labeled 738-12A in the collection at Stanford University; length 43 mm. This specimen is one of the numerous variations of this extremely variable species. Compare fig. 26 page 716 Fig. 1.5. Thais (Nucdla) lima (Martyn), reproduction e — 000. Synonyms or names used incorrectly or in combinations not adopted in the present memoir are referred to in italics — 000. Illustrations are indicated by plate and figure. Footnotes are referred to by the letter "n." — OOOn. If the "n." is separated from the page number by a comma — 000, n. — ■, it signifies that the name or subject will be found somewhere else on the page, as well as in the footnote. Specific and varietal names are not listed under the genera to which they have been assigned but will be found in their ovn\ alphabetical order. Under each species or variety are arranged the generic and subgeneric names and combinations to which that species or variety has been assigned, including both the names that have l)een adopted in this memoir and those that have been cited from other works. No attempt has been made to include all the combinations, but every generic and suljgeneric name with which a specific or varietal name has been coupled in the text or synonymy should l)e represented in at least one of the combinations listed. Species or varieties are cited as synonyms in connection with all combinations except those actually adopted in this memoir. Hence, finding a name cited m the index as a synonym may mean that the species or variety is still valid and has merely been assigned to some other generic combination. With genera that have been divided into sub- genera, the genus name listed alone m the index under a specific or varietal name stands for the typical subgenus. In such cases, a species or variety belonging to some other subgenus will appear, when hsted after the genus name alone, as a synonym. On the other hand, with genera that have not been divided into subgenera in the text of this memoir, the accepted usage will be cited only mider the genus name alone; and when sectional names appear in generic combinations as if they were subgenera, a species or variety will be cited after them as a synonym. However, in every case the accepted usage will be listed close l)y. In many cases species or varieties have been mentioned in the text colloquially under old, discarded generic combinations or appear only under such com- binations in the s>Tionymy. This is especially true of sjaionyms. In such cases the species or variety s cited under the old usage or usages as a synonym, and under the accepted combination the page is referred to in parentheses — (000), {000) — , even though the accepted combination may not be found in the place indicated. In some cases the accepted combination may be found only in the index. Occasionally, subjects and systematic names or combinations implied but not directly expressed are cited with the page number in parentheses. The appearance of a name or subject more than once on a page is usually noted only when the occurrences are so far apart that one or more of them might be overlooked by someone in haste. A few abbreviations used in the text may require explanation: C. A. S. = California Academy of Sciences; San Francisco, California. L. S. J. U. = Leland Stanford Junior University; Stanford University, California. S. D. S. N. H. = San Diego Society of Natural History; Balboa Park, San Diego, California. U. C. = University of California; Berkeley, California. U. S. G. S. = United States Geological Survey; Washington, D. C. U. S. N. M.= United States National Museum; Washington, D. C. 960 San Diego Society of Natural History [ Memoirs abarbarea, Anliplanes, 55S. Spirotropis (Borsonella) , 552. Abbott, C. G., 9. abhreviata, Turns, 505. abdera, Clamis (Brachyioma ?), (583). Elspocyma, 5S3. abietis, Pecten (Aeqidpecten), 217, (S19), 220. Peclen (Plagiocieninm), 219. abrvpta, ? MaUelia, 132. Mya, J,S4, 4^5. Neilo, 132. Nucula, 132. Panope, J,2Jf, 425. Panope (Marganlaria), 424, (425). Panopea, J,24. Petricola, (355). Pholadomya, 424, 425. Saxicava, 355. Turritella, 775. abscissa, Maclra (Pseudocardium), (400), (403), (40^, n.). Schizodesma, 400, 403, 404, n. Spisida, 403. Abutting suture, illustrated, 796. Acanlhma, 719-720. Acanihinucalla, 720. Acanthinucella, 720. Acanthiza, 719. Acanthocardia, 303. acanthopterus, "Murex," 725n. Acar, 144, 144. Acardo, 313, 313. Acharax, 109. Achen interstadial, 68, 74, 75 (table). Acheulian culture, 68, 69 (table). acicula, Turritella, 776. Turritelopsis, 775, (776), 776. AcOa, 112-117; s. s., 112-115, 117. sp., 115, text. fig. 4. Acmxa, 462, 809-813, 954. Acmsids; 809-813. acolasta, Maconia, 371, pi. 14, fig. 7, pi. 20, figs. 4a, 4/), 10. AcHlla, 769n., 860. acroslephanurn, Epitonium (Crisposcala) , 858. EpiUmium (Nitidiscala), 858. Epitonium (Nitidoscala), S5S. acrostephanus, Nitidoscala, 868. Acrosterigma, 307. Actscon, 442 (twice), 443. Actseonidea, 443. Acteocina, 445, 446-449. Acleodnids, 444, 445. Acteon, 442-444, 446, 446. Acleonidse, 442-444, 444. Acteonina, 442. aclis, Astarte, 269. aculea, Cytharella, 601. Mangelia (Agathotoma), 587, (601). aculeata, Acanthocardia, (303). Crepidula, 791. Patella, 791. aculealum, Cardium, 303. acideiformis, Perrona, 611. acitminata, Cancellaria, 612, 613. Scalaria, 769n., 860. acuminatum, Agasoma (Bruclarkia), 491. Epitonium (Acrilla), (769n.), (860). Acus, 468, 469. acuta, Diala, 784. Leda (Lembuhis), 123. Maclra (Ahdinia), 4OI, 402. Nuada, 123. Nuculana, 123-124, 124. acutigemmata, Pleurotoma, 573. acutigemmatus. Teres, (573). aciitilineata, Cyclas, 287. Lueina (Myrtea), 137, 285, 286, 286-287, 288, pi. 14, figs. 22(7, 22f). Phacoides (Lucinoma), 287. acutilineatus, Phacoides, 287. acutilirata, Alvania, 768. Rissoa, 768. acutirostra, Hemipleurotoma, (570). Pleurotoma, 570. Adaaia, 313. adamsi. Bulla, 456. Bullaria, 456. Bullus, (456). adamsianus, Mytilus, 245. adamsii. Bulla, 466. Bullaria, 456. Bullus, (456). adana, Clathurella, (606). Glyphostoma, 606. adansonii, "Cerithium," 756. adelinie, Anachis ( — ), 688. adleri, Turbonilla (Pyrgolampros) , 869. Admele, 514, 622-623. Adrana, 119. adrastia, Cryplogemma, 548. Spirotropis, 548. adria, Clathurella, (606). Glyphostoma, 606. adscensionis, Pecten, 155, 157, 158. Adula, 252-253. adunca, Crepidida, 791. adustum, "Cerithium," 766. adversa, Triforis, 766. Triphora, (766), (766). icgialea, Mangelia (Agathotoma), (601). Philbertia, 601. segina, Clavus (Cymaiosyrinx), (576), 577. Elarocyma, 576. segrota, Daphnella (Anlimitra), (596). Pleurotoma, 596. seolia, Claims (Cymaiosyrinx), (578). Elaocyma, 57S. xpynota, Turbonilla (Chemnitzia) , 866. Aequipecten, 157, 170, 198-220, 230, 232, 888, 896; s. s., 198-202, 202, 206. sequiscuipta, Alvania, 768. Odostomia (Evalea), 874- Odostomia {Meneslho), 874. Odostomia (Oscilla), 874. Rissoa, 768. Volume I ] Pliocene and Pleistocene Mollusca of California 961 asquisulcalus, Pecten (Aequipeclen), 217, SIS, 219, 220 (twice). Pecten (Chlamys), 218. Pecten (Plagioctenium) , SIS. serope, Clavus (Cymatosyrinx) , 577. Elxocyma, 577n. Aesopus, 589, 5.91, 686, 703-704. asthiops, Buccinum, 6Jf9. Maa-on, 649 (twice), 649-650, 650, 944. sethra, Mangelia (Agathotoma), (601). Philbertia, 601. affinis, Cardita (Carditamera) , 27S. Clathurella, 606. Glans, 277 (twice), 278. Macoma, 368. Myurella, 466. Philbertia, 606n. Ranella, 734. Terebra (Strioterebrum) , 466. Aforia, 481 (diagram), 483, 487, 504, 507, 508, 509, 547. afra, Gadinia, 462. africana, Dosinia, 350. Aftonian interglacial, 71, 75 (table). agamedea, Antiplanes, 54S. Spirotropis, 548, 553. Agasoma, 60, 490, 491, 743, 743, 744, 744, 745, 745, 746, 749, 948. Agathotoma, 481 (diagram), 586 (twice), 587, 588, 589 (twice), 590, 592, 600 (twice), 600-601, 601, 610. Agina, 419, 427. Akerids; 455, 458-460. Akteophila, 461. Alaba, 76S, 784. Alabina, 758-759. alamadensis. Pinna (Atrina), 146. alamedensis. Pinna (Atrina), I46. ala-papilioni.'i, Paphia, 324, 325, text fig. 5a, 328. Alaska, fossils noted, etc., 7, 57. alaskana, Cardita, (273). Dosinia (?), 354. Mactra (Spisula), 395. Spisula (Hemimactra), 395, 396. Venericardia (Cyclocardia), 273. alaskensis, Astarte, 268-269, pi. 13, figs. 3a, 3b. Bela, 526. Lora, 526-627, .527 (twice), 528 (twice), 529. Mactra (Spisula), (395). Mangelia, .526. Pecten (Propeamusium) , 234. Pecten (Propeamussium), 234, 238. Pecten (Pseudamusium f), 234, 238. Sjrisula, 395. alata, Mactra, 402n. Mactrella, (402n.). Sanguinotaria, 384. alba, Cryptobranchia, 809. Cryptoctenidia, 809. Cylichna, (452), 453-454, 455. Cylichnella (Bulinella), 463. Cylindrella, 452. Lepeta, 809. Lepela (Cryptoctenidia), 809. Retusa, (44^). alba — continued. Valuta, 445, 461n. Volmria, 453. albaria, Mactra (Spisula), 21, 395-396, 397, 400, 403, pi. 23, figs. 3a, 3b. Spisula (Hemimactra), 395, 396. Tellina, 370. allxscens. Purpura, 705. albicans, Tellina, 362. albicostata, Drillia, 578n. Pleurotmna, 578n. Terebra (Strioterebrum) , 467. albicostatus, Clavus (Cymatosyrinx) , 578. albida, Pleurotoma, 504n. Turris (Polyslira), (504n.). albidus, Pecten, 167, 168. albocincta, Myurella, 469. Terebra (Strioterebrum), 467, 469-470, 470, 933, 955. albofasdata. Purpura, 705. albonodosa, Anachis ( ), 688. albrechti, Bela, 541 (twice). Lora, .533, 541 (twice). albus, Melampus (Leuconia), (461n.). Polinices, 799. alcatrazensis, Mactra (Spisula), (398). Spisula, 398. alcima, Cerithiopsis, 765. Alcira, 689, 692. alcmene, Clathrodrillia 1 (Kylix), 577n. Clavus (Cymatosyrinx) , (577n.). alcyone, Clathrodrillia ? (Kylix), 577n. Clavus (Cymatosyrinx) , 577. alderi, Turbonilla (Pyrgolampros) , 869. aldrovandi, Panope, 423. Alectrion, 670, 671, 672, 672, 673, 674, 675, 676, 677. Aletes, 777. aletes, Pecten, 222. Pecten (Janira), 95, 221, 222, 222. aleutica, Bela, 527. Cardita, (275). Cryptonatica, 798. Glycymeris, (275n.). Lora, 527, 527. Mangelia, 527. Mangilia, 527. Natica (Cryptonatica), 798. Natica (Tectonalica), (798), 799. aleuticum, Cardium, 135n., 276. aleuticus, Pectunculus, 275n. Taras, 294, 908. Alia, 683, 689, 690, 691, 692, 693, 697. Aligena, 300. Alipurpura, 706. alitakensis, Lora, 526-626, 529 (twice). Alluvium, 39, 45, 49, 61 (table), 63, 64, 65, 72, 73; for alluvial terraces, see terraces, younger fanglom- erate, older fanglomerate. almo, Turbonilla (Pyrgiscus), 870. Aloidis, 420, n., 420. alope, Placunanomia, 241. Pododesmus, (241). Alpine revolution, 23n., 66. Alps, 67, 68, 69 (table), 71, 74, 76n. 962 San Diego Society of Natural History I Memoirs aha, Anatina, 255. Apolymetis, (363). Littwina, 781. Lutricola, 364- Metis, 364 (twice). Neveriia, SOI. Paphia (Callilhaca), 327. Periploma, (255). PoUnices (Neverita), SOI. Polynices (Neveriia), 802. Siliqua, 38S, 388-389, 924, pi. 21, fig. 1. Telli7ia, 363, 363, 364, 364. Venerupis (Callilhaca), (327), 328. alternidenlala, Tellina, 363. aUhorpensis, Lora, 539. allhorpi, Lora (5 IS). Mangilia, 51S. allipleclus, Peclen, 166. aUiplicatus, Peclen, 166, 167. Peclen (Chlamys), 166. aUispira, Cancellaria, 617, 618, 620, pi. 27, fig. 7. Cancellaria (Progabbia), 618. Neptunea, 655. altii^, PoUnices (Neveriia), (SOI), 802, n. Solen, 388. Alvania, 767-768. Aniallhea, 7SS, 7S8. amara, Ostrea, 150, 152, 152. Turbonilla (Pyrgolampros), 869. amalhea, Clavus (Crassispira) , 682. fimatula, Cytliarella, 587. Mangelia, 587, 588. Amaiira, 807n., 875, 876-877. Amauropsis, 807. amava, Odostomia (Imra), 873. Amblychilepas, 84Sn. ambusla, Turbonilla (Mormula), 871, 872. ambusliis, Fiisinus, (641). Fiisus, 641. "Fusus," 641. americana, Bela, 537. ColumbeUina, 6S0ii. Lora, 537. Siliqua, 387. Americardia, 312. Amesoda, 298. amethysta, Gari, 382. amethyshis, Solen, 382. Amianlis, 222, 344, 346, 348-350. amiala, Lora, 521. arnica, Clavalula, 559. amiculus, Peclen (Pallium), 170. Amphidesma, 284n., 375, 376, 377. amphidesmoides, Loripes, (284n.). hucina, 284n. Amphineura, 878. Amphissa, 482, 513, 688, 700-702, 702 (twice). amphitrile, Antiplanes, 558. Spirotrojns (Antiplanes), 553, 558. ampla, Panope (Panomya), 426-427, pi. 21, figs. lOo, 10b. ampliata, Venerupis (Prololhaca) , (329). Venus, 329. amplicoslatus, Peclen (Aequipecten) , 217. ampulla. Bulla, 455, 4-56. Ampidlina, S07. ampullus, Bullwi, (4.55), (456), 457. Amstelien, 69 (table). Amusium, 13, 95, 156, 157, 192, 194, 196, 199, 200, 229, 230-232, 232. Amu&num, 230, 233. Amycla, 692, 693, 694, 697, 703. amycus, Antiplanes, 549. Leucosyrinx (Aforia), 508. Spirolropis (Typhlonwngelia), (549). amyela, Mangelia (Bela), (591). Philbcrlia (? Nannodiella), 591. amygdala, Yoldia, 131. Anachis, 482, 600, 684-689, 691, ii., 701; s. s., 684-686. Anadara, 137, 137, 138, 1.39, I4I. Anadema, 821. Anatina, 255, «., 406-409, 4O6, 414n.; s. s.,406, 407, 409. anatina, Anatina, (406). Anodonta, 244. Maclra, 4O6. analinus, Mylilus, 244- anazora, Olivella, 627. anceps, Pleurotoma, 573. Teres, 540, (573), 573. Ancistrolejns, 651, 657, 660, 660, n. Ancistrosyrinx, 481 (diagram), 483, 504, 505, 506. Ancylus, 463, 464. andersoni, Cancellaria, 619. Chrysodomus, 655. Nassarius (Uzila), 678. Natica (Neveriia), 802. Neptunea, 35, 656-656, 656, 658, 659, 944. Pecten, 202. Peclen (Aequipecten), 201, 202, 202-203, 206, 238n., 745, pi. 4, figs. 4, 5. Pecten (Plagioclenium), 202. Pecten (Pseudamu^ium), 238n. Pecten (Pseudamussium), (238n.). PoUnices (Neverita), 802, 803 (three times). Andes, 76n. andromeda, Clalhrodrillia, 486n. Clavalula (Trachylochetus), 486. anellum, Pelaloconchus, 778. Vermelun, 778. Vermiculmn, 778. angelana, BorsoneUa, 550, 551. Cancellaria, 618. Spirolropis (BorsoneUa), (550), (551). angelena, Olivella, 625. angelensis, Cantharus, (647). Priene, 738. Ranella (Priene), 40, 738. Solenosleira, 647. angelica, Ostrea, 150. angelina, Olivella, 625. Anglo-Belgian basin, 66, 71. angularis, Strombina, 700. Yoldia, 127. Volume I ] Pliocene and Pleistocene Mollusca of California 963 angulnia, Cythara, (593). Lora, (515). Maclra (Mulinia), 401. Mangelia, (520), 593. Ma7igilia, 520, 593. Mulinea, 401. Olira, 633, 624 (twice). Pisania, 647. Tivela, (340n.). Anyiilalomilrella, 689, 693. angulaium, Tivela (Pachydesma) , 340n. angulatus, Cantharus, 647. Murex, 515. angulifera, Divaricella, (295). Lua'na, 295. angulosn, Bela, 521. Lorn, 518, (521), 522. angutosum, Buccinum, 668, (668-669), 669n. Angiilus, 357, 35S, 360, 361, 361, 362, 362. angu.^ta, Maclra, 392. Mangelia (Agalhotoma) , 600. angvstifrons, Diane, 345. Pilar, (345). anguslior, Acleocina, 448. Relusa (Acleoci)ia), 448. anneUse, Cyprxa, 752, 752. annosa, Surcula (Surculiles), 492. annosus, Surctdiles, (492), 493. anmdala, Lucina (Myrtea), 287. Phacoidesi (Liicinoma), 287. anrndalum, Calliostuma, 832, 835. atmrdalus, Pecten (Pseudamvssium) , (236). Phacoides (Ludnoma), 287. Plagiostoma, 236. Hpirnglyph us, 778. Trochus, 832. Zizyphinus, 832. Anodonla, 244. AnodorUia, 285, 292. anmnala, Isapis, 783. Iselica, (783). Opalia, 854. Pyrula, 646, 648. Solenosleira, 648. Anomalocardia, 137. Anomalodesmacea, 255-266. Anomalosipho, 662, 662-664, (664— as LaHsipho). anomalum, Epilonium (Opalia), 853, 854. arumialus, Cantharus, (646), 648, 729. Anomia, 240-241, 241, 241, 243, 44O. Anomiacca, 240-243. Anomiidse, 240-243. Antalis, 437. antecedens, Lucina (Myrtea), (288). Phacmdes, 288. antefilosa, Cerithiopsis, 765. anlegressa, Milra, (636n.). Uromilra, 636n. anleslriala, Turbonilla (Pyrgiscus), 870. ArUigoiut, 316-317, 317, 321, 349. anligonc, Antiplanes, 548. Cryplogemma, 548. Spirotropis, 548. anlillarum, Crassalella, 271. Crassatelliles, 271, 272, n., pi. 13, figs, la, 76. Anlimilra, .596 (twice). Anliplaiies, 481 (diagram), .543, .544, 547 (twice), 548, 549, 552. 652-558, 563, 568. antipoda, Lora, 594. Mangelia (Bela) ?, (594, twice). anliqua, Neptunea, 648, (652), (653), 653, 661, 662, 944, pi. 28, fig. 10. anliquata. Area, 137, 138. Cardila, 272. Chama, 272. Patella, 788. aidiquatus, Hipponix, 788. Taras, 293. ardiquum, Trilonium, 652. anliquus, Fusiis, 652, 944. Murex, 652, 6.53 (twice). anliselli, Nassa, 678. Nassari-us (Uzila), 408, 678, 679. Apalurris, 596. apertura, Diodora, (849). Patella, 849. aphela, Neptunea (Colus), 663, (663), 664. aphelus, Chrysodomus, 663 (twice). Colus (LaHsipho), 663. Aphera, 612. Aphrodite, 313, 313. apicinum, Lsevicardium, 305. Aplacophora, 878. apogrammatus, Contis, 475. Apollo, 733. Apollon, 733. Apolymelis, 363-364. Apophysis, see styloid. Aporrhais, 705. appressa, Drillia, 582. appressu^. Claims (Crassispira) , (582). approximata, Lucina (Myrtea), 289, pi. 14, figs. 8a, Sh. approximatus, Phacoides (Parvilucina) , 289 (twice). arabicula, Cyprsea, 753. arachnoidea, Oliva, (624). Porphyria, 624- aragonia, Tellina, 358. Aral Sea, 303n. Ara7iea, 704- arata, Cardila, 278. Glaus, (278). Tindaria, 132. aratus, Saxidomus, 341, 342. arbela, Clavus (Cyinatosyrinx), (578). Elseocyma, 578. Area, HI, 118, 119, n., 120, 127, 133, 137-144; s. s., 137-141, 142, 144. Arcacea, 133-144. arces, Pecten (Pseudamusium), 238. Pecten (Pseudamussium), (238). archimedis, Hemipleuroloma, (570), pi. 26, fig. 36. Pleurotoma, 570. Architectoma, 785. Archilectonica, 785-787. Architectonidda;, 785-787. 964 San Diego Society of Natural History [ Memoirs archon, Peclen (Janira ?), 184. Arcidx, 8, 13, 133-144. Arcinella, 277. arcirwlla, 1 Arcinella, (277). Chama, 377, 280. Echinochama, 280. Arcopagia, 364- Arcotia, 769. arclica, Astarle, 267, 267. Bda, 533. Cardita, J,27 . Crassina, 267. Glycimeris, 426. Hiaiella, 427. Leda, 127. Lara, 531, 532, 533-634, 536, pi. 32, figs. 44, 45. Mya, 4^~- Neptunea (Colus), 664. Nucida, 126, 127, 130, 131. Panopsea, 426. Pariope (Parwmya), 426. Porllaiidia , 127n. Saxicava. 427-428, 428, 429. Yoldia, (126), 127, 127, 12Sn., {ISO), 131, pi. 1, figs. 10, 11. arcticum, Cardium, 310. Lxvicardivm. (Cerastoderma), {310). arcticus, Cadulus, 439. Fusus, 664. Plicifusus, 664- Arcloscala, 856. arcuala, Petricola, 355. Arcuatomiirella, 689, 692. arcuatvs, Conns, 477. "Typhis," 725n. Arcularia, 670, 670, 671. arcularia, Arcularia, {670). Buccinum, 670. Nassarius, (670). arenaria, Mya, 53, 67, 70, 410, 411, 411-414, 414, 415, 416 (twice), 417, 419, 924; s. s., 411-412, 413. arenalum, Cardium, 306. Lseiricardium {Trachy cardium) , {306). arenosa, Lyonsia, 264. Oliva, 624. Pandorina, 264. aresta, Turhonilla {Strioturbonilla) , 868. argenlaria, Periplotna, 255. argeta, Leucosyrinx {Steiraxis) ?, (509). Phymorhynclnis, 509. Argina, 138. Argobuccmiim, 734, 735, n., 737, 737, 738, 739. argus, ColuinheUa, 696. Mitrdla, {696). Murex, 734. Ranella, section Argobuccinmn, (734). argyrosloma, Tegida, (825). argyrostomus, Trochus, 825. armillala, Terebra {Striolerebrum) , 467, 467-468. armillalum, Billium (Semibiltiimi) , 762. Semibitiium, 762. amheimi, Macoma, 367-368, 368. arnoldi, Anachis (Chauvetia), 688. Argobuccinutn, 738. Astralium, 820, 827. Billium {—), 763. Cancellaria, 621-622. Cantharus, 647. Chrysodomus, 647. Columbella {Anachis), 688. Dosinia, 352. Fusi7uis, 639, 639-640. Fusus, 639. Mantra {Spisida), 396. Melanella, 862. MelaneUa {Balds), 862. Nassa, 679. Nassarius {Uzita), 408, 678, 679, 941. Peclen {Lyropeclen) , 188. Polinices, 800. Ranella {Priene), 738. Tegula {—), 827, 831. Tegula {Chlorosloma), {820), {827). Turbonilla {Pyrgolampros) , 869. Arrhoges, 705. arsino'e. Claims {Crassispira), 581. arteaga, Mangelia {Bela), 594, 595-596. Mangilia, 595. Artemis, 351, 354. Asapkis, 363. Ascension Island, 157. ashiyatnsis, Nucula {Acila), 115. ashleyi, Cantharus, 647. Peclen {Lyropeclen), 40, 187. asmi, Acma?a, 812. Collisella, 812. Patella, 812. aspera, Daphnella, 597, 598. Diadora, 850. Diodora, 850. Fissurella, S50. Fissiiridea, 850. Glyphis, 850. Mangelia {Mitromorpha), 597 (twice), 598, 598-599, 599. Mitromorpha, 698. Ocinebra, 711. Trilonalia, 711, pi. 32, fig. 4. Turbonilla, 760. Vitularia, 711. Asperiscala, 856-857. aspersa, Bulla, 456. Bullaria, 456. Papyridea, 311. aspersum, Cardium, 311. asper.suSi Bullus, 456, 456. Pecten {Aequipecten), 206. asperum, Bittium {Lirobittium) , 759, 760-761, 930. asser, Turbonilla {Strioturbonilla), 867. assimilata, Cerilhiopsis, 764- Seila, 764, 764. assimilis, Bela, 516. Lora, {516), .520. Assiminea, 787. Assula, 541. Volume I ] Pliocene and Pleistocene Mollusca of California 965 Astartacea, 266-272. Astarte, 96, 266-269, S?0, 271,. Aslartids, 2G0-209, 269, 270, 272. astarloides, Liocyina, (336). Venus, 336. Asthenoloma, 481 (diagram), 568, 573. Astien, 69 (table), 70. astori, Macoma, 369, 369. Astoria beds, 59. asloriana, Nuculana, 121, 122, pi. 32, figs. 46, 47, 48. Yoldia, 955. YoUia (Porllandia), 122. Astrsea, 817-821. Asiralium, 817, SIS, S19, 820, S27. Astrodapsi.-i, 30. Astyris, 683, 689 (twice), 691, 692, 693, 694, 695, 697, 70S. athleta, Venus (Chione), 323. Atilia, 684, 685, 691, n. Atlantic, connection with the Pacific; southern, 93, 94, 95, 96; northern, 96-97; see also Caribbean. Atoma, 584- atramentaria, Anachis ( — ), 688. Airimilra, 635, 636. Airina, 145, 146-147, 147. allalia. Claims [Cymaiosyrinx) , {578). Elseocyma, 578. attenuaia, Bela, 589. Bulla, 457. Mangelia, (585), 585, (589), pi. 25, figs. 18, 19f;, 19t). Purpura, 717. Raphiloma, 585. Thais (Nucella), (717). atlenualum, Bittium (SemibiUium), 762. altenuatus, Bullus (457). Murex, 585. allonsa, Cylichna, 454, 464-466. Cylichnella (BullineUa), 454. attrita, Turbonilla (SlrioUirbonilla) , 867. atwoodi, Epitonium (Acrilla), 860. Ostrea, 21, 153, 163. Atys, 451. auburyi, Pecten, 226. Pecten (Janira), (226), 226, 227, 228. auguslinense, Calliostoma, 834. auguslinensis, Calliostoma, 834- aulaca, Leucosyrinx (Sleiraxis) , (509). Pleurotoma (Sleiraxis), 509. aurantia, Callista, 347. Chemnitzia, 869. Cytherea, 347. Dione, 347. Drillia, 562. Pseudomilatoma, 662-663. Turbonilla iLancea), 869. Turbonilla (Pyrgolampros), 869. auranliaca, Cytherea, 346, 347. Lacuna, 783. Macrocallista (Chionella), 347. Meretrix (Callista), 347. auranliacus. Pilar (Megapilaria), (346), 347, 347. auranlius, Pilar (Megapilaria), (347). aurea, Clathurella, 510, 604. aureotincta, Tegula (Chlorostoma), 830. Tegula (Omphalius), 8-30. aureotinctum, Chlorostoma, 830. aureotinclus, Omphalius, 830. aureo-tinctus, Trochus (Monodonia), 830. auricoma, Turbonilla (Pyrgiscus), 871. auriculifer, Claincnntha, 574. Claims, (574). Drillia, 574. Pleurotoma, 574- aiistralasix, "Monoplex," 734, n. australe, Buccinum, 813. Epitonium (Opalia), (853), 853. australis, Opalia, 853. Phasianella, (813), n. Rocheforlia, 301. Solemya, 109. Turricula, 487. Austrofusus, 642. Austrotrophon, 724, 725, 726, 727. avellana, Odostomia (Amaura), 876, cf. pi. 32, fig. 20. Avicula, 147, 148. Amculopecten, 235. Aviculopinna, 144. aiita, Forreria, 727, 728. avitum, Trophon, 727. Axinsa, 133, 134, 136, 287. B babylonia, Lora, 522, 522. Turris, (483), 503, 505. babylonica, Turris, 4S3, 503. babylonicus, Murex, 503. babylonius, Murex, 503. bacchia. Claims (Crassispira), 582. bacula, Homalopoma, 822. Leptonyx, 822. Leptothyra, 822. basri, Buccinmn, 669n. bxtica, Olivella, 626, 627, 627. bainbridgensis, Cochlodesma, 255n. ? Thracia (Cyathodonta) , (255n.). bairdi, Chrysodomus, 658. Neptunea (Sulcosipho) , (658). Baker, Fred, 9. bakeri, Fartulum, 780. Pecten (Janira), 224-226, 230, pi. 4, figs, la, 16. Pecten (Patino pecten), 224- Bakersfield, 52, 53, 63. Balanelta, 629. Balds, 861, 862. Baldwin Hills, 41, 42, 43, 71. balthica, Macoma, (67), 371-372, 372, 922, pi. 14, figs. 6a, &}, pi. 20, figs. 7a, 76. Tellina, 67, 371. Baltic interstadial, 68, 75 (table), 76. Bankia, 930. barbarense, Bittium (hirobittium) , 760. barbarensis, Alabina, 758. Axinxa, 134- Borsonella, 551. Bwsonia, 551. 966 San Diego Society of Natural History Memoirs barbarens-is — conlinued. Cardita, 44, 274. Caryatis, 346. Fusimis, 34, 35, 44, 638, (638), 639, 639-640, 640 (twice), 641, pi. 27, fig. 11. Fusus, 63S, 639. Glycymeris, 134, 134, 135, 135. Mnngeb'a (Bda), (594). Mayigelia (Mitromorpha), [598). Mangilia, 594- Mitromorpha, 598. Murex, 709. Muriddea, 709. Ocinebra, 709. Pilar, 346. Psephidia, 337, 337. S]nrotropis ( Borsonella) , 550, 551, 551, 552. Tritonalia, 709, 710. Venericardia (Cydocardia), 274- Barbarofusus, 638. harbala, Area (Barbatia), 143. Avinda, 14S. Plena (Pinctada), (US). Barbatia, 143, 143-144. harbalus, Hippiniix, 789. barkerianiis, Peden (Aequipedcn) , {202). Peden (Plagiodenium) , 202. Barleeia, 784, 784-785. Barlow Canyon and Barlow Ranch, 104. Barven, 431-432. Barnin, 431. Bartschdla, 872. barlschi, Bor.'iondla, 545. Borsonia, 543, 544, 545, 546-546, 546, 549, 563, pi. 26, figs. 27, 28. Daphnella, 542 (twice). Peden, 161, 168-169. Peden (Chlamys), 16S. Pleurotoma, 545. bartschii, Anachis, 688 (twice). Bas.sler, R. S., 9. basleroli, Pleurotoma, 573. Terebra (Striolerebrmn), 466. Teres (AsiheiMlomn), (573). Bath-house Beach, 36, 101. Bathytoma, 481 (diagram), 4S8, 495, 496n., 497, n., 498, 499, 502, 502-503, 504, 580. beali, Conus, 476 (twice). Peden, 222. Pectin. (J antra), {222). Bear River "Miocene," 55, 61 (table). Bear VaUey, 44. beckii, Defraiicia, 540. Lora, 540. behri, Amiantis, {349). Pitaria, 349. behringii, Neptunea, 651n. Tritmdum, 651n. Volutopsius, 651, (n.), (652n.). Beta, 479, 481 (diagram), 511, 512-541, 513, 575, 584, 585, 586 (twice), 588, 589-596, 597, 601, 665n., 9.55; s. «., 513, 589-592, 593, 595, 596. belcheri, Chorus, 726. Forreria, 707, (725, n.), 726, 726-727. Murex, 725, n., 726. "Typhis," 725n. Belgium, 66. bella, Janira, 225. Tornatellsea, 442n. BcUnrdia. 609. Bellardiella, 609. Bellaspira, 481 (diagram), 514, 565, 575, 584, 584, 586. bellaslriala, Asperiscala, 857. Scala, 857. Scalaria, 857. bellastriatum, Epitonium (Asperiscala), (856), 857. bellilameUatus, Peden (Aequipeden) , 204, 205, 206. Peden (Chlamys), 205. Peden (Leptopeden), 205. Bellucina, 290. bellus, Peden, 225. Peden (Janira), 21, 30, 34, 42, 202, 221, 223, 225-228, 229, 884, 886; s. s., 224, 225-226. benthima, Cryptogemma, (570). Gemmula, 570. Hemipleurotoma, (570). benlleyi, Barleeia, 784. Trophon {Boreotrophon) , 724. beringi, Anliplanes, 556. Boreotrophon, 721. Neptunea, 721. Pleurotoma, 556. Spirotropis (Anliplanes), (556), 556. Trophon (Boreotrophon), 721. Trophon (Neptunea), 721. Volutopsius, 652n. beringianus, Peden, 35, 163, 165-166, 167, pi. 11, fig. 2. Beringius, 651, 653, 653, 657. Berlin, 68. bero'e, Anliplanes, (558). Spirotropis (Anliplanes), 558. berryi, Melanella, 862. Melanella (Balds), 862. berlrandi, Mangelia (Agalhotoma) , (589), (600). Pleurotoma, 589, 600. beta, Mangelia (Beta), (594). Mangilia (Kurlziella) , 594- Tritonalia, 710. bezoar, Rapana, 646. hiangularis, Apolymelis, (364). Scrobicularia, 364. biangulala, Apolymelis, 363-364, 364, pi. 20, fig. 16. Astrsea (Pomaulax ?), 819. Scrobicularia, 364. biangulatum, Cardium, 312. Fragum, 312, 312. Bibliography, 98-101; works designating molluscan types, 84-85; works on Pliocene and Pleistocene mollusca of western North America, 98-99, 101; works on Recent mollusca of western North America, 98, 100-101. bicarinala, Astra:a (Pomaulax) ?, (819). Beta, 538, 539. Didonla, 427. Volume 1 1 Pliocene and Pleistocene Mollusca of California 967 hicnrinnta — con'inucd. Kennerlia, S61. Lorn, 538-540, 541 (twice). Nodiscaki, 85o. Pandora, 261. Pleurotoma, 538. Saxicava, {427). ' hicarinalum, CaUiosioma, 819. Epitonium (A'odincala), (855). hicolor, Amphissa, 702. Chicm-eus (Phyllonotus), {730). •'Drillia," 583. Murex, 730. "Murex," 730. Philbertia {609). Phtjllonoiiis, 730. Pleurotoma , 609. Raphitoma, (609). bicoronata , "Rouaidtia," 505. bicuneata, Pinna {Atrina), 146-147. bidentata, Bulla, 453n. Cylichnella, (453n.). Valuta, 461. bidentatus, Melampus {Leuconia ?), (461n.). bifasciata, Nassa, 673. Natica, 800. bifasciatus, Xassarius {Schizopyga) or Nassarius {Tri- tia), (673), 674. Polinires, 800. bifida, Nucida, 112. biformatus, Pecten {Lyropecten) , 184, 186. Ufrons, Pholas (Zirfiea), 433. Bifrontia, 7 Son. hifurcatvs, Mytilus, 247. Septifer. 247-248. 248. bilineata, Wnii.-i iChione), 322. bilinealus, Pecten {Aequi pecten), {199), 200. Pecten {Plagwctenium) , 199. bilirata, Kenriidia, 261. Kennerlyia, Wl. Pandora, 261. Sphse?iia, 41 9n. Sphenia, (419n.). bilocularis, Mytilus, 247. Septifer, (247). himaculata, Clypidella, S49. Fissitrellidsa, 849. Fissurellidea, 848, n., 849. Megatebennu.s, (S48, n.), 849. bimaculatus, Megatebennus, 849. bimarginata, Clavatula, 483, n,, 484, pi. 25, figs. 14((, 146. Pleurotoma, 483n. hinghami, Sphenia, 419. binominata, Corbula, 420 (twice), 421. hinominatus, Pecten {Pseudamussium), 238. biplicata. Ohm, 625. Oliva {Ciilliiiiioi}, i:2-'i. Olivella, 625-626, 627, pi. 24, fig. 15. Olivilla, 625. biradiata, Cytherea, 347. biradiatus. Pilar {Megapitaria), {347). bisecta, Conchocele, 281. Cyprina, 281. bisecta — continued. Thyasira, 281-282, 282, 906, cf. pi. 13, fig. 15. Venus, 281. bisecttis, Cryptodon, 281. bistorta, Eulima, 862. Melanella, {862). bistriatum, Pseudamusiutn, 238n. bistr'atus, Pecten {Pseudamussium), (238, n.). Bithynia, 68. Bittium, 7.58, 759-763, 766, 776. Blackwelder, E., 53. Blainvillia, 333. blancoen.sis, Acila, 117 (twice); see Nucula {Arila) Nucula {AHla), (117), 117. blanda, Cochlespira, (505). Cochlapiropsis, 505. Daphnella {Surculina), 509. Leucosyrinx {Surculina), (509). blandum, Cardium, 309. Lsmicardium {Cerastoderma), {309). Blepharipoda, 911. bodegensis, Tellina, 362, 373, pi. 20, fig. 13. Telli7ia (Angulus), 362. Tellina (Peronidia), 362. boetica, Olivella, 627. bogachielii, Buccinum, 669. Boletus, .564. bonellii, Pseudoloma, 494, 500. Surculites (Clinura), (494), (500). bonita, Haliolis, 847. boreale, Cardium, 310, 314. Epitonium { — ), 853. Epitonium {Opalia), {853). Lsencardium {Cerastoderma), {310). borealis, Astarle, 67, (266), 267, 268. Bela, 531. Cardita, {272), {273), 274. Chrysodomus, 657. Epitonium, {Opalia), 853. Fusus, 657. Lora, {531), {540). Lucina {Myrtea), (267), 287. Neptunea, 657. Opalia, 853. Pecten {Aequipeclen) , 217. Pleurotoma, 540. Scalaria, 8.53. Serripes, {314). Soleynya {Pelrasma), 109. Tridonta, 266, 267. Venericardia, 272, 273. Venus, 266, 267. Boreoscala, 856, 861. Boreotrophon, 710, 721-725, 725, 726. Bornia, 300, 301. Borsonella, 481 (diagram), 543, 544 (twice), 54S, 546, 547, 550, 550-552, 567. borsani, Mitrella, 697. Borsonia, 480, 481 (diagram), 483, 543-546, 546, 547, 549 (twice), 550, 550, 551, 563, 572, 610. bSsei, Pecten, 224. Pecten {Janira), {224). Turntella, 775. 968 San Diego Society of Natural History [ Memoirs bolts', Claims (Crassispira), (580), (581), 582 (twice), pi. 26, figs. 63, 6b. Plcuroimna, 580 (twice), 581. Botula, 252-253. hovini, Coluinbdla, 68$. Pyrene, (682). bowersi, Peclen (Lyropecten), 189. Peden (V eriipecten) , 188, 190. Boxstones, 66, 68, 69 (table). Boytonian, 69 (table). Brachidonles, 245, 246, 252. bradiis, Lora, 513, 523, 524. BrachUoma, 583. Brachydontes, 246, 252. Brachystoma, 583. Brachytoma, 481 (diagram), 583. branneri, Aslarte, 270. Crassinella, 270. Cylharella, U, 587. (Gouldia), cf. 270n. Kelletia (Searlesia), 646. Mangelia, (587). Marigilia (Cythara), 587. Peden, 162. breaensis, Aslrsa (Pomoid, 11, 14a, 146; see also Cryptomya californica zone. Cumingia, 378. californica — continued. Cyclostrenwlla, 844- Cyrena, 298. Delphinoidea, 844, 844. Donax, 379. Gari, 382, 383. , Glacis, 278. Hyalina, 629, 630, 631. Hydrobia, 787. LuHna (Myrlea), 285 (three times), 285-286, 286, 288, pi. 14, figs. 1.5a, 156, 21o, 216. Lyonsia, 263-264. Mactra, 392, 392-393, 392, (398). Mactra (Maclroloma), 392, 393n. Marginella (Hyalina), 630. Megathura, 848. Muricidea, 706. Mya, 417. Nepturiia (Anci.'itrolepis), (657). Ostrea, 149-150. Pelricola, (355). Phacoides, 285. Pholadidea (Parapholas), (435), 435. Pholas, 435. Placunanomia, 243, 243. Psammobia, 382. Purpura, 706. Ranella (Lampas), 731. Saxicava, 355. Siliqua, 387. Sphsmia, 416, 417. Slandella, 398. Strombiformis, 865. Syncera, (787). Transennella, 339. Trivia, 753. Truncatella, 787, 787. Venericardia, 273. Volvulella, 450. californicum, Bittium, 758. Bittium (Elachisla), 758. Cs-cum, 779. Calliostoma, (835). Homalopoma, (822). Sinum, 806. californicus, Ancistrolepis, 657. Capulus. 788, pi. 32, fig. 33. Conus. 472-473, pi, 24, fig. 21. Donax, 379-380, .380, 380. Gobrsnis, 382. Murex, 706. Phacoides (Epilucina), 285, 286. Pholas, 435. Turbo, 822. "Turbo," 822. Zizyphinus, 835. californiense, Cardium, 308, 309. Lxvicardium (Cerastoderma), (308), 309, pi. 19, figs. 13, 16. calif orniensis, Botula, 253. Haliotis, 847. Macoma, 373. Vemis (Chione), 321. 970 San Diego Society of Natural History [ Memoirs colli, Peclen (Aequipeclen), (302), 217, 219. Pecten {Plagioclenium) , 202, 218. Callianax, 625. callianira, Clathrodrillia, 580. Claims (Clathrodrillia), (580). callicera, Volvulella, 450. callidtm, Peclen (Aequipeclen), 208, 211, 211, 890, pi. 5, fig. 4. Pecten (Plagioctenium) , 211. calliope, Murex, 494- Pleurotoma, 494- Surculites [Clinnra), (494). Calliosloma, 819, 826, 831-837, 8.37 (twice), 837. Callista, 334, 343, 345, 347, 351, 395. Calliihaca, 326, 327-328, 328. CalKtropis, 838. callomarginata, Clypidella, 849 (twice), n. Lucapinella, (849), 849. Callopoma, 816-817. callosa, Amiantis, 344, (348), 348-349, 352, 408, pi. 17, figs. 7, 9, 11, 12, 13, 14. Callista, 348. Cylherea, 348 (twice). Bicme, 348. Dosinia, 348. Neverila, 802, 803. Venus (Chimie), 323, 348. callosus, Polinices (Neverita), 408, 802, n., 803, text. fig. 14. Calhidna, 285, 286. Galium, 430. calophylla, Circomphalus, 333. calyculata, Cardila, 277, n. Chama, 277n. Glaus, 277. calypso, Cryptogemma, 511n. Pleurotomoides ?, 511. Calyptogena, 278-279. Calyptrsea, 462, 791, 792, 70S, 794-796, 813, 954. Calyptrsndse, 793-796. camdenensis, Cyrtodaria, 429. camerina, Cytharella (Agathotonm) , 601. Mangelia (Agalhotoma) , (601). cameronis, Mactra (Spisula), (398). Spisula, 398. camnumi, Argobuccinum (F usitriton) , 739. Calliostoma, 834. Priscofusus, 491, 492. Ranella (Priene), 739. Turris, 491. catnpechensis, Anatina (Pacta), (407, twice). Mactra, 407. Raela, 407 (twice), 408. Camptonectes, 235. camuloensis, Area, 30, 34, 61 (table), 139, 140, 884, pi. 2, figs. 5a, 5h, 5c. camura, Malea, 741. canalicularis, Clavus, (574), 575 (twice). Stro7nbus, 574. canaliculata, Anatina (Raela), (407, twice), 408. Labiosa (Pacta), 408. Lutraria, 407 (twice). Maclra, 407. cannlirulala — continued. Purpura, 718. Thais (Nucella), 718, 719. canaliculatum, Calliostoma, 833, 833, pi. 32, fig. 23. canaliculatus, Buccinopsis, 666. Liomesus, 666. Trochus, 833. canalis. Area, I40 (twice). Cancellaria, 602, 602, 612-622, 622, 623, 714, 767; s. s., 612-614, 614. Cancellariidie, 8, 13, 612-623. cancellaris, Lucina (Bellucina), 290. Phacoides (BeUucina), 290. Cancellarius, 612. cancellata, Bela, 521, 525. Cythara (Cytharopsis), (603n.). Drillia, 565, 566. "Drillia," 565. Lora, (.521), (525), (529). Mangelia (Cytharopsis), 603n. Moniliopsis, (565), (566). Mya (Platyodon), 415, 415-416, pi. 24, figs. 3a, 36. Ranella (Priene), (736), 737, (737). Venus (Antigona), 316n. Venus (Chione), 316n., 317, 318 (twice). cancellatum, Cerilhium, 761. Bitlium (Semibittium), (761). Triton, 736, 737. Tritonium, 737. cancellatus, "Fusus," 529. Fusus, 529, 737. Mya (Platyodon), 4I6. Pecten (—), 232. Pecten (Propeamussium) , (232). Peclen (V ariamussium) , 232. Platyodon, 415. Triton, (736), 737. Triton (Priene), 737. cancellina, Ocinebra, 711. Tritonalia, 711. Urosalpinx, 711. cancellinus, Fusus, 711. Camilla, 636. candace, Clavus (Crassispira) , 582. Candelabrum, 506. Candida, Cancellaria, 613, 613, 614. Clathurella, 605. Clavatula, 605. Mangilia, 605. Pleurotoma, 605. candidissima, Anachis (Chauvetia), (686, three times). candidissimuiyi, Buccinum, 686. candidus, Pholas (Barnea), 431. canfieldi, Clathurella, 606, 607. Philbertia, 607. catirena, Natica (Nalicarius), (796), 797. Nerita, 796n. Cantharidus, 824. Cantharis, 646. Cantharus, 642, 644, 646-649, 729. Cantrainea, 821. Canyon stage in the Yosemite, 76n. (on 77). Volume 1 1 Pliocene and Pleistocene Mollusca of California 971 capax, Lutraria, 404, 405. Modiola, 249. Modiolus, 249. Schizothsrus, 404, 405. Volsella, 249, 249, 251. Cape Blanco, Ore., 61 (table). cape7isis, Cy.stiscu.s, 629, 630. Hyaliiia (CysHscus) , (629), (630). Marginella, {629), (630). "Marginella," 629, 630. capitatus, "Monoplex," 734n. Capsa, 363 (twice). Capulids; 788. Capulus, 788. Cardiacea, 302-315. Cardiidse, 13, 302-315. cardiiformis, V erlicordia , 266. cardioidcs. Eryrhin, 299. Cardiomya, 265. Cardita, 272-276, 276, 276, 277, 277, 278, 2?S, 4Z7. Cardilacea, 272-279. Carditamera, 277, 277, 278. Carditids, 13, 272-279. carditoides, Peiricola, 366, 357, pi. 13, figs. 14o, 146. Saxicava, 355. Cardium, 134, 135n., 275, 301, 302, 302-303, 303, 303- 315, 313, 390, 393, 402, 403. Caribbean fauna, species, etc., 50, 94, 95, 96. carinata. Alia, (689), 692. Amy da, 692. Aslyris, 692. Columbella, 689, 692. Lacuna, 782-783. Mactra, 402n. Mactrella, (402n.). Mitrella, (689), 690 (three times), 692-694, 695, 697, 941, pi. 26, fig. 35. Relusa (Adeocina), 449. Spirotropis, 546, 547. Tornatina, 449. carinatum, Bnccinuni, 668. Plevrotoma, 546. Trilonium, 668. Carimdriliia, 485, 582. carinulata, Madra (Mulinia), 4OO, 4OI. Midinea, 4OI. carisaensis, Chorus, 727. Farreria, 727-728. Trophon, 727. carloUse, Lora, 511. Mangilia, 511. carloltensis, Macoma, 372,S72, 922, pi. 20, figs, la, lb, 2a, 2b. Tellina, 372. carlsoni, Priscofusus, 491. Turris, 491. carnarosensis, Yoldia, 129. carpenleri, Homalopoma, 821-822, 822, 823 (twice). Leplolhyra, 821. Tellina, 361. Tellina (Angulus), 361. Trifora, 766. Triphora, 766. carpenleri — coiiliimcd. Tiiphoris, 766. Turhonilla (Striohirbonilla) , 868. carpenter M7ia, Balhytoma, 495, 497. Dolichotoma, 497. Genota, 497, 499. Pleuroloma, 495, 497, 499. Pseudotoma, 497. Surcula, 495, 497. Turris, 495, 497. carpenterianus, Cryptoconiis, 497. Surcidites (Mei/asiircula), 493, (495), 4-96, 496, 497- 500, pi. 25, figs, -in, 46; s. s., 497-498. Carpinteria, 74, 75 (table). Carriio Creek, fauna, or Mountain, see Coyote Moun- tain; formation, see Imperial formation. carrizoensis, Peden, 224- Pecten (Janira), 224. carteriana, Astarle, 269. Caryatis, 344, 346. casenlina, Lora, 524- caseyi, Drillia, 489. Turricula (Pleurofusia) , (489). casmaliense, Bittium ( — ), 763. Caspa, 363. Caspian Sea, 303, n. cassidaria^formis, Siphonnlia, 646. Cassidids, 739-740. cassidiformis, Cancdlaria, 21, 617, 620-621. Cassis, 670, 639-640, 640. cassis, Acmsa, (810). castanea, Brachytoma, 583. Clavalula, (583). Leucosyrinx (Steiraxis) :', (509). Neptunea, 651n. Pleurotomella (Phymorhynchus) , 509. castaneum, Calliostoma, (833). castaneus, Beringirts, (651n.). Trochus, 833. Volutopsius, (651n.). castania, Pyrene, 681, 682. Casterlien, 69 (table). castianira, Clathrodrillia, 582. Claims (Crassispira), (582). castor, Cardita, 273. Venericardia, 273. castrensis, Acila, 116, 117. Nucula (Acila), 113, 114, 115, 116-117, 116, 117, pi. 1, figs. 6c, 6b. Catalina Island, see Santa Cataliua Island. catalinse, Anliplanes, 553, 554. Mitra, 636, pi. 28, fig. 4. Peden (Lyropeden), 30, 186, 186, 187, 896. Pleuroloma, 553. Spirotropis (Anliplanes), (553), (554), 555. Strigatella (Atrimitra), 636. catalinense, Bittium (Lirohitlium) , 759-760, 763. catalinensis, Alaba, 784. Bittium, 759. Farreria (Austrotrophon) , 707, 725, 726, 727. Trifora, 766. Triphora, 766. 972 San Diego Society of Natural History Memoirs catalinensis — continued . Triphoris, 766. Trophon {Austrotrophon), 726. Turhonilla [Mormula), 871, 872. calaphracta, Genola {Baihytoma), (502). cataphradus, Murei, 502. cataracles, Pecten (Euvola), 228. Peden (Janira), (228), 229. catena, Turricula, 487. catenatus, Conus, IfH, 474. Catenoscala, 861. catharia, Volrulella, 450. cathedralis, Ancistrosyrinx , [506). Candelabrum, 506. catilliformis, Madra (Sjnsula), 394, 398, 398-399, 404, pi. 23, figs. 4, 10. Pecten {hyropecten), 176, 177, 178. Spissida, 398. Spisula, 394, 398, 399. Spisxda {Hemimactra), 398. Calinus, 806. caucanus, Pecten {Aequipecten), 217, 218. caudata, Eupleura, 714. Ficula, 742. Ficus, (742). Ranella, 714- caurinum, Amusiu7ti, 194, 195. caurinus, Peden (Chlamys), 195. Peden (Patinopeden), 22, 35, 40, 61 (table), 96, 105, 192, 193, 194, 194-196, 194, 197, 198, 238, pi. 6, fig. 4. Cavilucina, 286 (twice). Cavolina, 440-441, 44O. Cavolinidse, 440. cedlix, Pecten {Propeamussium), 232-233. cedo-nulU, Andslrosyrinx, (506). Pleiirotoma, 506. Cedros Island, 50, 51. cedro&ense, Epitonium (Asperiscala) , 857. cedrosensis, Epitonium, 857. cellulifera, Mitra, 636. celhdita, Leda, 122. Nuculana, 122-123. Cemaria, 861. Cemoria, 851, 851. Cenozoic, later Cenozoic history, 19, 51, 77, 78; later Cenozoic marine sequence, 26; later Cenozoic orogenic movements, see diastrophic revolution of the middle Pleistocene; Lyell's classification of, 20. centifilosa, Protocardia, 311. centifilosum, Cardium, 311. Lssvicardium {Nemocardium), 311, 315, pi. 19, figs. 9, 10. Centinela gravels, 41. Centrifuga, 706-707. centrifuga, Murex, 706. Psevdomalaxis, 785n. Purpura {Centrifuga), (706), 707 (twice). Spirolaxis, (785n.). Centronolus, 731. Cephalaspidea, 442. cepio, Placunanomia, 24I. Pododesmus, (241)- Cerasloderma, 307-310. cercadensis, Nassarius (Uzita), 678. cerealis. Bulla {Tornatina), 44'^- Retusa (Adeocina), {44''') ■ cerina, Gouldia, 269. Mangelia {Bela), 595. Pleurotoma, 595. {Veneridse), 270n. Cerithidea, 763-764. cerithidioide, Biltium, 768. cerithidioidis, Alabina, (758). Cerithiopsida, 765. Ceritkiopsids?, 764-766. Cerithiopsidella, 765. Cerithiopsina, 765. Cerithiopsis, 760, 764, 764-766, 766. Cerithium, 468, 4?0n., 491, 756-757, 757, 757, 758, 761, 763, 766, 769n. Cerostoma, 705, 706, 708, 709n., 709n. cerritensis, Aledrion, 675. Aligena, 300. Nassa, 675. Nassarius {Schizopyga) or Nassarius (Tritia), 675. Neptunea, 721. Ocinebra, 711. Pecten {Aequipecten), {205). Pe ten (Chlamys), 206. Tritonalia, 711-712. Trophon (Boreotrophon) , 721. Cerros Island, see Cedros Island. cerrosensis, Forreria (Austrotrophon) , (726), 726. Ostrea, 150. Peden (hyropecten), 21, 30, 33, 34, 40, 46, 98, 182, 184, 187, pi. 8, figs, la, 16, 2a, 26, pi. 9, fig. 2. Pecten (Plagiodenium), 187, 211 (twice), 212, 219. Trophon, 726. cesta, Mangelia (Bela), (692). Mangilia, 592. cetolaca, Mangelia (Bela), (591), (704). Mangilia, 591, 704. Chalky boulder clay, 67, 68, 69 (table), 71. Chama, 272, 276, 277, n., 279-280, 280, 281, 283, 328, 350. Chamacea, 279-281. Chamids', 279-281. Channel Islands, 26, 39. charana, Turrilella, 775. Chauvetia, 589, 600, 685, 686-688. chehalisensis, Acteocina, 446. Adeon, (446). Dnllia, 491. Leda, 126. Nuculana, (126). Priscofusus, (491). Cheilea, 794. CheUean culture, 68, 69 (table). Chemnitzia, 866, 867, 868, 869, 870, 871. chemnitzii, D-ivaricella, (295). Luaina, 295. chiachiana, Lora, 629, 630. Chicoreus, 706, 707, n., 715, 728, 728-731. Chief terrace of the Rhine, see Rhine. Volume I ] Pliocene and Pleistocene Mollusca of California 973 childrenx, Lucina (Millha), 96, 291 (three times). childreni, Lucina {Millha), 291 (twice). Phacmdes {Millha), 291. Tellina, 391. chilensis, Malletia, 132. Ostrea, 154. Venus, 354. Chillesfordian, 69 (table). chinensis, Calyplrsea, (794). Patella, 794. Chion, 378. chionsea, Callisla, 347. Cylherea, 347. Dione, 347. chionsnis, Pilar {M egapilaria) , {347). Chione, 316, n., 317, 318-324, 329, 331, 331, 335, 336, 343. Chione elsmerensis zone, 52, 61 (table). Chionella, 343ii., 347. Chironia, 299-300, 302. Chitons, 87S. Chlamys, 157, 158, 159, 160, 160, 161-170, 170, 171, 171, 173, 174, 175, 176n., 177, 188, 189, 190, 191, 191, 192, 195, 198, 199, 199, 200, 202, 203, 204, ^05, 206, 221, 232, 235, 902. Chlorosloma, 825-831, S31, 831, 834. Chorus, 725, 725, 720, 727. Chrysallida, 872-873. chrysalloidea, Amyda, 703. Aslyris, 703. Columbella {Aesopus), 70S. chrysalloides, Aesopus, 70S. chrysalloideus, Aesopus, 703, 703. chrysis, Panope {Panomya), 426, 427. Chrysodomus, 64I, 642 (twice), 645, 647, 648, 651, 653 (three times), 654, 655, 656, 657, 658, 659, n., 660, n., 661, 662, 663, 664, 665, 713, 714, 715, 716. chrysolhemis, Cryptogermna, 548. Spirolropis, 548, 548. Cidarina, 838, 839. cidaris, Cidarina, (838), 838, pi. 32, fig. 22. Margarila, 838 (twice). Solariella, 838. Turcicula ?, 838. Cierbo formation, 59. cierboensis, Pecten, 200. Pecten {Aequipeclen) , {200), 201. ciliatum, Cardium, SOS, 310. Lsevicardium {Cerastoderma), (308), 310, pi. 19, fig. 11. cinerea, Bela, 519. Defrancia, 519. Lora, 517, 519. Margarita, 84O. Margariles {Pupillaria) , 84O. einereus, Margariles {Pupillaria), 840. Turbo, 840. Cingula, 767. cingulifera, Turris, 505, 569, 571. cinnabarina, Chlamys, 161. Ostrea, 161. dnnabarinus, Pecten, {161), {162). cinnamomea, Bolula, (252n.). Modiola, 252n. Cinulia, 44^. circinala, Aforia, 608. Leucosyrinx {Aforia), 508. Circomphalus, 333. circularis, Pecten { — ), 218. Pecten {Aequipeclen), 97, 205 (twice), 206, 211, 212, 213, 214, 215, 216, 217, 217, 218-219, 220 (twice), 220, pi. 5, figs. 7a, 76, 7c. Pecten {Chlamys), 218. Pecten {Dentipecten), 218. Pecten {Plagioclenium), 218, 219. eircumtexta, Trilonalia, 713. cirilli, Cirillia, {609). Raphitoma, {609). Cirillia, 609. Cithara, 588, 603. cilharella, Cancellaria, 602, 603. Cythara, {602), {603). Mangelia, 602. ciiilella, Odostomia {Evalea), 875. Clallam formation, 59. clallamense, Trophosycon, 750. clallamensis, Ficus {Trophosycon), 746, 747, 748 (twice), 749, 750-751, 948. Pecten (Propeamussium) , 233. Venus (Chione), 320. clandeslina, Cryplospira {Cyprxolina), 629, 632. Hyalina (Cyprxolina), (629), (632), 633. Clark, B. L., 8, 9. clnrki, Chrysodomus, 656. Epilonium (Asperiscala) , 857. Macoma {?), (256). Neptunea, 656. Periploma, 256. Pilar, (344), 345. Pilaria, 344. clarkiana, Bathyloma, 497. clarkianus, Surculites {Megasurcula), (497), 498, 499. Classification, 13, 85-90, 92-93, 478-480; zoological characters upon which classification is based, 93, see also radulse, opercula, protoconchs, plications on the columella, shell characters, and variation. clathrala, Daphnella, 542, pi. 25, figs. 23, 24. "Drillia," 583. clalhratus, Trophcm (Boreotrophon), 721 (twice). Clalhrodrillia, 481 (diagram), 482 (twice), 484n., 485, 485, 4S6n., 549, 564, 565, 565, 566, 567, 569, 577n., 579-580, 581, 582, 582, 600, 605, 938. Clathromangelia, 600, 604- Clathromangilia, 526, 599. Clalhurella, 481 (diagram), 483, 510, 511, 575, 577, 585, 586 (twice), 587, 600, 601, 604-608, 6O4, 608, 609, 610 (four times), 610n., 623, 686; s. s., 481 (diagram), 604-608. Clathurina, 609. clausa, Natica (Cryplonatica) , 797, 798. Natica {Tectonatica) , 35, 797-798, te.\t fig. 11, (798), 799, 805. Clausina, 318. Clava, 574, 756, n., 758. clavala, Ostrea, 174- 974 San Diego Society of Natural History [ Mbmoihs clavator, Cabestana (Ramila), (734n.). Murex, 73^n. Ranula, (734n). Ranularia, (7S4n.). Ciavatula, 478, 479, 480, 481 (diagram), 482, 482-486, 482, 486, 487, 509, 559 (twice), 574, 574, 575 (twice), 579, 581, 582 (twice), 583 (twice), 587, 590, 604, 605, 010, 611 (three times), 934, 938; s. s., 481 (diagram), 482-483, 484, ciavatula, Cancellaria, 615, 615-616, 616, pi. 27, fig. 2. clavatus, Pecten (Pallium), (174). C avicantha, 574- clavicularis, Pleuroloma, {611). "Tomdla," 611. Glands', 756-764. Claims, 479, 480, 481 (diagram), 483, 485, 489, 504, 514, 547, 559 (twice), 563, 565, 574-684, 584, 585, 586, 590, 605, 610, 938 (twice) ; s. s., 481 (diagram), 574-575. Claims (Crassispira) , sp., 582, pi. 26, fig. 10. clavus, "Munx," 725n. dementia, 323, 325, 327, 333-335, 351, 406; «. s., 333, n., 333, 334, 335. Clidiophora, 262. Clidophora, 262. Cliids, 440-441. Cliinacopoma, 785. Climatic changes, correlation by, 19, 21-22, 36, 43, 70. Climatic optimum, 68, 73, 74, 75 (table). Clinopegma, 660-661. dintonius, Peden (Placopcden) , 192n. Clinura, 481 (diagram), 492, 493, 494, 495, 500, 501 (twice), 506. Clio, 440. Clionella, 564, 564, 566. dionella, Leucosyrinx (Surctdina), 510. Chsia, 629 (twice). Clypeus, 462. Clypidella, 849. Cnesterium, 128, 130, 130-132. Coachella Valley, 49. Coalinga, 51n., 52. coalingaensis, Pecten, 227. Pecten (Janira), ;34, 221, 227, 227, 228, pi. 2, fig. 2. coalingense, Calliostoina, 834. Trophon {Forreria), 728. coalingensis, Calliostoma, 834. Chrysodomus, 64I. Clavus (Clathrodrillia), 30, 580, jil. 26, figs. \ia, 14fc, 15. Forreria, 728, 728. Fusinus, 641. G ycymeris, 135. Mactra {Spisula ?), 399-400. Mytilus (Mytiloconcha), 21, 246, 246, 247. Nassa, 673. Nassarius (Schizopyga) or Nassariits (Trilia), 673. Pecten, see also coalingaensis and Pecten coalingeiisis zone; 227. Pleurotoma, 580. Spisula, 399. Turris Bathytoma), 580. coarctata, Cassis (Levenia), 740, 740. coarctaium. Cassis, 740. Coast Range mountain-building revolution, see diastro- phic revolution of the middle Pleistocene. Coast Ranges, 51, 54, 60, 62, 72. cobboldix, Nucnla (Acila), 113n. coccineum, Homalopoma, {822, n.). coccineus. Turbo, 822, n. Cochlea, 307. cochlearis, Pleurotoma, 504n. Turris (Pleuroliria) ?, (504n.). Cochlespira, 481 (diagram), 483, 504, 505-506, 506, 506. Cochlespiropsis, 505. Cochlodesma, 255. codak, Chama, 283. Codakia, {283). Codakia, 283, 284, 285, 289. Codakiacea, 281-297. Codakiidse, 13, 283-292, 292, (296, as Lucinidx). codok, Chama, 283. Codakia, {283). coelata, "Nucula," 121. coelehs, Conus, 473. coffea. Bulla, 461. coffeus, Melampu.'i, (461). cognata, Petricola, 356. Petricola {Petricolaria) , 356. Coleophysis, 445, 446. coli, Priscofusus, {491). Turris, 491. collaris, Columbella, 692. Mitrella, {692). Collisella, 810, 812. collisella, Turbonilla {Pyrgolampros) , 869. collomi, Thais {Nucella), 718. colmaensis, Chrysodomus, 659. Neptunea {Sulcosipho) , 659, 659. Colombellina, 680n. coloradoensis, Mactra {Mulinia), 4OI, 402. colpoica, Codakia, 283. Lara, 523. Lucina, 283. Strombina, 700. Cotpospira, 769. columba, Aphrodite, 313. Serripes, (313). columbaria, Ancistrosyrinx, 506. Pleurotoma, 506. Columbarium, 506. Columbella, 591, 679, 680, 681, 682, 683, 684, 686, 686, 687, n., 688, 689, 690, 691, 692, 693, 694, 695, 696, n., 697, 698, 699, 700, 703, 704. columbella, Erato, 754. Columbellaria, 679. Columbdlidse, 679, 679, 690. Columbellina, 680. Columbellopsis, 689, 691. Columbiana, Amphissa, (688, 700, as corrugata), 700, 701, 702, pi. 26, fig. 39. Lucina {Myrtea), {287). ' columbianum, Phacoides, 287. Columbus, 683. columna, Halislylus, 824. Volume I ] , Pliocene and Pleistocene Mollusca of California 975 columnse, Bulla, 437. Bull-US, (457). Coins, 660, 661-666; s. s., 661-662, 664 (twice). coins, Fusinus, (638). Murex, 63S. ComaTmondia, 609. comatus, Pecten, 160, 160. Cominella, 701. communis, Amiantis, 349. Amycla, 694. M argaritiphora, 147. Milrella, (694). Pleria (Pinclada), (147). commutata, Leda, 120. Nuculana, (120). comoxense, Cardium, 308, 309. Lsevicardium (Cerasioderma), (308), 309. compacia, Lacuna, 782, 783. compactus, Pecten, 218. Pecten (Aequipecten) , (218), 219. comparilis, Pecten (Aequipecten), 219. complanata, Angulatomitrella, (692n.). Arcularia, 671. Columbella, 692n. Milrella, (692n.). Nassa (Zeuxis), 671. complanatus, Alectrion (Hima), 671. Nassarius, 671-672. complicatus, Petalocmichus, TtB. composita, Thais (Nucella), (716). compositum, Buccinum, 716. compressa, Architectonica, 786, 787. Tellina, 361. Compso7tujax, 333-334. compta, Phasianella, 814 (twice). Tricolia, 814, 814. comptus, Conus, 474. Comstock, J. E., 9. concamerata, Pholadidea, 434, 434. Pholas, 434. concentrica, Cryptobranchia, 808, 809. Cryptoctenidia, 809. Lepeta, (808), 809. Lepeta (Cryptoctenidia), 809. Patella (Cryptobranchia), 809. conceplioms, Leda, 120. Nucula7ia, 119, 120, 120, 126. conchaphila, Ostrea, lo2. Conchocele, 281, 281. Conchology, 81. concinna, Murex (Ocinehra), 713. Pilaria, 346. Psephs-a, (633), 634. Tritonalia, (713). Valuta, 633. concinnula, Bela, 521. Lora, (521). concinnus, "Murex," 713. Pilar, (346). Concretions and nodules, 30 (twice), 58, 418. condonana, Bathytoma, 497n. condonanus, Surculites (Megasurcida), 494, 497. condoni, Arctoscala, 856. Epitonium (Boreoscala) , 856. Margarites (Lirularia), 841. Mytilus (—), 247. Pecten (Amusium), 230, 232. Thracia, 2.58. condoniana, Bathytoma, 49771. condonia7ius, Surculites (Megasurcida), (497n.), Conella, 679, 680 (twice). confusa, Nnculana, 121. conica, "ClavicarUha," 574. Pyramidella, 865. Scalaria, 852. ccmicum, Epitonium (852). Conidse, 445, 471-477, 480, 482, 501. Conidea, 680. coniformis, Bulimus, 461. Melampus, (461). conoidea, Bela, 529. Lora, (529), 534. Conopleura, 603. Conorbis, 501. Co7wt'ulus, 461. conradi, AHla, 117 (twice). Donax, 381. Glycy7/ieris, 135. Nucula (Acila), 116, (117), (117). Pholadidea, 433. Scaphander, 462, 452. conradiana, Clalhurella, 606-607, (607), 607, pi. 26, fig. 11. Cytherea (Transennella ?), 338. Glyphosloma, 606, 607. MangUia (Clathurella) , 606. Tra7isen7ie!la, (338), 339. consors, Cadium, 306. Lsevicardium (Trachycardium), 306. Natica (Cryptonalica), 797. Natica (Tectonatica), (797). constantia, Columbella (Aslyris), 695 (twice). Milrella, (695, twice). constricia, Mangelia ( — ), 592. contignata, Ficus (Trophosycon), 747, 748, 749, 751, pi. 29, figs, la, 16, pi. 30, figs. 1, 2, 4, 9a, 9&. conti/iuatum, Epitonium (Nitidiscala), 868. Epitoniu77i (Nitidoscala), 858. contorta, Calyptrssa, 794, 795. contraria, Pleurotoma, 554. Spirotropis (A7iliplanes) , (554), 555. contrerasi, Epitonium (Nitidiscala ?), 858. contusus, Donax, 381. conula, Calliosloma, 831. Conulariidse, 440. conidus, Calliosloma, (831). Trochus, S31. C071US, 471-477, 501, 680, 680. * coni'exa, Natica (Neverila), 797. Natica (Tectonatica) ?, (797), 798. Norrisia, (824). convexus, Trochiscus, 824- cooperi, Alectrio7i, 674, 675. Csecum, 779, 779. Cancellaria, 616 (twice), 619-620, 620. 976 San Diego Society of Natural History [ Memoirs cooperi — continued. Cancellaria (Narona), 619. Cancellaria (Progabbia), 619. DoHchotoma, 499. Drillia, 552. Genota, 499. Epitonium (Nilidiscala), 860. Nassa, 674. • Nassa (Trilia), 674. Nassarius (Schizopyga) or Nassarius (Tritia), (674), 674-675, pi. 26, figs. 40, 50. Pecten (— ), 213. Pecten {Aeqxiipecten) , 212, (213). Pecten (Plagioctenium) , 213. Pleuroloma, 499. Puncturella, 852. Schizopyga, 675. Sphsrium, 298, 299. Spirotropis (Atitiplanes), (552). SurcuUles {Megasurcula), 493, 499-500, pi. 25, fig. 3. Terebra, 465, 470. Turrilella, 44, 770, 771 , 771-772, 773, pi. 24, figs. 28-34. Volmdella, 450, 450. Yoldia, 128-129, 130, pi. 1, fig. 13, pi. 14, fig. 3. Coos Bay, 55, 56-57. Coos conglomerate, 54, 56, 57, 60, 61 (table). coosense, Argobuccinum (Fusilriton), 735. Carduim, SOS. Lsevicardium (Ceraslodernia), 308. coosensis, Cardium, SOS. Fusinu.^, 641. Mactra {Spisula), {396). Pecten (Patinopecten) , 21, 193-194, 194. Priscofusiis, 491. Ranella (Priene), 735, (735), 736. Spisula, 396. Turris, 491. cor, Corbicuh; (29S). Cyrena, 29S. Isocardia, 69 (table). coralina, Tritonalia (Ocinibrina), (709n.), (725n.). coralinus, Fusus, 709n., 725n. corallina, Mactra, 391. Coralline Crag, 66, 69 (table), 70. corallinoides, Pecten (Lyropecten) , 179, 179, 181. corallinus, Hinnites, 157. Pecten, (157). Pecten (Lyropecten), 179, 180. Corbicula, 68, 69 (table), 297, 298. corbicida, Tivela, (339). Venus, S39. corhiculata, Ranella (Priene), 735, 735-736, 736. corbiculatutn, Gyrineum, 735. cm-Ms, Cardium, 307, SOS. Cochlea, 307. Lxvicardium (Cerastoderma), 307-308, 309 (twice), 310, pi. 19, figs. 14, 17. Corbula, 222, 419-422; s. s., 419-421, 420n. Corbulids!, 419-422. corbvloidea, Thracia, 256, 257. corbuloides, Bornia, SOI. Thracia, 256. Corbulomya, 421. cordata, Neptunea, 657. cordalus, Chrysodomus, 657. cordieri, Cordieria, (609). Irus, (332). Petricola, 332. Pleuro'oma, 609. Raphitoma, 609). Cordieria, 544, 609. cornea, Lucina, 295. Neptunea (Colus), (661), (664, 665, — as type of Colxis). Tellina, 298. cornellanus, Pecten (Aequipecten) , 217 (twice). corneum, Sphserium, (298). corneus, Fusus, 661. Murex, 661 . Taras, (295). cornucopia, Hipponix, (788). Patella, 7SS. cornula. Cassis, (739, twice). cor?iut.um, Buccinum, 739 (twice). cornulus, "Monoplex," 734n. coronadoensis, Acleon (Rictaxis), 443, 443, 444. Delph'noidea, 844. corcnadm, Borsonella, 550, 551. Borsonia, 5.50, 551. Spirotropis (Bononella), 547, (550), 551, 651. coronata, Anachis, 685, 688, 688. Clavatxda, 482, 483, 484, 509, 583, 934, pi. 25, figs. 16ct, 166. Columbella, 685. Murex (Turris), 482, 583. Pleurotoma, 482. Turris, 483. coronatus, Fusus, 4S2. "Typhis," 725n. Coronia, 570. corpulentum, Agasoma (Bruclarkia), (490). corpulodus, FiLiinus, (639). Fusus, 490 (twice), 639. "Fusus," 639. Correlation, methods of, 20-26; of California formations, 57-66 (table, 61); with the European section, 19, 68-76. corrugata, Amphissa, 688, 700, 701. Astarte, 268, 268. Cominella (Amphissa), 701. Crasttina, 268. Haliotis, 845. Mya, 119, 119. Nuculana, (119). Truncaria, 701. corrugalum, Buccinum, 700, 701. "Buccinum," 700, 701. cortcsyi, Hinnites, 154, 159n. Pecten, (154), 159. corteysii, Hiimites, 154. Pecten, (154). cortezi, Venus (Chione), 323. corteziana, Glycymeris, 136-137. corticata, Oliva, 623, 623-624, 624. cosibennis, Pecten (Palliim), 173. Volume I ] Pliocene and Pleistocene Mollusca of California 977 cosmia, Cerithiopsis, 765. Columbella, 683. Pijrene, (683). CoS7moco7icha , 701, 702. costata, Barnea (Scohina), 431. Cylichna, 452. Legiiminaria, 386. Mangelia (Bela), (589), (589). Melatoma, 564. Pholas {Barnea), 431. Pleuroloma, 589. Ranella, (734n.) or (734n.). Siliqua, (3S6), 388, 389. coslato-squamosa, Venerupis (Protothaca) , (329n.). Venus, S29n. costatum, CalUostoma, 833, 833-834, 834, 954, pi. 32, fig. 25. Cardium, 302, 303. costaius, CvUellus, 389. Monoplex, (734n.) or (734n.), Murex, 589, TS4n. Pholas (Barnea), 431, n., 431-432. Scaphander, (452). Trochus, 833. "Trochus," 833. costellata, Anachis ( — ), 689. Calyplrsea, 795, 796. Cahjplrsea (—), 795. Calyptrsea (Trochila), (795), 950. Trochita, 795. costifer, Trophmi, 644- costifera, Kelletia (Searlesia), (644), 645. costiferum, Trophon, 645n. costulata, Astra'a, (817n.). Mangelia (Beta), 585 (twice). Miirella, 689. costulatus, Trochus, 817n. couthouyi, Admete, (622), 622. Cancellaria, 622 (twice). couiitzensis, Surcvla, 4S0n. Turricula (Pleurofusia) , 490. Coyote Mountain, 49-51, 212. cracherodii, Haliotix, 846-847. Crag deposits of England, see Coralline Crag, Red Crag, Icenian Crag, and Norwich Crag. cranchii, ''Bela," 589. cranioides, Hipponix, 788. Cranopsis, 851. crassa, Cancellaria, 619. Didacna, (303). Hinnites, 160, 161. Mya, 411, 414, 415. Myoconcha, 246n. Unio, 414. Venus (Chionc), 322. crassaspera, Mangelia (Mitromorpha), 592, 599, 699. Crassatella, 270, 271, 271, 390. Crassatellites, 270, n., 270-272. Crassatellitidse, 269-272. crassalelloides, Cytherea (Trigonella) , 340. Pachydesma, 34O. Tivela, 340, 396. n'assicardo, Liropecien, 183, 184- Pallium, 175, 183, 185. Pecten (Lyropeclen) , 21, 175, 178 (twice), 182, 183, 183-184, 185, 185, 186, 186, 188, 191, 900, pi. 9, figs. 4, 5. anssicostata, Cardita, 276, 275. Venericardia, 275. crassicostatus, Peclen, 191. crassidens, Aslarte, 274- Cardita, 274. Venericardia, 274- Crassilahrum, 725n. crassilabrum, "Murex," 725n. Crassina, 266, 267, 268. Crassinelki, 269-270. crassiplicatus, Pecten, 160-161. Pecten (Chlamys), 160. crassiradialus, Pecten (Lyropecten), (186). Pecten (Plagioctenium), 186. Crassispira, 481 (diagram), 553, 579, 580-582, 583 (twice), 583, 584, 605, 938. Crassopleura, 581. crassum, Cardium, 303. crassus, Pecten, (160), 160. Pecten (Hinnites), 160. cralilia, Diodora, 850. crau'fordiana, Cancellaria, 614-616, 618 (twice). Progabbia, 614- Crawjordina, 614-615. crebraria, Mitrella, (696). Nitidella, 696. crebricinctum, Csscum, 779 (twice). Micranellum, (779), 779-780. crebricostata, Cardita, 273-274, 274, 275. Mangelia (Bela), 593, 594. Mangilia, 593. Neptunea (Beringius), 651. Nitidoscala, 858. Scala, 858. Scalaria, 858. crebricostatum., Epitonium (Nitidiscala), 868-859. Epitonium (Nitidoscala), 858. crebricostatus, Beringius, (651). crebrifilata, Chemnitzia, S70. Turbonilla (Pyrgiscus), (870), 871. crebristriata, Irenosyrinx, 509. Leucosyrinx (Steiraxis), (509). crenatoides, Epitonium (Dentiscala), 855, 855. Opalia, 855. Crenella, 264. creninmrginatum, Epitonium (Dentiscala), 855. crenulata, Daphnella (Antimitra), 596. Fissurella, 848. Lucapina, 848. Macrochasma, 848. Megathura, 848. Crepidula, 789-793. Crepidulidse, 789-793. Crepipatella, 792. crelacea, Neptunea (Colus), (664). Cretaceous sediments, 26, 47, 414n. cretaceus, Buccinum, 664. I 978 San Diego Society of Natural History i Memoirs cribraria, Cohimhella, 696. Milrella, (684), {696), {697). "Nilidella," {684). cribrarivm., Buccinitm, 696, 697. Crickmay, C. H., 43. cris-pa, Admete, 622, 6SS. Turns, 505. ciiKpala, Mya, 432. Pholas (ZxTJsa), 432. Polytro-pa, 717. Purpura, 717. Thais (Nucella), (716), (717), 717. Zirfsea, 432. Zirphsea, 432 (twice), 433, 434, 435. crispatum, Buccinuni, 716. crispatus, Murex, 717. Pholas {Zirjxa), 432, 432, 433, (433). Crisposcala, 858. crispus, Pholas (Zirfsea), (432). Solen, 432. crista a, Ancistrosyrinx, (505), (506). Cochlespira, 505, 506. Pleuroloma, 505, 506. cristatus, Pecten (Amusium), 95, 231. cristella, Psettdochama, 280. aistobalensis, Pecten (Aeguipecten), 208, 209, 210, 210, 211, 890, 896, pi. 5, fig. 2. Peclen (Plagiodenium), 210. crocea, Airicula, 147. Plena, (147). Cromer, marine sands at, 67, 69 (table), 71. Cromer forest bed, 67, 69 (table), 71. Crucibulum, 793, 813. cruHfera, Fissiirella, 847, 848. cruenlata, Anachis { — ), 688. Ranella, 734. crumena, Astyris (Plectaria), 689. Milrella, (689). Crypta, 789. Cryptobranchia, 808-809. Cryptoconus, 481 (diagram), 492, 493, 495, 495, 496, 497, 498, 499, 500, 501, 502. Cryptoctenidia, 808, 809. Cryptodon, 281, 282, 404, 404. Cryptogemma, 504, 511, n., 548, 570 (three times), 571. Cryptomya, 413, 416-419, 419. Cryplomya californica zone, 52, 53, 61 (table), 399, 418, 928. Cryptonatica, 797, 798. Cryptospira, 629 (twice), 632. cryslallina, Clathurella, 607-608. Philbertia, 607. Tellina, 359. Ctenobranchiata, 464-877. Clenodontidse, 110. Cucidlsea, 133. Cucullseidie, 133. cucidlala, Puncturella, 851-852. Rimula, 851. culcitella, Acteocina, 447 , 44S- Bulla (Akera), 447. Rclusa (Acteocina), 447-448, (448), pi. 24, fig. 13. Cidtellus, 384, 385, 387, 387, 389. culler, Donax, 381. cumingi, "Typhis," 725n. Cumingia, 377-378. cumingiana, Ostrca, 150. cumingii, Placunanoynia, 242, 243, 243. Turritella, 774- cuneata, Astarte, 266. Rangia, (409). cuneatus, Gnalhodon, 409. cuneiformis, Nucula, 112. cunninghami, Lora, (631). Pleuroloma, 531. curia, Borsonia, (545), 546. Columbella (Alia), 690. Eupleura, 714. Gymnobela, 524n. Milrella, (690), 691. Pleuroloma, 545. Thracia, 258-259. curium., Cerithium, 757. Thericium, (757). Cuspidaria, 265. Cuspidariidse, 265. cuspidala, Corbula (Lentidium ?), 420n. Cuspidaria, (265). Tellina, 265. cutacea, Caheslana, (732). cutaceus, Aquillus, 732. Murex, 732. Triton, (732). cuvieri, Cardila, 275. Venericardia, 275. Cyathodonta, 255n., 257, 259-260. Cydas, 287, 295, 298, 301. Cycles, see sedimentary cycles, igneous cycles, etc. Cydocardia, 272 (three times), 273, 274. cycloides, Dosinia, (361). Venus, 351. Cyclopecten, 236. Cyclosloma, 862. Cyclostrema, 843. Cyclnslrematidse, 843-844. Cydostremella, 844, 844. cyclus, Clava, (758). Potamides, 758. Cylichna, 452, 452-455, 460, 460. Cylichnella, 453, 453, 454- Cylichnus, 452. cylindracea. Bulla, 452, 453. Cylichna, (452), (453), 453, 454- Defrancia, 64O. Lora, (64O). Cylindrella, 452, 452. cylindrica, Volvula, 450. Volnddla, 450, 450, 450. cymala, Lora, 515, .531, .533, 534. Psephidia, 337-338. Cymatiidx, 8, 13, 731, 732-739. Cymatium, 653, 654, 655, 732 (twice), 733. Cymatoayrinx, 481 (diagram), 514, 547, 559, 563, 575, 575-579, 579, 583, 584, 586, 590, 605, 938. Volume I ] Pliocene and Pleistocene Mollusca of California 979 cymbiformis, Haminca, J,5S. Haminoea, 468-460, 460. cymhvlus, Alys, J/oln. cymica, Thais (Niicella), 717. cymodoce, Clatlmrella, (606). Glyphostoma, 606. cyniothoe, Cryptogctmna, 548. Spiroiropis, 548. ajnocephalus , Cabcstana (Gutlurnium) , (734n.) or (7S4n.). Cabestana (Monoplex), i7S4n.) or (734n.). Monoplex, {7S4n.). Cyprsa, 628, 752-763, 753, 753, 754, 754. Cyprseidse, 752-754. cyprseola, Erato, 754. Cyprs!oU7ia, 629, 630, 632-633. cypria, Venus (Chione), 324. Cypricardia, 357. Cyprina, 281. cyprinus, Anatina, (406). Mactra, 4O6. Cyrena, 398. cyrene, Mangelia (Bela), 596. Mangilia (Kurtziella), 696. cyrenoides, Rangia, 409. Cyriodaria, 429, Cystiscus, 628, 629, 630-632. cystiscus, Hyalina (Cystiscus), (629), (630). Marginella, 629, 630. Cythara, 481 (diagram), 482, 483, 585, 586, 587, 601, 602-603, 604, 605, 610n. Cytharella, 587, 589 (twice), 590, 600, 601. Cytharopsis, 603. Cytherea, 316, 334, 340, 343, n., 344, 345, 346, 347, 348, 350, 351, 354. D Dactylina, 430. dactylis, Bidla, 457. Bullus, (457). dactylus, Pholas, 430, 431n. dalei, Buccimim, 666. Liomesus, (666). dallasi, Epitmiixim (Asperiscala) , 867. Odostomia (Chrysallida), 873. Peclen, 51, 169-170, 201. dalli, Amiantis, 349, 349-350. Barleeia, 786. Borsonella, 551 (twice). Borsonia, 551 (twice). Cxcum, 779. Cardium, S07n. Columbella (Nit della ?), 695. Dentalium, 438. Haminoea, 458, 459. Kellelia (Searlesia), 646. Lsevicardium (Trachy cardium), (307n.). Mitrella, (6.95). Pitar, 345 (twice). "Pleuroloma," 550, 551. dalK — continued. Pleurotoma (Borsonia), 550, 551. Rissoina, 769. Soleniya, 110. Spirotrojris (Borsonella), (560), (561). DaUinella, see occidentalis. dama, Oliva, 625, 626. Olivella, (625), 626. Vohda, 626. damon, Chrysndom^is (Ancistrolepis) , 660n. Neptunea (Sulcosipho), 660. danse, Mangelia (Beta), (596). Mangilia (Kurtziella), 696. danvillensc, Homalopoma, (823). danirillensis, Leptothyra, 883. Tegula (—), 831. Daonella, 147. Daphnella, 481 (diagram), 609, 542, 590, 596 (twice), 596, 597, 598, 599, 665n. darwini, Venus (Chione), (319 ?), 320. Daun stadium, 74. dautzenbergii, Colas, 662. Neptunea (Colus), (662). Davenport, C. B., 155, 209, 216. darndsoni, Peclen (Propeamusium), 234n. Pecten (Propeamussium) , 234, 237. Peclen (Pseudamusium) , 234n. dawsoni, Cardium, 310. Lxvicardium (Cerastoderma) , (310). Deadman Island, 36, 42, 43, 45, 377n. Deadman Island "Pliocene," 36, 37, 40, 41, 43, 63, 71. dehile, Sinum, 806-807. debilis, Sigaretiis, 806. decemcostata, Neptunea, 651, 655. decemradiata, Ostrea, 179. decemradiatus, Pecten (Lyropeclen), (179). decipiens, Pododesmus, 24I. decisa, Amphidesma, 376. Nucida (Acila), 113n. Semele, 376, pi. 14, figs. 1.3a, 136. declive, Tritonium, 629. declivis, Bela, 629. Lora, 515 (twice), 517, 519, 529, 529-530, 937. decora, Ancistrolepis, 660n. Neptunea (Sulcosipho), 660. Psammobia, 383. Sanguinolaria, (383). decoratum, Cardium, 117n., 308. Lsevicardium (Cerastoderma), (117n.), 308 (twice), 308-309, 310, pi. 19, fig. 12. decussata, Bela, 534, 540 (twice). Bulla, 743. Crenella, 254. Ficula, 743. Ficus, (743). Lora, (522), (623), (624), 625, (634), {64O, twice). Mya, 419. Pleurotoma, 622, 524, 534. "Pleuroloma," 524. Purpura (Jaton), (707). Pyrula, 743. Sphenia, (419). 980 San Diego Society of Natural History [ MEMoras decussatvs, Ficus, 743. "Fmsus," 522. Murex, 707. Mylilus, 2oJf. deflorata, Asa-phis, (363). Ca-psa, (363). Venus, 363. Deformation, see diastrophic. deformis, Fusus, 652. Pyrulofusus, 652. Volutopsius (Pyrnlofitsiis), (652, three times). Defrancia, 510, 512, 513, 514, 515, 519, 521, 529, 533, 540, 6O4, 60S, 610 (twice). dehiscens, Lima, 239. Ldma {Mantellum), 239. dejanira, Mangelia (Bela), (596). Man ilia ?, 596. Deleclopecten , 236. delmontensis, Odostomia (Ividella), 873. delosi, Peclen (Aequipeden) , {203), 204. Peden (Chlamys), 203. PimciureUa, 852. Delph noidea, 844. De ta deposits, 33. detnissa, Ostrea, 162. Volsella (Brachidontes), (252). demissus, Brachidontes, 252. Peden, (162). demiurgjis, Peden (Aequipeden), 212, 216, 217, 219, 219-220. Peden (Plagiodenium) , 219. Dendraster, 34, 52, 55. Dendropoma, 77S. densa, Macrocallisia (?), 343. densala, Madra (Pseudocardium) , 21, (400), (402), 403- 404. Mulinia, 4OO, 402, 403. densidathrata, Diodora, S50. densilineala, Cuming-ia, 378. CythareUa (Agatholoma), 590. Lucina (Myrtea), (287). Lucinoma, 2ST. Mangelia (Bela), (590), 591. densilirata, Lucina (Myrtea), (287). densiliratus, Phacoides (Lucinoma), 287. densus, Crassatelliles, 271. Dentaliidse, 436-438. Dentalium, 436-438. dentala, DimriceUa, 96, 295-297, 908; s. s., 295-296. Janira, 222, 228. Lucina, (295), 295. Tellina, 295. Vola, 228. Zirphsea, 433. dentatus, Peden, 228. Peden {—), 228. Peden (Janira), (222), (228). Peden (Vola), 228. Pholas (Zirfxa), 433. denticula, Hemipleurotoma, 571. Pleurotoma, 571. denticulata, Donax, 378. Macoma, (374). Mangelia (Zelekia), (600). Pdricola, 355, 356-357. Pelricola (Pelricolaria), 357. Tellina, 374. Zetekia, 600. dentifera, Clathurella, (6O4), 607, 607. dentiferum, Glyphostoma, 6O4. Deniipeden, 218. Dentiscala, 855. Dentition, see teeth. depida, Acmsea, 812. Collisella, 812. Nacella, 812. Patelloida, 812. deplanata, Astrsea, (817n.). deplanatum, Astralium, S17n. depressa, Astrsea (Pachypoma), (820), 821. depressum, Pachypoma, 820. deserti, Peden. (Aequipeden), 30, 34, 208, 212-214, 214, 215, 217, 219, pi. 5, fig. 3; s. s., 212-213, 214, 215. Peden (Plagiodenium), 212. deshayesii, Turris, 505. desmia, Clavalula (Trachylochetus) , (485), 486. Pleurotoma, 485. despeda, Neplunea, (652), (653), 653 (twice), 657, 944, pi. 28, figs, lo, lb. despedum, Tritonium, 652. despedus, Chrysodomus, (653). Fzisus, 653, 944. devinda. Area, 141. diabloense, Calliostoma, (837n.). diabloensis, Amiantis, (350). Calliostoma, 837n. Calyplrsea (Trochita), 796. Dosinia, 353. Macoma, 372. Peden (Lyropecien), 183, 191. Peden (Vertipeden ?), (191). Polinices, 408. Tellina, 372. Thais (Stramonita ?), 716, n. Tivela (Pachydesma), 340n. Trophon, 716n. Venus (Callista), 350. diadenia, Metaxia, 766. Diadora, 849, 850, 851. Diala, 784. Diastems, 24, 26, 32, 43. Diastoma, 758. Diastrophic movements, of the lower Miocene, 57; of the middle Miocene, 59; of the upper Miocene, 23n., 29, 51, 52, 59-60, 62, 76n.; of the upper Pliocene, 36, 76n. (on 77). Diastrophic revolution, of the middle Pleistocene, 19, 23, 31, 36, 37, 40, 44-45, 48, 49, 50, 53, 55, 56, 57, 60-62 (table 61), 62, 69 (table), 71, 72, 73, 75 (table), 76n. (on 76 and 77); of the upper Jurassic, 37, 50. I Volume I ] Pliocene and Pleistocene Mollusca of California 981 diavlax, Antiplanes, 568. Moniliopsis, (568). Turris {Anliplanes) , 56S. Diherus, 253. dickersmii, Mya, 412, 413, 414. Spirolropis, 648. Turris, 54S. dictynna, Mangelia (Agathotoma) , (601). Philbertin, 601. Didaaia, 303. Didonla, 427. diegensis, Borsonella, 551. Borson a, 551. Bolula, 253. Cerithiopsis, 765, 766. Clathrodrillia, 569. Cylichna, 454, 454. Cylichnella (Bullinella), 454- Lora, 523, 523. Moniliopsis, (569). Odostomia (Chrysallida), 872. Olivella, 627. Peclen, 223. Pecten (Janira), 44, 223, 223-224, 226, pi. 3, fig. 4. Spirolropis (Borsonella) , 561-562. Volsella, (253). diegoana, Mactra (Spisula), 395. diegoensis, Dendraster, 34. Pecten (Janira), 223. diegoensis, Chrysodomus, 643, 653. Kelleiia, 643, 643-644, 644, (653). Diestien, 66, 69 (table). digueli, Crassalellites, 271. dilatala, Kelleiia (Penion), (642). Mamma (?), (368). Siphonalia, 642. Tellina, 368. dilatatum, Bittium (Lirobittium), 760-761, pi. 24, fig. 14. dilatatus, Tectarius, 817. dilleri, Argobuccinum, 735n. Pecten (Lyropecten), 193. Pecten (Patinopecten) , 21, 193-194, 194. Ranella, 96, 735. Diluvarca, 137 (twice). diluviana, Paludina, 67, 69 (table), 71, 75 (table). diluvii. Area, 69 (table), 137, 138. diminuta, Anachis ( — ), 688. diminutivus, Pecten (Aequipecten) , (202). Pecten (Plagioctenium) , 202. Dimyarian pelecypods, 154, 156. Diodora, 849-861, 851. Dione, 343, 345, 347, 343, 350, 916. dione, Amiantis (Hysteroconcha), (350). Venus, 350. Diplodonta, 293-295. dira, Euihria, 645. Kelleiia (Searlesia), (643), 646-646, pi. 28, fig. 6. Searlesia, 645. dire?, Claeus (Crassispira), 582. direcla, Volsella, (250). directum. Modiolus, 250. dirum, Bucdnum, 645. dirus, Chrysodomus, 643, 645. Searlesia, 645. Dischides, 438. discors, Columbella, 680 (twice). Modiolaria, (254), 904. Modiolus, 254. Mytilus, 254. Pyrene, (680, three times), 681, 683, 684 (twice), pi. 26, fig. 42. Retusa, 445- Venerupis (Protothaca) , (329). Venus, 329. Valuta, 680. discus, Architectonica, 786-787, pi. 32, fig. 27. Pecten (Aequipecten), .52, 95, 199, 200-201, 201, 202 (three times), 203, 888, pi. 4, fig. 7. Peclen (Chlamys ?), 200. Pecten (Plagioctenium), 200. Periploma, 256. disjuncta, Conchocele, 2S1. Thyasira, 281, 281, 282, 906. dislocata, Terebra (Acus), 468. Terebra (Strioterebrum) , 467 (twice), 468, 468, cf. pi. 24, fig. 19. dislocatum, Cerithium, 468. dislocalus, Peclen (Aequipecten), 215. Pecten (Plagioctenium), 216. dispar, Venerupis (Protothaca), (329). Venus, 329. dissimilis, Macoma, 366. dislans, Artemis, 351. Pecten (Pallium), 170. distinguenda, Codakia, 283. Lucina, 283. distortus, Pecten, 157, 159. Ditoma, 600. divaricata. Area (Barbatia), (144), 144. Byssoarca, 144. Crenella, 254. Divaricella, (29-5), 908. Lacuna, (782-783), 952. Lucina, 295. Nucula (Acila), 112, 113, 115, 116. Tellina, 295 (twice). Divaricella, 285, 296-297. diversa, Astarte, 269. Astarte (Gonilia ?), 269. Paphia, 330. Tapes, 329. Venerupis (Protothaca), (329). Diversity, theory of, 77-78. divisus, Solen, 385. Tagelus, (385). Docoglossa, 808-813. Docomphala, 843-844. dolabriformis, Mactra, 393, 397. Mactra (Mactrotoma), 393, n. Mactra (Simmnactra) , 393. Spissula, 393. Spisula, 393. doliarium, Calliosloma, (833). 982 San Diego Society of Natural History I Memoirs doUarius, Trochus, 833. DoUcholoma, 497, 49S, 499, 502. Doligotoma, 502. Dolimn, 740, 740, 741, 741. dolivm, Biiccinum, 741n. "Dolimn," (741n.). dombeii, Venenipis (Protolhaca), (328). Venus, 328. Donacidse, 378-381. donadformis, Mactra {Mulinia), 4OO, 4OI, 401. Mxdima, 4OI. Donacilla, 359, 359. donacina, Gompltina, (336). Tellina, 359. Venus, 336. Donax, 109, 332, 340, 378-381. Donovania, 686, 686. doris, Mangelia (Agathotoma), (601). Philbertia, 601. dormitOT, Conorbis, 501. Comis, 501n. dm-sata, Crepidula, 792, 792. Slrombina, 700. dosin, Chama, 350. Dosinella, 352. Bosnia, 316, 329, 330, 333, 344, 34S, 360-354. Dosinidia, 352, 354. doirsoni, Bela, 530. Lora, (516), (530). Pleurotoma, 516. draconis, MdaneUa, 862. Melanella (Balds), 862. Polinices (Euspira), 805 (twice). Drilia, 491. Drillia, 481 (diagram), 488, 489, 491, 509, 512, 545, 547, 549, 562, 563, 556, 668, 660, 661, 562, 563, 664, 565, 566, 667, 569, 674, 574, 575, 575, 576, 577, 57Sn., 579, 581, 582, 583, 583-584, 610n. Drilluia, 482. dubiosa, Cyathodonta, 259. Tegula (Chlorostoma), 827. Thrana (Cyaihodonla), (269), 259. duboisiana, Paludma, 68, 69 (table), 75 (table). dubuissoni, Hinnites, I64. Pecien, (154). dufrenoyi, Modiola, 247n. (Volsella ?), (247n.). dufresnii, Melanella, 861. dumbleana, Phos, 610n. dumbleanus, Phos, 610, 623n. duniblei, Pleuroloma (Clalhurella) , 610n., 623. "Pleurotoma (Drillia)," 610n. dunkeri, Artemis, 354. Cytherea, 364. Dosinia, 354. Dosinia (Dosinidia), 354. Dunkeria, 872. duodecim-lamellatus, Pecten (Propeamussium), 235. dupetil-thonarsi, Fitsi7ius, 638. Fusus, 638. dupontii, Conus, 680. Parametaria, (680). dussumieri, Ficus, (742), 742. Pyrula, 742n. Syeotypus, 742. dysera, Venus (Chione), 318. East Anglia, 66, 70. Eastern North America, fauna! migrations between, and California, 93, 95, 96, see also migration; glaciations, 75 (table). Eaton, J. E., 9, 24, 32, 38, 102. ehorea, Ledina, 120. Nuculana, (120), (120 ?). eboreus, Pecien (Aequipecten), 207, 210, 212, 214, 217. eburnea, Clathrodrillia, 464- DivariceUa, 96, 285, 296, 296-297, 297, pi. 14, figs, lo, 16. Drillia, 563, 664. Imdna, 296, 297. "Pleurotoma," 564. Pseudomelatoma (Lsevilectum) , (563), 564. Vermicularia, 776-777. Eburneopecten, 235. eburneus, Vermetus, 776. ecarinala, Lora, 515, 517, 519, 530, cf. pi. 25, fig. 20. Echinarachnius zone, 52. echinata, Clavatula, 574. Clai, 7nacroschismii.-i, Pododesmiis, 242. macrosioma, Mela, 680. Parametaria, (680). Madra, 222, 390-404, 404, 405, 406, 407, 408; s. s., 390-393, 397, 400, 403, 926, 928. Mactracea, 390-410. Mactrella, 96, 401, 401, 402, 926. Madrids', 8, 13, 390-410. madroides, Tirela, (339). Venus, 339. Madromeris, 394-400. madropsis, Thraria, 259. Madrotoma, 392-393. maculata, Axinsea, 136. Corbula (Lentidium), (421). Glycymeris, 136. Gyrina, 734- Ranella, (734). Solariella, 838. maculalum, Lentidium, 421. maculaius, Peduncvlus, 136. Trochus, 823. maculosa, Columbella, 699. PleuToloma, 488. Strombina, 699, 700 (twice). Surcula, 488. Turncula, 487, 488-489, 489, 559, 562, 575, pi. 25, figs, llo, life. 7naculospira, Comis, 475. macidosum, "Cerithium," 756. madisonius, Peden (Lyropeden), 176, 177, 178 (twice). M^era, 359, 359. Magdalenian culture, 68, 69 (table). rtiagellanicus, Peden (Placopeden) , 192n. Trophon, 720. magister, Forrena, 30, 727, 738, pi. 27, figs. 14(7, 14^. Trophon, 727. ?nagna, Cryptoctenidia, S09. Cryplomya, 417. Lepeta, 809. Margarites, 841. Neptunea (Sidcosipho), 657, 660-661. magnifica, Thracia (Cyathodonla), 2.57. magnificum, Cardintn, 312. Fragum, 312. magnific.us, Pecten (Lyropeden), 21, 178 (twice), 179, 180, 182, 182-184, 187, 188, pi. 9, fig. 1, pi. 10, fig. 6; s. .s., 182-183. magnolia, Peden (Lyropecten), 176, 177, 177, 178, 178, 183. magnum, Csecum, 780. Micranellum, (780). m.agnus, Ancistrolepis, 660. Chrysodomus, 660. Margarites, (Lirularia), (841). mahogani, Cunus, 474, 477. major, Arcularia, 670. Columbella, (682), 697. Columbella (Alia), 697. Mitrella, (697), 698. Nassarius, (670). Puncturella, 852. Pyreroe, 682 (twice), 684, (697), (697). Malea, 740-741. malleata, Strombella, 652n. malleatus, Volutopsius, 652. malleti, Clathurella, (604). Hemipleurotoma, (604). Pleurotoma (Defrancia), 604- Malletia, 132. mamillaris, Calyptrsea, 408, 794-796, pi. 32, figs. 24a, 24b. Helix, 799. Naica, (799). Polinices, (799). Mamma, 799. mammillaris, Calyptraa (Trochatella) , 794- Galerus, 794. mammillata, Acmsea, 810. manca, Odoslomia (Evalea), 876. Mangelia, 478, 481 (diagram), 482, 483, 508, 512 (twice), 515, 519, 520, 522, .526, 527, 527, 528, 530, 542, 572, 575, 584, 584, 686-601, 602, 603n., 604, 605, 686, 687,937; s. s., 481 (diagram), 513, 585-588, 599, 600, 601. Mangilia, 511, n., 518, 520, 526, 527, 530, 537, 548, 567, 572, ■577n., 685, 587, 588, 590, 591, 592, 593, 594, 595, 598, 599, 601, 605, 606, 607, n., 686, 704, 712. Mangiliella, 589, &01. Mansfield, W. C, 9, 211, 219. Mantellum, 239. Manupecten, 170, 170-174, 175 (three times), 900. maravignse, Clavus (Crassispira) ?, (581n.). Crassopleura, (581n.). Pleurotoma, 581n. Marchia, 725n. Marcia, 325, 325, 326, 327, 334, 334, 344, 345, 345. Margarita, 147, 838, 839, 840, 841, 842. margarita. Helix, 839. Margarites, (839). Marginella (Eratoidea), 628. margaritacea. Pandora, 260. inargaritaceus, Phorcus, 83In. 1002 San Diego Society of Natural History [ Memoirs margaritana, Dosinia, 353. Septifer, S4S. Turrite'.la, 111. margaritamis, Septifer, 248. Margaritana, 424. Margarites, 823, 834, 838, 839-842. Margaritifera, 147, 148, I4S. margaritifera, Margarita, 147. Margaritifera, 147, 148. Meleagrina, I4S. Pteria (Pinctada), 147, 148. Margariliphora, 147, 148. Margaritophora, 147. marganlula, Cyprxolina, 632. HyaUna (CypneoUna), {632), (633). Marginella, 628, 62S, 629, 629, 630, 631, 632. Marginellarius, 628. MarginelMse, 8, 13, 628-633. Marginellus, 628. Maria Madre Island, 51. marise, Chione {Ldrophora), 324. Venus {Chione), 324. mariana, lAttorina, 781. Turritella, 772, 773, 933. marmorata, Nilidella, 683. Pyrene {Nitidella), {683). marmoratus. Turbo, 815. marmorea, Actmea, 810. Diala, 784. Litiopa {Diala), 784. marmoreus. Conns, 471. marochiensis, Natica, 797, 797. marshalli, Ranella {Priene), 736. Martesia, 430, 433. Martesiinse, 433-435. martinensis. Claims {Crassispira) , 582. martinezensis, Mesalia, (769). Turritella, 769. martini, Calyplrxa {Trochila), 795, 796. dementia {Egesta), (323). Terebra {Slrioterebrum) , 46, 470. Venus, 323. tnartinicensis, Clathurella, (604), 607. Crassinella, 269, 270. Glyphostoma, 6O4. {Gouldia), cf. 270n. martyni, Cingula, 767. marylandicus, Pecten, 163. Pecten {Chlamys), 163n. matheu'sonii, Dosinia, 354. Mytilus, 246. Ranella {Priene /), 736. Mathilda, 769. Matthew, W. D., 9, 67, 86. maura, Mitra, 635 (twice). Turricula, 488. maurellei, Bela, 539. Lora, 539-540. ?naxfieldi, Neptunea, 715. Thais {Stramonita), {71,5), 716. maxima, Ischnida, 512. Lora, (512). Lutraria, 404, 406. maxima — continued. Mactra, 404. Ostrea, 154, 157, 220. Siliqua, {387). Venus, 341. maximus, Pecten {Janira), 154, 157, 175, 220. Saxidomus, {341). Schizothsrus, {404), (40-5). Solen, 387, 387. Tresus, 404. mazatlanica, Lucina {Myrtea), 289. Margaritifera, I48. Margariliphora , I4S. Meleagrina, I4S. Pteria {Pinctada), 148. mazatlanicus, Phacoidcs {Here), 289. Mechanics, 81. media, Siliqua, 388, 389. mediacostatus, Pecten {Lyropecten), 186. mediate, Cerithium, 491. medialis, Apolymetis, {364). Arcopagia, 364. Fusus {Priseofusus) , 491. Priscofusus, 491. mediocre, Gyrineum, 735, 736. mediocris, Ranella {Priene), 735, {735), 736. mediostriata, Venus {Chione), 321. mediterranea, Corbula {Lentidiiim) , 421. Solemya, 109. Solenomya, 109. medius, Cullellus, 389 (twice). Solen, 388. meekianum, Cardium, 308, 310. Lsetricardium {Cerastoderma), (308), 310. meckii, Pecten (Palinopccten), I94. Megapitaria, 343, 346-348. megaspira, Psephsea, (633), (633). Valuta, 633. Megasurcula, 481 (diagram), 492, 493, 494, 495-500, 500, 501 (twice). Megatebennus, 848-849. Megathura, 848. Megayoldia, 127. viegodcm, Ostrea, 150. Melampus, 461. MJanella, 881-864; s. s., 861-863, S63, S64. Melanellidse, 861-865, 865. melanomathus, Chicoreus {Miiricattthus), (731). Mwicanthus, 731. melanura, Alaba, 784. Melarhape, 782. Melatoma, 480, 481 (diagram), 483, 559, 564. melea, Bellaspira, 584. Meleagrina, 147, 148, I48. meleagris, Columbella, 681. Pyrene, 681). melita, Hsedropleura, 584, 601. Mangelia {Agathotoma), (601). mellingloni, Mitra, 636. menardiana, Ishnula, {15), {512), 512, 937. Mangelia {Bela), section Ishnula, 15, 512, 585, 593 (twice), pi. 25, fig. 21. Volume I ] Pliocene and Pleistocene Mollusca of California 1003 mendenhalU, Peden {Aequipcclcn), 208, 211, 212, 212, 213, S17, 220. Pecten (Plagioctenium), S12, 219. Pinna, 146. mendica, Aledrion, 674, ('^S. Nassa, 674, 676. Nassa (Tritia), 674- Schizopyga, 674- mendicus, Alectrion (Schizopyga), 674- Nassarius (Schizopyga) or Nassarius (Tritia), 674-675, (676), 941, pi. 26, fig. 54. meneghinii, Pleuroloma, 573. Teres (Asthenotoma), (573). Menestho, 874. menzola, Odoslomia (Amaura), 877. mcrcatoria, Columhclla, (6S3). Pyrene (Columhella), (683), 683. Valuta, 683. Merced formation or series, 54, 55, 56, 60, 61 (table), 62, 69 (table). Merced River, 76n. (on 77). mercedensis, Clalhrodrillia , 569. Drillia, 569. Macira (Spisida), (.399). Moniliopsis, 569-570, 570, pi. 26, fig. 30. Spisula, 399. Turns, 569. Mercenaria, 317, 324, 326. mercenaria, Mercenaria, 324. Venus (Mercenaria), 316, 317, 324. Meretrix, 316, 340, 343, 345n.., 346, 3.'h, 350. meretrix, Cylherea, 343. Meretrix, (343). Venus, 343. Merica, 612, 622. meridiei, Chrysodomus, 645. Kelletia (Searlesia), (645), 645, 646. Merisca, 359-360. merita, Clathurella, 687. Clavatula, 587. Cytharella, 587. Mangelia, 587-588, 601, 607. Pleuroloma, 587. meropsis, Tellina, 359, 360, pi. 14, figs. 9a, 9fe, pi. 20, figs. 9a, 96. Tellina (Moerella), 359. Meroma, 629, 632, 633. merriami. Area (Barbatia ?), 142-143. Borsonia, (545), 563. Chrysodomus, 663. Dosinia, 352. Dosinia (Dosinella), 352. Drillia, 545. Macron, 650. Neptunea (Colus), 663-664. Pecten, 195. Pecten (Patinopecten) , (195), 198. mesal, Ceriihium, 769n. Mesalia, 769, 776. mesleri, Chrysodomus, 651. Volutopsius, 651. Mesochilostoma, 493n. Mesochilotoma, 493. Mesoplax, 430. Mesopleura, 385. mesotimeris, Pecten (Aequipccten) , 204- Mesozoic sediments, 55 (Jurassic) ; see also Cretaceous, dia.strophic revolution (Jurassic), and volcanism (Triassic). Meta, 680, n. Metaplax, 430. metaxa, Melaxia, (766) ?. Murex, 766. melaxse, Cerithiopsis, 766. Metaxia, (766 . Metaxia, 766. Metis, 363, 363, 364. metschigmmsis, Bela, 523. Lara, 523. Melula, 495. mexican-a, Olivella, 627. Ostrea, 150. Pyramidella (Longchxus) , 865. mexicamis, Longchseus, 865. Mexicardia, 305, 313. Mexico, see Lower California; 51; living faunas, see Gulf of California and Panama; 21; literature, 100. meyeri, Apolymetis, (363). Tellina, 363. micans, Eulima, 863. Melanella, 863. vnchseli, Ocimhra, 713. Tritonalia, (713). micheli, Ocinebra, 713. Tritonalia, (713). Micranellum, 779, 779-780. Microcithara , 680. microdonta. Area, 141. Microniactra, 393. middendorffi, Macoma, 372-373. Mytilus\ — ), 247. middendorffiana , Admele, 622, 622. middendorffii, Macoma, 372. middendorfii, Macoma, 372. , miga, Buccinum, 678. Nassa, 678. Nassarius (Uzila), (678). Migration of species, 13, 21, 90, 93-98, 159, (163), 172, 175-178, 179, 183, 189, 201, 215-217, 220, 222, 231, 271, 349, 388, 392, 394, 409, 412, 441, 454, 459, 468, 494, 579, 696, 735, 737, 786, etc. miguelensis, Pecten (Lyropecten), 177, 178, 185. milium, Anachis ( — ), 688. milleti, "Defrancia," 510. Miltha, 285, 291-292. Milthea, 291. Mindel glaciation, Mindelian, 67, 69 (table), 71, 75 (table), 76n. (on 77). Mindel-Riss interglacial, 72, 73, 75 (table), 76. mindoroensis, Cryplomya, (418). Mya, 418. minima, Anachis (C ha uvetia), (686, twice), 688. "Bela," 589. Columhella (Anachis), 688. Donovania, 686. 1004 San Diego Society of Natural History " Memoirs minimum, Buccinum, 686. Syntagma, (686). minor, Columbella, 689, 691. Columbellopsis, (689). Mactra (Pseudocardium), (40S). Mitrella, 685n., (689), (691). Midinia, 403. Mint Canyon formation, 28, 30, 31 (diagram). minuscula, Glans, 277, 277-278, pi. 13, figs. 10a, 106. minuta, Anachis, 686, (688). Columbella, 686, 688. Leda, 122. Nuculana, (122), 122, 12,5, pi. 1, fig.s. 2a, 26. Saxicava, (427). minutissima, Odostomia (Evalea), 875. minutus, Solen, 427. Miocene, diastrophism — see diastrophie movements, Alpine revolution, etc. ; fossils, 7, 30, 66, 68, 69 (table); interregional faunal migrations, 93-96, 97; sediments, 28-29, 31 (diagram), 36, 39, 40, 51, 54, 57-59; volcanism, 50, 58, 59. Miodon, 275, 275. Miodontiscus, 275-276. Miodontopsis, 275. miona, Lora, 515, 620. Miopleiona, 633 (twice), 634, 942. mirabilis, Acila, 113; see Nucula (Acila). Asiarte, 266. Nucula (Acila), 21, 113, 115, pi. 1, figs. 3a, 36. Rictocyma, 266. Milra, 633, 634-637. milra, Acmiea, 809, 810. milrala, Lora, 514, 515. Mitrella, 514, 683, 684 (twice), 685n., 689-698, 6S9. MitrUse, 482, 596 (twice), 633, 634-637. milriforme, Buccinum, 502. • mitriformis, Genota, (502), pi. 25, fig. 17. Murex, 502. Pleurotoma, 502. Mitrolumna, 596. Mitromorpha, 481 (diagram), 482, 586, 596-600, 600, 665n milrula, Bela, 514, 515. Lora, (514). Tritonium, 514. Mitsella, 689. Modelo formation, 28, 29. modesta, Admele, 622-623, pi. 27, fig. 5. Cancellaria, 622. Cancellaria (Sveltia), 622. Cosmioconcha, (702), 702. Ficus, 742, 743, 748. Mactra (Mulinia), 401-402. Moniliopsis, (567). Pyrula, 742. Tellina, 361, (362). Tellina (Angulus), 361. modestitm, Buccinum, 702. Calliostoma, (833). modestus, Angulus, 361, 362. Ficus, 742. }7)odestus — continued. Trochus, 833. Turris (Drillia), 567. Modiola, 247n., 24S, 249, 250, 251, 252n., 254. modiola, Spirotroj/is, 546, 547. Modiolarca, 253. Modiolaria, 253-254. Modiolus, 248-252, 254. modiolus, Fusus, 546. Modiola, 249. Modiolus, 249. Mytilus, 24s, 249. Volsella, (248), 249, 249, 250. modulatus, Pecten (Lyropecten) , ISO, 181. Moera, 3.59, 359. Moerella, 359. moesta, Anachis ( — ), 688. Drillia, 561. Macoma, 370-371, 908, 922, pi. 20, fig. 3. Pleurotoma, 561. Pseudomelatoma, 552, 559, 561, 561, 562 (three times), 564. Tegula (Chlorostoma), (826). Tellina, 370. moeslus, Trochus, 826. molinana, Macoma, 375. mollis, Conns, 4'73, 473. Mania, 241-242. monicensis, Alabiiia, 759. Melanella, 863. monilicosta, Cardita, 272. V enericardia (Cyclocardia), 272, 273. monilifera, Pleurotoma, 505. Surcula, 505. Turcica, 837. Turris (Gemmula), 505, 505. Moniliopsis, 481 (diagram), 483, 504, 526, 546, 547 (three times), 552, 553, 559, 560, 561, 564, 564- 570, 571 (twice), 573, 574, .582, 582, 665n., 940. monitata, Bursa, 731. monksse, Fusinus, 639, 640. Monoceros, 666, 719, 720. monoceros, Acanthina, (719). Buccinum, 719. Murex, 706. Murex (Cerostoma), 706. Murex (Pterorhytis) , 706. Purpura, 706. Monoculus, 440. Monodaaia, 303. monodactylus, Columbellina, 680, n. vwnodon, "Murex," 725n. Monodonla, 827, 830. Monomyarian pelecypods, 154, 156. Monoplex, 734, 737. monoptera, Hiatella, 4^7. Saiicava, (4£7). monotimeris, Pecten ( A equi pecten), 202, 203 (twice), 203, 204, 204, 204-205, pi. 4, figs. 3, 6. Pecten (Chlamys), 204. Pecten (Lepto pecten), 204, 305. Monotis, 147. montana, Dosinia, 926, pi. 22, fig. 3. Volume I Pliocene and Pleistocene Mollusca of California 1005 Montara Mountain, 55. inonterealis, Lora, 522. Monterey formation, 28, 31 (diagram), 38, 58. montereyana, Mya, 418. montereyense, Biltium (Stylidium) , 761. monlereyensis, Alvania, 768. Bittium (Stylidium), 761. Cerilhiopsis, 764. Chlorostoma, 831. Clat'iis (Crassispira), 581-582, 582 (twice), pi. 26, fig. 9. Drillia, 581. Miira, 635. Pleurotoma, 581. Seila, 764. Strigatetla (Atrimitra), 635. Tegula, (831). mo7itereyi, Chlorostoma, 831. Milra, 635. Semele, 377. Tegula, 829, 831, 831. Trochus, 831. Montesano formation, 22, 57, 59, 60; upper Miocene of Washington, 29. morani, Pecten [Chlamys), 173. Pecten {Pallium), (173), 173. moraniana, Nassa, 676. moranianus, Alectrion (Schizopyga), 676. Nassarius (Schizopyga) or Nassarius (Trilia), 676. morchi, Bela, 535. Lora, 535. Pleurotoma, 535. Taranis, (571), 572. Trophon, 571. mcrchianum, Buccinum, 669n. Mormula, 871-872. mortoni, Pecten (Amusium), 51, 95, 231. Mountain-building, 77. Mountain-valley stage in the Yosemite, 76n. (on 76 and 77). Mouretia, 462. Mousterian culture, 68, 69 (table). Mulinea, 401. Mulinia, 391, 392, 392, 400-402, 402, 403, 403, 409, 926; zone, 52. multicostata. Area, 30, 34, 139, 140, 884. Area (Anadara), 139. Area (Scapharca), 139. Borsonia (Eopleurotoma), (544n.). Cytherea, 316. Glycymeris, 133-134. Neptunea, 722. Pleurotoma, 544^- Trophon (Neptunea), 722. Venus (Antigona), 316-317, 317. mvlticostatus, Murei, 722. Pectunculus, 133. Trophon (Boreotrophon), 722, 723. Trophon (Neptunea), 722. midtifdosa, Tegula (Chlorostoma), 828. multUineolata, Mangelia (Bela), (589). Pleurotoma, 589. multiru^osus. Pectin, 159, 169-161, 168, pi. 11, figs. 5a, 55. Pecten (Chlamys), 160. multistriata, Puncturella, 852. multistrialus, Pecten, 157, 159. munda, Ocinebra, 712. Tntonalia, 599, 712, pi. 32, fig. 5. mundulus, Venerupis (Protothaca), (329). Venus, (329). murdochiana, Bela, 535. Lora, 535. Muretia, 462. Murex, 482, 486, 494, 500, 502, 503, 610, 512, 515, 579, 584, 585, 589, 608, 609, 610, 611, 637, 638, 649, 652, 653, 655, 661, 689, 690, 704, 705, 706, 707, n., 708, n., 709, n., 710, 711, 712, 713, 714, 715, 717, 722, 725, n., 726, 728, 729, n., 730, 730, 731, 732, n., 733, 734, "-, 7 41, 759, 764, 766. Muricanthus, 729, 731. muricata, Chemnilzia, 866. Clavalula, 483, n. Pinria, 144, 145. Pleurotoma, 4S3n. Turbonilla (Chemnitzia), 866. Turbonilla (Slrioturhonilla) , 866. muricatus, Murex, 725. Trophon (Trophonopsis) , (725). MuHcidse, 8, 13, 522, 642, 653, 704-731, 731, 732. Muricidea, 706, 709, 712, 713. muricidea, Mangilia, 599, 712. Tntonalia, (599), (712). muriciformis, Eupleura, 714. Ranella, 714- murina, Diadora, 850. Diodora, 860. Fissurella (Glyphis), 850. Fissuridea, 850. Murithais, 729, 729-730. mus, Diodora, (850). Fissurella, 850. muscaria, Venerupis (Protothaca), (329). Venus, 329. Musculus, 253, 253, 254, 254. mussatellus, Conus (Hermes), 471n. muta, Acila, 116, 117. Nucula (Acila), (116), (117). Mya, 53, 96, 97, 24Sn., 255n., 263, 299, 410-416, 416, 417, 418, n., 419, 4iy, 423, 4^3, 424, 4^5, 426, 427, 428, 432; s. s., 410-416. Myajaponica zone, 52, 53, 60, 61 (table), 69 (table), 70, 71; lower Mya zone, 52. Myacea, 8, 410-429. Myacids', 410^19. myalis, Nucula, 127. YoUia, 127. Myoconcha, 246. myrmacoon, Aesopiis, 703. Myrsus, 363. Myrtsea, 285. Myrtea, 285, 286-289, 290, 295; s. s., 286. 1006 San Diego Society of Natural History [ Memoir^ My sella, 301, 301. , Mysia, 293, 293, £9^. ' Mytilacea, 244-254. MytUicardila, 277. Myiiliconcha, 246. Mytilids', 244-254. Mytilimeria, 264. Mytiloconcha, 246. Mylilus, Ur, 150, 244-247, 2^7, 247, 248, 249, 250, 2-52, 253, 254, 4^7, 4^8, 429; s. s., 244-246. myluloides, Lithophaga, 253. Myurella, 466, 466, 469. myuros, Terebra (Mtjurella), 466n. N Nacella, 463, 464n., Sll, SI 2, 813. Jiahantensis, Siliqua, 97, 388, 389, 924, cf. pi. 21, fig. 9. nana, Clalhurella (Nannodiella), (608). NannodieUa, 60S. Philberlia, 60S. Purpura, 706. Thesbia, 541, (543), 698. Tritonium, 543, 698n. nanella, Hyalina (Cystiscus), {630), 631, 933. MargineUa, 630. NannodieUa, 481 (diagram), 591, 592, 608. Naguetia, 725n. Narona, 615-621. nashi, Tegula (— ), 831. Nassa, 670 (four times), n., 671, 672, (672), 673, 674, 676, 676, 677, 67S, 693, 694. Nassariidx, 13, 610, 670-679. Nassarina, 686. Nassariiis, 670-679, 694, 701; s. s., 670-672. nassula, Lucina (Myrtea), 288. nasuta, Macoma, 365-367, (373), 922, pi. 20, figs. 11a, 116. Mactra, 392, 405, 405. Tellina. 365, 373. nutans, Cavolina, 440 (twice). Natica, 796-799, 799, 799, 800, S02, 803, 804, 805, 807; s. s., 796-797. Naticarius, 796, 797. Natiddx, 8, 796-807. Naiicina, 803, 803. naucuni, Atys, (451n.). Bulla, 45 In. navarchus, Peden, (163). Pecten (Chlamys), 163. navicelloides, Crepidula, 792. Navicula, 142-143, I42. navicula, Donax, 379, 380. navisa, Odostomia (Iindella), (873). nazanensis. Lora, 534, 534. Nesera, 265. neahensis, Pecten (Lyropecten) , I84. Pecten (Plagioctenium) , 184- Nel^raskan glaciation, 70, 75 (table). nebula, Mangelia (Bela), 585, 586, (589, twice), 589. Murex, 589 (twice). Raphitoma, 589. nebulosa, BuUa, 457. nebulosum, Calliostoma, 833. nebulosus, Bullus, (457), (457). necropolitana, Cerithiopsis, 765, 766. Melanella, 863. neglecta, Venus (Chione), 322. Neilo, 124, 130, 132. Nekewis, 494- Nemocardium, 310-311. neohexagonum, Dentalimn, 436. Neovolvaria, 629. nephele, Clavus (Crassispira), 582. Neplunea, 647, 648, 651, n., 651 (twice), 652-665, 715, 716, 721-725; s. s., 652-657, 657, 658, 661. neptunea, Thais (Nucella), 717. Nepiuneidie, 8, 13, 482, 642-667, 667, 729. Nerita, 796, n., 807. Nerithea, 221. neritoides. Purpura, (715). Thais, 715. Nessea, 686. Nester terrace, 39, 49, 64. Netrum, 611. nevadanus, Pecten (Verlipecien), 188, 189-190, 191, pi. 7, figs. 2rf, 26, 2c. nevadensis, Pecten (Veriipecten) , 189. Tellina, 358, 358. Neverita, 797, 800, 800-803, 804, 805. Newbournian, 69 (table). newcombei, Mangelia (Bela), (593). Mangilia, 593. Pododesmus, 242. neivcombi, Nuculana, (126). Yoldia, 126. newcombiana, Callista, 345. Lioconcha, 345. Pitaria, 345. newcombianus, Pilar, 346-346, 346. newhallensis, Canccllaria, 618, pi. 27, fig. 7. Newport Beach, 8, 101. newsomi, Pecten (Aequipecten) , (218), 219. Pecten (Plagioctenium), 218. nicoli, Borsonella, 545. Borsonia, (545), 546. nifat, Fusus, 611. Perrona, 611 (three times), 612, pi. 25, figs. 12a, 126. niger, Musculus, 254. nigerrima, Crassispira, 583. Drillia, 583. Pleurotoma, 583. nigerrimus. Claims (Brachyioma ?), 683. nigra, Modiola, 254. Modiolaria, 264, 904. Pinna (Alrina), 146. nigrescens, Murex (Brontes), 704. nigricans, Anachis ( — ), 688. Turricula, 484, 489. Turricula (Knefastia), 484, 489. nigropunctata, Anachis ( — ), 688. Volume I ] Pliocene and Pleistocene Mollusca of California 1007 niloHcjts, Trochns, 823, 824. irhnbosa, Fissurella, (847). Macrocallista, (343). Patella, 847. Venus, 343. niobe, Cytharella, 601. Mangelia (Agalholoma), (601). nipponica, Thyasira, 906, pi. 13, fig. 15. nitens, Clavaiula, 590. Claims {Cymaiosyrinx), 590. Limopsis, (137). Lnciiin, 295. Mangelia. -590, 591. Pechmculus, 137. Taras. (295). nitenlior, Cadiilns, 439. nilida, Columhella, 6S3. NUidella, 684, 695. Pyrene (NUidella), (683), (684), 684 (twice), (695). Nitidella. 683-684, 6.95, 695, 696. Nitidiscahi. 8E7-860. Nilidoscahi, 857, 8.58, 859. nitidula, Columhella, 6S3n. Pyrene (NUidella), (683n.), 684. nivale, Pleurotoma, 549. nivalis, Spirotropis (Typhlomangelia), (549). nivea, Crepidula, 793. Pelricola, 356. Pleurotoma, 573. niveus, Teres, (573). Nivoly formation, 59. noachina, Patella, 851. Pundurella, (851), 851. noae. Area (Nancula), 137, 138n., 142. nobilis, Amiantis, (348), (349), (3.50). Architeclotdea, 785-78T, 954. Bela, 516. Defrancia, 515. Dione, 348, 349, 350. Ischnula, 513. Lara, (512), (515), 516, 517. nodalitia, Columhella, 681. Pyrene, (681). nodibulbosa, Ficus iTrophosycon), 746, 747, 748, 749, 7.50, 751, pi. 30, figs. 6'/, &>. nodifer, Ficus, 747. nodifera, Ficula, 744- Ficus, (743), (743), (744), 745 (three times), 746, (746), 746, 747, 748, 749, (751). Pleurotoma, 487. Pyrula, 743, 746. Turrieula, (487). nodiferous, Ficus (Trophosycon) , 751. 7iodiferum, Agasoma (Bruclarkia), (490). Trophosycon, 746. nodiferus, Ficus, 743, 746, 747, 751. Priscofu.ms, 490. Nodipecteii. 175, 175, 179, 181, 1S2, 187. Nodiscala, 855-856. nodocarirMta, Hemipleurotoma ?), (571n.). Pleurotoma, 571n. Nodopecten, 191n. 7iodosa, Haliotis, 845. Margarita, 8 2. Margarites (Ldrularia), 842. Osirea, 175, 179. Vermicularia ?, 777. nodosus, Margarites (Ldrularia), 842. Pecten (Lyropecten) , (175), 176, 178, 179-182, 182, 183,184,187,896; s. s., 179-180, 180, 182, 183, 187. Pecten (Nodipecten), 179. Vermetus, 777. nodulosa, Bela, 539. Lora, 539 Turritella, 774-776, 774- Nome, 57. nomeana, Thais (Nucella), 717. Nomenclature, of faunal zones, 43; of geologic forma- tions, 32; zoological, 81-82, 82-85, 85-92, 97-98, 156, 215-216, 478, 486-487, 494, 510-511, 512-513, 602-603, 604, 609-610, etc. Nomenclatorial speculation, 89, 94. Norfolk, 66. normale, Bucciuum, 668-669. norrisi, Norrisia, (824), 824. Trochiscus, 824 (three times). Norrisia, 824. norrisii, Norrisia, 824- noTvegica, Lyonsia, (263), 263n. Mya, 263, 426. Neptunea (V olutopsius) , 651. Panopsea, 426. Panope (Panomya), (425), (426). norvegicum, Cardium, 303. Lsevicardiu7n , (303 ) . norvegicus, Volutopsius, (651). Norway, 68. norwegica, Lyonsia, (263). Mya, 263, 435. Norwich Crag, 69 (table). Notovola, 221-229. nova, Turritella, 771, 772, 773; see also Turritella nova zone. novsezelandise, Pecten (Janira), 221. novaiasemliensis, Lora, 521. novaja-semljensis, Bela, 521. Lora, (521). Pleurotoma, 521. novemcostaia, Verticordia, (266). novemcostatus, Hippagus, 266. Nucella, 97, 715, 716-719. nuciformis, Odostomia (Amaura), 876. nvdeola, Cylichna, 455. nucleus. Area, 110. Corhula, 419, 420. Nucula, (110), pi. 1, figs. 4, 5. Pecten (Aequipecten) , 215, 217. Nucula, 110-117, 118, 119, 121, 122, 123, 124, 136, 127, ISO, 131, 132, 222, 880, 955; s. s., 110-112. Nu£ua (Acila), .sp., 115, text fig. 4. Nuculacea, 110-132. 1008 San Diego Society or Natural History Memoirs Nuculana, 96, 118-126, 120, 127, 127, 130; s. s., 118-120, 126. Nuculanidir, 110, 118-132. Nuculida-, 110-117, 118, l.i4. nummaria, Crepidula, 792-793. Crejndula (lanacus), T9£. nuncapatia, "Borsonella ?," 491. nunwakenliinea), 782. orthomorpha, Mactra, 96, 391-3S2, pi. 23, figs. 2(;, 2/(, 2c, 6, 7. Orthosurcula, 487. Orthoyoldia, 128. oryza, Aclseonidea, 44-^- Adeon (Rictaxis), (443). Osbeck, 154, 157-158. Oscilla, S74. Ostracea, 149-154. Ostrea, 149-164, 154, 157, 161, 162, 170, 174, 175, 179, 198, 215, 220, 229, 230, 231, 232n., 235, 239; ^ee also oysters. Ostreidie, 149-154. Otay terrace, 46, 47 (diagram). Otitoma, 609. ottitoma, Otitoma, 609. Raphiloma, (609). Oudardia, 361-362. oudardii, Tellina, 361. ovalina, Cytherea, 343n. Macrocallista (Chionella), (343n.). avails, dementia (Faventia), (334n.). Cryptomya, 417, 418, 924. Mactra (— ), 394 (twice). Mactra (Spisrda), (394, twice), 395. Mya, 418. Mya {Cryptomya), 417. Psephidia, 337, 337. Venus, 334n. ovata, Cancellaria, 612. Cytherea, 345. Merelrix, S45n. Pilaria, 345n. ovatus. Pilar, (345, n.). Saxidonms, 341. ovoidea, Phohdidea, 432 (twice), 433, 434-435. Pholas, 434. oroides, Ldomesus, (666). ovulata, Columbella, (680). Conella, 680. Pyrene, 680, (680). ovidoides, Pyrene, 680. ovulum, Caduhis, 438. omdus, Cadulus, (438) oimmlarerti, Cylichnella, 453n. oiveni, Peclen ( — ), 197. Pecten \ Patinopecten) , 197. Owens Lake, 74. oxia, Leda, 125. Nuculana, 125. oxybasis, Cidarina, (838). Solariella, 838. oxylata, Volvula, 450. Volvuldla, (450). oxytropis, Turris, 505. Oyster-bed facies, 28, 33, 34, 59, 105, 106, 884. Oysters, 156 ; see also Ostrea; for pearl-oysters, see Pleria. pahloensis, Chione, 319. Macoma, 372. Mactra, (392). Mulinia, 392. Nassarius (Uzita), 678. Natica (Neverita), 802. Pecten (Aeqxdpecten) , 199-200, 2U1, 230, 233. Pecttn (Chlamys), 199. Pecten (Patinopecten) , 197. Pecten (Plagioctenium.) , 199, 200. Polinices (Neverita), 802-803. Thais (Stramonita?), (716n.). Trophon, 716n. Venus (Chione), (319), 320. paceana, Strombina, 700. Pachycrommium, 807. pachyderma, Anachis ( — ), 688. Pachydesma, 340, n. pachypleura, Epitonium (Sthenorytis) , (854). Scalaria, (854). Sthenorytis, 854- Pachypoma, 817, 818, 818 (twice), 820-821. Pacific Beach, Pleistocene, 61 (table); Pliocene, see San Diego formation. padfica. Area (Navicula), 142, 143. Astrsea (Pachypoma), 820, 821. Byssoarca, 143. Calyptogena, 278, 278-279, pi. 13, figs. 13a, 136. Cytherea, 354- Dosinia, (354). Hydlina (Cystiscus ?), (628), (632). Leucosyrinx (Surc.ulina) , 510. Malletia, 132. Marginella, 628, 632. "Marginella," 628, 632. Neptunea, (653), (654), 723. Priene, 735. Ranella (Priene), 716, 735, 736. Venus, 354. pacificum, Argobuccittum, 735. Cymatium, 653. Cymatium (Linatclla), 654- pacificus, Boreotrophon, 723. Trophon (Boreotrophon), 722, 723. Trophon (Neptunea), 723. packardi, Chrysodomus, 653, 713. Neptunea ?, (653), (713). Tritonalia, (i5S), (713). packardii, Pleurotomella, 510. Pleurotomoides, (510), 511. Packard's Hill, 35. pagoda, Defrancia, 510. Pleurotoma, 510. Pleurotomoides, 510, 511. Volume I i Pliocene and Pleistocene Mollusca of California 1011 pagodus, "Pleurotoina," 510. pailoloensis, Hemipleuroloma, (571). Pseudogemmula, 571 . painei, AcU'ort (Riclaxis), 444, 930. MaHielia, 588. Mangilia, 527, 528, 5SH. pajaroanus. Schizotharus, 405-406, \>\. 22, figs. 6n, Qh, S. pajaroana, Venus, 405. pajaroensis, Schizoths^us, 405. Palxopinna, 144. paleacea, Acmsea, 812, 812. Collisella, 812. Paleontologic study, 81. Paleozoic sediments, 50. pallescens, Columhella, 68 1. Pyrene, (681). palliata, Litlorina, 781. jmlliatus. Turbo, 781. pallida, Drillia, 576. Hyalina (Neovolvaria), (029). Mactra (Mulinia), 400-402, 926, ]il. 22, figs. 7a, 7b, 7c. Marginella, 629. Pleurotoma, 576. Pijrula, 648. Solenosleira, 648. pallidus, Cantharus, (648). Clavua (Cymalosyrinx), (563, as johnsoni), 575, 576- 577, 578, 579, pi. 26, figs. 16a, 166, 17. Palliolum, 236 (twice). Pallium, 156, 170-175, 175, 183, 184; .5. s., 170, 171, 174, 175. pallium, Pecten, 170. palmaross-, Chicoreus, (728). Murex, 728. Triplex, (728). palmeri, Amphissa, 701. Cancellaria, 617. Claims (Cymalosyrinx) , 578. Cosmioconcha, (701), 702. Pecten (Aequipecten), 199, 206. palmula, Oslrea, 152. Palomas Canyon, 30, 105. Palos Verdes formation, 37, 41, 43, 45, 61 (table), 75 (table); terrace, 39, 45, 47 (diagram), 49, 64, 69 (table), 73, 74. Paludina, 68, 69 (table), 71, 75 (table). Panama, faunal province, bibliography, 100-101; connection with Caribbean, see Caribl)can and mi- gration of species; see also Gulf of California and faunal provinces. patiamense, Cardium, 305. Lsevicardium (Mexicardia), (30-5). panamensis, Bulliis, 456. panamica. Vol ulella, 450. pandionis, Pleurotomella, 510. Pleurotomoides. (510). Pandora, 220, 260-263; s. s., 260, 260. Pandoracea, 260-264. Pandorid^, 260-263. Pandorina. 264- Panomya, 423, 425-427, 427. Panopsea, 423, 424, 425, 426. Panopc, 133, 423-427; s. 6-., 423-425, 426. panope, Taranis, 573. Teres, (573). Panupea, 423 (twice), 4^4- panthea. Claims (Clathrodrilliii), 579, 580. Turricula (Surcula), 579n.. panzana, Ostrea, 154. papalis, Genota, 502. Mitra, 634. Pleurotoma, 502. Valuta, (134). Paphia, 292, 316. 324-325, 324, 325, 327, 328, 328n., 329, 330, 331. 332, 340, 341, 343, 344, 345, 351. paphia, Venwi (Chione), 324. papulosa, Fissurisepta, 85 In. Puncturella (Fissurisepta), (-1510.). Turritella, 774, 776. papillosum, Buccinum, 672. papillosus, Alectrion, 670, (672). papyracea, Anatina (RaHa), (407), (408). dementia, (333). Gari, 382. Lairignon, 407. Mactra, 408. Pholadidea, 433. Tellina, (382). Venus, 333. papyraceus, Pholas, 433. papyria, Lulraria, 409. Pteropsis. (409). Papyridea, 311. Paradione, 343. Parallele pi pedum, 144- Parallelodon, 133. parallelum, Buccinum, 668, 669n. paramegudon, Oslrea, 150. Paramelaria, 471, 680. paramoea, Turhunilla (Chemnitziii), 866. Parapholas, 435. parapodema, Venus (Chione), 320. Parasipho, 664- parasitica, Chama, 280. parcipicta, Margarita, 842. Margarites (Lirularia), 842. parcipictus, Margarites (lArularia), (842). pare'.a, Pleurotomella, 510. Pleurotomoides, (510). Parietal callus, illustrated, 796. parilis, Diplodonta, 294. Loripes, 294. LvAnna, 126. Mysia, 294. Taras, (126), 294 (twice), 294-295, 375, iil. 14, figs. 12a, 12b. pariolida, Anachis ( — ), 688. parmeleei, Pecten (Chlamys), 171. Pecten {Pallium), 171, 171, 172, 900. parte filosa, Clathurella, (605). Glyphostoma, 605. partita, Cythara (Conopleura), (603n.). Pleurotoma, 603n. 1012 San Diego Society of Natural History Mkmoirs Tparm, Anachis (—), (688), (688). ColumbeUa, 68S. Crassinella, 270ii. Gouldia. 269. Olivella. 625. Pholas iZirfsa). .',.1.'. Parvamu.'isium, 234-236. Parvilucina. 288-289, 290. parvula, Ain/iliiKsa, 701. Cosmioconcha , (701), 702. Mitrella, (696). parvulum, Buccinum, 696. pari'um, Buccinum, 688. Calliostoma, S33. pannis, Pcctcn (Pallium), 175. Pholas (Zirfs'a), (432). Pa.so Robles formation, 61 (table), 62. patagonicus, Pecten, 165. Patella, 788 (twice), 789, 791, 794, 795, 80S, 809, 810, 811, 812, 813, 847, 849, 851. Patellidx, 809. Patelloida. 812. Patinopecten, 96, 105, 1.56, ISS, 1S9, 191, 192-198, 201, 224. patvla, ArchUecUmica (Climacopoma), (785n.). Axins-a, 287. Ldttorina, 781. Lucina (Myrtea), (287). Machsera, 109, 387. Siliqim, 387-388, SS9, 389, 390, 924, of. pi. 21, fig. 9. Patulaxis, 785n. patulum, Solarium, 785 n. patulus, Pectunculus, 137, 287. Solen, 387. paucicostata, Li- ptolh i/ra, 822, 823. paucicostalum, Homalopoma, (822), (822), 822, 823. paucicostalus, Pecten (Aequipecten), 205, 206. Pecten (Plagioctcnium), 206. Turbo, 822. paucivaricala, Miiricidea (PlnjUoiiolus), 706. Purpura, (706). paulina, Astaric, 26Sn. paupercula, Bulla, 457. Bullaria, 457. pauperculus, Bullun, (457). pavlova, Lora, 524. pavonina, Strombina, 700. paytensis, Pyrene, 681, 682, 684. pazi, "Murex," 725n. paziana, Cymalosyrinx, 576. pazianiis, Clavus (Cymato.yyriiLf), (576), 577. Paziella, 725n. pealii, Pecten, 162. Peat, 68, 69 (table), 74. peckkami, Pecten (Pseudamusium) , 237. Pecten (Pseudamussium), 236. pecora, Turbonilla (Strioturbonilla), 868. Pecten, 51, 52. 55, 60, 95, 164-238; s. .s., 164-170, 170, 171, 175, 195. 200, 202, 218, 220- 229, 902. Pecten coalingensis zone, 34, 52, 61 (tul)le), 420. pecten, Murex, 704- Pectinacea, 154-239. pcctinala, Cusjridaria (Cardiomya), 265, pi. 1, fig.s. Ifi, 17. Neara, 265. Pectinella, 235. Pectinida', 8, 13, 154-238. pectunculoides, Venerupis (Protothaca) , (329). Vemts, 329. Pectuncuhis, 133, 133, 134, 135, 136, 137, 276n., 287, 30.9n., 423. pcdroana, Alvania, 767. Callista, 334. dementia (Compsomyax), (334). Cyathodonta, 259. Cypr'cardia, 357. Lacuna, (782). Littorina, 782. Macoma, 361. Mangelia (Beta), (592). Mangilia, 592. Margarita, 842. Margarites (Ldrularia), 842. Mitrella, (693), (694). Nassa, 693, 694. Neptunea, 723. Odoslomia (Irii/clla). 873. Olivella, 408, 626-627, (i27, pi. 24, fig. 10. Petricola, 355, (357). Plagiostoma, 236. Pleurotoma (Leucosyrinx), 556. Spirotropis (Anliplanes), 556-657, pi. 26, figs. 24, 32. Strephona, 626. Tellina, 361. Terebra (Slriokribrum), 467, 469-470, 933, pi. 24, fig.s. 18, 24. Thracia (C yaihodonla) , (259), 259. Trifora, 766. Triphirrn, 766. Trophon (Boreolrophon), 723. Turbonilla (Pyrgolampros), 869. pedroanum, Strioterebrum , 469. pedroanus, Margarites (Ldrularia), 842. Myiilus, 244. Pecten (Pseudamusium) , 237. Pecten (Pseudamussium) , 236-238. Triphoris, 766. Trophon (Boreolrophon), 723, 723. pedro'cnse, Micranellum, 780. pedroeiisis, Acteocina, 447, 44S. Relusa (Acteocina), (447), 448. Pegophysema, 292. Pclecypodu, 109-435. pelex, Cranopsis, 851n. Puncturella (Cranopsis), (851n.). pell a, Area, 119n. Nuculana (Lembulus), (119n.). pellis-serpentis, Tegula, (825). Trochus, 825. pellucida, Anaiina, 406. Chama, 44, 279, 280, 281. Erycina, 299. Hyalina, 629 (three times). Trigona, 622. Vermicularia, (776), (776). pellucidus, Vermetus, 776. Volume I ] Pliocene and Pleistocene Mollusca of California 1013 pelta, Arm:m, 810. Acmxa (Colliisella), SIO. peltoides, Nacella, ^63. Siijhonaiio, J,63. Williamki, 403, 463-464. penderi, Leda, 124. Nuculana, 123, 124. penelope, Cytharella {Agatluiloinci). 001. Mangelia (Agalholoma), (601). penicillata, Anachis (Chauvetia), 687, 687, 689. Climiella f, 566. Columbella, 687. Drillia, 558, 560, 566. Pleurotorna, 566. PKimhmwUdoma, .544, 5.52, (.5,58), .559 (twice), 560- 562, 562 (three time.s), 563 (three times), 564 (four times), {566}, p\. 26, figs, an, .56, IS. Penion, 642. penita, Leda, 12^. Neilo, 124. Nucula, 124. Nuculana,, 124. Penilella, 4S4. Pholadidea, 4.33, 434, pi. 24, fig.s. \n, lb. Pholaduka (Pi-inldla), 434. Pholas, 434. Penilella, 433, 434, 434. pennatum, Slephopoina, 777. pennatus, Alel s, 777, pi. 24, fig. 5. Pennines, 68. pensylvanica, Lucina, 283, (284). Venus, 283, 284. penlalopha, Turbonilla (Lancea), S72. Turbonilla (Mormula), 872. penlegoniosloma, Gadinia, 462. Mouretia, 462. Peplitm, 174-175, 236. ptramahilis, Soliirullo, 839. perangulaia, Eupleura, 714. perangulalus, Murex, 714. peranligua, Cardila, 277, (278). Peratotoma, 609. peraUeiiuala , Mag-ilia, 5,91. Mangel id {Beta). 591-592. Mangilid, 5!fl. percarus, Pccten (Aequipeclen), 208, 210. perdix, Buccinum, 741. Tonna, (741). perelegans, Trophon (Boreolrophmi /), 723. perfalcata, MelaneUa, 862. Melanella {Balds), 862. perforans, Venerupi/s, (325). Venus, 325. pergracilis, Amplii.'i.'ia, 701. Cosmioconehn, (701), 702. Exilia, 665n. pericochlion, Chrysodomus, 659n. Neptun a lSulrn.fipho), 658, 659, 660. Periploma, 255-256. Periplonmlidie, 255-256, 256. perita, Muricidea, 712. Ocinebra, 712. Trilonalia, 712. p( ritiLs, Murex (Ocinebra), 712. perlabiata, Area, 141. Perhnmdir, 14i . perlaminosa, Veiierupis {Humilaria), 326-327, 335. Venus, 326. permacra, Cyclas, 287. Lucina (Myrtea), (287). pernodata, Cryptogemma, 511. pernodatus, Pleurolomoides, 511. pernodosus, Pecten (Lyropecten) , 179, 1S2. pernula, Area, 119. Lseda, 119. Leda. 119. Nuculana. 119, 120 (twice). Peronidia, 362-363. Perolyphis, 72.5ii. pcrparvula, Dicaricella, 297. perpinguis, Aleclrion (Schizopyga), 673. Nassa, 673, 676. Nassarius (Schizopyga) or Nossarius (Tritia), 672, 673 (twice), 673-674, 674, (676), pi. 26, figs. 51, 52. perpotulcrosa, Purpura, 705. perrini, Cancellaria, 616, 617, pi. 27, fig. 8. Myiilus (Mytiloconcha ?), 246. Pecten (Lyropecten), 190. Pecten (Verli pecten), 188, 190, 191. Sinum, 807. Solen, 386, 386. Spondylus, 160. Ferris pene]ilaiii, 44, 62. Perrisonata, 119. perron, Murex, 611. Perrona, (611), 611. Perrona, (480, as Pusionella). 481 (diagram), 483, 484, 559 (twice), 567, 575, 611-612, 934. perronii, Perrona, (611). Pleurotorna, 611. Persicula, 629, 629. persicula, Persicula. (629). Vohda, 629. persimiUs, Leucosyrinx (Aforia), 508. persona, Acms-a, 811. perspectiva, Archileclonica, (785). perspectivum. Solarium, (785). perspectivus, Trochus, 785. pertenuis, dementia (Egesta), (323), 327, 335, 406. Reiusa, 445. Venus, 323, 335. Venus (Chione), 335. pertumida, Turrilella, 775. peruviana, Anomia. 240, 242, pi. 12, figs. 2, 5. Pteria, 148. perversa, Antiplanes, 553, 554. Crassispira, 553. Drillia, 5.53. Pleurotorna, 552, 553, 556. Spirotropis (Antiplanes), 35, (552), 553, 553-557, 558 (twice), pi. 26, figs. 22, 23';, 23"). s. .s., 553-555. Surcula, 552, 553. Turris, 5.53. 1014 San Diego Society of Natural History Memoirs ■pesfelis, Ostrca. 17 1. Pecten (Pnlliitiii). 170, 171. PetaloconcliU!<, 778. pelholaius, Tvrho, 815. petitii, Paphin, 330. Terebra (Strinterchrum), J,68. Venerupis (Protolhaca) , 329, n., {330), 331. petraris, Anachis (Chauveiia), 687n. Pelrasma, 109. Petricola, 279, 332, 332, 354-357. petricola, Dcidnlium, 437. Litloritiu. 781. Petricolarin, 356-357. Petricolida, 3.n4-3r)7. Petrophila. 462-464. Pctropoma, 821. pelrosa, Bulla, 454, 468, 460. Bullina, 454- Cylichna, 454. Cylichnella. 454- Haminen, 460. Haminoca, 454, (458), 460. pfeifferi, Oilnrodnma, 831. Omphalius. 831. Trochus, 831. "Trochits," 831. Phacoides, 283, 28 ', (twice). Phsenospira, 628. phsethusa, Cyihardla, 601. Mangelia (Agaihntnma), ((iOl). Phalium, 739n. phanea, Anachis ( — ), 689. Odostomia (Evalea), 875, 876, pi. 24, fig. 25. Phasianella, 813, 814, 815, 815. Phasianellida., 813-815, 815. Phialopectcn, ISO, 189n. philberti, Pkilbcriia, {609). Pleurotoma, 609. Raphiloma, (609). Philbertia, (see Raphiioma), 591, GOO (twice), 601, 606n., 607, 60S (three times), 609. pkilippiana, Terebra ( — ), 469. Terebra (Slriolerebrum) , 4S9. philippianum, Strioterebrum, 469. philippinensis, Pleurotoma, 609. Psewlodaphnella, {609). Raphitoma. (609). Philobrya, 148-149. Philobryidif. 148-149. philodicc, Clathurella, {607). Mangilia, 607, n. Phlyctidenun, 294. Phoeben, OS. Pholad l)orings, 38, 64, 331, 332. Pholadacca, 429-435. Pholadidse, 8, 333, 429-435. Pholadins; 4.30-433. Plioladidsa, 433. Pholadidca, 433-435, 930. phnladiforiiiis, Pclricolci, 356, 356. pholadis, Mytilis, 428. Saricava, 428, 429. Pholadomyn, 424, 425. Phola.% 430-433, 930; s, s., 430-431, 431. Pholids'a, 433. Phorcus, 831. Phos, 610, n. Phragmnpholas, 430. phrync, Cytharella {Agathotoma), 601. Mangelia {Agnthotoma), (601). phylira, Mangelia {Beta), {591). Philbertia {N annodiella) , 591. Phyllnnnl}is,706, 715, 72S, 729 (three times). 730, 731 (twice), 731. Phylogeny, 13, 85, 90, 93, 155, 157, 158, 161, 162, 168, 178, 198, 230, 316n., 340, 343, 351, 354, 478, 480, 481 (diagram), 48.3-484, 487, 492, 492-493, 504, 5.59, 611, 756n., etc. Phylum, term applied to a clan or groiip of closely- related species within a genus, for which division the writers would prefer to substitute the term "group," 775n.; not to be confused with phylum as applied to one of the major divisions of the animal or vegetable kingdoms; see group. Phymorhynchus, 508, 509, 509. Physiography (see also terraces and old land surfaces), 46, 49, .54, 77. jriea, Diodora, {850). Fissurella, 850. jiieala, Columbella, 680 (twice). Pyrcne, (680, twice). Pico, Canyon, 29, 30, 32, 35, 103, 104, 105; formation, 31 (diagram), 32-36, 40, 52, 60, 61 (table), 69 (table), 70, 102-104, 105, 106; town, shown on sketch map, 27. picoe?isis, Pecten, 163. Pecten {Chlamys), 163. pieta, Columbella, 680. Pyrene, {680). Turris, 505. pictinn, Calliostoma, 833, 834- piercei, Bathytoma, 488. Pleurotoma, 488. Tvrricula, 487, 488, 488, 547. pilearc, Murex, 732n. Triton, {732n.). pilearis, Cabestana {Septa), (732n.). Pillar Point, .55. Pilsbry, H. E., 9. Pinctada, 147-148. pingelii. Beta, 529. Dcfrancia, 529. Lorn, (512), 529, 529, 530 (twice). Oenopota, 512. pinguis, Cinulia, 44^- Marcia, (325). Tornatells'a, (442). Ve7ius, 325. Pinna, 144-147, 148, 149; s. s., 144-146. VOLIME I 1 Pliocene and Pleistocene Mollusca of California 1015 'pimm, Concha, IJfO- ■pinnaius, "Typhis," 725n. Pinnids-, 144-147, 149. piona, Antiplanes, 556. Pleurotoma, 556. Spirotropis {Antiplanes), (556), 556. Pirula, 7J,2. Pisania, 646, 647, 685 or 6S5. pisnm, Divaricella, (297). LuciTia (—), 290, 297. Lucina (Hellucina), 290. Luciria (Dimrictila), (297). Pilar, 222, 316, 334, 343, 344-348, 348, 3.51, 3.54, 916; s. s., 344-346, 346. Pilana, SU, 345, n., 346, 349, 3.50. pillieri, Peclen (Lyropecten), 179. pilysa, Lora, 523. placenla, Aslarle, 267. Placupeden, 192. Placuuanomia, 240, 241, 241, 242, 242-243. Placunomia, 242. Plagiocteniiim. S9, 1S4, 1S6, 187, 198, 199, 199, 200, 202, 206, 206-220. Plagiosl07>m, 159, 236. Plaisancien, 69 (table), 70. Plaits, see plications. Planaxis, 672n. planaxis, lAtlorina, 781. planicosta, Cardila, 276. Venericardia, 94, 95, 276. planicoslalum, Cardium, 312, 312. Fragum, (312). planicoslum, Sigarelus, 80 J. Sinnm, 806. planilirala, Haliotis, 846. plaiiiliraliis, Coniix, 475, 475. planiuscula, Macoma, 372, ]j1. 14, figs. 11a, 116, pi. 20, figs. 8a, ^h. Periploma, 255-256, pi. 13, figs, la, 16. planospira, Cancellaria, 613, pi. 27, fig. 4. plamdala, Maclra (^•>pi.sula}, (S92), (395), 397, 397-398. Spisula (Hemimaclra), 397. Spisula (Maclromeris), 397. Spisula (Symnwrphomaclra), 392, 396, 397. StandeUa, 395, 397. Plalyodun, 415-416. Platyschides, 438. Pleclaria, 689. Pleclosolen, 109. plectrum, Buccinum, 668. pleimegona, Odostomia (Evalea), 875. pleislocena, Rissaina, 769. Pleistocene diastrophism, see diastrophic revolution of the middle Pleistocene. plena, Ldttoriim, 782. Yoldia, 131, 131. Pleurofusia, 481 (diagram), 487, 489-490, 494, 665n. Pleuroliria, 504. pleuronecles, Amusium, 231. Ostrea, 230, 231. Pecten (Amu.iium), 95, (230), 231, 231, 232. Pkurotiima, 482, 483, n., 484, 485, 486, 487, .',88, 489, 490, n., 494, 4.95, 49611., 497, 498, 499. 500, 501, 503, 50411., 505, 506, 508, 509, 510, 512, 514, 515, 516, 518, 521, 522, 524, 525n., 531, 533, 534, 535, 536, 338, 540, 542, 54411., 545, 546, 548, 549, .5.50, 551, 552, 3.53, 554, 555, 556, 560, .561, 564, 366, 569, 570, 571, 573, 574, 575, 576, 577, 578n., 579, 580, 581, n., 583, 584, 585, n., 587, 589, 595, .596, 60311., 6O4, 605, 608, 609, 610n., 611, 623, 686, 937, 938; see Turris. pleurotomaria, Bela, 528. Lora, (512), 528, 528. Oenopota, 512. Pleurotoma, 512. pleurotomarias, Fusus, 512, 528. Pleurotomella, .504, 506, 507, 508 (twice), 509, 510 (twice), 511, 511, 513, 548, 549, 610. Pleurotoinidx , 4'77. Pleurotomina, 512, 513. Pleurotomina, 512, 513. Pleurotomoides. 481 (diagram), 483, 504, 507, 510, 510- 511, 513 (twice), 5;2, 547, (548 — evadne), .570, 571 (twice), 585, 603, 608, 610 (four times). plica, Ostrea, 170. plicata. Area (Acar), 144- Area (Barbatia), 143. Eupleura, (714). Ranella, 714- Retusa, 445. Thais (Nucella), (716), 717. Thracia (C yathodonla) , 259. plicatella, Anatina (Ra'ela), 96, (407), 407-409, 928 Clathurella, 577. Cymatosyrinx, 577. Laboisa (Raeta), 4O8. Lutraria, 407 (twice). plicatellus, Clavus (Cymalosyrinx), (577), 578. Plications or plaits on the columella, (483), 543-546, .573, 596, 612, 622, 623, 628, 631, 633, 634, 636, 637, 682, 683, 695, 933, etc. plicatum, Buccinum, 716. "Buccinum," 716. plicatus, Pecten (Pallium), 170. plicifera, Bela, 524. Lora, (524), (537). Mangilia, 537. Plicifusus, 664, 664, 665. plicus, Pecten (Pallium), 170. plumbea, Pseudolwa, 649n. plumbeum, Buccinum, 649n. plumula, Lithodomus, 253. Lithophaga, 253, 253. Lilhophagus, 253. Pododesmus, 240, 241-242, 243. Poederlien, 69 (table). Poiriiria, 707, 725n. polare, Buccinum, 668, 669. Polinices, 799-805: s. s., 799-800. polilum, Dentalium, 437. politus, Cadulus, 438n. 1016 San Diego Society of Natural History Memoirs Pollia, 646. polycaste, Cnjploqcmma, 5J,S. SpirotropiK, 507, 548. Polymetis, 363. Pohjnices, 7.99, 800, 802, 804, S05. lolynotata, Borsonella, 567. MnnUiopsis, (567). polyrujma, Madra (Spisula), 97, 394, 394-395, 397, 399. Spisula (Mactromeris), 394. Polyplacophnra, 878. Polyplex. 717. Polyschides, 438. Polystira, 504. Polylropa, 717. pomata, Peclen (Aequipecten) , (218). Pecteii (Phigioctcnium), 218. Pomaulax, 817-820, S20. ponium, Chicorcus (Phylloii.oliis), (730). Murex, 730. ponderosa, Artcmi.'<, 351. Dosinia, 34, 351, 351-354, pi. 15, fig.s. la, lb, Ic; s. s., 361-352. 3.53. Dosinia (Dosinidia), 352. Forrerii, (716), 727. Haliotis, 845. Madra (—), 394. Mactra (Spisula), 394 (twice). Thais (Stmmonita ?), 715, 716, n., (721), 727, 729. ponderosum. Trophon, 716n., 721. Trophon (Forrcria), 727. ponderosus, Trophon, 727. pontonia, Leda, V2l. Nuculana, (121). popofianus, Sa.vidomus, 342. popoi'ia, Lora, 519, 525, 532, 594. porceUa, Corbida (Lcntidium), 422. Porcellana, 628. Poromyacea. 265-266. Por pteron, 725n. Porphyria, 624- porrecta. Lacuna, 783. porterensis, Peclen (Chlamys), 191. Peclen (Verlipeclen), 191. porleri, Olirella, 627. Porllandia, 122, 127. porllandica, Nucula, 127. Yoldia, (127). porlolaensis, Chrysodomus, 6Jf5 (twirc). Fusus (Buccinofusus) , 645. Kelletia (Searlesia), (645), 645-646. posoensis, Kelletia, 644. Siphonalia, 644- Post-glacial, climatic zones, 68, 74; erosion, 75 (table), 76n. (on 77); length of, 75 (table), 76, 76n. (on 77); miscellaneous events, 69 (table), 73, 74. postplanata, Neplunea (Sukosipho ?), 658, 669. postplanatus, Chrysodomus, 659. Potamides, 758. Potamis, 763. poulsoni, Hinnita, 160. Murex, 712. Ocinebra, 712. poll I. son/ — ronli lined. Peclen, (160), 160. Trilonalia, 642, 712, pi. 32, fig. 10. Poway terrace, 46, 47 (diagram), 48, 55, 56, 60, 62. prsecedens, Arcualomitrella, (689), 692, n. Columhella, 689, 692, n. Mitrella, (689), (692, n.). prspcisa, Mya, 414- prsecursor, Anachis, 685-686. Columhella, 685. Leda, 122. Nuculana, 122. "PyramideMa," 864n. Trophon (Boreolrophon) , 723, 723. prffnominata, "Chrysodomus," 653, 713, 714- Trilonalia, (653), (713), (714). prarupla, Crepidula, 791. jrratenuis, Cochlodesma, (255n). Mya. 255n. pra'imlidMS, Peclen (Aequipeclen) , 206, 206. Peclen (Leplopeclen), 206. Pragrnopholas, 430. precursor, Aslrsea (Lilhopoma), (820). Aslrsea (Pachypoma) , 820, 821. Aslralium (Lilhopoma), 820. Madra (Spisula), (395), (396). Spisida (Hemimaclra), 395, 396. Thais (Nucella), 718. prelamellifer, Irus, 332-333, 918, pi. 18, fig. 7. Pressler, K. D., fainuil list not incorporated, 98. pretiosa, Scalaria, 852. preliosum, Denlalium, 437. Epitonium, (852). pretiosus, Peclen (Lyro peclen), 185. prevosliana, Psephsa, 21, 96, 459, 633-634, 942, pi. 27, fig. 9. Volula, 633. prihiloffensis, Chrysodoniu.'i, 656. Neplunea, 667. jyrivilova. Lorn. 520. Prienc, 735-739. prima, Borsonia, 543 (twice.) princeps, Chicoreus (Phyllonolus) , 730. Conus, 476. Crepidula, 20, 44, 789-790, 791. Fasciolaria , 637. Murex (Phi/Uonotus), 730. Prionodesma ea, 109-254. Priscofusus, 481 (diagram), 487, 490, 490-492, 665n. Prismatic sh.ll layers, 154, 260, (266?); see also Ino- ceramus. prismatica, Oslrea, 150. proaims, Peclen, 158, 161. procerum, Cardium, 305. Cardium (Ringicardium), 305. Ls-vicardium (Meiicardia), (305), 305, 313. producta, Phasianella, 8I4. Tricolia, 8I4. profirua, Semele, (375). TeUina, 375. Profile of equilil>riuni, 24, 26, 32, 43, 47 (diagram), 48, 49. profundior, Mya, 411,414, (415). Volume I Pliocene and Pleistocene Mollusca of California 1017 Progabbia, 6I4, 615, 618, 619, 620. prolotigata, Cardiia (Miodontiscus), (275), 276. Vdutina, 808. V eiiericardia (Miodon), 276. Venericardia (Miodontisais), 276. prolongatus, Miodon, 275. Promartijnia, 831. propalulm, Peclen (Palinopecten), 192-193, 194, 195, 195, 196, 196, 197, pi. 22, fig. 5. Propeamusium, 232, 234- Propeamuss-ium. 156, 232-236, 232, 235, 2.37, 23S, 902: s. s., 232-234. Propebela, 512. ■proteus, Pecteii, ( — ), 214. Peclen (Aequipecten) , 214- protexta, Donax, 109. Leda, (119n.), 124. Nuculana (Perriscna'a), (119n.), (124). Perrisonata, 119. Plectosolen, 109. Solen (Hypogella), 109. Solena, 109. Terebra (Striolerehrum), 470, 470. prolexlum, Cerithium, 4'70n. Protocardia, 311, 311, 314-315. Protocardium, 314- Protoconehs or nuclei, used in classifieation, variation in, etc., 93, 479-480, 490, 591, 605. Protoplax, 430. Protoaurcula, 487. Prolothaca, 327, 327, 328-331. Provinee.s, see faunal provinces. proximo, Macoma, 369. Semele, (376). Tellina, 369. proxiinum, Amphidesma, 376. Prunum, 628. prunum, Margiuella (Prunum), 628. Psmnmobia, 371, 3S1, 382, 383. Psammosolen, 387. Psammolea, 365. Psepha^a, 96, 222, 633-634. Psephidia, 336-338, 338. Psephis, 336, 338, 356. Psevdamusium, 234, 235, 237, 238. pseyda7nusium, Peclen (Pseudamussium), 235, 236. Pseudamussium, 156, 158, 233, 234, 235-238, 902. pseudamussiutn, Pecten (Pallium), (235). Peclen (Pseudamussiujn), 235, 236. Pseudocardium. 400. 402-404. Pseudochama. 280-281. Pseudodaphnella, 609. pseudo-fossile, Cardium, 309. Lsnncardium (Cerasloderma), (309). Pseudogemmula, 571. pseudohexagonum, Dentaliu/n, 436. pseudolateral, 316, 317. PseudoUva, 649, 650, 727. pseudo-Iunule, 284, (284), 285, 286, 291, 295. Pseudomalaxis, 785, n. Pseudomallelia, 132. Psevdomarginella, 628. Pseudomelaloma, 481 (diagram), 483, 543, 544 (three times), 546, .547, 5.52, .5.53, 557, .558 (twice), 558-564, .565 (three times), 574, 575, 577, 578 (twice), 938. .s. s., 658-563. Pseudomonotis, 147. Pseudoraphitoma, 586, 601, 601. Pseudotoma, 4S1 (diagram), 492, 493, 494, 494, 495, 495, 497, 49s, 500-501, 501, 502. Pseudotoxoglossa , 479, 482. Ple7ioglos.-:a. 852-861. Pteria, 147-148, 248n.; . ., 147, 148. Pleriac^a, 144-149 Ptenida; 147-148, 1.54. Pterochelus, 725n. Pteronotus, 708. Pteropoda, 440-441. Pteropsis, 409. Pteropurpura, 725n. Plerorhytis, 705, 706. Pterorytis, 709. Plerygia, 602. Ptychoslylis, 837. pubescens, Cardium, 310. La^ficardiuin (Cerasloderma), (310). Thracia, 257. pudica, Drillia, 582. pudicus, Clavus (Cymatosyrinx), 582. Puente Hills, 39, 61 (table). pugelensis, Pecten, 168. Pecten (Chlamys), 168. pugilis, Strombus, 755 (three times). pulcella, Tegula (Chlorostoma), 831. pidcherriina, Strombina, 700. pulchra, Semele, 377, 377. pulchrior, Aimchis (Chauvelia), 687, 6S9. Columbella, 687n. Mangelia (Bela), (590). Mangilia, 590. pulchrum, Amphidesma, 377. Pullaslra, 325. pullastra. Venerupis, 325. I'pnws, 325. pullala, Cerilhidea, (763). pidlalus, Potamis, 763. pulligo, ProTnarlynia, 831n. pulloidea, Tricolia, 814- pulloides, Phasianella, 814- Tricolia, 814, 814, 815. pullus, Tricolia, (813). Turbo, 813. Pulmonata, 461-464. punctata, Clidiophora, 232. Clidophora, 262. Codakia, (283). Columbella, 696. Pandora, 262-263, p'. 13, figs. 2a, 26. Pandora (Heteroclidus), 282. Pyrene, (680), (696 ?). Venus, 283. punclatoslriala, Donax, 381. punctaloslriatus, Donax, 381), 381, 381. 1018 San Diego Society of Natural History [ Memoirs piincltilNni. Buccitnitu, 6SIK pimciiculntus, Conus, 473, 474. punctoca'lata, TornaleUa, 443 (twice). jnmctocs^latiis, Acteon [Riclaxis], 443, (443), 443-444. punctocodata, Acteon (Riclaxis), 443- Rhextaxis, 443- Rictaxis, 443. pimciocoelaiim, Acteon (Riclaxis), 443- punctiilatn , Aconlhina, 720, 720. Acanthinn (Acanlhinucella), 720. Bulla, 456. Bvllaria, 4-'>6. punctvlatus, liiilliix, 456, 4.50. Pxmcturdla, 851-852. punicea, Tellina, 360, 360. pupiformis, Odoslomin (Amniiiri), S7G. Pnpillaria. 839-840. pupillus, Margarita, S40. Margaritcs (Pupillaria), (839), 840, 841 (twice). Trochus, 839, S40. pupoidca, Fcnella, 825. pupoides, "Fcnella," 825. pupoideus, Halistyliis, 825. Purisima formation, 54, 5.5, 57, 59, 60, 61 (table). purisimaensis, Chrysodomus, 662. Neptunea (Colus), 662. Pecten (Patinopecten), 21, 55, 193, 194, 194, pi. 6, fig. 3. Purpura, 649, 704, 706-708. 710, 715-718, 720, 725n.: for Purpura Laiiiarck, see Thais; s. s., 705-706, 7(^?. purpurasccns, Conus, 474. purpurata, Olira, 625. Olivella, {625). purpuratus, Pecten (Aequipecten), 30, 34, 46, 86, 206, 207, 207-212, 212, 213, 215, 219, 890, 896, pi. 4, figs. 2a, 2b, 2c; s. s., 207, 208, 209, 209, 212. Pecten (Plagioctcniuni), 207. purpurea, Alrania, 768. Mya, 427. Philbertia, (609). Pleurotoma, 609. Raphitoma, (609, twice), 609. Saxicava, 427. Purpurellus, 708, 725n. purpureum, Homalopoma, (822). purpureus, Murex 609. Turbo, 822. "Turbo," 822. purpuriformis, Caneellaria, 613. pusilla, Beta, 540. Lora, (540). Pusio, 648. pusio, Buccinum, 611. Fusus, 611. Murex, 611, 646. Perrona, (611). Pisania, (646). Pusionella, 480, 611, 611, 934. Pusiosloma, 680. pvstutata, Cypraa, 753. Pscudomelaioma, 559. Triiyia, 753. pygmaa, Anaehis ( — ), 689. pyramidale, Buccinum, 528. pyramidalis. Beta, 528. Lora, 525 (twice), 528-529, 529 (twice), .530 (twice), 593, pi. 32, figs. 36, 37, .38. Pyramidea, 823. Pyramidella, 864n., 865. Pyramidellidse, 865-877. Pyrene, 602, 635, 679, 680, 680-£84, 684; s. s., 680-682, 6S3 (three times). Pyrenidu, 8, 13, 471, 581, 600, 679-704. Pyrgisculus, 872. Pyrgiscus, 870-871. Pyrgolampros, 868-870. pyriformis, Cypricolina, 632. Ficus, 742. Hyalina (CyprseoKna), (632), 632-633. Marginella, 632. Merovia, 632. Tegula (Chlorostoma), (827). Trochus (Monodonta), 827. Volutella, 632 (twice). Pyrolofusus, 652. pyrrhula, Cytharclla (Agalholoma) , 601. Mangelia (Agathntoma), (601). Pyrula, 646, 648, 726, 741, 742, n., 743, 746. Pyrulofusus, 652. Q quadra, Lora, 525, 532-533. rjuadragenarium, Cardium, 306. Lavicardium (Trachycardium) , 306-307, )il. 19, fig. 15. quadrana, Macoma, 372. quadrata, Caneellaria, 618, 618. Cryptomya, 417. quadriceps, Architeclonica, (785), 785, (786), 786. Solarium, 785, 786. quadricincta, Asthenotoma (Endiatoma) , 568. Moniliopsis (Endiatoma), (568). quadrifilatum, Bittium (Semibittium) , 762. quadrigenarium, Cardium, 306, 307. quadrillum, Mangelia (Mitromorpha ?), 599. quMdriscriata, Cytharclla, 601. Mangelia (Agalholoma), (601). quadrisulcala, Cyclas, 295. Divaricella, (295), 296, 297 (twice). Lucina, 296. quentinensis, Agalhotoma, 587. Cryptogemma, 570. Cytharclla, 587. Mangelia, (587, twice.). Moniliop.ns, 570, 571. Semele, 377. Thracia, 258. quillayutensis, Aporrhais (Arrhoges), 705. Purpura, (705). quinquecincta, Moniliopsis, 568, \A. 26, fig. 33. VoLUlIE I ] Pliocene and Pleistocene Mollusca of California 1019 quoyana, Bullaria, 457. guorjanns, Bullus, 457. quoyi, Bulla, 4^7. Bullus, (457). quoyii, Bulla, 457. Bullus, (457), (457). Quoyula, 646. R radians, Calyptra'a, 795. Calyptrxa (Infundibulum) , 79-5. Calyptnea (Trochita), (79.5), 950. CyprcPa, 7-53. Lucina (Myrtea), 285. Trivia, 753. Trochus, 795. radiaia, Amiantis, (350). Oadinia, (462). Glans, 277. Rowellia, 462. Siliqxui; .386, (387). Tellina, 357. Veniis, 350. radiatus, Solen, 387. radix, Chicoreus (Muricanthus), 731. Mure.x, 731 (three times). Phyllonolus, 731. Radula, 239. radula, Peden (Pallium), 170. Radulae, used in classification, variation of, etc., 93, 478-479, 480-482, 517, 522, 584, 596, 611, etc. flof/a, 407-409. ralpki, Turhonilla (Strioturbouilla), 867, 867. ramonensis, Cancellaria, 619. Polinices, 800. ramosus, Chicoreus, (728), 728. Murex, 72S. Rancho La Brea, 45, 69 (table), 72, 73, 74, 75 (table), 76. raiidolphi, Pecien (Pseadamusium), 237. Pecten (Pseudamussiuni), (237). RaneUa, 714, 715, 731, 734-739, 734; s. s., 734-735, 735, 737. Ranellid^\ 731. Rangia, 409-410. Ranula, 734n. Ranularia, 734n. Rapa, 741. rapa, Cancellaria, 617 (twice), 617, 620. Rapana, 646. 646. Raphiloma, 481 (diagram), 483, 542, 573, 585, 586, 589, 590, 604, 605, 608-610. rapulum, Perrona, 611. rassina, Lora, 524- rastellinum, Pecten, 166. rava, Clathurella, 510, (604), 606, (610). Clavahda, 6O4, 610. Pleurotoma, 6O4. rauus, Conus, 372. Raymond, Percy E., 8. raymondi, Astrxa (Pomaulax ?), (819). Astraliwm, 819. Eulima, 864. Pecten, 200. Pecten (Aequipecten), (200), 201. Strombiformis, 864-866. Trophon (Borcotroplion), 724. reagani, Yoldia, 122. reclusa, Tellina, 359, 360, 908. Tellina (Merisca), 360. reclusiana, Natica, 800. Neverita, 800, 802n. reclusiamis, Polinices (Neverita), 408, 798 (twice), 800- 803, text figs. 13i, nh, 13-, 805; s. s., 800, 801-802, 802. recluziana, Natica, SOO, 802. Neverita, SOO, 801, 802. Polinices, 800. Polinices (Neverita), 801,803. Polynices (Neverita), 800, 802, 803. recluzianus, Polinices (Neverita), SOO. recta, Modiola, 249. Retusa (Acteocina ?), 445, (446n.?). Tornatina, 446n. Volsella. 249-251, 904. rectirostris, Chrysodonius, 665 (twice). Exilia, 665 (twice). Exilioidea, 665, 665-666, pi. 28, fig. 5. Tritonofusus (Plicifuswi), 665. rectius, Dentalium, 437-438. rectus. Modiolus, 250. recurva, Columbella, 699. Strombina, 699-700, 700, pi. 26, figs. 38, 41. recunnis, Conus, 476, 476. Red Crag, 66, 69 (table), 70. Reed, R. D., 42. reedi, Anachis ( — ), 689. reevana, Cancellaria, 613. reevei, Anachis ( — ), 689. reevi, Nassa, 675. Nassarius (Schizopyga) or Nassarius (Tritia), (675). reeviana, Area (Barbatia), 143. Byssoarca, 143. refugioensis, Pecten, 229. Pecten (Janira), (229), 229. regina, Turbonilla (Morimda), 871, 872. regius, Conus, 475, n. regularis, Coiius, 476, 476-477. Hyalina (Cystiscus), 631, 631, 632. Marginella, 631. Volutopsius, 652. regulus, Lora, 538. remondi, Littorina, 781. remondii, Metula, 495. Psevdotoma, 495. Surculites (Mega^urcula), 493, 495-497, 497, 498, 499, 501, pi. 25, figs. 5, 6, 7, 8a, 8b. renaudi, Clathrodrillia, 549. Drillia, 549, .5.50. Spirotropis (Typhlomangelia), 544, 545, 546, 547, 549, 549, 550, 551, pi. 26, fig. 29. Twrns (Drillia), 549. 1020 San Diego Society of Natural History [ Memoirs resina, Clathrodrillia, 4^4^- Clamtuh. [Knefastia), 484. Turris (Surcula), 484n. restorad-onensis, Paphia, 32Sn. Venerupin (CaUilhaca), 328. reticularis, Murex, 734- Ranella, 734 or 734. reticulata, Area (Barhatia), 143-144. Bela, 523. Byssoarca (Acar), 144- Cancellaria, (612). Ficula, 743. Ficus, (742), 742, {743). Gadinia, 462-463. Homoloma, 609. Lora, 51.5, 517, 522, 522-523, .524, 525. Mouretia, 462. Oliva, 624. Peratotoma, (609). Pelricola, (355). Planaxis, 672n. PUurotoma, 522. Ranella, (734). BaphHoma, (510), (608), (609, tw-ice), 609, (610). Rupellaria, 355. Semele, (375). Siphonaria, 4^2. Tegula (Chlorostoma), 829. Tellina, 375. Vohda, 612. reticukttum, Bittium, (759). Buccinum, 734. reticulatus, Conus, 473, 4'^4- Murex, 510, 60S, 609, 610, 759. Nassariiis (Trilia), (672n.). Pleurotomoides, (510), (608). Strombiformis, 759. Sycotypus, 742. retifera, Bornia, 301. retiporosa, Nodiseala, 855. Opalia, 855. reliporosum, Epitonium (Nodiseala), 855-856. Epitonium (Opalia). 855. Retusa, 4 5, 415-449; s. s., 445-446. RetusU^, 442, 444-450, 451. Rexilhsrux, 373-375. Rhabdiis, 43S. Rhaehiglossa, 623-731. Rhexlaxis, 443. Rhine, terraces, 67, 68, 69 (table), 73; gravels of the Rhine-Meuse"delta,[69 (table). rhines, Clathrodrillia, 566. Moniliopsis, .566, 567. Turris (Surcula), 566. Rhipidoglnxxa, 813-844. rhodope, Borsonella, 550. Spirotropis (Typhlomangelia) , 560. Rhodostoma, 461. rhombiferum, Pyreiie, 680. rhomhoidalis, Aslarte, 267. Rhombus, 471, ill. rhysomia, Transennella, (338). Venus, 338. rhyssa, Admete, 622, 623. Clalhroinangelia, 599. Mangelia (Mitromorpha), 592, 597, 599, 599-600. Mangilia (ClalhromaJigilia) , 599. rhyiidus, Peclen (Paiinopeclen) , 191. Pecien (Vertipeelen), 191. ricei, Peelen (Lyropecten) , 184, 1S5. richardi, Phorcus, (831n.). Trochus, 83 In. riehardsoni, Astarte, 267. riehthofeni, Asiyris, 693, 694, 695. Columbella (Alia), 693, 694, 695. Lucina (Here), 290, 290, 908. Mitrella, (693), 694, (695), 696. Phncoides (Here), 290. Venus (Chione), 319. Rictaxis, 443-444. Rictocyma, 266. rigida, Mangelia ( — ), 599. Vemts (Antigona), 317n. Rimula, 851, 851. rinella, 7\irbonilla (Pyrgolampros) , 870. ringens, Cardiuni, 313. Cassis, 740, 741. Dolium, 741. Malea, (740), 741. Ringicardium, 313. Ringicardium, 305, 305, 313. ripleyana, Clavatula (Knefastia), 4S4. Ri.s.s glaciation, Ris.sian, 68, 69 (table), 72, 73, 75 (table), 76n. (on 77). Riss-Wiirm interglacial, 73, 75 (table). Rissoa, 760, 768. Rissoida?, 767-768. Rissoina, 585, 760, 768-769. Rissoinidx, 768-769. rilieri. Trivia, 44, 754. riversi, Colus (Latisipho), 663. Neptunea (Coiu^), 663. Pecien (Propeamusium), 234. Pecten (Propeamussiu7n), (234), 234. Strombiformis, 864. Tritonofusus, 663. riversiana, Pleuroloma (Genota), 497. riversianus, Surculiles (Megasurcula), 496, 497. Rixdorf, 68, 69 (table). robusta, Cingula, 767, 767. Terebra, 465, 465. Turritella, 775, 775. robuslus, Fv^inus, (640). Fusus, 640. "Fums," 640. Rochefortia, 301. Rochia, 823. rodeoensis, Ficus (Trophosycon), 750, 751. rollandi, Astarte, 268, 268. Rollu^, 471. roperi, Fusinus, 64^. Fu^m, 642 (twice), 643. Kellelia, (642), (643). Volume I ] Pliocene and Pleistocene Mollusca of California 1021 rojifii — mnliii lied. Mangelia (Bela), 527, 595-596. Mangilia (KuHziella) , ■'>H-'i. Roperia, 6J^, 712. Tritonalia, {712). Roperia, 642 (twice), 712. rosacea, Aslyris, (689). Columbellu, 689, 691. MitreHa, 514, (689), 691, text. fig. 7, (691, twice). rosaceum, Bucrinum, 691. rosacevs, Solen, 386, 386. rosaria. Triplex, 728. rosarius, Chicoreus, (728). rosea, Bela, 518. Corhula (—), 421, 422n. Corbula (Lentidium), 421, 4^~- Lara, 517, 518, 518, 519, 522, 526, 9.55. Pleurotoma, 5 IS. roseum, Tritoneum, 518. rossiana, Nuculana, (119n.). rossianu,^, Lembulus, 119n. Rostellaria, 634- rostrata. Area, 118, 119. Leda, (118), 119. Nuculana, (118), 118, (119). Pandora, 260. Volvula, 450. VolvuleUa, (450). rostratus, Fusinm (638). Fusus, 638. roslriformis, Crepidula, 791. rotelliformis, Norrisia, (824). Turbo, 824. rotula, Antiplanes, 554. Crassispira, 553. Spirotropis (Antiplaties) , (553), (554), 555. rotundata, Chironia, (300). Diplodonta, 293. Kellia, 300. Macoma, 373. Tellina, 293, 373. Paphia, (324). Venus, 324, 324. rolundatum, Cardium, 305. Lsevicardium (Mexicardia), (305). rotundalus, Taras, 293. RouauUia, .504, 505, .506. rouauUii, Borsonia (Cordieria), (544n.). Cordieria, 544n. Rowellia, 462. rubecula, Cabeslana (Septa), (732n.). Murex, 732n. Septa, (732n.). rubescens, Tellina, 360. Tellina (Angulus), 360. Tellina (Eurylellina), 360. ruUda, Clathurella, (604), 605. Clavatu'a, 6O4. Ldenardia, (604). Pleurotoma, 6O4. rubidus, Pccten, 162, 163. rubra, Barlccin, 784. Kellia, 301, 302. ri/hra — continued. Lasaea, 301, 302. Velutina, 808. rubrilineata, Phasianella, 815. Tricolia, (815). rubropicla, Semele, 376, 376. rubro-radiata, Gari, (382). Psammohia, 382. Sanguinolaria, 382. rubrum, Cardium, 301, 302. rude, Argobncciiium , 735. Pleurotoma, 6O4. "Pleurotoma," 604. ruderata, Chione, 331. Paphia, 331. Venerupis (Protolhaca) , 331, .332, 354, pi. 18, fig.s. .3a, 35. Venus, 331. rudis, Acmsea, 812. Clathromangelia, (604). Clathurella, (604). Pinna, 144, 145. Placunanomia, 241- Pleurotoma, (604). "Pleurotoma," (604). Pododesmus, (241). Ranella (Priene), (735). Terebra (Strioterebrum), 468. rufa, "Bela," 589. Cassis, (739). rufescens, Haliotis, 845-846. rufotincla, Anachis ( — ), 689. rufum, Buccinum, 739. rugata, Clava, 758. rugatum, Bittium (Semibittium), 762, pi. 24, fig. 8. rugifera, Opalia, 854. rugiferum, Epitonium (Opalia), 854. ruginodosa, Ficus (Trophosycon , 745 (twice), 746-748, 749 (tliicc tiiiios), 750 (three times), 751, pi. 29, figs. 2a, 26, pi. 30, figs. 5, lOo, 106. rugitecla, Crassispira, 582n. Turns, 582n. rugitectus, Clavus (Crassispira), 582. rugosa, Anachis, (684), 689. Columbella, 684- Crepidula, 790, 791. Saxicava, (427, n.), 428 (twice), 428-429. Thais (Nucella), (717). Venus (Antigona), 317n. rugosus, Donax, 378. FuHnus, (639). Fusus, 639. "Fusus," 639. Mytilus, 427, n., 428, 429. Polyplex, 717. rugulata, Bela, 515, 516, 518. Lora, (515), 516, 517, (518), 519 (three times). rugulatus, Pleurotoma, 515. rugu'Msa, Anachis ( — ), 689. Metaxia, (766). rugulosum, Cerithium, 766. runcinata, Turrilella (Colpospira), 769ii. Rupellaria, 332, 354, 355. 1022 San Diego Society of Natural History Memoirs rupestris, Purpura, 71S. Thaw (Nucella), (718). Rupieola, 256. rushi, Cadulus, 439. russa, Natica (Cryplonatica), 79S. Natica (Tectonalica) , 798, 798-799. ruslica, Columbella, 697. Pyrene, 682, (697). Tegula (Chlorostoma) , (829), 829, 830. rusticoides, Pyrene, 682. rusticus, Trochus, 829. rutila, Eulima, 863. Melanella, 863. sahulosa, Macovm, (369), 370. Tellina, 369. Sacella, 119, 120-122, 123, 126. sacerdos, Clfiralithi, .509. sachalinens-is, Mnctra, 392. Sacramento River, 66. sacrala, Cerithidea, 763. sacralum, Cerilhiuin (Potamis), 763. sadoensis, Nuculana, 119. Pleurotoma, 554. Spirotropis (Anliplanes) , (554), 555. Salinas Valley, 28, 58. salmonea, Msera, 359. Psephidia ?, 338. Psephis, 33S. Tellina, 359. Tellina (Moerella), 359. sammamishensis, Mytilus, 245. San Andreas fault, 54, 55. San Bernardino, 63. San Bernard no Moiuitains, 44. San Clemente Island, 49, 63, 64. sanctsecrucis, Fu^us, 431. Ludna (Miltha), (291). PhaaMes (Miltha), 291. Priscofusu^, 491. sanctse-marise, Cancellaria, 620. sanctaE'-mo?uc!f, Bela, 531. Lora, 531-532, 534. sancta-monicae, Lora, 531. sancti-ludovici, Pecten., 51, 168, 16S, 169, 170. San Diegan, 70. San Diego, basin, !S, 45-49, 59, 61 (table), 65; Bay, 75 (table); embayment, 39; formation, 34, 40, 45-48, 50, 51, 60, 61 (table), 69 (table). Mesa, 25, 46-49 (47 diagram); old terraces, 48, 56, 59; River valley, 46, 47 (diagram); Pleistocene terraces, 39, 46-49, 62, 73; Pliocene, 41, 45-47 (diagram); zone, 31 (diagram), 32, 34, 40, 41, 61 (table), 70, 102- 106 (as middle Pliocene). sanesia, Odostomia (Amaura), 877. San Francisco, Bay, 65-66, 75 (table), 76. Peninsula, 54. San Gabriel Mountains, 29-30, 37. Sangamon interglacial, 75 (table). San Gorgonio Pass, 49. sanguinea, Cyprsea, 754. Leptothyra, 821. Trivia, 764, 754, "54. Turritella, 770. sanguineum, Homalopoma, (821), 821, 821, 822n. sanguineus, Leptonyx, 821. Turbo, 821. Sanguinolaria, 369, 37 1, 382, 383-384. Sanguiiiokiriidse, 381-385. sanguinolenta, Pecten (Pallium), 171. Purpura, 643. Sanguinolaria, (383). sanguinolentus, Cantharus, 649. Solen. 383. San Joaquin basin, 8, 28, 30, 34, 51-53, 58, 59, 60, 61 (table), 71. sanjuanense, Bittium ( — ), 763. sanjuanensis, Pecten (Propeamussium) , 238. Pecten (Pseudamusium), 238. San Luis Obispo region, 59. San Martinez Grande Canyon, 33, 103, 105, 106. San Martinez Chiquito Canyon, 34, 103, 105, 106. San Pablo formation, 28n., 59. San Pedro, formation, 31 (diagram), 37, 41, 71; Hill, 42, 45, 49, 63, 64, 65, 73; lower San Pedro series, 36, 37, 40, 41, 61 (table); Pleistocene faunas of, 36, 40, 41, 42, 43-44; Pleistocene species at, 20; upper San Pedro series, 37, 40, 41, 43, 45, 61 (table), 73; zone, 37, 40, 41, 42, 44, 61 (table), 69 (table), 71, 75 (table). Santa Barbara formation, 35-36; terrace, 38-39, 64, 65, 73; zone, 31 (diagram), 32, 35-36, 37, 40, 41, 42, 46, 53, 60, 61 (table), 62, 69 (table), 70, 71, 75 (table), 76n. (on 77), 101, 102, 103, 104, 105. santa-barbarensis, Anachis ( — ), 689. Santa Catalina Island, 63, 64. Santa Clara formation, 61 (table), 62. Santa Clara Valley of the South, see Ventura basin; 62. Santa Clara Valley fault, 38. Santa Cruz, 54, 56. santsecrucis, Ludna (Miltha), (291). Phacoides, 291. santsecrtms, Lucina (Miltha), (291). Phacoides, 291. Santa Margarita formation, 28, 29, 31 (diagram), 51, 59. Santa Maria district, 38. Santa Monica Mountains, 59; see also Temescal Canyon. Santa Paula formation, 32, 60. saniarosA, Tellina, 358. Santa Rosalia, 51. santarosana, Anliplanes, 553. Pleurotoma, 553. Spirotropis (Anliplanes), (553), (554), 555. Volume I ' Pliocene and Pleistocene Molltjsca of California 1023 sarda, Marginella, 629. Persicula (Closia), (629). Sargent oil field, 56, 59. sarsii, Bela, 521. Lora, (521). satura, Neptunea, 651 (twice), 653, 654, 716. Odostomia (Amaura), 876. salumlis, AuachU (Chauvelia), 688. satnriia, Neptunea, (754). saturnum, Buccinum, 654- saturuDi, Buccinum, 654- saturus, Chrysodomus, 654, '^16. Saugus formation, .31 (diagram), 33, 34, 34, 36, 40, 62. saugusensis, Crepidula, 790. saundersi, Buccinum, 669. Sawyer Ridge, 55. Saxicava, 97, 355, 419 (twice), 425n., 427-429. Saxicavids^, 423-429. saxicola. Purpura, 717. Purpura (Polytropa), 717. Thais (Nucella), [717). Saxidomus, 325, 333, 340, 341-342. saxosus. Turbo (Callopoma), 816, 816-817. sayaria, Chlamys (Lyropecten), (176n.). sayanu^, Chlamys (Lyropecten), 176n. Pecten (Lyropecten), 176n. scaber, Triton, 735. scabra, Acmcea, 810, 811. Patella. SIO. Patella (Lottia ?), 811. Ranella (Priene), (725), 735. scabrum, Argobuccinum, 735. Scala, 852, 8-53, 5.5.5, 8.56, 857, 858, 8.59, 860. scalare, Epitonium, (852). Scalaria, 76.9)1., 8-52, 8.53, 856, 8-57, 858, 8.59. scalariformis, Trophon (Boreotrophon), 723. scalarina, Anachis, (684, twice), 689. Columbella, 684 (twice). Perrot.a, 611. scalaris, Bela. 516, 530. Conus, 475-476, 476. Defrancia, 515. Ischnula, 512. Lora, (512), 515, (515), 516, 517, (530), 530, 537. Turbo, 8.52. scalaroides, Bela, 516, 519. Lora, (516), 517 (three times), (519). Scaldi.sien, 69 (table). scammoni, Mangelia (Agathotoma) , (601). Philbertia, 601. Scandinavia, 67, 68, 73, 76. Scaphander, 451-452, 455, 456. Scaphandrida?, 451-455, 455. Scapharca, 137, 138, 139, I40, I4I. Scaphopoda, 436-439. scapina, Yoldia (Orthoyoldia) , 128n. scarlatina, Cabestana (Septa), (732n.). Septa, 732n. scelera, Odostomia (Chrysallida), 873. schantarica, Bela, 533. Lora, 5.32, 533, 534, .535, 537. schantaricum, Pleurotoma, 533. Schenck, Hubert G., 8. Schizodesma, 4OO, 403, 403, 404- Schizopyga, 671, 672-676, (;77, 678, 941. Schizothsrus, 281, 400, 404-406, 406, 410. schizotoma. Area, I40. sckmidti, Bela, 537. Lora, 531, 537. schneideri, Lora, 517, 518-519, 519 (twice), 520, 521. schraderi, Pyrulofusus, 652. V olutopsiwi (Pyrulofusus), 652. Scissodesma, 403. scissurata. Yoldia, 128n., 129, 130, 131-132, pi. 1, fig. 1. Scobina, 431- Scohinella. 481 (diagram), 482, 483. Scobinopholas, 431-432. seopulosa, Stomatia, 806. scopulosum, Sinum, 806, 807. scopulosus, Catinvs, 806. Sigaretus, 806. scortuni, "Donax," 379. Venus, 379. scotiaensis, Argobuccinum, 738. Chrysodomus, 660. Neptunea (Sulcosipho), 658, 660. Ranella (Priene), 738. Scotland, 68. Scripps, Miss Ellen Browning, 5, 9. scripta, Columbella, 690, 697. Mitrella, 684 (twice), (689), (690, twice), 690 (twice), text fig. 6, (697). scriptus, Murex, 689, 690 (twice). Scrobicularia, 364- sculptum, Cerithium, 757. Thericium, (757). sculpturata, Lora, 527, 627, 596. Mangilia, 527, 595. Ostrea, 153. scul} turatus, Petaloccmchiis, 778. scutellatum, Crticibulutn , 793. scu ulata, Littorina, 782, pi. 32, figs. 16, 17, 18. Littorina (Melarhape), 782. Seacliff, 65, 101. Searlesia, 642, 644, 644-646, 729. sebatia, Bornia, (301). Cyclas, 301. Second Street, San Pedro, 42, 43. secta, Macoma, 370, 373, 374, 387, pi. 20, figs. 6a, 66. Macoma (Rexithserus) , 374. Tellina, 374. Sections, see subgenera and groups. securis, Venus (Chione), 21, 30, 34, 46,''319 (twice), 320- 321, pi. 17, fig. 1. I^i Sedimentary cycles (see also littoral zones), 19, 23, 26, 28, 29, 37, 46, 50, 52, 55, 58, 59, 62, 66, 70, 71. Sedimentation, 24, 26, 43, 77. Sella, 764. Semele, 295, 375-377. SemelUs, 375-378. semen, Retusa, 445. semiasper, Taras, 294, 294. semiaspera, Diplodonta, 294. semi-asperum, Cardium, 310. Lsevicardium (N emocardium) , (310). Semibittium, 759 (twice), 760, 761-763. 1024 San Diego Society of Natural History ■ Memoirs Semicassis, 670. semicaudata , J ouannetia, 433n. semicostata, Homotoma, 609. Peratotoma ?, (609). Raphitoma ?, (609). semiinflata, Pseudomelatoma, 561-562, 938, pi. 26, fig. 19. semilamellosa, Amiantis, [350). Cyther a, 350. Dime, 350. semiplicata, Lora, 529. Venus (Chione), 321. semipolitum, Denlalium, 436-437. sernipunctala , ColumheUa, 680. Pyrene, {680). semiraMatuts, Pecten (Propeamussium), 233. seir.irostrata, Nucula (Acila), 113-115, text figs. 2a, 2b, 3a, 36. semirugosa, Diplodonla, 394. semirugosus, Taras, (294). semistriatum, Denlalium, (436-437), 437. semisulcata, Astarte, 267 . Sene.ctus, 815. senegalensis, Murex (Siratus), 729n. senescens, Pecten {Aeguipecten), 210. Septa, 732, 733. septangnlaris, Bela, 589. Bellaspira, (.584), (589). Hsedro pie lira, 584. Murex, 584. septemnarius, Pecten, (Lyropecten) , 178. sepiemradiatimi, Pecten {Pallium), 235, 236. septemradiatus, Pecten {Pallium), 175, 236. septenarius, Pecten {Lyropeclen) , 177, 178, 178. septenlrionalis, Axinxa, 134- Glycimeris, 134- Glycymeris, 134-136, 40S, ])!. 1, figs. 21a, 216. Pectuncvlu.^, 134- Purpura, 717. Thai^ {.Xiicilla), (717). Septifer, 247-248. seqiiens, Ostrea, 34, 153. sericata, Diplodonta, 295. Felaniella, 295. Lucina, 295. sericatus, Taras, 294 (four times), 295, pi. 14, figs. 12a, 126. Serpula, 776. serpuloides, Delphinoidea, (844). Helix, 844. Serpulorhis, 777, 930. Serrata, 628. serrata, Anachis { — ), 689. Divaricella, (295). Lucina, 395. Marginella (Serrata), 628. serricata. Dip odonta, 295. serricatus. Tarns, {295). Serripcs, 292, 313-314. Serrula, 379-381. serrata, Pknrotoma, 490. Turricula ( Pleurofusia) , (490). xrrnilnidra, Pleurotoma, 490. scrralt. laylori, Nuculana (Adniiui), 119n. layloriana, Oslna, 153-154, l->4. Tectarins, 817. Tectonatica, 796, 797-799. tectula, Natica [Tectonatica), 797. Teeth, of the Vcnmd», 316, 317, 324-325, 341', 341, 344, 351; see also taxodont. Tegelen stage, 67, 69 (table), 71, 75 (table). Tegula, 820, 825-831. ti-cjidn, Alcctrioii (Zeuxis), 671. Arcularia, 671 . Nassa, 671. Nassarius, 671, ]il. 26, fig. 43. legulus, Aleclrion (Schizopyga), 671. telarnon, Mangelia (Agalholmna f), (601). Mangelia (Zetekia ?), (600). Philbertia, 600, 601. telemus, Camlina, 440-441. Motiociilus, .'^JfO. Teleodesmacea, 266-435. Tdlimya, 299, 301, 301. tellimyalis, Pctricola, 356n. Psephis, 356. Telliiia. 260, 26.5, 281, 2S4n., 291, 293, 295, 298, 299, 357-363, .163-.374, 372, 375, 381, 382; s. .v., 357-358, 359, 360. Tellinacea, 357-385. Tellinella, 357. Tellinids, 8, 357-375. Temblor formation, 28, 31 (diagram). temblorensis, TurrileHa, 775. Venus (Chionc), 319, 319-320. Icmelenla, Trilonalia, 713, 714. tetnelenius, Murex, 713. Temescal Canyon, 40, 61 (table). lenebrosum, Buccinuiii, 669. tenera, Macoma, 365, 369. tenerrima, Paphia (Protothaca), 327. Tapes, 327. Ve7ieriipis (Callitlwca), 327-328, pi. 18, figs. 9a, 9b. lentaculata, Bithynia, 68. tenue, Buccinani, 668. Crucibulum, 793. tenuicornis, Mnrcr (Chicnrvus), 707n. Purpura (Ccntrifuga) ?, (707). tenuicostata. Beta, 540. Lara, 539, 540, 640-541. tenuicula, Cheinnitzia, 87(1. TurhoniUa (Pyrgiscus), 870-871. tenmgranosus, Pcctcn, 169. tenuUineata, Mitrella, 694, 698. tenuUirata, Beta, 535. Lara, 515, 531, 533, 533, .534, 534, 535-536, .536, .537, 540. tenuirosiris, Macoma, 374. Macoma (Re.xithxrus) , 374. tenuis. Area, 111. Corbula, 421, 421. Niicula, 111-112. Odostowia ( — ), 874. Odostomia (Evalea), 874- Oliva, 628n. Olivella, 628. Panope, 425. Pecten, 163n. Pctricola, 356. ienuisculpta, Acmxa, 810. Boreotrophon, 725. Lucina (Myrtea), 285, 288, 288-289, 290, 908. Neptunea, 725. Phacoides, 288. icnuisculplus, Phacoides {Parmlucina), 288. Trophon (Boreotrophon), 725. Trophon (Neptuii^a), 725. Trophon (Trophonopsis). 725. tenuispina, Murex, 704. tenuissima , Lora, 537. Yoldia, 129, n. tepoeana, Crassispira, 582. tepocanus, Clnviis (Crassisjnra) , 582, 583. Terebra, 464-470, ,564, 611; .s. s., 464-465, 466. terebra. Turbo, 769. Turrilella, 769. terebrans, Chemnitzia, 870. Turbonilla (Pyrgiscus), (870). Terebratalia, see occidentalis. Terebratula, 69 (table). Terebridae, 464-470, 480, 611. Teredo, 930. Teres, 481 (diagram), 504, .540, 572, 572-573. teres, Pleurotoma, 573. "Pleurotoma," 573. Teres, (573). leresa, Odostomia (Evalea), 875. Teretia, 572. terminumbonis, Area iNavicula), 21, 30, 142-143. 143, pi. 1, figs. \Sa-c, 19a-c, 20a-c, 22. terminus, Pecten (Lyropecten), 186. terpsichore. Anachis ( — ), 689. Terraces, marine, 19, 24-25, 38, 39, 45, 46-49, 51, 56, .57, 61 (table), 62, 63, 64, 65, 69 (table), 72, 73, 74, 75 (table), 76n., 101 ; terrestrial, 25, 37-38, 39, 49, 55, .56, 61 (table), 62, 63, 67, 68, 69 (table), 73, 74. tcrricula, Ivara, 873. Odostomia (Ivara), 873 (twice). lersa, Macoma, (366). Tellina, 366. Tertiary man, 71. tesseUata, Anachis ( — ), 688. Cancellaria (Aphera), 612. Mitra, 634. 1030 San Diego Society of Natural History [ Memoirs tesiacea, Oliva, 625. lethys, Murex (Odncbra), 713. Trilonalia, 713, 713-714. tetraschistus, Cadulun, 438n. CadulvK (Polyschides), 4S8n. TetraslomeUa, 691n. tetrica, Lima, 239. Radula, 2S9. Ihaca, Chama, 328. VeneruTpis (Prolothaca), (328). Thais, 6U, 653, 715-719, 721, 729. thalsea, Antiplanes, 553, 55J,, 566. Pleurotoma, 553. Spirotropis (Anliplanes), (5.53), (554), 555, (556). thalassica, Lora, 511. Pleurolomella, 511. ihalassoma, Clathurelki, 607. Glyphostoma, 607n. thalea, Claims (Cymalosyrinx), 586. Thalolia, 837, 837. Thames, terraces of, 67, 69 (table), 73. thea, Tegula (—), 831. Thecosomata, 440. Thericium, 757. thersites, Eulima, 862. Eidima (Balds), 862. Melanella, 862. Siphonaria, 463. Thesbia, 481 (diagram), 541, 543, 698. Thetis, 269, 269. Thiara, 636, 636. Third Street tunnel, Los Angeles, 40, 61 (table). thomasi, Vitrinella, 843. thomasiana, Cancellaria, 21, 621. thouarsi, Ventis (Antigona), 317. Thovana, 430. Thrada, 256-260; s. s., 256-259, 259. thradsejormis, Yoldia, 127, 128, pi. 1, figs. 12a, 126. Thradida;, 256-260, 880. Thyasira, 97, 281-282, 284, 285. Thyasiridx, 281-282, 285. Thylacodes, 777. Tiara, 636-637, 636. tiarula, Arndaria, 671. Bucdnum, 671n. Nassarius, (671). tigerrinus, Peclen (Pallium), 173. tigrina, Pleurotoma, 503. Turns, (503), 505. Turntella, 774. tigrinus, Pecten ( — ), 173. tigris, Cyprsea, 752. Peclen (Pallium), 171. tillamookensis, Pecten (Pseudarnusium) , 237. Pecten (Pseudamussium), (237). Timber Canyon 35; shown on sketch map, 27; localities near 103, 105; Timber Canyon fanglomerate, 37, 38, 63, (see also older fanglomerate, etc.); Timber Canyon surface, 38, 55; Younger fanglomerate, 39. timessa, Odostomia (Amaura), 877. Timms Point zone, 37, 40, 41, 42, 43, 44, 61 (table), 63 69 (table), 71, 75 (table). tincta, Anachis ( — ), 689. Nitidoscala, 859. Scala, 859, 860. Scalaria, 859. Tegula (Chlorostoma), 826, 828. linctum, Ejntonium (Nitidiscala) , 859-860. Epitonium (Nitidoscala), 860. Tindaria, 132. Tipton, 53. titan, Miira, 636. Tivchi. 339-340, .iW. togatu, tSoUniya, 109. Tellina, 109. lolmani, Pecten (Aequipecten) , 201. lolmiei, Cadulus, 439. Tomella, 611 (twice), 612. Tomlin, J. R. LeB., 9. Tomopleura, 573. Tonna, 740, 741. Tonnidie. 740-741. Topanga formation, see Temblor. topangensis, Chicoreus (Murithais) or Trilonalia, 729. Odnebra, 729n. Tectarius ?, (817). Turbo ?, 817. tornatu, Surcula, 486. Turricula, (486). Turns, 486. Tornatella, 442, 443. Tornatells'a, 442. tornatilis, Acteon, 442. Valuta, 442. Tornatina, 44'5, 44^', n., 44"^, 448, 449. Tornatinidse, 4^1. tornatum, Turris, 486. tornalus, Conus, 477. Murex, 486. toroense, Epitonium (Sthenorytis), 855. tarosa, Drillia, 562. Pseudomelatortm, 544, 546, 559, 561, 562-563, 563 (twice), 938, pi. 26, fig. 20. lorquata, Chemnitzia, 867 (three times). Turbonilla (Strioturbonilla) , 867 (twice), 867, (867). tortuosa. Area (Trisidos), 137, 138, 144. townsendensis, Sanguinolaria, 384. lownsendi, Nucula, 112. Stroinbiformis, 865. Toxoglossa, 464-623. Trachycardium, 305-307. Trachylochetus, 481 (diagram 1, 485-486. trampaseyisis. Bursa, 735. Mytilus (M ytiloconcha ?), 246. Ranella (Priene), (735), 736. tranguebarica, Nassa, 646. trangiieburicum, Bucdnum, 646. trnnquelxiricus. Canlharus, (646), 646, 729. 7V(i nsen n clhi ,338-339. iraiisliratuin, Calliostoma, 833. translucens, Jeffreysia, 787. Syncera, 787. Volume I ^ Pliocene and Pleistocene Mollusca of California 1031 Iransmontana, Aimtina (Raeta ?), 406, 408, 409, 409, pi. 22, fig. 2. Lulrarw, 409. Iransversa, Malleiia, (132). Psendomalletia, 132. trapezia, Chama, 276. Glans, (276). trapezina, Fissurellidea, 84Sn. Megatebenmis (Ainhlychilepas), (S48n.). irapezoidea, Thraria, ,'■>?. trapezmdes, Thraria, 267-258, 258, pi. 13, fig. 8. Iraski, Actseon, 442. Acteon, 442-443. Fiisinm. {639). tremperi, Epitoniiim (Opalia), 854. tremperiana, Balhyloma, 499. treniperianui, Cryptoconus, 499. Surculites (Megasurcula), 499, 500. Tresiis, 404. irevelliaiia, Ischnula, 512. Lora, (512), {522), 523. Mangelia {Bda), 522. trenellianum, Pleurotoma, 522. trevelyana, Bela, 522. Lora, {322), {553). Pleurotoma. 522. 553. trevyUiana, Pleurotoma {Isehnula), 522. trialata, Alipurpura, 706. Purpura, 706. tr alalus, Murex, 706. Murex (Alip-urpura), 706. Murex {Chicoreus), 706. triangularis. Aemxa, 812. Cancellaria, 621. triarigulatus, Trophon {Awitrotrophon), 724, 726. Trophon { Boreotrophon f), 724-725, 726, 726. tribulus. Cancellaria, 618, (618). Murex, 704. Voluta, 61S. trichodes, ClatliurcUa, 608. Philhertia, 60S. Trichotropidse, 767. Trichotropis, 615, 767. Tricolea, SIS. Tricolia, 813-815. Tricoliidse, S13. tricolor, Calliostoma, 836, 836. Tapes, 329. Venerupis (Protothaca) , {328). Venus, 328. tricuspida, Carolina, 441. Hyalsea, 441- iridentata, Anotnia, 440. Carolina, 440, 441- Chenmitzia, 871. Hyalsea, 440- Turhonilla (Lancea), 871. Turbonilla {Mormula), 871-872. Tridonta, 266. Trifora, 766, 767. Triforis, 766. trigenarium, Sinum, {806). Sinum {Sigaretus), 806. Irigonalis, Tivela. 340. Trigonella, 340, 390. Trigonia, 338. Trigoniocardia, 313. trigonoides, Cardium, 303. Didacna, (303). Trigonostoma, 622n. trigonostoma, Cancellaria, 622. Trigona, {622). trigonidaris, Cumingia, 378. Trigon ulina , 266. trilineata. Area, 21, 34, 46, 138, 139, 139-141, 955, pi. 2, figs. 1, 4. Area {Seapharca), 140. trinominata. Modiolus, 251. Volsella. 251. trinominatus. Modiolus, {251). tripherus, Trophon {Boreotrophon), 724n. triphooki, Perten {Phialopecten), 189n. Triphora, 766-767. Triphoridse, 766-767. Triphoris, 766, 767. Triplex, 728, 729. trigueter, "Murex," 725n. triquetra, Eupleura, {714)- Ranella, 714- Triremis, 708 (twice), n. triremis, Aranea, 704- Murex, {704). Trisidos, 138, 144. Trisis, 144- tristoma, Cerithium, 766. Triphora, (766). Trilia, 672, 674, 675. triticea. Bulla, 453. Cylichna, (453). Triton, 646, 648, 732, n., 733, n., 7S4n., 735, 736, 737; sp., 733. TritonaUa, 599, 653, 708-714. 729. Tritonidea, 646 (twicpi. tritonidea, Cancellaria, 21, 30, 73, 497, 616, 616-619, 619, 620 (twice), 621 (twice), 942, pi. 27, fig. 8; s. s., 616-617, 617, 618 (twice), 619 (twice). Cancellaria {Euclia), 616. tritonis, "Murex," 732n. Tritonium, 512, 513, 514, 518, 529, 543, 622, 651n., 652, 653, 653, 654, 668, 698n., 711, 733, 737. tritonium, Perrona, 611. Tritonofusus. 661, 663, 665. Trivia, 753-764. Trochatella, 794. Trochida', 815, 820, 823-842. trochiformis. Calyptrsea {Trochila), 795, 795-796, pi. 31, fig. II. Patella, 795. trochilia, Odostomii {Amaura), 877. Trochiscus, 824. Trochila, 794, 795, 795-796. Trochus, 785, 795, 816, 817, n., 818, 820, 823-824, 825, 825, 826, 827, 829, 830, 831, n.. S32. S33, 835, 839, 840. Trophon, .571, 644, 645n., 716, 716n., 720-725, 726, 727, 727, 728. 1032 San Diego Society of Natural History Memoirs Trui lumopsix, 721, 725. Trnphosijcon, 33, 46, 50, 743-751. Trojnilocardiiim, 302. Tropimircida, 4S9. Truncacila, 115-117; see also castrcnsis group, 114. Truncaria, 701. truncata, Cryptoinya, 418. Macoma, {373). Mya, 410, 411 (twice), 412, 413, 414-415, 415. Nucula, 127. Plagiosloma, 236. Tellina, 373, 373. Yoldia, (127). Truncatella, 787. Truncatellidse, 787. truncalus, Peclen (Pseudamussium), (236). irunculala, Relusa (Coleophysis), (446n.). trunculatus, Ulriculus, 446n. Irunculus, Chicoreus (Murithais), (729), 729, 730. Donax, 379. Murex, 729. tryblium, Peclen (Palinopeclen) , 197. trymiiana, Balhytoma, 498. Dolichotoma, 498. Genota, 498. Pleuroloma, 495, 498. Pseudotoma, 498. Surcula, 4.95, 498. Turris, 498. Iryonianus, Cryptoconus, 498. SurcuUtes (Megasurnda), 495, 496, 498-499, 499, 500. lubercularis, Cerithiopsis, (764). Murex, 764. tubercidata, Pleuroloma, 573. Ranclla, 734 or 73/,. luberculatus, Teres (Aslhenotoma) , (573), 573. tubercuUfera, Clavalula (Knefaslia), 484, 485, ])1. 25, figs. 10a, 106. Pleuroloma, 485. Surcula, 485. tuberculosa, Area, 141. Area (Anadara), I4I. Area (Scapharca), I41. Clavalula, 611. tuberosa, Amycla, 697. Aslyris, 697. Cabestana (GuUuruium), (733n.), (73411.) or (734n.). Cabestana (Monoplex), (734n.) or (734n.). Columbella, 697. Columbella (Alia), 6.97. Milrella, 40S, 697-698, pi. 26, fig. 45. iuherosum, Triloii, 733n., 734n. t^iberosus, Triton, 733n. Tubicauda, 725n. tubifer, "Murex," 725n. tiibuUfera, Ostrea, 150. Tuceta, 133. Tulare, 52; formation or lake beds, 53, 61 (table), 62. tulipa, Fasciolaria, (637). Murex, 637. luinhezensis, Peclen (Aequi peclen), 199, 203, 205, 206, 206. Peclen (Chlamys), 'Jim. Imnens, Hipponix, 788-789. Pilar, (344). Venus, 344- tumida. My sella, 301. Relusa (Acleocina), 449. Rochefortia, 301, pi. 14, figs. 16, 17. Tellimya, 301. Tornalina, 449- tumidus, Peclen ( — ), 218. Peclen (Aequi peclen), 218. tunica, Peclen (Aequipecten), 204- turbanica, Aslrsea (Pomaidax), 819, pi. 31, fig. 2. turbanicus, Pomaulax, 819n. lurbinala, Clionella, (564). Melatoma, (564). turbinatus. Boletus, 564- TurUnidse, 815 823, 823. Turbo, 769, 781. 813. 81'-817, 821, 822. n., 824, S4O, 852. TurboHilla, 760, 865. 865-872. Turcica, 837-838. Turcicula, 838. turgida, Apolyinetis (?), (364). Tellina. 364. turgi.dula, Milrella, 689. turneri, Peclen { Palinopeclen), 55, 194, 194. Turricula, 479, 480, 481 (diagram), 482, 483, 484, 490, 492, 493, 494, 501, 502, 503, 504, 507, 542, 545, 547 (three times), 549, 559, 562, 579, 579n.,, 590, 610, 934; .s s., 481 (diagram), 486-489, 490. turricula, Bela, 512, 515, 516. Isehnula, 512. Lora, 91, (512, twice), 513, 515, 515-520, 520, 522, 523, 524, 525, 526, 532, 537, 594, pi figs. 42, 43; s. s., 515-517, 519, 521. Mangelia (Bela), 515. Murex, 512, 515. Odosto?nia (I vara), 873. Propebela, 512. Turridse, 8, 13, 20, 93, 97, 477-612, 665, n., 698. Turridrupa, 573. Turris, 478, 480, 481 (diagram), 482, 482, 483 (twice), 484n., 486, 486, 487, 489, 491, 493n., 495, 497, 498, 502, 503-505, 507, 520, 548, 549, 553, 556, 657, 566, 567, .568, 569, 569, 571 (twice), 571, 574, 580,582n., 590, 590, 712; s. s., 481 (diagram). 503, 505. turris, "Pleiirotoni.a,", 510. Purpura, 710. Tritonalia, 709, 710. turrita, Strombinu, 700. Turr tella, 761, 769-775, 775, 776, 776. Turritella nova zone, 52, 61 (table). Turritellidif, 769-776. Turritellopsis, 775-776. Turritellus, 769. Turritidse, 4"^^- Turritriton, 732, 732. 486- 509, 575, 521, 32, Volume I ■ Pliocene and Pleistocene Mollusca of California 1033 lurtoni, Fusus, 651n. Jumala, (65tn.). Neptunea (Volutopsius), 651n. Volutopsius (Jumala), (651n.). Tylotia, 574. Type species, determination of, 83-85; should lie re- garded merely as anchors, not affecting classifi- cation, 85. Typhina, T2bn. Typhinellus, 725n. Typhis, 725n., 725n. Typhisopsis, 725n. Typhlomangelin, 4S1 (diagram), 511, 543, 5-14 (twice), 545, 547, 549-550, 553, 558. lyjnca, Mactra (Muliida), 4OO. Phasianella (E uliihidium) , 815. TricoUa, SI 4. iypicum, Eulithidium, 815. u uber, Nalica, 7.99. Poliinces, 799, text fig. 12. ■iMevallensis, Mya, 415. Vkko, 651n. ivmhifer, Murex, 709n. wtibifera, Pterorytis, (70!)n.). Tritonalia (Plerorylis) , (709n.). umbilicata, Driliia, 583, 584. Pleurotoma, 584. Tegula (Chlorosloma), 828. umhilicalus. Claims (Driliia), (583), (584), 584. I'mbilicus, illustrated, 796. iniihoiialn, Glycymeru .', 309n. umbonaltis, Pedunculus, 309n. umbrellum, Crunbulum, 793. unalaskensis, Admete, (623). Cancellaria, 623. unca, Leda, 123. Nuculana, (123). uncinaia, Columbella, 680n. Microcithara, 680. Unconformities (see also diastrophic movements and revolutions), 24, 32, 37, 44, .50, 51, 53, 56, 63, 70. unda, Apolymelis (?), (364). Arcopagia, 364. undata, Mysia, (293). Venus, 293. undatella, Chione, 322. Venus (Chione), 321, 323, 914. undaiuni, Buccimitn, 652, 667. Tritonium, 652. imdosa, Astra-a (Pomaulax), (S17), SIS, 818, 819, 820, pi. 31, figs. 6a, 66, 7. Imperator, 818. Nassa, 646. undosum, Astralium (Pomaulax), 818. Buccinum, 646. uiidosu-s, Astra-a (Pomaulax), 818. Cantharus, (646). Pomaulax, 818. uiidosus — conlitiued. THton, 646. Trochus, 817, 818. umbdata, Analina (Raeta), 407, 408, pi. 23, figs. 5a, 56, 5c. Crassatelliles, 271, 271. Cyaihodonta, 2.57, 259. Labiosa, 407. Raeta, 407. Thracia (Cyaihodonta), (257), (259), 259, pi. 13, figs. 6a, 66. unedo, Fragum, 312. ungana, Saxicava, 427. unguiculus, Peden (Propeamussium) , 233. unguis, Aslrsea (Umnilla). SIS. Ungulinidie, 13, 285, 292-297. unica, Diodora, 851. Fissurid a, 851. Neptunea (Sulcosipho), 657, (660), 660, 661. unicarinata, Acanthina, 720. unicum, Buccinum, 660 (twice). unicus, Chrysodomus (Ancislrolepis) , 660. unifasciata, Chemnitzia, 870. Columbella, 689. Lacuna, 783. Mitrella, (689). Natica, 797, text fig. 10. Scalaria, 857. Turbonilla (Pyrgiscus), (870). unifasciatum,, Epitonium (Nitidiscala), (857). unim.aculatus, Clavus, 489, 559, 575 (twice), 579, pi. 26, figs. 2a, 26. Unio, 414, 429. Unionium, 147, 148. unispinosa, Euplcura, 714. urceolata, Cancellaria, 613, 613-614. Uromitra, 636. Urosaljinx, 711. v^ia, Felania, 294. ustiis, Taras, (294). Utriculus, 445, 44('n. Uvanilla, 818. Uzita, 670, 671, 678-679. V vaccamacensis, Pecten (Lyropecten ?), 191. Pecten (Nodopecten), Win. vagina, Solen, 385. vahlii, Lora, 529. valdezi, Turbonilla (Pyrgolampron), 868. Valenciennes, 475n. valga, Buccinum, 701. "Buccinum," 701. Vanatta, E. G., 9. vancouverensis, Acteon (Riclaxis), 443, 444. Pecten (Pseudannisium), 238. Pecten (Pseudamussium), 194, 234, 236, 238. Polinices (Neverila), 803 (twice). vanvlecki, Macoma, 375. Pecten, 22 In. Pecten (Janira), 221. Turritella, 21, 34, 772, 773, pi. 24, fig. 22. 1034 San Diego Society of Natural History Memoirs vanwinkles-, Pccten (Pwudamussium), 237. Vaqueros formation, 28, 31 (diagram), 57, 58. vagxierosense, Cardium, SOT. Lsevicardium (Trachycardium) , (307). varia, Anachis ( — ), 689. Marginella (Volvarina\ 630. lAltoritm, 782. Volvarina, 630. variabilis, Murex, 725. Persicula, 629. Trophon (Trophonopsis) , (725). Variamussium., 232, 235. varians, Anachis ( — ), 689, 689. variaia, Turritella, 775n. Variation, of characters in species, 13, 90-93; of Pectens, 15.5-156, 167, 172-173, 177, 180-182, 184, 187, 207, 207-209, 21.5-218, 219, 224, 225, 227, 229, etc.; of other groups, 273, 322, 330-331, 388, 397, 399, 402, 411, 413, 415, 418, 467-468, 483, 513-514, 515, 516-517, 530, 540, 550, 553, 554-555, 577, 578, 588, 590-591, 617, 643-644, 645, 653, 655, 660- 661, 674, 685, 690, 693, 709, 717, 732, 748, 749, 750, 751, 772, 773, 7S0, 783, 786, 854, 914, 933, etc.; of generic characters, 93, 175, 229-230, 326, 346, 478-482, 487, 493, 500, .50:3-504, 507, .508, 509, 510, 511, 513, 54.3-.545, .547, .5.59, .575, .579, 585- 586, 588, .589, 600-601, 604-605, 611-612, 648, 653, 658, 660, 661, 662, 664, 664-665, 670, 679, 684, 727, 728-7.30, 732, 734, 757, 825, etc. Varicorbula, 420n. mnco.sa. An- chis ( — ), 689. varico.ita.ta, Opalia, 853. varicostatum, Epitonium (Opalia), 853, 853-854, 854, pi. 24, fig. 20. variegata, Eiicosmia, 814, S15. Mangclia (Bela), 590-591, 591, 592 (twice), 593, 594, 597, 598. Papyridea, (311). Phasiandla, 814, 815. Phasianella {Eucosmia), 814, S15. Pleurotoma, 5,90. Pyramidella, 865. "Pyraniidella," 865. Raphiloma, (590). Tellina, (361), 361. Terebra (Striote.rebrum) , 466, 467. Tricolia, (814), 815. Turricula, (590). Turns, 505, (590). variegatum, Calliosiotna, 832 (twice). Cardium, 311. Pleurotoma, 590. variegatus, Angulus, 361. Varieties, distinction between species and varieties, 86- 87; value of using varietal names, 92, 156, 237. varistriata , Tegula ( — ), 831. varius, Pecten, 155n., 168, 169. vaughnni, Pecten. (Lyropecten), 180, 180-181, 182, 187. veatchii, Liropecten, 177, 182. Ostrea, 152, 152. veatchii — continued. Peclen (Lyropecten), 178, 182. Pecten (N odipecten) , 182. vellicala, Kuii, 316n. vellum, Soleniya, 109. Velulina, 807-808. velutina. Bulla, 807, 808. Velutina, (807), 808. Velutinidx, 807-808. Veneracea, 315-357. Venericardia, 94, 272, 272, 273, 274, 275, 276, L76. Veneridse, 8, 13, 270n., 293, 315-354. veneriformis, Astartr, 267. Venerupis, 325, 325-331, 332, 332, 342, 34-1, 351; s. s., 326, 326, 328. venezuelanus, Pecten (Aequipecten), 217 (twice), 218. venilia, Columbella, 682. Pyrene, (682). Ventricola, 317, 317. ventricosa, Amphisxa, 701-702. Bursa, 732. Cardita, 272-273, 274, jil. 18, figs. 9«, 9b, 11. Ficus, 743. Pyrula, 743. Solcmya, 109-110. Venericardia, 272. reiUricosus, Pecten (Aequipecten), 206, 218, 219. Pecten (Plagioctenium) , 218. Ventura basin, 7, 8, 26-39, 40, 41, 42, 45. 51, .52, 55, 56, 58, 59, 60, 61 (table), 62, 63, 70, 71. 101-106.; horizon, 35, 36, 37. venturaei sis, Chrysodoiiius, 656. Neptunea, 35, 656. Pecten, 163, 164. Peclen (Chlamys), 163. venturensis, Pinna (Atrina), I46, 146. venulosa, Tellina, 363, 363. Venus, 266, 267, 276, 281, 283, 285, 293, 316-324, 324, 324-336, 338, 339, 340, 344, 344, 343, 3-50, 351, 354, 3.55, 363, 371, 379, 405; s. s., 316, 317-318, 318, 343. verkriizeni, Neptunea (Coln.'i), (662). Sipho, 662. Vermetidx, 776-778. Vermetus, 776, 777, 778, 930. Vermicularia, 776-777 . Vertniculum, 778. Vermiculus, 776. vernalis, Nacella, 463. Williamia, 463. verrillii, Leucosyrinx, (506). Pleurotoma (Pleurotomella) , 506. verrucosa, Venus, 316, 317, 318, 343. versicolor, Alectrion, 677. Amphissa, 688, 700, 701, 702, pi. 26, fig. .53. Calliostoma, (835). Columbella, 700. Nassa, 677. Nassa (Hima), 677. Nassarius ( — ), 677. Trochus, 835. Verlagus, 758, n. Verticordia, 266. Volume I ] Pliocene and Pleistocene Mollusca of California 1035 Verlicordiidse, 265-266. Vertipecten, 13, 156, 176, 188-191, 192. vesiciila, liNjla, .'f(i(l. Haminea, 460. Haminoea, 460, 460. vesperlina, Macrnndlisla {Chionella), 343. Oslrea, 30, 34, 152-153, pi. 12, figs, lo, lb. velitsta, Cancdlaria, 617, 619, 621. vexaiiva, Turhonilla (Pyrgiscus), 870. vibex, Cantharus ?, (649). Murex, 649. vickereyi, Pecten {Lyropeden) , 184- victoriana, Cythara, 601. Mangelia (Agalhotoma) , (601). vidua, Aslyris (Fluclla), 689. Mitrella, (689). vielliersi, Mangelia, (585). Pleuroloma, 585. Vielliersia, 585. Villiersia, 585, 585. Villiersiella, 585. mlliersii, Mangelia, (585), 585, 937. Pleuroloma, 585, .937. vinosa, Anliplanes, 556. Pleuroloma, 555, 556. Spirolropis (Anliplanes), (555), (556), 556. violacea, Bela, -536, 539, 540. Lora, (535), (536), 537, 538, 540, 541 (twice), (573). Mercenaria, 324- Pleuroloma, 535, 536, 540, 573. Venus (Mercenaria), 324. violaceus. Teres, (573). violascens, Solecurhis, 384. Tagelus, 384. virescens. Bulla, 458. Haminea, 458. Haminoea, 458, 459, 460. virgineum, Calliosloma, (832). virgineus, Trochus, 832. virginiana, Bellaspira, (584). Mangelia, 584. virginianus, Pholas (Barnea), 431. virginica, Oslrea, 149. virginicum, Calliosloma, 834. virgo, Turris, 505. virida, Neplunea (Sulcosipho)? , (661). viridula, Admete, 514, 622. Bela, 514, 533, 9.55. Cancellaria, 622. Defrancia, 512 (four times), 514, 533. Lora, 91, (512, three times), (512, twice), 514-515, 517, 520, 522, (533), 534, (622), 955, .955, pi. 32, figs. 39, 40, 41. Oenopola, 512. Pleurntoma, 514- Tegiila (Chlorostoma), (829), 829. viridulum, Buccinum, 514. Chlorostoma (Omphalius) , 829. Tnlonium, 512, 513, 614, 622. viridvm, Buccinum, 661. vitellus, Natica, (796). Nerila, 796. Vitrinella, 843-844. vittatus, Conus, 477. Vitularia, 711. vivesi, Pteria, 148. vogdesi, Pecten, 228. Peclen (Janira), 221, 227, 228-229, 229, pi. 3, figs. 3a, Zh. Vola, 220, 221, 223, 228. volseformis, Peclen (Lyropeden), 175, 185, 186. Volcanics, Miocene, 50, 58, 59; Triassic, 47 (diiigrani). volcano, FissureUa, 847-848. Volsella,2Hi, 248-252; s. s., 248-251, 252. Voluta, 442, 445, 461n., 612, 618, 623, 624, 626, 628, 628, 629, 633, 633, 634, 680, 683, 696, 753. Volutella, 629, 629, 632. Vohdidse, 482, 633-634, 682. Volutopsis, 508, 650. Volutopsius, (508), 650-652, 6.53. Volvaria, 453. Volvarina, 629, 630. Volvula, 450. Volvidella, 450. Volvulus, 450. voyi, Callista, 395. Drillia, 555. Mactra (Spisula), 97, 395, 395, 397, 399. Pleuroloma, 555. Spirolropis (Anliplanes), 553, 555, 555-556, 557. Spisula (Hemimaclra), 395. vulgaris, Gari, 381. Velutina, 807. mdgalum, Cerithium, 757. Thericium, (757). Vulgocerithium, 757. Vulsella, 248. w loaldorfensis, Claims (Cymatosyrinx), (576), STJ. Drillia, 576. Nassa, 676. Nassarius (Schizopyga) or Nassarius (Tritia), 676. Ocinebra, 713. Tritonalia, 713. Walton-on-Naze, 66, 70. Waltonian, 69 (table). washburnei. Peclen, 162, 163. Washington, 29, 57, 59, 60; fossils from region north of California, 7. icashinglonensis, Cryplomya, 417. Nucula, 112. Scaphander, 452. washingtoni, Eulima, 865. Strombiformis, 864n., (865). washingloniana, Cryplomya, 41~- Fasciolaria, 4S4- washingtonianus, Surculites (Clinura), 494. walsoni, Denlalium, 438. wattsi, Peclen (Chlamys), 173. Pecten (Pallium), 173, 173, 900. waylandi, Peclen (Propeamnssium) , 233. 1036 San Diego Society of Natural History Memoirs Weathering and erosion, effect on shells, 135, 136, 193- 194, 220, 320, 353, 557, 577, 615, 723, 883, 906, 916, 940, etc. weaveri, Pccten (Aequipeclen), 201-202. wetherilH, Acteon, JfJ^G. Relusa (Acieocina), (446). Wetmore, Alexander, 9. Weybourne, 66. Weybournian, 69 (table). whitei, Anachis ( — ), 689. whitmani, Leda (Lembiilus), 12^. Nuculana, 124-125. whitneyi, A'assa, 679. Nassariiis (Uzila), 679, pi. 26, figs. 4Sa, 486. Wildcat formation or series, 54, 55, 56, 57, 59^ 60, 61 (table), 62, 69 (table). wilkesana, Fusus (Hemifuaus), 730. mlkesanus, Ckicoreus (Murithais), 715, 716, n., 728, 729 (three times), 730, pi, 32, fig. 12. vjillameUensis, Leda, 126. Nuculana, 126. WiUett, George, 8. willelti, Astarte, 269. Williamia, 463-464. mlliomsoni. Hittiniu, 766. Cerithiop.-