GIFT OF UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 8, No. 6, pp. 61-180, pis. 6-18 Issued^ 13, 1914 FAUNA OF THE MARTINEZ EOCENE OF CALIFORNIA BY ROY ERNEST DICKERSON esis tied in i if lifornia. UNIVERSITY OF CALIFORNIA PRESS BERKELEY UNIVERSITY OF CALIFORNIA PUBLICATIONS NOTE. — The University of California Publications are offered in exchange for the publi- cations of learned societies and institutions, universities and libraries. Complete lists of all the publications of the University will be sent upon request. For sample copies, lists of publications and other information, address the Manager of the University Press, Berkeley, California, U. S. A. All matter sent in exchange should be addressed to The Exchange Department, University Library, Berkeley, California, U. S. A. OTTO HARRASSOWITZ K. FRIEDLAENDER & SOHN LEIPZIG BERLIN Agent for the series in American Arch- Agent for the series in American Arch- aeology and Ethnology, Classical Philology, aeology and Ethnology, Agricultural Sciences, Economics, Education, History, Modern Botany, Geology, Mathematics, Pathology, Philology, Philosophy, Psychology. Physiology, Zoology, and Memoirs. Geology. — ANDREW C. LAWSON and JOHN C. MERRIAM, Editors. Price per volume, $3.50. Volumes I (pp. 435), II (pp. 450), JII (pp. 475), IV (pp. 462), V (pp. 448), VI (pp. 454), and VII (pp. 500), completed. Vol. VIII in progiv Cited as Univ. Calif. Publ. Bull. Dept. Geol. Volume 1, 1893-1896, 435 pp., with 18 plates, price $3,50 Volume 2, 1896-1902, 450 pp., with 17 plates and 1 map, price $3.50 Volume 3, 1902-1904, 482 pp., with 51 plates, price $3.50 A list of the titles in volumes 1, 2 and 3 will be sent upon request. VOLUME 4. 1. The Geology of the Upper Begion of the Main Walker Eiver, Nevada, by Dwight T. Smith 30c 2. A Primitive Ichthyosaurian Limb from the Middle Triassie of Nevada, by John C. Merriam lOc 3. Geological Section of the Coast Eanges North of the Bay of San Francisco, by V. C. Osmont 40c 4. Areas of the California Neocene, by Vance C. Osmont 15c 5. Contribution to the Palaeontology of the Martinez Group, by Charles E. Weaver 20c 6. New or Imperfectly Known Eodents and Ungulates from the John Day Series, by William J. Sinclair 25c 7. New Mammalia from the Quarternary Caves of California, by William J. Sinclair 25c 8. Preptoceras, a New Ungulate from the Samwel Cave, California, by Eustace L. Furlong lOc 9. A New Sabre-tooth from California, by John C. Merriam 5c 10. The Structure and Genesis of the Comstock Lode, by John A. Eeid 15c 11. The Differential Thermal Conductivities of Certain Schists, by Paul Thelen 25c 12. Sketch of the Geology of Mineral King, California, by A. Knopf and P. Thelen 35c 13. Cold Water Bc:t Along the West Coast of the United States, by Euliff S. Holway 25c 14. The Copper Deposits cf the Itotinson Mining District, Nevada, by Andrew C. Lawson 50c 15. I. Contribution ta. the Classification of the Amphiboles. II. On Some Glaucophane Schlct3, Syenites, etc., by G. Murgoci 35c 16. The Geomorphic Features of the Middle Kern, by Andrew C. Lawson 15c 17. Notes on the Foothill Copper Belt of the Sierra Nevada, by A. Knopf. 18. An Alteration of Coast Eange Serpentine, by A. Knopf. Nos. 17 and 18 in one cover -< 15e 19. The Geomorphogeny of the Tehachapi Valley System, by Andrew C. Lawson 35c VOLUME 5. 1. Carnivora from the Tertiary Formations of the John Day Eegion, by John C. Merriam .'. 60c 2. Some Edentate-like Eemains from the Mascall Beds of Oregon, by William J. Sinclair. 3. Fossil Mollusca from the John Day and Mascall Beds of Oregon, by Eobert E. C. Stearns. os. 2 and 3 in one cover 15c 4. New Cestraciont Teeth from the West American Triassie, by Edna M. Wemple lOc 5. Preliminary Note on a New Marine Eeptile from the Middle Triassie of Nevada, by John C. Merriam 10e UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 8, No. 6, pp. 61-180, pis. 6-18 Issued May 13, 1914 FAUNA OF THE MARTINEZ EOCENE OF CALIFORNIA BY ROY ERNEST DICKERSON CONTENTS PAGE Introduction 64 Review of the Literature 64 Areal Distribution of the Martinez in California 69 Principal Localities 69 Distribution of the Martinez Compared with that of the Tejon 69 Description of the Typical Martinez Sections in California 71 Lower and Middle Zones of Martinez North of Mount Diablo 71 Fauna of the Meretrix dalli Zone 71 Fauna of the Trochocyathus zitteli Zone 74 Martinez and Tejon South of Mount Diablo 77 Type Locality of the Martinez 79 Stratigraphy 79 Relations to the Martinez at Selby Smelter 81 Faunal Zones 81 Martinez at Benicia 87 Martinez at Selby Smelter 88 Martinez at Lower Lake, Lake County, California 89 Transitionary Beds of Gabb 89 Stanton's Discussion of the Fauna 91 Stratigraphy and Structure 92 Fauna of Martinez at Lower Lake 95 Martinez of San Mateo County 99 Eocene(?) of the Santa Cruz Quadrangle 102 Summary of Martinez Stratigraphy 103 •«'«,•« 4 • » I . . I » •• £ * ' *t r« - • •» • • . • * * *. . • * •*>•*••>•>• i •.,•»*.-•'«• 62 University of California Publications in Geology [VOL. 8 PAGE Summary of Martinez Fauna 106 Suggestion of Fauna as to Climate during Martinez Time Ill Eelationship of Chico and Martinez Faunas 112 Faunal Eelationship of the Martinez to the Tejon 112 Comparison of Uppermost Martinez and Lowermost Tejon 114 Time-Interval between Deposition of Martinez and Tejon 117 Correlation of Martinez with Eocene of the Atlantic and Gulf States 117 Genera Common to Martinez and Midway 118 General Present in Midway but Absent in Martinez 119 Proposed Correlation 119 Summary 120 Descriptions of Species , 120 Anthozoa 120 Flabellum, sp 120 Paracyathus( ?), sp 120 Echinoidea 121 Cidaris(f), sp., a 121 Cidaris, sp., c 121 Schizaster lecontei Merriam 121 Bryozoa 122 Membranopora( ?), sp 122 Brachiopoda 122 Ehynconella( ?), sp 122 Pelecypoda 123 Leda packardi, n. sp 123 Leda milleri, n. sp 123 Yoldia gesteri, n. sp 124 Yoldia powersi, n. sp 124 Pinna barrowsi, n. sp 125 Lima(?) claytonensis, n. sp 126 Lima(?) haseltinei, n. sp 126 Ostrea buwaldana, n. sp 127 Ostrea weaveri, n. sp 127 Pecten (Chalamys?), sp 128 Modiolus bakeri, n. sp 128 Cuspidaria hannibali, n. sp 129 Crassatellites studleyi, n. sp 129 Crassatellites stewartvillensis, n. sp 130 Crassatellites claytonensis, n. sp 131 Cardita veneriformis Gabb 131 Phacoides quadrata, n. sp 131 Phacoides muirensis, n. sp 132 Phacoides diaboli, n. sp 132 1914] Dickerson: Fauna of the Martinez Eocene of California 63 PAGE Dosinia(?) lawsoni, n. sp 133 Venus( f ), sp ...^...~ 133 Meretrix stantoni, n. sp 134 Meretrix dalli, n. sp 135 Meretrix, sp 135 Macrocallista(?) packi, n. sp 136 Paphia(?) clarki, n. sp 136 Tellina herndonensis, n. sp 136 Tellina packardi, n. sp 137 Tellina perrini, n. sp 137 Tellina kewi, n. sp 138 Psammobia(?) cylindrica, n. sp 139 Spisula(?) weaveri, n. sp. Packard 139 Martesia(?), sp 140 Gastropoda 140 Acmaea martinezensis, n. sp 140 Fissurella(?) behri, n. sp 141 Nerita(?) biangulata, n. sp 141 Natica (Gyrodes) lineata, n. sp 141 Amauropsis martinezensis, n. sp 142 Turritella clarki, n. sp 142 Cerithium, sp 143 Alaria, sp 143 Anchura englishi, n. sp 144 Anchura gabbi, n. sp 144 Seraphs (?) thompsoni, n. sp 144 Ovula martini, n. sp 145 Tritonium buwaldi, n. sp 145 Tritonium martinezensis, n. sp 146 Hemifusus(?) waringi, n. sp 146 Fusus dumblei, n. sp 146 Olivella claytonensis, n. sp 147 Turris louderbaeki, n. sp 147 Surcula merriami, n. sp 148 Surcula fairbanksi, n. sp 148 Surcula (Surculites) andersoni, n. sp 149 Surcula, sp 149 Cephalopoda 150 Hercoglossa merriami, n. sp 150 Nautilus stephensoni, n. sp 150 Previously Described Martinez Species Ke-figured 151 Appendix: List of Localities .. 152 64 University of California Publications in Geology [VOL. 8 INTRODUCTION The discovery of several new areas of Martinez rocks and the secur- ing of large additions to the fauna in them have led to further investi- gation of the stratigraphy and fauna of the lower Eocene of the Pacific Coast. That the Martinez is separated from the Chico (Cretaceous) below and from the Tejon (upper Eocene) above by well-marked unconformities are the principal conclusions from stratigraphic studies. Faunal studies prove that the Martinez fauna of approxi- mately two hundred species is quite distinct from the Chico and the Tejon faunas. The great increase in the fauna makes correlation with the lowermost Eocene of the Gulf and Atlantic states more certain. The proposed correlation made in this paper fixes a portion of the Martinez as the equivalent of the lowermost Eocene of the Gulf States, the Midway, and the rest as the representative of an earlier Eocene time than has been recognized elsewhere in the United States. REVIEW OF THE LITERATURE W. M. Gabb1 first used the term Martinez Group to describe strata which he thought were transitional between the Chico-Cretaceous and his Cretaceous "B," the Tejon of the present nomenclature. Dr. T. W. Stanton2 next investigated this group. He proved that a portion of the Martinez Group of Gabb was Chico and placed the upper portion as a distinct faunal zone of the Tejon, designating it as lower Tejon. Dr. Stanton 's admirable review was followed by a short, decisive paper by Merriam3 who worked at the type locality. Merriam described the conditions at the type locality as follows : In the following discussion the name Martinez is applied to that portion of Gabb's Martinez Group which remains, after the removal of the Chico- Cretaceous element. The writer's statements are based on observations, extend- ing over a period of several years, made in the typical region for the group, viz., that adjacent to the town of Martinez. In the hills to the southwest of Martinez, strata of unquestionable Chico age, containing a characteristic fauna, occur over a considerable area. In a 1 Gabb, W. M., Kept. Geol. Surv. of California, Palaeontology, vol. 2, p. 13 of preface, 1869. 2 Stanton, T. W., The Faunal Relations of the Eocene and Upper Cretaceous on the Pacific Coast, 17th Ann. Kept. U. S. Geol. Surv., pp. 1011-1060, 1895-6. s Merriam, J. C., The Geological Relations of the Martinez Group of Cali- fornia at the Typical Locality, Jour, of Geology, vol. 5, pp. 767-775, 1897. 1914] Dickerson: Fauna of the Martinez Eocene of California 65 • fine outcrop of compact bluish sandstone occurring on the west side of Alhambra Valley, and near the top of the Chico, the writer found an abundance of fossils, characteristic of this group. . . . From this point to the east and west the structure of the strata is anticlinal, showing an apparently conformable series up as far as the Miocene on each side. From the standpoint of stratigraphy, one would hardly be disposed to find fault with Gabb 's conception of the Martinez, since in this, the typical locality, the Chico, Martinez, and Tejon appear everywhere to be conformable, while numerous complications of the stratigraphy have still farther increased the difficulty of separating these three groups on stratigraphic grounds. Lithologically there are some differences between the Martinez and the adjoining formations, the most important of which are the slightly different aspect of its sandstones and the frequent presence in them of considerable quantities of glauconite. The sandstones are often grayish, differing from the yellowish or bluish rocks of the Chico and the massive white to dull red Tejon sandstones. In many places the Martinez contains large quantities of glauconite disseminated evenly through the sandstone in rounded grains of considerable size. Glauconite does not seem to occur at all in the Chico but may possibly be found toward the base of the true Tejon. The truly glauconitic rocks belong principally to the Martinez. While the group shows little which would serve to separate it strati- graphically or lithologically from the over and underlying formations, its fauna, on which Gabb based his classification, contains numerous elements throwing light on its geologic relations. Between the Chico-Cretaceous and the Miocene there are two distant faunas present, viz., the Martinez (in part) and Tejon of Gabb, or the Lower and Upper Tejon of Mr. Stanton. As other criteria failed to separate satisfactorily the Chico, Martinez, and Tejon, exten- sive fossil collections were made by the writer at all possible points. Merriam then discussed collections made in a section across the strike in the typical Chico, Martinez and Tejon, suggested the exist- ence of two faunal zones in the Martinez, and described the palaeon- tology of the Martinez : The faunas, though overlapping, are in the main quite distinct, and no great difficulty has been experienced by the writer in separating the groups on this basis. While some intermingling of species exists, it is not greater than we should expect to find in adjoining groups or periods. It should also be observed that the beds with a Tejon-like Martinez fauna and those containing an assemblage of characteristic Tejon forms are comparatively close together. The change from one fauna to the other may possibly have taken place in a short time by migration, but we can not assert positively as yet that the apparent conformity of the beds is a real one; sedimentation may have been interrupted between the times of deposition of the two groups. It is, at any rate, quite clear that the two sets of strata, or two faunas, while belonging perhaps to the same series, represent different periods in the geological history of California, periods quite as distinct, so far as faunal evidence is concerned, as the Miocene and Pliocene, or the Pliocene and Quaternary. The upper division of this series has already, on the grounds of its characteristic fauna, been named the Tejon. To a mixed group of rocks, to which the fauna here called the Martinez gave individuality, the name Martinez group was applied 66 University of California Publications in Geology [VOL. 8 by Gabb. It seems desirable, after having cut out the Chico portion of Gabb's Martinez which was probably not the one on which he based the group, to apply the name used by him to the distinct fauna or group which remains. As to the nomenclature of the supposedly conformable series, including the Martinez and Tejon, it seems best to apply to it for the present the term Martinez-Tejon series, though future convenience may demand a special series name. To apply the name Tejon to the whole series would be to modify con- siderably the meaning of this term as used originally, and would have besides the fault of taking the name from a smaller division to apply it to a larger, leaving the first to be virtually renamed. He then closed with a definition of the Martinez Group as follows : The Martinez group, comprising in the typical locality between one and two thousand feet of sandstones, shales, and glauconitic sands, forms the lower part of a presumably conformable series, the upper portion of which is formed by the Tejon. It contains a known fauna of over sixty species, of which the greater portion is peculiar to itself. A number of its species range up into the Tejon and a very few long-lived forms are known to occur also in the Chico. Since the Martinez and Chico are faunally only distantly related, it is probable that an unconformity exists between them. Though satisfactory correlation of California formations with the subdivisions of the standard geological scale can be accomplished only when the local scale is fully worked out, we may, for the present at least, accept Mr. Stanton's correlation of the Martinez with a portion of the Eocene. In a general correlation paper, Dall4 places both the Martinez and the Tejon as correlative of the Midway stage of the southeastern United States and the Cernaysian of Europe. Lawson5 in describing a section in the neighborhood of the type locality of the Martinez substitutes the name "Karquinez series" for that of Merriam's Martinez-Tejon series, and estimates their combined thickness as 4300 feet. In a paper entitled " Contribution to the Palaeontology of the Martinez Group," Weaver6 carefully described the distribution of the Martinez, its stratigraphic relations, recognized two faunal zones, correlated it with the Midway of the Gulf States and the Aquia stage of Maryland and Virginia, and described several new species. In summary he said : .... the Martinez represents a distinct division of time in the geological history of California. It contains a fauna distinct from both the Chico and * Dall, W. H., A Table of the North American Tertiary Horizons correlated with one another and with those of western Europe, 18th Ann. Eept. U. S. Geol. Surv., part 2, pp. 327-348, 1898. s Lawson, A. C., A Geological Section of the Middle Coast Eanges of Cali- fornia, Science, n.s., vol. 15, p. 416, 1902. « Weaver, C. E., Contribution to the Palaeontology of the Martinez Group, Univ. Calif. Publ. Bull. Dept. Geol., vol. 4, pp. 101-123, 1905. 1914] Dickerson: Fauna of the Martinez Eocene of Calif ornia 67 the Tejon. On the average it is composed of about two thousand feet of thick-bedded sandstones and conglomerates. Its geographical extent as at present known is confined to southern Lake County and a belt extending north and south across Carquinez Strait. Its position in the geologj,caj_ scale seems to correspond most closely to a portion or all of the lower quarter of the Eocene. Arnold7 gave a list of fossils compiled from the papers of Stanton, Merriam, and Weaver, added a few new species obtained "from a locality of doubtful Martinez age," and described Pecten proavus from this locality in Santa Cruz County. He mentioned Rock Creek, Los Angeles County as a Martinez locality. In a later paper8 he described the Santa Cruz locality, gave a list of fossils obtained from it and described Cidaris merriami, Semele gayi, Tritonium newsomi, Hipponyx carpenteri, Patella mateoensis, and Fissurella perrini. He described the Martinez (?) of the Santa Cruz Quadrangle as follows : The diabase dike exposed north of the headwaters of Pescadero Creek has brought up considerable inclusions of impure limestone which, from the fossils found in them, appear to be of Eocene age. Obviously the stratigraphic rela- tions of this great limestone inclusion are unknown, but the fossils indicate its Eocene age and that it probably belongs in the lower part of the formation. The following fauna occurs in this limestone: LIST OF LOWER EOCENE FOSSILS FROM THE SANTA CRUZ QUADRANGLE ECHINOIDEA Cidaris merriami, new species BRACHIOPODA Terebratalia, new species, m. Terebratulina tejonensis Stanton Terebratalia, new species, p. PELECYPODA Pecten proavus Arnold Semele gayi Arnold GASTROPODA Chlorostoma, new species, c. Patella, new species, b. Cylindrites ~brevis(?) Gabb Patella mateoensis Arnold Fissurella perrini Arnold Thylacodes, new species, w. Hipponyx carpenteri Arnold Tritonium newsomi Arnold Odostomia, new species, b. 7 Arnold, Kalph, The Tertiary and Quaternary Pectens of California, Profes- sional Paper no. 47, U. S. Geological Survey, pp. 11-12, 1906. s Arnold, Ealph, Descriptions of New Cretaceous and Tertiary Fossils from the Santa Cruz Mountains, California, Proceedings of the United States National Museum, vol. 34, no. 1617, pp. 347, 359-363, August, 1908. 68 University of California Publications in Geology [VOL. 8 A short description of these same beds is also given in the Santa Cruz folio :9 The diabase exposed north of the headwaters of Pescadero Creek has brought up some considerable inclusions of impure limestone which, from the fossils found in them, appear to be of Eocene age. The limestone is light brown in color, usually rather soft except where silicification has begun, and appears to be made up of broken marine shells, a little argillaceous material, and small fragments of what may be tuff. The thickness of the limestone is nowhere more than 100 or 200 feet. On Langley and Mindego Hills, two and a half miles northeast and south- east, respectively, of the village of La Honda, are two other small areas of calcareous sandstone, supposed to be of the same age as that exposed north of the headwaters of Pescadero Creek. Fossils — The fauna of the limestone in the Pescadero Creek exposure above referred to is different from that of any of the other known formations of California. Some of its species as Patella mateoensis Arnold, Fissurella perrini Arnold, Tritonium newsomi Arnold, and Pecten proavus Arnold, are closely allied to Chico (Cretaceous) forms, while Ostrea cf. idriaensis Gabb is found only in the Tejon (middle Eocene), and Terebratulina tejonensis Stanton only in the Martinez (lower Eocene). In view of the affinities of the above species and also of the several new ones, it appears probable that the fauna represents either a new horizon of the lower Eocene or a local development of the Martinez (lower Eocene) fauna. These beds do not appear to be of Martinez age to the writer. Dickerson10 in a short paper described unconformities between the Martinez and Chico and between the Tejon and Martinez, and gave partial lists of fossils collected from a section across the strike from the Chico, Martinez and Tejon. These lists show a very marked difference between the faunas of the Chico, Martinez and Tejon. In a recent number of the Journal of Geology, Durable11 described an unconformity between the Cretaceous and beds which he supposed to be of Martinez age. Later work by Taff, Gester, Parsons, and Dickerson has shown that the so-called Martinez is Tejon. » Branner J. C., Newsom, J. E., Arnold, E., Santa Cruz Folio, No. 165, U. S. Geological Survey, p. 3, April, 1908. 10 Dickerson, Eoy E., The Stratigraphy and Faunal Relations of the Martinez Formation to the Chico and Tejon North of Mount Diablo, Univ. Calif. Publ. Bull. Dept. Geol., vol. 4, pp. 173-177, 1911. 11 Durable, E. T., Notes on Tertiary Deposits near Coalinga Oil Field and their Stratigraphic Eelations with Upper Cretaceous, Jour. Geol., vol. 20, pp. 28-37, 1912. 1914] Dickerson: Fauna of the Martinez Eocene of California 69 AEEAL DISTRIBUTION OF THE MARTINEZ IN CALIFORNIA PRINCIPAL LOCALITIES The most northerly occurrence of Martinez thus far reported is near the town of Lower Lake, in Lake County. Martinez strata occur in the Napa Quadrangle four miles northwest of Suisun, where Gabb12 found fine specimens of Turrit ella pachecoensis and Meretrix(f) fragilis, and near Benicia. Across the Carquinez Strait from Benicia is the type locality of the Martinez near the town of that name. In 1909, R. W. Pack and G. E. Gester recognized a small area of Martinez on Carquinez Strait at Selby Station. North of Mount Diablo another area occurs, and a very small but interesting locality was found south- west of Mount Diablo by the 1911 University of California Summer Session class in palaeontology. Beds of Martinez age make up a portion of the strata at San Pedro Point, in San Mateo County. Dumble13 reported Martinez north of Coalinga, but later work has shown that these beds are a phase of the Tejon. A typical collection of Martinez fossils was made by the 1910 Stanford University class in geology forty miles northwest of Los Angeles in the Calabassas Quadrangle. Arnold14 reported Martinez at Rock Creek, Los Angeles County. The Martinez was recognized by the 1913 University of California Summer Session class in palaeon- tology in the Santa Ana Mountains. No positive evidence of Martinez south of this last point is known, but Stanton15 reports Glycimeris veatchii var. major from Point Loma near San Diego. None of the collections from this locality which the writer has examined have con- tained any typical Martinez forms; all appear to be Tejon or Chico. DISTRIBUTION OF THE MARTINEZ COMPARED WITH THAT OF THE TEJON Some interesting relations between the Martinez and the Tejon are brought out when their distribution is studied. (See fig. 1.) In certain localities the Martinez and Tejon occur together, but in other i^ Gabb., W. M., Kept. Geol. Surv. of California, Palaeontology, vol. 2, p. 135, 1869. is Dumble, E. T., Notes on Tertiary Deposits near Coalinga Oil Field and their Stratigraphic Eelations with Upper Cretaceous, Jour. Geol., vol. 20, pp. 28-37, 1912. i* Arnold, E., Tertiary and Quaternary Pectens of California, Professional Paper no. 47, U. S. Geological Survey, p. 11, 1906. is Stanton, T. W., The Faunal Eelations of the Eocene and Upper Cretaceous on the Pacific Coast, 17th Ann. Eept. U. S. Geol. Surv., p. 1040, 1895-6. 70 University of California Publications in Geology [VOL. 8 places the one occurs without the other. They are associated at Lower Lake in Lake County, but no Martinez occurs at the Marys- ville Buttes in Colusa County where uppermost Tejon is found. The Tejon of Merced Falls rests directly upon rocks of Jurassic age. Both are found at Benicia, Martinez, and north of Mount Diablo, but on the south side of Mount Diablo, the Tejon for the most part rests directly upon the Chico. At San Pedro Point, San Mateo County, Martinez without Tejon is found. At the type locality of the Tejon on the Canada de las Uvas the upper Eocene rests upon the basement complex of the Tehachapi Mountains, and no Martinez appears to be present at the southern end of the San Joaquin Valley. However, Martinez does occur on the seaward side of the ranges along the coast thirty miles south of this same latitude in the Calabasas Quadrangle. The Tejon at San Diego overlies the Chico. Fairbanks10 mapped no Eocene in the San Luis Quadrangle. South of this quadrangle great thicknesses of Eocene strata were reported by Eldridge and Arnold17 in the Santa Clara Valley. These beds were called the Topatopa formation. No attempt was made to differentiate the upper and lower portions of the "formation." At least three marked epirogenic movements occurred during Eocene time: (1) a subsidence of the coast during which the Martinez sediments were deposited, (2) an uplift during which large portions of Martinez sediments were removed, (3) a subsidence during which the Tejon sediments were deposited. That the sea during the first subsidence did not extend so far inland as during the second appears to be true, and deposition by a transgressing sea might account for the occurrence of Tejon at Merced Falls and the Marysville Buttes unassociated with Martinez if it were not for a widespread uncon- formity between these two groups. Tejon sediments 2600 feet thick south of Mount Diablo rest unconformably upon Chico, whereas at least 700 feet of Martinez is found between the groups north of the mountain. Unconformity between the two groups and a more widely spread sea during Tejon time account for the difference in distribution of the Martinez and Tejon in California. 16 Fairbanks, H. W., San Luis Folio, no. 101, U. S. Geological Survey, p. 3, 1904. i? Eldridge, G. H., and Arnold, E., The Santa Clara Valley, Puente Hills and Los Angeles Oil District, Southern California, Bull. no. 309, U. S. Geological Survey, pp. 5-7, 1907. Fig. 1. Map of California showing probable extent of the Tejon and Martinez Seas, vhich in general is the more easterly marks the maximum inland extension of the Tejon Se )ther line indicates the probable easterly limit of the Martinez Sea. 1, Tejon of Round Valley, Mendocino County; 2, Tejon near Oroville; 3, Tejon of Marysville Buttes; louth of Merced River Canon; 5, Tejon of the Tehachapi Mountains; 6, Martinez of Rock Creek; 7, Tejon o !ounty; 8, Tejon and Martinez at Clear Lake; 9, Martinez north of Suisun ; 10, Martinez and Tejon at Benic >cality of Martinez; 12, Martinez and Tejon north of Mount Diablo; 13, Martinez and Tejon south of Me 4, Martinez of San Pedro Point, San Mateo County; 15, Tejon at New Idria; 16, Tejon at Coalinga Distric 1914] Dickerson: Fauna of the Martinez Eocene of California 71 DESCRIPTIONS OF THE TYPICAL MARTINEZ SECTIONS IN CALIFORNIA • LOWER AND MIDDLE ZONES OF MARTINEZ NORTH OF MOUNT DIABLO The stratigraphy and the faunal relations of the Martinez to the Chico and Tejon have already been fully discussed in a former paper.18 The zonal relations of the Martinez in this area have not been described. In the Martinez area four miles north of Mount Diablo we have a lower section which has yielded the most abundant fauna of any Martinez locality, over eighty species having been found in the lowermost beds alone. Abundantly fossiliferous, distinctly bedded outcrops extending for the entire length of the east-west four- mile strip have enabled the writer to be sure of the stratigraphic position of the various fossil localities. A north-south cross-section examined a mile south of Stewartville is, in descending order, as follows : (5) Gray-green shales, 250-300 feet. (4) Gray-green, glauconitic sandstone, 50 feet. (3) Fine-grained, hard, gray sandstone, 200 feet. (2) Shales and argillaceous sandstones, 100 feet. (1) Brown, conglomeratic, lower sandstone, 50-100 feet. Total, 650-750 feet. (See figure 2.) A similar section was examined at the head of Oil Creek, two miles west of this line. The principal fossil localities are limited to the lower bed and the gray-green glauconitic sandstone four hundred feet above the base. The accompanying map shows these localities (see fig. 3). The lower bed yielded a fauna in which one of the most abundant forms was Meretrix dalli, n. sp. FAUNA OF THE MERETRIX DALLI ZONE Large collections from the lowermost beds have been made by J. R. Powers, B. L. Clark, William Kew and the writer in the past three years. Below is a complete list of the fauna obtained from these beds: is Dickerson, Roy E., Univ. Calif. Publ. Bull. Dept. Geol., vol. 6, pp. 173-177, 1911. 72 University of California Publications in Geology [VOL. 8 .o ~ o •a 03 .3 fl •e.2 Is ^3 «H Oco . J 70C (8) Gray shales and thin bedded sandstones 1 (7) Massive, tan sandstone L 1600 Martinez (6) Trochocyathus zitteli beds J Eocene (5) Massive, tan sandstone ) (4) Fine-grained, massive, tan sandstone f (3) Medium-grained, gray, sandstone 500 (2) Meretrix dalli beds ) (1) Medium-grained, gray sandstone C Total 4000 IV. SECTION NEAR MARTINEZ AT TYPE LOCALITY Feet (7) Solen stantoni beds 1 (6) Gray sandstone I 1000 (5) Gray-green, glauconitic sandstone J (4) Trochocyathus zitteli beds ) Martinez , Har(J / gandstone 300 Eocene (3) Gray-green, glauconitic sandstone | Trochocyathus zitteli beds j (2) Gray sandstone with lenses of limestone 300 (1) Conglomerate 50 Total 1700 V. SECTION NEAR SELBY SMELTER, CARQUINEZ STRAITS Feet C (3) Gray-green, foraminiferal shale 500 ;ZJ (2) Trochocyathus zitteli beds ) [ (1) Gray-green, glauconitic sandstone J Total .. 700 3 OTQ' Cb VJ 06 NJ 106 University of California Publications in Geology [VOL. 8 VI. SECTION NORTH OF MOUNT DIABLO Martinez Eocene Feet 300 (5) Gray-green shale (4) Gray-green, glauconitic sandstone 1 Trochocyathus zitteli beds ( (3) Fine-grained, gray sandstone 200 (2) Shales and sandstones 100 (1) Brown, conglomeritic sandstone Meretrix dalli beds ... 50 Total .. 700 SUMMARY OF MARTINEZ FAUNA The table given below indicates the occurrence and distribution of the forms which are found in the Martinez. The local occurrence of each species is given in the first major column and the range of the species is indicated in the second. Three major faunal zones are recognized in the Martinez : a lower, the Meretrix dalli zone ; a middle, the Trochocyathus zitteli zone ; and an upper, the Solen stantoni zone. The Meretrix dalli zone is typically represented in the Martinez north of Mount Diablo, while the Trochocyathus zitteli and the Solen stan- toni zones were first recognized at the type locality near Martinez. The type locality may be regarded as the type locality of these last two zones as well. The sections given above refer to their respective columns in figure 5. LIST OF MARTINEZ SPECIES MARTINEZ LOCALITIES RANGE OF SPECIES Anomalina ammonoides Reuss Martinez N. of 1 Mount Diablo Type locality, * Benicia, Selby m « J3 •g g S si h ? to g 0 N te C o §.„ «"3 x J{ 1 Stylophora( ?), sp. X x Flabellum remondianum Gabb X X X .... X? X X x Flabellum. sp. x x Paracyathus( ?), sp X x Trochocyathus zitteli (Merriam) X X x Schizaster lecontei Merriam X x X XXX x Cidaris(?), sp., c X x Cidaris(f), sp., a X x x X CidarisC?), sp., d ... X X 1914] Dickerson: Fauna of the Martinez Eocene of California 107 LIST OF MARTINEZ SPECIES — (Continued) MARTINEZ LOCALITIES RANGE OF SPECIES >»1 |i IS Is ! i i§ li ll 3g «.s II ' II O c8 O c; 'o S *-« +* 1! J Bhynconella(?), sp x X .... Terebratulina tejonensis Stanton x X x .... Membranipora, sp X X .... Avicula cf. pellucida Gabb x X .... Anatina(?), sp X X .... .... Astarte(f), sp X X Cardium cooperi Gabb X X XXX X .... Cardium cf. cooperi Gabb X X X X X x Cardita veneriformis Gabb X x .... Cucullaea mathewsonii Gabb X X X X X X .... Cucullaea cf. mathewsonii Gabb X .... .... Corbula, sp., a X x .... Crassatellites grandis (Gabb) X X? .... X .... X X .... Crassatellites claytonensis, n. sp. X X .... Crassatellites unioides (Stanton) X X x x x Crassatellites stewartvillensis, n. sp... X x .... Crassatellites sp a x Crassatellites studleyi, n. sp X X .... .... Dosinia(^) lawsoni n sp x x x Glycimeris veatchii, var. major Stanton X X X X X X? Glycimeris cf. veatchii var. major Stanton x x Leda gabbi Conrad X X X .... XXX x .... Leda alaeformis (Gabb) X X X X X Leda packardi, n. sp X X X X X .... Leda cf packardi n sp x Leda milleri, n. sp X X .... Lima multiradiata Gabb X X X X .... Lima cf. multiradiata Gabb X X? .... Lima(?) haseltinei, n. sp X X .... Lima(?) claytonensis, n. sp X x .... Meretrix stantoni, n. sp X X X? X .... Meretrix dalli, n. sp X X X Meretrix cf. stantoni, n. sp X x .... Meretrix, sp., a X x x .... Meretrix, sp., & .. x Mactra(?) tenuissima Gabb X X X X Modiolus ornatus (Gabb) X X X .... XXX X .... Modiolus merriami (Weaver) X XXX .... .... Modiolus bakeri, n. sp X X x x .... Modiolus, sp. indet. x Modiolus, sp. indet ... X 108 University of California Publications in Geology [VOL. 8 LIST OF MARTINEZ SPECIES — (Continued) MARTINEZ LOCALITIES RANGE OF SPECIES °l Si | o to J3 i "S ® SO 8" -a 1 •^ rt O O ^ CH .— £3 "^ ° v PH-^ C rH N J3 • — **•* N O £ p g.~ §3 £s .« ?»» W 0 03 0 9> E-ipQ H GOPn EH •3 g gg w-3 J3 Martesia(f), sp X X Macrocallista(?) packi, n. sp X X x Mytilus cf ascia Gabb x Neaera dolabraeformis Gabb x X X? X X Neaera hannibali, n. sp X x Nucula (Acila) truncata Gabb x X X .... X Nucula (Acila), sp x x Ostrea, sp x x Ostrea weaveri, n. sp X X x? Ostrea buwaldana, n. sp X X x Ostrea appressa Gabb x Paphia(?) clarki, n. sp x x X Paphia, sp., a x Pecten, sp X Pecten interradiatus Gabb X X X Pecten, sp. . x Perna, sp x Pholadomya nasuta Gabb x X X XXX Pinna barrowsi, n. sp X x Phacoides muirensis, n. sp X X Phacoides quadrata, n. sp x x Phacoides diaboli, n. sp.* Phacoides, sp x Phacoides turneri (Stanton) x X X X X Phacoides, sp x X Plicatula ostreaf ormis Stanton X . . Psammobia(?) cylindrica, n. sp X X x Psammobia hornii (Gabb) X X .... X XXX Solen parallelus Gabb(?) X .... X Solen, sp x X X Solen stantoni Weaver x x x X .... X Spisula(?) weaveri, n. sp. Packard.... x X Tapes(?) quadrata Gabb x X .... X X X X Tapes cf. quadrata Gabb x Tellina(?) undulifera Gabb x X X XXX Tellina kewi, n. sp X X X X Tellina packardi, n. sp X X Tellina herndonensis, n. sp X X Tellina cf. parilis Gabb x X Tellina sp a x Tellina sp b x Tellina aequalis Gabb x X X .... X? X X Tellina perrini, n. sp X X Teredo, sp x X .... X X X 1914] Dickerson : Fauna of the Martinez Eocene of California 109 LIST OP MARTINEZ SPECIES — (Continued} MARTINEZ LOCALITIES RANGE OF SPECIES •So *t ~r > |S 13 * "~! ° a3 I ll 11 *a § g* -S- !•- § Is 31 3 i'o *5? "3 '3 °:§ a)-3 !3 S-3 0 Venus(?), sp X Venericardia planicosta Lamarck X .... X? .... X? X Yoldia(?) powersi, n. sp x X Yoldia gesteri, n. sp X X Zirphaea(f), sp x X Dentalium cooperi Gabb x X X X X X X X X Dentalium stramineum Gabb x X X XXX X X Acmaea martinezensis, n. sp X X Alaria, sp X Ampullina cf. striata Gabb X x .... Ampullina striata Gabb x X X Amauropsis(?), sp X Amauropsis martinezensis, n. sp x X X x X Anchura englishi, n. sp X X Anchura, sp x X Anchura gabbi, n. sp x X Architectonica tuberculata Weaver X .... - .... x Architectonica sp. x Actaeon lawsoni Weaver X x Bullinula subglobosa \Veaver x x Brachysphingus liratus Gabb x X X X? X X X Brachysphingus sinuatus Gabb x Chlorostoma( ?), sp. x Cylichna costata Gabb x X X X X X X X X Cassidaria tuberculata (Gabb) X? .... X .... X? Cerithiopsis alternata Gabb X x X Cypraea bayerquei Gabb X X X Cerithium, sp. . X x Discohelix sp tt x x Discohelix californicus Weaver X X Ficopsis, sp x X X X Fissurella(?) behri, n. sp X X Fusus aequilateralis Weaver X X X Fusus(?), sp., a X X Fusus occidentalis Gabb X X .... Fusus flexuosus Gabb X X Fusus cf. mathewsonii Gabb X X Fusus mathewsonii Gabb x X XXX X Fusus aratus Gabb X X Fusus martinez Gabb X X .... X Fusus(?), sp., & x X Fusus dumblei, n. sp X X Fusus cf. martinez x X Fusus, sp., d x X 110 University of California Publications in Geology [VOL. 8 LIST OF MARTINEZ SPECIES — (Continued) MARTINEZ LOCALITIES RANGE OF SPECIES Fususf?} sp. Martinez N. of *\ ^ Mount Diablo Type locality, Benicia, Selby 3 ! L Is I! 0 03 '3 '57 *o 9 2^ i-5 CCPk E-< 02 .8 EH '3 Meretrix < dalli zone Chico Galerus excentricus Gabb X XXX X X Heteroterma gabbi Stanton X x Heteroterma trochoidea Gabb X x x Heteroterma striata Stanton X x x x Heteroterma, sp. indet X X .— X x Hemifusus(?) waringi, n. sp X HipponyxC ?), sp. x Lunatia hornii Gabb x X X .... X X x Lunatia cf. nuciformis Gabb X .... X x Lunatia, sp. a, x Megistostoma striata Gabb(?) X? X X? Neptunea mucronata Gabb x X x X Neptunea (Tritonofusus) cretacea, Gabb x x Neptunea, sp., a X Natica (Gyrodes) lineata, n. sp x X X Natica, sp., a x x Natica, sp., & .... x Natica, sp., c x Natica, sp., e x Naticina, sp. x x Nerita biangulata, n. sp. x X Niso polito Gabb x X X Ovula martini, n. sp. x x x X Olivella claytonensis, n. sp. x x Perissolax tricarnatus Weaver x x X .... XXX X Patella, sp. x Patella sp x Ringinella pinguis Gabb x x X X X Surcula merriami, n. sp. x X Surcula (Surculites) inconspicua Gabb x x Surcula fairbanksi n sp x x Surcula (Surculites) andersoni, n. sp. Surcula sp x x X Siphonalia(?) lineata Stanton x x x x x X Strepsidura pachecoensis Stanton x x Spirocrl vphus ( ? ) SP x Seraphs (?) thompsoni, n sp x . .. X Turbinella crassatesta Gabb x x Turritella martinezensis Gabb x X X Turritella cf martinezensis Gabb x Turritella pachecoensis Stanton Turritella cf. pachecoensis Stanton ... X X x x X X 1914] Dickerson: Fauna of the Martinez Eocene of California 111 LIST OF MARTINEZ SPECIES — (Continued') MARTINEZ LOCALITIES RANGE OF SPECIES ^3 £| « ^i c3 ^3 QO ^ o A ta^ I5 §-• * i is SI .«§ 3 8 "^2 ® ^ •*• « N o h & Q/3 i ac o E~< «"» 2s ° M^ Rj o 1? '5? "3 g 2S .s-s S S^ HPQ hJ CQPn EH 022 EH'N S'O O Turritella infragranulata Gabb ... XXX .... .... XXX Turritella conica Weaver x x? x? Turritella clarki, n. sp. x x Turris, sp., a x Turris claytonensis Gabb* X . . Turris sp indet x Tritonium martinezensis, n. sp. ... X X X Tritonium, sp., a x Tritonium buwaldi, n. sp X X Tritonium(?), sp X X Tritonium pulchrum Weaver x . . x Tritonium, sp x Urosyca caudata Gabb XXX XXX Urosyca robusta Weaver X X X X Xenophora zitteli Weaver X X X X Aturia mathewsonii Gabb* x Hercoglossa merriami, n. sp X X Nautilus stephensoni, n. sp X X Crustacean remains x Shark tooth X X X X Leaf X — • Fossil wood * South of Mount Diablo. SUGGESTION OF FAUNA AS TO CLIMATE DURING MARTINEZ TIME The collections from strata of Martinez age contain the genera Cypraea, Ovula, Aturia, Turris, and Surcula, which are represented mainly by tropical or subtropical species in the ocean of the present time. Several genera which are now represented by boreal or tem- perate species are found in this fauna as well. This evidence seems to indicate that the climate of Martinez time was decidedly milder than that of the Recent period in these latitudes. The mixture of subtropical and boreal forms indicates a warm temperate climate. Practically none of the genera mentioned above -occur in the Chico, and an absence of other tropical or subtropical genera from the uppermost Cretaceous shows some change in climate between Chico and Martinez times. Tejon climate, however, was decidedly warmer 112 University of California Publications in Geology [VOL. 8 than that of the Martinez, judging from the much greater abundance of tropical forms represented in its fauna. For a discussion of the Tejon climate the reader is referred to a recent paper by the writer27 on the Eocene of the Marysville Buttes. RELATIONSHIP OF THE CHICO AND MARTINEZ FAUNAS The check-list given above shows that the following Chico species range upward into the Martinez: Nucula truncata Gabb, Cylichna costata Gabb, Dentalium cooperi Gabb, Dentalium stramineum Gabb. All of these species appear practically identical with those of the Chico, but unfortunately they represent genera whose species are usually very persistent. Tellina cf . parilis Gabb which was found near Lower Lake is nearly identical, as far as external form is concerned, with T. parilis of the Chico. Meretrix(f) dalli, n. sp., is very similar to M. fragilis Gabb of the Chico. Glycimeris veatchii var. major (Stanton) is distinguishable from G. veatchi (Gabb) but it is evidently a descendant of the Chico form. Amauropsis martinezensis, n. sp., is allied to A. oviformis Gabb in the strata beneath. The Cretaceous genera Ringinella and Anchura, are represented by E. pinguis Gabb, A. englishi and A. gabbi, n. sp., respectively. This evidence indicates a much closer relationship between the Eocene and the Cretaceous than is generally found. FAUNAL RELATIONSHIP OF THE MARTINEZ TO THE TEJON The relationship between the Tejon and the Martinez is shown by the list given above. About twenty-five to thirty species range through portions of both groups. About fifteen to twenty of these range from the base of the Martinez to at least as high as the middle Tejon of the Mount Diablo region, and some of these extend even to uppermost Eocene at the Marysville Buttes. The following are species common to both the Martinez and the Tejon: Schizaster lecontei Merriam Leda gabbi Conrad Cardium cooperi Gabb Modiolus merriami (Weaver) Crassatellites grandis (Gabb) Modiolus ornatus (Gabb) *Cuspidaria dolabraef ormis (Gabb)(?) Nucula (Acila) cf. truncata Gabb * Described by Gabb from his Cretaceous B (= Tejon). 27 Dickerson, Koy E., Fauna of the Eocene at Marysville Buttes, California, Univ. Calif. Publ. Bull. Dept. Geol., vol. 7, p. 267, 1913. 1914] Dickerson: Fauna of the Martinez Eocene of California 113 fOstrea appressa Gabb(?) Pecten interradiatus Gabb Psammobia hornii (Gabb) fSolen parallelus Gabb Tapes (?)quadrata (Gabb) tVenericardia planicosta Lamarck ( ?) Cylichna costata Gabb Cerithiopsis alternata Gabb *Cuspidaria dolbraformis (Gabb) (?) Dentalium cooperi Gabb Dentalium stramineum Gabb Fusus martinez Gabb Fusus mathewsonii G&bk Galerus excentricus Gabb Lunatia hornii Gabb Niso polito Gabb Perissolax tricarnatus Weaver Aturia mathewsonii Gabb * Described by Gabb from his Cretaceous B (= Tejon). t Keported by Stanton from Lower Lake. Perissolax tricarnatus and Schizaster lecontei occur abundantly in the type section of the Tejon near Fort Tejon. Modiolus merriami was found in the Tejon on the south side of Pine Canon, Mount Diablo Quadrangle, by the Summer Session class in palaeontology. Flabellum remondianum is questionably reported from the Tejon. The following species were indeterminate : Avicula cf . pellucida Gabb, Megistostoma striata Gabb ( ? ) . The type specimen of Turritella conica Weaver appears very similar to a Turritella in the Tejon, but owing to the poor preservation of the type it is impossible to decide the point. Cassidaria tuber- culata (Gabb) is questionably reported from the Martinez at Benicia. The absence of the common Martinez species, such as Trochocyathus zitteli (Merriam), Cardita veneriformis Gabb, Cucullaea mathewsonii Gabb, Crassatellites unioides Stanton, Glycimeris veatchii, var. major (Stanton), Lucina turneri Stanton, Leda alaeformis (Gabb), Meretrix stantoni, n. sp., Pholadomya nasuta Gabb, Tellina undulifera Gabb, Ampullina striata Gabb, Amauropsis martinezensis, n. sp., Discohelix calif ornicus Weaver, Heteroterma gabbi Stanton, Heteroterma striata Stanton, Natica lineata, n. sp., Ringinella pinguis Gabb, Siphonalia(f) lineata Stanton, Turritella martinezensis Gabb, Turritella pachecoensis Gabb, Turritella infragranulata Gabb, and Urosyca caudata Gabb from an Eocene fauna is quite sufficient to make its Martinez age questionable. These species are excellent guide fossils because nearly any fossiliferous Martinez locality will yield at least three or four of them. Their range in many cases is through the entire Martinez, but so far as known none occurs in the Tejon or the Chico. A study of the list of Martinez species shows the absence of a great many typically Tejon species. Among the absent ones are : Cardium breweri Gabb, Cardita planicosta var. hornii (Gabb), Corbula parilis Gabb, 114 University of California Publications in Geology [VOL. 8 Dosinia elevata Gabb, Dosinia gyrata Gabb, Glycimeris sagittata Gabb, Meretrix hornii Gabb, Meretrix ovalis Gabb, Meretrix uvasana Gabb, Ostrea aviculaformis Anderson, Placunanomia inornata Gabb, Tapes conradiana Gabb, Tellina longa Gabb, Tellina remondii Gabb, Amau- ropsis alveata Gabb, Bulla hornii Gabb, Fusus californica Gabb, Rimella canalifera Gabb, Turritella merriami Dickerson, Turritella uvasana Conrad, Whitneya ficus Gabb. Many of these forms have a wide range in the Tejon, but so far as known they are not fo.und in the Martinez. There are many other Tejon forms which will serve as guides. The faunal break between the Martinez and the Tejon is very wide when we consider the large number of species which are confined to the one group or the other. i COMPARISON OF THE UPPEE MARTINEZ AND THE LOWERMOST TEJON During the last two Summer Sessions of the University the field classes in palaeontology made extensive collections in the Tejon, south of Mount Diablo. As was mentioned above in describing the small area of Martinez south of Mount Diablo, the Tejon for the most part is in unconformable contact with the Chico. Between Cave Point and Oyster Point a complete section of the Tejon was studied and it was found to be fossiliferous from top to botton. The basal portion in contact with the Chico was most prolific and yielded a very large fauna, a portion of which is given in the list below. This basal fauna was obtained from beds not over twenty-five feet above the bottom of the section. PARTIAL LIST OF SPECIES IN THE BASAL TEJON SOUTH OF MOUNT DIABLO Fungia(f), n. sp. Turbinolia(f), n. sp., a (long) Turbinolia(?), n. sp., b (short) Coral (reef form), sp. Cassidulus californicus Anderson Scutella, n. sp. Acila, sp. Astarte mathewsonii Gabb Avicula pellucida Gabb Cardium cooperi Gabb Cardium, sp. Corbula parilis Gabb Dosinia elevata Gabb Dosinia gyrata Gabb Glycimeris cf. sagittata (Gabb) Glycermis cor (Gabb) Leda gabbi Conrad Mactra, sp. Spisula, n. sp. Meretrix hornii Gabb Meretrix ovalis Gabb Meretrix uvasana Gabb Modiolus ornatus (Gabb) Ostrea aviculaformis Anderson Ostrea, sp. Phacoides, sp. Placunanomia inornata Gabb Psammobia hornii (Gabb) 1914] Dickerson: Fauna of the Martinez Eocene of California 115 PARTIAL LIST OF SPECIES IN THE BASAL TEJON SOUTH or MOUNT DIABLO — (Continued) PteriaC?), sp. Cassidaria tuberculata (Gabb) Solen parallelus Gabb Ficopsis remondii (Gabb) Tapes conradiana Gabb Fusus californica Gabb Tapes, sp. Fusus diaboli Gabb Tapes(f) quadrata Gabb Fusus martinez (Gabb) Tellina cf. aequalis(?) Gabb Fusus, sp. Tellina longa Gabb Galerus excentricus Gabb Tellina remondii Gabb Littorina compacta? Gabb Tellina, n. sp. Lunatia hornii Gabb Venus (?), sp., a Neptunea(?) supraplicata Gabb Venus (?), sp., ~b Neptunea(?), sp. Venericardia planicosta Lamarck, Neverita secta Gabb var. hornii Gabb Olivella mathewsonii Gabb Yoldia(?), n. sp. Perissolax blakei Gabb Zirphaea(?), sp. Pseudoliva volutaeformis Gabb Eimella canalifera Gabb Dentalium cooperi Gabb Surculites, sp. Dentalium stramineum Gabb Turris perkinsiana (Cooper) Amauropsis alveata Gabb Turris, sp., a Bulla hornii Gabb Turris, sp., & Cylichna costata Gabb Turritella merriami Dickerson The basal Tejon in contact with the upper Martinez of the type section is non-fossiliferous and on this account a direct comparison with the upper Martinez is not possible. The Tejon south of Mount Diablo is only ten miles away from the upper Martinez of the type section, so a comparison between the two is profitable. The following species are common to the two : Cardium cooperi Gabb Dentalium cooperi Gabb Leda gabbi (Conrad) Dentalium stramineum Gabb Modiolus ornatus (Gabb) Lunatia hornii (Gabb) Acila, sp. Perissolax tricarnatus(?) Gabb Psammobia hornii (Gabb) Such characteristic species as the following are not found in the basal Tejon : Cucullaea mathewsonii Gabb Fusus aequilateralis Weaver Pholadomya nasuta Gabb Heteroterma gabbi Stanton Tellina kewi, n. sp. Heteroterma trochoidea Gabb Tellina undulifera Gabb Siphonalia(f) lineata Stanton Ampullina striata Gabb Turritella pachecoensis Stanton Brachysphingus liratus Gabb Urosyca caudata Gabb Bullinula subglobosa Weaver This faunal difference would be far better shown, no doubt, if better collecting places in the uppermost Martinez could be found. 116 University of California Publications in Geology [VOL. 8 In making our comparisons between faunas, the condition of deposition should be stated. The fauna of the uppermost Martinez flourished in moderately deep water while that of the basal Tejon is littoral. Luckily we do have a moderately deep-water fauna contained in the Tejon beds just overlying the basal beds. These beds south of Mount Diablo are about fift}^ to seventy-five feet thick and they have yielded Schizaster lecontei, Pecten interradiatus and several species of foraminifers. They are in turn succeeded by Turritella uvasana beds which yield a typical Tejon fauna of the inshore type. These last mentioned horizons are represented at the type section of the Martinez by fossiliferous beds. The Turritella uvasana beds near Muir Station contain a typical Tejon fauna, but the shales and glauconitic sands beneath have yielded a fauna which was so unusual for the Tejon that Dr. "Weaver included it in the Martinez. This fauna is as follows : Loc. Loc. Loc. 215 337 532 Nummuloid(?), sp x Orbitoides, sp x Cardium cooperi Gabb x x Cassidaria tuberculata (Gabb) x Modiolus merriami (Weaver) x Leda gabbi Conrad x Tellina hornii Gabb x Tellina cf. remondii Gabb x Tellina martinezeusis Weaver * x Thracia karquinezensis Weaver x x Solen parallelus Gabb Solen stantoni Weaver x .... x Venericardia planicosta Lamarck x Bela cf. clathrata Gabb x Ficopsis remondii Gabb x Megistostoma striata Gabb Perissolax, n. sp .... x Eimella canalifera Gabb x SpiroglyphusC?) tejonensis Arnold Turris monolifera Cooper x Turritella conica Weaver x Tritonium eocenicum Weaver x Tritonium impressum Weaver x Of these forms Solen parallelus, Venericardia planicosta, Bela clathrata, Ficopsis remondii, Cassidaria tuberculata, Rimella canali- fera, Spiroglyphus(f) tejonensis, Turris monolifera are typical of the Tejon. No typical Martinez species such as Tellina undulifera, Cucullaea mathewsonii, Urosyca caudata or Brachysphingus liratus have been found in these strata. 1914] Dickerson: Fauna of the Martinez Eocene of California 117 TIME-INTERVAL BETWEEN DEPOSITION OF MARTINEZ AND TEJON The time-interval which elapsed between the deposition of these gray-green Tejon shales and the uppermost Martinez strata~rrrast have been very great. During this time many characteristic Martinez species entirely disappeared. A portion of this time-interval is prob- ably represented by unconformity between the lowermost Tejon strata and the Martinez, although there is no one place yet discovered at the type locality which proves this fact. A marked change in lithology, a considerable difference in dip throughout the field, and a very abrupt change in fauna suggest unconformity at the type locality. CORRELATION OF MARTINEZ WITH EOCENE OF THE ATLANTIC AND GULF STATES Dr. W. H. Dall29 first attempted a correlation of the Pacific Coast Eocene with that of the eastern states. In this general correlation paper, the Martinez and Tejon were correlated with the lower portion of the Eocene. Weaver,30 in his paper on the palaeontology of the Martinez Group, correlates the Martinez with the Midway of the Gulf States region. He says : "For comparison with the Martinez fauna, the following important locali- ties have been selected: the Gulf States, the Atlantic States, the London and Paris Basins, and the Sind district of western India. "Compared with these the fauna of the Martinez Group seemed to be a distinct unit. Of the forty-nine genera listed only twenty-two could be found in the literature on the Eocene of the Gulf and Atlantic States. No species were found in common yet several were somewhat similar. This fauna has its closest affinities with that represented in the Midway of the Gulf States and the Aquia stage of Maryland and Virginia. The correspondence to the Aquia is however less marked than to the Midway. . . . The fauna of the Tejon Group bears a closer similarity to both the Aquia and Chickasawan than does the Martinez." Weaver also concludes from a comparison with the London Basin and Paris Basin faunas that the Martinez is more nearly related to the fauna of the Thanet Sands and the Bracheux Beds. He states: ' ' the Martinez may represent some portion or all of the lower quarter of the Eocene." 29 Ball, W. H., 18th Ann. Eept. U. S. Geol. Surv., pt. 2, pp. 327-328, 1898. so Op. cit., pp. 111-113. 118 University of California Publications in Geology [VOL. 8 The writer agrees with Dr. Weaver's position in correlating the Martinez with the Midway of the Gulf States. The Tejon bears a much stronger resemblance to the Aquia and Chickasawan than does the Martinez. Harris31 has given an excellent summary of the Midway stage. GENERA COMMON TO MARTINEZ AND MIDWAY There are several species figured by Harris which are very close to forms found in the Martinez- Ostrea crenulimarginata Gabb resembles Ostrea buwaldana very closely, if it is not identical with it. Modiolus saffordi (Gabb) resembles Modiolus ornatus (Gabb). Cucul- laea saffordi Gabb resembles Cucullaea mathewsonii Gabb. The variety Venericardia planicosta called Venericardia alticostata Conrad resembles a species found in the uppermost Martinez, but none of the species of Venericardia figured by Harris vary from the type of V. planicosta as much as does Cardita veneriformis Gabb. Fulgur(f) dallianum Harris looks like Perissolax blakei. Gyrodes alabamensis Whitf. resembles Gyrodes lineata, n. sp., of the Martinez. Hercoglossa (Enclimatoceras) ulrichi White bears a very close resemblance to Hercoglossa merriami, n. sp. Thus we see that even some specific resemblances can be found between the faunas of the lower Eocene of the east coast and the Martinez of the west. The following genera are common to the Martinez and the Midway : Ostrea Tellina Plicatula Corbula Pecten Lucina Avicula Martesia Perna Pholadomya Modiolus Dentalium Area Actaeon Cucullaea Cyliehna Glycimeris Turris Nucula Pseudoliva Leda Surcula Yoldia Olivella Venericardia Fusus Astarte Triton (=Tritonium) Crassatellites Strepsidura Protocardia Neptunea Meretrix Cypraea si Harris, G. D., The Midway Stage, Bull. no. 4, American Palaeontology, pp. 1-156, June, 1896. 1914] Dickerson: Fauna of the Martinez Eocene of California 119 Cerithium Natica Turritella Gyrodes Architectonica Amaura (= Amauropsis) Calyptraea Fissurella Xenophora Enclimatoceras (= Hercoglossa) Pyrula is the equivalent of Ficopsis. Fulgur(f) dallianum Harris is rather close to Perissolax blakei Conrad. They are generically the same, at least. GENERA PRESENT IN MIDWAY BUT ABSENT IN MARTINEZ The following genera listed by Harris have not been found in the Martinez : Lithodomus Pyropsis Chama Leucozonia Gastrochaena Mazzalina Verticordia Levifusus Cadulus Levibucinum Atys . Murex Pleurotomella Calyptraphorus Drillia Aporrhais Caricella Mesalia Scaphella Eissoina Voluta Keilostoma Lyria Scala Mitra Solariella Exilia Pleurotomaria Of these missing genera the following are found in the Tejon, the upper Eocene of the west coast: Cadulus (represented by Dentalium pusillum Gabb), Drillia, Caricella, Voluta, Mitra, Exilia (represented by Fusus dicker soni Weaver) Lyria, n. sp. PROPOSED CORRELATION The absence of several of the genera mentioned from the Martinez such as Drillia, Caricella, Voluta, Mitra, Exilia, and Pseudoliva which are typical Eocene forms over the world suggests that the Martinez represents a stage in the Eocene of the United States which is at least in part decidedly lower than the Midway. On account of the close relationship of the Martinez to the Chico- Cretaceous, the much greater thickness of the Eocene strata on this coast compared to that of the Gulf States, and the absence of certain genera typical of upper, middle and lower Eocene, the writer con- cludes that the Martinez is not only equivalent to a portion of the Midway, but represents a still earlier stage of the Eocene as well. 120 University of California Publications in Geology [^OL. S SUMMARY Conclusions based upon the work of all investigators are as follows : 1. The Martinez Group is a definite unit both stratigraphically and faunally. 2. An unconformity exists between the Martinez and the under- lying Chico and between the Martinez and the overlying Tejon. 3. The Martinez was deposited in two distinct basins, one being in the vicinity of San Francisco Bay and the other in the neighborhood of Los Angeles. 4. These basins of deposition are only partially coextensive with the larger basin of the Tejon. 5. The faunal differences between Chico and Martinez and between the Martinez and the Tejon are very great. 6. Three major faunal zones have been recognized in the Martinez Group. 7. The Martinez is in part the correlative of the Midway of the Gulf States and in part represents a division of time earlier than the Midway. DESCRIPTIONS OF SPECIES ANTHOZOA FLABELLUM, sp. A short, conical, slightly curved, and somewhat compressed form is found in the Martinez at San Pedro Point. It appears to have about twenty-four principal septa with one or two secondary septa in the interspaces. Costae appear to correspond to each of the principal septa. The principal septa appear bifid but this may be due to weathering. A small, short pedicel is found on some specimens. Dimensions. — Greater transverse diameter of calice, 9 mm. ; lesser, 8 mm. ; height, 8.5 mm. Occurrence. — Martinez at San Pedro Point, San Mateo County, California. PARACYATHUS(f), sp. Plate 6, figure 2 Short, conical, circular, with base truncated, attached at truncation. Costae correspond to all the principal septa which are numerous. About thirty-six of these were counted. One and sometimes two secondary septa are found between the primary ones. Costae appear to be granulated. Wall rather thick. 1914] Dickerson: Fauna of the Martinez Eocene of California 121 Dimensions. — Diameter of calice, 12 mm. ; height, 9 mm. Occurrence. — Martinez of San Pedro Point, San Mateo County, California. ECHINOIDEA CIDAKIS, sp., a Plate 6, figures 4a, 4& Test unknown. Spines long, very slender, circular in cross-section. Certain incomplete specimens are 15 mm. long and only 1 mm. in diameter with only a slight taper. Surface of spine marked by micro- scopic, longitudinal, lines or ribs. The distal end is marked by a small ball which is decorated by about fourteen strong rounded ribs. This ball terminates in a rounded tip. The base is marked by a well- developed collar and a rounded socket in its end. The base does not appear to be ornamented. The surface of the rock is covered with pieces of spines which have been weathered out. The description is based upon several fragments of spines. Occurrence. — University of California Localities 245 and 1556, Martinez Group. CIDARIS(?), sp., c Plate 6, figures 6a, 6b A cast of a hemispherical test with the mouth and apical system, central was found in beds of Martinez north of Mount Diablo. Dimensions. — Height, 4 mm. ; diameter, 6 mm. Occurrence. — University of California Locality 1592, two and one- half miles east of Clayton. SCHIZASTER LECONTEI Merriam Plate 6, figure 7 Schizaster lecontei. — Merriam, J. C., Proceedings, California Academy of Sciences, Geology, vol. 1, pp. 164-165, 1899. California Academy of Sciences, vol. 1. 1 i Small forms averaging a little less than 20 mm. in length. The largest specimen measured is about 23 mm. long. Test distinctly notched anteriorly by the groove of the anterior ambulacrum truncated posteriorly; upper surface much elevated, with a sharp ridge running from the apical system to the posterior end, summit situated far back. Apical system eccentric, posterior, anterior to the summit. "Ambulacra broad, sunken; anterior petals reaching a little more than half way to the margin; posterior laterals very short, less than half the length of the anterior pair, sometimes almost circular in outline. Ambulacral pores elongated, apparently yoked. (?) Mouth opening well forward, broad two-lipped. Anus high up on the truncated posterior end. 122 University of California Publications in Geology [VOL. 8 "Numerous large spines much like those of Schizaster have been found at one locality in the Martinez, but if they belong to this genus at all they were probably derived from another and much larger species. Tubercles larger on the actinal surface. Peripetalous fascicle quite distinct on one specimen. Traces of what appears to be the lateral fascicle have -been seen beneath the anus. "Though crushed fragments of this species have been known to the writer for some years, the first recognizable specimens were discovered by the members of the class in palaeontology in April, 1907. "Not rare in the Martinez in Contra Costa County. Specimens preserved only as impressions or casts, usually badly crushed. ' ' Mr. William Kew has redescribed this species as follows : "Dimensions: Twenty forms averaged 21.3mm. in length, the largest being 35 mm. and the smallest 14 mm. Of nine specimens measured the average height was 14mm., the highest being 22mm. and the lowest llmm. The ratio of height to length varies somewhat. As a rule the length is greater than the height. The average ratio of eight specimens is L:H = 1:0.5999. In one case the ratio is L:H = 1:1.1. ' ' Test deeply and distinctly notched anteriorly by the ambulacra! groove, continuing around to the mouth of the actinal side with slight reduction in the size of the groove. Posteriorly the test is truncated at right angles to the bottom. Upper surface slopes steeply to the front and has a sharp ridge running from the apical center to the posterior end which forms the summit of the test. Apical system, eccentric, anterior to the summit. Shell of test very thin, and rarely preserved. "Ambulacra broad and deeply sunken; anterior petal reaches almost to margin; anterior laterals a little over half way and posterior petals very short and almost circular in outline. Ambulacral pores elongated and consist of two series of three rows each, the middle row of the latter alternating with, and overlapping the outside ones. Extremities of the petals closed. Mouth opening situated about two-thirds the distance forward; broad, two-lipped. Anus high up and at base of the sharp ridge forming the summit. "Apical shield shows madreporic body large and pentagonal in outline. Tubercles small, numerous on both upper and lower surface, regularly spaced. " ' BRYOZOA MEMBRANOPOKA(?), sp. Incrustations doubtfully referred to the genus Menibranopora were found at University of California Locality 765 near Lower Lake, Lake County, California. The zooecia are hexagonal, regularly arranged in quincunx about 0.5 mm. long and 0.3 mm. wide. Surface slightly concave and bordered by an impressed line. BRACHIOPODA RHYNCHONELLA(?), sp. Plate 7, figure 1 A small brachiopod was found at University of California Locality 784 near Lower Lake, which has been referred doubtfully to the genus 1914] Dickerson: Fauna of the Martinez Eocene of California 123 Rhynchonella. Its ventral valve is marked by concentric growth lines and by microscopic radiating lines. A very prominent median fold extends from the center of the shell to its edge. Cardinal slopes gentle, straight. The outer portion of the shell appears to have been removed. Dimensions. — Length, 9 mm. ; height, 8 mm. ; convexity, 3 mm. Occurrence. — Martinez near Lower Lake. PELECYPODA LEDA PACKARDI, n. sp. Plate 7, figures 3a, 35 Shell thin, marked by fine rounded concentric lines, short, convex ; beaks central, small but prominent; anterior dorsal margin, slightly sloping; posterior, straight; anterior end rounded; posterior end bluntly pointed with apex of point at end of straight posterior dorsal margin; base rounded from anterior to middle of posterior ventral margin; from this point the slightly curving posterior margin slopes abruptly upward to the posterior extremity. This species differs from all the other California ledas in shape and in the central position of its beaks. The oddly blunted rostrum is another distinguishing feature. Dimensions. — Length of medium-sized specimen, 10 mm. ; height, 5 mm. ; convexity, 3 mm. Occurrence. — University of California Locality 784; Meretrix dalli zone north of Mount Diablo and the Trochocyathus zitteli zone of the Martinez type section, near Muir Station. Named in honor of Mr. Earl Packard, who assisted the writer in collecting Martinez fossils in Lake County. LEDA MILLERI, n. sp. Plate 7, figure 4 Shell small, moderately convex; beak, prominent, located one-third of the distance from anterior end. Posterior dorsal edge straight with a very slight slope to a blunt pointed posterior end. Anterior dorsal edge straight with a slightly greater slope than posterior dorsal edge. Ventral margin gently convex. This margin curves sharply toward the two pointed extremities of the shell. Dimensions. — Length, 9 mm. ; height, 5 mm. ; convexity, 2 mm. Occurrence. — University of California Locality 1556. Named in honor of Dr. L. H. Miller. 124 University of California Publications in Geology [VOL. 8 This form resembles L. packardi, n. sp., but it has a much less height, its beak is more anterior and its length is greater. It some- what resembles Malletia chehalisensis Arnold in shape. YOLDIA GESTEKI, n. sp. Plate 7, figure 5 Shell thin, very compressed; anterior end, the shorter, and equally rounded above and below; posterior end, slightly longer, pointed; posterior dorsal margin very slightly concave; escutcheon, long, nar- row; base, rounded and most prominent beneath beak, from which point it curves regularly to the pointed, posterior end; beaks, incon- spicuous; sculpture consists of fine, rounded concentric threads. This species is not as convex as Y. cooperi Gabb of the Miocene, its posterior dorsal margin is not as concave as that of Y. cooperi, and the decoration is much finer. Dimensions. — Length, 28 mm. ; height, 12 mm. ; convexity, 2 mm. Occurrence. — Lake County at University of California localities 784 and 790. Named in honor of Mr. Clark Gester, Geologist, Kern Trading and Oil Company. The outline of the shell is restored by a dotted line. YOLDIA(?) POWERSI, n. sp. Plate 7, figure 6 Shell small, thin, elongated, slightly curved, shaped like a pruning knife. Beak, situated a fifth of the length from the anterior end, prominent. Anterior end, broadly rounded; posterior end, pointed sharply. Anterior dorsal margin, convex, short ; posterior dorsal edge, concave, long. An impressed groove extends on the cast from the beak to the posterior end parallel to and just below the posterior dorsal edge. This groove divides the sharply pointed posterior end. Surface marked by rounded concentric lines which do not show on the type. Dimensions. — Length, 10 mm. ; height, 25 mm. ; convexity, 1 mm. Occurrence. — Type specimen at University of California Locality 1556, lower zone, north of Mount Diablo. It is abundant at this locality and appears to be characteristic of this horizon. It is easily distinguished from Y. gesteri, n. sp., by its more prominent beaks, 1914] Dicker son: Fauna of the Martinez Eocene of California 125 by its concave dorsal posterior margin and by its short anterior margin. The knife-like form identifies it readily. Named in honor of Mr. J. R. Powers, who made very careful collec- tions in the Martinez at Selby Smelter. PINNA BARROWSI, n. sp. Plate 8, figure 3 Description.— The shape of the shell is elongate-cuneate. The cross- section of the shell is quadrate-oval. The valves meet on their dorsal margins at a sharp angle which increases from sixty degrees near the base to ninety degrees near the beak. The ventral portions of the valves are rounded. Each valve presents two slopes : a flat, dorsal and a slightly convex, ventral which meet along a radial line. This line divides the shell so that the flat dorsal slope is one-third and the rounded ventral, two-thirds of the total surface. The rounded ventral slope is marked in its central half by approximately eight compressed and slightly elevated radial ribs whose interspaces are twice their width, and by eight to ten concentric rounded ribs in its marginal portion as well as radial ribs, thus further dividing the convex slope into equal parts. These ribs do not show on figured specimen. The flat dorsal slope of the shell is ornamented by about ten compressed radial ribs which are separated by interspaces two times as wide. The nearly straight posterior end makes almost a right angle with the ventral margin. Dimensions. — Total length, unknown. Length of specimen whose beak and lower margin are broken, 30 mm., width, 15 mm., approxi- mate. Occurrence. — Two and one-half miles south of Muir Station and one-half mile east of the road which crosses the Briones Hills going south from Muir Station, on north slope of a small tributary of a tributary of Arroyo del Hambre. Elevation, 550 feet. About 100 yards north of Monterey-Martinez contact, University of California Locality 1547, and at University of California Locality 243. Notes. — Pholadomya nasuta, Trochocyathus zitteli, Urosyca cau- data, Siphonalia(f) lineata, and many other Martinez species are associated with this form. Pinna barrowsi has two kinds of ornamen- tation while P. l)rewerii has but radial ribs. The gore or plait which divides both valves of P. breiverii is approximately central, while the 126 University of California Publications in Geology [VOL. 8 radial line which sets off the flat dorsal portion of P. barrowsi is not central nor is it deeply eroded. This Pinna is also found in the lower Tejon, southwest of Mount Diablo, near Pine Creek, at University of California Locality 1489. Named in honor of Mr. A. L. Barrows. LIMA(?) CLAYTONENSIS, n. sp. Plate 7, figures 9a, 9& Shell inflated, with radial sculpture; rounded and almost sym- metrical. Ratio of length to height about .65 to 1. Beak prominent, acute, and in some specimens compressed. Hinge line short and straight with about twelve small striations perpendicular to hinge line. These striations may be plications within the shell wall, revealed by th breaking away of the inner shell layer. Area, narrowly elliptical and central. Basal margin, rounded. Eibs — about thirteen in number — are acute-angled and beaded; the interspaces are the same in width as the ribs. Dimensions. — Length, 2.5 mm. ; height, 3.8 mm. Occurrence. — Martinez Group, two miles due east of Clayton in beds near base, University of California Locality 1592. It also occurs at localities 1546 and 1557. (See table of localities.) The various features described were recognized from a study of four different specimens. This little shell is quite characteristic of the basal beds or beds about 100 feet above the base at its type localities. It is one of the few species found in the Martinez shales. Named for its occurrence near Clayton. LIMA(?) HASELTINEI, n. sp. Plate 8, figure 2; plate 9, figure 11 Shell large, slightly oblique, nearly equivalve, moderately convex; beak prominent, pointed, anterior, prosogyrate; hinge, edentulous, long, straight; ears not markedly set off from rest of shell, the pos- terior one being the larger ; anterior end broadly rounded ; posterior, slightly truncated; ventral margin, arcuate; decoration consists of numerous squarish radial ribs with very narrow interspaces. Dimensions. — Height of large specimen, 130 mm. ; length, 135 mm. ; convexity, 27 mm. 1914] Dicker son: Fauna of the Martinez Eocene of California 127 Occurrence. — University of California localities 1540 and 1580, both being in the Trocliocyathus zitteli zone of the area north of Mount Diablo. The Stanford University class in field geology, -1910, also found this form in the Martinez just north of the Calabasas Quad- rangle. This is the largest lamellibranch thus far reported from either the Tejon or Martinez on this coast. Named in honor of my friend, Mr. R. S. Haseltine. OSTREA BUWALDANA, n. sp. Plate 9, figure 4 Shell, medium, with thick shell substance, only slightly oblique, elliptical; upper valve flat; lower valve deep, convex and marked by rough, squamose growth lines and about six strong radiating ribs. Muscular scar is reniform, nearly central. Internal margins of some specimens distinctly pitted on both sides of beaks in casts of this species. Occasionally small tooth-like projections are seen on the shell itself on both sides of the beaks. Dimensions. — Length, 35 mm. ; height, 48 mm. ; convexity of lower valve, 5 mm. Occurrence. — University of California localities 790 near Lower Lake and 693 at San Pedro Point, San Mateo County, California. It differs from 0. idriaensis Gabb in that the lower valve is marked by radiating ribs. Its shape is more angular than that of 0. idriaensis. The type is from University of California Locality 790. Named in honor of Mr. J. P. Buwalda. OSTKAEA WEAVERI, n. sp. Plate 9, figure 3 Shell medium in size, subequivalve, irregularly oval, contorted near the beaks, unattached. Surface marked by regular squamose lines of growth. Beak twisted and terminating at the anterior dorsal margin. The upper half is subglobose while the lower half is flat or slightly concave. These two portions are very deeply set off and the species is readily determined by this characteristic. In the lower valve, the bulging of the upper portion is less prominent. The growth lines are remarkably even for this genus. 128 University of California Publications in Geology [VOL. 8 Dimensions. — Length, 23 mm. ; height, 37 mm. ; convexity, 11 mm. Occurrence. — University of California localities 781 and 790 near Lower Lake and 1888 near Selby Station. Named in honor of Professor Charles E. Weaver of the University of Washington. PECTEN (CHALAMYS?), sp. Plate 9, figure 6 Shell minute, subcircular, equilateral, slightly ventricose. Eight valve with exterior surface ornamented by ten squarish ribs, the middle two being decidedly dichotomous; interspaces channeled and about half as wide as ribs; ears nearly equal, markings, obscure. Dimensions. — Length, 3 mm. ; height, 2.5 mm. ; convexity, 1 mm. Occurrence. — Only one specimen was found, at University of Cali- fornia Locality 790. It can be distinguished from all other Eocene pectens on this coast by its small number of external ribs and by the shape of these ribs. MODIOLUS BAKERI, n. sp. Plate 9, figure 8 Shell, medium in size, thick; beak small but prominent, about a sixth of the length from the anterior end which is narrowly rounded ; posterior end, broadly rounded; cardinal margin, straight; ventral margin, slightly rounded; umbonal ridge prominent, rounded, and extending to the posterior end below its center. A marked concavity in larger specimen figured extends from the beaks to the middle of the ventral margin. Surface marked by lines of growth. Dimensions. — Smaller specimen : length, 17 mm. ; height, 8 mm. ; convexity, 4 mm. Occurrence. — University of California localities 243, near Muir Station, and 1556, lower zone of Martinez north of Mount Diablo. This species appears to grow more robust with increase in age. It resembles Modiolus major (Gabb), but its beak is not quite so nearly terminal. The marked concavity on the shell also aids in distinguish- ing it. It differs in shape and in lack of ornamentation from M. ornatus (Gabb). Named in honor of Mr. Charles Lawrence Baker, Geologist, Southern Pacific Company. 1914] Dickerson: Fauna of the Martinez Eocene of California 129 CUSPID AEIA HANNIBALI, n. sp. Plate 9, figure 10 Shell small ; beaks subcentral, of medium size, approximate,-promi- nent and slightly curved anteriorly. Posterior end is about one-third the height of the shell and is produced. The posterior portion of the shell is marked off sharply from the anterior by four transverse rounded ribs which extend from the beak to the base. The interspaces are somewhat wider than the ribs. In two of these interspaces a riblet is found. These ribs do not extend to the posterior tip but end where the posterior portion suddenly narrows, thus dividing the shell into three distinct parts. The anterior portion is rounded and its base is regularly convex. The anterior portion is marked only by concentric lines of growth. A sharp ridge extends from the beak to the dorsal edge of the posterior end and a sharp groove is found between the hinge line and this ridge. Interior unknown. Dimensions. — Length, 10 mm. ( ?) ; height, 5 mm ; width of produced anterior portion near ribs, 2 mm. Occurrence. — University of California Locality 1547, Martinez Group, Trochocyathus zitteli zone. This specimen differs from Neaera dolabraeformis Gabb, which is reported from his "Cretaceous B," in the following ways : (1) Its beak is far less prominent. (2) Its ribs are confined to the central third of the shell, only, while the radial ribs of N. dolabraeformis cover all the shell but the produced posterior end. (3) N. dolabraeformis lacks the prominent ridge extending from the beak to the anterior end. This specimen was found by Mr. Hannibal, who accompanied the writer to the locality. The species is associated with Trochocyathus zitteli, Pholadomya nasuta, Urosyca caudata, Cucullaea mathewsonii, Glycimeris veatchii, var. major and Cardium cooperi. Named in honor of Mr. Harold Hannibal. CRASSATELLITES STUDLEYI, n. sp. Plate 10, figure 1 Shell thick, high, suborbicular ; beaks prominent, prosogyrate, moderately high, approximate, and situated back of mid-length. Pos- terior dorsal margin slightly convex, sloping to the broadly rounded posterior end. A well-marked, narrow escutcheon is set off by two acute ridges from the rest of the shell. Anterior dorsal margin nearly 130 University of California Publications in Geology [VoL- 8 straight, longer than posterior dorsal margin, sloping more steeply than the posterior dorsal margin to a narrowly rounded anterior end. A narrow lunule inset in this margin is slightly concave under the beaks. Ventral margin, rounded. A marked rounded umbonal slope, which extends to a point between the posterior end and the ventral margin, divides the shell into a posterior and an anterior part. The posterior portion is a nearly flat surface while the anterior is convex. Dimensions. — Length, 25 mm. ; height, 22 mm. ; convexity, 7 mm. Occurrence. — Trochocyathus zitteli zone north of Mount Diablo near University of California Locality 1540. This species is distinguished from C. grandis by its greater con- vexity, by its marked umbonal slope and by lack of trigonal shape. It is distinguished from C. stewartvillensis, n. sp., by its more central position of beaks and by its umbonal slope. Named in honor of Mr. C. K. Studley. CRASSATELLITES STEWARTVILLENSIS, n. sp. Plate 10, figure 3 Shell large, thick, trigonal; beaks rounded, prosogyrate, approxi- mate, situated a third of the distance from the anterior end. Anterior end broadly rounded; posterior, rounded but narrower than anterior. Posterior dorsal margin, nearly straight sloping gently to the posterior end ; anterior dorsal margin, short and steep ; ventral margin, nearly straight. A prominent heart-shaped lunule is set off by a rounded ridge. The escutcheon is long and narrow and very definitely limited by two sharp angular ridges which extend along most of its length. Surface marked by growth lines only. Dimensions. — Length of broken specimen, 28 mm. ; height, 25 mm. Occurrence. — Found at University of California Locality 1540, Trochocyathus zitteli zone, north of Mount Diablo. This form differs from C. grandis Gabb in the less central position of the beak, in the slopes of the dorsal margins and in the less convex ventral margin. It differs from C. unioides Stanton in beak position and in its less elongate form. Named for the old coal-mining village of Stewartville, near which it was found. 1914] Dickerson: Fauna of the Martinez Eocene of California 131 CRASSATELLITES CLAYTONENSIS, n. sp. Plate 10, figures 4a, 4b Shell, elongate oval ; beak, prominent and located one-fourth the distance from anterior end; posterior dorsal margin straight, with gentle slope to posterior ; anterior dorsal margin short, concave ; anterior end rounded ; posterior end, truncated. A rounded umbonal slope extends to the junction of the posterior end and the arcuate ventral margin. Surface marked in umbonal region by prominent, rounded, concentric ribs. The specimens are imbedded in the matrix so that a complete hinge cannot be exposed, but the cardinal teeth appear to be those of Crassatellites. Dimensions. — Length, 11 mm. ; height, 8.5 mm. ; convexity, 3 mm. Occurrence. — University of California localities 1558, basal Mar- tinez beds north of Mount Diablo, and 1547, Trochocyathus zitteli zone near Muir Station. Named for the town of Clayton, near which one of the type specimens was found. CAEDITA VENERIFOEMIS Gabb Geological Survey of California, Palaeontology, vol. 1, p. 215, 1864. " Shell small, very convex, subquadrate; beaks rather large, strongly in- curved; cardinal margin nearly straight; posterior end obliquely and convexly truncated; anterior end deeply excavated under the beaks, produced and nar- rowly rounded below; base broadly rounded; hmule broad, deeply impressed. 'Surface marked by about forty fine, acute, radiating, ribs, with sometimes an intercalated one arising in the middle of the shell, and becoming as large as the others before it reaches the base; these are most numerous anteriorly, where all of the ribs are smaller than on the middle; margin strongly crenulated. "Locality: West of Martinez. Martinez Group." This species has the same acute ribs as the young of V. planicosta, and the same variations in form. Some specimens found in the basal Martinez north of Mount Diablo vary from an elongate quadrate form to a high form similar to the high variety of V. planicosta. PHACOIDES QUADKATA, n. sp. Plate 10, figure 6 Shell thin, compressed, markedly quadrate, high; beaks rounded, prosogyrate; posterior dorsal margin straight, sloping moderately to the straight posterior end, which is nearly parallel to altitude line; 132 University of California Publications in Geology [VOL. 8 anterior dorsal margin very slightly convex; anterior end nearly straight; ventral margin rounded; sculpture consists of raised sharp incremental lines with interspaces about three times their width. Dimensions. — Length, 10 mm. ; height, 10 mm. ; convexity, 1.5 mm. Occurrence. — University of California Locality 784 near Lower Lake. The quadrate shape of this species is quite sufficient to distinguish it from other members of the genus. PHACOIDES MUIBENSIS, n. sp. Plate 10, figures lla, 116 Shell small, suborbicular, convex; beaks nearly central; in some specimens slightly posterior to the center. Lunule narrow, small ; escutcheon long, narrow ; posterior dorsal margin nearly straight ; anterior dorsal margin slightly excavated under the beaks; anterior and posterior extremities subtruncate; ventral margin broadly rounded. Surface is marked by strong concentric growth lines and by a very faint, narrow, posterior furrow which is absent in young specimens. This species differs from Phacoides turneri (Stanton) in the trun- cation of the extremities, in the slightly posterior position of the beak and in the lesser prominence of the posterior furrow. Dimensions. — Height, 14.5 mm.; length, 15.5 mm; convexity, 3.5 mm. Occurrence. — University of California Locality 243. Named for its occurrence near Muir Station. PHACOIDES DIABOLI, n. sp. Plate 10, figure 7 Shell thin, equivalve, suborbicular, nearly equilateral ; beaks promi- nent, prosogyrate, central; valves convex; lunule narrow and extend- ing half the length of the straight horizontal anterior dorsal margin ; escutcheon narrow, two-thirds the length of the straight sloping pos- terior dorsal margin and set off in each valve by a high, sharp ridge from rest of shell. A rounded ridge extends from the beaks to the middle of the posterior end; the portion of shell between the umbonal ridge and the ridge bordering the escutcheon is slightly concave; sculpture consists of sharp concentric lamellae with interspaces about three times their width. 1914] Dickerson: Fauna of the Martinez Eocene of California 133 Dimensions. — Length, 23 mm. ; height, 18 mm. ; convexity, 4 mm. Occurrence. — Common at University of California Locality 340, Martinez Group southwest of Mount Diablo. The sculpture resembles that of P. acutilineatus (Conrad) but its height is proportionally much less than that of P. acutilineatus. Its long lunule and escutcheon are also distinctive features. Named for its occurrence near Mount Diablo. DOSINIA(?) LAWSONI, n. sp. Plate 10, figure 9 Shell, medium in size, subglobular, very convex, with full rounded beaks centrally placed ; anterior dorsal margin excavated under beaks, where a small lunule is found ; posterior dorsal margin nearly straight, with steep slope to the rounded posterior end; anterior end narrowly rounded; ventral margin arcuate; surface smooth or marked by fine incremental lines only. Dimensions. — Length, 16 mm. ; height, 14 mm. ; convexity, 4.5 mm. Occurrence. — University of California localities 243 and 340, Mar- tinez limestone southwest of Mount Diablo. The type is a small specimen used on account of its fair preserva- tion. The species is far more convex than the other Eocene species of this genus. In this respect it resembles D. inflata Gabb of the Chico, but the shape and position of the beaks is entirely different. Named in honor of Professor A. C. Lawson, University of Cali- fornia. VENUS (I), sp. Plate 10, figure 10 Shell thick subtriangular, convex ; beaks very high, nearly central ; posterior dorsal margin gently convex, sloping steeply to the rounded posterior; anterior margin very concave and abrupt; ventral margin rounded; lunule indistinct. Dimensions. — Length, 26 mm. ; height, 28 mm. ; convexity, 7 mm. Occurrence. — University of California localities 790, vicinity of Lower Lake, and 340, southwest of Mount Diablo. The specimen is a cast, hence the generic reference is doubtful. It differs from V. lenticularis Gabb of the Chico in that the beak is considerably higher and the posterior dorsal margin is decidedly 134 University of California Publications in Geology [VOL. 8 convex and not straight. The anterior and posterior dorsal margins of V. aequilateralis Gabb are straight, while those of Venus(f), sp., are concave and convex respectively. MERETRIX STANTONI, n. sp. Plate 11, figures la, Ib Meretrix, sp. — Stanton, T. W., The Faunal Relations of the Eocene and Upper Cretaceous on the Pacific Coast, 17th Ann. Rept., U. S. Geolog- ical Survey, p. 1042, 1896. Dr. Stanton in his paper on the Eocene and Upper Cretaceous of the Pacific Coast describes a Meretrix, but does not give it a specific name. Since this form is abundant in the basal beds north of Mount Diablo and the Martinez in Lake County at Lower Lake, and is dis- tinctive, it is thought best to name it specifically. Dr. Stanton 's description is as follows : "One of the most abundant species at the locality one mile southeast of Lower Lake is a venerid apparently belonging to the genus Meretrix and closely resembling the original figure of M. hornii Gabb, but as Gabb discredited that figure when it was published and his later figure and the specimens preserved in the Academy of Natural Sciences, Philadelphia, are not at. all like it, our fossils can not be identified with his species. Possibly this will prove to be a new species, but I shall not venture to name it until several of Gabb 's venerid species represented by conventionalized figures are better known. Shell subtriangular, moderately convex; with thin test; beaks prominent, considerably in advance of the middle, lunule small, deeply impressed; dorsal margin slightly convex behind the beak, sloping rapidly to the narrowly rounded posterior end; anterior end broadly rounded; ventral margin forming a regular curve; surface marked by closely arranged, rather prominent ridges and furrows which vary considerably in size. The numerous specimens collected show considerable variation in relative length of the shells, but this feature does not seem sufficiently constant for specific separation. The dimensions of the largest specimens: Length, 43mm., height, 31mm.; convexity of single valve about 8 mm. The corresponding measurements of a smaller specimen of the short variety are 27, 23, and 6 mm., respectively. ' ' M. stantoni, which is probably related to M. hornii, is more acute posteriorly and the anterior end is higher above. The concentric lines of M. hornii are less numerous and more prominent than those of M. stantoni. This shell apears to be distinct from the short species, M. dalli, described below. It is very abundant in the lower beds of the Martinez formation at University of California Locality 1556, Martinez Group, Mount Diablo Quadrangle, one and one-eighth miles south of Stewartville in the lower beds ten feet above the Martinez- 1914] Dickerson: Fauna of the Martinez Eocene of California 135 Chico contact. Elevation, 1050 feet. E. side of the NW % of Section 15, R. 1 E, T. 1 N, Mount Diablo Baseline and Meridian. MERETRIX DALLI, n. sp. Plate 11, figures 2a, 25 Shell trigonal, convex with very thin test; beaks prominent, in- curved and bent forward, situated slightly in advance of the center; posterior dorsal margin slightly convex and sloping steeply to the rounded posterior end; anterior dorsal margin concave under the beaks, rounded in advance; ventral margin gently convex; lunule small; escutcheon long and very narrow; sculpture consists of fine incremental lines only. Dimensions. — Length, 22 mm. ; height, 17 mm. ; convexity, 6 mm. Occurrence. — This species occurs abundantly in the Martinez near Lower Lake. The type specimen was found at University of California Locality 790. It is also found in the basal Martinez north of Mount Diablo. M . dalli, n. sp., differs from M. stantoni, n. sp., in its much greater convexity, greater height and shorter length, and the concavity of the anterior dorsal margin is much greater. It differs from M. hornii Gabb in shape and sculpture. M. gabbi Arnold is higher and inequi- laterally trigonal, while M. dalli, n. sp., is equilaterally trigonal. M. ovalis Gabb and M. uvasana Gabb have very different shapes than M. dalli, n. sp. MERETEIX, sp. Plate 11, figure 3 Shell very convex, trigonal, beaks anterior being one-third of total length from anterior end; posterior dorsal margin but slightly convex and sloping to a narrow posterior end ; anterior dorsal margin, concave with a well-marked, large, heart-shaped lunule, anterior end broadly rounded ; ventral margin, arcuate ; sculpture, fine lines of growth only. Dimensions. — Length, 12 mm. ; height, 10 mm. ; convexity, 3 mm. Occurrence. — University of California Locality 1556, basal Mar- tinez beds north of Mount Diablo, and University of California Locality 340 southwest of Mount Diablo. This form, though shorter, resembles Meretrix hornii Gabb in shape, but lacks its marked ribbing. It differs from M. stantoni, n. sp., in its larger lunule and greater convexity. 136 University of California Publications in Geology [VOL. 8 MACROCALLISTA(?) PACKI, n. sp. Plate 11, figure 4 Shell elongate-oval in shape; beaks prominent, being situated one- third the distance from anterior end ; posterior dorsal margin straight, sloping gently to a narrowly rounded posterior end; anterior dorsal margin excavated under the beaks, unusually long; anterior end broadly rounded; ventral margin slightly arcuate; shell substance, thin; surface smooth. Dimensions. — Length, 27 mm. ; height, 15 mm. ; convexity, 4 mm. Occurrence. — University of California Locality 790, vicinity of Lower Lake, 1580, Lower Martinez beds north of Mount Diablo, and in the Eocene of San Pedro Point, San Mateo County. This species can readily be distinguished from all other venerid species on this coast by its elongate form and by its long anterior dorsal margin. Named in honor of Mr. Robert Pack, Geologist, U. S. Geological Survey. PAPHIA(?) CLAEKI, n. sp. Plate 11, figure 6 Shell long, narrow, inequilateral; beaks small, placed a third of the distance from the anterior end; posterior dorsal margin slightly convex, sloping to a narrow rounded posterior extremity; anterior dorsal margin concave with a very small lunule upon it ; sculpture, small, regularly rounded ribs. Dimensions. — Length, 9.5 mm. ; height, 6 mm. ; convexity, 2 mm. Occurrence. — University of California localities 790 and 784, vicinity of Lower Lake ; basal Martinez and Trochocyathus zitteli beds north of Mount Diablo. This form resembles Tapes conradiana Gabb closely, but is a shorter form with finer ribbing. The specimens found are all small ones. Named in honor of Mr. B. L. Clark, Instructor in Palaeontology, University of California. TELLINA HERNDONENSIS, n. sp. Plate 11, figure 9 Shell moderate in size, longer than high; beaks nearly central, prominent. Posterior dorsal margin, straight with slightly greater slope than the posterior dorsal margin. Posterior end narrowly 1914] Dickerson: Fauna of the Martinez Eocene of California 137 rounded; anterior broadly rounded; ventral margin nearly straight. A marked, rounded ridge nearly parallels the posterior dorsal margin. Dimensions. — Length, 13.5mm.; height, 10mm.; convexity, 2mm. This species is very similar in form to T. hoffmaniana Gabb which was figured in volume 1, Palaeontology of California (see fig. 1130, pi. 22), but Gabb has undoubtedly confused two different species in this case, as figure 133 is very different. All the specimens from Pence's Ranch in the University of California Cretaceous collections correspond to figure 133, which we will regard as T. hoffmaniana Gabb, a Chico form. Occurrence. — University of California Locality 784. Named for its occurrence near Herndon Creek, Lake County, Cali- fornia. TELLINA PACKABDI, n. sp. Plate 11, figure 11 Shell large, nearly equilateral, compressed; anterior end evenly rounded ; posterior end angulated in middle ; beak central, small ; sides making an angle of 110° at the umbo; anterior dorsal margin slightly convex with abrupt slope nearly equal to that of the straight posterior dorsal margin; ventral margin broadly rounded; surface marked by concentric lines of growth. Dimensions. — Length, 36 mm. ; height, 30 mm. ; convexity, 4 mm. Occurrence. — University of California localities 790 and 784, near Lower Lake. This species differs from T. parilis Gabb, T. aequalis Gabb, and T. lorenzoensis Arnold in its smaller umbonal angle and in its pro- portionally greater height. Named in honor of Mr. Earl Packard. TELLINA PERRINI, n. sp. Plate 11, figure 8 Shell long, very narrow ; beaks small and located two-fifths of the shell-length from the anterior end ; anterior dorsal slope straight, with gentle slope toward the rounded anterior end; the steeper posterior dorsal slope is slightly concave from beaks outward to half its length and then it becomes convex; posterior extremity very angular; basal margin narrowly arcuate; lunule and escutcheon, long and narrow. 138 University of California Publications in Geology [VOL. 8 A straight line which extends from the beaks to the sharp angular posterior extremity marks a prominent umbonal slope. The space between this slope and the posterior dorsal margin is decidedly con- cave. Surface of shell marked by concentric lines of growth. Dimensions. — Length, 33 mm. ; height, 11 mm. ; convexity, 2 mm. This species can be distinguished from all other West Coast Eocene forms of the genus, Tellina, by its great length and marked umbonal slope. Named in honor of Professor James Perrin Smith of Stanford University. TELLINA KEWI, n. sp. Plate 12, figure 1 Shell medium, thin, broad, slightly convex, very inequilateral, but longer than high ; beak small, incurved ; posterior and anterior dorsal margins nearly straight, the posterior sloping the more abruptly; anterior end very broadly rounded; posterior end produced and pointed; ventral margin broadly rounded, more prominent beneath the beaks, and curving from this point abruptly upward to the pointed posterior end. Surface plain, or marked with simple growth lines. This species was probably described and refigured by Gabb32 in the second volume of Palaeontology of California, as Tellina hoffmaniana. He says : ' ' This rather variable species is extremely common in the Martinez group at Martinez, and has been found in the Chico group at Pence's Ranch, as well as in the Tejon group at Griswold's. I have now a single specimen from the latter group from Martinez associated with Turritella uvasana, and other characteristic species. The present figure illustrates a common, and one of the most marked forms of the Martinez group, Martinez, from the same bed with Pugnellus hamulus." The old State Geological Survey specimens now in the collection of the University of California show, upon careful examination, a decided difference between the Chico forms from Pence's Ranch and the ones from Martinez. Several forms which Gabb described from Division A near Martinez have since been proved to be Martinez or Tejon forms. The appearance of the Chico and Martinez sandstones are sometimes very much alike and, if he collected near the Chico-Martinez contact, it is quite likely that he did not distinguish the difference and so placed T. hoffmaniana with the Chico 32 Gabb, Wm., Geological Survey of California, Palaeontology, vol. 2, p. 182. 1914] Dickerson: Fauna of the Martinez Eocene of California 139 form, Pugnellus hamulus. Comparing the true Tellina hoffmaniana, i.e., the Chico form obtained from Pence's Ranch, and described in the first volume issued by the State Survey, with Tellina kewiTursp., the following differences are noted : ( 1 ) The beaks of T. kewi are situated anteriorly, while those of T. hoffmaniana are central. (2) The length of T. hoffmaniana is proportionally greater than T. kewi. (3) The posterior end of T. kewi is pointed, while that of the other is sub- truncated. (4) The anterior end of T. kewi is far more broadly rounded. Dr. Stanton probably compared his specimens obtained from Lake County with Gabb's second figure, and hence identified it as T. hoffmaniana. Dimensions. — Length, 18 mm. ; height, 14 mm. ; convexity, 1 :5 mm. Occurrence. — This Tellina is common at University of California localities 784 and 790, near Lower Lake, Lake County, California. Named in honor of Mr. Wm. Kew, University of California, who has ably assisted the writer in collecting. PSAMMOBIA(f) CYLINDRICA, n. sp. Plate 12, figures 2a, 2& Shell moderately long, thick, convex; beak located a fifth of dis- tance from anterior end, prosogyrate, approximate; nymph narrow, cylindrical, elongate; posterior dorsal margin straight and nearly parallel with the nearly straight ventral margin ; anterior dorsal mar- gin slightly concave under beak, with moderate slope to a narrowly rounded anterior end; posterior end almost straight. A rounded umbonal slope extends from the beak to the angle which the posterior end makes with the ventral margin. Shell ornamented by concentric lines of growth. Dimensions. — Length, 39 mm. ; height, 18 mm. ; convexity, 8 mm. Occurrence. — University of California Locality 780, near Lower Lake village, in the uppermost Martinez. This locality is probably 200 feet below the base of the Tejon. It is also found at the very top of the Martinez, at the type locality. SP1SULA(?) WEAVERI, n. sp. Packard Plate 12, figures 4o, 4& Shell small, relatively thick, subtrigonal to oval, moderately ven- tricose, evenly rounded; umbones nearly central, prosogyrate, promi- nent, nearly adjacent; anterior dorsal margin concave for a distance 140 University of California Publications in Geology [VOL. 8 equal to about one-third the height of the shell; anterior extremity slightly attenuated, evenly rounded; base broadly rounded; posterior evenly rounded, curving gently in the dorsal region to the beak ; sur- face roughened by coarse lines of growth; hinge and interior but imperfectly known. Dimensions. — Length, 32 mm. ; height, 26 mm. ; diameter of one valve, 5mm. Horizon. — Lower Martinez, Meretrix dalli zone. This form varies considerably from the type specimen to an elon- gated form, which is slightly more ventricose. Gradational types are found between these forms. Type from University of California Locality 1556. MARTESIA(?), sp. Shell elongate with thin test; beaks anterior, incurved, approxi- mate ; posterior dorsal margin concave and undulating ; anterior dorsal margin short, rounded; anterior end rounded; posterior end slightly flaring; ventral margin nearly straight. One beaded umbonal groove diverges from the beak. A posterior groove, which indicates the position of an internal rib, makes a very obtuse angle with the ventral margin. Tube unknown. Dimensions. — Height, 13 mm. ; length, unknown. Occurrence. — Found at University of California Locality 784, near Lower Lake. The posterior dorsal margin is concave, while that of Turnus plenus Gabb of the Chico is nearly straight. Its flaring posterior end serves to distinguish it from T. plenus Gabb and Martesia clausa Gabb. Mr. Barrows, who is making a study of boring molluscs, kindly helped me in determining this form. GASTROPODA ACMAEA MARTINEZENS1S, n. sp. Plate 12, figure 8 Shell large, high, elliptical, smooth except for indistinct growth lines; apex rounded and situated two-fifths of length from anterior end ; the slopes on the sides from the apex are much steeper than those to the ends. 1914] Dickerson: Fauna of the Martinez Eocene of California 141 Dimensions. — Major axis, 35 mm. ; minor axis, 23 mm. ; height, 11 mm. Occurrence. — University of California Locality 790. This species differs from A. tejonensis Gabb of the Tejon in having a rounded apex instead of a pointed curved one, and in shape of base. Named for the Martinez group, in which it was found. FISSUEELLA(f) BEHE1, n. sp. Plate 12, figure 9 Shell oval, conical, with form and decoration like an individual coral ; apex acute, with round aperture ( ? ) , located two-fifths of length from anterior end; margin crenulated; surface of shell marked by fourteen acute, nearly straight, radiating ribs with concave interspaces twice their width. Dimensions. — Major axis, 12 mm.; minor axis, 10 mm.; height, 7 mm. Occurrence. — University of California Location 243, Trochocyathus zitteli zone, type locality of Martinez Group. Named in honor of Mr. Ernest Behr. NERITA(?) BIANGULATA, n. sp. Plate 12, figure 12 Shell semiglobose, with low immersed spire, whorls three. The body whorl is marked by spiral lines and transverse nodose ribs. The other whorls are also nodose. Mouth subquadrate. The shell is marked by two angles — a right angle setting off the body whorl from the spire and an obtuse angle which divides the body whorl in halves, both of which are flattened. Inner lip callused with plications; outer lip characters unknown. Dimensions. — Height, 10 mm. ; width of body whorl, 6 mm. Occurrence. — University of California localities 243 and 211. This species is easily distinguished from N. triangulata Gabb by its having only two angulations and by the presence of transverse, nodose ribs. NATICA (GYRODES) LINE AT A, n. sp. Plate 13, figure 3a, 36 Shell of moderate size, solid, thick, moderately elevated, and marked by strong spiral lines. These spiral lines are crossed by growth lines occasionally ; five rounded whorls which are distinctly channeled ; body 142 University of California Publications in Geology [VOL. 8 whorl large ; mouth ovate ; outer lip simple ; inner lip smooth ; umbilicus open and appears to be bounded by a line. Dimensions. — Height, 18 mm. ; width of body whorl, 21 mm. Occurrence. — This species is abundant in the basal beds of the Mar- tinez, University of California Locality 1556, from which the type and co-type were obtained. It ranges from the basal beds to uppermost Martinez. This species is readily distinguished by its prominent spiral lines from all other similar forms in the Eocene, except Bullinula subglobosa Weaver. It differs from Bullinula subglobosa Weaver by having a much wider aperture, by its distinct channeling between whorls, and by a less prominent spire. AMAUKOPSIS MARTINEZENSIS, n. sp. Plate 13, figures 4o, 46 Shell elongated with very high spire for this genus; whorls six; rounded on sides; suture deeply channeled and bordered by a narrow flat margin which slopes to the suture. Aperture half oval; outer lip simple ; inner lip thinly incrusted forming a fold which at first sight seems to be an umbilicus. Surface marked by fine but well-marked revolving lines and lines of growth. Dimensions. — Height, 33 mm. ; width of body whorl, 28 mm. Occurrence. — Martinez Group, University of California Locality 1540, one mile south of Stewartville. This species appears to be the precursor of Amauropsis alveata (Conrad). It has a narrow channeling on upper portion of whorl while A. alveata has a wide slightly concave channeling. The spire of this species is decidedly higher than that of A. alveata. It differs from A. oviformis Gabb in its greater height and in its decoration. TUKITELLA CLAEKI, n. sp. Plate 13, figure 8 Shell short, conical with eleven whorls. When uneroded the whorls lines with flatly channeled interspaces equal in width to ribs. The are nearly flat. A faint angulation can be seen slightly below the center of certain whorls. This angle is marked by a spiral line which is somewhat stronger than the rest. The body whorl appears to have a double angulation, the spiral line below its impressed linear suture marking the upper angle. The decoration consists of flat-topped spiral 1914] Dickerson: Fauna of the Martinez Eocene of California 143 number of spiral lines on the different body whorls is variable. Eight were counted on the penultimate whorl, ten on the next and seven on the eighth. Faint lines of growth cross the spiral lines. Dimensions. — Length, 32 mm. ; width of body whorl, 12 mm. Occurrence. — University of California Locality 1540, Trocho- cyathus zitteli zone north of Mount Diablo. This species resembles T. martinezensis Gabb in its apical angle, but the number of spiral lines is much greater than that of T. mar- tinezensis. Its great apical angle is quite sufficient to distinguish this form from all the other Eocene species of this genus. Named in honor of Mr. Bruce L. Clark, Instructor in Palaeon- tology, University of California. CEEITHIUM, sp. Plate 14, figure 2 Shell robust, conical, with a large apical angle; about twelve flat- sided whorls. These whorls are decorated by about twenty vertical ribs, crossed by about ten revolving ribs. Of the two sets, the vertical is the stronger. The body whorl has the short canal of this genus. Dimensions. — Length of broken specimen, 30 mm. ; width of body whorl about 12 mm. Occurrence. — Abundant, but poorly preserved in the Martinez of San Pedro Point, San Mateo County, California, University of Cali- fornia Locality 692. ALAEIA, sp. Plate 14, figure 3 Shell elongated; spire high; nine or ten whorls; upper whorls spinous, convex, widest a little below the middle; last whorl sharply and acutely angulated, sloping and gently concave above and below the angle ; suture impressed. Surface ornamented by fine, thread-like, revolving lines, and by sinuous lines of growth. Canal long, narrow, straight. Outer lip unicarinate, slightly curved. Dimensions. — Width of body whorl, 11 mm. ; approximate height of spire, 12 mm. Occurrence. — University of California Locality 692. This species resembles Anchura angulata Gabb closely and it may be identical with it, as Gabb's description was based upon a single poorly preserved specimen found at Bull's Head Point. This form may later be found to belong to the genus Spinigera. 144 University of California Publications in Geology [V°L. 8 ANCHURA ENGLISHI, n. sp. Plate 14, figure 5 Shell fusiform with very low spire; six whorls; body whorl large with long, slender, slightly curved canal; lip long, straight. Body whorl shows a node about ninety degrees from expanded lip. The portion of the body whorl above the shoulder slopes gently upward to an impressed suture; decoration, unknown. Dimensions. — Height, 20 mm. ; width of body whorl, 13 mm. ; length of expanded lip, 8 mm. Occurrence. — University of California Locality 243, Trochocyathus zitteli zone at type locality. Named in honor of Mr. Walter English. ANCHUEA GABBI, n. sp. Plate 14, figure 4 Shell small, fusiform, spire elevated, six rounded whorls, suture deep. Surface of upper whorls strongly cancellated by transverse ribs and faintly revolving lines; body whorl strongly marked by two carinae, the upper one of which extends outward to the tip of the lip. Lip long straight perpendicular to whorls, tip acute; canal narrow, length unknown. Dimensions. — Width of body whorl, 6 mm., including lip, 11.5 mm. ; length of whorls, 13 mm. Occurrence. — Martinez Group, one mile south of Stewartville ; University of California Locality 1540. The specimen figured occurs in hard, gray-green, glauconitic sand- stone typical of the Martinez Group. It is associated with Tellina undulifera, Cucullaea mathewsonii, Tapes(f) quadrata, Turritella infragranulata, Perissolax tricarnatus, and Trochocyathus zitteli, characteristic Martinez species. It differs from A. transversa Gabb in having a shorter uncurved lip and its body whorl is marked by two carinae instead of the one as in A. transversa. SERAPHS(?) THOMPSONI, n. sp. Plate 14, figures 6a, 6b Shell elongate, narrow, with spire almost as long as body whorl. Seven whorls rounded, cylindrical. Body whorl is decorated by fine spiral lines crossed by lines of growth. Mouth narrow, long; outer lip simple; inner lip slightly incrusted. 1914] Dicker son: Fauna of the Martinez Eocene of California 145 Dimensions. — Length, 20 mm. ; width of body whorl, 6 mm. Occurrence. — University of California Locality 784, near Lower Lake. Named in honor of Mr. Percy W. Thomson, Geologist, Standard Oil Company. OVULA MARTINI, n. sp. Plate 14, figures la, 7b Shell ovoid, widest about one-third of the distance from the upper end, suddenly narrowing below; under surface flattened. Mouth straight, medium width. Outer lip broad and rounded. Canal un- usually long for this genus. Dimensions. — Greatest width, 28 mm. ; length, 42 mm. Occurrence. — Martinez Group, University of California Locality 243, and two and one-half miles south of Muir Station, and one-half mile east of the road which crosses the Briones Hills going south from Muir Station, on north slope of a small tributary of a tributary of Arroyo del Hambre, elevation 550 feet, 100 yards north of Monterey- Martinez contact. This form differs from Cypraea bayerquei Gabb in that its canal is much longer, it is much thicker and its shape is different. TEITONIUM(?) BUWALDI, n. sp. Plate 15, figure 3 Shell fusiform, robust; spire probably high; number of whorls unknown, the spire being defective. Surface of body whorl orna- mented by about fourteen moderately long nodose longitudinal ribs at thickest part of whorl. These ribs are parallel with the axis. They do not extend to the impressed suture above. Slightly below the middle the body whorl is decorated by eight prominent spiral ribs with interspaces twice as wide. Mouth oval ; inner lip slightly incrusted( ?) ; outer lip, defective ; canal long, slightly curved. Dimensions. — Length of broken specimen, 37 mm. ; width of body whorl, 25 mm. Occurrence. — Only one specimen of this species was found, at University of California Locality 790, near Lower Lake. Named in honor of Mr. J. P. Buwalda. 146 University of California Publications in Geology [VOL. 8 TEITONIUM MAKTINEZENSIS, n. sp. Plate 15, figure 2 Shell fusiform, turreted, spire high and nearly equal in length to mouth; whorls six; suture impressed. Mouth wide above, narrowed in advance, canal slightly curved. Surface marked by prominent nodes on the angles of the whorls, prolonged markedly below, but not above. Well-marked spiral lines of uniform size cover both the nodes and surface of the shell. Dimensions. — Height of shell, 20 mm. ; height of spire, 7 mm. ; width of body whorl, 7 mm. Occurrence. — University of California Locality 1556. This Tritonium resembles T. whitneyi Gabb in some respects. The drawings of T. whitneyi (Palaeontology of California, vol. 1, plate 28, figs. 210 and 210a) are strikingly like this shell, but the type specimen of T. whitneyi differs in the following ways : (1) T. whitneyi has seven or eight whorls; (2) its nodes are only ''prolonged slightly below and above" ; and (3) its revolving lines alternate in size and divide the nodes into two parts. HEMIFUSUS(?) WARINGI, n. sp. Plate 15, figure 10 Shell fusiform, with short spire ; number of whorls unknown ; body whorl biangular, with about fifteen axial ribs which become nodose at the angles. One of the angles is situated at the middle of the outer lip, while the other is slightly below the suture. The suture is enveloped by the preceding whorl. Outer lip simple; columella in- crusted. Canal moderately long and nearly straight. Five rounded, spiral lines ornament the body whorl. • Dimensions. — Height of broken specimen, 28 mm. ; width of body whorl, 22 mm. Occurrence. — The species was found in the upper ( ? ) Martinez along the Santa Fe Railroad, about two miles east of Martinez. It is doubtfully referred to Hemifusus. When better specimens are found it may be placed in the genus Clavella. Named in honor of Mr. C. A. Waring. FUSUS DUMBLEI, n. sp. Plate 16, figure 6 Shell fusiform, whorls nine, angular. Spire about half length of shell. Angulation is central on whorls. Space above and below angles 1914] Dickerson: Fauna of the Martinez Eocene of California 147 is flat or slightly convex. Surface of body whorl marked by ten to twelve spiral lines with interspaces twice as wide; oblique lines of growth are found also. Canal slender, very long, straight^ Dimensions. — Length of spire, 12 mm. ; length of body whorl from suture to constriction, 7 mm. ; width of body whorl, 8 mm. Occurrence. — The type specimen was found by Dr. C. E. Weaver at University of California Locality 790, Lower Lake. Fusus dumblei resembles F. mathewsonii Gabb in its marked angu- lation, but it lacks the double angulation on the lower whorls and it is far less robust than F. mathewsonii. This is the only Fusus thus far reported from the Martinez of Lower Lake. Named in honor of Professor E. T. Dumble, Consulting Geologist, Southern Pacific Company. OLIVELLA CLAYTONENSIS, n. sp. Plate 16, figure 7 Small, spire very low ; whorls four, suture covered ; surface marked faintly by transverse growth lines, mouth not exposed. Outer lip thickened. Dimensions. — Height, 8 mm. ; width of body whorl, 4 mm. Occurrence. — University of California Locality 1543. This species differs from Olivella mathewsonii in height of spire. TUEEIS LOUDERBACKI, n. sp. Plate 16, figures 9a, 9& Shell fusiform, with high spire which is nearly equal in length to the body whorl; eight whorls marked by twelve rounded nodes. The slightly concave space above the shoulder of the whorl slopes steeply from the impressed linear suture. In the whorls of the spire this space is twice as lorg as the nodose convex space below the angle. Fine rounded spiral lines decorate the whorls. Growth lines indicate a sinus at angle. Outer lip simple; inner lip incrusted; canal long, straight. Dimensions. — Length of nearly complete specimen, 35 mm. ; width of body whorl, 13 mm. Occurrence. — University of California Locality 1540, Trocho- cyathus zitteli zone north of Mount Diablo, and same zone at type locality. 148 University of California Publications in Geology [VOL. 8 Its very graceful, long, turreted spire is its distinguishing feature. Named in honor of Professor Gr. D. Louderback, University of California. SURCULA MEBBIAMI, n. sp. Plate 16, figure 10 Shell fusiform, with moderately high spire, with seven or more nodose whorls ; suture line prominent and just below the nodes. About fourteen nodes ornament the body whorl, while only ten are found on the fourth whorl. The nodes are acute, and strong spiral lines mark them. The nodes on the body whorl are much longer than those on the upper whorls. The portion of the whorl between the shoulder and the suture is concave with the center of the concavity two-thirds of the total distance above the nodes. This surface is marked by the curved lines of growth of the sinus, and the apex of the curve is two- thirds the distance above the nodes, thus indicating the position of the sinus. The canal is broken but the upper portion suggests that it is a long one. Dimensions. — Length of broken specimen, 21 mm. ; width of body whorl, 13 mm. Occurrence. — University of California localities 1556 and 1558. The strong spiral lines on the nodes are the distinctive features of this shell. Two specimens have been found. Named in honor of Professor J. C. Merriam. SUBCULA FAIBBANKSI, n. sp. Plate 16, figure 12 Shell spindle-shaped, slender with eight whorls, nodose, convex and angulated in middle ; suture well marked and deep. About ten nodes ornament each whorl. They extend to the suture. The whorls are but slightly swollen. The portion of the whorl between the shoulder and the surface is flat and the lines of growth of this area are curved with the apex of the curve near the suture, indicating that the sinus is above the shoulder of the whorl. The inner lip appears to be slightly incrusted. Dimensions. — Length, 45 mm. ; width of body whorl, 20 mm. Occurrence. — University of California Locality 1540. At first sight this shell looks like Pleurotoma fresnoensis Arnold, but it is much larger, the number of whorls is only eight instead of 1914] Dickerson: Fauna of the Martinez Eocene of California 149 ten of the P. fresnoensis, and its apical angle is decidedly greater. The nodes of this shell are not so pointed as those of 8. crenatospira Cooper. The portion of the whorl between the shoulder and the suture in 8. crenatospira is curved. Named in honor of Dr. H. W. Fairbanks. SUECULA (SUKCULITES) ANDEESONI, n. sp. Plate 16, figure 11 Shell very long, slender ; spire high about two-fifths of length ; nine or ten whorls, nodose, angulated, with sinus slightly above angle judg- ing from growth lines ; twelve or thirteen elongate rounded nodes mark each whorl. The body whorl is distinctly marked by revolving lines which alternate in size. A very distinct collar appears just below the channeled suture of each whorl. Dimensions. — Length of broken specimen, 40 mm. ; width of body whorl, 12 mm. Occurrence. — The type specimen was found at University of Cali- fornia Locality 243, Trochocyathus zitteli zone of type locality. It also occurs at Selby Smelter on the Carquinez Straits. Surcula (Surculites) praeattenuata Gabb of the Tejon resembles this species closely, but its body whorl is decidedly shorter in propor- tion to length. Named in honor of Mr. F. M. Anderson, Curator of Invertebrate Palaeontology, California Academy of Sciences, San Francisco. SUECULA, sp. Plate 16, figures 13o, 136 Shell fusiform, with moderately high spire, with seven or more nodose whorls; suture line prominent and just beneath the nodes. About fourteen nodes ornament the body whorl, while only ten are found on the fourth whorl. The nodes are acute, and strong spiral lines of growth mark them. The nodes on the body whorl are much longer than those on the upper whorls. The portion of the whorl between the shoulder and the suture is concave, with the center of the concavity two-thirds of the total distance above the nodes. This surface is marked by the curved lines of growth of the sinus and the apex of the curve is two-thirds the distance above the nodes, thus 150 University of California Publications in Geology [VOL. 8 indicating the position of the sinus. The canal is broken, but the upper portion suggests that it is a long one. Dimensions. — Width of body whorl, 13 mm. Occurrence. — University of California Locality 1540. CEPHALOPODA HEECOGLOSSA MERRIAMI, n. sp. Plate 17, figures 5a, 56 Shell medium in size, aperture wide; ventral saddles large and simple; lateral lobes well rounded, becoming more acute toward the posterior; lateral saddles well rounded but not so acute as the lateral lobes. Dimensions. — Diameter about 90 mm. Occurrence. — Two specimens have been found at University of California Locality 243, Trochocyathus zitteli zone, type locality of the Martinez. This species differs from H. tuomei Clark and Martin and from H. ulrichi (White) in its more acute lateral lobes and saddles. Its aperture is narrower than that of E. ulrichi. In other respects it resembles this last mentioned species closely. NAUTILUS STEPHENSONI, n. sp. Plate 18, figures 2a, 2& Shell subglobose. Whorls increasing very rapidly in size. The body whorl is large, convex, rounded on sides; the other whorls are immersed in it. Umbilicus covered. Surface decorated by very fine sinuous lines of growth. Septa slightly undulating; ventral lobe slightly concave; the lateral lobe and lateral saddle gently curved. The uniform rounding of the body whorl is a very pronounced feature of this species. Dimensions. — Greatest diameter 32 mm. Occurrence. — University of California Locality 243. This species is decidedly more globose than the species described by Gabb as Nautilus texanus(f) Shumard. Named in honor of the collector, Dr. L. W. Stephenson, Acting Professor of Palaeontology, University of California. 1914] Dickerson: Fauna of the Martinez Eocene of California 151 PEEVIOUSLY DESCEIBED MARTINEZ SPECIES RE-FIGURED Several of the better preserved and characteristic species of the Martinez fauna have been figured in this paper in order that the reader might have comparative forms before him. They are as follows : Flabellum remondianum Gabb. Plate 6, figures la, 15, Ic, Id. Trochocyathus zitteli (Merriam). Plate 6, figures 3a, 35, 3c, 3d. Schizaster lecontei Merriam. Plate 6, figure 7. Terebratulina tejonensis Stanton. Plate 7, figures 2a, 25. Cucullaea mathewsonii Gabb. Plate 7, figures la, 75, 8. Lima multiradiata Gabb. Plate 8, figure 1. Phalodomya nasuta Gabb. Plate 9, figures la, 16. Psammobia hornii (Gabb). Plate 11, figure 10. Mytilus cf. ascia Gabb. Plate 9, figure 2. Pecten interradiatus Gabb. Plate 9, figure 5. Modiolus merriami (Weaver). Plate 9, figure 7. Cuspidaria dolabraeformis (Gabb), Plate 9, figure 9. Plicatula ostreaformis Stanton. Plate 9, figure 12. Crassatellites unioides (Stanton). Plate 10, figure 2. Glycimeris veatchii var. major (Stanton). Plate 10, figure 5. Phacoides turneri (Stanton). Plate 10, figure 8. Tapes (?) quadrata Gabb. Plate 11, figure 5. Tellina undulifera Gabb. Plate 11, figures la, 75, Ic. Tellina cf. parilis Gabb. Plate 11, figure 12. Solen stantoni Weaver. Plate 12, figure 3. Mactra(?) tenuissima Gabb. Plate 12, figure 5. Dentalium cooperi Gabb. Plate 12, figure 7. Discohelix californicus Weaver. Plate 12, figure 10. Architectonica tuberculata Weaver. Plate 13, figures 2a, 25. Lunatia hornii Gabb. Plate 13, figure 5. Lunatia cf. nuciformis Gabb. Plate 13, figures 6a, 65. Xenophora zitteli Weaver. Plate 13, figure 7. Turritella infragranulata Gabb. Plate 13, figures 9a, 95. Turritella martinezensis Gabb. Plate 13, figure 10. Turritella pachecoensis Stanton. Plate 14, figures la, 15, Ic. Cypraea bayerquei Gabb. Plate 15, figure 1. Brachysphingus liratus Gabb. Plate 15, figure 4. Turbinella crassatesta Gabb. Plate 15, figure 5. Urosyca caudata Gabb. Plate 15, figures la, 75. Urosyca robusta Gabb. Plate 15, figure 8. Siphonalia(?) lineata Stanton. Plate 15, figure 9. Neptunea mucronata Gabb. Plate 15, figure 11. Neptunea cretacea Gabb. Plate 15, figure 12. Fusus aequilateralis Weaver. Plate 16, figure 1. Fusus mathewsonii Gabb. Plate 16, figure 2. Fusus occidentalis Gabb. Plate 16, figure 3. Fusus aratus Gabb. Plate 16, figure 4. Fusus flexuosus Gabb. Plate 16, figure 5. Perissolax tricarnatus Weaver. Plate 16, figures 8a, 85. Heteroterma gabbi Stanton. Plate 17, figure 1. 152 University of California Publications in Geology [VOL. 8 Actaeon lawsoni Weaver. Platae 17, figure 2. Bullinula subglobosa Weaver. Plate 17, figure 3. Einginella pinguis Gabb. Plate 17, figures 4o, 4ft. Aturia mathewsonii Gabb. Plate 18, figure 1. All the species figured were obtained from the Martinez Group. Several of Gabb's genera are not in accord with present usage, but they have been retained in this paper in those cases where the correct genus was uncertain. APPENDIX LIST OF LOCALITIES* 65. Concord Quadrangle. Martinez Group. Alhambra Valley. On ridge just east of point where Arroyo del Hambre turns to the north, two and one- quarter miles south of Muir Station. J. C. M. Loc. 65. Concord Sheet. 150. See 340. 243. Concord Quadrangle. Martinez Group. Same as 500 and 544. One and three-fourths miles due south of Muir Station. 267. Concord Quadrangle. Martinez Group. One-sixteenth mile north from Arroyo del Hambre. Two miles south 30 degrees west of Muir Station. J. C. M. Loc. 267. 337. Concord Quadrangle. One and one-quarter miles southeast of Muir Station. On hillside northeast side of Martinez- Walnut Creek road, 75 feet above road. J. C. M. Loc. 337. 340. Mount Diablo Quadrangle. Summer School, 1911. Martinez Group. SE % of NE }4 Sec. 4, K. 1 W, T. 1 S, Mount Diablo Sheet. 333. Concord Quadrangle. Martinez Group. Two and one-quarter miles south, 10 degrees west of Muir Station. J. C. M. Loc. 333. 500. Same as 243 and 544. See Loc. 243. 501 = 213. Concord Quadrangle. Martinez Group. Two and one-eighth miles southeast of Muir Station on the southwest side of Martinez-Walnut Creek road, about one and one-half miles northwest of Grayson's Creek, on side of hill near top, a little to north of Locality 343 but on same hill. J. C. M. Loc. 501 = 213. Concord Sheet. 532. Concord Quadrangle. Eocene. One and three-eighths miles southeast of Muir Station. Across road from 541, on side of hill. J. C. M. Loc. 532. 541. Concord Quadrangle. On south side of road a little over one and three- eighths miles southeast of Muir Station. J. C. M. Loc. 541. Concord Sheet. 544. See 243. * The initials, J. C. M. refer to the collections of J. C. Merriam, and R. E. D. to those of R. E. Dickerson. 1914] Dickerson: Fauna of the Martinez Eocene of California 153 779. Vicinity of Lower Lake, Lake County. Martinez Group, uppermost strata. "SW % of NE % of Sec. 8, T. 12 N, E. 6 W," Map 88. 780. Vicinity of Lower Lake, Lake County. Martinez Group. NW % of SW % of Sec. 36, T. 13 N, E. 7 W; 3000 to 3300 feet (strat.J~ab-ove Mar- tinez base. Limestone in shale. 782. Vicinity of Lower Lake, Lake County. Martinez Group. SE }4 of SE ^4 of Sec. 26, T. 13 N, E. 7 W, in canon whose creek flows past old dam; 2000 to 2500 feet (strat.) above north contact line of Chico- Martinez. Map 88. 784. Vicinity of Lower Lake, Lake County. Martinez Group. NW }4 of NE % of Sec. 11, T. 12 N, E. 7 W, about one-fourth to one-half mile east and a little south of Lower Lake on Knoxville road, 1000 feet (hor- izontal distance) above the Chico-Martinez contact, well at old brick yard. (A Stanton locality.) Map 88. 785. Vicinity of Lower Lake, Lake County. Tejon Group. NW % of SW % of Sec. 6, T. 13 N, E. 6 W, in west gully near hill top. Elevation, 1750 feet. Map 88. 787. Vicinity of Lower Lake, Lake County. Martinez Group. SE *4 of SE % of Sec. 36, T. 13 N, E. 6 W, on south side of Cache Creek. Mar- tinez Group, about 300 feet stratigraphically below Martinez-Tejon contact. Map 88. 788. Vicinity of Lower Lake, Lake County. Martinez Group. SW ^ of SW % of Sec. 1, T. 13 N, E. 7 W, 1000 feet north of Herndon Creek bridge, Knoxville road. Map 88. 790. Vicinity of Lower Lake, Lake County. Martinez Group. SE % of NE % Sec. 11, T. 12 N, E. 7 W, three-fourths of a mile east of Lower Lake, 1200 feet south from bridge over Herndon Creek, in gully on west side of creek. Map 88. 1540. Mount Diablo Quadrangle. (Loc. 91 E. E. D.) One mile south of Stewart - ville, 100 yards south of basal Tejon conglomerate and 600 feet north of Chico-Martinez contact. Elevation, 1000 feet. NE cor. of NW % of Sec. 15, E. 1 E, T. 1 N, Mount Diablo B. L. and M. 1547. Concord Quadrangle. Seven and one-half miles south of north edge of Concord Sheet, just south of Arroyo del Hambre Creek. Martinez sandstone. 1556. Mount Diablo Quadrangle. A little over one mile south of Stewartville, ten feet above the Martinez-Chico contact, in basal Martinez beds. Elevation, 1050 feet. NE ^4 of NW % of Sec. 15, T. 1 N, E. 1 E, Mount Diablo B. L. and M. 1557. Mount Diablo Quadrangle. Sec. 15 E. 1 E, T. 1 N. In Martinez near Chico contact. (Map 61). 1558. Mount Diablo Quadrangle. (Loc. 41 E. E. D.) Martinez Group. Two and one-fourth miles east of Clayton. Elevation, 1450 feet, 200 feet stratigraphically above the Martinez-Chico contact. SW ^4 of Sec. 8, T. 1 N, E. 1 E, Mount Diablo B. L. and M. 1580. Mount Diablo Quadrangle. About one mile south of Stewartville. Ele- vation, 1000 feet, 400 feet stratigraphically above the Martinez-Chico contact. The same stratum as Loc. 1540. NW % of NE % of Sec. 15, T. 1 N, E. 1 E, Mount Diablo B. L. and M. 154 University of California Publications in Geology [VOL. 8 1586. Mount Diablo Quadrangle. Martinez Group. South part of Sec. 8, E. 1 E, T. 1 N, Mount Diablo B. L. and M. 1592. Mount Diablo Quadrangle. Martinez Group. SW cor. Sec. 8, E 1 E, T. 1 N, Mount Diablo B. L. and M. 1695. Mount Diablo Quadrangle. Martinez Group. On hilltop west of point where basal Tejon conglomerate crosses creek. Sec. 14, E. 1 E, T. 1 N, Mount Diablo B. L. and M. 1743. Mount Diablo Quadrangle. Martinez Group. One and one-half miles south of Somerville. Elevation, 950 feet and about twenty feet strati- graphically above the Martinez-Chico contact, in the same zone as 1556. NE cor. of Sec. 16, T. 1 N, E. 1 E, Mount Diablo B. L. and M. 1745. Mount Diablo Quadrangle. Martinez Group. One and one-half miles south of Somerville. Elevation, 900 feet, seventy-five feet strati- graphically above the Martinez-Chico contact. Sec. 16, T. 1 N, E. 1 E, Mount Diablo B. L. and M. 1746. Mount Diablo Quadrangle. (E. E. D. Loc. 506.) Martinez Group. About two and one-fourth miles east of Clayton. Elevation, 1450 feet. About 300 feet stratigraphically above the Martinez-Chico contact. SW cor. of Sec. 8, T. 1 N, E. 1 E, Mount Diablo B. L. and M. 1747. Mount Diablo Quadrangle. (E. E. D. Loc. 507.) Martinez Group. Four miles due east of Clayton. Elevation, 900 feet. About 400 feet strati- graphically above the Martinez-Chico contact in the same strata as 1540. SE cor. of Sec. 9, T. 1 N, E. 1 W, Mount Diablo B. L. and M. 1828. Concord Quadrangle. Martinez Group. On southwest side of Martinez- Walnut Creek road two and one-fourth miles southeast of Muir Station on hill slope. Elevation, 400 feet. Waud and Dickerson. 1829. Concord Quadrangle. Martinez Group. On southwest side of Martinez- Walnut Creek road two and three-eighths miles southeast of Muir Station. Elevation, 475 feet. Waud and Dickerson. 1830. Santa Cruz Quadrangle. San Mateo County between the head waters of San Lorenzo Eiver and Pescadero Creek. See map 47. Dickerson. 1888. Napa Quadrangle. Martinez Group. On road 75 feet above the railroad EXPLANATION OF PLATE 6 Fauna of Martinez Eocene Fig. la. Flabellum remondianum Gabb. X 1. This species ranges from the lowermost to the uppermost Martinez in the Mount Diablo region and the type locality. As far as known it is restricted to the Martinez Group. The proportions of this species are variable. Fig. 1Z>. Fabellum remondianum Gabb, showing a shorter specimen. X 1. Fig. Ic. Flabellum remondianum Gabb. Cross-section view after Vaughan. X 2. Fig. Id. Flabellum remondianum Gabb. Bottom view. X 1. Fig. 2. Paracyathus( '? ) , sp. XI. Fig. 3o. Trochocyathus zitteli (Merriam). X 1. This individual coral is distinctive of the middle zone of the Mar- tinez and restricted to it. Its variations in shape and size are note- worthy. Fig. 3b. Trochocyathus zitteli (Merriam), showing high specimen. X 1. Fig. 3c. Trochocyathus zitteli (Merriam), showing stout specimen. X 1. Fig. 3d. Trochocyathus zitteli (Merriam). Cross-section view after Vaughan. X 3%. Fig. 4o. Cidaris, sp. (a). X 2. Fig. 4b. Cidaris, sp. (a), distal end. X 5. Fig. 5. Cidaris, sp. (d). X 2. Fig. 6a. Cidaris(?), sp. (c), side view. X 2. Fig. 6b. Cidaris(?), sp. (c), top view. X 2. Fig. 7. Schizaster lecontei Merriam. X 1. This echinoderm has an exceedingly great range, being found in the lowermost Martinez and in the uppermost or Siphonalia sutterensis zone of the Tejon Group at the Marysville Buttes. [156] UNIV. CALIF. PUBL. BULL, DEPT. GEOL. [DICKERSON] VOL. 8, PL. 6 la 3a 6a • :.; 6b Id mm. lc EXPLANATION OF PLATE 7 Fauna of Martinez Eocene Fig. 1. Rhynconellaf?), sp. X 3. Fig. 2a. Terebratulina tejonensis Stanton. X 1. This species occurs in the lowermost portion of the Martinez of Lake County and of the Mount Diablo region. Fig. 2fe. Terebratulina tejonensis Stanton. X 1. Fig. 3a. Leda paclcardi, n. sp. X 2. Fig. 3b. Leda paclcardi, n. sp. X 2. Fig. 4. Leda milleri, n. sp. X 2. Fig. 5. Toldia gesteri, n. sp. XI. Fig. 6. Yoldia(?) powersi, n. sp. X 3. Fig. la. Cucullaea matheivsonii Gabb, umbonal view. X 3 . A characteristic Martinez species. Fig. 7b. Cucullaea mathewsonii Gabb, side view. X 1. Fig. 8. Cucullaea mathewsonii Gabb (Area biloba Weaver ). X 3. This figure is Weaver's type of Area biloba which is the young of C. mathewsonii. Small specimens have been recently found which show the hinge of the genus Cucullaea. Fig. 9a. Lima(?) claytonensis, n. sp. X 10. Fig. 9b. Lima( ?) claytonensis, n. sp. X 10. [158] UNIV. CALIF. PUBL. BULL. DEPT. GEOL. [DICKERSON] VOL. 8, PL. 7 7b EXPLANATION OF PLATE 8 Fauna of Martinez Eocene Fig. 1. Lima multiradiata Gabb. X 1. The specimen figured was found at the type locality of this species near Lower Lake. Fig. 2. Lima haseltinei, n. sp. X 1. This form is the largest pelecypod found in the California Eocene. Fig. 3. Pinna barrowsi, n. sp. X 1. This species also occurs in the Tejon. [160] UNIV. CALIF. PUBL. BULL. DEPT. GEOL. {DICKERSON] VOL. 8, PL. 8 EXPLANATION OF PLATE 9 Fauna of Martinez Eocene Fig. la. Pholadomya nasuta Gabb. X 1. This species ranges throughout the Martinez. Fig. 16. Pholadomya nasuta Gabb, umbonal view. X 1. Fig. 2. Mytilus cf. ascia Gabb. X 1. Fig. 3. Ostrea weaveri, n. sp. X 1. Fig. 4. Ostrea buwaldana, n. sp. X 1. Fig. 5. Pecten interradiatus Gabb. X 2 . Eange, Martinez and Tejon. Fig. 6. Pecten, sp. X 2. Fig. 7. Modiolus merriami (Weaver). X 1. This form is also found in the lower portion of the Tejon south of Mount Diablo. Fig. 8. Modiolus bakeri, n. sp. X 1. Fig. 9. Cuspidaria dolabraef ormis (Gabb). X 3. Fig. 10. Cuspidaria hannibali, n. sp. X 2. Fig. 11. Lima(?) haseltinei, n. sp. X 2. Fig. 12. Plicatula ostreaf ormis Stanton. X 1. The form figured is from the type locality of the species, near Lower Lake. UNIV. CALIF. PUBL. BULL, DEPT. GEOL. [DICKERSON] VOL.. 8, PL. 9 10 y? EXPLANATION OF PLATE 10 Fauna of Martinez Eocene Fig. 1. Crassatellites studleyi, n. sp. Fig. 2. Crassatellites unioides (Stanton). This species has a great geographical range, being found in the Martinez of the Santa Ana Mountains and in the vicinity of Lower Lake, Lake County, California. Fig. 3. Crassatellites stewartvillensis, n. sp. Fig. 4a. Crassatellites claytonensis, n. sp. X 2. Fig. 46. Crassatellites claytonensis, n. sp. X 2. Fig. 5. Glycimeris veatchii var. major (Stanton). XI. A common form restricted to the Martinez. Fig. 6. Phacoides quadrata, n. sp. X 2. Fig. 7. Phacoides diaboli, n. sp. X 1. Fig. 8. Phacoides turneri (Stanton). X 1. Fig. 9. Dosinia( ?) lawsoni, n. sp. X 2. Fig. 10. Venus(?), sp. XI. Fig. llo. Phacoides muirensis, n. sp. X 2. Fig. 116. Phacoides muirensis, n. sp., umbonal view. X 2. [164] UNIV. CALIF. PUBL. BULL. DEPT, GEOL. [DICKERSON] VOL. 8, PL. 10 4b 4a 8 9 EXPLANATION OF PLATE 11 Fauna of Martinez Eocene Fig. la. Meretrix stantoni, n. sp. X 1. A species which occurs at nearly all localities of the lower Martinez. Fig. 16. Meretrix stantoni, n. sp. X 1. Fig. 2a. Meretrix dalli, n. sp. XI. A species restricted to the lower Martinez. Fig. 2ft. Meretrix dalli, n. sp. X 1. Fig. 3. Meretrix, sp. X 1. Fig. 4. Macrocallista( ?) packi, n. sp. X 1. Fig. 5. Tapes(?) quadrata Gabb. X 1. Eange, Tejon and Martinez. Fig. 6. Papliia(?) clarU, n. sp. X 2. Fig. la. Tellina undulifera Gabb. X 1. An abundant and easily identifiable form which is somewhat vari- able in shape, as the figures show. Eange, throughout the Martinez. Fig. 7b. Tellina undulifera Gabb. X 1. Fig. 7c. Tellina undulifera Gabb. X 1. Fig. 8. Tellina perrini, n. sp. XI. Fig. 9. Tellina herndonensis, n. sp. X 1. Fig. 10. Psammobia hornii (Gabb). X 1. This Psammobia has a range throughout both the Martinez and Tejon. Fig. 11. Tellina paclcardi, n. sp. X 1. Fig. 12. Tellina cf. parilis Gabb. X 3. [166] UNIV. CALIF. PUBL. BULL, DEPT. GEOL. [DICKERSON] VOL. 8, PL, II lb EXPLANATION OF PLATE 12 Fauna of Martinez Eocene Fig. 1. Tellina kewi, n. sp. X 3. Fig. 2a. Psammobia( ? ) cylindrica, n. sp. X 1. Fig. 2b. Psammobia(?) cylindrica, n. sp. X 1. Fig. 3. Solen stantoni Weaver, after Weaver. X. 1. This species is abundant and rather characteristic of the uppermost Martinez. Fig. 4a. Spisula(?) weaveri, n. sp. Packard. X 1. Fig. 4b. Spisula(?) weaveri, n. sp. Packard. X 1. Fig. 5. Mactra(?) tenuissima Gabb. X 2. Fig. 6. Teredo, sp. XI. Fig. 7. Dentalium cooperi Gabb. X 1. This smooth, large Dentalium is found in the Chico-Cretaceous Martinez, and the Tejon. Fig. 8. Acmaea martinezensis, n. sp. X 1. Fig. 9. Fissurella(f) behri, n. sp. X 2. Fig. 10. Discolielix calif ornicus Weaver, after Weaver. X 1. Fig. 11. Nerita(?), sp. X 2. Fig. 12. Nerita(?) biangulata, n. sp. X 3. [168] UNIV. CALIF. PUBL. BULL. DEPT. GEOL. [DICKERSON] VOL. 8, PL 12 12 10 2a 4a •4b EXPLANATION OF PLATE 13 Fauna of Martinez Eocene Fig. 1. Architectonica, sp. X 1. Fig. 2a. Architectonica tuberculata Weaver, after Weaver. X 1. Fig. 2b. Architectonica tuberculata Weaver. Detail. X 6. Fig. 3a. Natica (Gyrodes) lineata, n. sp. XI. Fig. 35. Natica (Gyrodes), sp. X 1. A common but poorly preserved form in the Martinez. Fig. 4a. Amauropsis martinezensis, n. sp. XI. A form which is common in the middle zone of the Martinez. It appears to be intermediate between A. oviformis of the Chico and A. alveata of the Tejon. Fig. 4b. Amauropsis martinezensis, n. sp. X 1. Fig. 5. Lunatia hornii Gabb. X 1. Kange of this species is Tejon and Martinez. Fig. 6a. Lunatia cf. nuciformis Gabb. X 3. Fig. 6b. Lunatia cf. nuciformis Gabb. X 3. Fig. 7. Xenophora zitteli Weaver, after Weaver. X 1. A form which is restricted to the middle or Trochocyathus zitteli and the lowermost or Meretrix dalli zones of the Martinez. Fig. 8. Turritella clarlci, n. sp. X 2. Fig. 9a. Turritella infragranulata Gabb. X 2. The figured specimen is from the Martinez of the Santa Ana Mountains. Fig. 9&. Turritella infragranulata. X 2. Fig. 10. Turritella martinezensis Gabb. X 1. This form was found in Martinez strata near Eock Creek, Los Angeles County, California. [170] UNIV. CALIF. PUBL. BULL. DEPT. GEOL. [DICKERSON] VOL. 8, PL. 13 3a EXPLANATION OF PLATE 14 Fauna of Martinez Eocene Fig. la. Turritella pachecoensis Stanton. X 1. This very characteristic Turritella has been erroneously reported from the Tejon. It appears to be wholly restricted .to the Martinez. Eange, lowermost to uppermost Martinez. Fig. Ifc. Turritella pachecoensis Stanton. X 1. Fig. Ic. Turritella pachecoensis Stanton. X 1. Nodose specimen from the Santa Ana Mountains. Fig. 2. Cerithium, sp. X 2. Fig. 3. Alaria, sp. X 1. Fig. 4. Anchura gabbi, n. sp. X 2. Fig. 5. Anchura englishi, n. sp. X 3. Fig. 6a. Seraphs(.?) thompsoni, n. sp. X 3. Fig. 6b. Seraphs(.?) thompsoni, n. sp. X 3. Fig. la. Ovula martini, n. sp. X 2. Fig. 7b. Ovula martini, n. sp. X 2. [172] UNIV. CALIF. PUBL BULL. DEPT. GEOL. [DICKERSON] VOL. 8, PL. 14 7b EXPLANATION OF PLATE 15 Fauna of Martinez Eocene Fig. 1. Cypraea bayerquei Gabb. X 1. Range, Tejon and Martinez. Fig. 2. Tritonium martinezensls, n. sp. X 2. Fig. 3. Tritonium buwaldi, n. sp. X 1. Fig. 4. Brachysphingus liratus Gabb. X 1. A very easily identifiable and characteristic Martinez species. Fig. 5. Turbinella crassatesta Gabb. X 2. Fig. 6. Ficopsis, sp. XI. Fig. la. Urosyca caudata Gabb. X 1. This species changes with increase in size. The nodes become larger and less numerous in large specimens. Fig. 71). Urosyca caudata Gabb. X 1?. Fig. 8. Urosyca robusta Weaver. X 1. From a locality near Selby Smelter. Fig. 9. Siphonaliaf?) lineata Stanton. X 1. Fig. 10. Hemifusus waringi, n. sp. X 2. Fig. 11. Neptunea mucronata Gabb. X 1. A characteristic Martinez species. Fig. 12. Neptunea cretacea Gabb. X 1. [174] UNIV. CALIF. PUBL BULL DEPT. GEOL. [DICKERSON] VOL. 8, PL. 15 10 EXPLANATION OF PLATE 16 Fauna of Martinez Eocene Fig. 1. Fusus aequilateralis Weaver. X 2. Fig. 2. Fusus mathewsonii Gabb. X 1. Eange Tejon and Martinez. Fig. 3. Fusus occidentalis Gabb. X 1. Fig. 4. Fusus aratus Gabb. X 1. Fig. 5. Fusus flexuosus Gabb. X 2. Fig. 6. Fusus dumblei, n. sp. X 2. Fig. 7. Olivella claytonensis, n. sp. X 3. Fig. 8a. Perissolax tricarnatus Weaver. X 1. This species may be only a variety of P. blakei Conrad, as it is found in the type Tejon along with the bicarnate form. The tricarnate form is however the commoner in the Martinez. Fig. 8b. Perissolax tricarnatus Weaver. X 11 Fig. 9a. Turris louderbacTci, n. sp. X 1. Fig. 96. Turris louderbaclci, n. sp. XI. Fig. 10. Surcula merriami, n. sp. X 1. Fig. 11. Surcula (Surculites) andersoni, n. sp. X 1. Fig. 12. Surcula fairbanksi, n. sp. X 1. Fig. 13a. Surcula, sp. X 1. Fig. 136. Surcula, sp. X 1. [176] UNIV. CALIF. PUBL. BULL. DEPT. GEOL. [DICKERSON] VOL. 8, PL. 16 8b 8a 13. W 13b w 12 EXPLANATION OF PLATE 17 Fauna of Martinez Eocene Fig. 1. Heteroterma gabbi Stanton. X 1. Fig. 2. Actaeon lawsoni Weaver. X 3. Fig. 3. Bullinula subglobosa Weaver, after Weaver. X 2. Fig. 4a. Einginella pinguis Gabb. X 2. A species found in the middle and lower portions of the Martinez. Fig. 4b. Einginella pinguis Gabb. X 2. Fig. 5a. Hercoglossa merriami, n. sp. XI. Fig. 5b. Hercoglossa merriami, n. sp. X 1. This species may be related to the eastern species Hercoglossa (Enclimatoceras) ulrichi White. [178] UNIV. CALIF. PUBL. BULL, DEPT. GEOL, [DICKERSON] VOL. 8, PL. 17 5a 4a 5b EXPLANATION OF PLATE 18 Fauna of Martinez Eocene Fig. 1. Aturia mathewsonii Gabb. X 1. This cephalopod occurs both in Martinez and Tejon. Fig. 2a. Nautilus stephensoni, n. sp., side view. X 1. Fig. 2b. Nautilus stephensoni, n. sp., back view. X 1. [180] UNIV. CALIF. PUBL. BULL. DEPT. GEOL. [DICKERSON] VOL. 8, PL. 18 VOLUME 5 — (Continued}. PRICK 6 Notes on Lawsonite, Columbite, Beryl, Barite, and Calcite by 7 The Fossil Fishes of California, with Supplementary Notes on Other S. ^^J^^ 5c 9 Berito^VS^^^^ ™th 5c Chemical Analysis by Walter C. Blasdale ..... ..... ------"-"• ........ •••- 15 * 16 Str^gra^nV a^^ala^io^-S-Se^nPaSo- Fiction in Middle California, ^ 20 Ths 15. 23. ey ,OC by 28 Thbery neen- Asia'and North America, by ^ 29 Eoian?kun7^-the-IaTe--TertiarFBeds- at' Virgin "Yailey and Thousand Creek, ^ SO. WaNd1nf B',rbdl ^t^t^^"^^"^Tof]^^ ^ Holmes Miller ..................................................... VOLUME 6. Nevada, by John C. Merriam Part I--^.^.0PC 1?0^ "" 25c „, •- 7. A CoUecTon of Mammalian Eemains from Tertiary Beds on the Mohave Desert, by John, C. Merriam. 10c 8 The 8?r°ati£$J ^^ ^^^''ot'^'^^'^^^'^^ Chic° 5c . 1?: A 13 Note"™ tne"EeWionships-of-tne''Marine-Saurian'Fanna DeBCribed_from the Triassic c. Nna. 13 and 14 in one cover VOLUME 6— (Continued). PRICE ].". Notes on the Later Cenozoic History of the Mohave Desert Eegion in Southeastern California, by Charles Laurence^Baker .~>0c Hi. Avifauna of the Pleistocene Cave Deposits of California, by Loye Holmes Miller .... 15c il Beaver from the Kettlernan Hills, California, by Louise Kellogg ."5c us Desmostylus of Marsh, by John C. Merriam 10c 19. The Elastic-Rebound Theory of Earthquakes, by Harry Fielding Reid L!.~>C VOLUME 7. 1. The Minerals of Tonopah, Nevada, by Arthur S. Eakle 25e •2. Peeudostratification in Santa Barbara County, California, by George Davis Louder- back 20c ;!. Recent Discoveries of Carnivora in the Pleistocene of Rancho La Brea, by John C. Merriam oc 4. The Neocene Section at Kirker Pass on the North Side of Mount Diablo, by Bruee L. Clark .". ].lc 5. Contributions to Avian Palaeontology from the Pacific Coast of North America, by Loye Holmes Miller 60c 6. Physiography and Structure of the Western El Paso Range and the Southern Sierra Nevada, by Charles Laurence Baker v 30c 7. Fauna from the Type Locality of the Monterey Series in California, by Bruce Martin. lOc 8. Pleistocene Rodents of California, by Louise Kellogg 15e 9. Tapir Remains from Late Cenozoic Beds of the Pacific Coast Region, by John C. Merriam 10c 10. The Monterey Series in California, by George Davis Louderback 65c 11. Supplementary Notes on Fossil Sharks, by David Starr Jordan and Carl Hugh Beal ... lOc 12. Fauna of the Eocene at Marysville Buttes, California, by Roy E. Dickerson 45c 13. Notes on Scutella norrisi and Scutaster andersoni, by Robert v\f. Pack 05c 14. The Skull and Dentition of a Camel from the Pleistocene of Rancho La Brea, by John C. Merriam 20c 15. The Petrographic Designation of Alluvial Fan Formations, by Andrew C. Lawson.... lOc 16. A Peculiar Horn or Antler from the Mohave Miocene of California, by John C. Mer- riam r,c 17. Nothrotherium and Me-alonyx from the Pleistocene of Southern California, by rer Stock ,_* *.. 15c • n the Ganid (ieiius Tephrocyon, by John C. Merriam Me lU. Vertebrate Fauna of the Orindan and Siestan Beds in Middle California, by John ( '. M rrriam .; lOc -". Beeenl < >i>s«>rvations on the Mode of Accumulation of the Pleistocene Bone Deposits of Rancho La Brea, by Reginald C. Stoner lOc 21. Preliminary Report on the Horses of Rancho La Brea, by John C. Merriam I'lir 22. New Anchitheriine Horses from the Tertiary of the Great Basin Area, by John C. Merriam 15C 23. New Protohippnic Eorses from Tertiary Beds on the Western Border of the Mohave Desert, by .John C. Merriam :>(- 24. Pleistocene Beds at Manix in the Eastern Mohave Desert Region, by John 1*. Hu wah la ;_'.-„. 25. The Problem of Aquatic Adaptation in the Carnivora, as Illustrated in the Oste- ology and Evolution of the Sea-Otter, by Walter P. Taylor 30c VOLUME 8. 1. Is the Boulder "Batholith" a Laccolith? A Problem in Ore-Genesis, by Andrew C. Lawson .: I_TM 2. Note on the Faunal Zones of the Tejon Group, by Roy E. Dickerson K)c 3. Teelh of a Cestraciont Shark from the Upper Triassic of Northern California, by I laiohl ( '. Bryant : .",,- 4. Bird KVrnains from flic I'h-isl oc<-m> of San I'rdro, ( 'a li forma, hv Love llnlmrs Miller. l