AX ~ \ ANG ~~ \ AN \ \ NAS A . WH \\ \\ A \\ | FEB 28 4907 ol = » i} : Geological Survey of the State of Hew Work. Pew ON EO COR ie Votume VIII. AN JON IMR OID UCT ION WO) AMsOs; {Se Gi ID) iv OF THE GENERA OF PALAOZOIW IEIRIVOIEHEOIEO IDA. IP AIRW JC, BY JAMES HALL, STATE GEOLOGIST AND PALRONTOLOGIST. ASSISTED BY JOHN M. CLARKE. ALBANY, N. Y.: CHARLES VAN BENTHUYSEN & SONS. 1892. VRE RERS VEOIOOS CGd Eun CEM ZOOIREN YD Published under the supervision of the Trustees of the State Museum of Natural History, pu chapter 355 of the Laws of 1883. State or New York, a Avpany, June, J JD) Jeb ID) EO eX PEO) INT To His Excellency ROSWELL P. FLOWER, Governor of the State of New York: Sir: I have the honor to present to your Excellency a new volume of the Naturat History or THE State or New York, forming a continuation of the work on the Paleontology of the State. This volume together with one other, already far advanced in its prepara- tion, will complete the work upon the revision of the genera of the Patmozoic Bracniopopa. The investigation, begun many years ago, and for a long time suspended, was resumed only in 1888, and while in the outset laboring under many disadvantages for want of adequate collections, the difficulties have been mainly overcome and the author is able to present the volume in a satis- factory form. The advance in our knowledge of this class of fossils during the past twenty-five years, and the later accumulation of material from various sources, for the illustration of the work, are the causes which have expanded the proposed Part ii of Volume IV of 1867 into two volumes, of which this is the first. The work has for its final object the bringing together, under one title, a summary and revision of all the genera of this class of fossils known in the rocks of New York and the adjacent States, to the Coal Measures inclusive. This will also serve as a revision of the genera and species already described in Volumes I to IV of the Palzontology of New York, published during the interval from 1847 to 1867. The publication of the volume has been greatly delayed by causes beyond the control of the author, but the Act of the Legislature, Chapter 170 of the lv DEDICATION. Laws of 1892, has made provision for the completion of this and the subse- quent volume. The present volume is the first fruit of that act, and I trust that its publication may give you personal satisfaction, and that it may com- mend itself to the student of geological science and prove worthy of a place among the great series of works comprising the Natural History of the State of New York. ; I have the honor to remain, ~ With great respect, Your obedient Servant, JAMES HALL, State Geologist. Aupany, N. Y., May 18th, 1892. iPS hit Ok CONDENS: DEDICATION eee eS fe OS) i, TWAT OF COMMAS = 5 Se Ua ee SO th PREFACE - - - = < - = : 2 2 z 3 “ Bsc sant I. BRACHIOPODA INARTICULATA - - = = - = = o 1 LincuLa - - - - = - = = = = S = 5 ) Linauiors - - - - - E : 2 : 2 : 3 18 LINGULASMA - - - - - = - - : = = : = Ml LAKHMINA - - - - : = - = = = é = 98 TRIMERELLA - - - - = = = = = = = - DrNopoLus - - : = : - = z s 2 L 2 36 MonoMoRELLA - - = = : 2 oats Mees Ses, a) RHINOBOLUS - = - = - oi ole mae E > wa 44 Observations on the Development of the Platform, ete. - - eer = 46 LINGULELLA. - - = = a S S = 5 = 5 = 55 LInGULEPIS - - = = = Es = = & < F t - BARROISELLA - - = = 2 2 . = = s 3 - 62 ToMASINA — - - - = = = = - = 2 2 Z = 6% OBOLELLA - - 2 = 2 : - e m 2 3 66 LEPToBoLus - - - = = = - = = 5 = > 7B ELKANIA 2 é a = Es = e = 2 ng i & 75 PATERULA - - - = = = : - = = s = 78 OBOLUS - - - 2 = 2 = = = = z = - 80 AULONOPRETA - - - = - = - = - = = - 82 ScHMIDTIA - = : = = S 2 = = 2 a 2 88 Monoso.ina - = - - 3 = = 2 3 = = - 83 NEOBOLUS - - - = = = = = 7 Z 3 ‘5 84 SPONDYLOBOLUS = - = = = = = é = : L S - Mickwitzia - = - A ee = = z & mS e a 86 ScHIZOBOLUS = = z 2 E z £ = y i bs . DISCINOLEPIS = - - - = = = : - = = = = 90 KUTORGINA - - - - - - = - = = = = 5 SCHIZOPHOLIS = - - = - = 2 = = - = 2 a 94 VoLBORTHIA - - - = - - = = - = = = OF IpHIDEA - - - - - = = - - - = Shin 97 ACROTHELE - - - = = = = - = = 2 2 SIO Q) ACROTRETA - - - - - - < so th ker) ute 101 vl CONOTRETA - DisciNopsis - SINNARSSONIA Mersorreta - > SIPHONOTRETA ScHIZAMBON = K&yYSERLINGIA HELMERSENIA Discina, ORBICULA, ORBICULOIDEA, QSHLERTELLA, ROPMERELLA TREMATIS - SCHIZOCRANIA CRANIA - - CRANIELLA - CARDINOCRANIA PHOLIDOPS” - Note to page 128 - - CONCLUSION - - SUPPLEMENT TO THE II. BRACHIOPODA ARTICULATA ORTHIS — - = Orthis S Plectorthis — - Dinorthis - Plesiomys = - Hebertella Orthostrophia Platystrophia Heterorthis - Bilobites - Dalmanella - Rhipidomella Schizophoria - Orthotichia Enteletes - List oF GENERA AND BILLINGSELLA PROTORTHIS - CLITAMBONITES PoLyrascHIA —- ScENIDIUM - ORTHIDIUM : BRACHIOPODA INARTICULATA - SPECIES SupPLEMENTARY Nove on THE GENUS OF SCHIZOTRE' OrTHIS CONTENTS. TA, Di LINDSTROEMELLA, 9 YU OS Ww bo bo bw bo bo bo Pg ne fies m= OW CN TABLE OF CONTENTS. vil PAGE. STROPHOMENA - - - = = = = = = Z 3 2 945 ORTHOTHETES - - - - = = = = = 2 = = OER HIPPARIONYX - = » = 2 2 o a : A a : 257 KAYSERELLA - - - - = = = = : z = - 959 DERBYA - - - - - - = = = iS = pa ‘ie 261 MEEKELLA - - - - - = : = S = = = - 9964 S@REPTORHYNCHUS = - - - - = - 2 = 2 = a 267 TRIPLECIA —- - - - = = - 4 = 2 s 2 - 269 Mimuius - - - - - - - - : = = 7 972 STREPTIS - - - = - 2 - = SN 5 ee 7A LEPTEANA - - - - - = : = : : = = a 276 RAFINESQUINA - - - - - - - = 3 E = - 981 STROPHEODONTA - - - - - : : : 2 : : 984 STROPHONELLA - - = = = - = = 2 a - 990 LEPTELLA - - - = - - 2 - Z 2 z : 993 LEPTHNULOPSIS— - - - = = - = = = : = - 294 PLECTAMBONITES - = : = : = z ie 5 2 . 295 CHRISTIANIA - - - - = = - = 7 = = 2 - 9298 LEPTANISCA - - - = = = : 5 2 H z = 999 DAVIDSONIA - - - - - = : = - = e 3 = Rl CHONETES - - - : 2 - = 2 = 2 e 2 303 CHONETINA - - - - - - - = - = 5 = = S10 CHONOSTROPHIA - - - = = = = = 2 2 Ss 5S She “ CHONETELLA— - - - - - = - 2 = : A 313 STROPHALOSIA - - - - - = = = > 5s = - 314 DAVIESIELLA -~ - - - - = = - : = = = 317 AULOSTEGES - - - - - - < - 2 = 2 P - 319 Ppropuctus - - - - - - = = - = é 2 391 PRODUCTELLA - - - = = - ‘ = = z 2 - 398 PROBOSCIDELLA - - - - - = = - 2 2 333 ETHERIDGINA - - - = - = = 2 = = 2 - 335 SuppteMenTARY Nore on THE GENUS OBOLUS - - - - = = 337 Descriptions oF NEW SPECIES - - - - - - - = = - 340 THN IDIDD Cee ee eee Re ie ee eS, a 4 BEE Je Jes J © Aah, Tue completion of the present volume is a partial fulfillment of a promise made at the close of Volume LV of the Palzeontology of New York, in 1867. The work is presented to the student with a hope that it may prove a useful con- tribution to science and a helpful guide in the study of that most abundant and most important class of Paleeozoic fossils, the Brachiopoda. Originally intended to form a supplementary part of Volume IV, the subject has expanded to such an extent that two volumes will be required to present the results with a reasonable degree of completeness; and even with this addition some very important matter, as the microscopic shell structure, originally intended for the work, will have to be omitted from these volumes. The study of the Brachiopoda made necessary in the preparation of Volumes III and IV, and more especially in the latter, had shown the necessity of sub- dividing many of the older recognized genera, which had become the receptacle for forms having external similarity to the typical members of the several groups, but possessing quite dissimilar internal features. The natural disinclination to propose new generic terms for members of a class of fossils which had been so widely and thoroughly studied in Europe, operated as a restriction in the erection of new names. However it became necessary to describe in those volumes and in cotemporary papers some thirty-one new generic forms and to suggest the necessity for farther separation among other heterogeneous assemblages. These studies, made with fairly good collections, and ranging through the Silurian and Devonian faunas, could not fail to attract attention to the different external aspects and interior characters of forms known under the same generic terms, and considered as distri- buted through all the Palzozoic formations. Although the genera thus far proposed had not been based upon a recognition of their appearance and duration in geological time, yet the student could not fail to discover evidences xx PREFACE. of organic change in this direction. While discussing certain generic and specific forms as characterizing known geological horizons or certain groups of strata, we had not yet taken into consideration the fact that modifications of organic types had been coincident with every change or progress in geological time. The great law of progress through long intervals had been everywhere recognized in geological science, but just how or in what manner these changes had supervened had rarely been shown in detail. Certain fossil genera have long since been recognized as Silurian, others as Devonian, and others as Carboniferous, but these are never entirely restricted to the formations which they are said to characterize. They have all doubtless been derived from some remote progenitor, and at certain horizons, or throughout certain forma- tions have become so abundant and so fully developed, that they are said to characterize that stage or formation. The most abundant and extravagant forms among fossil organisms can usually be traced to some parent stock of more modest pretensions, and in their early appearance, represented by few individuals. As stated, the studies of the Brachiopoda to the close of Volume IV of the Paleontology had shown the importance of some investigation which should deal directly with these questions. And moreover the science demanded the results of such an investigation in aid of its future progress. The original conception and plan of the work which the author had proposed to himself was a very simple one, viz. to select the earliest representative of a genus in any of the geological formations and to follow it through all its manifestations and modifications in geological time, to its final disappearance ; or so far as these modifications should appear in the Palzeozoic rocks, to which he had limited his research.* With the knowledge then possessed and with the collections at his disposal he had supposed that the result of such an investigation could be embraced in a supplementary part to Volume IV, and under this title the work was announced. This study was commenced very soon after the publication of that volume and its general plan *The difficulty of procuring sufficiently abundant and characteristic collections of the later forma- tions was in itself a sufficient barrier, and the scope of the work did not contemplate the discussion of Mesozoic and later genera, except in an incidental manner. PREFACE. X1 was carried out so far as the lithographing of about thirty plates, when the farther progress of the work was suspended, to be resumed only in the latter part of 1888. In the meantime the duties of the author had separated him almost entirely from this work, and owing to changes, over which he had no control, in the organization and management of the State Museum, the collections which he had planned to make for use in its preparation had not been made. The progress in our current knowledge of the subject, and that recorded in the publication of volumes and miscellaneous papers during more than twenty years had been enormous, and the undertaking which had been deemed feasible in 1867, seemed almost beyond attainment in 1888. The work was resumed however, with no other collections immediately available for use, than those upon which it had been commenced. In the original plan four plates were left for the illustration of the Inarticulata; the present volume furnishes ten additional plates, and the illustrations of these forms may be regarded as fairly complete, according to our present knowledge. The plates which were lithographed at the commencement of the work are designated on the upper left-hand margin as “ Volume IV, Part II.” Those lithographed since 1888 are designated as Volume VIII, and while the illustra- tions.of the first named plates are not always arranged as would have been done with later knowledge and more abundant material, it is hoped that the intercalation of the new plates may not seriously interfere with the proper connection and continuity of the work, or with the facility of reference so important to the student. Although the final numbering is XX, the actual number of plates in the volume is forty-two. The printing of this volume had been completed to the end of the Inarticulata, page 183, in March, 1890, when farther progress was suspended, from causes over which the author had no control. The printing was resumed in the autumn of 1890, and the book was in type to page 304 in February, 1891, when its progress was again suspended to be resumed only in April, 1892. This delay in publication, which has not in any way been due to the author, requires an apology to the scientific public; and those authors who may have xii _ PREFACE. published papers relating to the Brachiopoda, during 1890 or 1891 which could not be cited in this volume, will here find the explanation. At the time this work was commenced the earliest known articulate Brachiopod had been described under the name of Orruis, and without having the knowledge or means to verify or disprove the character of this fossil, the genus ORTHIS was adopted for the basis of discussion. Had these older forms been better known, the order of the work might have been somewhat modified. The other associated and succeeding genera have been taken up and treated after the same idea as in Ortuts; limiting the discussion to those which seem to be a natural result of the modification of certain essential organic features characterizing the earliest forms of the orthoid type. Following this order and method we pass through all the Or7ruin#, the strophemenoid and streptorhynchoid forms in their varied aspect and modifi- cation, and through the lepteenoid forms to Cuongres and the Propuvcrinx proper, with which the series seems naturally to end. All the spire-bearing forms, all the Raywcnonettip# and Penramerip# as well as the terebratuloid forms have been left out of consideration in the present volume, believing that a more natural and useful classification will be found in the present adopted order and arrangement of the genera. Chapters upon the classification and broader relations of the genera are given at the conclusion of the two principal divisions of the work. The succeeding part ii of volume VIII will embrace the discussion of the genera under the several groups just mentioned, and they will be treated essentially in the same manner as in the present volume. The work on the second part is already far advanced; a large amount of material has been accumulated for study ; thirty- six plates have been lithographed, a considerable number of drawings have been made and a large amount of manuscript has been prepared. During the interval of more than twenty years from its commencement, ereat progress has been made in the study of both genera and species of the Brachiopoda. The late THomas Davipsoy, LL. D., of Brighton, whose life had been devoted to the study of these organisms, living and extinct, made important contributions to our knowledge up to the time of his death in 1885. Hssays PREFACE. xl toward the structure and classification of the genera were made by ZIrret, (utert and Waacen, and communications of no little importance relating to structural characters of genera and species, appeared from all quarters of the scientific world. The multiplicity of these communications is indicated in part by the biblio- graphic tables presented in this volume; they also show the wide-spread inter- est in the Brachiopoda, not only among students of biology, in their structure, morphology and taxonomy, but among geologists, in their value as stratigraph- ical indices. American students have heretofore labored under a disadvantage in the irregular diffusion of the literature of the Brachiopoda. Much of the European literature is inaccessible except to those working in the vicinity of extensive libraries; the American literature is so scattered through scientific periodicals, proceedings of various societies, etc., as to be frequently inaccessible. Furthermore, while the more general treatises of Zirre, and Gintert may be in the hands of many, the greatest of all works upon the subject, that of Taomas Davinson, is beyond the reach of but a very few. With this volume, therefore, is presented, especially to American students, the first part of ‘An Introduction to the Study of the Genera of the Paleozoic 3 Brachiopoda,” a work not conceived upon the plan of any of its predecessors, but designed to set before the student the present condition of our knowledge of these genera, with such discussions and illustration as will serve most clearly to indicate what progress has been made in our knowledge of these organisms and in what directions much still remains to be done. In the preparation of this work every effort has been made to bring under close and careful scrutiny all obtainable material representing the Brachiopoda. The collections of no single institution or individual could furnish the speci- mens requisite for this undertaking, and recourse has been had to all sources of material within reach. The collections of private individuals as well as of public institutions have been placed at the disposal of the work, and but for such aid it could not have been presented in a creditable form. My acknowledgments are especially due to Sir Wituram Dawson, Principal of McGill University, Montreal, Canada, for specimens and valuable informa- X1V PREFACE. tion; to Mr. G. F. Marruew, of St. John, N. B., for the use of fossils of the St. John group, and for valuable information concerning them; to Hon. A. R. C. Setwyn, Director, and to Mr. J. F. Wurreaves, Paleeontologist, for the use of many typical specimens from the Museum of the Geological Survey of Canada. Also to Mr. W. R. Biuines, of the Department of Public Works, Ottawa, Canada, and Mr. H. M. Amt, of the Geological Survey. From Mr. Tuomas A. Greenz, of Milwaukee, Wisconsin, I have received most important material from the Niagara group of Wisconsin; from Dr. Josua Linpant, Curator, and from the Trustees of the Illinois Museum of Natural History, the free use of its collections ; from Prof. C. L. Herrick, of Chicago, the use of his typical collection of the Waverly group; from Prof. James M. Sarrorp, of Nashville, Tenn., interesting material from his collections which have been utilized in the illustration of the Orruinx. To Prof. J. S. Newperry, I am indebted for the free use of his very interesting collections, especially of the Carboniferous fossils ; to Prof. Epwarp Orron, for his liberality in permit- ting the free access to the collections of the Geological Survey of State of Ohio; to Prof. G. C. Broapugap, of the University of Missouri, for the use of many in- teresting forms of Carboniferous fossils; to Rev. Joun Bennerr, of Kansas City, for the use of very interesting Coal Measure fossils, especially of the genera Dersya and Entreteres; to Prof. Samus, Catviy, of the University of lowa, for his liberal aid toward the illustration of the Silurian and Devonian Brachiopoda of Iowa; to W. C. Eaan, of Chicago, for the use of some interesting forms of Carboniferous fossils, and to Dr. C. Rominaer for his liberal and intelligent con- tributions to our knowledge and means of illustration of the Brachiopoda, an obligation beginning as far back as 1863. From the American Museum of Natural History, through Prof. R. P. WHITFIELD, specimens representing many genera and the types of many species have been received ; from Prof. J. P. Lesney, State Geologist of Pennsylvania, a series of inarticulate Brachiopods from that State; from Mr. Caarues D. Waxcorr the use of specimens and information concerning the same; from Prof. James R. Eaton, of William Jewell College, Missouri, during many years, the use of specimens and for much intelligent information ; from Rev. H. Herzer, the ¢ ua PREFACE, XV use of some interesting specimens of recent collection and information concern- ing certain horizons in the Lower Carboniferous strata, and also the abundant ma- terial of his earlier collection ; from Prof. E.W.Ciaypotn, the use of specimens, as well as information concerning the geological relations of certain species ; from Pres. E. 8. Brartnerp and Prof. H. M. Srgty, of Middlebury College, Vt., the use of specimens from the Calciferous horizon, which have since been donated to the State Museum ; from Prof. Gro. H. Perkins, of the University of Vermont, the use of specimens; from E. HE. Texter, of Milwaukee, Wis., and F. A. Sampson, of Sedalia, Mo., similar favors. Acknowledgments are further due to Mr. F. A. Buratr, of Sedalia, Mo., and Dr. J. H. Brirrs, of Clinton, Mo., for the use of specimens and especially for a collection of Choteau limestone fossils from the former; also to W. H. R. Lyxens, S. J. Hare, F. W. MclInrosu, of Kansas City, for specimens of Coal Meas- ure fossils; also to Prof. THomas B. Srowertt, of Cortland (now of Potsdam), N. Y., W. L. Brownett and D. S. Caatriztp, of Syracuse, and E. B. Knapp, of Skaneateles. To Prof. B. K. Emerson, of Amherst, Mass.; to Dr. C. KE. Brecuer, of New Haven, Conn.; and to E. O. Utricu, of Newport, Ky., thanks are due for specimens and information ; also to W. T. Knorr, of Lebanon, and Mr. E. C. Went, of Frankfort, Ky.; to Prof. Witttam Lrssey, of Princeton, N. J., through Morirz Fiscurr; Prof. Joserpx Moors, of Karlham College, Richmond, Ind.; to Col. C. C. Grant, an old and valued correspondent, and Mr. Witttam TuRNBULL, of Hamilton, Ontario, and to Mr. B. KE. Waker, of Toronto, for speci- mens from the Niagara and Hudson River groups; to Professors Oniver Marcy, of Evanston, Ill., Epwarp M. Sueparp, of Springfield, Mo., W. H Barris, of Davenport, Ia.,and S. S. Gorsy, State Geologist of Indiana; to L. A. Cox and D. G. Anprrson, of Keokuk, Ia., for brachiopods of the Keokuk group, presented by them to the State Museum; to R. R. Row sy, of Curryville, Mo.; to Miss Mary E. Houmns, of Rockford, Victor E. Puituies, of Olney, and J. H. Soutn- WELL, of Rock Island, and to W. R. Heap, H. H. Hinpsnaw, and Vicror C. Atpsrson, of Chicago, Illinois. Among foreign friends and correspondents, my first acknowledgments are due to the late Tuomas Davipson, of Brighton, England, for many years of personal Xv1 PREFACE. friendship and intimate correspondence relating to scientific questions, and especially to the Brachiopoda. The pages and illustration of this volume will bear testimony to the knowledge derived from this eminent source. Also to Dr. ‘Cu. Tscurrnyscuew and Dr. Fr. Scumipr, of St. Petersburg, Russia; to Prof. E. Kayser, of Marburg, Germany; to Miss Acnes Crane, of Brighton, England; Dr. D. P. @ntert, of Laval, and Prof. Cuartes Barrots, of Lille, France; to Dr. G. Linpstr6m, of Stockholm, Sweden, and to Mr. Joun Youne, of Glasgow, Scotland, acknowledgments are especially due. The lithographic plates accompanying this work have been drawn on stone by Mr. Puitie Asi, whose accurate and artistic execution of similar work is already known to the students of these volumes. The original drawings of the earlier plates were mostly made by Mr. R. P. Wurrrtetp and the late Mr. F. B. Mrgx; the drawings for the later plates was begun by Mr. E. Emmons, whose services were subsequently supplemented by the skillful and beautiful work of Mr. Guoree B. Simpson. To Mr. Cuartes ScuucuEert, my private assistant, this volume owes much. His critical knowledge of the species of American Brachiopoda, and his famil- iarity with the literature pertaining to them, as well as his unequaled collec- tion of fossil Brachiopoda, have all been placed at the disposal of the work with the devotion characteristic of the student. To him is due the fullness of the bibliographic tables, which afford virtually a complete summary of American literature upon these genera. To Prof. Joun M. Crarxs, Assistant Paleeontologist, I am especially indebted for his faithful and appreciative devotion to the accomplishment of this under- taking. On the resumption of this work in 1888, Mr. CLarke was appointed my Official assistant, and he entered at once into sympathy with my plan, and became an enthusiast in the study of the Brachiopoda. To him I am indebted for carrying out in its details, the spirit of my conception to a degree of com- pletion which I had not anticipated. JAMES HALL, Apany, May, 1892. State Geologist and Palaontologist. a R Ket jotear INTRODUCTION TO THE STUDY OF THE GENERA OF THE PALAOZOIC BRACHIOPODA. BRAN CIELO OID IN IN ANISM ING [Oa vecr oes Valves inarticulated ; intestine terminating in an anus on one side of the body; shell substance largely phosphatic. Tue foregoing characters bring into association a well defined assemblage of these organisms, but, while generally applicable throughout the group in ex- pressing the fundamental distinctions from the more abundantly developed Bracutopopa ArticuLata, there often appear, in forms which cannot be separated from such association, tendencies to transgress these limitations im various directions. For example, articulation of the valves was approached, if not effected, in the linguloid BarrorseLta, in SponpyLopotus, and, perhaps also, in Neopotus and Trimerenta. In Crania, according to the determination of Joustn,* the anus opens in the median line of the body; and in various genera, Cranta, Puotwors, TRIMERELLA, etc., there is evidence that the substance of the shell was essentially, or altogether calcareous. We have preferred to adopt for this division of the Brachiopods, Professor Houxtey’st term, Inarricutata, which has the advantage of euphony and sim- plicity. Other writers have made use of terms with different significations, all * See under genus CRANIA. + An Introduction to the Classification of Animals, p. 116. 1869. 2 PALZHONTOLOGY OF NEW YORK. having precisely the same scope. Professor Owrn,* in 1858, proposed the term LyopoMaTa (Aéw and xéyua), essentially the Greek equivalent of InarticuLata, and of Bronn’st Ecarpines. The last named author also suggested the term Pievropyeta, derived from the lateral position of the intestinal perforation ; while Kine’s term, TRETENTERATA,t indicates that the existence of an anus is to be regarded as the essential character. The use of Family designations in this group would be attended by embar- rassments so serious, that it has seemed preferable to avoid them altogether. The present state of our knowledge fully justifies this position. Genus LINGULA, Brueurmre. 1789. PLATE I, FIGS. 1-34; AnD PLATE IV Kk, FIGS. 5-13. 1789. Lingula,§ Brucuizre. Hist. Natur. des Vers Testacés. 1798. Pharetra, Bouren. Mus. Bolt. 1806. Lingularius, Dumérizr. Zoologie Analytique. Lingula, of authors generally. ( Glossina, Puttires, 1848. Mem. Geol. Surv. Great Britain, vol. ii, pt. 2, p. 370. Glottidia, Daut, 1870. American Journal of Conchology, vol. vi, p. 157. Dignomia, Haut, 1871. Imperfectly known Forms among the Brachiopoda. 1839. Lingula, Conrap. Second Ann. Rept. Palsont. Dept. N. Y. State Geol. Surv. 1842. Lingula, Vanuxem. Geology N. Y., Rept. Third District. 1842. Lingula, Emmons. Geology N. Y., Rept. Second District. 1842. Lingula, Conrav. Jour. Acad. Nat. Sci. Phila. 1843. Lingula, Hatt. Geology N. Y., Rept. Fourth District. 1844. Lingula, OwEN. Geol. Rept. Iowa, Wisconsin, and Illinois. 1847. Lingula, Hay. Paleontology N. Y., vol. i. 1847. Lingula, Dana. American Journal of Science. 1851. Lingula, Hatt. Foster and Whitney’s Rept. Geol. Lake Superior. 1852. Lingula, Hart. Paleontology N. Y., vol. ii. 1852. Lingula, OWEN. Geol. Rept. Iowa, Wisconsin, and Minnesota. 1852. Lingula, F. Ramer. Kreidebildung von Texas. * Encyclopedia Britannica, 8th Ed., vol. xv, p. 301. + Die Classen und Ordnungen des Thierreichs, p. 301. 1862. t Annals and Magazine of Natural History, vol. xii, p. 15. 1878. § The synonymic lists accompanying these discussions are intended to give, first, the more important names under which the genera have been mentioned by European and American writers, followed by a table of references to notices in American literature of the genera or their species. Under the lesser groups, the lists are not thus divided, but will be found to contain all the important references necessary for the use of the student. 1856. 1856. 1857. 1858. 1858. 1859. 1859. 1860. 1861. 1862. 1862. 1862. 1863. 1863. 1863. 1865. 1865. 1866. 1867. 1868. 1868. BRACHIOPODA. Lingula, Brunes. Canadian Naturalist and Geologist. Lingula, Emmons. American Geology. Lingula, Cox. Geological Survey of Kentucky, vol. iii. Lingula, Meex and Haypen. Proc. Acad. Nat. Sci. Phila. Lingula, Saumarpv. ‘Trans. St. Louis Academy of Sciences. Lingula, Brutines. Canadian Naturalist and Geologist. Lingula, Hatt. Paleontology N. Y., vol. iii. Lingula, Haut. Thirteenth Rept. N. Y. State Cab. Nat. Hist. Lingula, Bruuines. Canadian Naturalist and Geologist. Lingula, Haut. Fifteenth Rept. N. Y. State Cab. Nat. Hist. Lingula, Bruurnes. Paleozoic Fossils, vol. i. Lingula, Wuirr. Proc. Boston Soc. Nat. Hist. Lingula, Haru. Sixteenth Rept. N. Y. State Cab. Nat. Hist. Lingula, Haut. Trans. Albany Institute. Lingula, WincHEuL. Proc. Acad. Nat. Sci. Phila. Lingula, Wurre. Proc. Boston Soc. Nat. Hist. Lingula, Bruunes. Paleozoic Fossils, vol. i. Lingula, Bruunes. Catalogue Silurian Fossils Anticosti. Lingula, Hatt. Palzontology N. Y., vol. iv. Lingula, Murx. Trans. Chicago Academy of Sciences. Lingula, Merk and.WortnHen. Geological Survey Illinois, vol. ili. 1869(2) Lingula, Wincuett. Proc. American Philosophical Society. 1872. 1873. 1873. 1874. 1874. 1874. 1875. 1875. 1875. 1875. ‘1875. 1878. 1879. 1879. 1880. 1880. 1881. 1882. 1884. 1884. 1884. 1884. 1884. 1885. 1887. 1888. 1889. 1889. Lingula, Mnex. Rept. Paleontology Eastern Nebraska. Lingula, Haut. Twenty-third Rept. N. Y. State Cab. Nat. Hist. Lingula, Merx and WortHen. Geological Survey Illinois, vol. v. Lingula, Ravusun. Bull. Buffalo Soc. Nat. Hist. Lingula, Wuirr. Wheeler’s Expl. 100th Meridian. Lingula, Bruurnes. Paleozoic Fossils, vol. ii. Lingula, Nicnotson. Rept. Paleontology Province of Ontario. Lingula, Merk. Geological Survey Ohio; Palzeontology, vol. ii. Lingula, James. Cincinnati Quart. Journ. Science. Lingula, Hatt and Wuirrienp. Geological Survey Ohio; Paleeontology, vol. ii. Lingula, 8. A. Mituer. Cincinnati Quart. Journ. Science. Lingula, Rarupun. Proc. Boston Soc. Nat. Hist. Lingula, Kmerson. Geol. Frobisher Bay, in Nourse’s Narr. Hall’s Arctic Expedition. Lingula, Hatt. Descrip. New Spec. Fossils from the Niagara Group. . Lingula, N. H. Wincuett. Geological Survey Minn., Eighth Ann. Rept. Lingula, Wuirrietp. American Journal of Science. Lingula, Hatt. Eleventh Ann. Rept. State Geologist Indiana. Lingula, Wurrrretp. Geology Wisconsin, vol. iv. Lingula, H. 8. Wiru1ams. Bull. No. 3, U. S. Geological Survey. Lingula, Warren. Thirteenth Ann. Rept. State Geologist Indiana. Lingula, WortHen. Bull. No. 2, Illinois State Mus. Nat. Hist. Lingula, Waucorr. Paleontology Eureka District. Lingula, RincuEBere. Proc. Acad. Nat. Sci. Phila. Lingula, Cuarke. Bull. No. 16, U. 8. Geological Survey. Lingula, Wuirraves. Geol. and Nat. Hist. Sury. Canada. Lingula, Herrick. Bull. Denison Univy., vol. iv, pt. 1. Lingula, Waucotr. Proceedings of United States National Museum 1888. Lingula, Nerrerrora. Kentucky Fossil Shells. 4 PALEONTOLOGY OF NEW YORK. Driacyosis. Shells sub-equivalve, equilateral; elongate-ovate, sub-quadrate or sub-triangular in outline; broad over the pallial region, cardinal slopes more or less conspicuous; slightly gaping at both extremities. Brachial or dorsal valve somewhat the shorter, and with a slightly thickened hinge-line. Surface of the shell smooth, or concentrically and radiately striated. Animal attached by along, muscular pedicle protruding from between the beaks of the two valves. Muscular impressions numerous, but usually in- distinct. In the recent species they are twelve in number upon each valve, and are somewhat unsymmetrical in their arrangement. They may be designated as follows: The uwmbonal impressions (g), produced by a single muscular band passing directly across the cavity of the shell near the beaks, and by their contraction opening the valves; the lateral impressions, which are produced by three pairs of muscles, the anteriors (j) passing from near the lateral boundaries of the visceral area on the pedicle-valve, forward to the anterior extremity of this tract on the brachial valve; the middles (k) passing in just the opposite direction, from the anterior region of the pedicle-valve to the lateral region of the brachial; the ezternals (2) passing from the ante-lateral region of the pedicle-valve to the post-lateral region of the Fig. 1. Lingula anatina, after HANCOCK. Pp, pedicle; g, umbonal muscle; h, cen- trals; z, transmedians; Jj, %, J, laterals (j, anteriors, /,middles,/, externals); e, heart; 0, mouth; @, alimentary canal; z, anus. brachial valve, these muscles serving to move the valves forward and backward. The central impres- sions (h) are produced by a single pair of muscles extending across the ante- lateral region of the visceral area, and by the contraction of these, the valves are closed. The transmedian impressions (7), are made by a triple muscle, one band of which is on one side the visceral area, the other two on the other side, the two lateral components crossing each other in passing from the posterior region BRACHIOPODA. 5 of the pedicle-valve to the medio-lateral region of the opposite valve. By the action of these muscles the animal is able to slide apart the anterior and posterior extremities of its valves.* The muscular region in each valve is sur- rounded by the parietal bands (6), which leave more or less distinct impressions upon the shell. The anterior internal surface of each valve bears traces of two strong pallial sinuses, which nearly meet in the axial line before reaching the anterior margin. In front and behind are radiating vascular markings. Shell substance composed of alternating lamelle of chitinous and calcareous material. Type, Lingula anatina, Lamarck. Oxsservations. Few of the larger genera of the brachiopoda form so integral a group and present so well defined limitations as the genus Lineuna. Not- withstanding, however, the compactness of the genus, the discrimination of paleozoic species is frequently attended by very great embarrassments, arising from the tenuity of the shell, its lability to distortion in process of fossilization, the general similarity in the matter of external ornamentation, and the usual obliteration of the definition of the muscular scars by maceration or from the character of the matrix. Primarily, the shells of paleeozoic Lingulas present two extremes of varia- tion in outline, (@) an acuminate or sub-triangular form, in which the rostral area is very narrow, with long, sloping post-lateral margins, and a rounded or transverse anterior margin; (0) a sub-quadrate form, with the posterior or rostral margins converging toward the beak. The passage-forms between these extremes present outlines varying from ovate to elliptical, and here the great majority of species is to be assigned. While all these variations in form have maintained a contemporaneous existence in palaeozoic time, the acuminate type (a), prevailed both numerically and specifically in the earlier faunas (L. acumi- nata, in the Calciferous sandstone; L. attenuata,in the Llandeilo; L. crumena, in * Among authors there has been a confusing variety of nomenclature for the muscular system in Linauta. The one that is used here is proposed by Professor Wiiti1Am Kina, and, in its simplicity, has claims for adoption. 6 PALAONTOLOGY OF NEW YORK. the Llandovery; L. Daphne, L. riciniformis, in the Trenton; L. Rouaulti, L. Hawkii, in the Budleigh-Salterton pebbles [Lower Silurian]; Z. perovata, in the Clinton; L. cuneata, in the Medina sandstone; L. spatiosa, in the Lower Helderberg), diminishing during the Devonian (L. Leena, in the Hamilton), and reaching the close of the Palseozoic with a very meager representation (L. Scotica, L. flabellula, in the Carboniferous); and of the various types of outline, this is the only one not represented among living species of the genus. The generic term Lineuua, like many other names among the fossil brachi- opods, has long been a receptacle for various fossils, which, in the absence of knowledge of their internal characters, have been assumed to be con- generic. Recent observers have, however, made great progress toward a cor- rect understanding and limitation of the group. Many species of acuminate form originally referred to Linauta, have been found to differ so distinctively, in essential features, from the type species, L. anatina, that the erection of various other generic groups has been necessary; e. g., LincuLELya, Salter, Liy- cuLEPIS, Hall, Guossina, Phillips, ete. To some of these newer genera, probably belong most of the species from the primordial faunas, which have been described as “ Lingua,’ a doubt resting upon all the species thus referred, whose interior markings are not known. Thus, L. ampla, Owen, L. Winona, and L. Mosia, Hall, from the Potsdam sandstone of Wisconsin, have the external characters of LineuLa, and must, of necessity, be regarded as members of the genus, until the difference has been demonstrated from internal characters. Likewise, in the British primordial faunas are the species, L. sguamosa, Holl, L. pygmea, Salter, and L. petalon, Hicks, of which we have still to learn the true generic relations. The fact that as far as the internal characters of the species of the earliest faunas have become known they have shown generic differences from LineuLa, may, to a certain degree, justify the temporary refer- ence of the species mentioned to some other group. This genus has been most remarkable for its wonderful adaptability to change in the conditions of life through immeasurable lengths of geological time, and, though in its strict limitation it may not have been represented in the earliest BRACHIOPODA. 7 faunas appearing on the earth, its persistence in time is nevertheless unequaled by that of any other known genus of organisms. The paleozoic Lingulas, sensu stricto, have not shown variations of sufficient importance to permit a thoroughly satisfactory subdivision of the genus. As the interiors and muscular scars of different species become known, they re- veal a closer alliance with one another, and with the recent type of the genus, than had been suspected. There is a growing tendency among authors to remove certain species from this genus to LINGULELLA on account of an apparent inequality in the valves of the shell, accompanied by a cardinal area on the pedicle-valve, which seems to be grooved or depressed from the apex forward. Great care is needed in the accurate determination of these features. The type species, Lingula anatina, has not only gaping and slightly unequal valves, but the pedicle-valve has a distinct cardinal shelf or area, divided longitudinally by a depression widening from the apex anteriorly, and termed by Kine* the “deltidium.” This, accord- ing to Professor Kine, is usually not well developed, and in the average speci- mens of L. anatina found in museum collections, ap- pears to be partially or quite wanting, from accidental causes. The deltidium is bounded at the sides by elevated ridges, which, at the anterior ends, are each developed into a small callosity. “The ridge-callosi- pg. 2, zinguta anatina ; cardinal area of pedicle-valve, after KING. a, del- tidium; 0, deltidial ridges; c, deltidial callosities ; d, areal borders. ties are no doubt insignificant; nevertheless they appear to be the rudiments of important structures. Apparently they have become so far developed in Lingula Lesueuri, as to serve to articulate the valves. If Iam correct . . . . . this species cannot belong to the genus in which it has been placed.”; In the opposite or brachial valve is a slight area without a deltidium, but bearing concentric growth-lines, and a very faint longitudinal groove. It is to be expected that we shall find similar features more or less devel- oped among the fossil Lingulas. The broad, depressed deltidium of L. anatina * Annals and Magazine of Natural History, July, 1873. t Kine, loc. cit., p. 13. 8 PALHONTOLOGY OF NEW YORK. is not to be confounded with the deep pedicle-slit in Lineutetta. Furthermore, a slight longitudinal displacement of the valves before, or while undergoing fossilization, will frequently exaggerate the normal extension of the umbonal region in the pedicle-valve, beyond that in the opposite valve. We are dis- posed to consider the current reference to LinauLenia of several well-known American species, e. g., L. lowensis, Owen,* L. Covingtonensis, Hall and Whit- field} L. Norwoodi,t James, L. Vanhornii, Miller, as incautious, and feel that, in general, these are more safely left under the original genus. Two of the species named, viz., L. lowensis and L. Vanhornit, have muscular impressions comparable with those of L. anatina, and of widely different character and arrangement from those in the genus LINGULELLA, Living Lingulas, are known to form a tube about the pedicle by the agglutination of grains of sand or other sedimentary débris, after the manner of Tubifer and other forms of Chetopod Annelids. (See accompany- ing figure of Lingula pyramidata,§ Stimpson, after Morse, which shows this tube, as well as the effect of the action of the sliding or ¢ransmedian muscles in swinging the valves laterally asunder.) FIG. 3. Lingula(Glottidia) Andebarti. After MORSE. * Lingulella Iowensis, Whitfield, Geol. Wisconsin, vol. iv, p. 242. 1883. + Mx. 8. A. Mitier, in his ‘‘ Catalogue of the Fossils found in the Hudson River, Utica Slate and Trenton Groups, as exposed in the South-east part of Indiana, South-west part of Ohio, and Northern part of Ken- tucky”; Tenth Ann. Rept. Geol. Sury. Indiana, says, on page 19, under the heading Lineura: ‘ All the species referred to this genus” [in the groups mentioned] ‘belong to Lingulella;” and in Mr. J. F. JaMEs’ “Catalogue of the Fossils of the Cincinnati group,” 1881, in addition to the species mentioned above (ex- cepting L. Covingtonensis), L. attenuata, Sowerby, and L. riciniformis, Hall, are referred to the sub-genus LINGULELLA. t This species belongs to the genus Lincuops. § Glottidia Audebarti, Broderip. Davinson, Trans. Linnean Society, Second Ser., Zoology, vol. iv, part 3, p. 223. BRACHIOPODA. i) The retention, in the fossil state, of the pedicle, is a rare occurrence. Of palzozoic species, Mr. Davipson* has figured an example of L.? Lesueur’, in which the impression of this organ is very distinctly shown. More recently, Mr. Watcorry has described a beautiful example of L. equalis, Hall, in which the narrow arm is seen pro- truding from the aperture in the cardinal area. By the favor of Dr. J. 8S. Newserry, we have been allowed to figure a specimen from the Waverly sandstone at Oil City, Penna. (see Plate IV x, fig. 7), in which the pedicle is also distinctly visible. The species tingutaequatis, Hall, Lingula? Lesueuré, Rouault. e = ° x s With pedicle. With pedicle. is the one identified as L. Scolica, Davidson, After WALcorr. After DAVIDSON. by the Ohio geologists, and more recently described by Mr. Herricxi as L. Waverliensis. In regard to the myology of the paleozoic Lingulas, we have satisfactory evidence that the arrangement of the muscles did not differ widely from that in recent members of the genus. It is, however, not often that a paleozoic specimen is found which has retained upon the surface of the shell, or left upon the matrix, traces of the delicate muscular scars; and in such instances usually only the stronger impressions are discernible. A few examples have been figured by recent American writers, which retain, in exquisite detail, not only the mus- cular, but also the pallial impressions of the shell. Of these, one is a brachial valve of the L. Whitii, of Watcorr, figured in his Paleontology of the Eureka District ;§ another, an internal cast, representing the impressions on both dorsal and ventral valves of L. Elderi, Whitfield, figured by the author first, in the Amer- ican Journal of Science,|| and subsequently, in the Report of the Geological Survey * Brachiopoda of the Budleigh-Salterton Pebble-bed, p. 362, pl. xl, fig. 16. t Proceedings of the United States National Museum, for 1888, p. 480, fig. 3. t Bull. Denison Uniy., vol. iv, pt. 1, p. 18, pl. iii, fig. 1. 1888. § Page 109, pl. xiii, fig. 3, and pl. xxi, fig. 19. 1884. | Vol. xix, p. 473. 1880. 10 PALHIONTOLOGY OF NEW YORK. of Wisconsin.* Upon the first plate of this volume are given, in addition to copies of the figures named, a number of illustrations representing these impres- sions in different degrees of completeness; especial attention may be directed to the figures of L. punctata, L. Procteri, L. densa, and to those of L. lamellata, upon Plate IV. (See, also, the figures of L. Lewisi, Sow., given by Davipson,f and the accompanying text illustrations of extremely well preserved internal casts of L. Melie [brachial valve], and L. paracletus, sp nov. [pedicle-valve].) There has been a considerable diversity of opinion among authors, in regard to the special functions of the various muscular bands in Lineuna. Few in- vestigators have brought to the study of this subject the clear insight and incisive judgment of Professor Witt1am Kine, whose nomenclature of the mus- cles, we have preferred to adopt. The first strong impression arising from the comparison of these ancient forms with the type-species is that in the former, the dorsal scars of the central muscles (h) are relatively much the larger, and are situated somewhat posteriorly, apparently encroaching upon that portion of the visceral chamber which, in L. anatina, is occupied by the essential organs of the - animal. This apparently great size, however, is somewhat illusory, = as undoubtedly a portion of these large scars is due to their contin- ued advance as the shell increases in age, and probably at no time in the mature life of the animal did these muscular bands, at their or- Tingula, anatina alter DAVIDSON: Fic. 6. Pedicle-valve. Fig. 7.¢ Brachial valve. Stan 1 ] i, b, parietal scar ; g, umbonal muscle; #, transmedians, h, centrals; 1g1n and insertion, cover the entire : j, &, 1, laterals (J, Anlenione: k, middles; J, externals). * Vol. iv, p. 345, pl. xxvii, figs. 3-5. 1882. + Monogr. British Silurian Brach., pl. iii, figs. 5, 6. { Davipsoy’s figures are diagrammatic copies of the more elaborate illustrations given by Kine. In the process of copying it is evident that fig. 7 has been reversed, and the position of the double and single muscular bands of (i) inverted. BRACHIOPODA. 1 scars. Thesame may be said of the other scars, all of which show something of this progressive increase in size. The impressions which appear to be most gener- ally retained among the fossils are the anterior laterals (j) of the brachial valve, and the middle laterals (k) of the pedicle-valve. These lie in the ante-median portion of the valves, and, in their progress forward, have left long, conspicu- ous tracks which follow the axis of the shell. The separate members of these pairs of impressions are not always, or even often, to be distinguished, the long axial impression accompanied by the ante- rior portions of the broad centrals being usually all that is visible of the mus- cular scars. The subdivision and asymmetry of these scars in J. anatina has been determined only by the aid of the attached muscular bands. Without their assistance it would prove difficult, if not impracticable, to ascertain their exact limitations, merely from the impressions upon the shells. This will, to a certain degree, be made evident by comparing Professor Ktve’s figures with those of the same species given on Plate I; in the latter drawings the scars have been somewhat emphasized, but it is impossible to resolve, with any degree of accuracy, the compound lateral and transmedian scars (4, /, 7, in the brachial, 7, 2, in the pedicle-valve). Nevertheless, in the brachial valve of L. Whitii, the com- pound lateral scar is quite distinct, and the umbonal (g) impression well defined. On the brachial valve of L. Hider?, Mr. Wurrrietp has shown the former to be even more clearly defined than in L. Whitt, and the umbonal scar to be un- usually large. In both these species, the laterals and transmedians are situated considerably nearer the umbonal region than in L. anatina. The pedicle-valve of L. Elderi shows the transmedian scars, which are represented as two on each side, the anterior of which is regarded by the author as the scar of the b) “posterior adjustors” (transmedian) and “anterior adductors” combined. Lingula punctata shows comparatively. broad muscular scars in this region, but it has been impossible to resolve them satisfactorily. The umbonal scar also, appears on the pedicle-valve of L. Elderi. A species of Lincuta from the Cuyahoga shale at Johnstown, Chardon, and elsewhere in Ohio, which has usually been confounded with the common L. Melie 12 PALHIONTOLOGY OF NEW of these beds, but is described in the concluding pages of this work as L. paraciletus, sp. nov., has afforded the most complete and satisfactory representation of the system of muscular scars. The pedicle-valve here figured is drawn from a cast of the interior, which shows not only the centrals (/), middle laterals (&), but the dis- singutaparactetus, sp. nov. enn at, tinctly specialized outside laterals "0" °* Peeve ae mea nag (1), anterior laterals (/), the transmedians (7), and the great umbonal (g). Even the asymmetry of the transmedians (¢) is apparent in the unequal size of the impressions, that on the left in the figure (corresponding to the right, when looking into the interior of the valve) being noticeably larger than its correlate. In the brachial valve, the scars are essentially like those in the corresponding valve of L. Melie, shown in the accompanying figure, but are not placed quite so far back. Here the laterals (/, 4) and transmedians (7) are coalesced, and show a tendency to spread transversely over the visceral region, a feature sometimes noticeable in other paleeozoic species, and probably of similar nature to that seen in Barroisella subspatulata (Plate I, fig. 16). As far as the vascular markings of the brachioccele in the fossil species have been observed, they appear to have been in full agreement with those of the living type. In L. Whitii, L. Elderi, L. punctata, L. cuneata, and L. lamellata the large pallial sinuses are to be seen passing forward from the parietal band, or the position of the compound lateral scars, approaching each other until they nearly or quite meet in front. The outer-ramifications from these large trunks, and, in L. Elderi and L. cuneata, the inner also, are discernible. In the brachial valve of L. Elderi are seen the vascular impressions of the pleurocoeles, which lie in the post-lateral portion of the internal cavity, outside the parietal band. In L. Procteri and L. paracletus, the anterior vascular branches appear to radiate from the edge of the central muscles, as though the pallial trunks ~ BRACHIOPODA. 13 passed closely about their insertion, a feature which requires confirmatory evidence. In so far, then, as the impressions upon the shell, left by the soft parts of the animal are concerned, we find a close correspondence in the existing and palee- ozoic members of this genus. We turn now to a consideration of the septal markings on the interior of these shells. When the soft parts are entirely removed from the shell of L. anatina, the pedicle-valve shows a broad, low, longitudinal ridge, whose margins are sharply incised along the posterior portion, but become elevated with the ele- vation of the entire ridge anteriorly. This ridge terminates in front of the center of the shell, and bears, at its excavate extremity, the impressions of the middle-lateral muscles, being buttressed on either side behind these, by the large scars of the centrals. From the posterior extension of this ridge diverge two more or less distinct longitudinal callosities, which are the inner boundaries of the transmedian impressions, or the raised margins of the parietal scars. In the opposite, or brachial valve, a longitudinal ridge is more or less developed toward the posterior portion of the shell, but becomes flattened over the central visceral region, whence it is produced much further forward than in the opposite valve, and is sharply elevated. Its terminal portion separates the ante- rior lateral scars, directly behind them lying the central muscular impressions. With these features in mind, we must expect to find the true paleozoic Lingulas showing evidence, to a certain degree at least, of such internal ridges and cal- losities. In regard to these shell-ridges, Kine has said: “ The muscles, including the parietals, produce scars, often well seen in the valves of recent Lingulas. The scars are occasionally lable to become raised at their margin, giving them the appearance of individualized muscular fulera or myophores. A specimen before us has the scar of one of the post-lateral parietals with its inner margin completely raised in the form of a plate. Such cases are evidently of abnormal formation ; but they explain the origin of what may be assumed as normal cases—for example, Lingula albida, in which there are two of the same kind of plates.”’* * On Some Characters of Lingula anatina. p. 8. 14 PALHIONTOLOGY OF NEW YORK. On the basis of the above mentioned peculiarity, Mr. Dati has separated such forms as L. albida from the genus Linauta, under the generic term Grorrrpi,* 7. ¢., shells in which the pedicle-valve bears two diverging parietal ridges and the brachial valve a median ridge of about the same length. Representatives of Mr. Dauw’s genus have been regarded as confined to liv- ing species,t and as representing the genus LineuLA in FIGs. 10, 11. n nas . Glottidia Palmeri, after DAVIDSON. American seas. Fig. 10. Pedicle-valve. Fig. 11. Brachial valve. The name Dienomia was proposed in 1871 for certain Devonian and Silurian species, which are characterized by a strong longitudinal septum in “one or both valves.”+ Type, Lingula alveata, Hall, of the Hamilton shales. In this species, the median septum is sometimes strong and sharp, sometimes broad and low, with raised margins precisely as in the pedicle-valve of L. anatina (see figures of the species, Plate I). In addition, however, to the median septum, L. alveata, the type species, shows distinct evidence of diverg- ing parietal ridges, and, moreover, is the only American fossil species that is known to retain these as a persistent feature. The presence of the longitudinal septum alone in some degree of development, is by no means a rare feature among the palzeozoic species, and, as before observed, specimens fre- quently give evidence of the fact that this has been partially or wholly formed by progressive accretions to the anterior or median muscular fulera. (See further on this point the observations on the formation of the platform in the Trimerellids.) Thus it has attained different degrees of development in L. quadrata of the Trenton, L. Jowensis of the Galena limestone, bp * American Journal of Conchology, vol. vi, p. 157, pl. viii, figs. 1-6. 1870. + Mr. Davipson calls attention to the close similarity apparent in Glottidia Palmeri, Dall, and Lingula? Lesueuri, Rouault, in respect to these septal ridges. (Brachiopoda of the Budleigh-Salterton Pebble-bed, p. 362.) We have just referred to Prof. Kine’s suggestion that the latter species should be placed in a distinct genus, on account of its strong deltidial callosities, apparertly adapted for the articulation of the valves, and it will probably prove a representative of the genus BARROISELLA (q. v-). { Hatz, Ou some Imperfectly known Forms among the Brachiopoda. 1871. BRACHIOPODA. 15 Procteri of the Hudson group, L. cuneata of the Medina sandstone, L. centri- lineata of the Lower Helderberg, L. punctata, L. Delia and L. densa of the Hamilton, ete. While in many cases it has not been observed and in other species is known not to exist, it must be borne in mind that all specimens of L. anatina do not show the internal ridges with equal distinctness, and that not infrequently they are all obsolescent. It will therefore be a matter of much difficulty, if it be possible, to fix upon features of permanent taxonomic value in the development of these septal ridges. In Dienomta (Z. alveata) it is an important fact that both median and lateral ridges appear to be nearly equally developed in both valves, and herein lies a distinctive difference between this form of development and that charac- terizing either Lingula anatina or Guorripia. It would not be prudent to attempt a further sub-division of Liveuxa on septal features alone, although one cannot but recognize the great differences of development in these respects. Dignomra, however, may be tentatively accorded a sub-generic value until its further rela- tion to, or divergence from LineuLa can be demonstrated. In 1848, Puittips proposed to place such forms of Lineura as L. attenuata, Sowerby, and L. crumena, Phillips, in a separate group under the designation Guossina.* The author seems not to have given a diagnosis of the characters of the division, but evidently intended to include in it a pretty well defined group of forms. Our knowledge of the internal characters of these earlier acuminate forms is very imperfect, as they have rarely given any indication of muscular impressions or septal markings, and it may eventually be advisable to separate this group from typical Lingulas, under the name proposed by Patn- tips. We must not overlook the fact that 1. cwneota has shown muscular scars having the general character of those in L. anatina, but this species deviates slightly in the sub-quadrate tendency of its outline from the group of sub-trigonal forms constituting Giossina. Mr. Davipson has also shown that similar scars exist in L. Hawkii, Rouault, a species having the broadly spatulate character seen in L. flabellulat and L. Scotica. * Mem. Geol. Surv. United Kingdom, vol. ii, pt. 1, p. 379. + For description, see Supplement. 16 PALHIONTOLOGY OF NEW YORK. We are not aware that any author has described or represented the form and size of the egg of the recent Lineuta since the publication of Profes- sor Ownn’s observations “On the Anatomy of Terebratula,’ in Davipson’s “ Introduction to the British Fossil Brachiopoda,’ 1853. On plate i of this work, figures 7, a, b,c, d and e, are given representations of the ova after impregnation has been effected, which indicate that their form in this condition is elongate-ovoid or sub-trihedral (7c). According to Lacaze-Dututers, the egg of TnectpiuM, in its’earliest observed condition, is somewhat pyriform.* Morse describes the eggs of TrREBRATULINA as “ generally kidney-shaped, though very irregular as to form and size.”’}+ As to the actual size of the ova discussed by these authors, Owern’s figures, enlarged one hundred and twenty diameters, would indicate alength of .1; mm. Morse has given no exact measurements of these bodies ; the youngest embryo in which the shell is developed, is about .5 mm. in length, and it is fair to assume that the ova are considerably smaller. On removing the shell from a specimen of Lingula lamellata, Hall, from the Niag- ara limestone at Hamilton, Ontario, in order to determine the character of the muscular scars, the interior filling, a compact, fine-grained calcareous mud, was found to be filled with minute ovoid bodies. The valves of the shell were in the normal apposition and in contact about the entire periphery. The bodies referred to (ova, as we believe them to be), vary somewhat in size and shape, their length being from .3 to .6 mm., their form elongate-ovoid or ellipsoidal. They are closely crowded together, but seldom in actual contact, the interspaces being filled, not with the mud of the sediment, but with a translucent crystalline calcite. They are most abundant wherever the pallial sinuses have extended, but in the marginal regions have been crowded inward by the intrusion of the sediment. A section of the interior of the filling shows that these bodies had evidently been set free into the perivisceral cavity, and have also found their way into the visceral region after the decomposition of the softer parts of the animal. That they are not of odlitic or foraminiferal nature is demon- * Annales des Sciences Naturelles, 4th Ser., vol. xv, p. 302. 1861. + On the Early Stages of Terebratulina Septentrionalis ; Memoirs of the Boston Society of Natural History, vol. ii, page 81, pl. i, fig. 1. See, also, Embryology of Terebratulina, op. cit., pp. 251, 252, pl. viii, figs. 1-5. BRACHIOPODA. Wf strated by a thin transverse section, which shows them to be simply opaque masses without evidence of structure save a thin transparent external cover- ing. Enlarged figures of this internal cast and of the ovoid bodies are given upon Plate IV x. On account of the extreme tenuity of the shell in the fossil Lingulas, it is difficult to ascertain its structure from sections. The shell-substance is essentially corneous, and the mineral intermixture is calcic phosphate with traces of calcic and magnesic carbonates. The organic and inorganic constituents are arranged in alternating lamelle, the former, according to Gra- TroLEt,* having a fibrous structure, and the latter being traversed by numerous microscopic canals. w, sub-cardinal sears. quently expressed «x, umbo-lateral scars. opinion of Mr. Davipson’s, abandoning his earlier views on the value of this * On the Trimerellidz, a Paleozoic Family of the Palliobranchs or Brachiopoda. By Tuomas Davip- son, Esq., F. R.S., F. G.S., ete., and Professor Witttam Kina, Sc. D. Honoris Causa, Queen’s University in Treland: Quart. Journ. Geol. Soc., vol. xxx, pp. 124-173, pls. xii-xix. 1874. 32 PALHIONTOLOGY OF NEW YORK. genus. In an appendix to their paper, the authors mentioned discussed the character of the genus LiscuLops, then known only from the interior of a single valve, and pointed out its affiliations with the Trimerellids. Of this genus also our knowledge has greatly progressed, and we have now not only an accurate understanding of the interiors of both valves of the type-species, L. Whitfieldi, but also of two other species, L. Norwoodi and L. Granti. These have furnished indisputable evidence of Trimerelloid characters, and show the first deviation in this direction from the typical Lineuna. Added to this is the genus Linautasma, recently described by Mr. E. O. Utricn, which presents another interesting and important link in the development of this family. These latter genera (and we have elsewhere adverted to the same subject more at length) are neither true Trimerellidze under the foregoing definition of this group, nor can they be properly included under the Lingulide, except as a matter of convenience in classification, and we here meet, as we often do in the study of the inarticulate brachiopods, an emphatic protest against the unnatural rigidity of any scheme of classification, requiring the alignment upon the same plane, of forms which may be, in various directions, successive and gradational. The anatomical features of these shells calling for especial attention are (1) the platform, (2) the umbonal chambers, (3) the muscular scars. The first two are treated in reference to their development and functions in another place (see page 46). The last is most remarkable for the striking specialization of the so-called “crescent,” a sub-marginal, cardinal impression, skirting the posterior area of the shell in both valves and terminating in, or just enclosing at about the middle of the sides, a prominent, sometimes compound scar. This is believed to be the impression of a strong muscular post-parietal wall, its position being quite analogous to the same feature in Lineuta. The lateral and terminal impressions are undoubted analogues of those occupying similar posi- tions in L. anatina (i, j, l, in the pedicle-valve ; /, 7, k, in the brachial), and though evidently compound, it has been hitherto impossible to resolve them into more than two distinct pairs of scars. The median impression, 7. e., that covering the surface of the platform, is readily resolvable into central, lateral, BRACHIOPODA. 33 and, usually, anterior scars; the post-median impression, indicated upon Davip- son and Kine’s figure above given, and considered by these authors as the marks of the genitalia, is, usually, extremely indistinct. Just within the cardinal margin are seen, more clearly in Rutnoso.us than elsewhere, two small, distinct scars (umbo-laterals), the function and analogues of which are not understood. Genus TRIMERELLA, Buunes. 1862. PLATE IVA, FIGS. 1-10; anD PLATE IVB, FIGS. 1-6. 1862. Trimerella, Bittincs. Paleozoic Fossils, vol. i, p. 166. 1867. Trimerella, Linpsrrém. Ofvers. af Kong]. Vetenskaps-Akad. Férhandl. No. 5, p. 253, pl. xxi. 1868. Trimerella, Linpstrém. Geological Magazine, vol. v, p. 441. 1870. Gotlandia, Trimerella, Datu. American Journal of Conchology, vol. ii, pt. 2, p. 160. 1871. Trimerella, Merx. American Journal of Science, Third Ser., vol. i, p. 305. 1871. Trimerella, Datu. American Journal of Conchology, vol. vii, pt. 2, p. 83. 1872. Trimerella, Davipson and Kine. Report Brighton Meeting Brit. Assoc. 1873. Trimerella, Hatt. Twenty-third Rept. N. Y. State Cab. Nat. Hist., pl. xiii, figs. 11-16. 1873. Trimerella, Menx. Geology of Ohio; Paleontology, vol. i, pp. 182, 183, pl. xvi. 1874... Trimerella, DAvipson and Kine. Quart. Journ. Geol. Soc., vol. xxx, p. 1438, et seq. 1875. Trimerella, Nicuouson. Rept. Paleont. Proy. Ontario, pp. 67, 68, figs. 36, 37. Diagnosis. Shell thick; outline elongate-ovate. Pedicle-valve with an erect and straight umbo, which is usually solid for the greater part of its length, but double-chambered toward its base; cardinal area very prominent; deltidium broad; deltidial ridges more or less conspicuous ; deltidial callosities slightly developed; cardinal slope well defined. Crescent sharply incised over its summit, but faint toward the sides, where it is con- nected with the broad lateral and terminal scars which are not so distinctly outlined as in the allied genera. Platform long, narrow, and strongly devel- oped; platform-vaults tubular, the dividing wall being continued as a short septum in front of the platform. Muscular scars of the platform usually ex- tremely faint, but under favorable preservation divisible into median and lateral components. Pallial sinuses faint. Brachial valve with a marginal umbo, which is much thickened in some instances, without producing a cardinal area, though making a prominent apophysis which is extended against the cardinal slope of the opposite valve. 34 PALAZONTOLOGY OF NEW YORK. Crescent as in the other valve. Platform higher than in the pedicle-valve, its vaults extending scarcely so far backward. Anterior median septum long, often reaching almost to the margin. Muscular and pallial impressions faint. Type, Trimerella grandis, Billings. Oxsservations. The species of this genus are subject to some interesting varia- tions, though, in the development of certain features within the limitations of a given species, such great differences are not as noticeable here as in Monom- ERELLA and Dinoponus. The relative size of the great cardinal area appears to be a permanent character. A tendency toward the subdivision of the umbonal cavity by a vertical septum (cardinal buttress) is apparent in all species, and constitutes an approach to the large umbonal chambers in Monomeretia. The great development of the platforms necessitates the abbreviation of the umbonal chambers, while, accompanying the obsolescence of the platforms in Monomer- ELLA, is a resultant increase in the size of these chambers.* In the brachial valve the umbo is incurved, and just beneath, or within it, is sometimes devel- oped a strong process, grooved on its outer surface. This feature is seen in T. Ohioensis, Meek and T'. Lindstremi, Dall. Messrs. Linpstr6mM, Davipson and Kine, and Datu have been disposed to regard this as a cardinal process, fitted like a tooth into an excavation at the base of the deltidium of the opposite valve. The evidence of such a process affording attachment for muscles open- ing the valves is generally wanting among the other genera, and other species of this genus; and if this process served such a function, we should expect to_ find correspondingly large and deep muscular scars upon the platform of the pedicle-valve. Our evidence on this point is rather negative, though through- * The Gotland species, 7. Lindstrami, Dall, possesses a peculiar umbonal character. The small lateral umbonal chambers are forced wide apart by the development of a median, undivided cayity, which makes the umbo hollow for its entire length. This cavity isrepresented in the figures given by Linpstrém, Davip- son and Kina, as opening at the hinge-line or posterior margin of the platform. No similar structure, or any tendency to its formation, has been observed in any other species; on the contrary, the strong cardinal buttress usually occupies this median position. Several specimens of the pedicle-valye of this species, after having the matrix carefully removed by means of caustic potash, give no evidence whatever of this opening, the shell being perfectly continuous from the platform to the deltidium, and we are led to suggest that the external opening of this cavity, so out of harmony with the typical characters of the genus, may be due to fortuitous causes. The cardinal buttress, however, is replaced by a remarkably broad and deep excavation. BRACHIOPODA. 35 out the Trimerellas, the scars are much less sharply defined than in the other genera of the family. Thus, there may be no sufficient reason to doubt that when this apophysis is developed, it is analogous to the cardinal process in the articulates ; and we have confirmatory evidence of this function of the process in its great development in Lakumina. The platforms in the Trimerellas have usually about the same relative degree of development, being generally slightly larger in the brachial than in the pedicle-valve, and vaulted for almost if not quite their entire length, except in the species T. Billingsi, Dall, where they are solid for about two-thirds their length. This species again indicates the tendency toward Monomeretta in the gradual obliteration of these platform-vaults. The usual faintness of all the muscular impressions must be due, in an important degree, to the condition of preservation of the fossils. The shells were among the most ponderous of all brachiopods, and the muscles to wield them must have been of great size and have produced strong scars. The American specimens of TRIMERELLA are almost invariably internal casts in dolomitic limestones, and the removal of the shell- substance left great space for the operation of crystallizing forces which would go far toward the obliteration of these impressions. An interesting feature is the not infrequent irregular development in the vaults of the platform, one being sometimes shorter or broader than the other. A tendency to lateral asymmetry in the growth of the umbonal portions of the shell is sometimes seen, resulting in a deflection of the beak and platform to one side. (See Plate IV a, fig, 3.) In some species, noticeably in T. acuminata, Billings, the platform of the pedicle-valve bears a deep median furrow, beginning at the base of the cardinal buttress and narrowing anteriorly. This feature is developed, to a greater or less degree, in most of the species, and may represent the position of the ovar- ies (post-median scar, Davipson and Kine). TRIMERELLA is represented in American faunas by five species: T. grandis and T. acuminata, Billings; T. Billingsi, Dall; T. Dalli, Davidson and King; T. Ohioensis, Meek. All-these are known to occur in the Guelph limestone of the 36 PALAHONTOLOGY OF NEW YORK. Province of Ontario; T. Ohioensis, T. grandis and T. acuminata are known in the Niagara dolomites of Ohio, and T. acuminata from Port Byron, Ilinois, but, strangely enough, we have no knowledge of the occurrence of any species of the genus in association with the great numbers of Monomeretta and Drinosowus in the rocks of the same age in Wisconsin; T. acuminata has been found by LinpstR6M in association with T. Lindstremi, on the islands of Gotland and Faré ; T. Wisbyensis, Davidson and King, is a little known species from the former island. The age of the Swedish specimens is that of the Aymestry and Wenlock limestone of Great Britain. Genus DINOBOLUS, Hat. 1871. PLATE IVB, FIGS. 13-24. 1850. Lingula, Rovautr. Bull. Soc. Géol. de France, 2nd ser., vol. vii, p. 128. 1853. Obolus, Davipson. Introduction to British Fossil Brachiopoda, p. 58. 1858. Obvolus, Birunes. Rept. Geological Survey Canada, p. 189. 1859. Obolus, SAurer. Murchison’s Siluria, Second Ed., p. 543. 1860. Obolus, Linpsrrém. Ofvers. af Kong. Vetenskaps-Akad. Forhandl., p. 375 1862. (Conradia), Hatt, MS. See Davidson, Quart. Journ. Geol. Soc., vol. xxx, p. 159, foot note. 1874. 1863. Lingula, Sauter. Quarterly Journal Geological Society, vol. xx, p. 294, pl. xvii, figs. 2, 3, 6. 1866. Lingula, Davipson. British Silurian Brachiopoda, p. 41, pl. i, figs. 21-26. 1866. Obolus, Davipsoy. British Silurian Brachiopoda, p. 59. 1868. Obolus, Hatt. ‘Twentieth Rept. N. Y. State Cab. Nat. Hist., p. 368, and 1870, idem., Revised Edition, p. 375. 1868. Obolus [ Trimerella?], Meex and Worrnen. Geol. Survey Illinois, vol. iii, p. 351, pl. v, fig. 7. 1869. Lingula, Davipson. Quarterly Journal Geological Society, vol. xxvi, pl. iv, fig. 3, 1871. Dinobolus, Hart. Notes on some New or Imperfectly known Forms among the Brachiopoda, p. 4, March; in advance of Twenty-third Rept. N. Y. State Cab. Nat. Hist. 1873. 1871. Obolellina (partim), Bruunes. Canadian Naturalist, p. 222. December. 1871. Trimerella (partim), Dat. American Journal of Couchology, vol. vii, pt. 2, p. 83. 1872. Obolellina (partim), Brouincs. Canad. Nat., p. 330, Dec.: Amer. Journ. Sci., vol. iii, p. 359. 1872. (Conradia), Haut. American Journal of Science, Third Ser., vol. iv, p. 107; and, 1873, Twenty- third Rept. N. Y. State Cab. Nat. Hist., p. 250. 1872. Dinobolus, Davipson and Kina. Rept. Brighton Meeting Brit. Association. 1872. Dinobolus, Davipson and Kine. Geol. Magazine, vol. ix; and Ann. and Mag. Nat. Hist., vol. x. 1874. Dinobolus, Davipson and Kine. Quart. Journ. Geological Society, vol. xxx, p. 159. + 1875. Dinobolus, Hart and Wuitrietp. Geol. Surv. Ohio; Paleont., vol. ii, p. 130, pl. vii, figs. 3, 4. 1875. Dinobolus, Nicuotson. Paleontology Province of Ontario, p. 18, fig. 6a; p. 68, fig. 38. 1879. Tyrematis, BaRRANDE. Systéme Silur. Bohéme, pl. 94, fig. vi; pl. 95, fig. x. 1880. . Dinobolus, Davipson. Geological Magazine, new ser., vol. vii, p. 340, pl. x, figs. 1-6. 1881. Dinobolus, Davinson. Br. a of the Budleigh-Salterton Pebble-bed, p. 363, pl. xl, figs. 22, 23 1882. Dinobolus, WHITFIELD. Gages of Wisconsin, vol. iv, p. 347, pl. xxvii, figs. $-10. BRACHIOPODA. 37 Draenosts. Shell sub-circular ; valves convex, thick. Pedicle-valve with an acute and slender beak; cardinal area triangular, more or less elevated, but never so high as in TriereLia or Monommretta. Cardinal margins sometimes of considerable width. Umbo generally solid, but often slightly excavated on either side of a simple or double vertical wall, or buttress. Crescent distinct, its apex making a retral angle; narrow over the crown, widening into the great terminal scars. Platform low, broadly V-shaped on its anterior margin, which usually les at about the middle of the valve; generally, with very short, flattened, abruptly conical vaults, but occasionally these vaults are of the same relative length as in Trimeretia, though much shallower. Central and lateral muscular scars on the platform usually distinct, the former lying in a depressed median groove, the latter occupying the greater portion of the surface. Subcardinal and anterior scars rarely discernible. Anterior median septum scarcely developed. Pallial sinuses faint. Brachial valve with the beak submarginal, inconspicuous and usually not discernible; hinge-area very narrow. Crescent very strong, especially over the crown, where it makes.a sharp posterior angle beneath the beak, sloping thence very gently, being almost transverse for about the width of the platform, then bending quite abruptly and being slightly interrupted at the position of the terminal scars, which are more approximate than in the opposite valve. In the type-species, the crown of the crescent, as usually developed, is a sharply incised, narrow furrow, bounded within by a broad ele- vation sloping to the position of the subcardinal scar, but not infrequently it is a ridge, bounded in front and behind by a deep furrow. This difference in appearance is due to the varying development of the anterior furrow, which is sometimes quite suppressed. Platform narrower and more sharply V-shaped than in the opposite valve; vaults usually very short and abruptly conical. Lateral and central scars on the platform conspicuous, the latter lying in a deep median furrow, at the front end of which are sometimes seen the faint anterior scars. In the line of this furrow, directly in front of the apex of the crescent, lies the deep impression of the subcardinal muscle, which makes a prominent feature on the cast, suggestive of the filling of the umbonal cavity, which it 38 PALHHONTOLOGY OF NEW YORK. may be to some extent, although the apex of the beak is actually quite remote from it. From this point to the center of the crescent extends a short furrow, on either side of which lies the impression of an accessory scar, probably cor- related to the umbo-lateral scars of Raryosontus and TrmereLia. Pallial sinuses more or less distinct. Median septum low, but stronger than in the opposite valve. Type, Dinobolus Conradi, Hall. Oxservations. Such considerable variations in certain features occur within the limitations of a single species of this genus, that we are disposed to regard the recognition of the eight or nine species, which have been described, of somewhat questionable authenticity. We have before us a large number of finely preserved specimens of the type-species, D. Conradi, from Le Claire, lowa; Cedarburg, Wisconsin; Hawthorne and Port Byron, Illinois; all of which indicate that variations are to be expected (1) in the development of the delti- dium, which though usually quite low, may attain a very considerable eleva- tion; (2) in the size of the platform-vaults, which in both valves, are usually no more than a broad, general excavation of the anterior walls of the platform, narrowing abruptly into minute conical cavities, though in the pedicle-valve they occasionally are long and tubular, and, in both valves, there is some- times evidence of a tendency to form two or even three chambers in each vault; this may be regarded as an abnormality, but it occurs in at least six instances in the examples at hand; (3) in the position of the platform, its apex usually lying at about the center of the valve, but sometimes situated more posteriorly. Upon comparing the features of the interior of D. Conradi with the best known of the other species, D. Davidsoni, Salter, we do not observe features which lead to a satisfactory specific distinction. From the figures given by Davipson and Kine,* it appears that this species is also susceptible of varia- _tion, for example, in the development of the median scar in the pedicle-valve, which may be either a ridge or a furrow. In the description and figures of * Loe. cit., pl. xviii, figs. 6-11. BRACHIOPODA. 39 Dinobolus Schmidti, Davidson and King, from Esthonia, Russia, as given by these authors, it is impossible to cite specific differences from D. Conradi; D. Cana- densis, and D. magnificus, Billings, are known only from their exterior; D. Woodwardi, Salter, is imperfectly understood, while D. transversus, Salter, D. parvus, Whitfield, and D. Bohemicus, Barrande, appear to be well defined species. The close relationship of Divopotus to Monomeretza is apparent both in the slight development of the umbonal cavities in the pedicle-valve, and in the gen- eral aspect of the interior of the brachial valve, the shape of its platform and development of its muscular scars. The differences, however, are of perma- nent value. No true platform-vaults are formed in either valve of Monomsr- ELLA, merely a broad, general excavation of the anterior walls of the platform ; moreover, the crescent in this genus never attains the strong and peculiar development seen in Dryoso.us, but is more of the nature of that in TRimprELLa. The approach to TrimereLa indicated by the long vaults occasionally seen in Drnozotus, has been referred to, but in no instance among the Trimerellas or Monomerellas has there been observed any tendency to a duplication of these vaults, as in Dinosontus. In some respects, therefore, Dinosouus stands as the connecting link of these two genera; or, as it was the first of the genera to appear in paleozoic faunas, it may be naturally considered the more comprehensive type of Trimeretia, Monomerutna and Ratosotus, from which these latter may have derived many features by easy stages of evolu- - tion. Dryoso.us makes its first appearance in the Lower Silurian,* D. Brimontz, Rouault,+ being from the Budleigh-Salterton pebbles, and various localities in Brittany, of the age of the lower Llandeilo, or the Grés Armoricain; D. magnificus, Billings, and D. Canadensis, Billings, from the Black River limestone * Mr. Davipson described a species, Dinobolus ? Hicksi, from the Upper Avenig of St. Dayid’s (Quart. Journ. Geol. Soc., vol. xxxi, p. 188, pl. x, fig. 6. 1875; and British Silurian Brach. Suppl., p. 212, pl. xvi, fig. 19. 1883), but the characters of the single specimen are so obscure as to render this réference exceed- ingly questionable. f + Davipson. Brachiopoda of the Budleigh-Salterton Pebble-bed, p. 365, figs. 1, 2 (p. 366), pl. xl, figs. 22, 23. 1881. 40) PALHIONTOLOGY OF NEW YORK. (Trenton); D. parvus, Whitfield, from the Galena limestone (Trenton) at Whitewater, Wisconsin; D. Schmidti, Davidson and King, is stated to be from the Lyckholmer Schichten of Esthonia, Russia, considered to be nearly the equivalent of the Caradoc and Trenton; the greatest individual development of the genus, however, is in the Niagara fauna and its equivalents, D. Conradi being the American representative of D. Davidsoni, Salter, a Wenlock species occurring near Dudley and elsewhere in England, county Kerry, Ireland, and on the Island of Gotland; D. transversus and D. Woodwardi, Salter, are from the same horizon, and the Trematis Bohemica, Barrande (— Dinobolus), is from an equivalent fauna (Etage H-e,). Gexyus MONOMERELLA, Buuoes. 1871. PLATE IV c, FIGS. !-18; AND PLATE IVD, FIGS. 1-15. 1871. Monomerella, Brnuinas. Canadian Naturalist, vol. vi, p. 220. 1872. Monomerella, Davipson and Kine. Ann. and Mag. Nat. Hist.; Geol. Mag. ; Report Brighton Meeting of British Association. 1874. Monomerella, Davipsoy and Kine. Quarterly Journal Geological Society, vol. xxx, p. 155. 1875. Monomerella, Nicuorson. Rept. Palzxontology of the Province of Ontario, p. 68. 1875. Monomerella, Hatt and Wuirrretp. Geol. Sury. Ohio; Palzont., vol. ii, p. 131, pl. vii, figs. 1, 2. 1884. Monomerella, WuirEaves. Paleozoic Fossils, vol. iii, pl. 1, pp. 5, 6. Draenosis. Shell usually thick, but in some cases quite thin; outline vary- ing from elongate-ovate to subcircular. Surfaces of contact of the valves some- times conspicuously broad. Pedicle-valve with a more or less elevated umbo, which may vary in height in a given species, in the type-species being high, as in TRIMERELLA; umbonal cavity divided into two chambers by a longitudinal septum. Cardinal area large; deltidial ridges and deltidial callosities not always distinctly developed; cardi- nal slope usually well defined, merging anteriorly into the cardinal buttress, or umbonal septum; in some species this slope, or subtriangular area, is longi- tudinally divided by a furrow. The crescent is sharply impressed over the cardinal slope; terminal scars broad and distinct. Platform more or less developed ; divided by the cardinal buttress, which extends nearly or quite its entire length. Muscular impression on the platform very large, covering the BRACHIOPODA. 4] entire surface, but rarely resolvable into separate scars. Anterior septum indistinct, usually imperceptible. ~-Pallial sinuses sometimes clearly defined. Brachial valve with the umbo seldom conspicuously developed, the umbonal cavity being usually simple and deep, but sometimes filled by a deposition of shelly matter. Crescent sharply impressed over the narrow cardinal slope, and produced into broad, indistinct, composite terminal scars. Platform usually well developed and broadly excavate on its anterior walls, but sometimes scarcely discernible. Anterior and lateral scars sharply defined, giving a tri- partite appearance to the platform. Anterior septum more strongly developed than in the opposite valve. Type, Monomerella prisca, Billings. Osservations. The very rich material that has been before us in the study of this genus, has added a number of interesting and previously unknown forms, and the variations from the type-species shown by these, has made it neces- sary to modify in some respects the diagnosis of MonomergELta, as given by Daviwson and Kine. At the date of their work but four species were known, and the four additional species, which, for convenience in discussing the genus, are described in the supplement to this volume, present some important deviations from the type-form, and necessarily broaden the scope of the genus. Mr. Brrtines’ species, Monomerella prisca and M. orbicularis, from the Guelph limestone at Hespeler, Canada, were first illustrated by the English writers, who also added two new species, M. Walmstedti, from the Aymestry limestone of Gotland, and M. Lindstremz, from the Wenlock near Wisby The former of these Gotland species is very closely allied to M. prisca. Indeed, we are com- - pelled to include under this latter name, American forms which vary so con- siderably in the elevation of the cardinal area, size of the umbonal chambers of the pedicle-valve, and the depth of the umbonal cavity in the brachial valve, that with this broader conception of the specific characters of M. prisca, it would be easy to consider M. Walmstedti as conspecific. The specimens of M. prisca, from the dolomites of the Niagara group, at the Rising Sun quarries, Wood county, Ohio; Hawthorne, Port Byron and Cicero, Illinois; and near 42 PALAZONTOLOGY OF NEW YORK. Cedarburg and Grafton, Wisconsin, show not only the high area and deep chambers of the Canadian types, but deviations therefrom, which, if found in specimens unassociated with the intermediate forms, might be regarded as of distinct specific value. We have, on a preceding page, called attention to essentially similar variations in the species Dinobolus Conradi. The cardinal area of the pedicle-valve in M. prisca is always erect, and its subdivisions are sharply defined; a broad, usually convex though depressed deltidium is bounded by elevated deltidial ridges merging into the areal borders, and has the deltidial callosities or articulating (?) apophyses more strongly developed than elsewhere noticed among the Trimerellids. On the other hand, in M. Ortoni, the cardinal area, equally broad and high, is gently incurved, as in Rutopo.vs, and is transversely striated, but has only very faint evidence of longitudinal subdivision In M. Greenti and M. ovata, this area is low, smooth, and not subdivided, but is continued about the margins into a broad surface of contact with the other valve. In the brachial valve of M. prisca and M. Kingi the cardinal area is slightly if at all developed, the beak being marginal; while, in M. Greenii, it is somewhat elevated, and, in M. Egani, very prominently developed. ‘The development of the umbonal chambers depends essentially on the height of the umbo, and the degree of its thickening; in M. prisca always extending above the hinge-line, in M. ovata and M. Kingi they reach to the hinge, and, in M. Greenii, rarely appear to extend so far. The umbonal cavity of the brachial valve is subject to even greater variation, but this is more largely an individual than a specific divergence. In the thin-shelled species, M. Greenii, this cavity is invariably deep, but in M. prisca it appears to be frequently thickened by internal deposition. This feature is also seen in M. Kingi, and in the single valve representing the species, M. Egani, we have an example of this umbonal thickening carried to an extreme. The platform, never so strongly developed as in TrimereE.ia, nor furnished with vaults, is usually a conspicuous feature, but in M. Greenii it is almost obsolete, its position being evident only from the slightly thickened muscular scars. BRACHIOPODA. 43 Generally these muscular scars are sharply defined. Those on the platform of the pedicle-valve indicate very large organs, but in M. prisca we have been unable to resolve them as Davipson and Kine have done. In M. Greenii, the lateral scars are clearly outlined and limited to a comparatively small sur- face. Their small size may be largely due to the fact that the valves of this species were comparatively light ; their position, close together on either side of the median septum, is very suggestive of the muscular arrangement in Scuizocranta In M. Ortoni there appears a prominent anterior scar with fainter laterals, bordered in front by narrow converging furrows. On the brachial platform, the subdivision of the muscular impression is always strong, producing a trilobate appearance; sometimes the shell is so preserved as to show the long progressive track of the laterals and the centrals, at others, the older portions of the scars are covered by an organic deposit limiting the impressions to the area last covered by the muscular bands. In one species, IM. Ortoni, the impressions of the pallial vessels, both primary and secondary, are very distinct, and this is the only instance in which the ramifications from the main vascular trunks have been observed in this group. MonoMeERrELLA Is readily distinguished from the allied genera by its two umbonal chambers and low, unvaulted platforms. In the brachial valves of this genus, and of Dinopo.us and Rurosotus, the similarity in internal features is very close, and care is required in the generic determination. In Drnozotus the plat- forms are always vaulted, to some degree, by conical cavities, and not merely broadly excavated on the anterior walls; the umbonal cavity is a small, acute depression, never filled by testaceous deposit ; the crescent is always broad, with abrupt lateral angles. RuxrnopoLus possesses a very short platform, strongly elevated at its anterior margin, and sloping abruptly backward, but there is no evidence of its general suppression as sometimes occurs in MoNoMERELLA. Species of this genus, like those of Trmerenna, are very limited in faunal range. The Canadian examples are all from the Guelph limestones of the Province of Ontario; those from the States of Ohio, Illinois and Wisconsin are from dolomites usually referred to the age of the Niagara of New York ; 44 PALHVONTOLOGY OF NEW YORK. but probably serving as a faunal equivalent of the Niagara and Guelph forma- tions. No species are’known in Great Britain, those from the Island of Got- land, and from Livonia, Russia, are from faunas corresponding to that of the Niagara and Wenlock. Genus RHINOBOLUS, Hat. 1871. PLATE IVB, FIGS, 7-12. (?] 1862. Obolus, Binruines. Paleozoic Fossils, vol. i, p. 168, fig. 151. 1871. Tvrimerella, Datu. American Journal of Conchology, vol. vii, p. 83. 1871. Rhynobolus, Haut. Advance sheets (March) Twenty-third Rept. N. Y. State Cab. Nat. Hist., p. 247, pl. xii, fig. 10. 1873. [2] 1871. Obolellina, Bruuincs. Canadian Naturalist, vol. vi, New Series, p. 220 (December). 1872. Dinobolus, Davipson and Kinc. Report Brighton Meeting of British Association. 1874. Trimerella (?), Davipson and Kine. Quart. Journ. Geological Society, vol. xxx, p. 151, pl. xviii, fig. 13; pl. xix, figs. 4, 4a. [2] 1884. Rhynobolus, WurrEAves. Paleozoic Fossils, vol. iii, pt. 1, p. 7, pl. ii, fig. la; pl. viii, figs. 3, 3a. Diagnosis. General form of the shell as in Trimeretta. Pedicle-valve, in the typical species, with an elevated, solid beak, having a broad and high deltidium, divided into a relatively narrow central area (which may be concaye or convex), and broad deltidial ridges. Crescent and terminal scars as in Trmeretta. Umbo-lateral scars sharply defined. Platform very low and incompletely developed, consisting of a broadly V-shaped elevation, with a raised anterior margin, and surface sloping abruptly backward to, or even below the general curvature of the internal surface. Trimerella. > Lingulella ~ /— Monomerella —— Rhinobolus. vas Lingula —— Lingulops Lingulasma~ It is probable that the progenitor of OsoLus will be found in OBoLELLA, or some of the closely allied genera, and our present knowledge of LinGuLELLa is such that, as elsewhere observed, it must be placed in juxtaposition to OBOLELLA, while evincing a deviation toward Lryeuta. The two are, in all probability, but a few removes from their common ancestor, which may be looked for in the earliest primordial faunas, unless its existence was limited to obliterated BRACHIOPODA. 53 faunas of still earlier date. Ruinopotus has the aspect of a degenerate Trim- erellid, marked by the general obsolescence of the characteristic features of the group. In Laxumia, we have evidence that the platforms attained a con- siderable development before the introduction of Silurian faunas. Features, which in American faunas appear to have developed slowly, and whose different stages can be satisfactorily traced, seem to have been specialized with great rapidity in this obscure fossil. It is not necessary to assume that this fossil from a distant fauna, now regarded as of primordial age,* will materially modify the conclusions expressed in the foregoing diagram, derived from the study of American faunas. Having indicated that the inception of the platform was probably due to aug- mented muscular energy and concomitant increased secretion of muscular fulcra, we may revert to the consideration of the function of this organ in its highest development, and to the inquiry, whether this attainment may have been acquired alone by the constant action of the forces named, or has been aided to this result by the accessory action of other organs. Whether or not the platform be hollow as in Trimeretia and Laxkamina, and sometimes in Drnopzotus, or solid, as usually in Dinosouus, and always in the other genera, there is invariably a manifest tendency toward its excavation. The anterior walls are always concave; in Monomeretta the concavity of the plate is deep, the anterior moiety being turned with a steep slope toward the cavity of the shell; furthermore, the shell itself is much depressed beneath this projecting wall and on either side of the anterior median septum into which the platform is continued. The same features are seen in the brachial valve throughout these genera.+ Even in Rutnopotvs, all that is left of the platform is turned upward and inward at this sharp angle. In the pedicle-valve, how- ever, this inclination of the platform, the excavation of its anterior walls and * See pagé 29. + Mr. Unricu describes a peculiar structure in the platform of Lineurasma. He says: ‘The cast of the interior which furnished the gutta-percha squeezes represented by figs. 5 and 5a” (see Pl. II, fig. 19), ‘‘ oriy- inally preserved much of the shell and all of that pertaining to the platform. This was carefully removed, and during the process it was noticed that the platform consisted of numerous cup-shaped laminz placed within one another, and so that an open space was left between each and the preceding and succeeding ones” (American Geologist, vol. iii, No. 6, p. 386. 1889). 54 PALHHONTOLOGY OF NEW YORK. depression of the surrounding surface of the shell is never so marked; the platform itself is of less size throughout, and we have noticed that in the course ‘of its development it does not make its appearance so early as in the brachial valve. The lead held by the brachial valve in this respect, as shown in Lineu- Lops and Ex.Kanta, is maintained throughout the entire history of the organ. The cause of this is not far to seek. In Lrneuna, the anterior portion of the visceral region lying directly in front of, and behind the insertion of the anterior muscular bands, is occupied by the liver. In L. anatina, rather the greater portion of this body lies behind these muscular scars, but in LinauLors there is a general posterior concentration of all these muscular bands. In such a case the retro- gression of the muscles could not force the liver g AHHH into a more contracted space or otherwise SN \\\ Min displace it than to change its relative position TM) and leave the large muscular bands behind it. \\ SOMME Lip MU) QQ Lis) 6 ° . ‘ : be ZG! SS This organ (the liver) is large, and les mostly i At oa << on the dorsal aspect of the animal, the surface rama oe S there covered by it, in L. anatina, being con- 2 i i Fic. 17. Lingula anatina. siderably more extensive than on the opposite Av oral aspect, showing the arrangement of the : A nh - . viscera on the inner surface of the brachial side. It is also distinctly bilobed by the longi- vaive (after Kune). The h, cenwal scars. a, liver. J, anterior lateral b, genitalia. scars. e, alimentary canal. tudinal septum on the brachial valve. pressure of this organ against the anterior edges of the area of muscular implantation must have been of significance in induc- ing the formation of the anterior elevated margins of the muscular scars, and in this pressure, continued as a constant force in both valves, though less in- tensely in one than in the other, may, perhaps, be found an efficient cause for the abrupt termination of the muscular area, its elevation, its concave anterior walls, and, eventually, its complete excavation, as well as the depression of the adjoining surfaces of the shell. In discussing the genus Dinopo.vs, attention has been directed to the tendency BRACHIOPODA. 5 occasionally manifested in both valves of the species to form two or three vaults on either side of the platform. In animals of the size indicated by these shells the lobation of the liver may have been so strongly developed as to pro- duce this peculiar effect in the excavation of these cavities. Admitting the sequestration of the liver in Trimeretia, a freer play would undoubtedly be left to the muscles and greater opportunities of development, and this fact will have had both a direct and inverse bearing on the size attained by both the platform and the shell itself. In regard to the great umbonal chambers of the pedicle-valve in Monomer- ELLA, and their lesser development in Dryopo.us and TRimeRreLLA, they have pos- sibly served a similar function to the platform-vaults, by removing the delicate genital organs from dangers which might arise from the action of the muscles. In Lingula anatina, these organs lie normally in the median and posterior portion of the visceral region, pressing backward against the post-parietal wall, and are placed mostly on the ventral side of the body. In offering an interpretation of the arched posterior scar in Lineutors, Davipson and Kine suggested that the middle sinus of the arch might have been produced by the umbonal muscle pressing against the parietal wall, and the lateral sinuses have been due to the pressure of the ovarian lobes against this muscular wall. Were this the case in the genus where all these features are in an initial stage of development, it would readily be conceived how by this constant pressure the genital organs may have developed the umbonal cavities for their own protection. Genus LINGULELLA, Satrer. 1866. PLATE II, FIGS. 1-18. 1852. Lingula, McCoy. Annals and Magazine of Natural History, Second Series, vol. viii, p. 405. 1852. Lingula, McCoy. British Paleozoic Fossils, p. 252, pl. 1 1. 1859. Lingula, Sarrer. In Murchison’s Siluria, Fourth Edition, p. 43. 1866. Lingulella, SsutER. Mem. Geological Survey of Great Britain, vol. iii, p. 333. 1866. Lingulella, Daviwson. British Silurian Brachiopoda, p. 55. 1867. Linguwlella, Saurer. Quarterly Journal Geological Society, p. 340. 1868. Lingulella, Davipson. Geological Magazine, p. 303. 1871. Lingulella, Davipson. British Silurian Brachiopoda, p. 336. 56 PALHONTOLOGY OF NEW YORK. (2) 1842. Lingula, Emmons. Geology N. Y.; Rept. Second District, p. 267 (not fig. 68). (1) 1847. Lingula, (Conrap) Hatt. Paleontology N. Y., vol. i, p. 3, pl. i, fig. 2. 1847. Orbicula, Hatt. Paleontology N. Y., vol. i, p. 290, pl. Ixxix, figs. 9a, b, ¢. () 1860. Lingula, Hatt. Thirteenth Rept. N.Y. State Cab. Nat. Hist., p. 76, fig. 1. 1861. ZLingula, Hatt. Annual Report Geological Survey of Wisconsin, p. 24. 1862. Lingula, Bruunes. Paleozoic Fossils, vol. i, p. 71, fig. 64. 1863. Lingula, Hau. Sixteenth Rept. N. Y. State Cab. Nat. Hist., pp. 126, 127, pl. vi, figs. 4-8. 1867. Lingula, Haru. Transactions Albany Institute, vol. v, p. 103. 1871. Obolella, Birtincs. Canadian Naturalist and Geologist, vol. vi, p. 218. 1871. Obolella, Forp. American Journal of Science, vol. ii, p. 33. 1871, Lingulella, Merx. Proceedings Academy of Natural Sciences, Phila., vol. xxiii, p. 185. 1873. Lingulella, Hatt. Twenty-third Rept. N. Y. State Cab. Nat. Hist., p. 245, pl. xiii, fig. 5. 1874. Lingulella?, Binunes. Paleozoic Fossils, vol. ii, p. 57, fig. 36. (2?) 1875. Lingulella (Dignomia ?), Haut and Wuirrrerp. King’s Report U. S. Expl. Fortieth Parallel, p. 206, pl. i, figs. 3, 4. 1875. ZLingulepis, Harz and Wurrrretp. King’s Rept. U. S. Expl. Fortieth Parallel, p. 232, pl. i, fig. 8. 1878. Lingulella, Forp. American Journal of Science, vol. xv, p. 127. ; (2) 1878. Lingula, Wuivraves. American Journal of Science, yol. xvi, p. 226. 1882. Lingulella, Wurrrietp. Geological Survey of Wisconsin, vol. iv, p- 334, pl. xxvii, figs. 6, 7. 1884. Lingula?, (Marruew) Watcorr. Bulletin No. 10, U. 8S. Geological Survey, p. 15, pl. v, fig. 8. 1885. Lingulella, Marruew. Illustr. Fauna St. John Group, No. 3, pp. 33, 34, pl. v, figs. 7, 8. 1886. Lingulella, Waucorr. Bull. No. 30, U. S. Geol. Sury., pp. 95, 97, pl. vii, figs. 1, 2; pl. viii, fig. 4. 1887. Lingulella, Waucorr. American Journal of Science, yol. xxxiy, p. 188, pl. i, fig. 15. 1889. Lingulella, Waucorr. Proceedings United States National Museum, 1888, p. 441. Diagnosis. “Shell nearly equivalve, broad-oblong, the ventral valve pointed, with a distinct pedicle-groove. Muscular scars strong, nearly as in Osotus, but the pair of anterior retractors are more linear and the slidimg muscles small, and not quite external as in Opotus” (Sauter. Memoirs Geological Survey of Great Britain, vol. iii, p. 333. 1866). Type, Lingulella Davisit, McCoy. «The name LINGULELLA was first introduced about 1861, with the late Dr. S. P. Woopwarn’s full consent; and the name appears at p. 9 of Sir RoprrtcKk Murcuison’s Address to the Geological Section of the British Association, Manchester, 1861; but it is only in Mr. Sanrer’s Appendix to the ‘ Memoir on the Geology of North Wales, that the genus is for the first time described” (Davinson, British Silurian Brachiopoda, p, 55. 1866). Osservations. Under the discussion of the genus Liyeuna, attention has been directed to the peculiarities of the cardinal area in the type-species, L. anatina, and its close similarity with that of Lingulella Davisi. The necessity of great caution in assigning generic character from these features alone has also been expressed. In Linauna the deltidium bears a broad pedicle-groove, BRACHIOPODA. 57 while in Lryeutetta the opening for the passage of the pedicle is a sharply de- fined slit, not merely making a depression upon the sur- face of the cardinal area, but apparently penetrating it from apex to cardinal line Varying conditions of pres- ervation will often make the determination of this feature difficult; but, aside from the character of the cardinal area, there is little known of the type-species of Linau- “Yaya navi nter Davpson LELLA Which can be satisfactorily regarded as of generic value.* Mr. Satter suggested a similarity in the muscular scars of L. Davis?, and those of Oso.us and Osotetta; Davipson, however, was unable to find examples of the species showing these impressions satisfactorily,y but called attention to the coarse puncte over the visceral surface of one individual. The generic term LinGuLELta has been used with considerable freedom by both American and English writers, but while there must remain a degree of uncertainty in regard to the correct generic character of many species now in- cluded under this name, there are a few primordial forms which are pretty well understood, both externally and internally; but whatever conclusions in regard to the generic features of LincuLELLA are derived from the study of these, must be dependent upon the results of future investigations upon the type- species, 1. Davisi. Mr. C. D. Watcort has givent figures of Lingulella Ella, Hall and Whitfield, which show not only the characteristic cardinal area and pedicle-slit, but give very distinctly the character of the muscular impressions on both valves. There will also be found on Plate I, figs. 1-4, of this volume, illustrations of the interior of both valves of Lingulella celata, Hall (Orpicuna, Hall, 1847, * Dr. Wine was strongly disinclined to admit the term LinGutetta. In his work upon the ** Characters of Lingula anatina,” he says: ‘*The deltidium is a variable structure in Palliobranchs generally ; and its modifications are far from being understood. As regards the deltidium in the genus under consideration {Linevra], one circumstance is remarkable: it has been in a great measure overlooked ; at least I can find little, or rather no notice of it in the writings of previous observers. It is this oversight which led the late J. W. Sarrer to institute bis genus LinguLe.ia, which he typified with the Cambrian Lingula Davisi, under the belief that its ‘pedicle-grooyve’ and ‘ hinge-area’ do not characterize any species of the old Bruguiérian genus” (Ann. and Mag. Nat. Hist., Fourth Ser., vol. xii, p. 14. 1873). + Silurian Brach., p. 55. { United States Geological Survey, Bull. 30, pl. vii, fig. 2; and pl. viii, figs. 4a, b, c. 1886. 58 PALHONTOLOGY OF NEW YORK. OpoLeLta and Lineutenya, Ford), which show a close agreement inthe internal characters of these species. In the pedicle-valve the lateral scars make the long sweeping curves so characteristic of OpoLELLA, while the centrals, more or less coalesced, produce a broad, somewhat tripartite scar. In the brachial valve of L. Lila, appear to be two diverging lateral scars, ex- tending about one-half the length of the shell, and incurving at their anterior Lingulella Ela, Wail and Whitfield. Alter WALCOTT. ends toward the more conspicuous and Fic. 19. Dorsal aspect, showing pedicle-area. FIG. 20. Inter- nal cast of pedicle yalye. Fic. 21. Internal cast of brachial yalve. apparently compound central scar. Essentially the same characters are seen in the brachial valve of L. celata, accompanied by posterior lateral scars, which occupy a position homologous with the terminal scars in the Trimerellids. An additional character is given to the muscular scars of the brachial valve in Mr. Watcorr’s figures of his species, Lingulella Granvillensis,* in which there appears, near the center of the shell, a faintly defined, bilobed scar, continued anteriorly into an oval impression. These represent the “anterior adductor muscular scars, and also what may have been the adjustor muscular scars > or the anterior laterals and the centrals of Lineuta. This feature constitutes a conspicuous difference from the obolelloid character of these impressions in the brachial valves of the other species cited, and it will be important to verify the character. The pedicle-valve of this species shows the straight (?) diverging ridges similar to those in L. Dawsoni+ Figures have been given by Mr. Davipson, showing the muscular scars in the species L. ferruginea, Salter,{ and L. lepis, Salter.|| In both these species the elongate, more or less curved laterals are apparent, enclosing a compound central scar not essentially differing from that in L. Ella, though more sharply outlined. * American Journal of Science, vol. xxxiv, p. 188, pl. i, fig. 15 a. 1887. + Waxcort, loc. cit. B { By the favor of Mr. G. F. Marruew we are enabled to give an original figure of the interior of this species taken from the specimen represented in his ‘* Ilustrations of the Fauna of the Saint John Group,” No. 3, pl. v, fig. 9@ (Trans. Roy. Soc. Canada, Sec. iv. 1885). We have not observed the sharply defined muscular impressions represented by Mr. Marruew. § Mon. Brit. Sil. Brach., pl. xlix, figs. 33a, 85a. 1871; and Geol. Mag., vol. v, No. 7, pl. xy, fig. 3a. 1868. | Mon. Brit. Sil. Brach., pl. xlix, fig. 31a. 1871; and Geol. Mag., vol. y, No.7, pl. xv, figs. land lla. 1868. BRACHIOPODA. 59 As long as our knowledge of the interior characters of LinguLe.ia is limited to the few species cited, the genus may tentatively include such forms as have shown the high cardinal area and the distinct pedicle-slit. It is, however, in a broad sense, characteristic of the first or primordial faunas, and it has not been satisfactorily demonstrated that any species outside these faunas can be safely referred to the genus. Lingulella lowensis, (Qwen) Whitfield, is a proper Lineuta; Lingulella Cincinnatiensis, Hall and Whitfield, probably belongs to the same genus. The Lingula paliformis, Hall, of the Hamilton shales, has a distinct cardinal area, an apparently sharply defined pedicle-slit, with faint linear muscu- lar or septal scars. It does not appear to be a true Lingua, and, with our present knowledge, it is impossible to discover wherein it differs from LIn@uLELta. This genus has proved much more abundant in American than in European faunas, but of the twenty-five or more species which have appeared in American literature under this generic designation, fully two-fifths should be eliminated ; while, on the other hand, some species passing current under the genus LineuLa may eventually prove to be LinGuLeLta. Genus LINGULEPIS, Hatt. 1863. PLATE I, FIGS. 35, 36. 1847. Lingula, (ConraD) Hatz. Paleontology N. Y., vol. i, p. 3, pl. i, fig. 3. 1851. Lingula, Hatt. Foster and Whitney’s Rept. Geol. Lake Superior, p. 204, pl. xxiii, fig. 2. 1852. Lingula, OWEN. Rept. Geol. Sury. Wisconsin, Iowa and Minnesota, p. 583, pl. id, figs. 4, 6, S. 1863. Lingulepis, Hatt. Sixteenth Rept. N. Y. State Cab. Nat. Hist., p. 129, pl. vi, figs. 12-16 1875. Lingulepis, Wuirrirtp. Ludlow’s Rept. Reconnais. Black Hills, p. 103. (2) 1876. Lingulepis, N. H. Wiycuett. Fourth Ann. Rept. Geological Survey of Minnesota, p. 41, fig. 6.3 1877. Lingulepis, Hatt and Wuirrmip. King’s Rept. U. 8. Expl. Fortieth Parallel, pp. 206, 207, 232. 1877. Lingulepis, Wuirrietv. Prelim. Rept. Paleontology Black Hills, pp. 8,.9, pl. ii, figs. 5-9. 1882. Lingulepis, Wuirrietp. Geology of Wisconsin, vol. iy, p. 169, pl. i, figs. 1, 2. 1884. Lingwlepis, Wuirrrerp. Bull. American Museum of Natural History, vol. i, No. 5, p. 141. “ SHexts linguloid, inequivalve, equilateral, oval-ovate or spatulate; muscular impression in one valve, flabelliform; in the other, tripartite, the lateral divi- sions larger. Shell corneous, phosphatic.”* Type, Lingula pinniformis, Owen. Since the original description of this genus, little has been added to our knowledge of its characters. The number of species that can be assigned to * Hatt. Sixteenth Report New York State Cabinet of Natural History, p. 126. 1863. 60 PALHVONTOLOGY OF NEW YORK. the group without hesitation is quite small, and if the generic features of the type-species L. pinniformis, are strictly adhered to, it may be necessary to restrict the specific representation to very narrow limits. The original species is the most thoroughly understood in both exterior and interior details. The ex- ternal character of the shell itself, when both valves are present, allows of a ready distinction from all known forms of the genus Lincuta. The pedicle- valve bears a long, attenuate rostrum, which extends far beyond the apex of the opposite valve. This appears to have been open on the lower side for its entire length, for the passage of the pedicle, though we have no conclusive evi- dence that it may not have been partially covered by a thin deltidium of similar character to that in Lingula anatina. The brachial or dorsal valve is broadly ovate in outline, having an obscure beak and a general form which would be in precise agreement with that of the opposite valve, were the rostrum of the latter truncated at its base. The separated valves of L. pinniformis occur in great quantities in the Potsdam sandstone at the Falls of St. Croix, Min- nesota and Wisconsin, crowded together to the exclusion of any other fossil, and there can be no doubt that the valves described in the Sixteenth Report of the State Cabinet of Natural History, as dorsal and ventral, are such, although no specimen has been seen in which the valves are in their natural juxtaposition. The muscular impressions of the pedicle-valve may be determined with tolerable accuracy. A single large scar, occupying the entire umbonal region, is produced anteriorly into two narrow lateral branches, extending for about one-half the length of the shell. Between them and con- tinuous with their posterior portion, lies a central scar, not extending so far forward, but together with the lateral branches giving the é o . . n: Fies 22.23. Lingulepis pinniformis. entire muscularimpression a strongly tripartite Z,1ateralsears. ¢, central. __s, septum. character. The homology of these scars with those of Lryeuta is not readily apparent, although there is a degree of similarity which is quite strongly shown in the outline of the central scars. Probably the entire muscular impression would, under perfect preservation, be resolvable into more detailed scars, but BRACHIOPODA. 61 there is no doubt that the conspicuous laterals correspond more or less exactly with the /aterals, and the central scar with the cenérals in Linauta. LIinauLepis also bears a broad and low median ridge, elevated along its margins and de- pressed in the middle, similar to, but fainter than that in L. anatina. Although the similarity to Lryeuta in these respects is evident, a much closer homology is found in the muscular scars of this valve of Lincutepis and that of LineuLutta. This is seen in the crescentic laterals and the prominent central in LinguLeLia. In Osotetta, the posterior coalescence of these scars is even more prominently developed than in Liyeutetta. In the muscular scars of the brachial valve, the divergence from Lrnauna is still more marked. These impressions make a conspicuous flabelliform scar, extending medially about one-half the length of the shell. The central portion of this scar is accompanied on either side by broader, partially resolvable lateral sears, all the subdivisions of the impression coalescing in the umbonal region. Here the crescentic laterals of LincuLenia and OBoLELLA are quite absent, but the posterior coalescence of all the scars into one broad and ill defined impression, is a feature noticeable in all of these genera. Thus the genus Lincutepts affords an important connecting link between Lineuna and Lineuce tra in the direct line of relationship to OsoteLia and its allied genera. The shell-structure of LinguLepis is, presumably, closely similar to that of Lineuta, and, as usually in that genus, its surface-ornamentation is uniformly of concentric lines. L. pinniformis also shows a few faint radiating lines, which are more strongly developed on the internal surface over the anterior portion and on the interstitial lamellee of the shell. The genus, as far as known, is represented only in American primordial faunas ; L. pinniformis, of the Potsdam sandstone of Minnesota and Wisconsin, finds a closely allied species in L. antiqua, Hall, of the same formation in New York. Two species, L. cuneolus and L. perattenuata, have been described from the Black Hills, by R. F. Wurrrisip,* and in the same year Haut and Warr- FIELD} referred three species to this genus, L. Ella, L. Mera and L.? minuta. The first of these has since proved a LineuLetia, and it is probable that the * Preliminary Rept. Geology of the Black Hills. 1877. + Kiya’s Report United States Geological Exploration Fortieth Parallel. 62 PALHHONTOLOGY OF NEW YORK. other two are to be referred to the same genus. Mr. Wuattrrenp* has also de- scribed a species, L. minima, from the Potsdam sandstone of New York. Adding to these the L. Morsensis (Morsii) of N. H. Wincuett,y we find that the genus is thus far represented by six species, but of all these the interior characters of the typical species only are satisfactorily known. Genus BARROISELLA, Gen. nov. PLATE II, FIGS. 14-16. 1868. Lingula, Meex and Wortuen. Geological Suryey of Ilinois, vol. iii, p. 437, pl. xiii, fig. 1. enf. 1866. Lingula, Davipson. British Silurian Brachiopoda, p. 42. enf. 1870. Lingula, Wixcurti. Proceedings American Philosophical Society, vol. xiii, p. 248. cnf. 1873. Genus?, Kinc. Annals and Magazine Natural History, Fourth Series, vol. xii, p. 13. enf. 1881. Lingula?, Davipson. Brachiopoda Budleigh-Salterton Pebble-bed, p. 361. enf. 1887. Lingula (Glottidia), Frecu. Zeitschr. der deutsch geolog. Gesellsch., vol. xxxix, p. 392. Diagnosis. Shell externally as in Lineura. The pedicle-valve béars a high cardinal area, which does not appear to be a shelf, as in Lineuta and Lineutetta, but a thickened triangular plate, which is divided by a broad pedicle-groove. On the basal margin of the cardinal area, at the angles made by the lateral margins of the pedicle-groove, is a pair of bosses or condyles, which have undoubtedly served either as muscular fulcra, or, to some extent, as points of articulation with the opposite valve. The interior of the pedicle-valve shows a subquadrate depressed area lying directly beneath and almost in continuation of the pedicle-groove ; this may represent the umbonal muscular scar. From its ante-lateral angles diverge two sharply defined, linear depressions, which extend about one-fourth the length of the shell and end abruptly. From outside and behind the extremities of these depressions, begins a pair of long, curved furrows, which are composed of two shorter curves, the posterior rounding over the extremities of the linear de- pressions referred to above, the anterior and longer curves gradually approxi- mating and nearly meeting at a point about one-third the shell’s length from the anterior margin. These furrows are accompanied by low ridges along their inner margin. A low median ridge, with elevated edges, begins at the posterior umbonal impression, and continues to the center of the valve, widening near * Bulletin American Museum of Natural History, vol. i, No. 5, p. 141, pl. xiv, figs. 1, 2. 1884. + Geology of Fillmore County, Minnesota. 1876. BRACHIOPODA. 63 its anterior extremity. Just behind its termination is a pair of small, usually indistinct muscular impressions, probably the scars of the central muscles. In the brachial valve the beak is scarcely prominent, and the muscular mark- ings are essentially as in the opposite valve, but more sharply developed. Beneath the beak is a faint umbonal scar, the diverging lines from which are discernible. The long, compound lateral curves have a considerably greater degree of curvature than in the pedicle-valve, their posterior portion enclosing a thickened area, which is continued into a peculiar low and thickened median septum, bifurcating in the middle of the valve, the angle being occupied by an intercalated ridge, which extends for twice the length of the branches of the septum. This peculiar bifurcation may be due to the impression of the anterior muscular scars at this point. The central scars are situated further back- ward at the junction of the median septum with the posterior thickened area. Type, Lingula subspatulata, Meek and Worthen. Oxzservations. There can be no sufficient reason to doubt the generic differ- ence of shells possessing the above characters from described linguloids. The condyles on the cardinal margin are themselves a dis- tinctive feature. We have already directed attention to Dr. Kine’s observations upon this peculiarity in Lingula? Lesueuri, Rouault,* a species which shows evidences upon the cast, of two deep pits close to the beak. In his opinion this character alone is sufficient to exclude the species from the genus Lineuta. Mr. Davinson subsequently comparedy+ this species (L. Le- _sueurt) with the recent Glottidia Palmeri, Dall, finding in %6.%. Linguia? Lesucuri, Rouault, : Internal cast of pedicle-valve. both the development of a median septum in the pedicle- NMP IDISARSONG valve and two lateral septa in the brachial valve. Just such septal features are found in the pedicle-valve of B.subspatulata if we choose to consider the diverg- ing umbonal furrows as homologous with the lateral septa in Giorripia; but they are not found in the brachial valve. The other internal markings of this species are widely different from those of Lincuta. The central muscular scars are *Vide supra. Annals and Magazine Natural History, July, 1873, p. 13. + Brachiopoda Budleigh-Salterton Pebble-bed, p. 362. 64 PALZZVONTOLOGY OF NEW YORK. placed very far back, especially in the brachial valve, where the thickened area against which they abut, and the semicircular lateral impressions bounding the area, suggest the compound central muscular thickening and the curved lateral scars seen in some species of Osotetta. The long curved anterior furrows in both valves at once suggest homology with the vascular trunks or pallial sinuses in Lincuta. No specimens of these shells, however distinctly the in- terior markings may have been preserved, give any indication of branches from either side of these furrows, and it may be well to bear in mind in determining the relations of the genus, their similarity to the long laterals in OBoLELLA. On the basis of interior characters, Lingula subspatulata is the only species known that can be safely referred to this genus. This form was described by Meek and Worruen in 1868,* from the black shales (Genesee horizon) underly- ing the Goniatite limestone (Kinderhook) near Rockford, Indiana, and Union county, Illinois. Professor A. Wincuetty has suggested the specific identity of a form found in the black shales at Vanceburg, Kentucky, and elsewhere on both sides of the Ohio river, included within the Waverly series, but this is evidently a higher horizon than the Indiana and Illinois occurrence, and we surmise that the Waverly form mentioned by Professor Wincuett will prove to be the L. Mele, Hall. The same author also suggests the identity of L. subspatulata, Meek and Worthen, with his L. membranacea, from the Burlington sandstones. The only figure we have of this latter form is one given by Megxt in 1875, in which there are indications of the high cardinal area and apophyses in the former species, though the quadrate outline of L. membranacea gives it a specific impression distinct from that of L. subspatulata. The Lingula paliformis, Hall, of the Hamilton shales of New York, may also prove to belong to BarrotseLia, though the character of the cardinal area and the internal markings as far as now known, do not serve to distinguish it from Lineutetta. With Barroisetta may be compared the Bohemian species Lingula Davidsoni, Barrande,§ and L. insons, Barrande,|| from the Etage D. * Geological Survey of Illinois, vol. iii, p. 437, pl. xiii, fig. 1. + Proceedings American Philosophical Society, vol. xii, p. 248. t Paleontology Ohio, vol. ii, pl. xiv, fig. 4. § Systéme Silurien, vol. v, pl. 104, fig. viii. | Systéme Silurien, vol. v, pl. 105, fig. x. BRACHIOPODA. 65 Genus TOMASINA,* gen. Nov. Under the name, Lingula Criei, Mr. Davison described, in 1881,7 a linguloid fossil from the Armorican grit of the Département de la Sarthe, having a cardinal area of such peculiar structure as to render its separation from the genus LineuLa necessary. “The pedicle-valve is very slightly convex, its posterior margin being notched. This notch is divided into two parts Lingula Criei. Atter Dayrpson. ¢ 0 6 Figs. 25, 26. Internal cast and interior of posterior portion of by a small triangular elevation, pedicle-valve. leaving on each side a well de- Fic. 27. Internal cast of pedicle-valve. Natural size. fined depression or little cavity. Aside from this slight elevation, the valve presents a gentle longitudinal convexity, which extends a little in front of the center of the valve, the lateral portions of the shell remaining almost flat. The opposite valve appears to have been somewhat more convex than that we have described. “This notch in the area for the passage of the pedicle is very remarkable, and I have never before observed it in any of the numerous species of the genus which I have studied. In the interior of this same valve, beneath the pedicle- aperture, there are two small processes with a depression between them, and the central muscular impressions are well defined, but I have been unable to find any other impressions upon the internal casts which M. Guttiier has sent me.” The internal processes upon the cardinal margin are so large that they may have served purposes of articulation to some extent. In this respect the fossil shows structure similar to that seen in its associate in the same fauna, Lingula ? Lesueuri, Rouault. * Out of regard for the memory of Mr. Davipson, to whom we are indebted for our knowledge of this fossil, the above name is proposed. t Bulletin de la Société Géologique de France, p. 372. 1881; Note sur les Lingules du grés armoricain de la Sarthe, par M. A. Gurturer, avec descriptions et figures des espéces, par M. Tx. Davipson, pl. vii. 66 PALAZONTOLOGY OF NEW YORK. Genus OBOLELLA, Bitutnes. 1861. PLATE II, FIGS. 31-44. 1847. Orbicula?, Hatt. Paleontology N. Y., vol. i, p. 290, pl. Ixxix, figs. 8a, b. 1847. Avicula?, Hatt. Paleontology N. Y., vol. i, p. 292, pl. Ixxx, figs. 3a, b. 1852. Obolus, Owen. Geological Survey of Wisconsin, Iowa and Minnesota, pp. 501, 631, pl. 1B. 1860. Lingula?, Haun. Annual Report Geological Survey of Wisconsin. 1861. Obolella, Bruuinas. Geology of Vermont, vol. ii, p. 946. 1862. Obolella, Binuinas. Geology of Canada; Paleozoic Fossils, vol. i, p. 7. 1862. Obolella, Meek and Haypen. Proceedings Acad. Nat. Sci. Phila., vol. xiii, p. 435. 1863. Obolella?, Haut. Sixteenth Rept. N. Y. State Cab. Nat. Hist., p. 133, pl. vi, figs. 17-21. 1865. Obolella, Meek and Hayprey. Paleontology Upper Missouri, pp. 3, 4. 1866. Obolella, Davinson. British Silurian Brachiopoda, p. 60. 1871. Dicellomus, Haru. Advance sheets Twenty-third Rept. N. Y. State Cab. Nat. Hist. 1871. Obolella, Brruincs. Canadian Naturalist and Geologist. 1872. Obolella, Binuincs. American Journal of Science, vol. iii, p. 355. 1873. Obolella, Ford. American Journal of Science, vol. vy, p. 213. 1876. Obolella, Bituncs. American Journal of Science, vol. xi, p. 176. 1877. Obolella?, Hatt and Wuitrretp. King’s Rept. Exploration Fortieth Parallel, p. 205. 880. Obolella, Wuirrintp. Paleontology of the Black Hills, pp. 339-341. 1881. Obolella, Forp. American Journal of Science, vol. xxi, p. 131. 1884. Obolella?, WaAtcorr. Paleontology Eureka District, p. 67. 1886. Qbolella, Waucorr. Bulletin No. 30, U.S Geological Survey, pp. 109-119. 1889. Obolella, Watcorr. Proc. U. 8. National Museum, vol. xii, p. 36. Diaenosis.* Shell inarticulated, ovate or suborbicular, lenticular, smooth, concentrically or radiately striated, sometimes reticulated by both radiate and concentric strie. Ventral valve with solid beak and a small, more or less distinctly grooved area. In the interior of the ventral valve there are two elongated, sublinear or petaloid muscular impressions, which extend forward from near the cardinal scars, sometimes to points in front of the mid-length of the shell. These are either straight or curved, parallel with each other or diverging toward the front. Between these, at about the middle of the shell, is a pair of small impressions, and close to the hinge-line a third pair, likewise small, and often indistinct. There is also, at least in some species, a small pit near the hinge-line, in which the groove of the area seems to terminate. The dorsal valve has a small, nearly flat hinge-facet; the minute beak is slightly incurved over the edge of the area. Beneath the beak there is a small subangular ridge, on each side of which there is a cardinal (?) scar. The elon- * Derived from Mr. E. Briuryas’ diagnosis in 1872 (loc. cit.) and the emended description of the type- species, O. chromatica, by the same author in 1876 (loc. cit.). BRACHIOPODA. 67 gate scars, which seem to correspond to the laterals of the ventral valve, are here altogether in the upper half of the shell, diverging widely in their exten- sion forward, and are generally very slightly impressed. In the cavity of the valve there is a low, rounded median ridge, which extends from a point near the hinge-line forward to a little below the mid-length of the valve. About the middle of the shell there are two small scars. These are usually striated longitudinally, the median ridge passing between them. The area is coarsely striated. Type, Obolella chromatica, Billings. Observations. Since the date of Mr. Briures’ studies of OsoteLia,* much valuable information in regard to the character of the interiors of these shells, especially of the brachial valve, has been contributed by Mr. 8S. W. Forp, in various papers in the American Journal of Science, and by Mr. C. D. Watcort, in Bulletin No. 30 of the United States Geological Survey. Mr. Biutines assumed three species as types of his genus: (1) O. chromatica ; (2) the Avicula? desquamata, Hall (— O. crassa, Hall) from the limestones near Troy, N. Y.; (3) “A small species from the Potsdam sandstone of the St. Croix River,’ which had been described by Professor Hatt as Lingula? polita,s and was subse- quentlyt referred with some degree of doubt to the genus Opo.Ena. The original figures of O. chromatica, the first- mentioned type-species, gave but a very imperfect representation of the character of the interior of the pedicle-valve, and showed only the two elongate GREER OT oe lateral muscular scars.{ Subsequently the figures pyg.os raterior of petiele-valve, here copied, were published by Mr. Britines in the "Meter ot bmohiat valve. American Journal of Science,|| giving the interiors of both valves, as far as then known to him; previously, however, in the same journal, he * Paleozoic Fossils, vol. i, 1861; Canadian Naturalist, 1872; Amer. Jour. Science, 1872 ; Jdem, 1876, etc. + 1860. Report Geological Survey Wisconsin. { 1863. Sixteenth Report N. Y. State Cab. Nat. Hist. § Paleozoic Fossils, vol. i, p. 7. | Vol. xi, 1876, p..176. q Vol. iii, 1872. 68 PALAEONTOLOGY OF NEW YORK. had given excellent figures, showing very completely the characters of the pedicle-valves of O. desquamata (= O. crassa, Hall), and O. gemma, Billings. But in 1863,* the interiors of both valves of Obolella ? polita, Hall, had been illustrated, and the figure given of the pedicle-valve (there termed “ dorsal ?”’) represents the impressions almost precisely as we now know them to be in the corresponding valve of O. chromatica, O. crassa, and others; while those of the opposite valve, usually less distinctly retained than in the pedicle-valve, show the long, curved laterals and-the central scar. (See further under discussion of Dicettomus.) In 1881, Mr. Forpy; demonstrated the interior characters of the brachial valve of O. crassa, subsequently amplifying his observations some- what in a figure published by Mr. Waxcorr in Bulletin No. 30, 1886. In this work, Mr. Watcorr also gives a figure of the interior of the same valve of O. chromatica, demonstrating the complete harmony of its scars, both in arrangement and development, with those of O. crassa. The same author gives, in addition, illustrations of the interiors of O. gemma, and O. Circe, Billings. The genus OBoLsLLA possesses, as far as known, a larger specific representation than any other group of primordial brachiopods, but all species that have been referred to the group are not congeneric. The true OBoLELa, as far as it is accurately known, is not only confined to primordial faunas, but is believed to be largely American in its representation. The forms referred by English writers to the genus fail to show the characteristic generic features. Some of them have already been assigned to other genera, e. g., O. sagittalis, Salter, to Linnarssonta, Walcott, to which genus probably belong O. Belti, Davidson, and O. maculata, Hicks; O. Sabrine, Callaway, will undoubtedly prove a repre- sentative of a distinct genus, its relations to Acrorrera having been pointed out by Mr. Watcorv. Certain of M. Barranpg’s species show internal features indicating their close alliance to Opo.etna, e. g., Lingula Feistmanteli,t Obolus? complecus,, Obolus * Hay. Sixteenth Rept. N. Y. State Cab. Nat. Hist. (loc. cit.). + American Journal of Science, vol. xxi, p. 131. { Syst. Sil. Bohéme, vol. v, pl. 106, fig. iv. § Syst. Sil. Bohéme, pl. 95, fig. iii; pl. 111, fig. vi; pl. 152, fig. ii, 4. BRACHIOPODA. 69 advena.* These are all from the Etage D, and should they prove referable to OpoLELia, will constitute the latest recorded appearance of the genus. The American species which can safely be classed as OBoLELLA are the fol- lowing: O. chromatica, Billings, O. crassa, Hall, O. Circe Billings, O. gemma, Billings, and probably O. polita,; Hall.t Of other species referred to the genus by American. writers, it may be remarked : O.? ambigua, Walcott,{ will probably prove referable to the genus ExKanta, as suggested by the author of the genus, Mr. Forp.|| O. celata, Hall, == Lingulella celata (Orbicula calata, Hall"). O. cingulata, Billings, = Kutorgine cingulata. O. desiderata, Billings,** is the type-species of ELKanta. O. ? discoidea, Hall and Whitfield ;+; generic character in doubt, as the interiors are not known. O.? Ida, Billings,tt is imperfectly known. O.? misera, Billings,§§ is referred to the genus Linnarssonia, by G. F. MartHew.|||| O. nana, Meek and Hayden.11 Mr. Watcorr is disposed to consider this * Syst: Sil. Bohéme, pl. 95, fig. iv. t+ The Lingula prima (Conran’s MS. description, first published by Haut, Pal. N. Y., vol.i, p.3. 1847), from the Potsdam quartzite at Ausable Chasm, N. Y., has been referred by Mr. Wurrrietp (Bull. American Museum Nat. Hist., vol. i, No. 5, p. 142. 1884) to the genus OBoLetra, and is also identified by him with the species O.? polita, Hall, from the yellow pulverulent sandstones at Trempaleau, Wisconsin, so that, should this identification hold good, the latter name will become a synonym of the former. ‘The identitica- tion is, however, made solely on the basis of external similarities, and must be regarded as subject to such modifications as the interior characters, when known, may require. These have not been satisfactorily demonstrated in the New York species, but there are specimens before us which indicate that its muscular impressions are more nearly those of LinautEeria than of OpotEtLA. The Obolella nitida of Mr. S. W. Forp, also considered by Mr. WHITFIELD a synonym of the same species (op. cit.), appears, from an examination of the type-specimens, to be a totally distinct fossil. { Under the name Obolella Atlantica, Mr. Waucorr has mentioned, without giving a detailed description, an additional species from the Olenellus zone, Conception Bay, Newfoundland (Proceedings U.S. National Mus., vol. xii, p. 36. 1889). § Paleontology Eureka District, p. 67, pl. i, figs. 2a-c. 1884. | American Journal, vol. xxxi, p. 467. 1886. q Paleontology N. Y., vol. i, p. 290, pl. Ixxix, fig. 9. ** Paleozoic Fossils, vol. i, p. 69. 1862. tt Geographical and Geological Exploration Fortieth Parallel, p. 205, pl. i, figs. 1,2. 1877. t{ Paleeozoic Fossils, vol. i, p. 71, figs. 68a, b. 1862. §§ Paleozoic Fossils, vol. ii, p. 69. 1874. ||| Illustrations Fauna St. John Group, No. iii, p. 35. 1885. 4 Paleontology Upper Missouri, p. 4, pl. i, figs. 3 a-d. 70 PALAONTOLOGY OF NEW YORK. species as identical with O. polita, Hall,* but specimens of both species, from the original localities of each, show differences in the much less convexity of O. nana, its more triangular outline, and its usually smaller size. Should these differences prove constant, the species may be regarded as well defined. O. nitida, Ford.+ Mr. Forp’s specimens show a very tenuous phosphatic shell which has not retained any trace of the internal characters. O. pretiosa, Billings.t Interiors of the type unknown. Mr. Watcort suggests their relationship to Acroruetn ;{ but specimens which have been placed in our hands by Sir Witttam Dawson, from the Quebec group at Little Metis, and which show no external differences from O. pretiosa as described by Brt.tyes, have all the internal characters of the genus Linnarssonta. O. transversa, Hartt, — Linnarssonra, Walcott. Our discussion of the generic characters of OpoLeLLta must, therefore, be limited to observations made upon the authentic species cited. Primarily, a distinct cardinal area is developed in each valve. On the pedicle-valve this feature is much the more conspicuous, and is crossed by a pedicle-groove, which is not a slit cut through the area, but only a depression on its surface. The brachial valve on the other hand shows only a broad sinuate depression as seen in the figure of O. gemma given on Plate II (fig. 43 [34 in error]); in O. crassa this valve has a somewhat triangular area with a very slight ridge occupying a position correlative to the pedicle-groove of the other valve. Mr. Forp’s figure, given in Bulletin No. 30, United States Geological Survey,|| makes this feature much stronger than it actually appears in the specimen from which the drawing was made. Though the same feature is shown in Mr. Wa.cort’s figure of the brachial valve of O. chromatica,’ it remains to be determined whether or not it is a constant character in these species. * Bulletin No. 30, U. 8. Geological Survey, p. 111. } American Journal of Science, 1878, vol. v, p. 213. { Palseozoic Fossils, vol. i, p. 68. 1862. § Bulletin No. 30, U. 8. Geological Survey, p. 111. | Pl. x, fig. 1 a. 4] Bulletin No. 30, U. 8. Geological Survey, pl. xi, fig. 10. BRACHIOPODA. el The latter author also describes and figures* a brachial valve of O. gemma from Bic Harbor, below Quebec, in which the cardinal area is quite narrow and bears a deep pedicle- groove. It is possible that this feature may be subject to so great variation within the limits of the same species as in- dicated by Mr. Watcort’s figure and our own; but this point Fie. 36. Brachial valve of O. gemma. After WALCOTT. requires verification. In the pedicle-valve the groove on the area is followed by a deep pedicle muscular impression, which is flanked on either side by narrow, elongate cardi- nals. The lateral scars begin near the pedicle-pit or scar and curve gently outward, and again inward near their distal extremities, extending two-thirds, sometimes three-fourths the length of the shell. They are not always a simple groove, but in O. crassa each margin of the impression is more deeply sunken than the rest, thus leaving a low ridge between them. In the post-median region, the central scars are usually ill-defined but evidently compound, and in O. crassa are seen to consist of three subcircular scars, two outer and one inner; these are bordered on the anterior side by a series of thread-like ridges and furrows. In O. gemma the entire central scar is more deeply impressed, and partakes of the tripartite character, the median portion being the most prominently developed. In the brachial valve, the laterals take their origin in the median region of the shell, adjacent to, or in the central impressions, and curve outward. An excellently preserved interior of this valve of O. crassa shows a subrhom- boidal central scar with straight sides and with the apex pointed posteriorly ; the margins are more depressed than the center, but the impression is not divided by a ridge into two scars, as represented in Mr. Forp’s figure.+ The laterals branching from this scar are very broad and slightly curved. In other species the central impression is usually indefinite in its details, as in the pedi- cle-valve, but shows a subdivision into outside and median scars. The cardinals in O. crassa are well defined and, at their anterior extremities, * Bulletin No. 30, U. 8. Geological Survey, p. 117, pl. x, fig. 2d. + Bulletin No. 30, U. S. Geological Survey, pl. x, fig. 1 d. Cae PALHONTOLOGY OF NEW YORK. merge into a pair of elongate submarginal scars, which may be termed the ez- ternals. They appear to represent the terminal crescent scars in the Trimerel- loids, but cannot, with propriety, be regarded as correlates of the great laterals of the opposite valve (see Forp, Watcort, op. cit.). The term Dicetnomus was proposed in March, 1871, in a paper published in advance of the Twenty-third Annual Report on the Condition of the State Cabinet of Natural History, for the species which had been previously described as Obolella? polita,* the Lingula? polita, Hall, 1860,; and the Obolus Apollinus, Owen, 1852.t This species was also the third type under Biiuines’ diagnosis of OsorettA. Dicrt.omus was also made to include, as a second type, the Orbi- cula ? crassa, Hall, 1847, but this latter species proves to be congeneric with Obolella chromatica. The interior characters of the former species are still some- what imperfectly known, the original illustrations of them which are repro- duced upon Plate II (figs. 40, 41), being somewhat constructive, but the pedicle- valve, while showing an unusually strong cardinal area, has the pedicle-groove, the cardinal, lateral and central muscular scars, quite as in typical Obolellas; in the brachial valve the apparent correspondence of the scars with those of Obolella chromatica and O. crassa is less marked. Upon this plate are given ad- ditional figures of the interior of this species, the pedicle-valve (fig. 38) showing two very strong centrals, bounded, on the posterior margin, by a thickened, triangular area, extensions from which pass between and around the outer sides of the scars. The outer posterior margins of this area bear the impressions of the cardinal or external muscles, while below the position of the pedicle-groove (the cardinal area is not retained on this specimen) lies a pedicle-scar. The whole appearance of this ‘interior is strongly suggestive of that in Oso.us, but may not prove inconsistent with the character of Oponetna. In the brachial valve, the impressions are more distinctly obolelloid, the long, curved laterals taking their origin at the compound central scar. The development of the in- terior details of the shells of this species is a matter of much difficulty, as the * Sixteenth Rept. N. Y. State Cab, Nat. Hist., p. 133. 1863. + Annual Report Geological Survey Wisconsin, p. 24. { Report Geological Survey Wisconsin, Iowa and Minnesota. BRACHIOPODA. 73 substance of the shell is friable and chalky, and the sandstone so loose-grained that internal impressions are not distinctly retained. Should future study of the species prove it generically distinct from O. chromatica, it will be necessary to accord recognition to the term DiceLtLomus, which, however, may be held in abeyance until that time. There is a noticeable similarity in the interior of the pedicle-valve of O. polita as shown in fig. 38, to the illustration given by Vo- BorTH of the interior of the corresponding valve in the species Schmidtia celata,* in which all the details represented are the two strong cen- tral sears abutting against a thickened posterior area. The correspondence in internal markings does not appear to ex- tend to the brachial valves. (See discussion of the genus, Scumiptra.) Attention may also be directed to the Obolus ? FIG. 31. Obolus? complexus. complerus of Barranve,y from the Ktage D, apparently a After Barranpe. genuine OBoLecta, in a later fauna than has been elsewhere observed. Genus LEPTOBOLUS, Hatt. 1871. PLATE III, FIGS. 1-10. 1871. Leptoholus, Hatt. Descriptions New Species Fossils, p. 3; Advance sheets Twenty-fourth Rept. N. Y. State Mus. Nat. Hist. 1872. Leptobolus, Hatu. ‘I'wenty-fourth Rept. N. Y. State Mus. Nat. Hist., p. 226, pl. vii, figs. 17-20. 1875. Leptobolus, Haut and Wurrrietp. Palacntology of Ohio, vol. ii, p. 69, pl. i, figs. 10, 11. Diacnosis “ Shell semiphosphatic, fragile, minute, more or less elliptical, ovate or subcircular, with moderately (or sometimes more extremely) convex valves, which are concentrically marked on the exterior surface. Ventral valve with a distinct pedicle-groove; interior with an elevated subquadrate muscular area. Dorsal valve a little thickened on the cardinal margin, with slightly elevated, trifid muscular impressions,” Haut (loc. cit.). Type, Leptobolus lepis, Hall, Hudson group, loc. cit., p. 226, pl. vii, figs. Is ADs L. occidens, Hall, Hudson group, loc. cit., p. 227, pl. vii, fig. 18. * Verhandl. der russ.-kais. Mineral. Gesellsch. zu St. Petersb., 2te Ser., Bd. iv, taf. xvii, fig. 1. 1868. t Systéme Silurien Bohéme, vol. y, pl. 152, fig. ii, 4; also, pl. 95, fig. iii; pl. 111, fig. vi; pl. 113, fig. v. TA PALHIONTOLOGY OF NEW YORK. Opservations. There is a noticeable variation in the internal characters of the species referred to this genus, but it does not appear to be of an essential nature, or of a greater degree than might be expected in different species ; indeed this variation is strikingly apparent in different individuals of the same species. Of the interiors of the three known species of Leproso.us, that of L. occidens is not yet satisfactorily known, but those of both the other species are of not uncommon occurrence. L. lepis is found in the Utica slate of New York, at Holland Patent, and elsewhere, having been washed by thousands into the rill- marks or depressions in the sediment, but upon cleaving the rock the shells are exposed with their interiors usually attached to the matrix, making it necessary to remove the scale-like shell in order to ascertain the internal characters. In the gray, muddy shale of the lower part of the Hudson group of Ohio (Utica horizon), the same species has accumulated in great numbers, and by breaking the rock the interiors are usually exposed; the specimens are, therefore, in a much more favorable condition for study. Leptobolus insignis, readily distinguished from L. lepis by the radiating striz on its internal surface, is found in much the same condition of preservation, but in the more compact layers of the Cincinnati or Hudson group. It will be understood that shells washed about as these have been, may often have lost the clear definition of their delicate interior impressions, but examples are not infrequent which retain with great sharpness all the internal details. The interior of the pedicle-valve shows a notably large cardinal area, which is sharply grooved. Beneath this area, in the bottom of the valve, is a-broad depression extending nearly across the shell, and divided by a low median ridge, which bifurcates at its extremity, leaving between its branches a small central muscular impression. This latter feature is more clearly developed in L. lepis than in L. insignis, but in the latter species the entire depression is much more clearly defined, its ante-lateral margins being produced slightly for- ward. This impression is bounded on its sides by acrescentic muscular fulerum, which extends, parallel with the margins, to the anterior portion of the shell. At a point back of their centers, each gives out a transverse branch extending in- BRACHIOPODA. (i) ward and backward. ‘These callosities are strongly suggestive of the appear- ance produced by the combined lateral and central scars in Obolella chromatica and O. crassa, and it is probable that they represent the same features, in which case the posterior depressed area is to be regarded as the progressive track of the centrals, its anterior margin advancing with age. The position of the valve lying between the anterior horns of the lateral semilunes is also deeply depressed, but its surface shows no markings. The specimens of L. lepis from the Cincinnati rocks appear not to have retained these lateral callosities, but they are faintly developed in the New York exam- ples of the same species. In the brachial valve, the cardinal area has about the same degree of devel- opment as in OpoLeLa, and is also distinctly grooved. The muscular scars in this valve are poorly defined, but their limits are probably indicated in part by the septa, which in L. lepis are three in number; one in the axial line larger than the rest, and one on either side. All these ridges appear to be bifurcated at their anterior extremities, in the axial ridge the faint duplication beginning at about the center. In the Utica slate specimens of L. lepis the lateral ridges, in the only satisfactory example observed, appear to be curved inward toward their extremities, as they also are in L. insignis where they attain a very con- spicuous development, uniting with each other in front and being separated from the margin of the shell only by a low furrow. These ridges may be re- garded as the curved fulera of the lateral muscles. The features seen in Leproso.us indicate its close alliance to Osotetia, but are at the same time so diverse from those of Obolella chromatica that the forms can not be regarded as congeneric. Genus ELK ANIA, Forp. 1886. PLATE III, FIGS, 15-19. 1862 Obolella, Biuuines. Paleozoic Fossils, vol. i, p. 69, fig. 62a, b. 1884. Obolella?, Watcorr. Paleontology Eureka District, p. 67, pl. i, fig. 2. 1886. Billingsia, Forp. American Journal of Science, vol. xxxi, p. 466. 1886. Elkania, Forp. American Journal of Science, vol. xxxii, p. 325. This genus has been established by Mr. 8. W. Forp upon the late Mr. Brnurnas’ species, Obolella desiderata, from the Graptolite shales at Pointe Lévis. We have 76 PALHIONTOLOGY OF NEW YORK. had before us for the study of this form, Mr. Briuives’ original specimens, which give very clearly the interior characters of both valves. These were lucidly described by the author, although he was not disposed to regard them as gener- ically distinct from Obolella chromatica. ‘This description, given upon page 70 of the work cited, is in the following terms: “From some nearly perfect casts of the interior, the following characters can be made out. In one of the valves (supposed to be the ventral) a strong rounded groove commences just beneath the beak, and runs along the median line to about the center of the shell. On each side of the principal groove is a large ovate muscular impression, extending from near the mid-length of the shell a little more than half-way to the beak. These impressions are bounded and distinctly defined at their lower extremities by the two small, diverging grooves above mentioned. Their outer and upper margins are distinctly de- fined. In the rostral part of the shell there are two small grooves which take their origin close to the beak, one on each side, and run toward the front, diverging to the outside of the upper part of the two large muscular impres- sions. The characters of the interior of the dorsal valve are somewhat similar to those of the ventral valve, but the median groove is shorter, and there is a thickening of the shell just below the beak, which presents the appearance of a false area inside the cavity of the umbo. It is probable that the two small grooves above mentioned are connected with the small muscular impressions, which, in O. chromatica, are distinctly seen outside of the two larger. The condition of our specimens, however, is such that this point must remain open for further investigation.” In subsequently proposing to desiguate this shell by the term Butuinesta (a name afterwards changed to ELxanra as the former proved to have been already in use), Mr. Forp gave a much enlarged and somewhat schematic figure of the pedicle-valve (which we are disposed to believe emphasizes rather too strongly the internal characters), and accompanies it with the following diagnosis of the generic characters (Joc cit., page 467): ‘Shell thin, calcareous, inarticulate, longitudinally ovate or subcircular, con- vex. Ventral valve with a solid beak and a minute area, which, in the typical species, 1s grooved for the passage of the pedicle as in Osotetta. Muscular impressions in the ventral valve, six; one pair situated close to the cardinal BRACHIOPODA. C0 edge, one on either side of the median line; a second, smaller pair, placed directly below the former; and outside of the latter a third pair of large elon- gate or subreniform impressions, converging forward. Beneath the rostrum there is a prominent spoon-shaped pit or chamber separating the above men- tioned impressions, with which the groove of the area is confluent. In the dorsal valve there are also three pairs of impressions disposed in nearly the same manner with those of the ventral valve. The dorsal valve is not known to possess an area. The surface is concentrically striated.” From the specimens before us, the shell-substance of Elkania desiderata appears to be largely corneous and distinctly laminated. Several examples in which the external layer of the shell has been exfoliated are covered with conspicuous papillee which may indicate a punctate structure in the inner layers, a feature not hitherto noticed in OpoLeLia or its immediate allies. We have not been able to discover the minute cardinal area mentioned by Forp, although this feature should have been retained on the specimens examined, if it was distinctly developed. On the contrary, there appears to be, just within the marginal apex of what is above considered as the ventral valve, a broad, subtriangular depression, into which the central ‘“ spoon-shaped” cavity merges. This central cavity, in five examples of the interior of this valve, has a more or less distinct development, its definition being sometimes obscured by the flattening of the shell. When best preserved, it shows two narrow furrows diverging from its anterior extremity, which continue a short distance and be- come abruptly extinct. These two furrows separate the anterior extremities of the broad lateral muscular scars, which are quite indistinctly limited, while the smaller impressions, termed by Forp the “centrals”, are faint, but dis- tinctly seen in favorable light. The two small grooves in the rostral portion of the shell, diverging from the beak, were regarded by Forp as constituting the “cardinal” scars. These are, however, very elongate, and pass from near the pedicle-groove outward, skirting the posterior portion of the lateral impres- sions, and appear to terminate in distinct, subcircular scars situated between the laterals and the lateral margins of the valve. Should this character prove of permanent value, it will be of significance as affording an analogy between Exxanta, Osoius and the Trimerellids. 78 PALHHONTOLOGY OF NEW YORK. The opposite valve shows the very peculiar feature mentioned by Mr. Bittinas, a thickened area in the umbonal region presenting the appearance of a false cardinal area inside the cavity of the umbo, a character which is sug- gestive of that in Lincutasma, but evidently of different function. This area is tripartite, bearing a deep, narrow central and two broader lateral grooves; about its anterior margin lie two broad scars of the same character as the laterals of the other valve. There are also seen the diverging furrows, which, starting at the marginal apex, pass over the edge of the thickened area, and are most deeply impressed at their anterior extremities. To homologize the muscular features seen in ELKANtA with those of OBOLELLA or any allied genus, is a difficult matter. Mr. Forp was disposed to regard the central depression of the pedicle-valve as an extravagant development of the pedicle-pit seen in O. crassa and O. chromatica. This appears very plausible, but complicates the correspondence of the other scars; and, moreover, as the internal scars of. the opposite valves do not essentially differ in their number and arrangement, it would compel the assumption of a pedicle-pit in the brachial valve.’ Mr. Forp has suggested that Watcort’s species, Obolella ? am- bigua,* from the “ Pogonip group” of Nevada, is congeneric with L. destderata. Mr. Watcort’s figures, 2a, 2e, of the interior of the pedicle-valve, indicate the unquestionable correctness of this reference. Genus PA TERULA, Barranne. 1879. PLATE IVk, FIG. 1. 1879. Paterula, BARRANDE. Systéme Silurien du Centre de la Bohéme, vol. vy, p. 110, pl. 95, figs. i, 1-3; pl. 152, figs. i, 1-9. 1884. Paterwla, Davison. General Summary to British Fossil Brachiopoda, p. 391. Diagnosis. ‘Les deux valves, circulaires ou faiblement ovalaires, ne pré- sentent qu’un bombement trés peu prononcé vers l’extérieur. L’espace interne devait done étre tres exigu. “ Ces deux valves se rencontrent habituellement isolées. Cependant, nous figurons Pl. 152, deux spécimens de valves juxtaposées, qui paraissent avoir appartenu A un méme individu. Nous pouvons ainsi constater, quwil n’existe. * Paleontology Eureka District, p. 67, pl. i, fig. 2. BRACHIOPODA. ie) aucune fissure, sur la surface ni de l'une, ni de l’autre valve. Ce fossile n’est done pas une Discina. Mais nous observons, au contraire, la trace d’une per- foration sur le bord. Elle est indiquée par une petite cylindre de la roche, qui la injectée et qui fait saillie sur le contour.” Barranps, loc. cit. Type, Paterula Bohemica, Barrande. EKtage D. The position of this genus, as far as it rests upon the character of the pedicle- aperture, appears to be near that of Scrizopoius, while the narrow internal septa diverging from the beak suggest relationship to Lepropotus. The nature of the shells is not well under- stood, but it is evident, from the description and-figures eiven by the author, that it is allied to those forms in which the pedicle-passage is in the first stages of its tran- T° %. Deena Cohemica- sition from the intermarginal obolelloid condition, to the supramarginal phase developed in SrpnonoTrera, etc. In the “General Summary the British Fossil Brachiopoda” (p. 391), Mr. Davivson has referred to this genus his species Discina? Balcletchensis, a form occurring in great numbers in the Llandeilo and Upper Caradoc, and though like the Bohemian species in the character of its broad marginal rim, no evi- dence is afforded of the pedicle or internal characters. We have received from Mr. H. M. Amr the only American specimens which we should feel disposed to refer to this genus. An enlarged figure of a gutta-percha impression taken from the best of these, is given on Plate IV k, fig. 1, and shows the conspicuous rim, the pedicle-notch, and the radiating muscular impressions taking their origin about an intramarginal callosity. This shell is from a black limestone in the city of Quebec, currently referred to the age of the Quebec group. 80 PALZZONTOLOGY OF NEW YORK. A NUMBER OF GENERA having more or less close relationship to OBoLELLA have been described by European writers, but are not at present known to have representatives in American faunas. Such are Osotus, Monozoita, Sponpy- LopoLus, Acrivis, ScumipTia, Mickwrrazta and Neosouius. The original specimens of these genera are mainly from primordial faunas, but they are to a great degree imperfectly known, the figures and descriptions given by various authors not always serving the requirements of the present status in the investigation of these fossils. Much has yet to be learned in regard to the internal charac- ters of most of them before their generic position can be established. OBOLUS, Eicuwatp. 1829. 1829. Obolus, Etcuwatp. Zoologia specialis, vol. i, p. 274. 1830. Ungula, Panpur. Beitr. zw Geogn. des Russisch. Reiches., p. 5. 1840. Orthis, Von Bucu. Beitr. zur Bestimmung der Gebirgsform. Russlands. 1847. Aulonotreta, Kurore@a (partim). Ueber die Siphonotretz, p, 278. 1848. Ungulites, Bronn. Index Paleontologicus, vol. iii, p. 1342. 1871. Ungulites, Quensrepr. Petrifactenk. Deutsch]. Brachiopoden, p. 671. Type, Obolus Apollinis, Eichwald. Unguliten-schichten. This is the best known and most thoroughly studied of all the genera above named. Externally the shells are much like those of Oxo.etna, but are generally larger.and somewhat flatter. The valves are unarticulated, both having broad, grooved cardinal areas, though the groove on the brachial valve is sometimes obsolescent. The interior of the pedicle-valve* shows a Obolus Apollinis. . : : Fic. 33. Pedicle-valve. After DAVIDSON. pair of well-defined cardinal or -posterior re 34. Brachial valve. After Kuronaa. adductor impressions, just behind the cardinal area and separated by a more or less developed median septum extending to about the center of the valve. The “laterals” are well developed and occupy a position not equivalent to the * Kurora@a and Davinson (Introd. Brit. Foss. Brach., pl. x, figs. 280-285) have not agreed in the determ- ination of the valves of Ozsotus. Of Kurorea’s figures of Aulonotreta polita (= Obolus Apollinis), those lettered 100, b/, cand d (op. cit., pl. vii), are considered by the author as interiors of the dorsal (brachial) valve, and figure e, that of the ventral (pedicle-) valve. Davipson considered, and with excellent reason, figs. 100 and 0/ as dorsal and ¢; d and e as ventral valves. BRACHIOPODA. 81 impressions in OpoLeLta which have been designated by this term, but more nearly to that of the terminal scars of the crescent in Dryozpotus. The median area of the valve on each side of the septum is much thickened, and at its anterior edge le the conspicuous central scars. In the brachial valve the cardinal and “lateral” (external or terminal) impressions are developed as in the opposite valve, and in the central region is a pair of curved impressions suggestive of, and probably corresponding to the elongate laterals in OBoLeta. These enclose an indistinct central scar. The affinities of Opotus with the linguloids are somewhat remote and general, but are seen in the character of the cardinal area and the disposition of the central muscular scars in the pedicle-valve. The strongly thickened median area of the same valve, which is given prominence by the excavated central scars, Is suggestive of a rudimentary platform such as is found with greater development in Lineutors, Lineutasma and the Trimerellids. This, however, may be an homology only, as the muscular scars in Osotus are not situated upon, but at the anterior margin of this area. The external muscular impres- sions with the ridge proceeding from them backward, toward the umbo, suggest the crescent in Dinopouus, and are the equivalents of the terminal crescent scars in that genus and the externals in Opo.etua, while the curved laterals ‘in the brachial valve show, as just noticed, the near relationship to the latter genus. A species from the St. John group, at Catun’s Island, King’s county, New Brunswick, has been referred to this genus by Mr. G. F. Marruew,* but we have, as yet, no knowledge of its interior characters, and the reference requires verification. The exterior of both valves of this shell is ornamented in the umbonal regions by a reticulated punctation which is apparently superficial. This becomes obsolete with the later growth of the shell. (See Plate IV x, fig. 22.) * O. pulcher, Matthew. Canadian Record of Science, January, 1889, p. 306. 82 PALAZONTOLOGY OF NEW YORK. Genus AULONOTRETA, Kortoraa. 1848. 1848. Aulonotreta, Kuroraa. Ueber die Siphonotretee: Verhandl. der Russ.-kais. Mineral. Gesellsch. zu St. Petersb. Jahrg. 1847, p. 278, pl. vii, figs. 10, 11. 1869. Acritis, Vorzorru. Ueber Schmidtia und Acritis, idem., 2te Ser. Bd. iv, p. 217, pl. xvii, figs. 7-9. The name AvLONOTRETA was proposed by Kurorea to take the place of Oxo.us, Hichwald, as he deemed the latter an inappropriate name. The first type- species under the description is A. polita, Kutorga, which “umfasst folgende, von Professor Eicuwaxp, aufgestellte Arten : Obolus Apollinis, O. Siluricus und ingricus, deren unterscheidende Merkmale weder mit Worten, noch mit Zeichnungen gegeben werden kénnen.”* As O. Apollinis is, however, generally recognized as a well-defined species, Kuroraa’s first type and his genus, as far as it rests on this type, became synonyms for Ozoius. The second type, Awlonotreta sculpta, Kutorga, is a synonym for the Obolus = antiquissimus, Kichwald,t and this species was taken by Vorborru as the type of his genus Acriris.t The species is very imperfectly known. Voxporrn’s figures indicate a close agreement with Oxso.us Acritis antiquissima. After VOLBORTH. Fic. 35. Interior of pedicle-valve. Fic. 36. Interior of brachial valve. in general form, and the characters of the cardinal area. The incomplete in- teriors figured show in the pedicle-valve, a broad, subquadrate median scar, crossed on its posterior portion by a transverse band connecting what appear to be cardinal scars. In the brachial valve are two subcircular scars in the median region just within the posterior margin. In the event of this form proving distinct from Oxo.us, the laws of priority require that it shall bear the name AuLonorreta, for which Acritis will then be a synonym. * Pp. 281, 282. + Urwelt Russl., 1848, p. 142, pl. iv, fig. la, b, e. t Loe. cit. BRACHIOPODA. 83 Genus SCHMIDTIA, Votzortu. 1869. 1869. Sehmidtia, Votportu. Ueber Schmidtia und Acritis: Verhandl. der Russ.-kais. Mineral. Gesell- sch. zu St. Petersb. 2te Ser. Bd. iv, p. 213, pl. xvii, figs. 1-6. Type, S. celata. Unguliten-schichten. The shells of this genus have the form and external characters of LroToBo.us, Hall. The pedicle-valve has a broad grooved area, and in the middle of the valve are two rather deep depressions separated by an elevated ridge, and having abrupt posterior margins, but with their anterior edges illy defined. These features may be compared with those seen on the interior Schmidtia celata. . +: After VOLBORTH. of Obolella polita, Hall (see plate ii, fig. 38). . F1G. 37. Interior of pedicle-valve : . . a Fic. 38. Interior of brachial valve. In the opposite valve is a median ridge, with a rather more sharply defined pair of elliptical depressions. Mr. Dau observes* that the name Scumiptia was preoccupied in 1863 for a genus of Porrrera. Genus MONOBOLINA, Satrer. 1865. PLATE IV kK, FIGS. 2, 3. ° 1865. Monobolina,-SaurErR. Mem. Geol. Survey Great Britain, vol. iii, p. 334, pl. xib, figs. 10, 10a. 1866. Obolella?, Davipsoy. British Silurian Brachiopoda, p. 61, pl. iv, figs. 20-27. 1871. Obolus?, Daviwson. British Silurian Brachiopoda, Appendix, p. 341, pl. 1, figs. 23, 24. 1884. Obolus, Davipsoy. British Silurian Brachiopoda, General Summary, p. 291. “ Section Monozorina, muscular scars united closely along the central line.” Sauter (Joc. cit.). Type, Lingula plumbea, Salter. 1859. Lower Llandeilo. The later figures given by Mr. Davinson of the interior of the type-species show that the peculiar concentration of the muscular impressions as indicated by Mr. Sauter, is strikingly different from anything seen in Oso.us, OBOLELLA, * Bull. U. S. Nat. Mus., No. 8, p. 62. 84 PALHONTOLOGY OF NEW YORK. or the allied genera. Though Mr. Davipsoy, in all his citations of the species, was in doubt as to its generic character, he did not manifest an inclination to adopt Mr. Saurer’s name; but from our present knowledge it seems that the term Monosorina must be accorded recognition. Externally the valves are covered with strong radiating strie, as in the brachial valve of ScHIZOCRANIA. Genus NEOBOLUS, Waacen. 1885. 1885. Neobolus, WAAGEN. Memoirs Geol. Surv. India: Salt-Range Fossils, pt. i, vol. iv, fas. 5, p. 756. Types, Neobolus Warthi, Waagen, loc. cit., p. 75%, pl. 84, figs. 3-8. N. Wynnii, Waagen, loc. cit., p. 759, pl. 85, figs. 1, 2. This peculiar genus from the primordial beds* of the Salt Range of India, presents some important deviations from the oboloid type of structure. In general form and outline the shell is oboloid with a somewhat transverse pos- terior margin, which is slightly thickened, and in the pedicle-valve is traversed by a broad, cross-striated pedicle-groove. The Neobolus Warthi. After WAAGEN. Fic. 39. Interior of pedicle-valve. Fie. 40. Interior of brachial valve. the figure indistinctly defined, but are seen to abut against “a short thickened ridge or knob” in the middle of the shell. Most striking are the broad mar- ginal scars occurring on both valves, and which appear to represent the external scars in Oxso.us, and the crescent in Dinozotus and its allies. In the brachial cardinal muscular scars lie close upon this groove; the central scars are faint, and in valve a strong longitudinally grooved callosity les just within the cardinal margin, and this is more or less distinctly continued into a median septum. The arrangement of the muscular scars other than those referred to, is not fully understood. * See remarks on page 29. BRACHIOPODA. 85 Genus SPONDYLOBOLUS, McCoy. 1852. 1852. Spondylobolus, McCoy. Annals and Magazine Natural History, vol. viii, p. 407. 1853. Spondylobolus, DAvipson. Introd. Brit. Foss. Brachiopoda, p. 125; pl. ix, figs. 241-243. 1855. Spondylobolus, McCoy. British Paleozoic Fossils, p. 255, pl. 14, figs. 4, 5. Types, Crania Sedgwicki, Lewis, C. craniolaris, McCoy. Lower Llandeilo. (The former species is not considered a Brachiopod by Mr. Davipson; vide Silurian Brachiopoda, p. 83, pl. viii, fig. 25.) Very little is known of this genus except from the original description given by McCoy, and the figures subsequently produced in the “ British Paleeozoic Fossils, p. 255, pl. Iu, figs. 4, 5. Mr. Davinson, from the first, expressed his doubt of its generic value, but he has reproduced the original figures in both the places cited. In the latter* he promises a further reference and explana- tion of the fossil. We have not, however, been able to find anything of later date, further than a casual mention of the name,t and even the species does not appear in any of his various lists and indexes. McCoy’s diagnosis of ‘the genus is as follows: g g “ Subcircular, slightly narrowed towards the indis- tinct, short hinge-line, nearly equivalve, flattened. Small valve with a slightly excentric apex; beneath which, on the interior, the substance of the valve is dbs 7 thickened into a wide, undefined boss. Opposite valve gic. 41. spondylodotus craniotaris slightly longer, from the apex being perfectly mar- eames. ginal and slightly produced, channeled by a narrow, triangular groove below, the anterior end of which is flanked by two very prominent thick, conical, shelly bosses, representing hinge-teeth ; substance of the valve thick, testace- ous, not glossy, minutely fibrous, but not distinctly punctated under a lens of moderate power, except by the ends of these fibres.” With our imperfect knowledge of this fossil, little can be said further than to suggest its general obolelloid appearance, and the possibility that its cardinal bosses may indicate a similar relation between it and OBoLELLA as is found to exist between the species of the genus BarrorsELia and the true Lingulas. * Expl. pl. viii, figs. 26, 27. + General Summary, 1884, p. 352. 86 PALAZONTOLOGY OF NEW YORK. Genus MICK WITZIA, Scummpr. 1888. 1888. Mickwitzia, Scumipt. Ueber eine neuendeckte untercambrische Fauna in Estland; Mém. de lacad. imp. des Sciences de St. Pétersbourg, vii Ser., tome xxxvi, No. 2, p. 24. Diagnosis. Shells large, thick, unequivalve. Dorsal valve flat, circular ; ventral valve oval, convex, produced into an acute apex, beneath which lies a triangular, more or less distinctly developed cardinal area. Valves not (?) articulated. Shell-substance Mickwitzia monilifera. x ' 7 1 na unctate After SCHMID’. composed of thin osu sely P : . Fia. 42. Pedicle-valve. Fic. 43. Interior of same valve. layers alternating with prismatic Fig. 44. Exterior of brachial valve. laminz which are traversed by scattered vertical canals. Surface covered with radiating striz. Shell composed of calcic phosphate. Type, M. monilifera, Linnarsson. This name has been proposed by Dr. Scumipr for a shell which had been described by Linnarsson in 1869,* from the Eophyton sandstone, the oldest fossil-bearing formation of Sweden, and referred at that time to the genus Lineuta (?),; subsequently by the same author in 1871,; to Oxsoxus(?). More abundant material found near Reval has shown various features which have led to its establishment as a separate genus. The shell has the general appearance of Oxous, and its relationship to this genus is shown in the external charac- ters, and the grooved cardinal area. Unfortunately none of Dr. Scumip1’s specimens give a satisfactory idication of the internal characters, so that the generic value of the species must still remain in great doubt. A remarkable feature is shown in a single figure of the interior of the smaller valve, viz, a single large tooth-like process, situated centrally behind the beak, and bent at a sharp angle backward into what would have been the umbonal region of the opposite valve.t Dr. Scummpt is not convinced that this is to be regarded as a * Ofver. af K. Vetensk. Akad. Férhandl. p. 344, t. vii, figs. 1, 2. 3 + Kongl. Svenska Vetensk. Akad. handlingar, Bnd. 9, No. 7, p. 9, pl. i, figs. 2, 3. ¢ Scumipr, pl. ii, fig. 16. BRACHIOPODA. 87 permanent feature of the species and genus (p. 22), it having been observed in but a single instance ; but should more complete material establish its persist- ence it would serve not only as a feature of generic distinction, but would remove this form far from the Oboloids (cf. Crania? Sedgwicki, Lewis: Davip- son, British Silurian Brachiopoda, p. 83, pl. viii, fig. 25, which is believed not to be a brachiopod). SCHIZOBOLUS, Utricu. 1886. PLATE III, FIGS. 11-14. 1862. Discina, Hatt. Sixteenth Rept. N. Y. State Cab. Nat. Hist., p. 28. 1867. Discina, Hatt. Paleontology of N. Y., vol. iv, p. 23. 1873. Trematis, Haut. Twenty-third Rept. N. Y. State Mus. Nat Hist., pl. xiii, fig. 20. 1886. Schizobolus, Utricn. Contributions to American Paleontology, vol. i, p. 25, pl. iii, figs. 3 a-d. Diagnosis. ‘Shell oval, depressed-convex, slightly inequivalved ; valves in- articulate ; structure calcareo-corneous. Cardinal margin somewhat thickened. “ Ventral valve with the apex at the terminus of a rather deep notch in the posterior margin; interior of the valve with two pairs of adductors, separated by a faint median ridge or septum which traverses the valve from the posterior margin, where it is bifurcated, to a point about two-thirds the length of the valve from the anterior margin. The posterior adductors are very faint. “Dorsal valve with the posterior margin straightened, the apex subterminal and but little elevated; interior of valve with a slender median septum which separates two pairs of faintly impressed muscular scars; the posterior pair large, oval and situated just in front of the cardinal margin, the anterior pair are less distinct, smaller, of triangular shape, narrowest in front, and situated near the anterior end of the mesial septum. “Very faint impressions of lateral muscles were observed near the margin of both valves.” (Utricu, loc. cit.) Type, Discina truncata, Hall. The type-species of Mr. Unricu’s genus was described first in 1862, and sub- sequently, with illustration, in 1867 (loc. cit.), as Discina truncata, from the Genesee slate of Seneca county, New York. In both these places attention was called to the fact that the muscular impressions, as far as observable, dif- fered from those of Discina. Subsequently the species was referred to the genus Trematis, Sharpe (1873, wt. cit.), on account of the sharply triangular 88 PALHHONTOLOGY OF NEW YORK. foramen on one of the valves. The New York specimens have, however, not proved so satisfactorily preserved as those of the same species from the Black shale of Kentucky, and from a study of the latter, Mr. Unricu has determined the generic relations of this interesting fossil to be quite distinct from what had been previously assumed. By the favor of Mr. Coartes Scuucuert we have had the opportunity of studying Mr. Uxricn’s type-specimens, and, in addition to these, have had access to a considerable number of specimens from the Gen- esee slate of New York. Though compelled to differ in some respects from Mr. Uxricu’s diagnosis of this fossil, our observations agree with his in most essential points. The muscular impressions and fulera are so faintly defined, even on the best preserved specimens, that allowance may readily be made for personal differences of observation ; for this reason, however, extreme care has been taken to ascertain the permanent, and eliminate the fugitive characters of this, the only species known to represent the genus. In the pedicle-valve the groove or slit is very short, sometimes appearing as a mere notch in the posterior margin, but, when well retained, comes to an acute termination at a point about one-tenth the distance across the valve. When the valve is uncompressed, this slit lies wholly on the posterior subapical slope. On the interior of this valve a faint ridge is continued forward from the proximal end of the slit, extending to a point about one-third the distance across the valve. This is flanked on each side by a low muscular callosity which narrows anteriorly and leaves the septum projecting on the median line. The margin of this callosity is grooved by distinct muscular impressions, and the groove extends about the anterior edge of the septum. The scars abutting against this callosity may be termed the centrals, and they have essentially the same character as in the genus OBoLELLA. From the post- lateral margins of the callosity extend narrow curved lateral scars, reaching to, or beyond the center of the valve, and though not always discernible they appear with great distinctness on the best preserved specimens. At the posi- tion of the cardinal scars as seen in OBpoLELLa, are sometimes depressions in the shell that may indicate the point of attachment of such muscles. BRACHIOPODA. 89 In the brachial valve, the posterior portion of the margin is considerably more flattened and that portion of the outline of the valve quite transverse. Directly within this margin, and parallel to it, is a narrow thickened band, which may be analogous to the callosity occupying a similar position in Waacen’s genus Neorotus. There is also a muscular thickening or callosity of about the same size and character as that seen in the pedicle-valve, but somewhat more flabellate, less distinctly defined, and not satisfactorily resolvable into separate scars. A faint median septum begins near the posterior margin of this area and grows in size until the anterior end is reached, whence it rapidly disappears. No evidence has been found of curved laterals similar to those in the pedicle-valve. Mr. Uxricn’s figures show in both valves peculiar circular scars situated near the lateral margins. These are mentioned in the diagnosis as being “ very faint” and indeed are visible only on the best pre- served specimens, and there only under the most favorable illumination. If it can be demonstrated that these markings actually represent muscular scars and are not the result of a slight exfoliation, they will prove a feature of much im- portance. None of the forms of OBo.E.ta, or allied genera known in primordial or Silurian faunas, show a combination of the elongate curved lateral scars with such additional impressions, and we find an analogous occurrence only in the genus Laxumina, (Hhlert, from the Salt Range of India,* a genus with a well- developed platform, remarkable not only as being the earliest representative of the Trimerellids, but also for its synthetic characters, for in association with the “ laterals,’ or outside marginal scars, which undoubtedly represent the terminal impressions of the crescent, are the peculiar curved laterals of . OpoteLta. Better material must be examined in order to determine the ex- istence or non-existence of these crescent scars in Scuizopotus. ‘This genus, with our present knowledge, appears to be a very late representative of the true obolelloid type, as pointed out by Mr. Utricu, varying therefrom more in the character of its pedicle-slit and cardinal area than in any other feature, but in its triangular pedicle-opening indicating a relationship to Trematis and ScHIZOCRANIA. * See Waacey, Mem. Geol. Survey of India, Salt Range Fossils, vol. i, pt. iv, fase. 5, p. 764, pl. Ixxxy, fig. 6, 1885; Davidsonella linguloides. 90 PALHZONTOLOGY OF NEW YORK. Externally the shell is characterized by its posterior apices, fine concentric strie, and general similarity to “ Discina.” The shell-substance is tenuous and appears to be wholly corneous. Genus DISCINOLEPIS, Waacen. 1885. 1885. Discinolepis, Waacen. Mem. Geol. Survey of India, Palzontologia Indica: Ser. xiii, Salt-Range Fossils, I. Productus-limestone Fossils, iv (fas. 5), Brachiopoda, p. 749. Diaenosis. “The shell is of very small size with two unequal valves, which are very flat, leaving scarcely any room for the animal between them. “The lower ventral valve is hardly at all vaulted in any direction, and appears flatly spread out like a small fish-scale, only the apex is a little elevated. It is removed from the margin towards the median part of the valve. The margin of the valve nearest the ie fara apex is broadly cut out by a deep incision FIG. 45. Pedicle-yalye. Frc. 46. Brachial valve. reaching to the top of the apex. “The upper or dorsal valve is in shape similar to the other one, with a slightly elevated eccentric apex, but without an incision. “The surface in both valves is either smooth or covered with a fine gran- ulation.” (Waaaen, loc. cit.) Type, Discinolepis granulata, Waagen. PI. Ixxxvi, figs. 5-7. ‘“ Obolus Beds,” Salt Range = Primordial. Genus KUTORGINA, Buttes. 1861. PLATE IV, FIGS. 10-20. 1861. Obolus, Bruunas. Geology of Vermont, vol. ii, p. 946. 1861. Kutorgina, Bruurnes. Geology of Vermont, vol. ii, p. 948 (foot-note). 1863. Obolus, Obolella, Biuncs. Geological Survey of Canada, pp. 248, 284. 1864. Obolella, Hott. Quarterly Journal Geological Society, vol. xxi, p. 101. 1865. Obolus, Obolella (Kutorgina), Brutincs. Paleozoic Fossils, vol. i, pp. 6, 8. 1866. Obolella?, Davipson. British Silurian Brachiopoda, p. 62. 1868. Kutorgina, Davipson. Geological Magazine, vol. v, p. 312. 1871. Kutorgina, Davipson. British Silurian Brachiopoda, Appendix,.p. 342. 1873. Iphidea (22), Meek. Sixth Ann. Rept. U.S. Geological Survey Terr., p. 479. 1874. Trematis 2, Wuite. Geogr. and Geol. Sury. West 100th Merid., Prelim. Rept., p. 6. 1875. Trematis?, Wuirr. Geogr. and Geol. Surv. West 100th Merid., Final Rept., vol. iv, pt. i, p. 36. BRACHIOPODA. oil 1876. Kutorgina, Linnarsson. Brachiopoda of the Paradoxides Beds of Sweden, p. 25. 1877. Kutorgina, Haut and Wuitrtetp. U. 8. Geological Exploration Fortieth Parallel, p. 207. 1883. Kutorgina, Dayipson. British Silurian Brachiopoda, Supplement, p. 212. 1884. Kutorgina, Watcotr. Paleontology Eureka District, pp. 18-21. 1885. Kutorgina, Marrunw. Illustrations of the Fauna of the §t. John Group, No. 3, p. 42. 1886. Kutorgina, Watcorr. Bulletin No. 30, U. 8. Geological Survey, pp. 101-107. 1887. Kutorgina, Waucorr. American Journal of Science, vol. xxxiv, p. 190. This genus was founded by Mr. Brtuines on certain obelloid fossils which he had previously referred to the genus Opotetna. In a foot-note to his descrip- tion of the species Obolella cingulata, he suggested* the deviation of this form from O. chromatica, in the elevation of the beak of the dorsal valve, which in his judgment implied an area and probably a foramen. The muscular impres- sions were indicated as “ two large, oval impressions faintly impressed, but still distinctly visible” with “no trace of the lateral scars.” The name Kuroraina was proposed in the event of this species not proving congeneric with O. chro- matica. Among subsequent students of these fossils, no one has given so thorough a discussion of their characters, or has had access to such complete material, Mr. C. D. Watcorr. We therefore present the diagnosis of the genus as for- mulated by him. “Shell inequivalve, transverse or elongated ; hinge-line extended nearly to the width of the shell. “Larger or ventral valve convex, elevated at the beak, which is straight or incurved, with or without a mesial sinus; area narrow, or without a true area ; when present it is divided by a wide open fissure. Smaller or dorsal valve flat or slightly convex, beak marginal. “The areas of both the ventral or dorsal valves of the species which we have showing them, are very narrow, and the fissure between them broad and rela- tively large. A number of thin longitudinal sections, cut so as to cross the beak, and also out on the cardinal edges, fail to show any covering to the fissure, and the area appears a little more than the reflexed Snell as the lines of on of the valve extend over and upon it. «Exterior of valves marked by concentric strixe or lines of growth that terminate on the camelimel Bugsy of the valves, as in Kk. NSIS nearly smooth a8 Guten of vomnone p. 948. 1861; leone Fossils, cal i, p. 9. 1865. t Bulletin No. 30, U. S. Geological Survey, pp. 101, 102. 92 PALAZONTOLOGY OF NEW YORK. and shiny, as in K. Labradorica ; like that of Tremaris, K. pannula, or Lineut- ELLA, K. sculptilis. “The interiors of the valves of the only species we have showing the interiors, K. cingulata, have numerous radiating striz: extend- ing from the beak outward toward the margins of the shell. Rutorgina cingulata, i e Alter WALCOYT. “Tn the interior of the ventral Figs. 47,48. Brachial and profile views. : Fias. 49. Interi f a brachial valve. valve four pairs of scars extend OTL MAL Aureos from the beak forward as shown in figure | d, pl. ix. “The interior of the dorsal valve is divided midway by a narrow mesial ridge that separates two pairs of scars [adductors ?|; the anterior pair small. “ Shell-structure calcareous (A. cingulata, K. Whitfieldi), or horny (K. Labra- dorica, K. sculptilis).” Type, Kutorgina cingulata, Billings. Although the foregoing diagnosis furnishes many details of this group of shells, it must be admitted that it is still insufficient to establish a satisfactory comprehension of the generic characters or taxonomic position of Kutoraina. Specimens of A’. cingulata, from Swanton, Vermont, K. Latourensis, from Port- land, N. B, and K. Prospectensis, from Lone Mountain, Nevada, which have been at our disposal, fail to add any features of importance. In this genus we meet shells often of considerable size when compared with the associated brachiopods in primordial faunas, having in the type-species at least, a high, incurved pedicle-valve with the form of an Amsocatta, and a subapical slope (‘false cardinal area”), which, according to Watcorr,* is “without the trace of an opening,” although this feature does not agree with the diagnosis above given, nor with the characters of the subapical area in other species referred to the genus, where the open fissure appears to begin at the apex and widen downwards, having very much the character seen in the genus Orruts. The opposite valve, with its highly elevated marginal apex and very slightly developed area, can come into contact with the pedicle-valve only at * Bulletin No. 30, U. S. Geological Survey, p. 103. BRACHIOPODA. 93 the extremities of the cardinal line, thus leaving a great gap between the valves, into which the pedicle-fissure merges. This feature, if established, is without an homologue among the brachiopods, although its function may be regarded as a means of passage for the pedicle similar to that found in all the biforate articulated brachiopoda. It does not appear from the descriptions of other species of Kurorera that the brachial valve is as elevated as in K. cingulata, but it is yet to be ascertained how far the apparent flatness of this valve has been due to pressure in fossilization. Mr. Marruew, in the description of his species, K. Latourensis,* has mentioned the existence of “(a minute tooth on each side of the very narrow and small foraminal opening.” But this important character requires verification, for not only are the St. John specimens of Kurorerina small and fragile, but have usually been subjected to more or less distortion, which might readily develop irregularities easily mistaken for permanent features. The general character of the umbonal region in the pedicle-valve would in- dicate a certain degree of similarity in Kuroreina and Acrorreta. In the latter genus the furrow on the cardinal slope appears to have been due to the closing of the pedicle-aperture by the progressive accretions to the shell, in- volving a modification of the surface and its concentric growth-lines; while in Kurorcina the primitive apical aperture has been left unclosed. The internal or muscular impressions are also imperfectly known and at present furnish no assistance in establishing the affiliations of the genus. A very close ally of Kurorata, in size and all external features except the cardinal characters of both valves, is the Russian genus Voisorruia, von Moller (q. v.). The latter has full, rounded umbones on both valves, and the high area of the pedicle-valve is crossed, not by an open fissure, but by a convex ridge ; the shell is described as having no foramen. ‘The beak of the brachial valve lies close against the cardinal edge of the opposite valve, leaving no hiatus as in Kuroreina. Under the notice of the genus ScaizopHouis, Waagen, we have referred to the similarity of its type-species and Kutorgina Latourensis, Matthew. * Illustrations of the Fauna of the St. John Group, No. 3, p. 42. 1885. 94 PALHONTOLOGY OF NEW YORK. Of Kurorctna the following species have been described by American au- thors: K. cingulata, Billings (loc. cit.); K. sculptilis, Meek (Iphidea?? sculptilis, Meek, referred to Kuroraina by Mr. Watcor1™®); K. pannula, White (Trematis ? pannulus, White, referred to Kutoraina by Mr. Watcorty) ; NG minutissima, Hall and Whitfield ; Mr. Watcorr§ makes this name a synonym for K. sculp- tilis ; K. Prospectensis, Walcott ;|| K. Whitfieldi, Walcott; K. Labradorica, Bil- lings,** = Obolus Labradoricus, Billings, referred to Kutorcina by Mr. Watcorr; K. Latourensis, Matthew ;++ K. pterineoides,tt Matthew. In 1868, Davipson identified the species Obolella Phillipsi, Holl, from the Lingula Flags and Lower Tremadoc, as K. cingulata, Billings, and im 1876, Liy- naRsson described from the Paradoxides beds of Sweden a similar form as K. cingulata var. pusilla. All the representatives of this genus known are from primordial faunas. Genus SCHIZOPHOLIS, Waacen. 1885. 1885. Schizopholis, WAaGEN. Mem. Geol. Sury. India. Paleontologia Indica: Ser. xiii, Salt-Range Fossils, I. Productus-limestone Fossils ; iv (fas. 5), Brachiopoda, p.752. “The shells belonging to this genus are all of very small size. They con- sist of two valves, of which one is imperforated and rather flat, the other is slightly elevated with a somewhat prominent marginal apex, below which is a small triangular area slit open in the middle by a triangular fissure, which seems to be sometimes a little widened at the top, forming a kind of foramen, placed just at the extremity of the apex. “The shell-surface is finely granular, and it seems as if it had borne spine- like appendages as in SrpHonoTrETA, but these are not preserved in any of the specimens at my disposal. “Of the internal characters of the genus nothing is known to me, as*there are only three specimens available ; and as the rock, a black micaceous shale, * Paleontology Eureka District, p. 20. + Bulletin No. 30, U. 8. Geological Survey, p. 105. { U.S. Geological Exploration Fortieth Parallel, vol. iv, p. 207, pl. i, figs. 11, 12. § Paleontology Eureka District, loc. cit. | Paleeontology Eureka District, p. 19, pl. ix, figs. 1a, b. q| Paleontology Eureka District, p. 18, pl. ix, figs. 4, 4a. ** Paleozoic Fossils, vol. i, p. 6. tt Illustrations of the Fauna of the St. John Group, No. 3, p. 42, pl. v, figs. 18 a-c. tt Illustrations of the Fauna of the St. John Group No. 3, p. 43, pl. v, fig. 19. BRACHIOPODA. 95 adhered very firmly to the internal side of these shells, it appeared impossible to make a preparation of the inside.” (Waacen, wt. cit.) Type, Schizopholis rugosa, Waagen, pl. Ixxxvi, figs. 2-4. Obolus Beds, Salt Range = Primordial. This genus, represented by a single species, is placed by Dr. Waacen, with unquestioned accuracy, among the Siphonotretids. Its closest alliance is with Kuroreina, or with those species of that genus which have afforded definite evidence of an open fissure on the subapical area, i. e., K. Latourensis, Matthew, K. pannula, White.. This feature has already been given among the generic characters of Kuroreina, but it may be held subject to reservation, since positive evidence of its existence in the type-species, K. cingulata, Billings, is still wanting. The resemblance senizopnotis rugosa. . . " . After WAAGEN. between K. Latourensis and Schizopholis rugosa is most rie. 50. Pedicle-valve, front . view. striking in every essential respect, and should the former Fre. 51. Cardinal view. not prove congeneric with K. cingulata, it must be referred to ScwizoPHo.is; conversely, if these species are congeneric, it would appear that ScizopHo.is must be considered a synonym for Kurorarna. Genus VOLBORTHIA, von Motter 1873. 1847. Acrotreta, Kurorega. Verbandl. Kais. Mineral. Gesellsch. zu St. Petersburg, p 277, pl. vii, fig. 9. 1873. Volborthia, von M6uter. Verhandl. Kais. Mineral. Gesellsch. zu St. Petersburg, pl. vii, fig. 9. 1874. Volborthia, voy Métter. Neues Jahrb. fiir Mineralogie, ete., Heft 5, p. 449, pl. vii, figs. 1-6. Type, Acrotreta recurva, Kutorga. Lower Silurian (= Primordial ?). The, genus is founded on the third of Kurorea’s species of his genus Acrorreta, a form of very large size compared with the type of the genus. Kurorea’s description covers only a_ single pedicle-valve, from which the apex was broken. The better examples described by von MOLLER show that the shell-substance is calareo-corneous Volborthia recurva. , ne » ct After VON MOLLER. and finely punctate. In general form the shell Shee Gea suggests a “cornucopia, the mouth of which is Spe EEE 96 PALHVONTOLOGY OF NEW YORK. closed by a very convex cover. Viewed from above, the outline of the shell is transversely oval, the posterior margin, the length of which has about one- half the diameter of the shell, being straight. The ventral valve is elevated and conical, and possesses an incurved and inflated umbo with no foramen. Between the beak and the posterior margin is a sharply defined, elevated, tri- angular area, which is divided by a low, convex ridge passing from the beak to the margin. “The dorsal valve is convex, though much more depressed than the ventral, and has a beak similar to that of the latter. Although this beak lies in the same vertical line with that of the opposite valve, it rests directly upon the posterior margin of the valve, and has no area. The surface of the valves is smooth and covered only by fine concentric lines, which are continued without interruption over the area of the ventral valve. * i ae eo - “Neither valve appears to possess any internal apophyses, at least the inter- nal casts show no trace of them. The muscular impressions are unknown, the casts showing only a small number of widely divergent radiating lines.” (von Mouuer, ut. cit.) The similarity of this shell to Kuroratna in general form and surface-features, is at once apparent. We meet, however, a conspicuous difference in the areal ridge of Votportuta, a feature strongly suggestive of the ‘“ pseudo-deltidium ” of the articulate brachiopods. It is precisely similar to the areal ridge in IpuipgeA, and the exact counterpart in form of the areal furrow in AcRoTRETA ; its origin may be similarly explained, and a complete analogy may be found, in this respect, in the genera with the foramen-scar ecurved as in VOLBORTHIA and Ipuippa, incurved as in Acrotreta and Conorreta, and open as in Kuror- Gina and Scuizopnouts. While we must admit the absence of an external fora- minal aperture in the material so carefully studied and satisfactorily illustrated by Professor von Méuinr, we are led to surmise that this character, often so obscure and difficult of detection in such fossils, will eventually be found. The shells of Votsorruta, like those of Kurorartna, are of very considerable size, an example cited having a length of 14 mm., a width of 19 mm. and a height of 16 mm. BRACHIOPODA. 97 Genus ILPHIDEA, Bituines. 1872. PLATE IV, FIGS. 6-9. 1872. Iphidea, Binurnes. Canadian Naturalist, New Series, vol. vi, p. 477. 1874. Iphidea, Bituines. Paleozoic Fossils, vol. ii, pt. i, p. 76. > 1876. Iphidea, Linnarsson. Brachiopoda of the Paradoxides Beds of Sweden, p. 25. 1886. Iphidea, Waucorr. Bulletin No. 30, U. S. Geological Survey, p. 100. : Diaenosts. “Of this genus we have no specimens showing the internal structure, but the external characters seem sufficient to separate it from any described generic group. The ventral? valve of J. bella is conical, strongly elevated at the beak, hinge-line nearly straight, posterior angles narrowly rounded, sides and front nearly uniformly rounded, forming rather more than a semicircle. Posterior side with a large false area and a convex pseudo-delt- idium, the width of which at the hinge-line is nearly one-third the whole width of the shell. The dorsal valve is semicircular, moderately convex, most elevated at the beak. The hinge-line appears to be straight. * i z The surface is covered with fine concentric strize, which in the ventral valve are continued around on the area.”’* Type, Iphidea bella. The foregoing diagnosis is derived from the original description of the type- species, Iphidea bella. After the lapse of eighteen years since the date of its publication little has been contributed to our knowledge and no facts of essential importance bearing upon the external characters of these shells; of the interior we still know nothing. In 1875, Mr. Musk described the species Iphidea (??) sculptilis,; from the Gallatin River, Montana, but as the hinge-line and subapical area of the shell have not been observed, and on account of its apparent specific identity with the Kutorgina minutissima, Hall and Whitfield, it has been referred provisionally to the genus Kuroramva by Mr. Watcorr, and the latter species reduced toa synonym. Dr. Linyarsson described the species I. ornatella, from the Paradoxides beds,{ giving good figures of the exterior of * Binuines. Canadian Naturalist, 1872, loc. cit. } Preliminary Paleontol. Rept.: Sixth Ann. Rept. U. 8. Geological Survey 'err., p. 479. { Paleontology Eureka District, p. 20. § Brachiopoda of the Paradoxides Beds of Sweden: Bibang till K. Svenska Vet Akad. handlingar, Bnd. 3, No. 12, p. 25, pl. iii, figs. 42, 43. 98 PALHHONTOLOGY OF NEW YORK. both valves, and it would be difficult to indicate essential differences in the general form and proportions of this species and I. bella.* Notwithstanding the fact that our knowledge of these shells is so circum- scribed, certain of their features are of definite generic value. The apical foramen indicates the close alliance of the genus with Acrorrera and AcROTHELE, and may be considered as an inter- mediate stage in the forward progress of the pedicle-aperture from its intermarginal position in the linguloids and oboloids, to its ™¥,>4: feMdce dala. _ excentric position and tubular character in ScuizamBon. The flattened subapical slope is a feature also seen in Acrorreta, while the convex foraminal covering on this area, which gives to the shell an appearance so suggestive of ORTHISINA, is found in the inarticulate brachiopods only here and in VotBorruta. The shell- substance is corneous, apparently consisting of but few layers. The originals of Mr. Brttines’ I. bella were from Trois Pistoles, near Quebec ; “a closely allied species of the same genus occurs in the primordial limestone at Topsail Head, Conception Bay, Newfoundland” (Bixuines, loc. cit.). The specimen here figured on Plate IV (figs. 8, 9), is from Georgia, Vermont. We have before us specimens of a species from the Grand Canon, Arizona (Tonto group of Watcorr== Potsdam sandstone ?), which bears a more promi- nent areal ridge than J. bella, and has the cardinal edge elevated above the rest of the margin of the valve, a feature strongly marked in Linnarsson’s species, I. ornatella. Genus ACROTHELE, Linnarsson. 1876. PLATE IU, FIGS. 25-31. 1868. Lingula, Hartr. Dawson’s Acadian Geology, Second Edition, p. 644. 1876. Acrothele, Linnarsson. On the Brachiopoda of the Paradoxides Beds of Sweden, p. 20. 1879. Obolus?, BARRANDE. Systéme Silurien du Centre de la Bohéme, vol. y, pl. 102, fig. vii. 1879. Discina, Barranpe. Systéme Silurien du Centre de la Bohéme, vol. v, pl. 110, fig. vii. 1881. Acrothele, Waite. Proceedings United States National Museum, vol. iii, p. 47. 1883. Fie. 58. Internal cast of Fic. 59. Interior of brach- pedicle-valve of this species give it a great brackial valve. ial valve. elevation and an indistinct cardinal area, though they do not show the apical foramen. It is highly probable that the species will prove an AcRoTRETA. The vertical groove on the cardinal area is, like the elevation and definition of the area itself, a very variable feature. In A. subconica, A. gemma, and A. Nicholsoni it is sharply defined, while A. disparirugata, Kutorga, A. Baileyi Mat- thew, and A. socialis, von Seebach, bear less definite indications of this character. The suggestion offered by Kutorea, that this furrow may be taken as an “ in- dication of a deltidium,” may be understood as not implying more than a remote homology with the deltidium of the articulate brachiopods. We have yet but few American representatives of this genus. In 1865, Mr. Bittines described the first known American species, A. gemma, and Mr. Wat- cott (1884) has considered the species regarded by Merk (18/2) as A. subconica, Kutorga,t from the Gallatin River, Montana, and the A. pyzidicula, White (1874), from Nevada, as synonymous with it. Acrothele? dichotoma, Walcott (18 4), from Nevada, has been subsequently referred by its author (1886) to Acro- TRETA, while Acrotreta subsidua, White (1874), is referred to AcrotugLte. Mr. Marruew has described (1885) Acrotreta Baileyi and A. ? Gulielmi, from the St. John group; the latter of these is a representative of a distinct genus, which is discussed in the following pages under the name Discinopsis. All the American species are from primordial faunas; A. socialis, von Seebach, is * Illustrations of the Fauna of the St. John Group, No. 3, pl. y, fig. 13. + British Silurian Brachiopoda, Supplement, pl. xvi, fig. 27d. { This form Mr. MEEK proposed to name A. attenuata, in case it proved distinct from the Russian species. 104 PALAZONTOLOGY OF NEW YORK. from the Paradoxides Beds; A. subconica and i i —_ Lingoulella Lingula = Lingulepis Vi Lingulops —— Lingulasma f Trimerella U : 4 Monomerella Glossina Dinabolee ; U Rhinobolus Returning to the genus OxoeLLa, we find it also an important point of divergence. BRACHIOPODA. 165 As suggested above, certain linguloid characters, in which form and the structure of the pedicle-passage are paramount, have departed toward Lineuta by the way of Lineuterta. Another combination of linguloid features, in which the muscular scars are of primary importance, but the form still obolel- loid, is represented by the genus Osotus. Here the muscular bands have become specialized to such a degree that in the pedicle-valve they approach closely to Lingua, while in the other they retain more distinctly the obolelloid character ; moreover, the subcircular form and the persistence of the pedicle- groove on both valves are features of OBOLELLA. Oxotus, therefore, is a more specialized form than Oxso.etta and less so than Lineuta. The aberrant Neopotus appears to hold intermediate structural rela- tions to both Osotus and OBoLeLa, except in the existence of a strong cardinal process in the brachial valve, a feature indicating progress in this line of derivation, toward characters of the articulate brachiopods. The typical combination of obolelloid characters is continued, without essen- tial variation, into the genera Leprosotus and Scumipt1a, while Pareruna, whose structure demonstrates its close alliance with Leproso.us, presents a new feature of great importance in its minute, incised, marginal pedicle-aperture. In Scuizosouvs we find the same features superinduced upon the substantially unaltered muscular scars of OBOoLELLA. While discussing the origin and development of the platform in the inarticu- late brachiopoda, we have referred to the fact, that Osonus, in having its muscular scars excavated, as in Lineua, and not elevated on a central thicken- ing, as in the other forms constituting the linguloid line of development toward TRIMERELLA, holds the same relation to the genus Exkanta, as does Lineuta to Lineutors. Further, that Eixania represents, by virtue of this variation, an important progress in the development of trimerelloid characters along the obolelloid line, connecting with TrimereLLa by way of Dinosotus. There is no single feature in the entire group of the edentulous brachiopods so striking as the great platform in TRIMERELLA and its allies, and it is rarely that so beautiful and well-established an illustration of the attainment of such a remarkable re- sultant along two distinct lines of development can be presented. 166 PALZEONTOLOGY OF NEW YORK. The immediate variations from the obolelloid stock, may be expressed as follows : Schmidtia Paterula Schizobolus —— | Ae Share Leptobolus fin eelaee a Me Obolella ——— $$ Lingulella Lingula fa a o 2 ic ise] =] 4 Bg > 8 2 So oe g Sees 1S 8 8 & rae} S 2 m 8 8 oa = ic3I 3 es) 2 5 Gy Ae oe = iS = a 4 ' > > =) 2 ~ on Se sat AoE 7 Se \ a g ey ' oe ' 1 ‘VITGLUGds ‘SIHLUONI(T, ‘SANOISWTqg ‘STHLYOLOGT J “plBM POON ‘2 CINLIO |- “(peyorset sv) weed ‘SIHLYC, bo bo Ne) ae EE Se Lower Cambrian. Middle Cambrian. Upper Cambrian. Calciferous. Chazy. Trenton. Utica. Hudson River. Clinton. Niagara. Lower Helderberg. Oriskany. Upper Helderberg. Hamilton. Chemung. Waverly. Burlington. Keokuk. St. Louis. Kaskaskia, Chester. Lr. Coal Measure. Middle and Upper Coal Measures. | Permian. Triassic. 230 PALHONTOLOGY OF NEW YORK. Genus BILLINGSELLA, Gen. nov. PLATE VIIJ4, FIGS, 1-9. 1857. Orthis, Binuincs. Report Geological Survey of Canada, p. 297. 1861. Orthisina, Binuines. Geology of Vermont, vol. ii, p. 949, figs. 350-352. 1861. Orthisina, Bruuinas. Palzeozoic Fossils, vol. i, p. 10, figs. 11, 12. 1862. Orthisina, Binuines. Paleozoic Fossils, vol. i, p. 138, fig. 115. 1863. Orthis, Haun. Sixteenth Rept. N. Y. State Cab. Nat. Hist., p. 134, pl. vi, figs. 23-27. 1863. Orthisina, Buuines. Geology of Canada, p. 284, fig. 289. 1867. Orthisina, Haut. Trans. Albany Institute, vol. v, p. 113. 1882. Orthis, WurrrieLp. Geology of Wisconsin, vol. iv, p. 170, pl. i, figs. 4, 5. 1883. Orthis (Orthisina ?), Hatt. Report of State Geologist N. Y., pl. xxxvii, figs. 16-19. 1884. Orthisina, Wuirrietp. Bulletin Am. Museum Nat. Hist., vol. i, p. 144, pl. xiv. fig. 6. 1886. Orthisina, Waucorr. Bulletin No. 30, U. S. Geol. Survey, pp. 120-122, pl. vii, figs. 5-7. This term is proposed to include certain species, few in number, according to present knowledge, which have some decided external resemblance to OrrHts and CrrtamBonrres (—OrvuistNna), but which must be excluded from these genera on the basis of internal characters. The form taken as typical of this genus is Orthis Pepina, Hall, of the Potsdam sandstone of Wisconsin ; other examples are Orthisina festinata, Billings, O. orientalis, Whitfield, and O. transversa, Walcott. Dracnosts. Shell transverse ; subquadrate or semicircular in outline. Con- tour concavo- or plano-convex. Surface sharply striate or plicate. Pedicle- valve the more convex; cardinal area moderately high, vertical or slightly incurved. Delthyrium covered by a convex plate, which, in rare instances, may be minutely perforated at the apex; the teeth are well developed, but the dental plates are continued along the bottom of the umbonal cavity, enclosing a small subelliptical muscular area near the apex. In the brachial valve the cardinal area is greatly inclined, making an obtuse angle with that of the opposite valve. The delthyrium is partially covered by a convex deltidium which never attains the development seen in the opposite valve, and is often wholly absent. Type, Orthis Pepina, Hall. Potsdam sandstone. Osservations. From the foregoing description it is evident that the characters of this group are essentially orthoid. The shells are, however, all small and bear in common an expression unlike that of Orruis, while the presence of a highly developed arched deltidium is a feature showing positive BRACHIOPODA. 231 relationship to CiiramBonirEs, as does also the concave plate in the delthyrium of Protorruts Like Prororruts, this genus includes a series of primordial species antedating both Orrais and Curramsonires, but apparently having attained about the same stage in the line of development toward these genera. To the species above mentioned may probably be added the Streptorhynchus ? primordiale, Whitfield,* from the Calciferous beds at Fort Cassin, and Orthisina grandaeva, Billings,t from the Chazy. In the lower beds of the Upper Silurian of the Anticosti series occurs the Orthis ? laurentina, Billings, a shell with the interior characters, and the exterior expression of Orthis calligramma, differing only in the presence of deltidia upon both valves, and in this respect resembling BILLinGsELLA and CLITAMBONITES. Genus PROTORTHIAS, Gen. nov. PLATE VILA, FIGS, 14-21. 1868. Orthis, Hartr. Dawson’s Acadian Geology, Second Edition, p. 644, fig. 233. 1884. Orthis, Waucotr. Bulletin No. 10, U. 8S. Geological Survey, p. 17, pl. i, figs. 1, 1a-d. 21884. Orthis, Waucorr. Monogr. U. 8. Geological Survey, vol. viii, p. 22, pl. ix, figs. 8, 8 a. 1886. Orthis, MatrHew. Transactions Royal Society of Canada, Sec. IV, p. 43, pl. v, figs. 20 a-c; (2) p. 42, pl. v, figs. 18 a-c. There is a small group of shells passing under the name of Ortuis which should be separated from that genus, and given a new designation, since none of the existing generic groups can properly receive them. Their distinctive characters are as follows: Diaenosts. Shells small, transversely subquadrate or semicircular. Hinge- line straight, its length being equal to the greatest width of the valves. Valves unequally biconvex, or sub-planoconvex, the pedicle-valve being the larger. The cardinal area is narrow on both valves, but is higher on the pedicle-valve, and is transected by a broad delthyrium which is closed below by a concave plate apparently produced by the union of the dental lamelle, which are not continued to the bottom of the valve; teeth distinctly developed. In the brachial valve the cardinal area also bears an open delthyrium; the dental * Bulletin No. 8, American Museum of Natural History, p. 301, pl. xxiv, fig. 7, 1886. + Canadian Naturalist and Geologist, vol. iv, p. 349. 1859. 232 PALAZONTOLOGY OF NEW YORK. sockets are obscure and the crural plates small; the latter appear to unite and form a low elevation across the base of the delthyrium. Cardinal process absent or rudimentary in all the specimens examined. Muscular markings in both valves extremely obscure. Surface marked by distinct plications, with interstitial finer radii, which are crossed by delicate concentric strive; these are usually accompanied by a low sinus and fold on the brachial and pedicle-valves, respectively ; interior very finely papillose. Shell-substance fibrous and apparently punctate. Type, Orthis Billingsi, Hartt. St. John group. Mr. G. F. Marruew has kindly furnished an abundance of specimens for the study of Orthis Billingsi, Hartt,* and Orthis Quacoensis, Matthew, from his Division I of the St. John group. These species are congeneric, and it is possible that Mr. Waucori’st Orthis Eurekensis, from the Prospect Mountain group, Nevada, belongs to the same genus. It has already been observed that Biuiines’ species, O. Mycale and O. Tritonia, from the Lévis formation, are also without evidence of a cardinal process; but it is impossible to say whether they agree with O. Billingsi in other respects. . The characters of the St. John species are eminently comprehensive ; first, the form of the shell is one more frequently met with among the strophome- nids than among the orthids; the concave plate formed by the union of the dental lamellee is never found in Orruis proper, though occurring in Scen- iptum. In Orruisina or CirtamBonirss this plate is always present, but always supported by a median septum and invariably accompanied by the convex del- tidium, which, so far as known, does not exist in Prorortuis; while in the group typified by Orthis Pepina, Hall (here designated by the term BILLINGsELLA), the convex deltidium of CritaMBonIrTEs is present and the concave or dental plate absent. The apparent absence of a cardinal process in PRorortTHiIs may be due to the imperfections of the fragile shells studied. The specimens of the * Harr, Dawson’s Acadian Geology, Second Edition, p. 644, fig. 223. 1568. Watrcorr, Bulletin No. 10, U. S. Geological Survey, p. 17, pl. i, figs. 1, La-d. 1884. + Illustrations of the Fauna of the St. John Group, No. 3. 1885. Trans. Royal Soc. Canada, Sec. IV, p. 43, pl. v, figs. 20 a-c. 1886. t Paleontology of the Eureka District, p. 22, pl. xi, figs. 8, 8a. 1884. BRACHIOPODA. 233 St. John shells are preserved as external and internal casts, and from some of these there is reason to infer that the substance of the shell was punctate. Mr. Marruew, in a private note, intimates that his Kutorgina Latourensist may belong to the same group of shells. This species has been discussed in the preceding pages, under the genus Kuroreina,{ and although an examination of the more complete material received from Mr. Marruew, with his identifica- tion, has not proved entirely conclusive, there are reasons in favor of adopting the views of this author. Genus CLITAMBONITES, Panpzer. 1830. PLATE VII, FIGS. 23-28; anpD PLATE XV 4, FIGS. 1-8. 1822. Anomites, ScHtoTHEIM. Nachtrage zur Petrefactenkunde, p. 65, pl. xiv, fig. 2. 8. Orthis (partim), DAtmMan. Kongl. Svenska Vetenskaps-Akad. Handl. for 1827, p. 111, pl. ii, fig. 1. 1830. Klitambonites, Panper. Beitrage zur Geognosie des russ. Reiches, p. 70, pl. iii, fig. 14; pl. xxviii, figs. 16, 17, 23, 24 (generic figures). 1830. Pronites, PANDER. Beitraége zur Geognosie des russ. Reiches, pp. 71-74, pl. xxviii, fig. 16 (gen- eric figures) ; pls. xvi, xvii, xviii, xxiii, xxiv, xxvi. 1830. Hemipronites, PanpreR. Beitrége zur Geognosie des russ. Reiches, pp. 74-76, pl. iii, fig. 14; : pl. xxviii, fig. 18 (generic figures) ; pls. xviB, xvill, xxii, xxiv. 1830. Gonambonites, PanpER. Beitraége zur Geognusie des russ. Reiches, pp. 77-80, pl. ili, fig. 1; pl. xxviii, fig. 15 (generic figures) ; pls. xv, xviA, xViB, xx, Xxv. 1837. Orthis, von Bucu. Abhandl. der k. Akad. Wissenschaft. Berlin, p. 63. 1836. 1840. Orthis, von Bucu. Beitraége zur Bestimm. der Gebirgsformation Russlands, p. 20. 1840. Orthis, von Bucu. Mem. Société Géologique de France, vol. iv, pp. 208-211. 1840. Orthis, von Etcuwautp. Urwelt Russlands, pt. i, p. 15. 1840. Orthis, voy Eicuwaup. Ueber das Silur. Schichten-System von Estland, p. 148. 1842. Orihis, von Etcnwatp. Urwelt Russlands, pt. ii, p. 145, pl. iv, fig. 11. 1845. Orthis, pe Vernevin. Géol. de la Russie et de Mont. de l’Oural, pp. 198-206, pl. xii, figs. 1-4. 1846. Clitambonites, Acassiz. Nomenclator Zoologicus; Index Univer., p. 90. 1847. Orthisina, D’ORBIGNY. Comptes rendus, vol. xxv, p. 267. 1847. Orthisina, D’OrBiany. Ann. Science Nat., vol. viii, p. 268, pl. viii, fig. 7. 1850. Orthisina, D’ORBIGNY. Ann. Science Nat., vol. xiii, p. 319. 1850. Orthisina, D’ORBIGNY. Prodrome de Paléont. stratigraph. univ., p. 16. 1852. Orthisina, McCoy. British Paleeozoic Fossils, p. 231. 1853. Orthisina (partim), Davipson. Introd. British Fossil Brachiopoda, p. 104. 1859. Orthis, von Etcnhwatp. Lethza Rossica, vol. i, p. 838. 1865. Orthisina, SHater. Bulletin No. 4, Museum Comparative Zoology, p. 67. 1871. Orthisina, Davipson. British Silurian Brachiopoda, p. 278, pl. xlix, figs. 27-29. 1878. Hemipronites, Wuirrretp. Ann. Rept. Geol. Survey of Wisconsin, for 1877, p. 72. 1882. Hemipronites, Wuirrietp. Geology of Wisconsin, vol. iv, p. 243, pl. x, figs. 15-17. 1883. Orthisina, Davipson. British Silurian Brachiopoda ; Suppl. p. 175, pl. xvi, figs. 16-18. 1887. Clitambonites, Giuterr. Fischer’s Manuel de Conchyl; Brachiopoda, p. 1289. * Illustrations of the Fauna of the St. John Group, p. 42, pl. v, figs. 18 a-c. t See page 93, plate iv, figs. 18-20. 234 PALAZONTOLOGY OF NEW YORK. Diagnosis. Shells with a subsemicircular marginal outline; convex or subpyramidal in the typical group. Hinge-line straight, and forming the greatest diameter of the shell. Pedicle-valve elevated, cardinal area high, ver- tical, or sometimes incurved, and crossed by a broad delthyrium, which is normally covered by a convex, perforate deltidium. On the interior of the valve the dental lamelle are very strongly developed, converging and uniting in the median line before reaching the bottom of the valve; thus forming a spondylium,* which with the deltidium encloses a conical subrostral vault. This plate is supported by a median septum extending for about one-half the length of the valve. Muscular impressions obscure. In the brachial valve, the cardinal area is considerably developed, and the delthyrium filled by a con- spicuous callosity, against the inner side of which the simple orthoid cardinal process abuts. The dental sockets are large, the crural plates low and continu- ous with the edges of the delthyrial callosity. A thickened transverse area is formed in the umbonal region by the union of the inner portions of the crural plates with the cardinal process, and thence a broad median ridge is continued forward through the muscular area, which is sharply defined and quadripartite. External surface covered with radiating strie. Shell-substance impunctate. Type, Pronites adscendens, Pander. Lower Silurian. American example, Orthisina Verneuili, von Eichwald. Trenton limestone. Oxsservations. Although p’Orpieny’s term, Orruisina, has found its way into general use for this group of shells, there is no reason why it should replace the name Ciiramponirss, a genus clearly defined and abundantly illustrated by its author. In order to show PanpgEr’s conception of this group, and since his — “ Beitriige zur Geognosie des russischen Reiches” is a work not generally ac- cessible to American students, his original descriptions and typical figures are here introduced. + * YrovdvAvoy, vertebra. This term will apply with equal propriety to the similar plate existing in the pedicle-valve of other brachiopods, e. g., CLITAMBONITES, PENTAMERUS, CAMARELLA, STENOSCHISMA, etc. + PanpEr’s determinations of genera and species of brachiopoda evince a remarkable insight and ana- lytical power. He was in this regard a generation in advance of his contemporaries, who apparently felt it their duty to throw both his genera and species back into the old groups whence they were derived, and thus totally ignore his work. The inaccessibility of PANDER’s works to western students, has been one great cause of the misunderstanding of many brachiopodous genera. BRACHIOPODA. 235 “ KrrramBonites. Die Schlossfliiche der oberen Schale bildet ein vollkom- menes Dreieck, dessen Grundfliiche an der Beriihrungsstelle derselben mit der unteren Schale sich befindet, und dessen Spitze schrig oder gerade nach oben gegen die Oberfliiche hinaufsteigt. In der Mitte dieses grésseren Dreiecks findet sich noch ein kleineres, das gew6lbt nach aussen hervortritt und das wir, in so fern es von aussen die zum Schlosse gehérigen Theile beschiitzt, mit dem Namen des Schlossdeckels belegen wollen. Die Schlossfliiche der unteren Schale ist fast geradlinig, ragt etwas nach aussen hervor und bildet in der Mitte einen Wulst, zwischen welchem und dem Schlossdeckel die bald sichelférmige, bald dreieckige Oeffnung zum Durchgange des fleischigen Stieles sich befindet. Die vier Seiten der Schalen sind hier am deutlichsten ausgesprochen, die Oberflichen sind wenig gewolbt, gewohnlich verliiuft die der oberen Schale von der Spitze der Schlossfliiche, welche hiufig den héchsten Punkt bildet, schrig nach vorn und gegen die Seiten sich abfliichend fort. Der Queerdurchmesser ist gew6hn- lich der vorwaltende. “Die feinen Lingsrippen werden durch concentrische, unter einander und mit der Brust und der Seitenlinien parallel laufende, Streifen unterbrochen, so dass erstere treppenartig, selbst etwas dachziegelartig auf einander zu liegen kommen. Die Brustlinie ist in der Queere im Allgemeinen gerade, selten und auch dann nur unbedeutend gegen die Oberschale sich hinaufbeugend. Da aber hier doch sehr grosse Verschiedenheiten sowohl in Riicksicht der Wélbung, als der Durchmesser und der Héhe der Schlossfliche vorkommen, so wird es bequemer sein, die Klitamboniten noch in zwei Abtheilungen zu trennen, welche sich hauptsichlich dadurch unterscheiden, dass bei den einen, die wir Proniten nennen, die obere Spitze des Dreiecks der Schlosstliiche den hochsten Punkt in der Schale erreicht, wiihrend bei den Hemiproniten letztere zwischen der Riickenfliche und der Brustlinie fillt, erstere also niedriger ist.”* Figs. 1, 2, 3. Pronites udscendens. After PANDER. * « = eS) = a cae wv | ro) o wn sas] q — 4 le>| a ° Se ed ey L a = S) & 2 a 5 aos 4 = is » a 4 is3) Z Soa Lan NA la ye} ' = cc = wa ee) D7 S a, 2 ot ee Ser a a) : 9 @ iS 2 2 ® ‘iis ae ae aS ' ' a = > <3. ' oO = =" oO ' 1 ' i=) S BRACHIOPODA. ‘WOIGIHLYUC 275 ‘® CININOHdOUL yy ‘AuvUIION ‘[OJIG OY} Jo wetmoasg Lower Cambrian. Middle Cambrian. Upper Cambrian. Calciferous. Chazy. Trenton. Utica. Hudson River. Clinton. Niagara. Lower Helderberg. Oriskany. Upper Helderberg. Hamilton. Chemung. Waverly. Burlington. Keokuk. St. Louis. Kaskaskia, Chester, Lr. Coal Measures. Middle and Upper Coal Measures. Permian. Triassic. 276 1769. 1821. 1823. 1826. 1828. 1834. 1837. 1837. 1837. 1839. 1840. 1841. 1841. 1842. 1842. 1843. 1843. 1844. 1844. 1845. 1846. 1847. 1847. 1848. 1848. 1850. 1852. 1856. 1857. 1859. 1859. 1859. 1860. 1861. 1863. 1863. 1865. 1867. 1868. 1873. 1874. 1874. 1875, PALAZONTOLOGY OF NEW YORK. Genus LE PT AINA, Daman. 1828. PLATE VIII, FIGS. 12-31; anD PLATE XV a4, FIGS. 40-43. Conchites, Wickens. Nachricht von seltenen Verstein., p. 77, pl. viii, figs. 43, 44. Anomites, WAHLENBERG. Nova Acta Soc. Sci. Upsale, vol. viii, p. 65. Producta, SowErsy. Mineral Conchology, p. 86, pl. cecclix, fig. 3. Producta, Histncur. Acta Acad. Sci. Holm, p. 333. Leptena, Datman. Uppstallning och Beskrifning af de i Sverige funne Terebratuliter; Kong]. Vetenskaps-Academiens Handlingar, fér ar 1827, pp. 94-96, 106, 107, pl. i, figs. 1, 2. Leptena, Kuspen. Die Verstein. der Mark Brandenburg, p. 180. Orthis, von Bucu. Ueber Delthyris oder Spirifer und Orthis, p. 30. Leptena, Hisincer. Lethza Suecica, p. 69, pl. xx, figs. 2, 3. Leptena, FiscHER DE WaALpDHEIM. Oryctogr. du Gouy. de Moscou, p. 143. Leptena, J. pe C. Sowersy. In Murchison’s Silurian System, pp. 623, 636, pl. xii, fig. 2. Orthis, von Etcuwatp. Silurische Schichten-System von Esthland, p. 162. Leptena, Puiurrs. Palsoz. Foss. Cornwall, Devon and West Somerset, p. 51, pl xxiv, fig. 95. Strophomena, Conrav. Fifth Ann, Rept. N. Y.Geological Survey, p. 54. Leptaena, DE Konincx. Descr. Anim. Foss. dans le Terr. Carbonif. Belgique. Strophomena, VaAnuxem. Geology of N. Y.; Rept. Third Dist., pp. 79, 139, fig. 53. Strophomena, Hatt. Geology of N. Y. ; Rept. Fourth District, pp. 77, 104, fig. 52 ; p. 175, fig. 3. Productus?, DE CasretNau. Essai sur le Systéme Silurien de |’Amérique Septentrionale, p. 39, pl. xiii, fig. 7. Orthis, F, Ramer. Das Rhein. Uebergangsgebirge, pp. 85, 90. Leptagonia, McCoy. Synopsis Carb. Foss. Ireland, p. 116. Leptena, pk Vernwuit. Géol. Russie de l'Europe et des Mont. de l’Oural, p. 234, pl. xv, fig. 7. Leptena, King. Annals and Magazine Natural History, vol. xvii, pp. 28, 36. Leptena, Davipson. London Geological Journal, p. 54, pl. xii, figs. 12-16. Leptena, Haut. Paleontology of N. Y., vol. i, p. 108, pl. xxxia, fig. 4. Leptena, Davipson. Bull. Soc. Géol. de France, Ser. 2, vol. v, p. 306, pl. iii, fig. 3. Productus, Davipson. Bull. Soc. Géol. de France, Ser. 2, vol. v, p. 315, pl. iii, tig. 1. Leptena, Kine. Monograph Permian Fossils of England, pp. 81, 104. Leptena, Haut. Paleontology of N. Y., vol. ii, pp. 62, 257, pl. xxi, fig. 8; pl. lili, fig. 6. Strophomena, Bruuincs. Canadian Nat. and Geol., vol. i, p. 59, pl. i, fig. 5. Strophomena, Haut. ‘Tenth Rept. N. Y. State Cab. Nat. Hist., p. 55. Leptena, von Eicuwaup. Lethea Rossica, vol. i, p. 867. Leptena, Haut. Twelfth Rept. N. Y. State Cab. Nat. Hist., p. 82. Strophomena, Haut. Paleontology of N.Y., vol. iii, p. 195, pl. xix, fig. 1; p. 417, pl. xciv, figs. 2, 3. Strophomena, F. Ramer. Silurische Fauna westlichen Tennessee, p. 66, pl. v, fig. 2. Strophomena, Bitunes. Canadian Journal, vol. vi, p. 336, figs. 111, 112. Strophomena, Bitutnas. Geology of Canada, p. 311, fig. 314; p. 367, fig. 373. Strophomena, Binuincs. Proc. Portland Soc. Nat. Hist., p. 107, pl. iii, tig. 1. Leptena, SHALER. Bull. No. 4, Mus. Comp. Zool., p. 65. Strophomena, Haty. Paleontology N.Y., vol. iv, p. 76, pl. xii, fig. 16-18; p. 414, pl. xv, figs.15, 16. Strophomena, MEEK and WortuEN. Geology of Illinois, vol. iii, p. 426, pl. x, fig. 7. Strophomena, MEEK. Paleontology of Ohio, vol. i, p. 75, pl. v, fig. 6. Strophomena, Bruunes. Paleozoic Fossils, vol. ii, p. 27. Strophomena, James. Cincinnati Quart. Jour. Sci., vol. i, p. 333. Strophomena, Miter. Cincinnati Quart. Jour. Sci., vol. ii, p. 55. BRACHIOPODA. 277 1875. Strophomena, Wuite, Geographical and Geological Exploration West 100th Meridian, p. 85, pl. v, fig. 5. 1877. Strophomena, Hatt and Wuirrie.tp. Geol. Expl. 40th Parallel, vol. iv, p. 253, pl. iv, fig. 4. 1877. Plectambonites, Daut. Bull. No. 8, U. S. Nat. Museum, p. 56. 1879. Strophomena, Haut. Twenty-eighth Rept. N.Y. State Mus. Nat. Hist., p. 151, pl. xxii, figs. 4-10. 1882. Strophomena, Hatt. Eleventh Rept. Indiana State Geologist, p. 288, pl. xxii, figs. 4-10. 1883. Strophomena, Haut. Rept. N. Y. State Geologist for 1882, pl. xxxviii, figs. 12-31. 1884. Strophomena, Waucorr. Paleontology Eureka District, p. 118. 1887. Plectambonites, @iutert. Fischer’s Manuel de Conchyliologie ; Brachiopoda, p. 1285. 1889. Strophomena, BgeecHER and CLARKE. Mem. N.Y. State Mus. Nat. Hist., vol. i, No.1, p. 18, pl. ii, figs. 1-13. 1889. Strophomena, NerretrotH. Kentucky Fossil Shells, p. 150, pl. xviii, figs. 1-3. D1aGNosis : “Testa subeequivalvis, equilatera, complanata, margine compresso flexo. “Margo cardinalis transversalis, rectilineus, latissimus, foramine destitutus. “ Valva altera dentibus cardinalibus duobus obtusis.””—Dat.man, op. cit., p. 94. Shells plano-convex when young, concavo-convex at maturity ; convexity normal. Surface covered by conspicuous concentric corrugations or wrinkles over the flatter portions of the valves. Where these cease the surface is more or less abruptly and often rectangularly deflected, forming a conspicuous an- terior slope. The whole exterior is covered with fine, even, radiating, thread- like, tubular striz, which, in well preserved specimens, are crenulated by finer concentric striz. Outline transversely subquadrate or semioval. Hinge-line straight, its length making the greatest diameter of the shell; extremities often subauriculate. Cardinal area narrow, slightly wider on the pedicle-valve, not denticulate. In the pedicle-valve, the delthyrium is covered by a convex deltidium, perforated at the apex by a foramen which is closed at maturity or encroaches upon the apex of the valve. This deltidium is most conspicuously developed in early stages of growth, then having the form of a tube or sheath, which character becomes obliterated as maturity approaches, by the increase in the size of the cardinal process of the opposite valve, and the cal- losity formed about its base. In adult shells the foramen has become enclosed by the substance of the shell, its external opening being an oblique groove in front of the apex of the valve, and its inner aperture appearing in front of the pedicle-scar. Not infrequently the passage is closed at maturity. The teeth are very divergent and quite conspicuous, generally supported by lamellee 278 PALAZONTOLOGY OF NEW YORK. which are continued around the subcircular muscular area of the narrow um- bonal cavity. The muscular scars consist of a narrow median or adductor, enclosed by flabelliform diductors. In the brachial valve the area is linear, the delthyrium is progressively filled by the growth of a callosity, which is often deeply grooved along the center, and sometimes perforated in the line of division between the branches of the cardinal process. The cardinal process consists of two sessile, diverging apophyses which have broad, flat, striated surfaces of attachment, and are extended beyond the hinge-line. The sockets are moderately deep; the crural plates are usually not sharply defined, but are continued in a curving line along the inner surface of the valve, partially embracing a pair of broad, ovate muscular impressions which are marked by arborescent ramifications; recurving and again incury- ing, these ridges partially surround a pair of smaller muscular areas, lying in front of the first. At the inner base of each branch of the cardinal process there arises a low elevation or callosity, which, extending obliquely forward, and uniting in the center, continues as a narrow median ridge dividing the posterior pair of muscular impressions. This ridge sometimes terminates in a point near the base of the first pair of impressions, and the second pair are separated by a low, slender median septum, which sometimes apparently takes its origin at this point, but which is in fact a continuation from the interrupted posterior ridge, and extends for some distance over the pallial region. The muscular area, when its features are most distinctly retained, shows a subdivision into the following scars: (a) A large posterior pair (the posterior adductors), the surface of which is covered with arborescent ridges; the ante- rior portion of each of these scars is smoother than the rest, generally much thickened and often extremely elevated at its outer margins. These may be regarded as accessory elements of the posterior adductors. (b) An anterior pair (anterior adductors), situated close together at about the center of the valve. The position of these is generally well defined but their outline is fre- quently obscure. (c) An elongate, narrow median scar, which is apparently divided for its entire length by a faint ridge. In front of the muscular area there are often a number of short protuberances on each side of the median BRACHIOPODA. 279 septum, and the anterior pair of scars is frequently obliterated by prominent callosities. At the line of geniculation the interior sur- face is elevated into a very prominent, sharp, or abruptly rounded crest. Spiral callosities for the support of the |f brachia, similar to those in Davipsonta and Lepranisca, have been observed by Dr. Davinson. Shell-substance strongly punctate. Fie. 18. Leptena rhomboidalis, showing impressions of spiral arms. After DAVIDSON. Type, Leptena rugosa, Dalman = Producta rugosa, His- inger—=Conchites rhomboidalis, Wilckens. Upper Silurian. Opservations. Having already given at some length the reasons for restricting the application of the term StropHomena, Rafinesque, as defined and illustrated by pE Bratnvitis, the genus Leprana, of Daman, will be left to rest upon its first and typical species, Producta rugosa, Hisinger. This is precisely the interpre- tation of the genus followed by most authors from 1850 to 1860 Prof. Kine, in the Annals and Magazine of Natural History, 1846, and in his Monograph of the Permian Fossils of England, 1850, proposed restricting the genus more narrowly than heretofore, including only “such shells as L. analoga, Phill., L. semiovalis, McCoy, L. plicotis, McCoy, L. nodulosa, Phill., and L. multirugata, McCoy” (Permian Fossils, p. 104). All these are of the type of L. rhom- boidalis. During the early part of this period StropHomeEna, as already pointed out in the discussion of that genus, was a term of uncertain value. Daman placed under his genus Lepr#na four species, in the following order: L. rugosa, Hisinger, L. depressa, Sowerby, L. euglypha, Dalman, L. transversalis, Wahlenberg. The same author observed that the first two of these had been included by WautenBerG, in 1821, under the name Anomites rhomboidalis, this specific term having been first used by Witcxens, in 1/69. The other two species are not congeneric with L. rhomboidalis. Davinson, however, regarding the first three as proper Strophomenas (1853-1884), decided to take the last species, 1. transversalis, as the type of Leprmna, and it is this use of the term that has become current among paleontologists. Were it necessary, however, to reject the first two of Dauman’s species, the third, L. euglypha, a member of the genus SrropHonetia, Hall, 1879, would have to stand as the type of Lep- 280 PALHHONTOLOGY OF NEW YORK. TENA. In 1844, McCoy, having proposed to apply the term Leprana to species of Propuctus or Cuonertes or both, suggested a new term, Lepraconta, for shells like Producta analoga, Phillips = Leptena rhomboidalis.* There are sufficient reasons for limiting the application of the term Leprana to shells conforming precisely to the structure exhibited by L. rhomboidalis. Dr. Davipson, in his later years, was evidently convinced of the validity of this group.t Whether L. rhomboidalis shall be allowed to include all the forms from Silurian to Carboniferous faunas which have the characters given in the foregoing diagnosis, or whether the numerous specific and varietal names that have been proposed shall be recognized in whole or part will depend upon one’s conception of specific values. At all events the type of internal structure accompanied by the peculiar corrugated and geniculated exterior has proved a very compact and resistant combination, a fact evinced by the mere possibility of a question arising as to the specific identity of the various forms. It is worthy of note that among the American representatives of this type of struc- ture which have been studied, the extreme differentiation of the muscular area as described is even more distinctly exhibited in the forms of the early Car- boniferous than in those of the Silurian and Devonian. Believing that it will serve a good purpose in the taxonomy of these organ- isms to thus restrict the generic term Leprana to this peculiar group of forms, it will become necessary to arrange under another designation the much more abundantly developed “ Strophomenas” of the Silurian, exemplified by Lep- tena alternata of Conrav. These differ essentially from L. rhomboidalis, not in their exterior features alone, but also in their interior characteristics; and there is no name among all those which have been suggested or superceded which is applicable, or can be legitimately used, and therefore it becomes necessary to propose a new generic term. * Dr VERNEUIL, in 1845, proposed a classification of the species then referred to this genus, on the basis of their superficial ornamentation. His conception of the genus is expressed in his own words: ‘* Nous proposons de rendre au genre Leprmna, sa valeur primitive, en y réunissant toutes les coquilles plus ou moins analogues a celles que DALMAN avait ainsi nommées ” (Géologie de la Russie, etc., p. 215). We there- fore find in his list of twenty-three species not only the various types of structure given by Datman, but some others. + See General Summary, p. 379. 1838. 1839. 184¢. 1841. 1842. 1842. 1842. 1843. 1844. 1847. 1852. 1856. 1858. 1859. 1859. 1860. 1862. 1863. 1865. 1868. 1871. 1873. 1874. 1874. 1875. 1881. 1881. 1882. 1883. 1883. 1887. BRACHIOPODA. 281 Genus RAFINESQUINA, Gen. nov. Leprrana and StropHoMena of most authors. PLATE VII, FIGS. 1-11; PLATE IXA, FIGS. 1, 2,4; AnD PLATE XVA, FIGS. 37, 38, 39 (?). Leptena, Conrap. Second Ann. Rept. N. Y. Geological Survey, p. 115. Strophomena, Conrad. Third Ann. Rept. N. Y. Geological Survey, pp. 63, 64. Strophomena, Conrav. Fourth Ann. Rept. N. Y. Geological Survey, p. 201. Strophomena, Conrav. Fifth Ann. Rept. N. Y. Geological Survey, p. 37. Strophomena, Conrad. Jour. Acad. Nat. Sci. Phil., vol. viii, p. 254, pl. xiv, fig. 5; pp. 259, 260. Strophomena, VANUXEM. Geological Rapt. Third Dist. N. Y., p. 46, fig. 2. Strophomena, Emmons. Geol. Rept. Second Dist. N.Y., p. 389, fig. 2; p. 395, fig. 3; p. 403, fig. 3. Orthis, De CAsTELNAU. Essai sur le Systéme Silurien de Amérique septentrionale, pp. 87, 38, pl. xiv, figs. 1, 6. Strophomena, Owen. Geol. Expl. Iowa, Wisconsin, and Illinois, pl. xvi, fig. 8; pl. xvii, fig. 6. Leptena, Hatt. Paleontology of N. Y., vol. i, p. 19, pl. iv (bis), fig. 2; p. 20, pl. iv (bis), fig. 3; p. 102, pl. xxxi, fig. 1, pl. xxxia, fig. 1; pp. 106, 107, pl. xxxiA, figs. 2, 3; p. 109, pl. xxxis, fig. 1; p. 115, pl. xxxis, fig. 8; p. 286, pl. Ixxix, fig. 2. Leptena, Hatt. Paleontology of N. Y., vol. ii, p. 62, pl. xxi, fig. 6. Strophomena, Biuuines. Canadian Nat. and Geol., vol. i, p. 214, figs. 3, 4. Strophomena, RocErs. Geology of Pennsylvania, vol. ii, p. 817, fig. 591; p 818, fig. 600. Strophomena, Haut. Twelfth Rept. N. Y. State Cab. Nat. Hist., p. 70. Strophomena, Biurnes. Canadian Nat. and Geol., vol. iv, p. 4438. Strophomena, Bruutnas. Canadian Nat. and Geol., vol. v, pp. 51-54, fig. 1. Strophomena, Biruines. Paleozoic Fossils, vol. i, pp. 117, 118, fig. 97; pp. 119, 128, fig. 106. Strophomena, Bituines. Canadian Geology, Report of Progress, p. 163, fig. 140; pp. 141, 209, fig. 208. Strophomena, SHALER. Bulletin Mus. Comp. Zoology, No. 4, p. 62. Strophomena, Merk and WortuEeN. Geological Survey of Illinois, vol. iii, p. 335, pl. iv, fig. 11. Strophomena, Davipson. British Silurian Brachiopoda, p. 285, pl. xlii, figs. 20, 21; p. 292, pl. xlii, figs. 1-5 ; pl. xxxix, figs. 22-24; p. 296, pl. xxxvli, figs. 23-26 ; pl. xlii, figs. 6-8; p. 383, pl. xlii, figs. 18, 19; pl. xlvii, figs. 1-4; pp. 310, 311, pl. xlii, fig. 11; pl. xiii, fig. 15; p. 312, pl. xlv, figs. 1-10. Strophomena, MEEK. Paleontology of Ohio, vol. i, pp. 88-91, pl. vii. Strophomena, Mitter. Cincinnati Quart. Jour. Sci., vol. i, p. 13. Strophomena, JAMES. Cincinnati Quart. Jour. Sci., vol i, p. 335. Strophomena, Minter. Cincinnati Quart. Jour. Sci., vol. ii, pp. 51-54. Strophomena, N. H. Wincuett. Ninth Annual Rept. State Geologist of Minnesota, p. 120. Strophomena, Waite. Tenth Ann. Rept. Indiana State Geol., p. 113, pl. i, figs. 6, 7. Strophomena, WHITFIELD. Geology of Wisconsin, vol. iv, p. 261, pl. xii, figs. 15, 16; p. 262, pl. xii, fig. 14. Strophomena, Davipson. British Silurian Brachiopoda, Suppl., p. 193, pl. xvi, figs. 6, 7. Strophomena, Hatt. Report N. Y. State Geologist for 1882, pl. xxxviii, figs. 1-11. Strophomena, SHAteR. Memoirs Kentucky Geol. Survey, p. 4, pls. ii, iii. Dracenosis. Shells normally concavo-convex. Surface ornamented by radi- ating striz, of alternating size, crossed and crenulated by finer concentric strie. Cardinal margins without denticulations. Interior of the pedicle-valve 282 PALAZONTOLOGY OF NEW YORK. with the muscular area not strongly limited; consisting of two broad flabel- late diductor scars enclosing an elongate, more distinctly defined adductor. The faintness of the limitation of this area is in marked contrast to the sharply defined muscular area in the corresponding valve of Leprana. In the brachial valve the cardinal process is more closely sessile than in Leprana, and there is frequently a linear callosity between the branches. The posterior adductor scars have the arborescent markings of Leptena rhomboidalis, and these impres- sions are the only ones well defined, the anterior scars being narrow and rarely retained with distinctness. From the anterior margin of the muscular area radiates a series of irregular furrows and nodose ridges, which are to some ex- tent of vascular origin. Type, Leptena alternata, Conrad. Trenton and Hudson River groups. Fig. 19. Rajfinesquina Jukesi, showing the brachial ridges. After DAVIDSON. Oxsservations. There are some shells, a small number of species however, which combine to some extent the characters of both Leprana and Rartnes- quina. We may instance Leptena deltoidea, Conrad, and Strophomena unicostata, Meek and Worthen, in which there are not only low, concentric corrugations on the exterior, but in the latter species the interior of the brachial valve has more distinctly the impress of Leprmna than of Rarinesquina. There are concentrically wrinkled species in the genera STROPHOMENA, STROPHEODONTA and StTropHONELLA, but that character will prove of little value except for a subsidiary grouping of species. The extravagant development of this feature BRACHIOPODA. 283 in Leptena rhomboidalis, persisting throughout so many successive faunas, forms one of the substantial reasons for the separation of that form from its allies. The leptznoid type of structure attained its most abundant exemplification in the faunas of the Silurian. Leptena rhomboidalis, which appeared in the Trenton and Caradoc has alone carried this type onward through the Upper Silurian, the Devonian and into the Lower Carboniferous. RarinesQuina is represented by a number of species in American faunas, e.g., Leptena fasciata, Hall, of the Chazy; L. alternata, Conrad, L. alternistriata, Hall, L. deltoidea, Con- rad, Strophomena camerata, Conrad, and Leptena incrassata, (Hall) Safford, of the Trenton; 8S. Minnesotensis, N. H. Winchell, S. Kingi, Whitfield, S. nitens, Billings, Leptena alternata, Conrad, Strophomena squamula and S. Ulrich, James, from the Hudson River group. In the Clinton fauna the Leptena obscura, Hall, may belong to this group, and if so is probably its latest representative in our faunas. In the Silurians of Great Britain the best developed representation of these fossils is in the Caradoc fauna (Leptena (Leplagonia) ungula, McCoy, L. deltoidea, Conrad, Strophomena Jukesi, Davidson, S. Holli, Davidson, S. siluriana, Davidson, Orthis expansa, Sow- erby). There are a number of species in the Wenlock which appear to belong to this group, such as Orthis Orbignyi, Leptena Waltoni and Strophomena Hender- soni, Davidson. Fic. 20. Strophomena (Rayinesquina) Jukesi, Dayidson. Atter DAVIDSON. 284 PALAZONTOLOGY OF NEW YORK. Genus STROPHEODONTA, Hat. 1852.* PLATE XIII, FIGS, 1-28; PLATE XIV, FIGS. 1-23; PLATE XV, FIGS. 2-24; anD PLATE XVb, FIGS. 1-9. 1830. 1838. 1839. 1841. 1842. 1842. 1843. 1845. 1846. 1848 1848. 1852. 1852. 1853. 1860. 1860. 1861. 1863. 1863. 1863. 1865. 1865. 1865. 1865. 1866. 1867. 1867. 1868. 1871. Plectambonites, PANDER (partim). Beitr. zur Geognosie des russ. Reich., p. 91, pl. xix, fig. 12. Leptana, Conrap. Second Ann. Rept. N. Y. Geological Survey, pp. 112, 117. Orthis, Sowersy. Murchison’s Silurian System, pl. xiii, fig. 12; pl. xxii, fig. 12. Orthis, Putturrs. Palseoz. Foss. Cornwall, Devon and West Somerset, p. 61, pl. xxv, fig. 103. Strophomena, Conrad. Journ. Acad. Nat. Sci. Phila., vol. viii, pp. 254-259, pl. xiv, figs. 2, 4, 6, ty WO, wal, Wes, al). Strophomena, Vanuxem. Geology of N. Y.; Rept. Third District, p. 174, fig. 1. : Strophomena, Hauu. Geology of N. Y.; Rept. Fourth District, p. 104, fig. 3; p. 171, fig. 4; p- 200, fig. 4; p. 266, figs. 1, 5. Leptena, pe Vurneuw. Géol. Russ. et des Mont. de l’Oural, p. 220, pl. xiv, fig. 1; p. 223, pl. xiv, fig. 2; p. 224, pl. xiv, figs. 3, 4; p. 230, pl. xv. fig. 3. Orthis, McCoy. Synopsis Silurian Fossils Ireland, p. 30. Leptana, Davipson. Bull. Soc. Géol. de France, Ser. 2, vol. v, p. 318, pl. iii, fig. 9. Orthis, Strophomena, Puituires and Saurer. Mem. Geological Surv. United Kingdom, vol. ii, pp- 288, 379. Leptana, Stropheodonta, Hatt. Paleontology of N. Y., vol. ii, pp. 61, 63, pl. xxi, figs. 4, 5, 9; p. 327, pl. Ixxiy, fig. 6. Strophodonta, OwEN. Geol. Surv. Wisconsin, Iowa and Minnesota, pp. 584, 585. WLepteena, Scunur. Beschr. Eifel yorkomm. Brachiopoden, pp. 222-224, pl. xxxix, fig. 5; pl. xli, figs. 1, 3, 6; pl. xlii, figs. 3, 4. Strophomena (Strophodonta), Hatt. Tenth Rept. N. Y. State Cab. Nat. Hist., pp. 52-55, 111, 113-115, 137-145. Strophomena, Roaurs. Geology of Pennsylvania, vol. ii, p. 827, figs. 665, 666. Strophodonta, Hatu. Geol. Sury. Iowa, vol. i, pt. ii, pp. 491-493, 495, 496, pl. iii, figs. 1-3, 5, 6. Strophodonta, Hatt. Paleontology of N.Y., vol. iii, pp. 180-184, 191, 194, 411-415, 482, pl. viii, figs. 2-16; pl. xvi, figs. 1-14; pl. xviii, fig. 1; pl. xxii, fig.1; pl. xcii, figs. 2-4; pl. xciii, figs. 2-4; pl. xciv, figs. 2,3; pl xev, figs. 5-10; pl. xev A, figs. 13-19. Strophodonta, Swattow. Trans. St. Louis Acad. Sci., vol. i, pp. 685-639. Strophodonta, Hatt. Thirteenth Rept. N. Y. State Cab. Nat. Hist., p. 90. Strophomena, Birurnas. Canadian Journal, 2nd Ser., vol. vi, p. 338, fig. 113; p. 340, figs. 116-115 ; pp. 341, 348, 344, 348, 349. Strophomena, Bituwwes. Geology of Canada, p. 467, figs. 374, 375. 377; p. 961, figs. 468, 469. Strophodonta, Haut. Sixteenth Rept. N. Y. State Cab. Nat. Hist., pp. 36, 37. Strophomena, Bituines. Proc. Portland Soc. Nat. Hist., p. 109, pl. iu, fig. 3. Strophomena, Binuines. Paleozoic Fossils, vol. i, pp. 120, 122, figs. 98-101. Leptena, Davivson. British Devonian Brachiopoda, p. 85, pl. xviii, figs. 15-18. Strophomena, WincHELL and Marcy. Memoirs Boston Soe. Nat. Hist., vol. i, p. 92, pl. ii, fig. 9. Strophodonta, Meek. American Journal Science, vol. xl, p. 33. Strophodonta, WINCHELL. Rept. Lower Penin. Michigan, p. 93. Strophodonta, Hatt. ‘Twentieth Rept. N. Y. State Cab. Nat. Hist., p. 369, pl. xiii, fig. 34. Strophodonta, Hatt. Paleontology N.Y., vol. iv, pp. 81-93, 96-111, 113, 114, pls. xi; xii, figs. 1-15; xiii; xiv, fig. 2; xv, figs. 1-14; xvi; xvii; xviii; xix, figs.1-5, 8-19. Strophodonta, Murx. Trans. Chicago Acad. Sci., vol. i, pp. 87, 88, pl. xiii, figs. 6, 7. Strophomena, Davipson. British Silurian Brachiopoda, pp. 286; 307, 309, 315, pl. xli, figs. 1-6 ; pl. xliii, figs 16-20; pl. xlvi, figs. 7-10. * SrropHEoponTA, ‘Gr. oTpopevs, cardo, and odovus, dens.” This term has come into general use with the form StropHoponra, which has a different etymology. It may be well to adhere to the original form of the word as more appropriate in its application to these shells. BRACHIOPODA. 285 1871. "Strophomena, Kayser. Zeitschrift der deutsch. geolog. Gesellschaft, vol. xxiii, pp. 620, 621, 624, 625, 627, 630, pl. xiv, figs. 4, 5. 1872. Strophomena, BARRANDE. Systéme Silurien du Centre de la Bohéme, pl. xl, figs. 10-19; pl. xhi, figs. 6-14, 21-28 ; pl. xliii, figs. 1-5, 17-29; pl. xliv, figs. 1-30. 1873. Strophodonta, Hatt and Wurrrietp. Twenty-third Rept. N. Y. State Cab. Nat. Hist., pp. 236, 239, pl. xi, figs. 8-11. 1873. Strophodonta, Nicuotson. Rept. Paleontology Province of Ontario, pp. 64, 65, 67. 1874. Strophomena, Bruuincs. Paleozoic Fossils, vol. ii, pp. 20, 24, 26-29. 1877. Strophodonta, Hatt and Wurrrietp. King’s Expl. and Sury. Fortieth Parallel, vol. iv, p. 246, : pl. iii, figs. 1-3. 1878. Strophodonta, Catvin. Bulletin No. 3, United States Geological Survey, vol. iv, pp. 727, 728. 1878. Strophodonta, Barrett. American Journal of Science vol. xv, p. 372. 1879. Strophodonta, Hatt. Twenty-eighth Rept. N.Y. State Mus. Nat. Hist., p. 151, pl. xxiii, figs. 9, 10. 1880. Stropkhomena, Dawson. Canadian Naturalist and Geologist, 2nd Ser.. vol. ix, p. 341. 1881. Strophodonta, Wurtz. Tenth Rept. Indiana State Geologist, p. 132, pl. iv, figs. 6; 7. 1881. Strophomena, Davivson. Brachiopoda Budleigh-Salterton Pebble-bed, pp. 348-351, pl. xxxix, figs. 1, 2, 4-11. 1882. Strophodonta, Hatt. Eleventh Ann. Rept. State Geologist Indiana, p. 289, pl. xxiii, figs. 9, 10; pl. xxvii, fig. 18. 1882. Strophodonta, Wurrrietp. Geology of Wisconsin, vol. iv, p. 327, pl. xxv, fig. 18. 1888. Strophodonta, Haut. Ann. Bepts By Y. State Geologist for 1882, pls. xiii (44); xiv (45) ; xv (46), figs. 1-24. 1884. Strophodonta, Watcorr. Paleontology Eureka Dist., pp. 118-122, pls. ii, xi, xiii. 1889. Strophodonta, NerreLrorH. Kentucky Fossil Shells, pp. 142-150. 1889. Strophomena, Barrois. Faune du Caleaire d’Erbray, pp. 63-65, 67, pl. iv, figs. 6, 8-10. Draenosis. Shells normally concavo-convex or subplano-convex. Cardinal area common to the two valves, that of the brachial valve narrower or linear ; smooth or finely striated longitudinally, sometimes showing through the outer laminz of the shell strong, parallel, transverse bars, which project beyond the cardinal margin as short processes, and articulate with a corresponding series of pits in the opposite valve. The earliest species have these denticulations developed only for a short distance on each side of the center, while in the lat- ter faunas they extend the entire length of the hinge-line. In the type-species the delthyrium is usually completely closed by the extension of the shelly laminz of the area, and on the inside by the formation of a callosity between the apophyses of the cardinal process. Sometimes a low, narrow, convex deltidium is present, but in the early species the delthyrium is frequently open. From the normal position of the dental lamelle there extend two diverging, sometimes nearly vertical, ridges of variable strength, bounding the post-lateral portion of the muscular area, which is not limited by a ridge in front. The entire muscular area consists of two broad flabelliform diductor scars, enclosing an oval adductor which is distinctly divided into anterior and posterior ele- 286 PALZHONTOLOGY OF NEW YORK. ments. The foramen, dental plates and teeth are obsolete or obsolescent in the Devonian species.* In the brachial valve the delthyrium is also usually closed; the cardinal apophyses are strongly arched into the umbonal cavity of the opposite valve, their surfaces of attachment being sometimes nearly parallel to the plane of the cardinal area of the brachial valve, and often extending beyond it. Small crural plates are always present, though they could not have been functional at maturity. Muscular arrangement similar to that of Leplena rhomboidalis and Rafinesquina alternata, the posterior scars being more elongate, the anterior pair usually less defined, and all the scars frequently obscured. The anterior muscular fulcra are sometimes developed into very prominent elongate apo- physes. The median septum often becomes elevated into a high crest at the center of the valve. Over the pallial region the interior of both valves is strongly papillose. External surface covered with radiating, sometimes fas- ciculate striae; rarely smooth. Shell-substance fibrous, coarsely punctate. Type, Leplena demissa, Conrad. Hamilton group. OxnseRvATIONS. The distinctive characters of this genus are clearly evident, but notwithstanding its importance, both zoologically and geologically, it has never been accorded general recognition except among American writers. Mr. Bitiines would not admit its validity ; Dr. Davipson barely noticed the term ; Professor Kayser and the German writers generally continue to refer its species to STROPHOMENA (= SrropHomena, Leprana, Rarinesquina, etc.); Dr. GiHLert has adopted it, making it a sub-genus of SrropHomena, Rafinesque (de Blain- ville), while he proposes a new genus, Dovuviniina, which is essentially synony- mous. The genus StRopHEODONTA is a large one, being represented in American faunas by not less than fifty species, and it is emphatically characteristic of the Devonian. It makes its first appearance in the Clinton group, having a sparse representation in the Niagara, but becomes more abundant in the Lower * The obliteration of these parts may be due to the excessive secretion of calcareous matter in the um- bonal region. Where this deposit is less there remains some evidence of these features, as in S. profunda of the Niagara, S. Becki of the Lower Helderberg, and especially in S. magnifica of the Oriskany sandstone, one of the largest species of the genus, in which the short dental lamelle converge and unite at the bottom of the rostral cavity, making a sort of pedicle-pit and leaying the delthyrium open. See Plate XIII, fig. 28. BRACHIOPODA. 287 Helderberg, Oriskany and throughout the Devonian, disappearing with the fauna of the Chemung group. The Stropheodontas comprise two natural subdivisions based on the contour of the shells alone. The typical group is strongly concavo-convex, and to this belong the majority of the species which can be referred to the genus in its widest scope. Subordinate to this group of convex forms is a smaller division, exemplified by S. nacrea, Hall, of the Corniferous and Hamilton faunas, in which the surface is smooth, often nacreous and with a few squamous growth-lines. The entire substance of the shell is strongly punctate, the epidermal impunctate layer, which in other species preserves its usual thickness, seems here reduced to a mere film. The interior of the brachial valve bears three diverging ridges in front of the muscular area, in this respect resembling Leptena rhom- boidalis more than typical Srropuzoponra. Closely allied to the species is Strophomena lepis, Bronn, of the Middle Devonian of the Eifel, Belgium and the Asturias.* It may be found convenient to unite these and an unnamed species from the Corniferous limestone under the term PHOLIDOSTROPHIA. The plano-convex species of StropHEoponta are distinguished from the group of S. demissa by more than contour alone. The characters of the deltidium show the same progressive development as in the concavo-convex Strophe- odontas, the earliest species having the delthyrium sometimes open, sometimes partially closed by a convex plate; while in the Devonian species the deltidium is reduced to a flat, transverse lamina, supported within by the callosity about the cardinal apophyses. In the pedicle-valve are two very strongly pustulose, diverging ridges, bounding the muscular impressions on their lateral margins, while anteriorly these scars are broadly flabelliform and not strongly limited. The central adductors are small, relatively obscure and not divisible.; Should * Dr. GisauErRT associates with S. lepis, Bronn, and S. Narajoana, de Verneuil (=S. lepis, Bronn, teste Kayser), the finely striated species S. clawsa, de Verneuil, and S. Leblanci, Rouault. This group, he says, forms a passage to the family Propverms, in the rudimentary condition or absence of the foramen, the obsolescence of the teeth and sockets, the arrangement of the muscles, and especially, in the existence of reniform impressions (Ann. des Sciences Géologique, vol. xiv, Art. No. 1, p. 63, 1887. See pl. iv, fig. 10). Kayser has observed a similar structure in the Leptena caudata, Schnur, of the Eifel (Zeitschr. der deutsch. geol. Gesellsch., vol. xxi, p. 628). + S. Calvini, Miller, and S. Canace, Hall and Whitfield, are convex shells with the interior characters of this group. Neither their external nor internal features are very positively developed, and these shells are excellent examples of connecting forms. 288 PALHIONTOLOGY OF NEW YORK. it be found desirable or important to recognize the value of the characters above indicated, these forms may be separated under the term Leprosrroputa. As typical representatives of this group, may be taken S. magnifica, Hall, of the Oriskany sandstone, and S. perplana, Conrad, of the Corniferous, Hamilton and Chemung faunas; and of the other American representatives we may cite S. tectilis, Hall, of the Coralline limestone, S. Becki, Hall, of the Lower Helder- berg, S. magniventra, Hall, of the Oriskany, S. Junia, Hall, of the Hamilton, S. Trene, S. Blainvillii and S. Tullia, Billings, from the Lower Devonian of Gaspé. In European faunas the group is represented by Strophomena filosa, (Sowerby) Davidson, of the Wenlock, S. explanata, (Sowerby) Kayser, of the Coblenzian, S.? palma, Kayser, of the Calceola beds, and S. Stein, Kayser, of the Wiedaer- schiefer (Lower Devonian) of the Hartz There is a small number of species, the incipient members of the genus Srropueoponta, in which the delthyrium is open, or but partially covered, as in some of its later forms, the crenulations are confined to a very limited ex- tent on either side of the deltidium, and upon one of these forms, Strophomena Leda, Billings, from the Anticosti group, Professor SHALER has proposed to found* the genus Bracuyprion. To the same group belong the Strophomena Philomela, Billings, from the Pentamerus oblongus beds of Anticosti, and Professor SHater has described two other species : from Anticosti, Brachyprion ventricosum and B. genicula- pre... Brackyprion Leda tum. These features can scarcely be regarded as of apa tee generic value, but the group is an interesting one on account of its being the precursor of the fuller development of those characters on which the genus STROPHEODONTA was originally founded. Dr. Gixtert has proposed the generic term Dovvitttna,; for the species Leptana Dutertrit, Murchison,t evidently not fully apprehending its very close * Bulletin of the Museum of Comparative Zoology, vol. i, p. 63. 1865. + In Fischer’s Manuel de Conchyliologie ; Brachiopodes, p. 1282. 1887. { See pz VerneuiL, Géologie de la Russie, etc., p. 223, pl. xiv, figs. 2a, b,c. Fig. 4 of the same plate represents an interior closely similar to that figured by Giutert, and in the explanation of plate is referred to L. Dutertrii, but on page 224 is regarded as belonging to LZ. asella, de Verneuil.~ In this case the latter BRACHIOPODA. 289 relationship to, or identity with StropHnoponra. In his diagnosis of the genus he describes the shel] as having a crenulated hinge and flat deltidium. In the pedicle-valve are two small teeth connected with diverging ridges which are strongly elevated in front and enclose a transverse muscular area. Beneath the beak are two crests supported by a short median septum; posteriorly these all unite to form a single apophysis grooved in the middle and uniting with the inner surface of the deltidium. The brachial valve has a prominent bifid cardinal process, and a pair of small protuberances repre- senting the crural plates; from the base of the cardinal process extends a median ridge which bifurcates ante- Fic. 22. Brachial valve of Dowvil riorly enclosing a cavity for the insertion of the ante- 4, pusererit After cauuman rior adductors. This division may have some value in bringing into association species hav- ing certain slight variations from the type of structure in Stropheodonta demissa. A few convex species in the later Devonian (S. inequistriata, S. arcuata, S. Cayuta, Hall, and S. variabilis, Calvin*), correspond with the characters described by Dr. Giutert, in having the muscular area of the pedicle-valve deepened and its edges strongly elevated. In the brachial valve the anterior myophores have the character of two diverging crests. The genus Srropuroponta, though more prolific in species than RaFInEsQuina, bears much the same relation to Devonian faunas as the latter does to the Silurian. Its earliest members (Bracuyprion) appeared while Rarinesquina still existed, but the advent of the typical Stropheodontas was preceded by the decline and extinction of the Rafinesquinas. This fact is true not of the Amer- ican Paleozoic alone, though it is here best exemplified on account of the far greater abundance of forms belonging to both groups. species must belong to the same group of shells. Both species occur associated in the Devonian of the Bas- Boulonnais, in France, and the environs of Voroneje, in Russia. * This is a peculiarly variable shell exteriorly, sometimes with the convexity normal, at others with the convexity reversed nearly asin SrRoPHONELLA, and again the valves are at times nearly flat, as in S. per- plana. 290 1828. 1837. 1838. 1839. 1840. 1842. 1843. 1846. 1847. 1852. 1852. 1857. 1858. 1858. 1859. 1860. 1861. 1863. 1868. 1865. 1867. 1868. 1871. 1871. 1874. 1879. 1879. 1882. 1883. 1884. 1889. 1889. PALHMONTOLOGY OF NEW YORK. Genus STROPHONELLA, Hat. 1879. PLATE XII, FIGS. 1-21; anD PLATE XVB, FIG. 10. Leptena, Dauman. Kongl. Vetenskaps-Akadem,. Handlingar, p. 108, pl. i, fig. 3. Leptena, Hisincer. Letheea Suecica, p. 69, pl. xx, fig. 4, Leptena, Conrav. Second Ann. Rept. Paleontological Dept. N. Y., pp. 112, 117. Leptena, Sowersy. Murchison’s Silurian System, p. 622, pl. xii, fig. 1. Orthis, von Bucu. Mem. Soc. Géol. de France, vol. iv, p. 222, pl. xii, fig. 26. Strophomena, Vanuxem. Geology of N. Y.; Rept. Third District, p. 122, fig. 5. Strophomena, Hatt. Geology of N. Y.; Rept. Fourth District, p. 104, fig. 3. Orthis, McCoy. Synopsis Silurian Fossils Iveland, p. 30, pl. iii, fig. 11. Leptena, Davipson. London Geological Journal, vol. i, pp. 56, 57, pl. xii, figs. 1-8. Leptena, Haut. Paleontology of N. Y., vol. ii, p. 259, pl. liii, fig. 7. Lepteena (Strophomena), McCoy. British Paleozoic Fossils, pp. 243, 244. Strophomena (Strophodonta), Haut. Tenth Rept. N. Y. State Cab. Nat. Hist., pp. 49-51, 53, 111, figs. 1, 2. Strophodonta, Haru. Geological Survey of Iowa, vol. i, pt. 2, p. 494, pl. iii, fig. 4. Strophomena, Scumipt. Silur. Format. Estland, Nord-Livl. und Oesel, p. 215. Strophodonta, Haut. Paleontology of N.Y., vol. iii, p. 185-190, 193, 1947, 483, pls. xvi, figs. 13, 14 (2); xviii, fig. 3; xx, figs. 1-3; xxi. figs. 1-9; xxiii, figs. 1-7. Strophomena, F. Rormer. Sil. Fauna westl. Tennessee, p. 66, pl. v, fig. 3. Strophomena, Biuuinas. Canadian Journal, vol. vi, p 345, figs. 119, 120. Strophomena, Bituinas. Proceedings Portland Soc. Nat. Hist., p. 108, pl. ili, fig. 2. Strophomena, Bitunes. Geology of Canada, p. 867, figs. 376, 378. Strophodonta, Merk. American Journal of Science, vol. xl, p. 33. Strophodonta, Hatt. Paleontology of N. Y., vol. iv, pp. 93, 112, pl. xiv, figs. la; pl. xix, figs. 6, 7. Strophomena (Strophodonta), Merk and WorrHeN. Geol. Illinois, vol. iii, p. 374, pl. vii, fig. 10. Strophomena, Kaysur. Zeitschr. der deutsch. geolog. Gesellsch., vol. xxiii, p. 625, pl. xiv, fig. 3. Strophomena, Davipson. British Silurian Brachiopoda, p. 288, pl. xl, figs. 1-5; p. 290, pl. xl, figs. 9-13. Strophomena, Bruunes. Paleozoic Fossils, vol. ii, p. 31, pl. ili, fig. 2. Strophonella, Strophodonta, Hatt. Twenty-eighth Rept. N. Y. State Mus. Nat. Hist., pp. 152, 154, pl. xxii, figs. 1-3; pl. xxiii, figs. 1-8. Strophomena, BARRANDE. Systéme Silurien du Centre de la Bohéme, vol. y, pl. xxxix, figs. 1-8. Strophonella, Strophodonta, Hatt. Eleventh Rept. State Geologist Indiana, pp. 290, 292, pl. xxii, figs. 1-3; pl. xxiii, figs. 1-8. Stropkonella, Hatt. Rept. N. Y. State Geologist for 1882, pl. xii (43). Strophodonta, Waucorr. Paleontology Eureka Dist., p. 121, pl. xiii, fig. 10. Strophonella, BEECHER and CLARK. Mem. N.Y. State Mus., vol.i, No. 1, p. 25, pl. iii, figs. 1-8. Strophodonta, Nerretrotu. Kentucky Fossil Shells, p. 149. Diagnosis. ‘Shells semicircular or semielliptical, concavo-convex, resupi- nate, the ventral valve concave and the dorsal valve convex. Ventral area striated, solid, with or without a central deltidial scar, or rarely a partial foramen, with similar features on the narrow area of the dorsal valve; inner margins of the cardinal areas of each valve crenulate, and from beneath the cen- ster of the ventral area there is often a strong process (frequently bilobed) which extends beyond the cardinal line. Muscular area of the ventral valve strongly BRACHIOPODA. 291 marked, and limited by a prominent border. Dorsal valve with a narrow hinge-area transversely or longitudinally striate or both, and marked in the center by a deltidial scar. Cardinal process double, each division notched or bidentate at the extremity; muscular area quadrangular, occupying a more or less elevated callosity, and a central carina rising from the lower part of this area is sometimes produced into a spiniform process in the center of the eavity.’—Hatt, Twenty-eighth Rept. N. Y. State Mus. Nat. Hist., pp. 153, 154. Type, Strophodonta semifasciata, Hall.* Niagara group. OxsseRvatTions. The shells included in this genus are essentially Stropheo- dontas with the relative convexity of the valves reversed. It is evident from a careful inspection of any well-preserved example of SrRopHoNELLA, as already shown from a study of very young individuals of S. striata, Hall, that in early stages of growth the convexity of the valves is normal, reversion of convexity obtaining with growth. + * Since this is the first-named species in the list it will probably be regarded by students as the ‘‘ type ” of the genus, while in fact the generic description had reference to the better known Lower Helderberg forms, and this name was written first in a list of species given in their geological sequence, and including in addition to S. semifasciata, S. Leavenworthana, S. cavumbona and S. punctulifera (the last two probably identical), of the Lower Helderberg group, S. ampla, of the Upper Helderberg group, S. reversa, and S. celata, of the Chemung group; the interior characters of S. semifasciata were less known than in any of the others, and it was included in the group from its resupinate form and the character of the cardinal area, | deltidium, ete. In S. semifasciata, as in the earlier forms of other generic types, the distinctive generic. features may not be, and usually are not, as fully developed as they become in species of later geological periods. + BrecHeR and CrarKe. Development of some Silurian Brachiopoda, p. 25. Mr. Forrsre has shown that the same conditions prevail in S. patenta, as in S. striata of the Clinton group of Ohio and other localities, and writes as follows: “This shell begins its existence with the ventral valve convex and the dorsal concave. _ Later the ante- rior and lateral margins of the ventral valve become concave or turned up, and that of the dorsal valve conyex or turned down. Since this is likewise true of Strophodonta striata, and only the exterior of these specimens is found, as a rule, these species would be difficult to distinguish, were it not for the fact that neither the convexity of the ventral valve, nor the point of strongest concavity of the dorsal valve, lies ever so near to the cardinal line in S. patenta as in S. striata. In other words, S. patenta remained for a longer time a shell of simple curvature.”—Notes on Clinton Group Fossils, with special reference to Collections from Indiana, Tennessee and Georgia, by Auc. F. Forrsrs. Proceedings of the Boston Society of Natural History, vol. xxiv, pp. 300, 301. 1889. See, also, Strophomena patenta; Geological Survey of Ohio; Paleontology, vol, ii, p. 115. 1875. Whether this species is a SrROPHOMENA or a STROPHONELLA remains to be determined, as we do not yet know the exact character of the hinge. The best specimens obtainable do not furnish conclusive evidence of erenulations along this line, while they do show a broad open delthyrium, with evidence of a small apical callosity, or deltidium. Should this species prove a SrropHomena, it is the last of its race, remarkable in having reverted to a primitive or orthoid condition of deltidial structure. Nevertheless the facts above given are certainly of very great interest as showing the progressive generic development in certain forms of Brachiopoda, and in this case suggests the inquiry as to how far certain strophomenoid characters may have been carried forward into SrROPHONELLA. 292 PALHZONTOLOGY OF NEW YORK. In SrropHoNsLLaA as in StropHEoponTA, the earlier representatives possess some of the generic characters in an incipient condition. Species are not known to occur in faunas earlier than the Clinton, where this group is repre- sented by (2) S. patenta and S. striata. The latter species is continued into the Niagara group, where it is associated with S. semifasciata, at Waldron, Indiana. The genus is represented in Europe by 8S. euglypha and S. funiculata. Strophonella striata, Hall, of the Niagara fauna, has a deltidium highly devel- oped in the immature stages of the shell, a prominent deltidial callus, and a short row of cardinal denticulations; it is, in fact, in these respects a reversed Bracuyprion, bearing precisely the same relation to StROPHONELLA in its fuller development as that group does to Stropunoponta. The species also presents some differences from the later Strophonellas in its internal characters. In the pedicle-valve the muscular area is not enclosed, but its lateral margins are bounded by two curved ridges continued from the dental plates. In the brach- ial valve there is a similar arrangement produced by the continuation of the crural plates, but the muscular impressions are extremely faint, the radial markings of the surface extending quite to the base of the cardinal process. Should it be considered useful to recognize the incipient and progressive features of the species NS. striata, and probably S. patenta, towards a full manifesta- tion of generic characters, and distinguish them from StROPHONELLA in its more mature condition of development, the term AmPHISTROPHIA may prove expressive of their apparent double relation as shown in the young and mature shells. In the other Silurian species of SrropHonstia the deltidium is more or less prominently developed as a convex plate, but in the Devonian these parts assume the character they possess in Stropheodonta demissa. In the species of the Lower Helderberg and Devonian the muscular area of the pedicle-valve is deeply impressed and strongly elevated at the margins, less like that of Stropheodonta demissa than that of the later Stropheodontas. In the Lower Helderberg fauna are the species S. Headleyana, Hall, S. cavumbona, Hall, S. punctulifera, Conrad, S. Leavenworthana, Hall, which possess all the typical features of the genus. Itis probable that Strophomena radiata and S. Conradi, Hall, belong to the same genus, but their interior characters are not fully known. In the Upper Helderberg we BRACHIOPODA. 293 have the single species S. ampla, Hall; in the Hamilton group the genus is not represented, but reappears in the early Chemung faunas in S. celata, S. reversa and S. Aybrida, Hall, the last two occurring both in New York and Iowa. Genus LEPTELLA, Gen. nov. PLATE XVA, FIGS. 12-16. 1862. ZLeptena, Brunes. Paleozoic Fossils, vol. i, pp. 73, 74, figs. 66, a, b, 67, a, b, ¢, p. 219.. 1863. Leptena, Birunes. Geology of Canada, p. 231, figs. 242, 243. By the courtesy of Mr. J. F. Wurrzaves, an opportunity has been afforded of studying the original specimens of the species described by Mr. Briurnes as Leptena sordida, from Limestone No. 2, at Point Lévis. These are in a silicified condition and show very clearly all the essential features of their structure. Though they are small, concavo-convex shells with an external aspect like that of Lepraxa or PLectamponirss, the character of the interior is such as to pre- clude the admission of the species into any of the generic divisions now recog- nized. A new name is therefore proposed for them. Dracyosis. Shells small, normally concavo-convex. Outline semicircular or semielliptical. Hinge-line straight, making the greatest diameter of the shell. Pedicle-valve evenly convex, cardinal area moderately high, delthyrium for most of its extent, covered by a convex plate; teeth inconspicuous and un- supported by lamellz; muscular impressions undetermined. Brachial valve slightly concave ; cardinal area comparatively high; the delthyrium filled by the cardinal process, which, as viewed from behind, is divided by a median groove for its entire height. On the cardinal margin this process is double but less conspicuous than the crural plates, which are arched, and highly elevated above the hinge-line. They are short, terminate abruptly, and enclose deep sockets. The visceral area is flattened or concave, its anterior margin forming a double curve, from which line the surface of the valve is abruptly deflected. This visceral area 1s divided by a broad median ridge and its surface covered with fine, sharp radiating lines which end at the line of deflection. Type, Leptena sordida, Billings. Quebec group. 294 PALAZONTOLOGY OF NEW YORK. The structure of the articulating apparatus is the essential basis of distinc- tion between this fossil and PLecramsonrres, but there is also no trace of the characteristic muscular scars of the latter genus. There can be little doubt that the species Leptena decipiens, Billings, from the same formation and locality, belongs to the genus Lupretza. Without having had access to the original specimens, the figure given by Mr. Briuines of the interior of a brachial valve,* showing the double, erect cardinal process, the strong crural plates and the concave visceral area, seems sufficient to determine this point. Precisely similar features are shown in Davipson’s figures of his species Leptena Llandeilo- ensis,+ from the Upper Llandeilo of Ayrshire, and it may also be included in this genus. The name Lepr#nuopsis was proposed by Haupt, in 1878,¢ but as the work in which it was described has not been accessible, no opinion can be expressed in regard to its value. The term has been used by JagKen,§ who refers to the species Leptenulopsis simplex, Haupt, certain small, smooth, semicircular, slightly convex shells, of the age of the Wenlock shale. This author also observes that Haupr included in this genus a few shells having the general aspect of Chonetes minima, Sowerby; but this, according to Davinson, is a strongly plicated shell, though without evidence of cardinal spines. * Paleozoic Fossils, vol. i, p. 73, fig. 67 c. + See Supplement to British Silurian Brachiopoda, p. 171, pl. xii, figs. 26-29. 1883. *Die Fauna des Graptolithen-Gesteines; Ein Beitrag zur Kenntniss der silurischen Sedimentar Geschiebe der norddeutschen Ebene, von Karl Haupt. Band liv des Neuen Lausitzischen Magazins, Gorlitz, 1878, p. 31. + Ueber das Alter des sogen. Graptolithen-Gesteines mit besonderer Beriicksichtigung der in denselben enthaltenen Graptolithen : Zeitschrift der deutschen geologischen Gesellschaft, vol. xli, p. 695. 1890. BRACHIOPODA. 295 Genus PLECTAMBONITES, Panpzr. 1830. PLATE XV, FIGS. 25-29, 32-36; anD PLATE XVa, FIGS. 34, 35. 1828. Leptena, Datman. Kongl. Vetenskaps Acad. Handling., p. 109, pl. i, fig. 4 (not pp. 106-108). 1830. Plectambonites, PANDER. Beitr. zur Geognosie des russischen Reiches, p. 90, pl. iii, figs. 8, 16; pl. xxviii, fig. 19 (generic figures) ; pl. xix, fig. 1. Leptena, of Davipson, 1853, 1871 ; Zirret, 1880; Giaierr, 1887, and authors generally. 1840. Strophomena, Conrad. Ann. Rept. Geological Survey of N. Y., p. 211. 1842. Strophomena, Emmons. Geclogy of N. Y.; Rept. Second District, p. 394, fig. 105. 1843. Strophomena, Haun. Geology of N. Y.; Rept. Fourth District, p. 104, fig. 4; p. 72, fig. 1. 1847. Leptena, Haut. Paleontology N. Y., vol. i, p. 110, pl. xxxis, fig. Fe p 387, pl. lxxix, fig. 3. 1852. Leptena, Hau. Paleontology of N. Y., vol. ii, p. 59, pl. xxi, fig. 1; p. 256, pl. lili, fig. 5. 1856. Leptena, Birues. Canadian Nat. and Geol., vol. i, p. 41, fig. a p. 188, pl. ii, figs. 14, 15. 1863. ZLeptana, Bruuines. Geology of Canada, p. 163, fig. 139. 1865. Plectambonites, SHALER. Bull. Mus. Comp. Zoology, No. 4, p. 64. 1873. Leptena, MeEK. Geol. Survey of Ohio, vol. i, p. 70, pl. v, fig. 3. 1874. Leptena, James. Cincinnati Quarterly Journal of Science, vol. i, p. 151. 1875. Leptena, Minter. Cincinnati Quarterly Journal of Science, vol. ii, p. 57. 1879. Leptena, Utricu. Journal Cincinnati Soc. Nat. Hist., vol. i, p. 15, pl. vii, fig. 12. 1883. Leptena, Hatt. Ann. Rept. N. Y. State Geologist for 1882, pl. xv (46), figs. 25-29, 34-36. 1885. Leptena, Forrste. Bull. Denison University, vol. i, p. 79, pl. xiii, fig. 5. 1887. Plectambonites, SHALER. Mem. Kentucky Geol. Surv., vol. i, pt. 2. Diacnosis. Shells usually small, normally concavo-convex. Surface cov- ered with very fine strie, often alternating in size. Hinge-line making the greatest width of the shell, the extremities often subauriculate. Cardinal area narrow in both valves, sometimes obscurely crenulated on the margins. Pedicle- valve with a moderately broad delthyrium which is partially closed by a convex plate, but mostly occupied by the cardinal process of the opposite valve. Apical foramen sometimes retained. Teeth prominent and supported by thickened plates, which are continued in broad outward curves for more than half the length of the valve, returning and uniting in the umbonal cavity, thus limiting two linguiform muscular scars, enclosing a more or less clearly defined adductor impression. In the brachial valve, the dental sockets are deep, and often appear to tran- sect the cardinal area. The cardinal process is simple and erect but by its coalescence with the short prominent crural plates, the posterior face appears trilobate. The crural plates end abruptly as in OrtHorHErEs ; becoming thick- ened at about the middle of their length, giving origin to two low ridges or septa, which at first approach each other, and thence continue forward with a 296 PALHZZONTOLOGY OF NEW YORK. slight divergence, thus forming the inner boundaries for two elongate muscular scars, which are less sharply defined on their outer margins. ‘The muscular area is rendered quadripartite by two short transverse or oblique posterior fur- rows. Vascular impressions radial, sometimes digitate. Shell-substance fibrous, sparsely punctate. Type, Plectambonites planissima, Pander. Lower Silurian of Russia. Osservations. In applying the term Piecrampontres to the fossils usually refer- red to the genus Leprana, as interpreted by Mr. Davipson in 1853, there is a sufficient justification in the necessities of the case, and in the rights of pri- ority. In this work the example of many of the earlier writers has been fol- lowed, in applying the term Leprmna to the type of structure expressed in Datmay’s first and typical species, L. rhomboidalis. If the progress of knowledge requires a stricter interpretation of generic values than was prevalent a generation ago, at least no injustice has been done to the FIGS. 23, 24, 25. Plectambonites planissima. After PANDER. founders of these groups. The first two of Datman’s four species of Leprana are synonymous with L. rhomboidalis; the third, L. euglypha, Hisinger, belongs to the genus SrropHonELLA, Hall; the fourth is L. transversalis, Wahlenberg, a well known and widely distributed representative of the genus PLECTAMBONITES, Pander, but which, under the conception of the genus, as rendered current by _ Mr. Davinson, has served as the type of Leprmna. The genus PLEcTAMBONITES was thus defined by its author : “ Die Riickenfliiche ist wieder dreieckig, und wiirde man nach ihrer Gestalt allein sich richten, so miissten die hieher gehorigen Formen unmittelbar auf die Orthamboniten folgen, allein wir miissen zu gleicher Zeit die ganze Gestalt der Muscheln betrachten, und so sehen wir, dass diese, hauptsichlich durch die starke Concavitit der Unterschale, niher an Productus kommen. Die Riickenfliche obgleich sie im Allgemeinen dreieckig, und anfangs ziemlich BRACHIOPODA. 297 horizontal ist, nimmt an Hohe allmihlich ab und geht in eine Linie iitber, wie bei Productus; zu gleicher Zeit veriindert sie ihre Richtung und indem sich der anfangs nach hinten hervorragende Hacken der Oberschale allméhlich nach unten umschligt, endlich ganz unter die Unterschale zu liegen kommt, hat die Rickenlinie eme im Verhiltnisse zu den tbrigen Terebratulen verkehrte Stellung angenommen, so dass die Berihrung der beiden Schalen nach oben, der Hacken nach unten zu stehen kommt. Die Oberfliiche der Plectamboniten ist glatt, mit flachen, diinnen, durch breite Zwischenriiume von einander ge- trennte Lingsstreifen versehen; der Hacken ragt sehr wenig hervor. Obere Schale mehr oder weniger, oft sehr stark convex, die untere sehr concav, und ahmt so sehr die Wolbung der oberen nach, dass zwischen beiden ein dusserst kleiner Zwischenraum wbrig bleibt, ja dass man selbst verleitet werden konnte zu glauben, man habe nur eine einzige Schale vor sich.’’* In this diagnosis given by Panprr the external characters of Leprana, Davidson (not Dalman), are very forcibly described, and although the internal features are not detailed, the generic figure, given on plate ii, figure 8, of the - work cited, shows quite distinctly the peculiar cardinal process, crural plates and conspicuous muscular scars characteristic of the brachial valve of this group. Panper described twelve species of PLectamponttss, the first of which, P. planissima, must be taken as the type of the genus. De VerveviL, in 1845,; recognized these specific terms, combining many of them, though retaining several of the original names. Under Leptena convera, Pander, he included P. planissima, P. crassa, and P. testudinata, and remarks that he would have adopted the specific term planissima had it not been in use for a species of Ortuts.t * «The cardinal area [posterior surface] is again triangular, and judging from its outline alone, the forms belonging to this group must follow directly upon Orthambonites, but we must at the same time take into consideration the entire form of the shell, and thus we see that, mainly from the strong concavity of the lower valve, they approach more closely to Productus. The cardinal area, though in general triangular and at first nearly horizontal, gradually decreases in height and becomes linear, as in Productus; at the same time it changes its direction and the projecting beak of the upper valve, which at first is inclined backward, becomes gradually incurved and finally comes to lie wholly beneath the lower valve, so that the cardinal line has, in relation to the other Terebratulas, a reversed position, and hence the surface of contact of the valves is directed upward and the beak downward [see figure 40, page 234]. The surface of the Plectambonites is smooth with low, fine radiating lines separated by broad interspaces. The umbo is not very prominent. Upper valve more or less, often strongly convex, the lower very concave, and following so closely the curva- ture of the upper that between them is a space so extremely narrow as to easily lead to the deception that. but a single valve is present.” + Géologie de la Russie et des Montagnes de Oural, pp. 228-232. } “Cette coquille, que M. Kichwald a considérée comme nonvelle, nous parait tellement identique avec le Plectambonites planissima de M. Pander, que nous n’aurions pas hésité 4 luirestituer ce nom, s’il n’avait 298 PALAZZONTOLOGY OF NEW YORK. No author has been in a more favorable position for the study of PANDER’s spe- cies than M. pg Verneuit, and his testimony is of much accessory importance in de- termining the real import of the genus PLecrampontres. That he himself did not adopt the generic term, is due to the fact that he followed the prevailing custom of rendering to a genus the full breadth of meaning given to it by its author. The elongate-lobate muscular scars, and the peculiar structure of the cardi- nal process are features which at once distinguish PLecramBonires from allied genera. The former character is sometimes approached in certain species of Rarinesquina. Species of this genus have probably not appeared earlier than the faunas of the Trenton and Caradoc-Bala.* The genus disappears in the Niagara; P. transversalis being the last survivor represented. It has been quite generally believed that the genus reappeared in the Trias and Jura, but many of these species have already proven to be of a distinct type of structure, and all of them will unquestionably be found to differ essentially from PLEctaMBonttes.y Genus CHRISTIANIA, Gen. nov. PLATE XV, FIGS. 32, 33; AnD PLATE XVA, FIG. 36. 1837. Plectambonites, PANDER. Beitr. zur Geognosie d. russ. Reiches, p. 92, pl. xix, figs. 9, 10. 1840. Orthis, von Etcuwatp. Ueber das Silur. Schicht. Syst. in Estland, p. 148. 1845. Leptena, dE Verneuit. Géol. de la Russ. et des Mont. de l’'Oural, p. 228, pl. xv, fig. 2. 1846. Productus, McCoy. Synopsis Silurian Fossils of Ireland, p. 25, pl. iii, fig. 4. 1853. Leptena, Davinson. Introd. British Fossil Brachiopoda, pl. viii, figs. 184, 185. 1871. ZLeptena, Davivson. British Silurian Brachiopoda, p. 326, pl. xlvii, figs. 7-158. 1883. Leptena, Davinson. British Silurian Brachiopoda, Suppl., p. 168, pl. xii, figs. 17-21. 1883. Leptena, Hart. Rept. N. Y. State Geologist for 1882, Expl. pl. xv (46), figs. 32, 33. Diagnosis. Shells usually longitudinally elongated, sometimes semielliptical in outline ; normally concavo-convex. Surface smooth or covered with fine radiat- été appliqué par M. Eichwald a4 une Orthis de l’Esthonie. Parmi les Plectambonites de M. Pander, il y en a quatre qui ont une extréme ressemblence aux l’espéce dont nous nous occupons. Les Plectambonites planis- sima et crassa sont ceux que nous aurions voulu choisir comme types, mais ces deux noms ayant déja été donnés 4 des Orthis ou a des Atrypa, nous préférons adopter le nom de convexa qui n’a pas encore été em- ployé.” * The species Leptena sordida and L. decipiens, described by Mr. Binityes, from the Lévis formation, prove to be generically distinct, and are discussed under the genus LEPTELLA. + See the more recent determinations by Munyter pE CuHAatmas, Birrner, ZuaMAyeER, and others. The first of these authors has established the genera KoniIncKELLA (type. Leptena liasina, Bouchard) and Cap- sg YE P OMELLA (type, Leptena Moorei, Davidson), for some of the Liassic species. t This name is proposed as an expression of regard for the memory of Dr. CuristiAn HEINRICH PANDER. BRACHIOPODA. 299 ing lines which are crossed by stronger, rather regular concentric plications. In the pedicle-valve the cardinal area is moderately high and the delthyrium in its normal condition probably closed by a convex plate. The teeth are very divergent and from their bases extend the elevated margins of two linguiform muscular scars, traversing the shell for almost its entire length. These scars, which may be regarded as the diductors, enclose two, much shorter, but still elongate adductors. In the brachial valve the cardinal process is bipartite on its anterior face, each of the lobes being grooved behind; the crural plates are very long and divergent, terminating in elevated extremities or crura. The lower moiety of these plates is produced on each side of a strongly elevated muscular ridge, curving slightly inward on the sides, then outward on approach- ing the anterior margin of the valve, each branch recurving and passing back- ward, parallel to the median axis, as far as the base of the cardinal process. The symmetrical spaces thus limited are each divided transversely at about one- third their length from the hinge-line, by a somewhat lower vertical ridge. The four areas thus enclosed represent the posterior and anterior scars of the adductor muscles. Between the inner muscular walls, in the median line, is a low, rounded, longitudinal ridge. Type, Leptena subquadrata, Hall. Lower Helderberg group. Under the foregoing diagnosis it is proposed to include a few peculiar species which have usually been referred to Leprana, of the type of L. transversalis (= Precramsonitss). While they resemble in many features the structure of this group, there are important differences; in the composition of the cardi- nal process; in the arrangement of the muscular scars, and in the surface ornamentation. The most striking of these peculiarities are the great muscular scars bounded by high walls. In the pedicle-valve the outer diductor scars are much more elongated than ever in Prectampontrus, and in the brachial valve the adductors have the quadruplicate arrangement usually seen to the best advantage in species of Ortuts. In Plectambonites transversalis, however, these adductor impressions, though greatly elongated, are nearly parallel to each other, all converging toward, or meeting in the umbonal region. 300 PALAZONTOLOGY OF NEW YORK. There are at least three well known species which are clearly referable to this proposed genus: Leptena subquadrata, Hall,* from Perry county, Tennessee, referred to the age of the Lower Helderberg group; Leptena tenuicincta, McCoy, elaborately described by Mr. Davipson,; from the Upper Llandeilo and the Caradoc series; Plectambonites ovata and P. oblonga, Pander, which are united by ve Verneuitt under the term Leptena oblonga, from the Lower Silurian beds in the vicinity of St. Petersburg. Davipson includes in L. tenuicincta the Leptena enigma of vn VernevIL,§ from the Lower Silurian beds of the Island of Gotland, a shell much less elongated than the typical L. tenuicincta, and whose interior has not been described. Genus LEPT A NISCA, Betcuer. 1890. PLATE XV, FIGS. 30,31; AND PLATE XVa4, FIGS. 19-30. 1859. Leptena, Haut. Paleontology of N. Y., vol. ili, p. 197, pl. xviii, fig. 2, 1883. Leptana? (sub-genus?), Hatt. Rept. N.Y. State Geologist for 1882; Expl. pl. xv (46), figs. 30, 31. 1890. Leptenisca, BeecHER. American Journal of Science, vol. xl, p. 238, pl. ix, figs. 1-9. Diaenosis. “Shell concavo-convex, attached to foreign objects by calcareous cementation of the ventral beak. Valves articulated by the teeth and sockets. Dorsal or socket valve concave; interior with a broad, more or less defined, spiral impression on each side of the median line, making a single volution. Adductor impressions small. Cardinal line [area] narrow, bearing in the center two prominent, bilobed, cardinal processes, separated to admit the vertical septum in the opposite beak. Ventral valve convex, area elongate-triangular, fissure covered with a pedicle-sheath. Cardinal muscular scar supported on, or limited by a vertical septum, on each side of which, in the anterior half, is a small adductor scar. Shell-structure punctate. “Type, Leptena concava, Hall.”* Lower Helderberg group. This interesting genus includes a few species of attached shells having the general form and contour of PiecramsonrtEs, but with a peculiar combination * This species is first mentioned and illustrated in the Report of the N. Y. State Geologist for 1882, explanation of plate xv (46), figs. 32, 33. 1883. + British Silurian Brachiopoda, pp. 326-328, pl. xlvii, figs. 7-18. t Géologie de la Russie, etc., p. 228, pl. xv, fig. 2. : § Bulletin de la Société Géologique de France, 2e Sér., vol. v, p. 340, pl. iv, fig. 6. 1848. | Beecuer. “On Lepranisca, a new;genus of Brachiopod from the Lower Helderberg group” (op. cit.) BRACHIOPODA. 301 of internal characters, the most striking of which are, the strong dental lamellee, prolonged into the interior of the valve as vertical walls, forming the lateral boundary of the muscular impression; the cardinal process, quadrifid on its posterior and bifid on its anterior face; the very large, broad, much elongated spiral brachial ridges, which make something more than a single convolution. It is observed by Mr. Bercuer that these spiral ridges are better comparable to the so-called reniform impressions of the productids than to the hrachial supports and ridges in Konincxina and Davinsonia. Elsewhere will be found quoted the opinion of the late Professor Nrumayr, that the reniform impres- sions in Cuonnres, Propuctus, etc., were produced by the coiled arms of the animal. The presence of a cardinal process like that in Cuonrres and Pro- DUCTELLA seems to sustain the view of the closer relations of Leprmnisca to this rather than any other group of the articulate brachiopoda. “ In regard to the degree of attachment of the pedicle-valve, two additional species, from the same formation, afford some interesting facts. Leptenisca concava has the cica- trix restricted to a very narrow area about the umbo; L. tangens, a smaller species, is usually found adhering to branches and fronds of bryozoa, and the scar is often deep and may cover the umbonal area; while L. adnascens is attached by the entire external surface of the pedicle-valve, generally to shells of other brachiopods, preferably to Orrnts. A young individual of the last species retains the brachial valve, and shows a well defined cardinal area and a prominent arched deltidium. Genus DA VIDSONTIA, Boucnuarp 1849. PLATE XVA, FIGS. 31-33, 1845. Leptena?, pp Vernevit. Géol. Russie et des Mont. de l’Oural, p. 227, pl. xv, fig. 9. 1849. Davidsonia, BoucHarp. Annals des Sciences Naturelles, 3d Ser., vol. xii, p. 92, pl. i, fig. 2. 1852. Davidsonia, pe Kontncx. Mem. de la Société Royale de Liége, vol. vili, p. 149, pl. i, figs. 1-4; : pl. ii, fig. 1. 2 1853. Davidsonia, Davipson. Introd. British Fossil Brachiopoda, p. 110, pl. viii, figs. 186-193. 1853. Davidsonia, Scunur. Paleontographica, vol. iii, p. 219. pl. xxxix, fig. 4. 1855. Davidsonia, pe Kontnck. Mem. de la Société Royale de Liége, vol. x, p. 281. 1858. Davidsonia, Davinson. The Geologist, No. xi, pl. xij, figs. 33, 34. 1865. Davidsonia, Davipson. British Devonian Brachiopoda, p. 74, pl. xi, figs. 18-16; pl. xv, fig. 18. 1871. Davidsonia, QueNstepr. Petrefactenk. Deutschlands, Brachiopoden, p. 689, pl. 1xi, figs. 103-109. 1871. Davidsonia, Kayser. Zeitschr. der deutsch. geolog. Gesellsch., vol. xxiii, p. 632, pl. xii, fig. 9. 302 PALHVONTOLOGY OF NEW YORK. Dracnosts. Shell thick, plano-convex, transversely oval. Surface smooth or with concentric growth-lines, fixed to foreign bodies by the umbonal portion and the greater part of the surface of the pedicie-valve. Hinge-line straight and quite narrow. On the pedicle-valve the delthyrium is covered by a con- vex imperforate plate; the teeth are large, the dental lamelle obscure. The muscular area is comparatively small, lying in the umbonal region, and is sub- divided into two cardinal scars enclosing an elongate adductor. In the pallial region there is a low median septum which separates two conical callosities of the shell, having their apices directed toward the opposite valve. These pro- tuberances are grooved by a spiral furrow which makes five or six volutions, and are frequently crossed by vascular sinuses. In the brachial valve the deltidial covering is convex, embracing the base of the posterior face of the cardinal apophysis. The cardinal process has very much the same structure as in PLectamBonitEs, consisting of a central, short, erect process, to which the crural plates are attached, giving it a trilobate appearance. These plates terminate abruptly at their distal extremities. The muscular area is quadruplicate and of about the same size as in the opposite valve. ‘Two conical depressions in the pallial region correspond to the protuber- ances of the opposite valve. Shell-substance punctate (?). Type, Davidsonia Verneuili, Bouchard. Middle Devonian. Opservations. In 1859, pe Kontnck detected the existence of calcified spiral brachial supports in this genus, which would give it somewhat the character of Arrypa. Dr. Ginuerr has placed the genus with some doubt in the family Kowrcxiniv, with Koninckina, ANOPLOTHECA, KoNINCKELLA, AMPHICLINA, THE- cospira; the last of these genera being similarly attached by the surface of the pedicle-valve, and all of them being spirigerous. Davipsonia occurs in the middle Devonian (Crinoiden-schichten) of the Eifel, and at an essentially equivalent horizon in England, Belgium and Russia. But two species have been described, D. Verneuili, Bouchard, and D. Bouchardiana, de Koninck, the latter being regarded by F. Ropmer and Kayser as identical with the former. The genus is not represented in American faunas, so far as known. 1793. 1820. 1828. 1828. 1834. 1836. 1836. 1837. 1837. 1839. 1841. 1841. 1841. 1842. 1842. 1842. 1843. 1843. 1844. 1844. 1845. 1846. 1847. 1852. 1852. 1852. 1854. 1854. 1855. 1855. 1857. 1857. 1858. 1858. 1858. 1859. 1860. 1860. 1860. 1861. 1861. BRACHIOPODA. 303 Genus CHONET ES, Fiscuer pe Watpuem. 1837. PLATE XVA, FIGS. 11-18; anpD PLATE XVI, FIGS. 1-11, 14, 15, 18-27, 32-36, 39, 41, 43, 44. Pecten. Ure. History of Rutherglen and East Kilbride, p. 317, pl. xvi, figs. 10, 11. Hysterolithes, Terebratulites, ScHLoTHEIM. Die Petrefacktenkunde auf ihr. jetz. Standpunkt. Leptena, von Bucu. Abhandl., Akad. Wissensch. zu Berlin, pp. 53, 70, pl. iii. Orthis, Daman. Kongl. Vetenskaps Akad. Handlingar, p. 111, pl. i, fig 5. Orthis, Leptena, Kujpen. Verstein. Mark Brandenburg, pp. 179, 181. Orthis, Leptena, Goupruss, von Bucu. Abhandl. d. Kénigl, Akad. d. Wissensch. zu Berlin. Spirifera, Patties. Geology of Yorkshire, vol. ii, pl. ii, fig. 6. Chonetes, FISCHER DE WALDHEIM. Oryctographie du Gouy. de Moscou, pt. ii, p. 134, pl. xxvi, figs. 8, 9. Orthis, Histncer. Lethzea Suecica, p. 70, pl. xx, fig. 7. Strophomena, Conrap. Second Ann. Rept. Paleont. Dept. N. Y., p. 64. Orthis, Leptena, Patuutrs. Paleozoic Fossils Cornwall, Devon and West Somerset, p. 138, pl. Lx, fig. 104. Orthis, D’ARCHIAC and DE VERNEUIL. Descr. Foss. Rhenish Provinces, p. 397. Productus, von Bucu. Abhandl. d. Kénigl]. Akad. d. Wissensch. zu Berlin, p. 25. Strophomena, Conrav. Journ. Acad. Nat. Sci. Phila., vol. viii, pp. 253, 257, pl. xiv, figs. 1, 13. Strophomena, VANuUXEM. Geology of N. Y.; Rept. Third District, p. 149. Leptena, Productus, p’'OrziaNy. Voyage dans l’Amérique Méridionale, Paléontologie, p. 49, pl. iv, figs. 10, 11. Leptena, pe Castetnau. Essai sur le Systéme Silurien de Amérique septentrionale, p. 39, pl. xiv, fig. 9. Strophomena, Hatt. Geology of N. Y.; Rept. Fourth District, pp. 78, 171, 175, 180, 222. Leptena, McCoy. Synopsis Carb. Fossils Ireland, p. 27. Delthyris, FAHRENKOHL. Bemerk. iiber einige Foss. d. Moskow und Kaluga Gouy. Chonetes, DE VERNEUIL. Géologie de la Russie et des Mont. de l’Oural, p. 242. Chonetes, Morris and Suarpr. Quarterly Journal Geological Society London, vol. ii, p. 274, pl. x, fig. 14. Chonetes, DE Konincx. Recherches sur les Animaux Fossiles, pp. 192, 200, 204, 206, 215. Chonetes, HALL. Stansbury’s Expl. Great Salt Lake, p. 410, pl. iii, fig. 1. Chonetes, Hatt. Paleontology of N. Y., vol. ii, p. 64, pl. xxi, fig. 10. Chonetes, OwEN. Rept. Geol. Survey Iowa, Wisconsin and Minnesota, p. 583, tab. v, fig. 12. Chonetes, Davipson. Introd. British Fossil Brachiopoda, p. 113. Chonetes, Norwoop and Pratren. Journ. Acad. Nat. Sci., Philadelphia, vol. iii, pp. 24-30, pl. ii, figs. 2, 4-12. Chonetes, SHuMARD. Geology of Missouri, pp. 201, 202, 216, pl. c, fig. 1. Leptena, McCoy. British Paleozoic Fossils, p. 454. Chonetes, Hatt. Tenth Rept. N. Y. State Cab. Nat. Hist., pp. 116, 119, 145-150 Chonetes, SHuMARD. Engelmann’s Rept. Bryan’s Expl. from Ft. Leavenworth to Bryan’s Pass. Chonetes, Stevens. American Journal of Science, vol. xxv, p. 263. Chonetes, MurK and Haypren. Proc. Academy of Natural Sciences, Phila., vol. x, p. 262. Chonetes, Haut. Rept. Geol. Survey of Iowa, vol. i, pt. ii, p. 598, pl. xii, figs. 1, 2. Chonetes, SHuMARD. Trans. St. Louis Acad. Science, vol. i, p. 390. Chonetes, WortHEN. ‘Trans. St. Louis Acad. Science, vol. i, p. 571. Chonetes, Hatt. Canadian Naturalist and Geologist, vol. v, pp. 144, 145. Chonetes, Merk and WortuEn. Proc. Academy of Nat. Sciences, Phila., p. 450. Chonetes, NEWBERRY. Ives’ Rept. Colorado River of the West, p. 128. Chonetes, Biturnas. Canadian Journal Science and Arts, vol. vi, p. 349. 304 1861. 1862. 1862. 1863. 1863. 1864. 1865. 1865. 1866. 1866. 1866. 1867. 1867. 1868. 1868. 1870. 1870. 1871. 1872. 1873. 1873. 1874. 1874. 1874. 1874. 1875. 1876. 1876. 1877. 1878. 1879. 1879. 1879. 1882. 1882. 1882. 1883. 1884. 1884. 1884. 1884. 1885. 1888. 1888. 1889. 1889. PALAZONTOLOGY OF NEW YORK. Chonetes, Davipson. British Carboniferous Brachiopoda, pp. 182-191, pl. xlvi, figs. 3-7; pl. xlvii, figs. 1-7, 12-18, 25, 28. Chonetes, A. Wincuety. Proc. Acad. Nat. Sci. Phila., vol. xiv, pp. 410, 411. Chonetes, Wurrz. Proc. Boston Society Natural History, vol. ix, p. 29. Chonetes, A. Wincue.u.~ Proc. Acad. Nat. Sci., Phila., vol. xv, p. 5. Chonetes, Bituines. Geology of Canada, p. 368. Chonetes, Meek and Hayprey. Paleontology of Upper Missouri, p. 22, pl. i, fig. 5. Chonetes, Davipson. British Devonian Brachiopoda, pp. 94-96, pl. xix, figs. 4-12. Chonetes, A. WincuELt. Proc. Academy of Natural Sciences Phila., p. 116. Chonetes, A. WincHELL. Geological Rept. Lower Peninsula Michigan, p. 92. Chonetes, Gutnttz. Carbon und Dyas, pp. 58, 60, pl. iv, figs. 12-18. Chonetes, Mexk and Wortuen. Geological Survey of Illinois, vol. ii, p. 253, pl. xviii, fig. 8. Chonetes, Haut. Paleontology of N. Y., vol. iv, pp. 115-145, pl. xx, figs. 1-7; pl. xxi, figs. 1-13; pl. xxii, figs. 1-28, 44. Chonetes, Hatt. Twentieth Rept. N.Y. State Cab. Nat. Hist., p 242. Chonetes, Mrek and Worruen. Geological Survey of Illinois, vol. iii, p. 505, pl. xv, fig. 8. Chonetes, MnrK. Trans. Chicago Acad. Sciences, vol. i, p. 93, pl. xili, fig. 2. Chonetes, A. WincuELL. Proc. Amer. Philosophical Society, vol. xii, p. 250. Chonetes, MEEK and WortHEN. Proc. Acad. Nat. Sci. Phila., p. 35. Chonetes, Davipson. British Silurian Brachiopoda, pp. 331-335, pl. xlix, figs. 13-26. Chonetes, Merk. Final Rept. Paleont. Eastern Nebraska, pp. 170, 171, pl. i, fig. 10; pl. iv, figs. 9, 10; pl. vi, fig. 10; pl. viii, figs. 7, 8. Chonetes, Meek and WortuEeN. Geol. Survey of Illinois, vol. v, p. 570, pl. xxv, fig. 11. Chonetes, Nicuotson. Palzeontology Province of Ontario, pp. 74, 75. Chonetes, Ravupun. Bull. Buffalo Soc. Nat. Hist., vol. i, pp. 250-253. Chonetes, Dersy. Bulletin Cornell University, vol. i, pp. 41, 43, pl. vi, figs. 3, 12, 19; pl. viii, figs. 11, 14, 15, 19; pl. ix, figs. 8, 9. Chonetes, Bituinas. Paleozoic Fossils, vol. ii, pp. 15-29. Chonetes, Wuirz. Prelim. Rept. Wheeler’s Surv. west 100th Merid., p. 19. Chonetes, Wuith. Geogr. and Geol. Surv. west 100th Merid., pp. 121-123, pl. ix, figs 6-8. Chonetes, Menk. Stimpson’s Survey Great Basin of Utah, p. 348. Chonetes, Hatt. Document Ed. T'wenty-eighth Rept. N. Y. State Mus. Nat. Hist., pl. xxii, fig. 15. Chonetes, Hatt and Wurrrietp. U.S. Geological Expl. Fortieth Parallel, p. 253, pl. iv, fig. 9. Chonetes, Dawson. Acadian Geology, Third Edition, pp. 595, 596. Chonetes, Hatt. Twenty-eighth Rept. N. Y. State Mus. Nat. Hist., p. 155, pl. xxii, figs. 11-15. Chonetes, Emerson. Geology of Frobisher Bay ; Nourse’s Narr. Hall’s Arctic Expedition. Chonetes, RATHBUN. Proc. Boston Society Natural History, vol. xx, pp. 18-21. Chonetes, Hatt. Eleventh Ann. Rept. State Geologist Indiana, p. 293, pl. xxii, figs. 11-15. Chonetes, WHITFIELD. Geology of Wisconsin, vol. iv, p. 327, pl. xxv, fig. 16. Chonetes, Davipson. British Devonian Brachiopoda, Supplement, pp. 54, 55, pl. iii, figs. 23, 24. Chonetes, Hatt. Rept. N. Y. State Geologist for 1852, plate xvi (47). Chonetes, Hatt. Thirty-fifth Rept. N. Y. State Mus. Nat. Hist., pl. xxii, fig. 8. Chonetes, WAAGEN. Salt-Range Fossils; Brachiopoda, pp. 614-640, pls. Iviii-lxi. Chonetes, Watcorr. Paleontology Eureka Dist., pp. 123-127, pl. ii, figs. 8, 13; pl. xiii,figs. 14, 15. Chonetes, Wuitr. Thirteenth Ann. Rept. State Geologist Indiana, p. 128, pl. xxv, figs. 7, 8. Chonetes, CLARKE. Bull. No. 16, U. 8. Geological Survey, p. 24. Chonetes, Keyns. Proc. Academy of Natural Sciences Phila. (Extract), pp. 7, 8, pl. xii, fig. 3. Chonetes, Herrick. Bull. Denison University, vol. iii, pp. 35-37, pl. i, fig. 45 pl. ii, fig. 21 ; pl. iii, figs. 12, 14, 21; pl. vii, fig. 22; pl, xii, fig. 3. Chonetes, Nerretrota. Kentucky Fossil Shells, pp. 66-68, pl. xvii, figs. 16-19; pl. xviii, figs. 18-20; pl. xxxi, figs. 20, 30. Chonetes, Sturson. ‘Trans. American Philosophical Society, p. 433. BRACHIOPODA. 305 . Diagnosis. Shells semicircular or transverse, usually normally concavo- convex, sometimes plano-convex. MHinge-line straight, making the greatest diameter of the shell. Pedicle-valve with a narrow concave or flat cardinal area; the delthyrium more or less completely covered by a convex imperforate deltidium. The upper margin of the area bears a single row of hollow vertical or divergent spines, which increase in length toward the cardinal angles; these spines are the prolongations of tubes which penetrate obliquely the substance of the shell in the cardinal region, converging toward the apex of the valve till they reach the surface, where they turn at an abrupt angle upward and out- ward and are thence continued as hollow spines. Cardinal teeth strong. A low median ridge, slightly thickened at its posterior extremity, where it is sometimes coalesced with the deltidium, extends forward, dividing the mus- cular region. The muscular scars are usually faint, and consist of flabelliform diductors which partially enclose elongate median adductors. In the brachial valve the cardinal area is very narrow, and without spines. The deltidium is partially developed, resting against the cardinal apophysis. This process is very similar in character to that in PLECTAMBONITES, consisting of a median portion, coalescing at its base with the elongate crural plates. On its posterior face it is divided by a narrow median furrow and two broader lateral grooves, giving it a quadrilobate appearance. The crural plates are slightly divergent from the hinge-line, bounding narrow, elongate sockets. A median ridge separates the quadruplicate muscular impression, and from between the anterior and posterior members of this impression originate two linear brachial ridges, which extend outward, recurving toward the median line at about the middle of the valve, making a reniform curve. Interior surface of both valves strongly papillose in the pallial region. External surface usually covered with radiating strie, rarely smooth or con- centrically rugose. Shell-substance fibrous-punctate. Type, Orthis striatella, Dalman. Upper Silurian. OssERVATIONS. CHONETES is remarkable for the persistence of its characters. From its appearance in the middle Silurian to its disappearance in the Permian, this type of structure has been maintained with few essential modifications. On 306 PALZHONTOLOGY OF NEW YORK. account of this stability in its features it is difficult to establish any satisfactory subdivision of its members, especially since the genus has been left more com- pact by the recent elimination of some of its aberrant forms Der Koninck proposed* a classification of the species into five sections, based upon the nature of the external ornamentation, as follows: I. Concentrice, those with concentric folds or undulations, like C. concentrica. II. Comate, those with more than one hundred smooth radiating striee. III. Striate, those in which the strize are less than one hundred and more than thirty. IV. Plicose, those with less than thirty strie. V. Rugose, those with rugose radiating plications. An additional group was proposed by Mr. Davipson, viz., Leves, to include smooth shells, like C. polita, McCoy, C. glabra, Geinitz, etc.; and Waacen has more recently added another, Grandicostate, for species with very strong and high radiating ribs. Such an arrangement as this is of course quite conven- tional, and can not meet the requirements of an exact classification, though it may still serve a useful purpose in the absence of a better one. Of the first of DE Konincx’s sections, Concentrice, we have no representation in American faunas. The second and third were properly united by Waagen, and will include the great majority of all known species; the Plicose may embrace such forms as C. mucronata and C. lepida, Hall; of the Rugose and Grandicostate, we have no representatives. The Leves are a group characterizing the Carboniferous and Permian, of which we have the species C. glabra, Geinitz,; while C. polita, McCoy, occurs in the Carboniferous throughout Great Britain, and WaaGen has describedt five additional species of this type from the Productus-limestone of India. The genus CHoneres presents many points of structure in common with Piectamponites. ‘This fact is best seen in the usual size and general contour * Monographie des genres Productus et Chonetes. 1847. + The species C. glabra, Geinitz, and C. levis, Keyes, are synonymous; the former having precedence in time must stand, since the C. glabra, Hall, has been shown to be identical with C. lineata, Vanuxem; Pal. N. Y., vol. iv, p. 121. { Salt-Range Fossils, vol. i, pl. iv, pp. 616, et seg. 1884. BRACHIOPODA. 307 of the shell, and in the cardinal area and articulating apophyses, and may be regarded as of some significance in determining the source and point of departure of the productoid stock. (Minterr has demonstrated the existence of reniform or hook-shaped brachial ridges in the genus StropHEoponta (S. Le- blanct) ;* and although a feature of extremely rare occurrence in that group, it should be given full value in its bearing upon the same question. It has been remarked by many observers that in the earlier forms of CHonrrses the reniform ridges are but faintly, if at all, manifest; the more distinctly pro- ductoid characters of the genus becoming pronounced only with the advent of Propuctus.+ The peculiar cardinal tubes, which are continued into spines, sometimes of a length equal to that of the valves, constitute a feature found only in this group of shells, including CHonostropHta and CHoNoPEcTUS, here described for the first time, CuHonetina, Krotow, and CHONETELLA, Waagen. The existence of these passages across the ventral area, opening into the interior of the shell, was first observed by Kryseruine,t and was dis- cussed at length in Volume IV of the Paleontology of New York,{ and more recently by Mr. Jonny Youne, in Davivson’s Appendix to his Supplement on the Brachiopoda.||_ Fine hair-like spines are sparingly scattered over the striz in C. papilionacea, Phillips, of the Carboniferous limestone, and traces of similar | processes have been mentioned by various writers for other species.7 It is probably true in many cases that the supposed bases of the spines are but the coarse punctations of the inner laminz of the shell-substance, exposed by the abrasion of the impunctate outer or epidermal layer. Furthermore, the Chonetes papilionacea is a species whose generic affinities are still debatable. The shell is of immense size, far exceeding that of any other form referred * Annales des Sciences Géologiques, vol. xix, p. 63. + Guert observes “que les modifications du genre CHonetzs ont lieu tout particuligrement a l’époque carbonifére, et que leur tendance dans certaines espéces, 4 de rapprocher de la forme productoide semble coincider avec l’apparition et la développement maximum du genre Propuctus. Les Cuonrres dévoniens, et surtout ceux qui appartiennent 4 l’époque silurienne, présentent des caractéres plus nettement définis et plus facilement reconnaissables.” t Geogn. Beobachtungen auf einer Reise in das Petschora-land, p. 213. 1846. § G G6 a ae p. 117. ss I ee “ce oe “eé p. 981. “cc q See Davipson, Carboniferous Brachiopoda, p. 188, pl. viii, fig. 8b. 1872; WaAaGEn, Salt-Range Fos- sils, genus CHONETES. 308 PALHONTOLOGY OF NEW YORK. to the group, and this fact, taken in connection with its spinous striz, leads to the presumption that the interior, when known, will show some generic varia- tions of more or less importance. The earliest appearance of CuonetEes in American Paleozoic faunas, is in the Clinton group (C. cornuta, Hall); Chonetes undulata, C. tenuistriata, C. Novascotica, Hall, are known in the Niagara fauna. There is an undescribed species in the Lower Helderberg, and at least one other in the Oriskany sandstone of New York, but these are of rare occurrence. Burnes has described from the Lower Devonian (Oriskany horizon) of Gaspé and the Bay of Chaleurs, C. Canadensis and C. Antiopia. In the Devonian the species multiplied rapidly, and then attained their maximum development, both in number and size ; becorhing less conspicuous in the following faunas, as the productoids increased in develop- ment and importance.* Whether the cardinal spines are ever absent in true CHoneTEs is not yet posi- tively determined; they are often obscure, and as often lost from accidental causes, but no satisfactory evidence of their non-existence has been shown in any species that can be strictly referred to Cuonnrus; although Waacen believes that they were probably never developed in one of his species from the Salt-Range. An analogous structure is exhibited by the species Leptena? nucleata, Hall,y a sinall, obscure shell, occurring in great abundance in certain outcrops of the Oriskany sandstone in New York and Illinois, and in the Upper Helderberg chert of Cayuga, Province of Ontario. In contour the shell is concavo-convex, and externally is unlike Cuonetes in having a smooth surface with concentric squamose lines or lamellz of growth, but no radiating strive, and no spines, either on the cardinal margin or over the surface. The delthyrium appears to have been uncovered. On the interior the pedicle-valve has a broad, thick and considerably elevated median septum, which takes its origin at, or just in front of the apex and is continued over about one-third the length of the shell, end- ing quite abruptly. In well preserved internal casts the impressions of the * WaAAGEN observed (1884), when adding to the genus fourteen new species from the Productus lime- stone, that only about sixty species had been previously known, according to Zirren. This estimate is far too low, since just about sixty well defined species have been described from American faunas alone. + Paleontology of New York, vol. iii, p. 419, pl. xciv, figs. 1 a-d. BRACHIOPODA. 309 teeth are moderately developed, and indicate considerable divergence in the dental ridges. A most remarkable feature on these casts, is the presence, on each side of the umbo, of a minute, greatly elongate and gently tapering cone, the base of which is joined to the cast at about two-thirds the distance from the apex to the cardinal angle; and from this point each one is inclined toward the apex of the shell, and terminates in a free extremity. These delicate cones which are so fragile that they are easily lost and rarely preserved, penetrate, but do not transect the cavity originally filled by the substance of the cardinal portion of the valves; they are evidently the casts of a single pair of large and very oblique spine-tubes, which were not continued into spines as in CHonetes, and evidently did not penetrate to the outer surface of the cardi- nal margin. The inner opening of these blind tubes is situated below and in front of the cardinal area, and their obliquity greatly exceeds that observed in the cardi- nal tubes of Cuonetes. The muscular impressions consist of two flabellate diduc- tors, between which lie two elongate, narrow adductors. Over the pallial region the surface is pustulose. In the brachial valve the cardinal process appears to be simply bilobate, the crural plates narrow and obscure. From the base of the cardinal process extend two slightly divergent median ridges which are con-. siderably elevated at the center of the shell and terminate abruptly. These enclose an elongate muscular scar. There are also two lateral ridges curving outward and then inward, enclosing small thickened areas which appear to be of muscular origin, while the ridges themselves have the curvature of, and suggest the ‘‘reniform impressions.” Nearly the entire inner surface of this valve is covered with radiating rows of strong pustules. This curious shell represents a phase of development in the chonetid type not hitherto described and it may be convenient to separate it under the sub-generic name ANopuia.* Illustrations of the only species known to possess these features, Leptena ? nucleata, will be found on Plate XVa, figures 17 and 18, and Plate XX, figures 14-17. * MEEK and Worruey, in describing this species under the name Leptena? nucleata (Paleontology of Illinois, vol. iii, p. 394; 1868), observed that ‘ this curious little shell does not present the form or internal characters of Leprana, and will probably be found to be a new generic type.” 310 PALHZVONTOLOGY OF NEW YORK. Genus CHONETINA, Krotow. 1888. 1884. Chonetella, Krorow (not WaAGcEN). Artinskische Etage, p. 274. 1888. Chonetina, Krorow. Mém. du Comite Géologique, vol. vi, p. 500. A brief description of the characters of this genus* has been given by (Euxer?,} from which it appears that “ CHonerina differs from Cuoneres by its very convex ventral valve, having a profound sinus; the small valve, very concave, follows the curvature of the larger; in the interior of the dorsal valve are tubercles arranged in radiating series which unite to form high, compact lamelle, extending from the beak to the anterior margin ; two of these, more prominent than the rest, limit the surface occupied by the sinus of the larger valve. The type, C. artiensis, Krotow, belongs to the horizon of the Artinskian grit (Permian).” Without actual knowledge of the specimens upon which this separation from CuonetEs has been based, it may be imprudent to express an opinion as to the value of the proposed genus. The American species which are deeply sinused on the pedicle-valve, e.g., Chonetes Verneuiliana and Ch. mesoloba, Norwood and Pratten, show no valid grounds for separation from CHONETES. Genus CHONOSTROPHIA, Gen. nov. PLATE XVB, FIGS. 14-19; AND PLATE XVI, FIGS. 13, 29. 1857. Chonetes, Hatt. Tenth Rept. N. Y. State Cab. Nat. Hist., p. 56. 1859. Chonetes, Hatt. Paleontology of N. Y., vol. iii, p. 418, pl. xciii, figs. la-d, 2c. 1882. Chonetes, WHITFIELD. Annals N. Y. Academy of Science, vol. ii, p. 213. 1883. Chonetes, Hatt. Rept. N. Y. State Geologist for 1882, pl. xvi, figs. 13, 29. Dracnosis. Shell reversed, concavo-convex, the pedicle-valve being slightly convex about the umbo, but becoming broadly concave over the pallial region. Outline and contour strophomenoid ; valves extremely tenuous and compressed ; surface covered with fine, alternating or fasciculate striz. In the pedicle-valve the upper margin of the cardinal area bears a row of hollow spines of the same structure and arrangement as in Cuonreres. The delthyrium is narrow and appears to be more or less completely closed. The teeth are quite strong and * The original descriptions of both genus and species are in the Russian language. + L’Annuaire géologique universel, vol. v, p. 1152. 1889. BRACHIOPODA. 311 rest upon the bottom of the valve; between them arises a low median septum which may be traced from one-third to one-half the length of the valve, divid- ing a subcordate muscular area, the outer margins of which are distinctly elevated. In the brachial valve the crural plates are united to form a bilobed cardinal process. The outer face of this process has not been observed; on the inner surface it 1s not continued into a median septum but ends abruptly. Muscular area very faintly defined in the type-species. Internal surface over the pallial region finely papillose. Shell-substance fibrous, punctate. Type, Chonetes reversa, Whitfield. Corniferous limestone.* Oxsservations. The peculiar species which is taken as the type of this new division occurs in the fauna of the Corniferous limestone, at Delaware, Ohio, and Cayuga, Province of Ontario. Certain of its peculiarities indicated will not permit its strict generic association with CHonstEs, ¢e.g., the reversed con- vexity and surface ornamentation of the valves, and the apparent structure of the cardinal process. In a general sense the relation between CHonosTROPHIA and CuonerEs is the same as that between SrropHONELLA and STROPHEODONTA, STROPHOMENA and RaFINESQuINA ; but, as in these cases, the reversal of the rel- ative convexity of the valves is not the only difference of importance. Chonetes complanata, Hall, of the Oriskany sandstone, a much larger, more transverse form, also with reversed convexity and with more strongly developed flabelli- form muscular areas, may be placed in the same division until its characters shall be more fully determined. In a different facies of the same fauna is an- other, as yet undescribed congeneric species; and Mr. Biuutnes has described* a form from an equivalent horizon at Gaspé, Chonetes Dawsoni. In the shaly limestone of the Lower Helderberg series, there occurs a species described in this volume as Chonostrophia Helderbergia, sp. nov. * The horizon of this species in Ohio is considered by Mr. WuirrieLp (Annals of the New York Academy of Sciences, vol. ii, p. 212; 1882), the equivalent of the Marcellus shales of New York, on account of its association with a few species of the New York fauna. The character of the sediments is, however, alto- gether different, the rocks at Delaware, Ohio, being largely calcareous. They lie at the top of the Cornifer- ous series in that State and are included in this series by Professor Orton, in his First Report of the Third Geological Survey of Ohio, 1890. The association of the species in the Province of Ontario is invariably with characteristic forms of the Corniferous fauna. * Paleozoic Fossils, vol. ii, p. 18. 1874. 312 PALHAONTOLOGY OF NEW YORK. Genus CHONOPECTUS, een. nov. PLATE XVbB, FIGS. 20-23; anD PLATE XVI, FIGS. 17, 31. 1854. Chonetes, Norwoop and Prarren. Journal Acad. Nat. Sci. Phila., vol. ii, p. 25. 1858. Chonetes, Hatt. Geological Survey of Iowa, vol. i, pt. ii, p. 517, pl. vii, fig. 1. 1883. Chonetes, Hatt. Second Ann. Rept. N. Y. State Geologist, pl. xvii, fig. 17. This name is proposed for the species, Chonetes Fischeri, Norwood and Pratten, a large, normally concavo-convex shell, with a sub-semicircular outline; occurring in the oolitic limestone and yellow sandstone of the Burling- ton beds of Iowa. In this species the cardinal margin of the pedicle-valve bears a row of erect spines, as in Cuonntes. The beak is often compressed or distorted in such a manner as to leave a flattened area, which resembles, and probably is .a cicatrix from attachment in early growth. This charac- ter is more prominent in some individuals than in others, and appears to have become consideraby obscured by the later growth of the shell. The surface ornamentation is also peculiar; the shell bearing a double oblique series of concentric lines, which give to the surface the appearance of the engraving on a machine-turned watch case. These lines are wrinkles rather than strie, and are strongest over the umbonal and central region, where traces of them may sometimes be observed on internal casts of the valves. The wrinkles are crossed by a normal series of very fine concentric growth-lines, and beneath these, but not always exposed, are exceedingly fine, crowded, radiating strie, usually very much interrupted in their course from beak to margin, and often flexuous and irregular. Sometimes the surface is entirely free from the double series of concentric wrinkles, and marked only by the fine radiating and con- centric striae. The internal muscular impressions of the species have not been fully deter- mined. Casts of the pedicle-valve show the impression of a short median septum dividing two broad obcordate flabelliform muscular scars, from the outer margin of which sometimes originates a series of irregularly radiating furrows or ridges, which were probably of vascular origin. Impressions of a very nar- row cardinal area and exceedingly small hinge-teeth are also seen on internal casts of this valve. BRACHIOPODA. 315 Genus CHONETELLA, Waacen. 1884. 1884. Chonetella, WAaAcEN. Mem. Geol. Survey of India; Palontologia Indica, Series xiii, vol. i, No. 4, p. 657, pl. Ixxxi, figs. 3-8. Diaenosts. Shell small, normally concavo-convex. Surface rounded, with radial strie; cardinal area narrow; deltidium, cardinal spines and teeth as in Cuonetes. In the pedicle-valve the adductor impressions are elongate, and are partially enclosed by the larger cardinals. The brachial valve has a small trilobed cardinal process, which is continued into a low median septum. The muscular area is quadripartite and very distinct. The brachial ridges are sharply defined and appear to origi- nate near the outer extremities of the posterior adduc- tors, making a broad outward, and a more abrupt inward curve completing one volution. Surface in the pallial region strongly papillose. Fic. 26. Chonetellu nasuta. After WAAGEN. Type, Chonetella nasuta, Waagen. Upper Carboniferous. Osservations. Dr. WaaceEN has proposed this division for a single species from the Productus limestone of India. Aside from the broadly curved brachial — ridges, its characters are so strongly chonetoid as to render its separation from Cuonetss exceedingly difficult.* The author surmises that some small shells figured by Davinson} and regarded by him as varieties of Productus longispinus, from the Carboniferous shales of Lanarkshire, Scotland, belong to the same group. * The trilobed cardinal process is described in its anterior aspect only, and it is quite probable that upon its posterior face it would be found more similar to that of CuonerEs. The crural plates are very obscure, making the process appear free and erect ; but this is also true of some species of CHONETES, e.g., Chonetes coronata, Conrad. + Carboniferous Brachiopoda, pl. xxxv, figs. 18, 19. 314 PALHHONTOLOGY OF NEW YORK. Genus STROPHALOSIA, Kina. 1844. PLATE XVB, FIGS. 24-37; PLATE XVI, FIGS. 12, 16, 30, 38, 42; PLATE XVII, FIGS. 10-15, 50,51; AND PLATE XVIIA, FIGS. 1-9. 1839. Spondylus, Munster. Beitr. zur Petrefactenkunde, Heft. i, p. 43, pl. iv, fig. 3. 1842. Orthis, Geinitz. Neues Jahrbuch fiir Min., ete., p. 578, pl x, figs. 12, 13. 1843. Strophomena, Haut. Geology of N. Y.; Rept. Fourth District, p. 189, fig. 4. 1844. Strophalosia, Kine. Annals and Magazine of Natural History, vol. xiv, p. 313. 1845. Leptenalosia, Kine (MS.). In de Verneuil’s Géol. de Ja Russ., ete., vol. ii, p. 281. 1846. Strophalosia, King. Annals and Magazine of Natural History, vol. xvii, p. 92. 1847. Orthothrix, Getntrz. Bull. Imp. Soc. des Nat. de Moscou, vol. xx, p. 84. 1847. Productus, pw Kontnck. Monographie des genres Productus et Chonetes, pp. 148, 150, pl. xi, fig. 4; pl. xv, figs.*4, 5. 1848. Orthothrizx, Getnirz. Verstein. der deutsch. Zechst.-gebirg., p. 14, pl. v, figs. 27-37; pl. vi, fig. 20. 1850. Strophalosia, Kine. Monogr. Permian Fossils of England, p. 93, pl. xii, figs. 1-33. 1858. Strophalosia, Davipson. Introd. British Fossil Brachiopoda, p. 115. 1855. Leptena, McCoy. British Paleozoic Fossils, p. 457. 1857. Strophalosia, Davinson. British Permian Fossils, p. 38, pl. iil, figs. 1-10, 19-4]. 1857. Productella, Haut. Tenth Rept. N. Y. State Cab. Nat. Hist., p. 171. 1861. Strophalosia, Guinirz. Dyas, p. 93, pls. xvii, figs. 1-19, 21-39 ; xviii, figs. 1-20 ; xix, figs. 2-6, 25. 1863. Strophalosia, A. Wincurety. Proc. Acad. Nat. Sci., Phila., vol. 15, p. 4. 1866. Orania, A. WincuEett. Rept. Lower Peninsula of Michigan, p. 92. 1867. Chonetes, Hatt. Paleontology of N. Y., vol. iv, p. 148, pl. xxii, figs. 29-43. 1867. Productella, Hatt. Paleontology of N. Y., vol. iv, p. 160, pl. xxiii, figs. 12-24. 1868. Aulosteges, Wuire and Sr. Joun. Trans. Chicago Acad. Sci., vol. i, p. 118, fig. 2. 1874. Strophalosia, Dersy. Bull. Cornell University, vol. i, No. 2, p. 45, pls. iii, iv, viii, ix. 1883. Chonetes (Productella, Strophalosia), Haun. Ann. Rept. N. Y. State Geologist for 1882, pl. xvi (47), figs. 12, 16, pl. xvii (48), figs. 10-15, 50, 51. 1884. Productus (Productella), Waucorr. Paleontology Eureka District, p. 131, pl. xiv, fig. 2. 1884. Strophalosia, WAAGEN. Salt-Range Fossils ; Brachiopoda, pp. 640-657, pl. Ixiii, figs. 2-8 ; pl. Ixiv, figs. 1-9; pl. Ixv, figs. 1-9. 1889. Productella (Strophalosia), WuirEAvEs. Contributions Can. Geol., vol. i, p. 112, pl. xvi, figs. 1, 2. Diaenosis. Shells productoid in general form; a cicatrix, usually apparent on the umbo of the pedicle-valve, indicates that they were attached to foreign bodies by the substance of the shell. Both valves have a well defined area and covered delthyrium, these features beimg much the more conspicuous in the pedicle-valve. In this valve the teeth are prominent, but not supported by lamelle; the muscular arrangement is the same as in Propuctus, though the cardinal impressions are relatively larger and more elongate, extending beyond the limits of the central adductors. In the brachial valve the cardinal process is erect, bifid on its anterior, and quadrifid in its posterior face. It is supported on each side by short, arched crural plates, and is continued into a median septum which extends for half BRACHIOPODA. 315 the length of the valve. Muscular impressions small, quadruple, not dendritic, the interior pair being sharply raised. The brachial ridges originate from between the adductor scars, curving gently outward, recurving, at first grad- ually and then abruptly to their anterior limit; then turning suddenly back- ward, and again inward horizontally, meeting the median septum near its anterior extremity. Surface of the pedicle-valve covered with spines, which near the beak are often curved backward, embracing some external object. In some species all the spines of the valve have evidently been at least of accessory importance in effecting its attachment. The surface of the brachial valve may be either spinous, lamellose or smooth. Type, Orthis excavata, Geinitz, = S. Goldfussi, (Minster) Davidson. Permian of Kurope. OpserRVATIONS. The existence of cardinal areas, delthyria, and articulation, the form of the brachial ridges, and the substantial attachment of the shell either in youth or throughout its existence, make an association of characters which serve to readily distinguish this genus from its allies. The genus STROPHALOSIA is not very abundantly represented in species; all the generic characters described are typically developed only in the Permian mem- bers of the group.* In the earlier forms of the Devonian and Lower Car- boniferous, the expression of the shells is often quite distinct from the later species, though not affording any satisfactory basis for separation. The existence of an articular system and of cardinal areas is not sufficient of itself to distinguish StropHatosia from Propuctetta; and it will therefore be neces- sary to base distinctive generic value upon the umbonal attachment of the former. In the mature condition of the Permian species the umbonal cicatrix of the pedicle-valve is often obscure, having become somewhat obliterated, during their probably free condition near, and at maturity. As observed in the diagnosis, the spines in such species are frequently turned backward in such a manner as to leave the impression that they were certainly flexible, and prob- * See WAAGEN, Salt-Range Fossils; Brachiopoda, p. 640. 316 PALAZONTOLOGY OF NEW YORK. ably attached to some extraneous body, a phenomenon which has been noticed in Propucrus (P. complectens and other species). In some of the earlier species of this genus, eg., S. radicans, Winchell, of the Hamilton group, S. scintilla, Beecher, of the Choteau limestone, and S. Keokuk, Beecher, of the Keokuk group, the entire shell is small, and the pedicle-valve attached by almost its entire surface; the spines on these valves are all attached, creeping like root- lets in irregular, flexuose lines over the surface of the host. A Permian form similar to these was described by Professor Kine,* under the name S. parva, which may be the young of some of the larger associated species; but the Hamilton and Lower Carboniferous forms can not, with our present knowledge, be regarded as undeveloped shells. The affinities of SrropHatosta with both CuonetEs and AuLostsaes, serve to make the transition from the chonetoid shells to Propuctus a complete and very easy one. No satisfactory subdivision of the species of StropHatosta has been made. Dr. Waacen described a number of new species from the Productus limestone of India, and proposed a grouping therefor upon the basis of the general form of the shell. It may be suggested that a good basis for a provisional subdivi- sion of the genus can be found in the character of the external surface of the brachial valve. This valve is spiniferous, as in S. excavata, Geinitz, and the majority of the species; Jamellose, or covered with concentric lamellz or varices of growth, as in S. lamellosa, Geinitz; or smooth, as in S. Leplayi, Geinitz, S. plicosa, Waagen, S. radicans, Winchell, ete. In American faunas SrropHauosra is of rare occurrence. The following species only may be safely referred to the genus: Producta truncata, Hall, of the Marcellus and Hamilton faunas; Chonetes muricatus, and Productella hystricula, Hall, of the Chemung group; Crania radicans, Winchell, from the Hamilton group; S. nwmularis, Winchell, of the Marshall group; S. scintilla, Beecher, of the Choteau limestone; S. Keokuk, Beecher, from the Keokuk group, and probably Aulosteges spondyliformis, White and St. John, from the Coal Measures. To these may be added S. Rockfordensis, sp. nov., from the Upper Devonian of Iowa. None of these species, however, show the typical development of the interior found in the Permian forms. * Monograph of the Permian Fossils of England, p. 102, pl. xii, fig. 33. BRACHIOPODA. 317 Mr. Davivson, in his Devonian Brachiopoda,* has referred the Devonian species, Orthis productoides, Murchison, to StropHALOSIA, but it shows no evidence of attachment, and more properly belongs to Propucrsenta. Professor Kine had previously made a similar reference of this species, and included in the same genus Productus subaculeatus, Murchison, an unattached species, subse- quently taken as the type of PropucrTELia. 1823. 1837. 1842. 1846. 1847. 1861. 1862. 1884. Genus DAVIESIELLA, Waacen. 1884. Productus, SowERBy, Mineral Conchology, vol. iv, pp. 31, 329. Leptena, Fiscuer. Oryctogr. du Gouvern. «le Moscou, p. 143, pl. xxii, fig. 1. Producta, p’ArcHtAc and pg Verneuit. Trans. Geol. Soc. London, 2ad Ser., vol. vi, pt. ii, p. 397. Chonetes, DE KEYSERLING. Beob. Reise in das Petschora-land, p. 214, pl. vi, fig. 1. Chonetes, DE Kontncx. Monogr. du Genre Chonetes, p. 189, pl. xix, fig. 1. Chonetes, Davipson. British Carboniferous Brachiopoda, p. 180, pl. xlv,-figs. 1-7. Productus, Davipson. Brit. Carb. Brachiopoda, pp. 275, 277, pl. xlvi, fig. 1; pl. lv, figs. 6-10. Daviesiella, WAaceN. Mem. Geol. Surv. India ; Paleontologia Indica, Ser. xiii, vol.i, No.4, p. 613. Dr. WaAaGEN writes: “T create this genus for the reception of such forms as Productus Llangollensis, Dav., and Prod. comoides, Sow., which are characterized by cardinal teeth and a second pair of adductor impressions in the ventral valve. The other characters are like those of Propuctus. Mountain limestone.”— op. cit. Fie. 27. Productus (Daviesiella) Llangollensis, Davidson. After DAVIDSON. * Page 97. + Permian Fossils, p. 95. 318 PALAJONTOLOGY OF NEW YORK. The two species named are large, ponderous shells, having the cardinal area and teeth conspicuously developed, the external surface covered with fine radiating striae, and devoid of spines. The existence of the secondary muscular scar in the pedicle-valve can hardly be regarded as a distinctive feature, since it is also well defined in some other species of Propuctus. The form and size of the shells, the arrangement of the muscular scars, and their dendritic markings, and the structure of the cardinal process, all show the very close relationship of these species to the typical forms of Propuctus. It will be difficult to find features of intrinsic importance upon which to justify the separation of these fossils from Propvcte.ua, unless it be in the spineless surface; and yet the general form and expression of the shells is so different from what we are accustomed to meet with in that distinctively Devonian genus, that for the sake of homogeneity in the grouping, it may be well to retain for them this desig- nation. Both P. Llangollensis and P.. comoides are from the Welsh Coal Measures, and may be regarded as the final expression of that combination of characters con- stituting PropucTELta in earlier faunas. BRACHIOPODA. 319 Genus-A ULOSTEGES, von Hetmersen. 1847. PLATE XVII, FIGS. 47-49. 1845. Orthis, pz VeRNEuIL. Géol. Russ. d’Europe et des Mont. l’Oural, vol. ii, p. 198, pl. xi, fig. 5. 1847. Aulosteges, von HELMERSEN. Neues Jahrb. fiir Mineral., p. 330. 1847. Aulosteges, von HeLMERSEN. Bull. Acad. Imp. Sci. St. Petersbourg, vol. vi, p. 135, pl. vi, fig. 12. 1850. (%) Strophalosia, Kinc. Monogr. Permian Fossils England, p. 93. 1858. Awlosteges, Davipson. Introd. British Fossil Brachiopoda, p. 116, pl. ix, figs. 212-216. 1848. Aulosteges, SHumarD. ‘Trans. St. Louis Acad. Science, vol. i, p. 292, pl. xi, fig. 5. 1861. Strophalosia, Grwirz. Dyas, Heft i, p. 93. 1862. Aulosteges, Davipson. Quarterly Journal Geological Society, vol. xviii, p. 33, pl. ii, fig. 7. 1863. Aulosteges, DE Koninck. Fossiles paléozoiques de |’Inde, p. 41, pl. xii, fig. 7. 1883. Aulosteges, Hatt. Ann. Rept. N. Y. State Geologist for 1882, pl. (xvii) 48, figs. 47-49. 1884. Aulosteges, WAAGEN. Paleontologia Indica; Salt-Range Fossils, vol. i, pt. iv, p. 661, pl. Ixii, figs. 1-4; pl. Ixili, fig. 1. Diacnosts. Shell productiform in general aspect, somewhat depressed, not attached. On the pedicle-valve the cardinal area is prominently developed, frequently somewhat distorted; the delthyrium is closed by a convex deltidium which is covered with little tubercles or spinules. Cardinal teeth rudimentary or absent. In the brachial valve the cardinal area is linear, the cardinal process large, quadrifid; its base being surrounded by a strong deltidial callosity. Bra- chial ridges extending nearly to the anterior margin and abruptly incurving. Otherwise the interior impressions are as in Propuctus. Surface of both valves thickly set with spines. Type, Aulosteges variabilis, von Helmersen,= Orthis Wangenheimi, de Verneuil. Permian of Russia. Oxsservations. It was early observed by Kina that AvuLosteces formed a connecting link between StropHatosta and Propuctus. The constant presence of the cardinal area and the usual absence of the hinge-teeth, show the correct- ness of this observation as far as it bears upon the structure of these genera. AvLostEcEs is chiefly if not wholly of Permian age, and it may perhaps be better to regard it as a descendant or offshoot from SrropHatosia ; showing the obso- lescence of teeth, which is the tendency toward the prevailing brachiopod type of that and the preceding fauna. The specific representation of AULOSTEGES is quite meager. The original species, A. Wangenheimi, de Verneuil (which, according to Kine, Davinson and others, is identical with, and therefore has 320 PALZZONTOLOGY OF NEW YORK. priority over von Hetmersen’s A. variabilis), is from the Permian of northern Russia. Davipson recognized no species in the British formations, though Krne, in 1856,* considered his Productus umbonillatus (= P. latirostratus, Howse) an Autosteces. Davipson described A. Dalhousii, and Waacen A. Medlicottianus, from the Permian of the Salt-Range of India. In America but two species have been referred to this genus, namely, A. Guadalupensis, G. C. Shumard, from the Guadalupe Mountains of Texas, a very imperfect shell, insufficiently illus- trated, but showing a high cardinal area; and A. spondyliformis, White and St. John, from the Upper Carboniferous beds of Iowa; a form which it would be difficult to separate from SrropHaLosta on the basis of the features given in the original description and figures. Mr. R. Erueripes, Jr., in discussing “ Adherent Carboniferous Productide,’’+ has figured (figs. 2-4) and described a shell which he regards as CHoneTEs, adherent by its spines (figs. 2, 8) and the outer surface of the pedicle-valve to foreign objects. This discussion is one of great interest and will be referred to at greater length in regard to some important points established in this and a previous paper on the same subject, by Mr. Ernertpez. There is some room for doubt, however, whether these shells should be regarded as belonging to the genus Cuonetes. The individual represented in figure 4 of his work, a pedicle- valve with area and delthyrium, attached by its outer face, and covered with spines creeping over the surface of the host, can hardly be anything but a Srropuaosta of the type of S. radicans, S. Keokuk and S. scintilla. The subject of the other figures, a shell in which one of the cardinal spines encircles a spine of Propuctus, is quite imperfect but has a more decided chonetiform ex- pression. It will be interesting to learn more of this peculiar form. * Annals and Magazine of Natural History. t Quarterly Journal Geological Society, vol. xxxiv, p. 498. 1878. 1778. 1780. 1785. 1789-92. 1793. 1801. 1809. 1811. 1812-14. 1826. 1826-33. 1828. 1829. 183). 1831. 1835. 1836. 1836. 1837. 1838. 1840. 1840. 1841. 1841. 1842. 1844. 1844. 1845. 1845. 1847. 1851. 1852. 1852. 1853. 1854. 1855. 1855. 1855. 1856. 1857. 1857. BRACHIOPODA. 321 Genus PRODUCTUS, Sowersy. 1812. PLATE XVIIA, FIGS. 13-24; PLATE XVIII, FIGS. 6-19; anp PLATE XIX, FIGS. 1-23. Anomia, Da Costa. British Conchology. Gryphites, Watcn. Beitr. zur Geschichte der Gryphiten. Anomia, Pyxis, CHEMNITZ. Neues Systemat. Konchylien-Kabinet, vols. vii, viii. Arca, BRuGuirRE. Hist. Naturelle des Vers testacés. Anomia, Urn. History Rutherglen and East Kilbride, p. 314. Tridacna, LAMARcK. Animaux sans Vertébres. Anomites, Martin. Petrefacta Derbiensia, pls. xv, xvi, xxii, xxxii, xxxiii, xxxvi, xxxvii. Trigonia, PaRKINSoN. Organic Remains, vol. iii, pl. xii, fig. 11. Productus, SowERBY. Mineral Conchology. Protonia, Linck. Handb. d. physikal. Erdbeschreib. Leptena, Goupruss. Petrefacta Germaniz. Leptena, Datman. Uppstalln. och Beskrifn. Sver. funne Terebrat. Terebratula, Rang. Manuel de Vhist. natur. des Mollusques, ete. Mytilus, Fiscuer. Oryctogr. du Gouy. de Moscou, p. 181, pl. xix, fig. 4. Arbusculites, Murray. Acce’t of A. argentea from Carb. limest. Productus, Conrad. Trans. Geol. Soc. Penna., vol. i, p. 268, pl. xii, fig. 5. Productus, Morton. American Journ. Sci. and Arts, p. 153, pl. ii, fig. 2; pl. xxxix, figs. 38, 39. Producta, Pinna, Puiturrs. Geology of Yorkshire, vol. ii. Leptena, Fiscuer. Oryctogr. du Gouy. de Moscou, p. 144, pl. xxi. Productus, SHepARD. Am. Journ. Sci. and Arts, vol. xxxiy, p. 153. Lima, Yon Bucu. Karsten’s Archiv. fiir Mineral. Geogn. ete., p. 60. Pecten, Etcuwatp. Bull. scientif. de Acad. de St. Petersbourg, vol. vii, p. 86. Clavagella, Gotpruss. Petrefacta Germaniz, vol. ii, p. 285, pl. elx, fig. 17. Leptena, J. pe C. Sowersy. Mineral Conchology, vol. vii, pl. 615. Productus, D’OrBIaNY. Voyage dans l’Amerique Meridionale Paleontology, pp. 51-55, pl. iii, figs. 24-26, pl. iv, figs. 1-9, 12, 13, pl. v, figs. 4-10. Lepteéna, McCoy. Synopsis Charact. Carbon. Limest. Ireland, pl. xix, fig. 12. Strophomena, Pottrz and Micuaup. Galerie des Mollusques de Douai, vol. ii, pl. xlii, fig. 5. Productus, DE Verneuit. Geol. de la Russie et des Mont. de ’Oural, p. 246. Productus, DE VerneviL. Travels in North America, vol. ii, p. 221. Productus, pw Kontncx. Recherches sur les Animaux fossiles; Monogr. du genre Productus. Lepteéna (partim), pp Konincx. Descr. des Animaux. Foss. du Terrain Carb. de Belgique. Productus, Owen. Geol: Sury. Wisconsin, Iowa and Minn., pp. 103, 136, 584, pl. v, figs. 1, 3. Productus, Hat. Stansbury’s Expl. Great Salt Lake Region, p. 412, pl. iii, figs. 3, 5, 6. Productus, SHumARD. “Marcy and McClellan’s Expl. Red River of Louisiana, p. 201, pl. i, fig. 5; pl. ii, fig. 1. Productus, Norwoop & Pratren. Journ. Acad. Nat. Sci. Phila., vol. iii, pp. 6-20, pl. i, figs. 1-3, 5, 6, 8-11; pl. ii, fig. 1. Producta, McCoy. British Paleozoic Fossils, p. 473. Productus of authors generally. Productus, Scutet. Rept. Expls. and Surys. from the Mississippi River to the Pacific Ocean, pl. i, fig. 3; pl. ii, figs. 4, 5. Productus, SHumarD. Geol. Rept. Missouri, pp. 201, 216, pl. c, fig. 10. Productus, Hatt. Rept. Expls. and Surys. from Miss. River to Pacific Ocean, vol. iii, p. 103, pl. ii, figs. 16, 17. Productus, Provr. Trans. St. Louis Acad. Science, vol. i, p. 43, pl. ii, figs. 1-16. Productus, Haut. Tenth Rept. N. Y. State Cab. Nat. Hist., p. 180. 322 1858. 1858. 1858. 1858. 1858. 1858. 1859. 1860. 1860. 1860. 1860. 1860. 1860. 1861. 1861. 1861. 1862. 1863. 1863. 1864. 1865. 1866. 1866. 1867. 1867. 1868. 1868. 1870. 1871. 1873. 1873. 1874. 1875. 1875. 1876. 1876. 1876. 1877. 1877. 1878. 1880. 1881. PALHIONTOLOGY OF NEW YORK. Productus, Hatt. Geol. Survey Iowa, vol. i, part 2, pp. 635-639, 674, 675, 712, pl. xii, fig. 3; pl. xix, figs. 1-4; pl. xxiv, figs. 1-3; pl. xxviii, figs. 3-4. Productus, Haut. Trans. Albany Inst., vol. iv, pp. 12, 13. Productus, Swattow. ‘Trans. St. Louis Acad. Sci., vol i, pp. 181, 182, 215-217. Productus, Suumarp. Trans. St. Louis Acad. Sci., vol. i, pp. 290-292, pl. xi, fig. §. Productus, Rogers. Geol. Penna, vol. ii, part 2, p. 833. Productus, Marcov. Geology North America, pp. 45-48, pl. v, figs. 3-6; pl. vi, figs. 1, 3-7, 12. Productus, Meek and Haypen. Proc. Acad. Nat. Sci. Phila., pp. 25, 26. Productus, Murex. Proc. Acad. Nat. Sci. Phila., vol. xii, p. 309. Productus, Merx and Wortuen. Ibidem, pp. 450, 451. Productus, Wortuen. Trans. St. Louis Acad. Sci., vol. i, p. 570. Productus, Waite. Journ. Boston Soc. Nat. Hist., p. 230. Productus, Swattow. ‘Trans. St. Louis Acad. Sci., vol. i, pp. 640, 641. Productus, McCuEsney. Descrip. New Species Palzoz. Foss., pp. 34-40. Productus, SALTER. Quart. Jour. Geol. Soc. Lond., vol. xvii, p. 64. Productus, NEWBERRY. Ives’ Rept. Expl. Colorado River of the West, pp. 121-125, pl. i, fig. 7; pl. ii, figs. 1-10. Productus, Meex & Wortuen. Proc. Acad. Nat. Sci. Phila., p. 142. Productus, Wuitz. Proc. Bost. Soc. Nat. Hist., vol. ix, p. 29. Productus, Swattow. Trans. St. Louis Acad. Sci., vol. ii, pp. 91-94. Producta, A. Wincuetn. Proc. Acad. Nat. Sci. Phila., vol. xv, p. 4. Productus, Merx. Paleontology of California, vol. i, p. 11, pl. ii, fig. 4. Productus, A. W1ncHELL. Proc. Acad. Nat. Sci. Phila., pp. 112-115. Productus, Geritz. Carbon and Dyas in Nebraska, pp. 52, 54, 81, pl. iv, figs. 1-11. Productus, Mnex & WortuHen. Geol. Surv. Illinois, vol. iii, pp. 280, 297, 320, pl. xx, fig. 5; pl. xxiii, tig. 4; pl. xxvi, fig. 4. Productus, Haut. Paleontology New York, vol. iv, p. 146. Productus, Hatt. ‘Twentieth Rept. N. Y. State Cab. Nat. Hist , p. 245. Productus, McCugsnry. Trans. Chicago Acad. Sci., vol. i, pp. 24-27, pl. i, figs. 7-11; pl. vi, fig. 1. Productus, Meex & Wortuen. Geol. Surv. Illinois, vol. iii, p. 528, pl. xx, fig. 7. Producta, A. Wincueit. Proc. American Philos. Soc., vol. xii, p. 249. Productus, Merx. Paleontology Eastern Nebraska, pp. 159-169, pl. i, fig. 14; pl. ii, figs. 2, 5, 6; pl. iv, figs. 5, 6; pl. v, figs. 6, 7, 11, 13; pl. vi, figs. 6, 7; pl. viii, figs. (Oy il), 318}; Productus, WoRTHEN. Geol. Sury. Illinois, vol. vy, p. 569; pl. xxv, fig. 9. Productus, Mkex & Wortuen. Ibidem, p. 569, pl. xxv, figs. 8, 10, 13. Productus, Drrpy. Bull. Cornell Univy., vol. i, pp. 47, 49, 51, 54, 56, 59, pl. i, figs 2, 10-13, 15; pl. ii, figs. 14, 17; pl. iii, figs. 20, 41-44, 46-49; pl. iv, figs. 1-4, 7-i1, 13, 16; pl. vi, figs. 1, 4-7, 9, 17, 18; pl. vii, figs. 5-7, 15, 16; pl. ix, figs. 12, 13. Productus, Mvex. Paleontology Ohio, vol. ii, p. 282, 283, pl. x, figs. 3, 4. Productus, Wuirz. Wheeler’s Geogr. and Geol. Sury. west 100th meridian, pp. $3, 109-116, 120, pl. v, fig. 6; pl. vii, figs. 1, 2; pl. viii, figs. 1-6. Productus, Mrex. Bull. U. 8. Geol. and Geogr. Sury. Terr., vol. ii, p. 354, pl. i, fig. 1. Productus, Dersy. Bull. Mus. Comp. Zool., vol. iii, pp. 280, 281. Productus, NewBerRY. Rept. Macomb’s Expl. Exped. from Santa Fé to junction of Grand and Green Rivers of the Great Colorado of the west. Productus, Hat, & Wuirrietp. U. 8. Geol. Expl. 40th Parallel, vol. iv, pp. 265-268, pl. v, figs. 3-12. Productus, Meex. Ibidem, pp. 64-67, 69, 72-76, pl. vii, figs. 3-8; pl. viii, figs. 2-4. Productus, Dawson. Acadian Geology, third ed., pp. 296, 297. Productus, Wuirn. Proc. U. 8. Nat. Mus., p. 46. Productus, Wuirr. Tenth Ann. Rept. Indiana State Geologist, p. 148, pl. viii, figs. 7, 8. BRACHIOPODA. 323 1882. Productus, WuitFietp. Bull. Amer. Mus. Nat. Hist., vol. i, No. 3, pp. 46, 47, pl. vi, figs. 6-12. 1882. Productus, Wuire. Eleventh Ann. Rept. Indiana State Geol., p. 373, pl. xlii, figs. 1-3. 1883. Productus, Hatt. Twelfth Ann. Rept. Indiana State Geol., pp. 325, 326, pl. xxix, figs. 6, 7. 1883. Productus, Haun. Rept. N. Y. State Geol. for 1882, plates (xviii) 49; (xix) 50. 1883. Productus, Ware. Twelfth Ann. Rept. U. 8. Geol. Sury. Terr., p. 132, pl. xxxvi, fig. 1. 1884. Productus, Wuirx. Thirteenth Ann. Rept. Indiana State Geol., pp. 122-126, pl. xxiv, figs. 1-11 ; pl. xxv, figs. 1-5; pl. xxvi, figs. 1-3; pl. xxvii, figs. 1-3. 1887. Productus, Herrick. Bull. Denison Uniy., vol. ii, pp. 47-49, pl. ii, figs. 25-30. 1888. Productus, Herrick. Ibidem, vol. iii, pp. 31-34, pl. i, figs. 24, 26; pl. iii; figs. 2 vii, figs. 11, 20; pl. x, fig. 6, vol. iv, pp. 19-23, pl. iii, figs. 1 x, figs. 24, 25; pl. xi, figs. 26, 29, 1888. Productus, Keyes. Proc. Acad. Nat. Sci. Phila., Extract, pp. 6, 7. Our knowledge of the generic characters of this group has not greatly pro- gressed during the last forty years. Though with the advance of investigation the specific representation of the genus has become enormous,* the generic value of Propuctus was nearly as well understood, if not so closely restricted, at the date of the elaborate discussions of the genus by pr Verneurn (Géologie de la Russie, etc., 1845), and pe Konincx (Monographie du genre Productus, 1847), as at the present time. The generic divisions which have been since proposed for species then referred to PRropuctus seem to have but limited value or to represent no fundamental variation from the type of the old genus. The fol- lowing diagnosis can not, therefore, vary materially from those given by earlier writers.} Diagnosis. Shell free, concavo-convex, the valves usually produced anteriorly; outline semicircular, sometimes transversely elongate. Pedicle-valve convex, sometimes geniculated, occasionally with a median sinus. Cardinal extremities frequently auriculate. Umbo inflated, with apex incurved. Hinge-line straight, cardinal area and teeth absent or rudimentary. External surface usually with more or less prominent radiating ribs which are crossed, especially in the umbonal region, by concentric lines or wrinkles; rarely smooth or finely striated, often studded with spines varying in size and abundance. These spines are * Dr Kontnck described sixty-one species in his Monograph in 1847, not recognizing the genus STROPHA- Losta, King, 1844, nor indicating the various subdivisions which subsequent writers have erected into genera or subgenera. In MituEr’s North American Geology and Paleontology (1889) eighty species of Propuctus and twenty-seven species of PropucrELLA are given as occurring in the Paleozoic rocks of this continent alone. + WaAaegEn, after his elaborate study of the species of the Propucrus limestone of India (1884), says: “T have nothing new to add to them [the generic characters].” 324 PALHZONTOLOGY OF NEW YORK. frequently scattered irregularly over the surface, generally strongest and dis- posed. with greatest regularity upon the cardinal extremities, and sometimes oc- curring only in this region. ‘They are hollow and appear to have communicated with the interior cavity of the shell. On the interior of the valve is a narrow median ridge, separating the two dendritic impressions of the adductor muscles; outside and in front of these are two broadly flabellate, longitudinally striated scars of the cardinal muscles. In the pallial region are sometimes found traces of spiral cavities, which were occupied by the fleshy arms.* The brachial valve is operculiform, more or less concave or almost flat over the visceral area. Cardinal area, sockets and crural plates absent or rudi- mentary; cardinal process strong, curved or erect, extending far above the hinge-line ; its inner face is divided into two lobes by a longitudinal furrow, and each of these parts is deeply divided at its extremity, giving the process in this aspect a quadrilobed appearance. As viewed from the posterior or outer face it is strongly trilobed, the inner members of the lateral lobes coalescing to form a very prominent apophysis. The process is continued over the interior of the shell as a longitudinal septum, dividing the impressions of the adductor muscles. The latter are strongly dendritic and rarely divisible into anterior and posterior elements. The brachial ridges; take their origin from near the post-lateral margins and nearly enclose a sub-circular, smooth or granulose area. The internal surface of this valve is strongly postulose, and in the pallial region frequently spinous. * See Davipson, British Carboniferous Brachiopoda, pl. xxxvii, fig. lL. 1861. +t Waacen says (Productus-limestone Fossils, p. 611): “‘A passage in Professor Nrumayr’s paper [Neues Jahrbuch fiir Mineralogie, 1883, vol. ii, p. 27], which is of very great importance, I must quote here more in detail. He says, a chief oljection of Davipson’s against the opinion that these ridges form a part of the brachial apparatus is the existence of spiral impressions which are to be found in the ventral valve of some specimens of Propucrus, and which beyond any doubt are impressions of the spirally enrolled arms of the animal. Now, as these impressions show not the slightest accordance with the brachial ridges [reni- form impressions], Mr. Davipson concludes that these latter cannot be taken as belonging to the brachial ap- paratus. ‘I cannot concur,’ says Professor NEuMAyR, ‘in this argument. The greatest number of the now living Brachiopods have arms showing a double curve; and if such were, as is probable, present in Pro- puctus, these features (the ridges in the one and the spiral impressions in the other valve) are in no way difficult to explain; on the contrary they indicate very accurately the direction and the manner in which the arms extended in Propuctus. They run first along the descending, then along the reascending branch of the ridges, were then bent back over the descending branch, and curled in a spiral coil, which caused the impression in the ventral valve. Thus, in their general shape, these arms very nearly agree with those occurring in TEREBRATULA and WALDHEIMIA, though in proportion and direction of the different parts certain differences exist.’ This deduction is of very great systematic importance.” BRACHIOPODA. 325 Shell substance fibrous, strongly punctate. Type, Productus Martini, Sowerby, == Anomites productus, Martin, = Anomites semireticulatus, Martin, —= Productus semireticulatus, Martin. Lower Carboniferous limestone to Coal Measures. OxsseRvations. It is the usage of some systematists to regard the genus Propuctus as a starting point in the classification of the articulate brachiopoda on account of the usual absence of the cardinal area and teeth. These are features which are unquestionably in an obsolescent condition. It is rarely, however, that some trace of them is not discernible, and it has been observed by various writers, that they are sometimes well-defined, and that too in species where they are normally wanting. For example, they may be present in the species Productus semireticulatus and P. Nebrascensis. In these features Propuctus is degenerate, but this degeneracy has apparently not extended to other points of structure, and the genus certainly lacks the simplicity of plan in its structure so apparent in Ortuis. Its late appearance in the Paleozoic and its close kinship to the Cuongrss-stock is evidence of its derivation from that source. The earliest phase of the productoid type, which is abundantly developed in the Devonian, and which has been distinguished by the name of PropucteE.a, retains the articulating processes and cardinal area with persist- ence throughout the period immediately preceding the appearance of normal Propuctus. These features are, however, always more or less obscure, and manifestly approaching desuetude. Leaving for the present the consideration of this and the other generic or subgeneric divisions, which have been taken from Propuctus, we have, in this genus, to deal with a very homogeneous group of fossils. A grouping of the species of Propuctus was proposed by pE VERNEUIL in 1845,* and this was amended and somewhat amplified by pr Konincx in 1847.+ Dr. Waacen, in his magnificent treatise on the Producti of the Salt-Range, is the latest writer who has discussed the genus at length, and has adopted this classification with some modifications and additions; it is evident that no * Géologie de la Russie, p. 253. + Monographie du genre Productus, p. 29. 326 PALHIONTOLOGY OF NEW YORK. better means for the arrangement and simplification of this group can now be offered. Some of the divisions made by the French authors must be aban- doned, since the forms on which they were founded have been advanced to a generic or subgeneric designation ; namely, the group Laves, de Koninck, which included P. Leonhardi = Koninckina ; the Proboscidei, de Koninck, for shells like P. proboscideus, de Verneuil, a group for which (inierr has proposed the sub- generic term ProposcipeLia; and the Caperati, de Verneuil, a group of Devo- nian and Carboniferous forms essentially equivalent to PropuctELLaA. WaAasGEN has proposed to divide the group Sfriati, de Verneuil, into the Lineati and Trregulares. We have then the following arrangement, with citations of American repre- sentatives of each group: I. Lineati, Waagen. Surface covered with fine radiating costze which are rarely spinous and are not crossed by concentric plications or wrinkles. These shells are greatly produced and sometimes the anterior margins of the valves are modified by the development of a fold or sinus (P. Americanus, Swallow, = ? P. equiradiata, Shumard). The shells were very fragile and have usually been subjected to much distortion in fossilization. Examples : P. Cora, @ Orbigny. P. Americanus, Swallow. P. Prattenanus, Norwood. P. equicostatus, Shumard. P. levicostus, White. P. pileiformis, Newberry. P. ovatus, Hall. P. nodosus, Newberry. Il. Irregulares, Waagen. LHlongate shells very narrow at the beak, mytili- form in outline; mode of growth quite irregular. Surface as in the Lineati ; spines grouped almost wholly about the cardinal line. We are not aware that any member of this group has been recognized in America. The best known species is P. striatus, Fischer, a widely distributed form in the Carboniferous limestone of Europe. Waacen has described the species P. compressus and P. mytiloides, from the Permo-Carboniferous of the Salt-Range. III. Semireticulati, de Verneuil. The longitudinal ribs are sparsely spinous ; surface of the visceral disc covered with concentric wrinkles. This group includes the greater number of North American species, but it BRACHIOPODA., 327 is to be observed that specific distinctions in the group are established with great difficulty on account of the persistence of the type of structure without essential modification. i Examples: P. semireticulatus, Martin. P. Wortheni, Hall. P. arcuatus, Hall. P. magnus, Meek and Worthen. P. costatus, Sowerby. P. nanus, Meek and Worthen. P. Burlingtonensis, Hall. P. Lasallensis, Worthen. P. Altonensis, Norwood and Pratten. P. tenuicostatus, Hall. P. Chesterensis, Worthen. IV. Spinosi, de Verneuil. Surface strongly tuberculose or spinose; not reticulated. Examples : P. Nebrascensis, Owen. P. scabriculus, Martin. P. asper, McChesney. P. marginicinctus, Prout. V. Fimbriati, de Koninck. Surface without radiate striz or ribs; covered with concentric ridges or plications, bearing rows of small, thickly set spines. Examples : P. punctatus, Martin. P. alternatus, Norwood and Pratten. P. vittatus, Hall. P. symmetricus, McChesney. P. biseriatus, Hall. P. Rogersi, Norwood and Pratten. VI. Horridi,de Verneuil. Surface without radiating or concentric plications ; pedicle-valve with a deep sinus. It is doubtful if any member of this group is known from American faunas. Among European species are: P. horridus, Sowerby. P. opuntia, Waagen. P. Geinitzianus, de Koninck. VII. Mesolobi, de Koninck. Surface without radiating plications, except a prominent median rib. Unknown in this country. Examples in the European Devonian are: P. mesolobus, Phillips. P. Christiani, de Koninck. 328 1840. 1840. 1842. 1842. 1846. 1854. 1857. 1858. 1860. 1861. 1862. 1863. 1865. 1867. 1867. 1868. 1870. 1872. 1874. 1875. 1877. 1879. 1883. 1884. 1888. 1889. PALHZONTOLOGY OF NEW YORK. Genus PRODUCTELLA, Haw. 1847. PLATE XVII, FIGS. 1-9, 16-46. Productus ( partim) of earlier authors. Leptena, J. pe C. SowErBy. Trans. Geol. Society London, vol. v, p. 704, pl. lvi, fig. 5. Productus (partim), Murcuison. Bull. Societé Geol. de France, yol. xi, p. 255. Strophomena, Vanuxem. Geol. N. Y. Rep. Third Dist., p. 179. Strophomena, Conrav. Journ. Acad. Nat. Sci. Phila., vol. viii, p. 256, pl. xiv, fig. 9. Strophalosia (partim), Kine. Ann. and Mag. Nat. Hist., vol. xviii. Productus, Norwoop and Prarren. Jour. Acad. Nat. Sci. Phila., vol. iii, p. 21. Productus, Haut. Tenth Rept. N. Y. State Cab. Nat. Hist., pp. 172-180. Productus, Haut. Geol. Sury. Iowa, vol. i, part 2, pp. 498-500, 517, 518, pl. iii, figs. 8-10; pl, vii, figs. 1, 3, 4. Productus, Swattow. Trans. St. Louis Acad. Sci., vol. i, p. 640. Productus, Haut. Fourteenth Rept. N. Y. State Cab. Nat. Hist., p. 99. Producta, A. Wincuett. Proc. Acad. Nat. Sci. Phil., vol. xiv, p. 411. Producta, A. Wincuetu. Ibidem, vol. xv, p. 4. Producta, A. Wincuetu. Ibidem, vol. xvii, p. 114. Productella, Haut. Paleontology N. Y., vol. iv, pp. 153-160, 162-184, pl. xxiii, figs. 1-11, 25-49; pls. xxiv, xxv and xxvi. Productella, Haut. Twentieth Rept. N. Y. State Cab. Nat. Hist., p. 245. Productus, Meek and WortHen. Geol. Surv. Illinois, vol. ili, p. 412, pl. x, fig. 3. Productus, A. Wixcuety. Proc. American Philos. Soc., vol. xii, p. 249. Productus (Productella), Hatt and Wuirrietp. Twenty-fourth Rept. N. Y. State Mus. Nat. Hist., p. 198. Productella, Nicuotson. Geological Magazine, n. s., vol. i, p. 118. Productus (Productella), Hatt and Waitrietp. Twenty-seventh Rept. N. Y. State Mus. Nat. Hist., explanation pl. ix, figs. 9, 10. Productus, Merk. U.S. Geol. Expl. 40th Parallel, p. 36, pl. iii, fig. 7. Productella, Rarupun. Proc. Bost. Soc. Nat. Hist., vol. xx, p. 17. Productella, Haut. Rept. N. Y. State Geol. for 1882, pl. (xvii) 48, figs. 1-9, 16-46. Productus (Productella), Waucorr. Pal. Eureka Dist., pp. 128-133, 214, pl. ii, fig. 10; pl. vii, fig. 2; pl. xiii, figs. 8, 9, 18-20. Productus, Herrick. Bull. Denison Univ., vol. iii, pp. 31-34, pl. iii, figs. 18, 28; pl. vi, fig. 16; pl. vii, fig. 18. Productella, NerrerrotH. Kentucky Fossil Shells, pp. 69, 70, pl. xvii, figs. 5-9; pl. xxvi, fig. 7. It is a natural presumption that the earlier forms organized on the pro- ductoid type of structure should retain the cardinal areas and articular pro- cesses of the valves, and it is upon the natural persistence of these features in many if not all of the Devonian species that the genus Propucre.ia was based. This group was founded on the Productus subaculeatus, Murchison,* a middle * This species was identified by M. pz VeRNxUIL as occurring in the American Devonian rocks near Charleston Landing, Indiana, and the fossil originally figured, as typical PRopucTELLA, was obtained from near Jefferson, in what was then regarded as the Corniferous limestone, but which later investigations have proved to be the calcareous beds representing the Hamilton group in its western extension. See Pal. N. Y., Vol. V, pt. ii, p. 189; “Note on the Hydraulic Beds and Associated Limestones at the Falls of the Ohio.” BRACHIOPODA. 329 Devonian form, and, as already observed, it is essentially equivalent to pE VERNEUIL’S division of the Producti caperati; certain small species which ex- tend into the earlier faunas of the Carboniferous still retaining the cardinal area and teeth. It is to be noticed that these features are in all cases obscure and frequently difficult to discern, but even the large species occurring in the late Devonian (Chemung) and early Carboniferous. (Waverly), and which resemble more in size and expression the normal species of the later faunas, do retain them. There is no reliable evidence that Propuctus, as we have used the term, occurs in Devonian faunas, and there is little reason to doubt that, in this country, it does appear as early as the Waverly group (P. Newberryi and P. semireticulatus). There are some peculiarities in Propuctetta which may prove of value in classification. The cardinal process rarely shows a trilobation when viewed from the posterior face, the bilobate character being about equally developed on both sides; the delthyrium is apparently covered on both valves; the muscular impressions of the brachial valve are very small, and their surface is not dendritic; the brachial ridges or reniform impressions are rarely retained, if ever present. The existence of teeth in the pedicle-valve implies the pres- ence of sockets and crural plates in the brachial valve. The latter are divergent ridges nearly parallel to the hinge-line, and corresponding to the thickened ridges lying just within the cardinal margin in most species of Pro- puctus. The combination of all these features, though they may not be suffi- cient to give to Propuctstta a thoroughly valid biological basis as a strongly marked and distinctly limited generic form, may nevertheless serve to con- tinue the usefulness of the designation in distinguishing certain forms among the barren mass of Productoid material, where individuality is feebly repre- sented, or entirely lost in the multitude of forms. With our present knowl- edge and views of classification it must be regarded that Propuctrrenia and Propuctus are members of a descending series and represent different stages in the process of degeneration. In the discussion of the characters of Pro- DUCTELLA, given in Volume IV of the Paleontology of New York (p. 151), the following observation was made: “It appears to me that we have in the De- 330 PALZVONTOLOGY OF NEW YORK. vonian period the incipient manifestation of the productidian type, which be- came modified in the later Carboniferous period, where, with conditions favorable to its excessive development, it has assumed extravagant forms and proportions, but here and there indicating the character of its prototype in the presence of an area and foramen, among species of a genus which is character- ized by the absence of these features. In the still later Permian period, with changed conditions, we have an approximate return to the earliest forms of the species, or to the prototype; and in reality the foundation of the genus lies in the Devonian forms which have been referred to STROPHALOSIA.” From the Carboniferous Producti Dr. Waacen proposed in 1884 to separate a group characterized by a prominent internal ridge situated just within the margins of the valves. To this group he gave the designation Marcinirera, and described it in the following terms: “The shells which I consider as belonging to the present genus are always rather small, and never attain any considerable dimensions. In their external appearance they are absolutely like Productus, so long as the shell is not bro- ken, but as soon as the shell-margin is removed, which very easily happens, the difference comes to light. The cause why the shell-margin so very easily breaks off is a thick, prominent shelly ridge, placed vertically on the internal surface of the dorsal valve, and by which the visceral part of that valve is girt. In the ventral valve a similar ridge is developed within the wings only. In this way the visceral part of the shell is perfectly chambered off from the remainder of the shell. These prominent concentric ridges are sometimes finely striated and crenulated ; sometimes smooth. The other internal charac- ters are in all the specimens at my disposal (except in Marg. typica, W., where the description will be found) very indistinct, but on the whole they seem to be similar to those of Productus. “This strange chambering off of the visceral part by means of proper pro- jecting ridges seems to me perfectly sufficient for the generic distinction of these forms. Certainly it is as well worthy of notice as the existence of an area in Aulosteges or the like.” (Salt-Range Fossils, p. 713.) BRACHIOPODA. 33] Fics. 28-30. Muarginifera typicu, Waagen. After WAAGEN, The peculiar features described may perhaps be valid ground for the proposed subdivision when in their extreme development, as in M. typica and M. ornata, Waagen (see figures in the work cited, plates Ixxvi and Ixxvii), but an examination of extensive collections shows that these . elements appear, in various stages of development, in different species, from the middle Devonian upward through the Coal Measures. In all the Amer- ican species examined, the characters on which this division is founded seem to be rather in an inceptive condition when compared with Marginifera typica, and can scarcely be considered as of such organic importance as to warrant the generic separation of such forms, especially when it will involve a considerable number of species in which the articulating apparatus and all the more essential characteristics correspond with Propuctus. Unless applied in a very restricted sense, this term can scarcely be adopted to designate an altogether reliable separation from Propucrus, for it is manifest that many species, possessing incipient internal characters which show them to be in the line of develop- ment toward MarcinirerA can not, on such grounds, be separated from the old genus, while the number of forms in which these characters described become fixed and highly developed, are very few. 332 PALHHONTOLOGY OF NEW YORK. Dr. Waacen has taken Norwoop and Prarten’s species, Productus splendens, as the type of the group which embraces his typical species, and further has expressed the opinion that the American species from the Coal Measures be- long for the greater part to Marernirera. It is extremely doubtful if the evidence will sustain this assumption though there are certain species of the Coal Measures, Productus splendens, Norwood and Pratten, P. longispinus, Sow- erby, P. Lasallensis, Worthen, which show the characters of MARGINIFERA in some stage of development. In the species Productus dissimilis, Hatt,* from the middle Devonian of Rockford, Iowa, and the upper Devonian of New York, similar internal char- acters are quite strongly developed, especially in the pedicle-valve, and in both valves the margins of the ridges are more or less distinctly crenulated. While the species has the cardinal area, teeth and sockets in an exceedingly obscure condition, the cardinal process is like that of Propuctrgtia, strongly bifurcated to its base, and its external surface presents characters rarely met with either in Propuctus or Propuctetia, but not uncommon in STROPHALOSIA; a spinifer- ous pedicle-valve, and a brachial valve without spines, but covered with con- centric lamellose ridges. * Mr. Watcorr has proposed to change the name of this species to P. Hallana (Monograph U. S. Geol. Surv., vol. viii, p. 130, 1884), as pz Konryck had used the same term for a Devonian species which is evi- dently a Propucratta. Should, however, the American species be referred to Maratyirera, its original designation may be retained. BRACHIOPODA. 333 Genus PROBOSCIDELLA, (Qatrrr. 1887. 1840. Productus, pe Vernevit. Bull. Soe. Géol. de France, vol. vi, p. 259, pl. iii, fig. 3. 1841. Clavagella, Gotpruss. Petrefacta Germanie, vol. ii, p. 285, pl. elx, fig. 17. 1841. Productus, von Bucu. Abhandl. der Konig]. Akad. der Wissensch. zu Berlin, Theil i, p. 40. 1843. Productus, DE Kontncx. Descript. Animaux Fossiles du Terr. Carb. de Belgique, p. 11, fig. 4. 1847. Productus, pe Koytnck. Monographie du genre Productus, p. 62, pl. vi, fig. 4. 1854. Productus, Norwoop and Prarren. Journ. Acad. Nat. Sci. Philadelphia, 2d Ser., vol. iii, p. 10. 1861. Productus, Davipson. British Carb. Brachiopoda, p. 163, pl. xxxili, figs. 1-4. 1880. Productus, DAvipson. British Carb. Brachiopoda, Suppl., p. 311, pl. xxxvi, fig. 13. 1887. Proboscidella, Giutert. In Fiscuer’s Manuel de Conchyliologie; Brachiopodes, p. 1277. Diagnosis. ‘“ Valves very unequal; the dorsal small, concave, operculiform ; the ventral larger, convex, furnished with two lateral expansions which bend downward to meet the margins of the dorsal valve, and an anterior expansion which is produced forward into along cylindrical tube, sometimes attaining twice the length of the shell; the suture appears on the dorsal side in the median line. Sometimes instead of a single tube there is a double enrollment resulting in two distinct tubes. The surface is ornamented by concentric plica- tions, traversed by fine radiating ribs, which are flexuous and close together ; the last plication, and the groove accompanying it, is sharper than the others and marks the separation of the ventral valve, properly speaking, from its lateral and anterior expansions upon which the concentric markings are rare, faintly developed or wholly wanting, while the radiating striz are regularly continued.” (CinteErt, loc. cit.) ; Carboniferous limestone. Type. Productus proboscideus, de Verneuil. Fics, 31-33. Productus (Proboscidella) proboscideus, de Verneuil. After DE KONINCK. 334 PALZ ONTOLOGY OF NEW YORK. Osservations. This term has been proposed for the species above men- tioned, in which the development of the shell is of such an extravagant char- acter as to have necessarily modified the functions and anatomy of the animal. Though the internal markings of this species have not been described, it is probable that they will prove not to vary materially from those of Propucrus, and even the external features are but a result attained along a line of develop- ment represented in such forms as P. striatus, Fischer, P. ermineus, de Koninck, P. genuinus, Kutorga, and not resting with P. proboscideus, but attaining an ex- treme in pE Konincx’s species, P. Nystianus, in which the pedicle-valve is de- veloped into two tubes, one on the frontal and one on the cardinal margin.* De Koninck has shown that in this last-named species the formation of these tubes is an accompaniment of decrepitude, and that the early stages of the shell conform to the normal form of Propucrus. No thoroughly satisfactory explana- tion of the function of these enrollments of the shell has been offered. De Koninck was disposed to regard them as passages for muscular fibers by which the animal was attached and p’Orxieny considered them as malformations. The former view requires too radical a modification of the internal anatomy, and, as to the latter, there can be no doubt that these tubes which are constant, though variable in form, size and even in number, are altogether normal. The further suggestion of p’Orsieny that the animal, from its constrained position, possibly buried in the sediments, was forced to prolong its shell so as to reach the surface of the sea-bottom, seems reasonable, and met with the endorsement of Mr. Davipson. The group is probably represented in American faunas by the imperfectly known P. clavus, Norwood and Pratten, from the Carboniferous of Illinois, a form which seems to be a close ally of the P. proboscideus of Visé and York- shire. . * See pe Koninckx’s figures of all these species ; Monogr. genre Productus, pls. i, vi, xiv. BRACHIOPODA. 39 Genus ETHERIDGINA, Qauterr. 1887. 1876. Productus, ErHERIDGE, JR. Quart. Journ. Geol. Society, vol. xxxii, p. 454, pl. xxiv, figs. 1-145 pl. xxv, figs. 15-24. é 1878. Productus, ETHERIDGE, JR. Quart. Journ. Geol. Society, vol. xxxiv, p. 498. 1880. Productus, Davipson. Monogr. British Carb. Brach. Suppl., p. 303, pl. xxxv, figs. 4-13. 1887. Htheridgina, Giuuert. In Fiscuer’s Manuel de Conchyliologie ; Brachiopodes, p. 1278. Diagnosis. “Shell of very small size, nearly as broad as long, attached to foreign bodies by the spines of the ventral valve; cardinal line straight, nearly equaling the greatest width of the shell; pallial outline semicircular; ventral valve with a small, entire [?| beak; surface ornamented by concentric flexuous plications, bearing a few scattered spines; cardinal process quadrifid.’”’— CHuLERT, wt. cit. Type, Productus complectens, Ktheridge, Jr. FIGs. 34-37. Productus (Etheridgina) complectens, Etheridge. After ETHERIDGE. OxsseRvations. ‘This shell was admirably described by Mr. Ernertner in his paper on “ An Adherent Form of Productus” (1876) and presents the interest- ing combination of distinctive productoid characters (absence of cardinal area, hinge, etc.), with a mode of growth characterizing the genus SrRopHALosta. The very small shells of this genus, which is thus far represented by the type species only, have been found adhering to crinoid columns and fragments of bryozoa; that is, to surfaces of little expansion; hence the creeping spines appear to effect an attachment by encircling or hugging their host. This ap- pearance is somewhat deceptive; the surface of the pedicle-valve is itself adherent, and the mode of growth of both shell and spines the same as that already observed in some of the small species of SrropHatosta (S. radicans, 336 PALEONTOLOGY OF NEW YORK. S. scintilla, S. Keokuk) which have usually been found attached to flatter sur- faces. Mr. Erueripce makes the following interesting observations on these fossils : “When the organism to which the Propuctus is attached is of larger size than the latter, the whole of the ventral valve is applied to it, the spines spreading out and around on each side; but when the foreign body is of less diameter than the Propucrtus, as is usually the case with fragments of Polyzoa, several of the spines are wound tightly round, especially near the beak, and the remainder of the valve remains free. Attachment took place during the life of the Crinoid; for in nearly every case where the Propuctus remains adhering, we find that its rate of growth was less than that of the Crinoid, the result being that the substance of the latter surrounded or enclosed its parasite, first the encircling spines disappearing and gradually the shell. We have specimens showing this remarkably well in all stages of the process, from the mere absorption of the spines by the substance of the Crinoid, up to the total disappearance of the Propuctus itself, when the Crinoid stem assumes a swollen or distorted appearance. From a consideration of this gradual absorption by the Crinoid stem there arise two questions: Did the Propuctus when once attached lose the power to free itself? or, Did the absorption by the Crinoid, contrary to the view indicated previously, commence only after the death of the Propuctus?”’ Some of Mr. Erneriper’s figures of this species, which is from the Lower Carboniferous limestone of Edinburghshire, Scotland, are here reproduced. 3964 BRACHIOPODA. leet; . EY $b a 8 = a a m mt I ry u ad fo f ¢ g 2 3 ne i a} Gh el re Ce Sete = Cee ee itt telat a Ee og ls 8 8 8 fi ee el oe Re bee ee, Fe oe Cel Ae fe 6 ey a 8 A Bs aw oe Fe 2 Ff S 8 8 ea ee Be eS FB ee eb eee ob be Se os 2 eS ee 6 og e aH ae € © Fi | She oO g 7G esl o SE pS 8 a SE SES 6p EH © Ee A oe ae as Bom oe Orrin #, = - - a 6 BILLINGSELLA, - - - ee PROTORTHIS, - - - - - — Cuiramponires, Pander, = - =| — | PoLyTascHIA, - - - -| — Hemipronites, Pander, -| Lower Silurian of Europe. Scenipium, Hall, - = - - EEE The tabular arrangement is intended to show the geological range of these genera, so far as known at the present time. ‘The material accessible for the study of the older groups (except Scenipium) is too meagre to afford ground for generalization. é £6 a me 2 Zz 2 S ao Fe Fe Sb hig ecuere 2 S 2 @ 8 d Gen sile| ele) Boa a # fe g ¢ BC Re oe a a ee Ge Be eB Ee S SG = ee ees Ee aul OS 2 SE in 4 A 4a Leprana, Dalman, - - -| = EG RAFINESQUINA, - - - = =e SrropHEoponta, Hall, - qe 2 TE PHOLIDOSTROPHIA, - - - — LEpPToOsTROPHIA, - - - - ee Bracuyprion, Shaler, - - —_<— Dovuvituina, Gthlert, - - - = SrRoPpHONELLA, Hall, - - - ee AMPHISTROPHIA, - - - - — LEPTELLA, - - - - - — PLEecTAMBONITES, Pander, = i> == CHRISTIANIA, - - - - —EEES Lepranisca, Beecher, - - - — Davinsonta, Bouchard, - - Middle Devonian of Enrope. Cyonetes, Fischer, - SSS ANOPLIA, - - - - a CHOoNETINA, Krotow, Permian of Russia. CHONOSTROPHIA, - - - - ——e Cxo /HONOPECTUS, - - - - — CHONETELLA, Waagen, - 5 Upper Carboniferous of India. — a ——_— Marainirera, Waagen, - - oa ae » PRoBoscIDELLA, Cthlert, - - - eae Erueripaina, Ghlert, | Coal Measures of Europe. BRACHIOPODA. 337 SUPPLEMENTARY NOTE ON THE GENUS OBOLUS, VON EICHWALD. The preceding discussions of the inarticulate genera (ending on page 184) were received from the printer in March, 1890. Since that date an impor- tant contribution to our knowledge of the genus Opotus has been made by A. Mickwitz,* whose studies are based upon finely preserved material from Joafall, near Jegelecht, Esthonia. Students of the brachiopoda will appreciate the author’s statement that “this genus, notwithstanding the exceeding abundance of its shells in the upper layers of the Ungulitensandstein of our Cambrian formation, from Baltischport to the banks of the Sjas, and in spite of its early discovery, has been hitherto as good as unknown.” The details of the internal structure of both valves are worked out with such a degree of elaboration, that we can do no less than give in this place the author’s diagnosis of the genus and copies of his accompanying illustrations, observing that the genera AuLonotreta, Kutorga, and Scumiptia, Volborth, are here regarded as synonymous with Oxotus : “Shell nearly equivalve, equilateral, depressed or slightly convex; outline circular or somewhat elongate longitudinally or transversely, in some species subtriangular or elongate-quadrate. “Shell-substance calcareo-corneous, structure laminated; surface lustrous, with concentric and radial striae varying to deeply incised transverse folds and radial ribs. Color of the shell dark greyish-blue to black; when in process of decomposition, whitish to dark brown-red. Anterior and lateral margins thin, sharply angled and fragile, lying in the plane of the greatly thickened cardinal margin. The cardinal area lies in the plane of the margins, in the larger valve being somewhat triangular on account of the elevation of the beak, and divided equally by the pedicle-groove ; in the smaller valve rounded at the apex, and in both striated parallel to the base, and grooved from apex to base by the * Vorlaufige Mittheilung tiber das genus Oxo.us, Eichwald: Mélanges géologiques et paléontologiqnes tirés du Bulletin de l’Académie Impériale des Sciences de St. Pétersbourg, Tome I. (Read October 9th, 1890.) 338 PALHZONTOLOGY OF NEW YORK. more or less divergent marks of the impressions of the lateral sliding muscles. The middle portion of the thickened margin slopes to the center of the shell, forming in the larger valve a line concave as to the beak, and in the smaller valve a sinus. The lateral portions of the thickened area merge gradually into the thin margins of the valves. Beneath the hinge-line in both valves is a narrow median septum, fainter in the small valve, and in both a scarcely visible ridge discernible only in oblique light. On either side of the septum begins a furrow which increases in depth and passes through the thickened area in a line parallel to the margins of the shell. “The impressions of the vascular trunks of the mantle are continued from these furrows into the anterior portions of the valves and parallel to their margins. Secondary vascular sinuses radiate in great numbers from the main trunks toward the margins and center of the shell. ‘In the median line of the larger valve, between the median septum and the anterior margin of the thickened cardinal region, lies a deep cordate pit, having its apex directed toward the anterior margin of the shell and with a shallow median furrow. In the sinus of the smaller valve is a faint median swelling, extending beyond the center of the shell and divided longitudinally by an . obscure groove. “ Muscular impressions in five pairs for each valve; two of the adductors and three of the sliding muscles. The impressions of the adductors lying directly beneath the cardinal margin, are separated in the larger valve and in juxtapo- sition in the smaller. The anterior pair in the larger valve lies on either side of the cordate pit, in the smaller at the apex of the corneous callosity, extending into the middle of the valve and forming the sinus. Of the sliding muscles there is a pair on each side of both valves, close to the cardinal margin and between the lateral furrows and the margins of the shell. In the larger valve these scars are in juxtaposition, but in the smaller they are further apart, touching only at their extremities. The third pair of these impressions in the larger valve lies close against, but outside the anterior adductors; in the smaller valve on either side of the anterior extremity of the median swelling, in the sinus, and nearer together than the scars of the anterior ad- ductors. The scars of the paries passes closely about the muscular impres- sions, crossing both lateral furrows and terminating in the central portion of the cardinal margin.” BRACHIOPODA. 339 Larger valve. Smaller valve. FIGs. 88, 39. Diagrammatic view ot Obolus Quenstedti. After MICKWITZ. a, Pedicle-groove; 0, impression left by the advance of the’ lateral sliding muscles; c, median septum; d, cordate pit; e, sinus; 7, median groove; g, median swelling; h, lateral grooves; 7, impressions of vascular trunks; &, impressions of secondary sinuses; J, impressions of posterior adductors; m, impression of anterior adductors; n, impressions of sliding muscles; 0, outline of splanchnoccele; I, splanchnocewle; II, brachioccele; III, pleurocele. According to this diagnosis, the analogies of Opo.us, with Lingua are at once striking, though there are important differences. In L. anatina there are four pairs of lateral or sliding muscles, while there appear to be but three in Obolus Quenstedti; according to Micxwitz the anologue of & (middle lateral in Lineura, see figure on page 10), being absent in the latter. The adductors are the same in number in both, though there is considerable difference in their disposition; the position of the posterior band, which is divided at its ventral insertion being the same as that of the great umbonal in Lineuna. In Lineuna, again, Kine has shown that one of the transmedian bands is divided, which does not appear to be true of Obolus Quenstedti. It must be observed that these results have not been obtained from fin type- species of the genus, Obolus Apollinis, von Kichwald, but from a hitherto unde- scribed form. Experience has taught us that the greatest care is required in the discrimination of generic values among the oboloid genera of the early palzozoic faunas, and it may be a question for subsequent. determination whether a species showing so many important differences from the structure hitherto known in O. Apollinis should be regarded as congeneric with it. Attention is called to the similarity in many points of structure of O. Quenstedti with the genus Opo.e.ta, Billings, as shown in the figures on Plate II of this volume. 340 PALHONTOLOGY OF NEW YORK DESGRIPTIONS OF NEW SPECIES FIGURED IN THIS VOLUME. ~ Ortuis? SarrorDi, sp. nov. PLATE V4, FIGS. 38-40. SHELL semielliptical in outline; valves subequally convex, the pedicle-valve being the more elevated at the apex. Hinge-line long and straight, giving the shell a strophomenoid appearance. Cardinal area low; delthyrium un- covered. Surface covered with numerous rounded, sharply elevated strize, increas- ing by intercalation, and crossed by exceedingly fine concentric lines. The details of the interior are not known, but the relations of the shell to Ortuis are demonstrated by the open delthyrium and simple cardinal pro- cess, slightly lobate on its posterior face. Length of the type specimen, 17 mm.; width along the hinge, 22 mm. Trenton horizon. Hast Tennessee. Orrtuis ? Hotstoni1, SAFFOoRD. PLATE VA, FIGS. 35-37. SHELL transverse; outline semicircular. Hinge-line long and straight. Pedi- cle-valve with a high, vertical, cardinal area, transected by a very broad, uncovered delthyrium; beak not incurved; surface sloping evenly toward the margins, slightly rounded in the median line, and faintly depressed toward the cardinal angles. Brachial valve depressed convex, nearly flat, with a broad and low median sinus. Surface of both valves covered with fine, elevated, radiating stri, crossed by faint, concentric, cancellating lines which have a slight retral bend on the strie. This shell has very much the aspect of a CurramponirEs, but of the two specimens examined, neither has evidence of a deltidium, and a trans- BRACHIOPODA. 341 verse section across the umbo of one, shows that the dental lamellae, though strong and convergent, did not unite to form a spondylium. Received from Professor SAFrorp. Trenton horizon (Glade limestone). Near Nashville, Tennessee. OrtHis (PLASIOMYS) LORICULA, sp. nov. PLATE VA, FIGS. 32-34. SHELL strophomenoid in outline; reversed convex. Hinge-line long and straight making the greatest diameter of the shell. Cardinal areas narrow, subequal. In the pedicle-valve the delthyrium is covered by a convex plate extending for one-half its length; the area is erect, the beak not prominent. The valve is slightly convex in the umbonal region but is depressed outward in all directions, most strongly in the median line. The brachial valve is de- pressed about the beak, convex over the pallial region and divided in the median line by a shallow sinus. The interior characters of the valves are essentially the same as those in Orthis subquadrata. External surface covered with numerous fine, elevated striz, alternating in size and crossed by finer concentric lines. Length of an average specimen, 18 mm.; width, 21 mm. Trenton horizon. Fountain, Minnesota. Ortuis (DALMANELLA) ARCUARIA, Sp. nov. PLATE VC, FIGS. 20, 21. SHELL with a general similarity to that of Orthis elegantula, Dalman, but having the marginal outline more circular, the pedicle-valve more evenly convex, the umbo more prolate, and the brachial valve considerably more convex. The pedicle-valve bears a broad fold, and the brachial a shallow sinus, in the median line. In the interior of the pedicle-valve the muscular area is elon- gate and very deeply impressed, the umbonal portion of this valve being considerably thickened. 342 PALZAONTOLOGY OF NEW YORK. Surface covered with numerous very fine radiating striz. Length of the type specimen, 19 mm.; width, 18 mm.; depth, 9 mm. Hudson River group. Hast Tennessee. Ortuts (DALMANELLA) SUPERSTES, sp. nov. PLATE Vc, FIGS. 44-47. Seti of small size and having the general form and expression of O. hybrida Sowerby. Hinge-line short, beaks but slightly elevated. Marginal outline varying from subquadrate to subcircular. Valves about equally convex. In the pedicle-valve the beak is somewhat inflated and slopes evenly in all directions for nearly one-half of the shell; from this point onward is a broad, low median sinus, which is most conspicuously developed in old and gibbous shells. In rare instances there is a low elevation in the bottom of this sinus The opposite valve also bears a median sinus which takes its origin at the beak. In the interior of the pedicle-valve the muscular area is sharply de- fined, subquadrate in outline, the adductor scars small and the diductors well developed. In the brachial valve the cardinal process and crural plates are prominent; the muscular area well defined and quadruplicate. The external surface of the valves is covered with fine, elevated striwe, of which twenty of the coarsest reach the beak; this number increasing by intercalation to about fifty at the margin. Near the margin very fine concentric strize are visible. Length of a normal individual, 12 mm.; width, 15 mm.; depth, 9 mm. Chemung group. Near Howard, Steuben county, N. Y. Orruis (RuIPIDOMELLA) OWENI, sp. nov. PLATE VI, FIGS. 19-21. Snett having somewhat the outline of O. Vanuremi, but more elongate trans- versely and gently sinuate or emarginate on the antcrior edge. The shells are usually flattened, but where the form is retained the pedicle-valve shows a hinge-line whose length is somewhat less than one-half the transverse BRACHIOPODA. 343 diameter of the shell. The beak is acute, the umbo full but not conspicuous. Along the center of the valve is a broad, low sinus, frequently very in- conspicuous. The interior of this valve is characterized by the relatively small area covered by the muscular scars, a feature in which it resembles O. Peloris of the Schoharie grit. The pallial region is pitted or covered with faint, closely anastomosing ridges. On the brachial valve the median sinus begins at the apex and becomes very pronounced as it widens anteriorly. From the ridges forming its lateral margins the surface slopes rather abruptly and without much curvature. On the interior the cardinal process and crural plates are not prominently elevated; the muscular area is small, quadripartite, the lateral pairs of scars being separated by a broad, thick ridge. Surface of both valves covered by a great number of fine radiating, hollow strie, from 110 to 130 in number, which are crenulated by minute con- centric lines and crossed at intervals by coarser lines of growth. The surface was originally covered with short spinules, which are rarely pre- served. This shell has heretofore been commonly referred to Orthis Michelini, Léveille. Keokuk group (Knobstone formation). Button-mould Knobs, Kentucky. Ortuts (SCHIZOPHORIA) SENECTA, Sp. Nov. PLATE VIA, FIGS. 23, 24. SHELL subquadrate or transversely elliptical, resupinate, unequally biconvex. The pedicle-valve is depressed convex in the umbonal region and develops a broad, low median sinus toward the anterior margin. The brachial valve is the more convex and slopes evenly toward the lateral margins, the median region being rendered slightly more prominent by an obscure fold. Internal markings as in other members of ScuizopHorta. External surface covered with fine, subequal, closely covered radiating striz. Length of a typical example, 17 mm.; width, 21 mm. Clinton group. “Reynale’s Basin, Niagara county, New York. 344 PALHZONTOLOGY OF NEW YORK. SrROPHOMENA CONRADI, sp. nov. PLATE IX A, FIG. 3; AND PLATE XX, FIGS. 322, 33. SHELL semiovate in outline; hinge-line straight and forming the greatest diameter of the shell.. Cardinal area narrow on both valves; broader on the pedicle-valve and but slightly elevated at the umbo. Delthyrium covered ; deltidium perforated at the apex. Pedicle-valve convex in the umbonal region, but becoming deeply depressed and concave over the middle of the shell and again elevated about the margins. The depression of the valve is most conspicuous along the median line and on the anterior margin where it produces a subnasute extension. The brachial valve is flat or slightly con- cave at the umbo, becoming convex over the pallial region; it reaches its greatest convexity at about the middle of the shell and is thence deflected gradually in the median line and more abruptly on the lateral slopes. Surface of the shell covered with radiating striz, arranged in fascicles of 4 to 7 fine ones between each pair of coarser ones ‘There are no con- centric ruge on either valve, but the radiating striz are crossed by ex- ceedingly minute concentric lines. Width of the original specimen along the hinge, 25 mm.; greatest length, 19 mm. Trenton limestone. Jacksonburg, N. Y. SrropHOMENA WINCHELLI, sp. nov. 1883. Strophomena nutans, Hatt. Rept. State Geologist N.Y. for 1882, expl. pl. (ix) 39, figs. 10, 12-14. PLATE IX, FIGS. 10, 12-14; PLATE XX, FIG. 26. SHELL elongate semiovate; strongly convexo-concave. Hinge-line straight and making the greatest diameter of the shell. Cardinal angles sometimes ex- tended. Pedicle-valve with a moderately broad area and deltidium; apex slightly elevated, the valve becoming deeply concave over the pallial region and reflected at the margins. The teeth are strong and divergent, and from their bases extend elevated curving ridges which form the margin of the subcircular or subovate muscular area. Diductor scars broad, enclosing an BRACHIOPODA. 345 elongate and narrow adductor. Within the anterior and lateral margins of the valve is a thickened ridge which is crossed by branches of the vascular sinuses. Brachial valve flat in the umbonal region, very convex over the median portion and sloping gradually to the margins. The cardinal process consists of two slender and short apophyses which are united at their base with the crural plates. The latter are very divergent and extend in a broad curve subparallel to the hinge-line. The muscular scars consist of two pairs, the posterior being broad and striated, the anterior narrow and close to the median line. The members of the pairs are separated by a low median ridge. Surface of the shell covered with numerous very fine filiform strie, regu- larly but not conspicuously alternating in size. Delicate concentric striz are sometimes discernible. Trenton horizon. Clifton and Janesville, Wisconsin. This shell has been referred to the Hemipronites nutans, James (Meek), of the Hudson River, group which it resembles in its general expression. It differs from that species in its internal characters and more finely and abundantly striated exterior. ORTHOTHETES DESIDERATUS, Sp. Nov. PLATE IX A, FIGS. 26, 27. 1883. Streptorhynchus, sp. ? Hatt. Rept. State Geologist N. Y. for 1882, pl. (xi a) 42, figs. 26, 27. TuE original specimens of this species are internal casts of a form with a sub- circular marginal outline, very gibbous -brachial valve which has its greatest convexity central and slopes evenly to the margins, though with a slight tendency to depression toward the cardinal extremities; a strongly and reg- ularly concave pedicle-valve, elevated at the beak and about the margins. The cardinal area on this valve is moderately high and erect, the hinge-line being slightly shorter than the greatest diameter of the valves. The sur- face of both valves is covered with numerous fine radiating strise. The general form and contour of the species is very similar to that of Orthothetes umbraculum of the Hifel. Waverly group. Medina county, Ohio. 346 PALHZONTOLOGY OF NEW YORK. DerBYA RUGINOSA, sp. nov. PLATE XIA, FIGS. 25-27. Sne.t subelliptical in outline. Hinge-line short, its length being about two- thirds the greatest diameter of the shell. Pedicle-valve shallow; cardinal area moderately high, its lateral slopes being slightly more than one-half the length of its base; apex scarcely prominent; surface depressed or flat in the umbonal region, becoming irregularly concave anteriorly. Entire valve very irregular in growth, with concentric ridges and furrows. Brachial valve very convex; apex depressed, but the umbonal region gibbous, the greatest convexity being reached at the center of the valve. This valve is also of irregular growth, though the irregularities are not so strongly developed as_ on the opposite valve. The original specimen is an internal cast in chert to which portions of the inner lamine of the shell adhere. There are evi- dences of a flabellate muscular scar on the pedicle-valve and a short ovate muscular area in the brachial valve. The traces of the surface striz preserved show them to have been very fine and numerous. Keokuk limestone. New Providence, Indiana. This species is similar in some general respects to Derbya Broadheadi, but differs in its narrower and lower cardinal area, less convex umbo on the brachial valve and in the absence of a median sinus on this valve. It may be compared with the Streptorhynchus crenistria, var. senilis, Phillips (Davidson), from the lower Carboniferous of Great Britain. DerByaA? COSTATULA, Sp. nov. PLATE XIs. FIGS. 16,17. Suect small, outline semi-oval. Hinge-line nearly equal to the greatest diameter of the valve. Cardinal area moderately high, with a prominent deltidium very wide at the base. Pedicle-valve with an elevated beak from which the surface slopes to the margins with a tendency to irregular growth. Brachial valve faintly depressed at the umbo, but otherwise pretty regularly convex, BRACHIOPODA. 347 the most elevated point being a little behind the middle of the valve. There is faint median sinus over the anterior region. Surface marked with a few coarse radial ribs, between each two of which are implanted one, two or three much finer ones. These ribs are crossed by a few distinct concentric varices of growth. Chester limestone. Crittenden county, Kentucky. This species is readily distinguished by the character of its surface orna- mentation, and though the interior features of the shell are as yet unknown, a very closely allied form from the upper Coal Measures near Kansas City has a well developed median septum in the pedicle-valve, and is hence to be referred to the genus Dersya. DersyA BroapHEADI, sp. nov. PLATE XIA, FIGS. 23, 24. Suetn with irregularly suboval marginal outline. Hinge-line short, its length not exceeding, and usually less than one-half the greatest diameter of the valves. Cardinal area of the pedicle-valve high, sometimes regularly tri- angular, often distorted or somewhat incurved; deltidium broad at the base and rapidly tapering with a faint median groove on its surface. Pedicle- valve convex in the umbonal region, irregularly rugose and depressed over the pallial area. Brachial valve very gibbous at the umbo, the greatest con- vexity being behind the center of the valve. From the umbonal region the surface slopes evenly toward the lateral and anterior margins, but is more abruptly depressed toward the cardinal extremities where it forms short sub- alate expansions. ‘The valve is but slightly unsymmetrical and is bilobed by a conspicuous median sinus which takes its origin near the umbo, and widens to the anterior margin. Surface covered by fine radiating striz which are of subequal size over the umbonal region, but toward the margin became arranged in fascicles on account of the addition of finer striz as growth advances. Concentric rug and growth-varices are frequent, especially on the pedicle-valve. Upper Coal Measures. Near Kansas City, Missouri. 348 PALHIONTOLOGY OF NEW YORK. Dersya BENNETTI, sp. nov. PLATE XTA, FIGS. 34-39. Suet. subtrihedral in general aspect, quite irregular in its growth. Hinge- line short, its extremities on both valves being auriculate. Pedicle-valve much the more irregular in growth, sometimes retaining the scar of attach- ment at its apex. Cardinal area unusually high, narrow, erect or slightly incurved, and frequently distorted ; delthyrium curved. General surface of the valve depressed-convex in the middle, sometimes rapidly sloping in all directions, at others concave in the umbonal region; as a rule very unsym- metrical. The brachial valve is deep, more regularly convex and has a full rounded umbo and a conspicuous median sinus. On the interior the pedicle- valve bears an extremely high median septum which is united with the den- tal ridges near the apex. The cardinal process is high, erect and deeply bilobed, each of its apophyses being strongly grooved on its posterior face. Other internal characters unknown. The surface of both valves is covered by fine, elevated, thread-like strize increasing very slowly by intercalation. The edges of these strize bear nu- merous minute asperites which may be due to the crossing of fine concentric lines. Irregular lines and wrinkles of growth are abundant near the margins. Upper Coal Measures. Near Kansas City, Missouri. DERBYA CYMBULA, Sp. nov. PLATE XIB, FIGS. 2, 3. Suet. large ; marginal outline transversely subelliptical. Hinge-line straight, its length being about two-thirds the greatest diameter of the shell. On the pedicle-valve the cardinal area is high, its base being one-third longer than its sides, and it may be somewhat unsymmetrical from distortion. Its surface is finely striated both longitudinally and transversely, and is divided into an outer and inner portion by two lines diverging from the apex and meeting the hinge-line half-way between its extremities and the edges of the deltidium. Deltidium broad at the base, rapidly narrowing for one-third its length, BRACHIOPODA. 349 thence tapering more gradually to the apex; its surface is marked by a well- defined median groove for its entire extent. The surface of the valve is elevated in the umbonal region and slopes somewhat irregularly to a low depression over the pallial region and about the margins. The brachial valve is broadly concave at the umbo, but rapidly becomes regularly convex, the greatest convexity being in the middle of the valve, whence it slopes almost equally in all directions. There is no evidence of a tendency to irregu- lar growth in this valve. Surface covered with numerous fine, sometimes irregular striz, increasing by implantation. Over the umbonal and pallial regions these striz are of about equal size, but about the margins the tendency to fasciculate arrange- ment is more apparent. Interior structure, except the existence of a median septum in the pedicle-valve, unknown. Upper Coal Measures. Near Kansas City, Missouri. DeRBYA AFFINIS, sp. nov. PLATE XI, FIGS. 4, 5. Suett subsemicircular in outline, somewhat transverse. Hinge-line straight, nearly equaling the greatest diameter of the valves. Cardinal area of the pedicle-valve high, its greatest height being about equal to one-third the length of the hinge-line ; divided by diverging lines as in the preceding species and crossed by conspicuous horizontal and fainter vertical striations. This area is often much distorted. Deltidium having a width at the base equal to one- fifth the length of the hinge-line; it tapers evenly to the apex and bears a median groove on its surface. The umbo is elevated, but the surface of the valve becomes depressed, irregular in growth and concentrically wrinkled, though not concave anteriorly. Brachial valve faintly depressed at the apex, but rapidly becoming convex, the greatest convexity being in the umbonal region, whence the slope is quite regular in all directions, being somewhat more abrupt toward the cardinal extremities. This valve also shows a slight tendency to unsymmetrical growth in the umbonal region. 300 PALHZONTOLOGY OF NEW YORK. Surface covered by sharply defined, sub-equal radiating strize, which in- crease by implantation. The grooves between these striae are deep, and both strise and grooves are crossed by fine concentric lines, which on the former produced a series of sharp asperities. Interior, with the exception of the median septum in the pedicle-valve, unknown. Upper Coal Measures. Near Kansas City, Missouri. There are many points of similarity in the Orthis Kaskaskiensis, McChesney, from the Kaskaskia limestone, Derbya cymbula and the species under consid- eration. All have the same general aspect. In O. Kaskaskiensis the brachial valve is most convex at the umbo, the pedicle-valve generally concave and the hinge-line equal to the greatest diameter of the shell; in Derbya affinis the brachial valve also has its greatest convexity at the umbo, but the hinge-line is considerably shorter than in McCuesney’s species, and there is a notable difference in the character of the surface strize; while in Derbya cymbula the convexity of the brachial valve is greatest at its center, the hinge-line very short and the pedicle-valve concave or depressed only over the pallial region. Dersya (2?) BILOBA, sp.-nov. PLATE XI, FIGS. 4, 5. Suet small, obcordate in outline. Hinge-line short and straight, its length being considerably less than one-half the width of the shell. On the pedicle- valve the cardinal area is moderately high and slightly arched backward ; delthyrium covered. The surface of the valve is somewhat depressed or flattened over the pallial region. The brachial is deeper and more convex ; the umbo is full but not elevated, and just in front of the apex there begins a broad and conspicuous sinus which widens rapidly and renders the shell bilobate on its anterior margin. Surface covered with numerous fine radiating striz. Interior unknown. Upper Coal Measures. Winterset, Iowa. BRACHIOPODA. 351 STREPTORHYNCHUS ULRICHI, sp. nov. PLATE XIp, FIG. 15. Suet. of comparatively large size for this genus. General contour subtrihedral. Hinge-line shorter than the greatest diameter of the valves. Cardinal area high, somewhat incurved and distorted; sides considerably shorter than the base. Deltidium broad. Marginal outline of the pedicle-valve, from hinge- line forward, semiovate, somewhat irregular, contracted toward the hinge and expanding in the pallial region. The interior of the pedicle-valve shows strong teeth, the dental lamelle extending downward and enclosing the posterior portion of an ovate muscular scar. There is no median septum. External surface convex in the upper part becoming depressed toward the anterior margin; quite irregular in growth, being crossed by more or less conspicuous concentric ridges or varices; covered with numerous fine radi- ating, subequal strize which increase by implantation. Brachial valve not known. Chester limestone. Crittenden county, Kentucky. CHRISTIANIA SUBQUADRATA, Sp. NOV. 1883. Leptena subquadrata, Haru. Rept. State Geologist N. Y. for 1882, pl. (xv) 46, figs. 32, 33. PLATE XV, FIGS. 32,33; PLATE XVa, FIG. 36; PLATE XX, FIGS. 18=20. SHELL small, elongate, semielliptical in outline, strongly convexo-concave. Hinge-line short, straight, not equaling the greatest diameter of the valves anteriorly. In the pedicle-valve the umbo is full, rounded and incurved, with the apex obscure; the cardinal area is moderately broad and bears an open delthyrium which terminates above in a circular foramen. The teeth are short, divergent and continued into ridges which form the lateral mar- gins of two linguiform, muscular scars, traversing the shell for almost its entire length. These scars enclose two much shorter impressions. In the brachial valve the area is narrow, the cardinal process bipartite on its an- terior face,-each of the lobes being grooved behind. The crural plates are very long and divergent, the upper portion of each terminating in an elevated 392 PALHZONTOLOGY OF NEW YORK. extremity; the lower portion produced on each side as a strongly elevated ridge, curving slightly inward on the sides, then outward on approaching the anterior margin of the valve; each branch recurving and passing back- ward, parallel to the median axis, as far as the base of the cardinal process. The symmetrical spaces thus formed are each divided transversely by a somewhat lower vertical ridge. Between the inner muscular walls in the median line is a low, rounded, longitudinal ridge. The surface is smooth or covered with concentric, usually somewhat squa- mous lines of growth. Lower Helderberg group. Perry county, Tennessee. LEPTANISCA ADNASCENS, Sp. NOv. PLATE XVA, FIGS. 22, 23. SHELL small, very irregular in outline; cemented to shells of other brachiopods, especially of Orruts, by the entire external surface of the pedicle-valve. Hinge-line making the greatest diameter of the shell. Cardinal area well developed on the pedicle-valve and bearing a convex deltidium. Internal characters as in L. tangens. Brachial valve prominent at the beak, elevated in the umbonal region and slightly depressed anteriorly. Surface smooth or with irregularly concentric wrinkles. Lower Helderberg group (Shaly limestone). Near Clarksville, N. Y. LEPTANISCA TANGENS, Sp. nov. PLATE XVA, FIGS. 24-30. SHELL transverse ; hinge-line making the greatest diameter ; contour regularly convexo-concave; attached by the apical or umbonal portion of the pedicle- valve, usually fronds and twigs of bryozoa. Cardinal areas narrow; del- thyrium covered. In the pedicle-valve teeth not prominent but continued into strong, converging lamella which nearly enclose an oval muscular area ; this area is divided by a median septum. External surface convex ; bi- BRACHIOPODA. 353 lobed by a more or less conspicuous median furrow. Brachial valve strongly concave. Surface smooth, with a few inconspicuous concentric growth-lines, and faint radiating strie on the inner lamelle toward the margins. Lower Helderberg group (Shaly limestone). Near Clarksville, N. Y. CHonostRopHIA HELDERBERGIA, sp. nov. PLATE XVs. FIG. 14. SHELL tenuous, semi-elliptical in outline. Hinge-line straight and making the greatest diameter of the valves. Valves nearly flat, the pedicle-valve being gently concave and the brachial correspondingly convex. Cardinal areas very narrow; marginal spines not observed. ‘Teeth of the pedicle-valve well developed on either side of the moderately broad delthyrium ; at their bases arises a median septum, strongest at the point of beginning and continuing for one-half the length of the valve. In the brachial valve the crural plates are very short, subparallel to the hinge-line and apparently coalesced with the short cardinal process. No traces of muscular scars re- tained. Surface covered with a great number of exceedingly fine, subequal radiating striz, all of which are apparent on the interior of the shell, even to the bases of the teeth and crural plates. Lower Helderberg group (Shaly limestone). Albany county, N. Y. STROPHALOSIA ROCKFORDENSIS, sp. nov. PLATE XVIIA, FIGS. 1-3. SHELL semielliptical in outline, somewhat elongate. Hinge-line scarcely as long as the greatest diameter of the valves. Cardinal area well developed on each valve, that of a pedicle-valve bearing a convex deltidium; scar of attachment on the pedicle-valve covering only the apical region. Sur- face regularly convex, depressed toward the cardinal angles; bearing scat- 354 PALHONTOLOGY OF NEW YORK. tered spines, of which there is a well-defined row of six or seven on the car- dinal margin. There are faint, irregularly concentric wrinkles among the spine-bases. Apex of the brachial valve convex but the valve rapidly be- comes concave, being of somewhat less curvature than the opposite valve. Surface with conspicuous, irregular, concentric corrugations, and a few short spines over the pallial region. Length of the original specimen, 9 mm.; width along hinge-line, 10 mm. Upper Devonian. Rockford, Lowa. Page 57, line 12 from bottom; for ‘‘ Plate 1” read ‘‘ Plate II.” Page 75, line 6; for “position” read ‘ portion.” Page 83, line 5; for ‘‘ Lyoropotus” read ‘‘ Lepropo.us.” Page 99, line 23; for ‘“‘and” read ‘‘are.” Page 99, line 24; insert ‘‘ which” after ‘25-29).” Page 108, under fig. 60; for ‘‘ pedicle” read ‘brachial ; ” for ‘ brachial” read ‘ pedicle.” Page 139, line § from bottom ; SHARPE’s specimens came from Cincinnati, Ohio, or vicinity, and were probably examples of the form now known as 7’. millipunctata, Hall, as Emmons’ T. terminalis has not been found in that locality. SHARPE, however, mentioned Emmons’ species as the type, and it may be best to retain the New York form as such. Page 178, line 4; for “ Lingula lingulata” read ‘ Lingula linguata.” Page 185, line 18; for “‘SrropHoponra ” read ‘‘ StROPHEODONTA.” Page 194, second paragraph. ‘The deltidium of Orthis? Laurentina is minutely perforate. Page 288, line 15; dele ‘‘are.” Page 303, line 2; for ““XVa” read “XVs.” Page 308, line5; for “C. undulatus” read **C. undulata;” for ‘*C. Novascoticus” read C. Nova- scotica.” Corrected in part of the edition. Page 328, line 1; for 1847” read “1867.” Explanation of Plate I, line 25; insert ‘(?)” after ‘“Lingula Vanhornii, Miller”; line 28, dele; read “Trenton horizon. Frankfort, Kentucky.” Explation of Plate [Vz, continued, line 8; for ‘ Orbiculoidea pulchra” read ‘‘ Orbiculoidea Herzeri.” Explanation of Plate 1Vr, line 33; for ‘‘ Orbiculoidea pulchra”’ read ‘‘ Orbiculoidea Herzeri.” INDEX TO PALZONTOLOGY OF NEW YORK, VOL. VIII, PART I. I. Reatsrer or AurHors’ NaAMEs. (These references do not include names used in association with specific designations.) PAGE. Abich, H., é 3 5 3 : : 261, 263 Agassiz, L., 233 Aldrovandus, 0 . 186 Ami, H. M., 79, 113, 115 Angelin, N. Dy 3 3 . 204 Archiac, E. J. ie D.deSt. S. ‘a, 253, 303, 317 Ast, Ph., : : , , 5 PAKS Barrande, J., 36, 63, 78, 78, 79, 98, 101, 105, 127, 133 134, 142, 200, 272, 273, 274, 285, 290 Barrett,S.J., . 5 5 120, 142, 144, 285 Barrois, C., ? 285 Bayan, F., 5 S 6 264, 266 Beecher, C. E., 146, 189, 206, 209, 254, 272, 273, 277, 290 291, 300, 301 Bergman, 218 Beuth, F., 3 0 : , 0 145 Billings, E., 3, 27, 33, 36, 40, 41, 44, 45, 56, 66, 67, 70 2, 75, 76, 78, 90, 91, 97, 98, 101, 103, 120, 138, 142, 145 187, 188, 192, 194, 195, 196, 198, 201, 205, 208, 211, 217 221, 230, 232, 288, 242, 244, 245, 253, 269, 276, 281, 284 285, 286, 288, 290, 294, 295, 298, 303, 304, 311 Binney, W. G., 2416 Bittner, A., . 6 0 6 0 298 Blainyille, H. M. D. de, 245, 246, 247, 249, 250, 252, 279 Bolten, 5 6 : : O O 2 Bouchard, 5 5 5 ; 0 OO Bronn, H. G., 6 2 9 : : 2,80, 186 Brooks, W. K., c 6 5 a 3 62) Bruguiére,J.G., . z 5 é C 5 4 orl Buch, L. von, 80, 189, 200, 201, 204, 211, 221, 233 253, 267, 276, 290, 303, 321, 333 Calvin, S., : 188, 206, 285 Carpenter, W. B., a . 6 . 149 Castelnau, F. de, 187, 200, 250, 276, 281, 303 Chemnitz, J. H., 6 é 5 3 5 Bui Clarke, J. M., 3, 121, 146, 189, 206, 209, 254, 272, 273 277, 290, 291, 304 Conrad, T. A., 2, 56, 59, 186, 187, 192, 196, 198, 200, 201 204, 205, 253, 257, 276, 280, 281, 284, 290, 295, 303, 321, 328 Cotton, H., 5 : 5 3 6 : eo, Cox, E. T., . 8, 187, 211, 264 Cuvier, G. C. F. Dy 122, 145, 150 Da Costa, E. M., : 6 9 3 b 321 Dall, W. H., 2, 14, 33, 34, 36, 44, 45, 83, 118, 120, 121 122, 123, 128, 138, 145, 150, 151, 155, 160, 236, 277 Dalman, J. W., 186, 191, 192, 204, 205, 233, 236, 276, 277 280, 290, 295, 296, 297, 303, 321 PAGE. Dana, J. D., : Z - . 5 Davidson, '., 0 8, 9, 10, 14, 15, 16, 17, 18, 19, 21, 22, 27, 31, 33, 34, 35, 36, 39, 40, 41, 43, 44, 45, 46, 51, 55, 56, 57, 58, 62, 63, 65, 66, 78, 79, 80, 83, 84, 85, 90, 91, 94, 98, 100, 101, 103, 107, 108, 110, 111, 112, 115, 120, 122, 125, 126, 127, 128, 129, 133, 138, 141, 147, 148, 149, 150, 151, 152, 155, 156, 158, 160, 191, 193, 200, 201, 202, 203, 204, 205, 211, 212, 214, 227, 241, 242, 243, 245, 216, 249, 250, 253, 254, 257, 259, 264, 267, 268, 269, 270, 271, 274, 279, 230, 281, 284, 286, 290, 295, 296, 297, 298, 300, 301, 303, 304, 306, 314, 317, 319, 320, 324, 333, 334, Dawson, J. W., . 70, 107, 120, 285, 304, Derby, O. A., . 120, 145, 188, 208, 211, 213, 214, 254, 261, 267, 268, 304, 314, Defrance, 5 245, 246, 247, 249, 250, Dumeril, A., 5 6 } . 0 o 2 Dwight, W. B., 116, 126, Dyer, C. B., 138, Eichwald, E. von, 80, 110, 152, 200, 201, 221, 245, 266, 269, 276, 297, 298, 321, Emerson, B. K., s : 6 ° o Bh Emmons, E£., 2, 3, 56, 188, 145, 186, 195, 200, 205, 245, 257, 269, 281, Endlicher, 5 6 5 5 0 5 Etheridge, R., a 5 : : ‘ 5 335, Evans, Fahrenkohl, Deo Fischer de Waldheim, Foerste, A. F., 249, 253, 256, 303, 317, . 188, 189, 193, 198, 201, 206, 228, 254, 291, Ford, S. W.,. 51, 56, 66, 67, 68, 69, 70, 71, 72, 75, 76, 77, Frech, F., Garnier, F., : : , 6 A 150, 214, 217, 264, 267, 304, 514, Geinitz, H. B., Goldfuss, A., 303, 321, Gould, A. A., Gratiolet, P., 5 c . : : Gray, J. E., 5 9 : 9 a C Guillier, A., : 2 5 Gurley, W., 6 . : 6 : : O Hall, J., D . 2,38, 14, 18, 33, 36, 40, 44, 46, 56, 59, 66, 67, 69, 73, 87, 91, 120, 122, 138, 142, 145, 155, 187, 192, 194, 195, 196, 198, 199, 200, 201, 202, 205, 206, 209, 211, 214, 230, 240, 245, 246, 249, 253, 254, 257, 264, 269, 272, 276, 277, 281, 284, 285, 290, 291, 295, 300, 303, 304, 310, 312, 314, 319, 521, 322, 323, 356 PAGE. Hancock, A.,_ . 2 . 4,147, 148 Hartt, C. F., 98, 107, 120, 137, 188, 231, 232, 254 Haupt, ‘ - 294 Hayden, F. V., ‘3, 66, 120, 261, 264, 303, 304, 322 Helmersen, G. yon, 6 o F 319, 320 Herrick, C. L., . 3, 9, 121, 133, 189, 209, 254, 261, 304 323, 328 Hicks, H..,. 6 Hinde, G. J., 188, 201 Hisinger, W. von, 6 "200, 204, 276, 290, 303 Holl, H. B., . . : 0 4 4 . 6, 90 Huxley, 0. H., - F 0 : 6 1, 186 yvesoa Copa R 266 Jaekel, O., ; f 294 James, J. F., 5 5 O : . 3 8 James, U. P., . 3, 18, 19, 145, 188, 201, 205, 245 276, 281, 295 Joubin, E. . 0 5 5 0 , 1,147, 149 Kayser, E., 153, 211, 241, 242, 253, 259, 260, 285, 236, 290 301, 302 Keyes, C. R., 6 0 304, 323 Keyserling, A. von, 207, 317 King, C., 0 c 6 F 6 0 61 King, W., . 2,7, 10,11, 13, 14, 18, 20, 21, 22, 30,31, 33 34, 35, 36, 38, 40, 41, 43, 44, 45, 46, 48, 51, 5+, 55,57, 62 (63, 145, 147, 149, 156, 186, 200, 201, 204, 211, 245, 248 249, 251,'252, 267, 276, 279, 314, 317, 319, 320, 828, 339 Kleeden, K. F. von, 276, 303 Koninck, L. de, 7 211, 253, 267, 276, 301, 302, 303, 306 314, 317, 319, 321, 323, 325, 835, 334 Kyvotow, 6 a 5 0 0 - 310 Kutorga, S., . - 80, 82, 95, 101, 102, 103, 109, 110, 111, 112 118, 115, 116, 120, 128, 135, 136, 158, 160 Lacaze-Duthiers, é 5 é 16 Lamarck, J. P. B. A. de M. dey 0 5, 120, 121, 122, 145, 321 Linck, 0 5 : 6 . 321 Lindstrém, G., 33, 34, 36, 38, 201, 204, 241, 245, 274 Linnarsson, J. G. O., 86, 91, 94, 97, 98, 99, 101, 107, 108 Linne,C., . 6 6 145, 150, 204, 218 Marcou, J., 9 . D 187, 208, 322 Marcy,O., . . . S 4 5 9 284 Martin, W., : F o peat, Bel Matthew, G. F., 56, 58, 69, 81, 91, 93, 99, 101, 102, 103 105, 107, 187, 183, 231, 232, 233 Maurer, F., . 0 a 0 . F 259 McChesney, J. H., - 120, 187, 185, 194, 196, 261, 262, “322, 350 McCoy, F., . 55, 83, 129, 155, 158, 187, 200, 201, 203, 204 211, 233, 245, 253, 261, 269, 276, 280, 284, 290, 298, 303 314, 321 Meek, F.B., . 3, 33, 36, 56, 62, 64, 66, 90, 97, 101, 103, 120 127, 182, 135, 187, 188, 194, 196, 198, 201, 205, 208, 211 214, 215, 217, 245, 250, 253, 254, 261, 267, 269, 272, 276 281, 284, 290, 295, 303, 304, 309, 322, 328 Michaud, A. L. G., : 4 2 6 321 Mickwitz, A., : 337, 339 Miller, S. A., ‘3, 8, 138, 145, 188, 194, 196, 198, 201 202, 205, 208, 245, 272, 276, 281, 295, 323 Méller, V. von, 6 5 o 95, 96, 102 Miiller,Q.F., . 7 122, 145, 150 Morris, J., P ‘ 6 110, 135, 303 Morse, E. S., 0 6 5 0 : 0 8, ot Morton, L. G., 6 C 5 321 Minster, G. yon, 0 5 5 . 3it Munier-Chalmas, . 28, 298 INDEX. PAGEs Murchison, R. I., . 56, 227, 328 Nettelroth, H., 3, 146, ‘189, 193, 198, 201, 206, 209 211, 254, 277, 285, 290, 304, 328 Neumayr, M., . . A 2 301, 324 Newberry, J.S.,_ . D : . 9, 264, 266, 303, 322 Nicholson, H. A., 3, 33, 36, 120, 138, 145, 188, 192, 201 254, 285, 304, 328 Norwood, J. G., 303, 312, 321, 328, 332, 333 @hlert, D,P., . : 28, 158, 208, 209, 210, 233, 241, 243 250, 254, 261, 267, 269, 272, 277, 286, 287, 288, 289, 295 302, 310, 326, 333, 335 Oldham, R., . 2 5 - 7 : . 29 Orbigny, A. a’, 120, 128, 136, 138, 141, 158, 160,186, 214 217, 233, 234, 237, 245, 303, 321 Owen, D. D., : 2, 59, 187, 192, 200, 208, 225, 245 261, 284, 303, 321 Owen, R., . - ‘ n 2,16, 186 Pander, C. H., 80, 117, 118, 119, 141, 186, 192, 200, 221 233, 234, 235, 236, 237, 238, 250, 284, 295, 290, 2997, 295 Parkinson, J., 5 5 . 5 5 erAl Philips, J., 2, 6, 15, 201, 211, 245, 253, 256, 257, 261 269, 276, 284, 303 Pilsbry, H. A., 6 : 5 . 246 Poli, J. X., . > y 2 5 , 145, 147 Potiez, V. L. V-, 9 pil Poulson, C. A., 5 5 C 250 Pratten, H., 5 - 303, 312, 321, 328, 332, 333 Prout, H. A., 5 5 : 4 321 Quenstedt, F. A., 80, 109, 110, 200, 205, 211, 219 241, 245, 267, 301 Rafinesque, C.'8., 245, 246, 247, 248, 249, 250, 252 Ramsay, A. C., . 204 Rang, A.S., . 5 4 : 5 : - 321 Rathbun, R., . > : A 3, 120, 188, 304, 328 Reeve, L. A., F c . o 3 121 Retzius, A. J., . . . 145, 150 Rieman, P., 218 Rigaux, E., : 2 . ° : 5 - 241 Ringueberg, E. N.S., 5 6 3, 120, 146, 189, 204, 205 Romer, F., 6 - 2, 187, 205, 276, 290, 302 Rogers, H. D., O . 195, 201, 281, 284, 322 Rouault, M., o ‘ . 5 5 F 36, 241 Salter, J. W., 6, 36, 55, 56, 57, 58, 83, 84, 86, 107, 153 158, 187, 192, 196, 201, 204, 241, 245, 269, 274, 284, 322 Sandberger, G. and F., O . : - 2353 Safford, J. M., 6 5 183, 199, 200, 241, 341 Schauroth, K. F., . o 3 : - 145, 150 Schiel, 2 2 5 5 . 321 Schlotheim, E, von, 145, 155, 158, 186, 200, 202, 211 218, 233, 253, 267 Schnur, S., . 241, 253, 257, 259, 284, 30! Schmidt, Fr. 86, 290 Schuchert, C., 25, 88, 112 Schumacher, . 121, 122, 123 Seebach, K. von, 101 Semenow, P., ' : c : - 203 Shaler, N.S., . 187, 189, 192, 196, 198, 208, 233, 246 276, 251, 288, 295 Sharpe, D., 5 118, 138, 141, 248, 303 Shepard, C U., 5 5 5 a 321 Shumard, B. F., 3, 120, 145, 187, 303, 319, 321, 322 Simpson,G.B., . : 189, 209, 304 Sowerby, J., "120, 121, 122, 150, 155, 158, 192, 203 (204, 211, 227, 245, 253, 276, 284, 290, 317, 321, 328 INDEX. 357 PAGE. PAGE. Sowerby, J.deC., . : 6 O 6 121, 276 | Walcott, C. D., 3, 9, 56, 57, 58, 66, 67, 68, 69, 70 Spencer, J. W., O : 5 : 6 . 146 71, 72, 75, 78, 91, 92, 97, 98, 99, 100, 101, 102, 103, 104 St. John, O, O 6 o O . 145, 264, 314 105, 106, 107, 111, 113, 114, 116, 117, 121, 137, 146, 155 Stevens, . 6 2 : : o Q 303 188, 189, 193, 194, 198, 206, 211, 230, 281, 232, 241, 243 Stobeus, K., 145 246, 254, 269, 278, 285, 290, 304, 314, 328, 332 Stoliczka, F., : . : : 29 | Waldheim, G. F. de, 191, 214, 215, 264, 266, 275 Swallow, G. C., 187, 208, 264, 284, 322, 328 | Wenjukoff, P., C . ° : . . 259 Swinton, F. S., : . 218 | White, C. A., 3, 90, 98, 101, 120, 121, 145, 146, 187, 188, 192 Tschernyschew, Th , 241, 243 196, 198, 201, 206, 208, 209, 211, 245, 253, 264,277, 281 Trautschold, H. von, : 0 214 285, 304, 314, 322, 323 Tryon, G. W., : . : . . . 246 | Whiteaves, J. F., 8, 27, 40, 44, 45, 46, 56,113, 115 Ulrich, E. O., 24, 25, 27, 32, 53, 87, 88, 89, 112, 120 244, 293, 314 138, 148, 188, 194, 295 | Whitfeld, R. P., 3, 11, 36, 48, 57, 59, 61, 62, 66 Ure, D., pe . i 303, 321 69, 120, 187, 188, 189, 195, 198, 206, 208, 209, 211, 218, 230 Vanuxem, L., 2, 120, 186, 205, 211, 253, 257, 258 233, 239, 240, 245, 246, 253, 254, 269, 277, 281, 285, 304 276, 281, 284, 290, 303, 328 310, 311, 322, 323 . Wilckens,C. F., . a * a ° 276, 279 Verneuil, E. de, - 110, 111, 141, 151, 191, 200, 201, 204, 214 Williams, H. S., 2 ; : ; E 3 219, 233, 238, 215, 253, 256, 264, 266, 269, 276, 280, 288 Winchell, A., 3, 62, G4, 120, 145, 152, 187, 188 297, 298, 300, 301, 308, 317, 319, 321, 323, 323, 328, 333 208, 211, 253, 284, 304, 314, 322, 328 Verworn, : : : : : 155 | Winchell, N. H.,, 3, 59, 62, 145, 188, 194, 195, 206, 281 Volborth, A. von 3 3 is 73, 82, 83 Woodward, S. P., : : 4 ; : 56 Waagen, W , _ 23, 29, 30, S4, 89, 90, 94, 95, 118, 147 | Worthen, A. W., 3, 36, 62, 64, 120, 121, 188, 253, 261 154, 210, 214, 215, 216, 217, 239, 254, 256, 261, 262, 263 276, 281, 290, 303, 309, 322, 328 264, 265, 267, 268, 304, 306, 307, 308, 310, 313, 316, 317 | Wynne, : . 5 : o 6 5 29 319, 320, 324, 325, 326, 330, 331, 332 | Yandell, L. P., 6 6 0 5 oath Waller, . 5 : c 5 3 - 145 | Young,J., . 6 5 3 5 5 307 Warth, H., 30 | Zittel, K. A. yon, 6 5 . 124, 272, 295, 308 Walch, J. E. J., 321 | Zugmayer, H., ‘ . . = . 5 298 IJ. RecisteR OF GENERA. (Names in italics are synonyms; figures in FULL-FACE type denote place of description.) PAGE. PAGE. Acritis, a : : Z 2 . 80, 82 | Brachyprion, 220, 288, 289, 292 Acrothele, 70, 98, 99, 100, 102, 103, 108, 113, 114, 167, 168 | Cadomella, 298 Acrothele? . : 9 0 6 : . 101 | Camarella, : r < s 234 Acrotreta, 68, 93, 95, 96, 99, 100, 101, 103, 104, 105 | Camarella, . 6 : D F 5 269 106, 108, 109, 113, 114, 166, 167, 168 Cardinocrania, 30, 147, 154 Acrotreta, : 95, 105 | Chonetella, : - 0 307, 313 Amboceelia, 92 | Chonetes, . 191, 230, 280, 301, 303, 305, 306, 307 Amphiclina, 302 308, 309, 310, 311, 312, 313, 316, 320 Amphistrophia, 292 | Chonetes, 314, 317 Ancistrocrania, . . 146 | Chonetina, 307, 310 Anomia, . 145,211, 321 | Choniopora, 145, 150 Anomites, 5 233, 276, 321 | Chonostrophia, . 307, 310, 311 Anoplia, ; 309 | Chonotreta, . a 96, 104, 167, 168 Anoplotheca, 6 E ° D : . 220, 302 | Chonopectus, 307, 312 Arbusculites, : - : : 0 q 321 | Choristites, . 214, 216, 264 Arca, . 321 | Christiania, - 298 Atrypa, 207, 298 | Clavagella, : 6 ‘ 321, 333 Atrypa, 187, 200, 269 | Clitambonites, 21S, 219, 230, 231, 232, 233, 234 Aulonotreta, - 82, 337 236, 237, 239, 240, 243, 340 - Aulonotreta, 6 - 80 | Conchites, F 5 2 276 Aulosteges, . 0 b : 316, 319, 330 | Conocephalites, . 30 Aulosteges, ; 5 : . 3814 | (Conradia,) 0 5 ‘ 5 . 5 39 Avicula, o F 66 Crania, 1, 108, 122, 144, 146, 147, 149, 150, 151, 152 Barroisella, 1, 14, G2, 64, 85, 103, 164 153, 154, 155, 156, 157, 158, 169, 170 Billingsella, . 0 5 229, 231, 232 | Crania, 9 : 4 6 9 110, 314 Billingsia, 0 5 0 . : - 75, 76 | Crania(Pseudocrania) . 6 0 3 . 5 ae Bilobites, 5 5 204, 219, 223, 229 | Craniella, 6 . 7 ‘ 0 ° 153, 170 368 PAGE. Craniolites, 5 5 . ; ° 5 - 145 Craniops, : e o fF A 6 155, 159 Craniscus, ° . . ° ° 146 Criopoderma, . , 145 Criopus, 145, 147 Cyclonema, 0 , 4 A 145 Dalmanella, 6 : 205, 218, 219, 220, 223, 229 Dawidsonella, A“ 4 5 5 28 Davidsonia, 5 . . 5 O 279, 301, 302 Daviesiella, . 317 Delthyvris, F 186, 187, 200, 201, 204 Derbya, 219, 256, 258, 261, 262, 263, 265, 263 347 Derbyia, . 261 Dicellomus, 66, 68, R, 73 Dicalosia, 204 Dicraniscus, . 5 270 Dicraniscus, ' , g 6 2 269 Dignomia, 2, 14, 15, 2, 163, 164 Dinobolus, Q 23, 28, 30, 31, 34, 36, 89, 46,47, 48 50, 51, 52, 53, 5L, 55, $1, 84, 139, 142, 165, 176 Dinobolus, .36, 44 Dinorthis, 2 195 3, 222, 227, 229 Discina, 0 « 120, 121, 124, 149, 150, 169 Discina, ] 29, 87, 9), 93, 107, 120, 122, 124, 129, 132, 155 Discinisca, 120, 123, 124, 125, 130, 131, 149, 169 (Discinocaris?,) . O . 142 Discinolepis, 29,90, 110, 141 Discinopsis, 103, 105, 106, 167, 168 Douvillina, eC 236, 288 Elkania, 51, 52, 54, 69, 75,76, 77,78, 165 Enteletes, . 214, 215, 216, 217, 226, 229 Etheridgina, . 335 Geinitzia, 104 Glossina, 0 15, 16 Glottidia, 2, uy, 15, 63, 163, 164 Gonambonites, 219, 236, 237 Gonambonites, 233 Gotlandia, 33 Gryphites, p 6 A 321 Hebertella, 198,222) 229 Helmersenia, 117, 118, 119 Hemipronites, 3 236, 238, 239, 250 Hemipronites, m D . .233, 239, 245, a 254, 261 Hemithyris, 269 Heterorthis, O02, 223, 229 Hipparionyx, aay 258, 265 Hysterolithes, 186, 21], 213 Hysterolithus, : 186, 213 Iphidea, . 96, 97, 166, 167, 168 Iphidea (? 2), * 90 Kayserella, 5 s 259 Keyserlingia, 117, 118, 119, 141 Klitambonites, 233, 235, 236 Koninckella, 298, 302 KKoninckina, 301, 302 * Kutorgina, 90, 91, 92, 93, 4, 95, 96, 97, 114, 140 166, 168, 183 Lakhmina, 28, 30, 35, 46, 47, 48, 52,58, 89 Ligulops, . i é 5 5 5 = > 2h) Lindstremella, . 120,134, 140 Lingula, 1, 2,5, 6, 8, 10, li, 4, 15, 16,18, 21, 22, 23,24, 25 27, 28, 32, 48, 49, 50, 51, 52, 54, 56, 57, 58, 59, 61, 62, 63 64, 65, 109, 161, 162, 163, 164, 165 Lingula, 2, 18, 36, 55, 56, 59, 62,66, 98 INDEX. PAGE. Lingula? 5 5 56,62, 86 Lingula (Glottidia), 62 Lingularius. 0 5 2 5 A 2 Lingulasma, RA, 25, 27, 30, 32, 46, 47,48 49, 50 51, 52, 53, 78, 81, 163 Lingulella, 6, 7, 8, 19, 52, 55, 56, 57, 58,59, 61 62, 64, 69, 92,162, 165 Lingulella (Dignomia?), . 6 . 56 Lingulepis, - n 4 6, 59, 61,81, 163 Lingulepis, : . 56 Lingulops, 8, 18, 19, 20, 21, 22, 23, “94, 25, 30,32, 46 47, 48, 49, 51, 52, 54, 55, 156, a6h, 165 Leptena, 192, 220, 236, a 276, 279, 280, 282, 286 293, 296, 299 Leptena, 47, 187, 196, 225, 253, 261, 281, 284, 314, 317 321, 328 Leptenalosia, - olf Leptenisea, . 279,300, 301 Leptznulopsis, . 294 Leptagonia, 276, 280 Leptella, . 293, 294, 298 Leptobolus, 73, 74, 75, 79,165, 167 Leptoceelia, 220 Leptostrophia, 288 Tima, . A . > C 5 RA! Linnarssonia, 68, 69, 70, 106, LO7, 109, 113, 167, 163 Marginifera, 330, 331, 332 Meekella, 219, 259, 262, 263, 264, 265, 266, 268 Mesotreta, 105, 109, 111 Mickwitzia, o 5 . 80. 86 Mimulus, 270, 272, 273, 274 Monobolina, 9 : 0 80,83, 8st Monomerella, S 22, 23, 25, 29, 30, 31, 34, 35, 36, 37, 39 40, 41, 43, 46, 50, 53, 164, 176 Mystrophora, . 241 Mytilus, i $ 5 - 321 Neobolus, 1, 29, 30, 80, 84, £9,118, 163 Numulus, 5 : P 6 - 145 Obolella, 2, 575 83, 61, 64, 66, 63, 69, 70, 72, 73,75, 7 77, 78, 8), aL 83, 85, $8, 89, 91, 108, 140, 164, 165, 167, 339 Obolella, - 56, 75, 90, 107 Obolella 2, - 8 Obolellina, A 5 : 3 : 06, 44 Obolus, 51, 52, 56, 72,77, 80, 81, $2, 83, 84, 86,108, 13 140, 165, 183, 337, 339 Obolus, 36, 44, 66, 83, 90, 98, 117, 118, 119 Obolus ?, : - 83, 86 Obolus [Trimerella}, 5 . f 27736 hlertella, 120, 133, 144, 168, 169 Olenus (?), 30 Orbicella, é “118, 119, 1B, 141 Orbicuxa, 36, 57, 66, 118, 120, 121, 138, 142, 145, 159 155, 158 Orbicularius, ; : : . a : - 1 Orbiculoidea, 120, 121, 124, 125, 128, 129, 132, 133 135, 136, 187, 138, 140, 144, 150, 158, 160, 166, 168, 169 Orthambonites, 3 236 Orthambonites, 186, 192 Orthidium, . 5 3 5 5 . 244 Orthis, 92, 185, 186, 191, 192, 193, 194, 197, 201 203, 210, 215, 216, 217, 218, 219, 220, 221, 224, 225, 227 228, 229, 230, 231, 232, 236, 242, 243, 252, 257, 298, 301 Orthis, . 80, 211, 230, 231, 233, 241, 244, 245, 253, 259 261, 264, 267, 269, 276, 281, 284, 314, 319 INDEX. PAGE. Orthis (Schizophoria), Q 5 5 a PIG Orthisina, 98, 219, 230, 232, 234, 237, 240 Orthisina, . 230, 288, 253, 261, 264, 267 Orthostrophia, . : ~ 199, 223, 229 Orthothetes, 218, 219, 220, 249, 253, 255, 256, 257 | 258, 261, 262, 268, 295 Orthothriz, : 0 , es : 3 314 | Orthotichia, : 5 0 ‘ 4 218, 226, 229 Ostracites, 145 Palacmea?, °*. 0 138 Paleocrania, . 0 a : : 5 152, 159 Patella, 115, 155, 158 Patellites, 155, 158 Paterula, . . 78, 165, 166, 168 Pentamerus, . 234 Pharetra, . F 6 F 2 Pholidops, 1, 151, 152, 155, 156, 157, 158, 170 Pholidostrophia, 287 Pinna, rs - ol Plesiomys, . 196,222; 229 Platystrophia, 4 200, 202, 223, 229 Plectambonites, ‘220, 236, 250, 293, 294, 295, 296 297, 298, 299, 300, 302, 305, 306 Plectambonites, . 276, 284 Plectorthis, . 194, 221, 229 Pleurotomaria, . 6 148 Plicatula, 264 Polyteechia, 5 238, 239 Porambonites, 217, 219 Porambonites, 136, 200 Proboscidella, 333 Producta, . 269, 216, 321 Productella, . : ‘301, 315, 818, 325, 328, 329, 332 Productella, A : . 314 Productus, 185, 5 G0, 9363, 280, 297, 301, 307, 316 318, 319, 320, 321, 323, 325, 330, 331, 332, 334, 335, 336 Productus, 186, 276, 314, 317, 328, 333 Pronites, O 219, 286, 237 Pronites, 233 Protonia, F 6 321 Protorthis, 219, 231, 232, 238 Pseudocrania, . 250,152; 159 Pyzis, 6 o P 5 BpAl Rafinesquina, 5 281, 282, 286, 289, 298 Rhinobolus, . 22, 39, 31, 32, 42, 43, 44, 45, 46, 50,52, 53 Rhipidomella, 208, 210, 212, 219, 220, 224, 229, 254 Rhipidomella, : 214 Rhipidomys, 208, 210 Rhynobolus, 44, 46 Richthofenia, . 154 Remerella, 0 120, 137 Scenidium, 9 , 218, RAL, 242, 243, 259 Schizambon, 98, 108, 109, 111, 113, 114, 116, 167,168, 169 Schizobolus, 79, $7, 89, 140, 165, 166, 168 Schizocrania, “43, 89, 131, 132, 140, 142, 144, 168, 169 Schizopholis, r 29, 93, 94, 95, 96, 166, 168 Schizophoria, 211, 212, 213, 214, 219, 226, 229, 343 PAGE. Schizotreta, 116, 120, 125, 128, 13!, 135, 126, 140 144, 158, 168 Schmidtia, 73, 80, $3, 165, 167, 337 Siphonotreta, 79, 94, 99, 108, 109, 110, 111, 112, 114, 115, 119 140, 166, 167, 168 Skenidium, . . ‘ . 241, 247 Spirifer, : 0 B ; . 201 Spirifer, 186, 187, 200, 201, 204, 214, 261, 269 Spirifera, « 201,211, 253; 272 Spondylobolus, {1, 80, 85, 108, 164 Spondylus, 5 5 314 Stenoschisma, 7 5 O 234 Stenotheca, s. g. Parmorphorella, 6 6 137 Streptis, 270, 271, 273, 274 Streptis, 6 0 O * 6 5 . 272 Streptorhynchus, . . 219, 257, 260, 262, 265, 267, 268 Streptorhynchus, 47, 245, 258, 254, 259, 261, 264 Stricklandinia, . 6 6 6 220 Strophalosia, 314, 315, 316, 319, 320, 330, 335 Strophalosia, . D a : O 319, 328 Stropheodonta, 220, 258, 282, 284, 286, 287, 288, 289 292, 307, 311 Strophodonta, P 47, 186, 185, 284, 285 Strophomena, 197, 220, 245, 246, 248, 250, 251, 252 255, 262, 279, 282, 236,291, 311 Strophomena, . 47, 187, 196, 253, 276, 277, 281, 284 285, 286, 314, 321, 328 Strophomenes, , . 245, 246, 248, 252 Strophonella, 136, 191, 220, 279, 282, 289, 290 291, 292, 296, 311 Syntrielasma, 214, 216 Terebratala, 5 é c 5 16 Terebratula, 110, 186, 200, 204, 211, 214, 269, 321, 324 Terebratulina, . F F 5 5 16 Terebratulites, 9 5 200, 211, 25%, 267 Thecidium, . 6 0 16,° 28 Thecospira, 302 Tomasina, ° G : . , . 65 Trematis, £7, 89, 92, 118, 131, 132, 138, 140, 141, 168, 169 Trematis, 36, 87, 142 Trematis 2, 90 - Trematis Uschieccrontal 142 Trematospira?, 187 Tridacna, 321 Trimerella, 1, 21, ‘25, 28, 29, 30, 31, 33, 35, 31, 39, 40, 42, 43, 44 46, 47, 48, 49, 50, 51, 52, 53, 55, 113, 156, 163, 164, 165 Trimerella, 44 Trimerella?, 6 r Q 44 Triplecia, 269, 270, 271, 273, 274 Triplesia, 0 269 Tropidoleptus, 207, 220 Tubifex, 8 Ungula, . 80 Ungulites . . 5 80 Volborthia, 93, 95, 96, 98, 102, 166, 167, 168 Waagenia, 239 Waagenella, P 239 Waldheimia, . 3 24 359 360 INDEX. III. Reaister or Spectres. (Names in italics are synonyms; figures in rULL-rAce type after new species denote the place of description.) Acritis antiquissima, von Bichwald, . Acrothele coriacea, Linnarsson, FAG dichotoma, Walcott, A. granulata, Linnarsson, A. Matthewi, Hartt, A. subsidua, White, Acrotreta attenuata, Meek, A. Babel, Barrande, A Baileyi, Matthew, ? costata, Davidson, disparirugata, Kutorga, gemma, Billings, 2 Gulielmi, Matthew, Nicholsoni, Davidson, pyxidicula, White, recurva, Kutorga socialis, von Seebach, . subconica, Meek, BY subsidua, White, nomic biloba, Linné, craniolaris, Linne, Anomites productus, Martin, semireticulatus, Martin, Atrypa ? apiculata, Salter, cuspidata, Wall, extans, Emmons, incerta, Davidson, nucleus, Hall, (Triplecia) apiculata, Salter, (T.) incerta, Davidson, ulonotreta polita, Kutorga, sculpta, Kutorga, . r ulosteges Dalhousii, Davidson, guadalupensis, Shumard, Medlicottianus, Waagen, spondyliformis, White and St. bona variabilis, yon Helmersen, Wangenheimi, de Verneuil, Avicula? desquamata, Hall, Barroisella subspatulata, Meek and Worthen, Brachy prion Leda, Billings, B. geniculatum, Shaler, B. ventricosum, Shaler, Camarella calcifera, Billings, . Cardinocrania indica, Waagen, Christiania subquadrata, sp. noy., Chonetella nasuta, Waagen, Chonetes Antiopia, Billings, . Canadensis, Billings, complanata, Hall, cornuta, Hall, coronata, Conrad, Dawsoni, Billings, Fischeri, Norwood and Pr atten, glabra, Geinitz, levis, Keyes, lepida, Hall, lineata, Vanuwem, mesoloba, Norwood and Pi atten minima, Sowerby, MRABRPRRERE EES S ~ -PRAPPE PEP PRR DD ESQ Gaegaaeoae PAGE. . 99, 100, 99, 100, 100, 99, 102, 102, 103, 102, 103, 103, 95, 101, 103, 80, 316, 31g, 12, 63, . B51 32 | 100 | 103 | 100 | 101 101 103 105 103 104 104 106 105 103 103 102 113 104 100 204 | 150 325 325 270 270 270 | 270 270 271 271 82 82 320 | 320 320 | 320 320 | 319 67 | 164 | 288 | 288 | 288 ami | 154 313 | 308 308 dll 308 312 311 312 306 | 306 306 306 310 | 294 | Chonetes mucronata, Hall, 4 C. muricata, Hall, (OF Nova-scotica, Hall, C. papilionacea, Phillips, as polita, McCoy, Cc. tenuistriata, Hall, C. undulata, Hall, Cc. Verneuiliana, Norwood and aaion. Chonetina Artiensis, Krotow, Chonostrophia Helderbergia, sp. noy. Clitambonites adscendens, Pander, Conchites rhomboidalis, Wilckens, Conchyliolithus anomites resupinata, Martin, Conotreta Rusti, Walcott, Crania agaricina, sp. noy , anomala, Muller, antiquissima, yon Bichyalds Brattensburgensis, Ietzius, columbiana, Walcott, eraniolaris, Linne, craniolaris, McCoy, fayincola, sp. noy., granosa, sp. Noy Ignabergensis, Retzius multipunctata, Miller, parallela, Ulrich, Parisiensis, Defrance, percarinata, Ulrich, pulchella, sp. nov., radicans, Winchell, radiosa, Gould, scabiosa, Hall, . Schaurothi, Geinitz, Sedgwicki, Lewis, setifera, Hall, 2 . setigera, Hall, . 6 A 5 socialis, Ulrich, striata, Schumacher, Trentonensis, Hall, tripartita, Minster, (Craniella) Hamiltoniz, Hall, (Pseudocrania) anomala, Winchell, C. (P.) divaricata, McCoy, Craniella Hamiltonix, Hall, (6) Meduanensis, @hlert, Cc. Ulvichi, sp. noy., Dayidsonia Boucharaiaias de Koninck, D. Verneuili, Bouchard, . Davidsonella linguloides, Waagen, D. (= Lakhmina) linguloides, Waagen, Derbya afiinis, sp. nov., Bennetti, sp. noy., biloba, sp. noy., Broadheadi, sp. noy., Correana, Derby, . costatula, sp. nov., crassa, Meek and Hayden, grandis, Waagen, Keokuk, Hail, : regularis, Waagen, . 4 gage ageaesqgneagesanaaaaacoeaae SENS ISIS ISVS) ISHS) ~ PAGE. 306 316 308 307 306 308 308 310 4 310 311, 353 235 279 211 - 104 1380 1i7 150, 148, 149, 153 es 349, 350 263, 348 3350 263, 346, 347 263 - 346 263 - 262 262 262 INDEX. PAGE. Derbya robusta, Hall, 0 0 262 D. ruginosa, sp. noy., . 346 Dinobolus Bohemicus, Barrande, 39 D. Brimonti, Rowault, . 9 39 D. Canadensis, Billings, é 2 3 39 D. Conradi, Hall, . $3, 39, 40, 42, 43,175, 176 D. Hicksi, Davidson, . 39 D. magnificus, Billings, . 5 BY) bD. parvus, Whitjield, . 5 a 39, 40 D. Schmidti, Davidson and King, 39, 40 D. transversus, Salter, 39, 40 D. Woodwardi, Salter, 39, 40 Discina acadica, Hartt, a 137 D. ampla, Hall, 125, 127, 1380 D.? Balcletchensis, Davidson, 5 79 D. Bohemica, Barrande, 127 D. Caerfaiensis, Hicks, 137 D. clara, Spencer, . 125 D. Conradi, Hall, 125, 130 D. discus, Hall, 125, 132 D. Doria, Hall, 125 D. grandis, Vanuxem, 125, 136 D. humilis, Hall, a 125 Dz. Herzeri, sp. nov., Ps 127, 131 D. intermedia, Barrande, - 3 135 D. inutilis, Hall, 5 Iby/ D. lamellosa, Broderip, 122, 123 D. Lodensis, Hall, 5 cq 125 D. Meotis, Barrande, 6 3 . 127 D. Manhattanensis, Meek and Worthen, 5 es D. marginalis, Whitfield, 125, 127 D. media, Hall, 125, 133 D. minuta, Hall, 125, 131 D. Morrisi, Davidson, 5 1b) D. Newberryi, Hall, 125, 130 D. nitida, Phillips, 125, 126, 131 D. ostreoides, Lamarck, 121, ~122 D. pileolus, Hicks, 5 5 UBYy D. pleurites, Meek, f 125, 131, 132 D. Randalli, Hall, ms O . 125 Jo). reversa, Barrande, 133, 135 D. rugata, Barrande, 0 Ibs) D. secedens, Barrande . 101 D. striata, Schumacher, 122, 123, 125 D. striata, Sowerby, 122 D. tarda, Barrande, 135 D. tenuilamellata, Hall, 125 D. truncata. Hall, 87 D. (éhlertella) pleurites. o 140 Discinisca lamellosa, Broderip, 131, 133, 136 Discinolepis granulata, Waagen, z 90 Discinopsis Gulielmi, Matthew, 106 Douvillina Dutertrii, Murchison, 289 Elkania desiderata, Billings, 77 Enteletes ferrugineus, Waagen, . 6 216 E. hemiplicatus, Hall, , 217, 226 E. Lamarcki, Fischer de Waldheim, 214, 215, 22 E. pentameroides, Waagen, 216 Glottidia Audebardi, Broderip, 8 G. Palmeri, Dall, 4, 3 Gonambonites lata, Pander, 237 Hemipronites alta, Pander, 238 H. Americana, Whitfield, 3 239 A. apicalis, Whitfield, 239, 240 planumbona, Hall, 247, 250, 251 rhomboidalis, Wilckens, 250, 279, 280, 282, 286, 287, 296 rugosa, Hisinger, semiovalis, McCoy, sordida, Billings, subquadrata, Hall, tenuicincta, McCoy, transversalis, Dalman, unicostata, Meek and Worthen, Waltoni, Davidson, PAGE. Hemipronites nutans, James, 251, 345 H. spherica, Pander, 238 He tumida, Pander, 238 Hipparionyx consimilaris, Vanuxem, 258 ie consimilis, Vanuxem : 258 H. proximus, Vanuxem, 257, 258, 259 ie similaris, Vanuxem 5 258 Iphidea bella, Billings, Oy, 3 I. ornatella, Linnarsson, 97, 98 I. (22) sculptilis, Meek, ‘ 94, 97 Kutorgina cingulata, Billings, 67, 91, 92, 93,94, 95 K. cingulata var. pusilla, Linnarsson, 94 Ke Labradorica, Billings, 92, 94 Ix. Latourensis, Matthew, 92, 95, 94,95, 233 K. minutissima, Halland Whitfield, 94, 7 K. pannula, White, 92,94, 95 K. Prospectensis, Walcott, Gp te K. (2?) pterineoides, Matthew, . 94 K. sculptilis, Meek, 92, 94 K. Whitfieldi, Walcott, 92, 94 Lakhmina linguloides, Waagen, 29 Leptena enigma, de Verneuil, = “ . 300 L. alternata, Conrad, 248, 280, 282, 283 L alternistriata. Hall, 282 L analoga, Phillips, 279 L asella, de Verneuil, 288 DL. caudata, Schnur, 287 L concava, Hall, 300 L convexa, Pander, 297 L decipiens, Billings, 294, 298 L deltoidea, Conrad, 282, 283 L demissa, Conrad, . 286 L. depressa, Sowerby, 250, 279 L euglypha, Dalman, . 279, 296 L Dutertrit, Murchison, 288 L Sasciata, Hall, 282 L Jilitexta, Hall, 251 L incrassata, Hall (Saffor a), 282 L liasina, Bouchard, 298 D. Dlandeiloensis, Davidson, 294 L. Moorei, Davidson. 298 L multirugata, McCoy, 279 L. nodulosa, Phillips, ; 279 L.? nucleatu, Hall, . . 308, 309 L oblonga, de Verneuil, 300 L. obscura, Hall, 283 L plicotis, McCoy, 279 L L L L L L L L. L L L eptenisca adnascens, sp. nov., L concava, Hall, L. tangens, sp. noy., Leptznulopsis simplex, Haupt, Leptobolus insignis, Hall, L. lepis, Hall, L. _ occidens, Hall, - 29 279 293, 298 299, 300 2 - 300 279, 296, 299 282 . 283 301, 352 301 301, 352 294 C 73, 74 73,74, 75 73 362 PAGE. Lindstromella aspidium, sp. nov., 134, 178 Lingula acuminata, Conrad, 5 L. sequalis, Hall, , 9 ibe albida, 13, 14 I. alweata, Hall, 14, 15 10j, ampla, Owen, 6 L. anatina, Lamarck, 4, 5, 6, 7, ‘3, 10, i, 15, “W7, 21, 22 32, 49, 54, 55,57, 60 L. attenuata, Sowerby, 6,8, 15 L. Canadensis, Billings, 2s, 27 L. centrilineata, Hall, 15 L. compta. sp. nov. : 171 L. Covingtonensis, Hall and Whitfield, 8 DL, Criei, Davidson, ; : - 65 L. crumena, Phillips, 4 . . 5, 15 L. cuneata, Conrad, 6,12, 15 L. Daphne, Billings, 6 L. Davidsoni, Barrande, 64 Jp, Davisi, McCoy, . G 6 A 57 L. densa, Hall, a 3 5 9,15, 171 L. Delia, Hall, 0 9 6 15 L. distincta, Barrande, 18 L. Elderi, Whitfield, 9, 11,12, 48 L. epimia, Barrande, . . 18 DL. Feistmanteli, Barrande, : 68 L. flabellula, sp. noy., 6,15, 172 granulata, Phillips, é 15 Py Hawkii, Rouault, r 9 5 5 6, 15 insons, Barrande, 64 Iowensis, Owen, F 5 : 8 lamellata, Hall, 10, 12, 16,18, 48 Leena, Hall, . 6 . 9 0 5 6 ? Leseueri, Rouault, 7,9, 14, 63, 65, 164 Lewisi, Sowerby, 10 linguata, sp. noy., 173 Matthewi, Hartt, D 100 Melie, Hall, LOM 2 membranacea, A. Winchell, 64 Mosia, Hall, 2 5 : 6 Norwoodi, James, ‘ r : . 8, 19 paliformis, Hall, 59, 64 paracletus, sp. noy. 40, 12, 172 perovata, Hall, 6 petalon, Hicks, 6 5 pinniformis, Owen, A 4 : 59 2 polita, Hall, 6 : ‘4 . 67, 72 prima (Conrad), Hall, 0 69 Procteri, Ulrich, 10,12, 15 plumbea, Salter, . : . 83 punctata, Hall, 10, 11,12, 15,17, 48 pygma, Salter, 6 pyramidata, Stimpson, 8 o quadrata, Hall, . 5 < : 14 riciniformis, Hall, 4 5 4 , 6, 8 Rouaulti, Saléer, 6 6 scotica, Davidson, eo 16 scutella, sp. nov., V1 spathata, Hall, 18 5 spatiosa, Hall, 6 squamosa, Holl, 6 subspatulata, Meek and Woe: 63 bj taniola, sp. nov., 18, 173 2 tenuigranulata, McCoy, 6 18, 27, Vanhornii, Miller, C 6 . r o 8 PRPS PE PR Ee eR RP INDEX. PAGE. Lingula Waverliensis, Herrick, ; : 9 it Whitii, Walcott, 9,11,12, 48 L. Winona, Hall, 6 L. zebra, Barrande, , P 7 18 L. (Glottidia) Audebardi, Broderion : . 8, 162 Lingulasma Schucherti, Ulrich, 24, 27 Lingulella celata, Hall, 57,58, 69 L Cincinnatiensis, Hall and Whitfield, - O59 L. Dayisi, McCoy, 56, 57 L. Dawsoni, Matthew, - 58 L. Ella, Hall and Whitjield, 57, 58 L. ferruginea, Salter, 58 L. Granvyillensis, Walcott, A 58 L. Towensis, Owen, 8,14, 59 L. lepis, Salter, 58 Lingulepis antiqua, Hall, 61 L. cuneata, Whitfield, 61 L. Ella, Hall and Whitfield, 61 L. Mera, Hall and Whitfield, 61 L. minima, Whitfield, 62 L. ? minuta, Hall and Whitfield, 61 L. Morsii, VN. H. Winchell, 62 L. perattenuata, Whitfield, 5 61 L. pinniformis, Owen, A 2 c 60, 61 Lingulops Granti, sp. noy. 19, 20, 21, 23, 32, 50, 173 L. Norwoodi, James, - 20, 21, 23,32, 50, 173 L. Whitfieldi, Hal, 18, 19, 20, 21, 23, 26, 32,50, 173 Linnarssonia pretiosa, Billings, . - 109 L. misera, Billings, 107, 108, 109 L. sagittalis, Salter, 108, 109 L. Taconica, Walcott, ” 106, 107, 108, 109 L. transyersa, Hartt, 107, 108, 109 Marginifera ornata, Waagen, 5 331 M. typica, Waagen, 3 330, 331 Mickwitzia monilifera, Linnarsson, 86 Microdon (Cypricardella) bellistriata, Gonna) 148 Mimulus contrarius, Barrande, . C 273 M. Waldronensis, Miller and yen 273, 274 Monomerella Egani,sp.noy., . 42,175 M. Greenii, sp. noy. 42, 45, 62,174, 175 M. Kingi, sp. nov. 42, 174 M. Lindstremi, Davidson aa King, : 41 M. orbicularis, Billings, = 41 M. Ortoni, sp. nov. 4 42,438,175 M. ovata, Whiteaves, 3 3 : 42, 54 M. prisca, Billings, 41,42, 43 M. Walmstedti, Davidson and Rang) 41 Neobolus Warthi, Waagen, 0 : St N. Wynnii, Waagen, A O 84 Numulus Brattensburgensis, Sionenes 150 Obolella atlantica, Walcott, ‘ : 69 0.2 ambigua, Walcott, .- F . O 69, 78 oO. Belti, Davidson, 68 0. celata, Hall, . 69 oO chromatica, Billings, 66, 67, “63, 69, 70, 2p, 73, 2, 76 78, 91 oO. cingulata, Billings, 69, 91 oO. Circe, Billings, 4 63, 69 oO. crassa, Hall, 67, 68, 69, 70, 71, 72,75, 78 0. desiderata, Billings, . . 57,69, 75 0. desquamata, Hall, 68 0.2? discoidea, Hall and Whitfield, 9 . 69 oO. gemma, Billings, 68, 69,70, 71 0.2? Ida, Billings, . a ; 0 69 INDEX. PAGE. Obolella maculata, Hicks, . 0 0 : 68, 109 0. misera, Billings, a 5 9 . 69 oO. nana, Meek and Hayden, : : 69, 70 oO. nilida, Ford, . o ° 0 69, 70 oO. Phillipsi, Hold, F 0 94 oO. polita, Hall, E 5 ‘4 68, 69, 70, PR, 73, 83 0. pretiosa, Billings, . : 2 @ 70 oO. Sabrine, Callaway, . F ° 68, 103 0. sagittalis, Salter, “ ‘ GS el O75 eL08, 0. transversa, Hartt, 5 : : 70, 107 Obolus advena, Barrande, , F 9 68, 69 oO. antiquissimus, von Eichwald, 3 , 5 «6 GY oO. Apollinis, von Hichwald, F 51, 80, 82, 339 0. Appolinus, Owen, 2 0.2? Bohemicus, Barrande, * 101 0.2 complexus, Barrande, 5 : d 68, 73 O. ingricus, von Eichwald, 82 0. Labradoricus, Billings, : 5 o 6 0. pulcher, Matthew, 6 D 6 81, 183 oO. Quenstedti, Mickwitz, 339 oO. siluricus, von Hichwald, é 9 : 82 Géhlertella pleurites, Meek, . D o o JL, Gh) Orbicula antiquissima, yon Eichwald, . . 118,119, 140 0. Buchi, de Verneuil, . 5 0 5 te aly 0. celata, Hall, 69 0. crassa, Hall, 2 0. deformata, Hall, F 5 6 d 150 0. Morrisi, Davidson, . ; 128, 129, 130, 160 0. norvegica, Sowerby, 121 oO. norvegica, Lamarck, 122 0. punctata, Sowerby, 140 O. reversa, de Verneuil, 118 0.2 squamiformis, Hall, 5 j . 159 0. terminalis, Emmons, 140 Orbiculoidea, sp. ? Meek, 5 z; 3 = 127 0. conica, Dwight, 0 + 116,124) 126,129; 185 oO. Davidsoni, d'Orbigny, . 0 E P 160 O. Forbesi, Davidson, . 116, 125, 126, 129, 135, 160 0. grandis, Vanuxem, 6 . 133 oO. Herzeri, sp. noy. : 6 178 oO. Morrisi, Davidson, A : 5 1338, 160 oO. Newberryi, Hall, 130 oO. nitida, Phillips, 136 O. numulus, sp. noy. 178 oO. Randalli, Hall, p c 6 133 0. tenuilamelluta, Hall, c o IVR, TBH) O. (Remerella) grandis, Lame 178 O. (Schizotreta) ovalis, sp. nov. 179 Orthambonites transversa, Pander, 237 Orihis acutiloba, Ringueberg, 205 oO. acutilirata, Conrad, 5 © . 223 oO. zequivalvis, Hall, : O S . 194, 221 oO. alternata, 203 oO. alsa, Hall, 3 : P 4 . 295 0.? apicalis, Billings, : ‘ ‘ 217, 240 oO. arachnoidea, Phillips, 256 O. arcuaria, Sp. Nov., 224 0. Armanda, Billings, 217 oO. -assimilis, Hall, 224 oO. Aurelia, Billings, 5 : : . 221 oO. basalis, Dalman, . F - 191,192, 207 O. Battis, Billings, 222 0. Baylii, Rouault, 4 243 oO. bellarugosa, Hall, 5 . 222 Orthis bellula, James, Billingsi, Hartt, Billingsi, Safford, biloba, Linne, borealis, Billings, Bouchardi, Davidson, Burlingtonensis, Hall, callactis, Dalman, carinata, Hall, circularis, circulus, Hall, Clarkensis, Swallow, Cleobis, Hall, Clytie, Hall, concinna, Hall, corallina, Waagen, Corinna, Billings, costalis, Hall, crassa, Meek, crenistria, Phillips, crispata, Emmons, Cumberlandia, Hall, cuneata, Owen, cyclas, Hall, cylindrica, Dalyana, Miller, Daytonensis, Foerste, deflecta, Conrad, deformis, Hall, demissa, Derbyi, Waagen, Deshayesi, dichotoma, Hall, discus, Hall, disparilis, Conrad, dubia, Hall, electra, Billings, elegans, Bouchard, elegantula, Dalman, elegantula, var. parva, Ella, Hail, emacerata, Hall, eminens, Hall, Eurekensis, Walcott, Euryone, Billings, Evadne, Billings, excavata, Geinitz, eximia, de Verneuil, expansa, Sowerby, extensa, Pander, fasciata, Hall, fausta, Foerste, fissicosta, Hall, flabellites, Hall,” jlabellulum, Hall, flabellulum, Sowerby, gemmicula, Billings, esossoooessoooososeoooSoSooSoSoSSC SSoOSSSSSs SSSSsSSsgoSsgoS9gasessSo SoS oEe9ess9 biforata, von Schlotheim, Davidsoni, de Verneuil, 365 PAGE. 190, 200, 190, 204, 205, 191, 192, 195, 196, calligramma, Dalman, 190, 191, 192, 193, 194, 195, 231, 238, 242, calligramma, var. Davidsoni, de Vernewil, 193, calligramma, var. flabellites, Foerste, calligramma, var. orthambonites, Billings, 192, 221, 191, 191, 221, 191, 192, 207, 224, 200, 194, 997 227, 221, 217, 224 223 232 219 223 222 217 225 228 219 244 227 228 221 isis SS rm GO OF Ot bo ro bo nO tO rw ty mm 12 oe RE 222 ww w we CS ea 364 Orthis gibbosa, Billings, 220999699999999999999999599959999999999E998588999958999999999999 Halli, Safford, hemipronites, yon Buch, hipparionyx, Schnur, Hippolyte, Billings, Holstoni, Safford, hybrida, Sowerby, idonea, Hall, imperator, Billings, impressa, Hall, incisiva, Waagen, infera, Calvin, insculpta, Hall, insignis, Hall, insularis, Iowensis, Hall, Iphigenia, Billings, Jamesi, Hall, Kankakensis, McChesney, Kaskaskiensts, McChesney, Keokuk, Hall, laticosta, Meek, Laurentina, Billings, lenticularis, Wahlenberg, lentiformis, Hall, Leonensis, Hall, Leucosia,. Hall, lepida, Hall, lepida, Schuur, Livia, Billings, Leonensis, Walcott, loricula, sp. noy., Lucia, Billings, lynx, von Hichwald, Macfarlanii, Meek, Macleodi, Whitjeld, Maria, Billings, marmorea, Waagen, Meeki, Miller, Merope, Billings, Michelini, Leveille, mimica, D 6 2 Minneapolis, NV. H. Winchell, Missouriensis, Swallow, 5 Morganiana, Derby, multisecta, Meek, multistriata, Hall, musculosa, Hail, Mycale, Billings, Nevadensis, Mees, Nisis, Hall, oblata, Hall, occasus, Hall, occidentalis, Hall, Olicierana, de Verneuil, Orbignyi, Davidson, orthambonities, Billings, Oweni, sp. noy., Panderiana, sp. noy., Pecosi, Marcou, pecten, Dalman, pectinella, Emmons, 9 pectinella, Emmons, var. semiovalis, Hall, 2 peduncularis, Hall, INDEX. 194, 195, 221 194, 231, 258 206, 207, 224 194, 219, 225, 343 213, 214, 216, 226 207, 224 : : 212, 226 190, 210, 211, 225, 258 217, 232 210, 224, 225 202, 222 291, 298 . expl. Plate I 210, 225, 226 191 .. 195, 196, 222, 228 22, 298 2226 Orthis Peloris, Hall, 299999999998999999969995999999995999589999995990 es99998999999990 Penelope, Hall, Penniana, Derby, Pennsylyanica, Simpson, Pepina, Hall, perelegans, Hall, perveta, Conrad, planoconyexa, Hall, platys, Billings, plicatella, Hall, porcata, McCoy, prava, Hall, ; 5 productoides, Murchison, propinqua, Hall, punctata, Hall, punctostriata, Quacoensis, Matthew, quadrans, Hall, recta, Conrad, resupinata, Martin, resupinoides, Coz, retrorsa, Salter, retrorsistria, reyersa, robusta, Hall, rugiplicata, Hall, Saffordi, sp. noy., Scovillii, Miller, sectostriata, Semele, Hall, senecta, sp. noy., sinuata, Hall, socialis, solitaria, Hall, spiriferoides, McCoy, . Stonensis, Safford, striatella, Dalman, striatula, Schlotheim, strophomenoides, Hall, subequata, Conrad, subearinata, Hall, 194, 194, 211, . 194, subelliptica, White and Whitfield, suborbicularis, Hall, subquadrata, Hall, superstes, sp. noy., Swallowi, Hall, . Sweeneyi, V. H. Winchell, 194, 196, 196, testudinaria, Dalman, 190, 191, 192, 205, 206, tetragona, Thiemii, White, Tioga, Hall, tricenaria, Conrad, triplicatella, Meek, Tritonia, Billings, tubulostriata, Hall, Tulliensis, Hall, uberis, Billings, umbraculum, Vanuxemi, Hall, Vanuxemi, var. pulchella, Herrick, varica, Conrad, . Wangenheimmi, de Verneuil Wisbyensis, 191, 204, PAGE. 225, 343 211, 225 210, 226 5 295 230, 232 207, 224 207, 224 207, 224 . 218 196, 221 197, 222 255 5 By 212, 226 217 217 232 294 . R22 213, 226 213, 226 197, 222 203 197 262 3 217 218, 340 222 291 225 . 226 198, 212 200 99, 271 ; 994 191, 305 : 213 199, 223 207, 224 207, 22k 925 . 225 197, 341 217, 224 213, 226 222, 298 207, 217 | 218, 224 219 . 225 212, 226 193, 221 194, 221 217, 232 210, 225 212, 226 3 904 248, 256 225, 342 . 295 205, 223 319 207 Orthis Whitfieldi, NW. H. Winchell, -zonata, Dalman, 7 (Dalmanella) arcuaria, sp. nov., (Dalmanell) superstes, sp. noy. (Plesiomys) loricula, sp. nov., (Rhipidomella), Oweni, sp. nov., (Schizophoria) senecta, sp. nov. Oninesina adscendens, Pander, anomala, d’Orbigny, cava, Barrande, crassa, Meek and Hayden, Jestinata, Billings, grandeva, Billings, Missouriensis, Swallow, occidentalis, Newberry, orientalis, Whitfield, transversa, Walcott, Verneuili, Eichwald, Orthostrophia strophomenoides , Hall, Orthothetes desideratus, sp. nov., Orthothetes pecten, Dalman, ooocese essessossseo oO. radiata, Pischer, oO. socialis, Fischer, oO. subplanus, Conrad, oO. umbraculum, von Buch, Patella anomala, Muller, iPS antiquus, Schlotheim, IP. implicata, Sowerby, Paterula Bohemica, Barrande, Pentamerus oblongus, Hall, Pholidops antiqua, Schklotheim, bellula, Walcott, calceola, sp. nov., Cincinnatiensis, Hall, Hamiltonia, Hall, implicata, lepis, sp. nov., linguloides, Hall, oblata, Hall, ovalis, Hall, ovata, Hall, patina, sp. nov., sp. ? squamiformis, Hall, terminalis, Hall, Trentonensis, Hall, Pieceambonttes crassa, Pander, oblonga, Pander, ovata, Pander, planissima, Pander, testudinata, Pander, transyersalis, Wahlenberg, Plicatula striatocostata, Cox, Polytechia apicalis, Whitfield, Producta analoga, Phillips, Foo AP A Pot Dd PO os IB, monilifera, McCoy, Je rugosa, Hisinger, P. truncata, Mall, IP, (Triplecia) monilifera, McCoy, Productella hystricula, Hall, Prc ductus zquicostatus, Hall, 1p, equiradiatus, Shumard, . P. alternatus, Norwood and Pratten, ie, Altonensis, Norwood and Pratien, INDEX. PAGE. 221 191 341 342 341 342 343 191, -237 237 271 262 230 231 266 266 230 . 230 234, 237 - 200 345 350 256 256 b 256 259, 345 122, 150 158 158 79 : 283 157, 159 1357 157, 182 157, 159 157, 159 157, 159 157 157 157 E 157 157, 159 182 . 159 156, 159 5 Aky/ 157, 159 297, 298 300 300 296, 297, 298 . 297 298, 299 265 239 280 270 279 316 271 316 326 326 327 327 Productus Americanus, Swallow, Py POTD AD Ny Po A ey to be I bo A Lae} Ee) Us) Nach Ege) Ee) Tac} Lae) re) ae) aed a Bac) Fa Uae) Igo tae) Ca) Ino} nd ba oe) 3) gs) Ge a Je. Iz, P. arcuatus, Hall, asper, McChesney, biseriatus, Hall, Burlingtonensis, Hall, Chesterensis, Worthen, Christiani, de Koninck, clavus, Norwood and Pratten, comoides, Sowerby, complectens, Etheridge, . compressus, Waagen, Cora, d@’ Orbigny, costatus, Sowerby, dissimilis, Hall, ermineus, de Koninck, Geinitzianus, de Koninck, genuinus, Kutorga, Hallianus, Walcott, horridus, Sowerby, Lasallensis, Worthen, latirostratus, Howse, Leonhardi, 5 Dlangollensis, Day jdeons longispinus, Sowerby, magnus, Meek and Worthen, marginicinctus, Proué, Martini, Sowerby, mesolobus, Phillips, mytiloides, Waagen, Nebrascensis, Owen, Newherryi, Hall, nodosus, Newberry, Nystianus, de Koninck, 9 opuntia, Waagen, ovatus, Hall, pileiformis, Newberry, Prattenianus, Norwood, proboscideus, de Verneuil, punctatus, Martin, Rogersi, Norwood and Prattens scabriculus, Martin, semireticulatus, Martin, splendens, Norwood and Pratten, striatus, Fischer, subaculeatus, Murchison, sulcatus, Castelnau, symmetricus, McChesney, tenuicostatus, Hall, umbonillatus, Davidson, vittatus, Hall, Wortheni, Hall, (Daviesiella) Llangollensis, ine dFeorD, (Etheridgina) complectens, Ztheridge, (Proboscidella) proboscideus, de Verneuitl, Pronites adscendens, Pander, humilis, Pander, oblonga, Pander, (Clitambonites) adscendens, Popblep. Rafinesquina alternata, Conrad, R. expansa, Sowerby, Richthofenia Lawrenciana, de Koninck, Rhinobolus Davidsoni, sp. nov., R. Galtensis, Billings, Rhynchonella angulata, Geinitz, 325, 327, 329 365 PAGE. 326 327 327 327 327 327 327 i 334 317, 318 316, 335 326 326 327 332 334 327 334 332 . 327 327, 332 320 : 326 317, 318 316, 332 327 327 325 327 326 263, 325, 327 329 326 334 327 326 326 326, 333, 33£ 327 327 327 . 332 326, 334 317, 328 250 327 327 320 327 327 317 335 333 234, 235, 237 238 238 238 250, 286 250 . 14 45, 176 45, 176 217 366 Ramerella grandis, Vanuxem, Scenidium areola, Quenstedt, Baylii, Rouault, devonicum, Walcott, Grayix, Davidson, Halli, Safford, insigne, Hall, Lewisi, Davidson, Lewisi, var. Meelleri, Tschernyschew, pyramidale, Hall, Shallockense, Davidson, uralicum, Tschernyschew, chizambon ? Canadensis, Ami, ? fissus, Kutorga, typicalis, Walcott, Schizocrania filosa, Hall, S.? Helderbergia, sp. noy., s. Schucherti, sp. nov., Schizopholis rugosa, Waagen, Schizophoria senecta, sp. noy., Schizotreta conica, Dwight, Ss. elliptica, Kutorga, Siphonotreta aculeata, Kutorga, anglica, Morris, conoides, Kutorga, Jjissa, Kutorga, fornicata, Kutorga, micula, McCoy, Minnesotensis, sp. noy., Scotica, Davidson, DNDN DM nH Hh wD win tentorium, Kutorga, unguiculata, con Hichwald, verrucosa, de Verneuil, Spirifer audaculus, Conrad, crenistria, Phillips, hemiplicatus, Phillips, Lamarcki, Fischer, senilis, Phillips, Waldronensis, Miller and Dy er, Streptis Grayi, Davidson, Streptorhynchus cardinalis, Whitfield, Correanus, Derby, crenistria, Phillips, (ef) pinta ttt s eusarcus, Abich, Hallianus, Derby, incurvus, Abich, ? lepidus, Schnur, orientalis, Pandora, Bilinese pectiniformis, Davidson, pelargonatus, von Schlotheim, 2 primordiale, Whitfield, . pyramidalis, Newberry, tenuis, Hall, Ulrichi, sp. noy., tr ophalosia excavata, Geinitz, Goldfussi, Minster, Keokuk, Beecher, lamellosa, Geinitz, Leplayi, Geinitz, . RAP NDNNDDNNH HI w Cia aa Hughesi, Dutiha, Lewisi, var. Woodlandense, Davidson, Scotica, var. Canadensis, Ami, crenistria, var. senilis, Phillips, 111, 111, 242, 116, 116, 114, 116, 143, 132, 144, 143, 144, 136, 128, 114, 115, 112, 113, 109, 111, 112, 255, 256, 256, 257, 265, 265, 267, 268, 316, 320, INDEX. Strophalosia numularis, Winchell, SS, parva, King, 6 . Ss. plicosa, Waagen, Ss. radicans, Winchell, Ss. Rockfordensis, sp. noy., Ss. scintilla, Beecher, Stropheodonta arcuata, Hall, 8. Becki, Hall, Ss. Blainvillii, Billings, s. Calvyini, Miller, Ss. Canace, Hall and Whitfield, Ss. Cayuta, Hall, 8. demissa, Conrad, Ss. filosa, Davidson, s. inzequistriata, Hall, Irene, Billings, Junia, Hall, Leblanci, magnifica, Hall, magniyentra, Hall, nacrea, Hall, . = perplana, Conrad, profunda, Hall, textilis, Hall, Tallia, Billings, variabilis, Calvin, Riovhodanin striata, Hall, 8. Jasciata, Hall, St Marae alternata, Conrad, antiquata, Sowerby, camerata, Lall, Chemungensis, Conrad, clausa, de Verneuil, Conradi, sp. nov., deflecta, depressa, Dutertrii, Murchisont euglypha, Dalman, expansa, Sowerby, explanata, Sowerby, Jilosa, Sowerby, fluctuosa, Billings, funiculata, grandis, Hallie, Miller, Hecuba, Billings, Hendersoni, Davidson, Holli, Davidson, . Jukesi, Davidson, Kingi, Whitfield, Leblanci, Rouault, Leda, Billings, lepis, Bronn, Minnesotensis, N. H. Winchell, Narajoana, de Verneuil, nitens, Billings, 2 palma, Kayser, patenta, Hall, pecten, Dalman, Philomela, Billings, planoconyexa, Hail, planumbona, Hail, recta, Conrad, rhomboidalis, Wilckens; {PE Oa ea ata tag: 247, 245, 249, 250 316, 320, 335 316, 353 316, 320, 336 286, 2388 287, 239, 292 143, 148, 249 249, 250, 25: i) aw ¥ 249, 288 249, 251 249, 255 Strophomena rugosa, Hisinger, siluriana, Davidson, sinuata, Emmons, squamula, James, Steini, Kayser, subplana, Conrad, subtenta, Conrad, Thalia, Billings, Ulrichi, James, unicostata, Meek and Wor tent Winchelli, sp. nov., Wisconsinensis, Whitfield, Woolworthana, Hall, (Leptzna) planumbona, Halt, TrODhoMmenes Slexilis, Rafinesque, levigata, Rafinesque, trophonella ampla, Hall, cexlata, Hall, cayumbona, Hall, Conradi, Hall, euglypha, Dalman, funiculata, Sowerby, Headleyana, Hall, hybrida, Hall, Leayenworthana, Hall, patenta, Hail, punctulifera, Conrad, radiata, Hall, reversa, Hall, semifasciata, Hall, striata, Hall, leurerselroie hemiplicatum, Hall Terebratula Andii, d’Orbigny, UE, Gaudryi, d’Orbigny, YH, Michelini, d’Orbigny, Terebratulina septentrionalis, Terebratulites biforatus, ms pelargonatus, von Schlatnetn RARNDUARRDHMAMN ROD DD nintnn new oP ta T. (Schizocrania) superincreta, Barrett, Ps 250, 251, 249, 248, 249, 248, 291, 291, 291, 250, 250, 291, 291, 291, 291, 291, 291, 200, INDEX. AGE. 252 283 | 251 283 288 255 251 251 283 282 344 251 255 252 252 | 252 293 293 292 292 292 | 292 292 293 292 292 | 292 | 292 293 292 | 292 | 216 217 217 217 | jos terminalis, Zmmons, 16 202 267 144 Trimerella acuminata, Billings, uns Billingsi, Dall, uns Dalli, Davidson and King, Au, grandis, Billings, T Lindstveemi, Dall, 4b. Ohioensis, Meek, 4b Wisbyensis, Davidson and TB, Triplecia extans, Hmmons, Tl Ortoni, Meek, Triplesia cuspidata, Hall, Bee? Grayie, Davidson, laeleney Maccoyana, Davidson, nucleus, Hall, primordialis, Whitfield, putillus, Hall, radiata, Whitfield, Wenlockensis, Davidson, Trematis Bohemica, Barrande, cancellata, Sowerby, corona, Salter, erassipuncta, Ulrich, Dyeri, Miller, fragilis, Ulrich, Huronensis, Billings, millepunctata, Hall, Montrealensis, Billings, oblata, Ulrich, “Ty Ottawaensis, Billings, ay pannulus, White, AM, punctata, Sowerby, aus punctostriata, Hall, ot uy BREHESHHR ” pustulosa, Hall, quincuncialis, Miller and Den ??7T. rudis, Hall, T. umbonata, Ulrich, Tropidoleptus carinatus, Conrad, Volborthia recurva, Kutorga, 270, 271, 268, 270, 270, 40, 142, 139, 140, 273 271 271 271 270 271 271 272 271 270 142 142 142 142 142 142 142 142 142 142 142 94 141 142 142 142 144 142 139 148 95 Been. ri Nop aa eee t rs Ben REPRODUCTIONS OF DALMAN’S PLATES I AND IL. Accompanying his paper entitled : ‘‘ Uppstalling och Beskrifning af de i Sverige funne Terebratuliter. See Page 192. “ ExpiLicatio FIGURARUM: “Tab. I. Fig. 1, Leprana rugosa His. Fig. 2, a, b, Leprana depressa Sow., c, ejusdem Var.; d, valva intus visa; e, valva altera in- tus visa, cum dentibus cardinalibus ; — f, margo cardinalis; g, sectio ambarum longi- tudinalis, a latere visa, ut representaret valyas compressas et angulum, quem format margo reflexus. ~ Fig. 3, a, Leprana euglypha: 3, b, eadem a latere visa, magn. nat. — 3, ¢, striz in testa ele- vate, cum interstitiis undulatis, magn. auct. Fig. 4, a, b, Leprana transversalis: magn. nat. — 4, c, d, eadem magn. auct. Fig. 5, a, Orruis striatella: valva major; b, figura hujus valve convexitatem representaus. Fig. 6, a, Orruis Pecten: valva major, — b, valva altera; c, valve majoris strie, magn. auct. ; d, valve alterius striae, magn. auct. DALWIAINS PiPPRIRPFATCTA SUERCANA, JW .Dalman del by re “0a Aa ane ae ats te : Bah ised Sanat Fie er pret a0 +e ‘“EXpLicaTio FiGURARUM. “Tab. II, Fig. 1, a, Orruis zonata, valva major, retusa; b, eadem, valva minor; c¢, d, e, eadem species a basi et a lateralibus visa. Fig. 2, Orruis callactis a. Fig. 3, a, b, c. d: Orruis calligramma. Fig. 4, a, b, c, d, Orruis testudinaria ; — 4, e: sulci cum striis, magn. auct. Fig. 5, a, b, c, d, e: Orruis basalis. Fig. 6, a, b, c, d: Orruts elegantula; — 6, e: hujus speciei valva major intus visa; 6, f: valva minor intus visa; g, valva minor a basi visa, ut represententur dentes cardinales. Fig. 7, a, b, c, d: Orruis demissa.” DALMANS DISTRIB EACTA SUIECANA, JW Dalman del ranient er als Reine & ae ¢ erie oe a > Fide aye F ‘ ty : oy We See ETAT PEAS ANDany PEA NATIONS Legend. iin, als Fig. 2 Fig. 3 Fig. 4. Fig. 5 Fig. 6 Fig. 7 Fig. 8. PLATE: 1. Concrete centrals. Transmedian scars. . Cardinal area. . Median septum. . Lateral septa. . Vascular trunks. . Vascular branches. yg. Umbonal scars. 1. Lateral scars. k. Middle laterals. j. Anterior laterals. 1. Outside laterals. x. Concrete laterals. Vv h. Central sears. 3. . Profile of the same. X 3. . A brachial valve; drawn from a gutta-percha impression of a natural mould of the exterior. Natural size. . The interior of a brachial valve; showing the radiate ornamentation of the surface and the faint muscular ridges near the beak. X 2. . A brachial yalve in which the cardinal margin is not transverse, as in the other examples fig- ured, but is strongly reentrant. 2. Georgia group. Swanton, Vermont. Kuroreina Latourensis, Matthew. A pedicle-valvye; drawn from a gutta-percha cast from a natural mould of the exterior. 6. Profile of the same. X 6. . Cardinal view of the same; showing the open triangular fissure. X 6. St. John group. Portland, New Brunswick. MESOTRETA, Kurorea. Page 109. = Mersorrera TENTORTUM, Kutorga. . The pedicle-yalye; copied from KurorGa’s work, Ueber die Brachiopoden-familie der Siphono- tretee, pl. vii, fig. 4c. Lower Silurian. Russia. SIPHONOTRETA, Verneumm. Page 110. é SIPHONOTRETA UNGUICULATA, Verneuil. . Cardinal portion of the pedicle-valve; showing the inner extension of the sipho, which is appar- rently atrophied and czecal. 23. A similar portion of another valve in which the sipho is open. (Kurora@a, op. cit., pl. vi, fig. 3, a, b.) . A portion of the shell near the anterior margin, munch enlarged to show the tubular structure, the epidermal layers and the mode of origin of the hollow spines. (Kuroraa, op cit., pl. vi, fig. 2c.) 26. The interior characters of both valves as given by Davipson. (Geological Magazine, 1877, pl. ii, figs. 9, 11.) SCHIZAMBON, Watcorv. Page 113. ScCHIZAMBON TYPICALIS, Walcott. The interior of a pedicle-valve ; showing an oval foramen with the groove or depressed track, and diverging lateral muscular ridges. X 5. . The exterior of a brachial valve; showing the radiating and concentric strie. In this specimen the surface appears finely granulose, the granulations probably being the bases of minute spinules like those represented by Mr. Watcorr (Palzont. Eureka Dist., pl. i, fig. 3d). . The interior of a brachial valve; showing the outline of the muscular area and its subdivision by diverging ridges. X 5. . Another interior of a brachial valve, differing from the foregoing in the less conspicuous division of the muscular area. The inner pair of diverging ridges terminate anteriorly in deeply col- ored, oval areas, which are too strongly elevated in the figure. X 5. Lower portion of the Pogonip group. Bureka District, Nevada. BRA CEHIOP OWA. Generic Illustrations. Paleont. N.Y.Vol. IV. Pt.ii= Vol. VII. Plate lV. [Ee E.smunous del. Phil -Astlith. ‘ , f = - * ~ ' : 1 ak: i a - we . ze 2 = - a * z el aM os Fig. 31. 35. 36. 37. 38. PLATE IV—Continued. ScHizaMBon (?) rissus, Kutorga. A pedicle-valve; showing the external character of the aperture. After Kuror@a, op. cit., pl. vii, fig. 5a’). > 2.5. SCHIZAMBON (?) FISSUS, var. CANADENSIS, Ami. . A brachial valve from which the shell is partially broken; showing the impression of an internal median septum. All the spines have been removed except those at and near the margins. These have been pressed together in one plane, giving them the appearance of being more closely set than when standing at their normal angle upon the surface. X 2. . The pedicle-valye ; showing the external character of the pedicle-passage. X 2. . A pedicle-valve from which most of the shell has been broken, giving a cross-section of the sipho near its inner extremity. X 2. A brachial valve, the correlate of fig. 34. The surface retains most of the shell, but the spines are broken, showing only their bases, except at the margins where a portion of their length is retained. X 2. A pedicle-valve, so broken as to show the inner edge of the sipho. ee above specimens are from the horizon of the Utica slate. Mear Gloucester, ntario. ; SrPHONOTRETA (?) MINNESOTENSIS, sp. Noy. View from the brachial side of a specimen retaining the valves in juxtaposition and preserving most of the epidermal layer of the shell. The spine-bases about the beak are noticeably large and more closely set than over the rest of the surface, where they occur at considerable dis- tances along the concentric varices. The entire length of the spines is evidently not repre- sented in the fringe about the margin. X 2. The opposite valve of the same specimen. The imperfection of the valve in the umbonal region has rendered it impossible to determine with accuracy the generic character of the species. X 2. Trenton Limestone. Minneapolis, Minnesota. | PLATE IVa. Legend. a. Deltidium. k. Platform-vaults. b. Deltidial slope. m. Median scars. c. Deltidial ridges. q. Crown of the crescent. d. Aveal borders. r. Sides of the crescent. i. Umbonal chambers. t. Transverse scars. j. Platform. TRIMERELLA, Bi.ines. Page 33. TRIMERELLA GRANDIS. Billings. Fig. 1. An internal cast, viewed from the brachial side ; showing the low umbonal chambers, the length Fig. 6 Bigs al 1c] ey ge ro) Fig. 10. of the platform-vaults and the lateral scars of the crescent. . The reverse of the same specimen; showing the much greater prominence of the umbonal cham- bers in this valve. The anterior margin and casts of the yanlts have been slightly restored in the drawings. ; Niagara group. Near Sinking Spring, Ohio. TRIMBRELLA OnroEnsis, Meek. . A small pedicle-valve ; showing a distortion of the umbo which extends to the posterior portion of the platform. The drawing is made from a gutta-percha impression, and the shell is some- what restored in the umbonal region. Niagara group. Port Byron, Illinois. . A brachial valve; showing the inenrvature of the beak, the subumbonal ridge merging into the crescent, the broad lateral scars of the crescent, the long, relatively narrow platform with its medially depressed surface, and the sirong anterior septum. Drawn from a gutta-percha impression of a natural cast. Niagara group. Rising Sun, Ohio. . Cardinal view of an internal cast of both valves, the pedicle-valve being above. The posterior margin of the brachial valve shows the impression of the umbo and beneath it a deep depres- sion representing the crescent; the deltidial slope of the pedicle-yalye is also visible. 3. Brachial view of the same specimen; showing the different lengths of the platform-yaults and the deep umbonal chambers of the opposite valve. Niagara.group. Genoa, Ohio. . View from the brachial side of a specimen retaining the shell; showing also the cardinal area and deltidium of the opposite valve. . The deltidium and cardinal area, drawn from a gutta-percha impression taken from the specimen represented in figure 9. Slightly enlarged. . An internal cast of the pedicle-valve of a large individual. Niagara group. Ottawa county, Ohio. TRIMBRELLA Datur, Davidson and King. An internal cast of a pedicle-valve; showing the umbonal chambers, short platform-vaults ‘and indications of the transverse muscular scars. Guelph limestone. Mew Hope, Ontario. Paleont.N Y VolL{V Ptii=Vol. VIM. BmA CEtOwW oO wD Generic INustrations . PlateIVA. PLATE IVs. Legend. a. Deltidium. k. Platform-vaults. b. Deltidial slope. m. Median sears. ce. Deltidial ridges. n. Anterior scars. ea. Cardinal area. _ 0. Lateral scars. cr. Crescent. q. Crown of crescent, d. Areal borders. r. Side of crescent. h. Cardinal buttress. t. Transeverse scars. i. Umbonal chambers. u. Pallial sinuses. ; j. Platform. x. Umbo-lateral scars. TRIMERELLA, Broures. Page 33. TRIMERELLA Linpstrant, Dall. Fig. 1. The interior of an imperfect pedicle-valve; showing the deep excavation at the base of the del- tidium in the place usually occupied by the cardinal buttress. Aymestry limestone. Island of Gotland. TRIMERELLA GRANDIS, Billings. Fig. 2. An internal cast of a portion of a small pedicle-valve. Fig. 3. The opposite side of the same. Guelph limestone. Galt, Ontario. Figs. 4, 5. Transverse sections, showing the structure of the platform. TRIMERELLA acuMINATA, Billings. Fig. 6. The interior of a pedicle-valve, somewhat restored about the umbo; showing the platform, lateral scars of the crescent and the excavate cardinal buttress. From a gutta-percha impression of a natural cast. Niagara limestone. Port Byron, Illinois. RHINOBOLUS, Hatt. Page 44. RuiNosotus Gavrensis, Billings. Fig. 7. The interior of a pedicle-valve; showing the narrow deltidium, broad deltidial ridges and the small, imperfectly developed platform. The drawing is made from a gutta-percha impression of a mould of the interior, the specimen being that originally taken as the type of the genus. Guelph limestone. Galt, Ontario. Fig. 8. The interior of a small brachial valve. Guelph limestone. Hlora, Ontario. Fig. 9. The interior of a larger brachial valve; drawn from the specimen figured by Wuirsaves on plate 8, fig. 3, Paleozoic Fossils, vol. iii, pt. 1. Guelph limestone. Hespeler or Durham, Ontario. RurNopoLus DAVIDSON, sp. nov. Fig. 10. A small pedicle-valve, showing the internal characters. From a gutta-percha impression of a natural cast. Fig. 11. The interior of a brachial valve, believed to belong to the same species. Fig. 12. The interior of a larger brachial valve; showing the undeveloped platform, the crescent and the transverse muscular scars. Niagara limestone. Grafton, Wisconsin. Fig. Fig. 13. 21. PLATE IV p—Continued. DINOBOLUS, Hatt. Page 36. Dinogpotus Conrapt, Hall. An internal cast of a brachial valve, indicating very distinetly the muscular impressions and the minute platform-yaults. Niagara limestone. Grafton, Wisconsin. . An internal cast of a young pedicle-valve ; showing the close approximation of the platform-vaults. Niagara limestone. Near LeClaire, Iowa. . An internal cast of a pedicle-valve; indicating the duplicate platform-vaults. Niagara limestone. Racine, Wisconsin. . An internal cast of a pedicle-yalve in which the vaults of the platform attained unusual length. . The counterpart of the same; from a gutta-percha impression. Niagara limestone. Near LeClaire, Iowa, . A transverse section of a shell near the anterior edge of the platform, . An internal cast of the pedicle-valye, retaining very distinctly the median and lateral muscular scars and the impression of the crescent. . The counterpart of the same, from a gutta-percha impression; showing the usual size and char- p g p g acter of the deltidium. Niagara limestone. LeClaire, Iowa. The interior of a pedicle-valve, having the deltidium extremely developed. From a gutta-percha impression of a natural cast. Niagara limestone. Near LeClaire, Iowa. . An internal cast of a brachial valve, the umbonal cavity of which has been filled by thickening of the shell. Niagara limestone. LeClaire, Iowa. . An internal cast of a large brachial valve, with the muscular impressions sharply defined. Niagara limestone. Racine, Wisconsin. . An internal cast of a brachial valve; showing the unsymmetrical development of the vaults of platform, two on one side and three on the other. Niagara limestone. JLeClaire, Iowa. BRA CHIOPODA. Generic Ilbastratons Paleont. N.Y.Vol.IV.Ptii= Vol. VIII Plate lV. B. E.Emmons del. Phil Ast.hith. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. PLATE IVc. Legend. a. Deltidium. j. Platform. b. Deltidial slope. k. Platform-vaults. c. Deltidial ridges. m. Median sears. ca. Cardinal area. n. Anterior scars. eg. Cardinal groove. o. Lateral scars. cr. Crescent. q. Crown of crescent. d. Areal borders. r. Side of crescent. h. Cardinal buttress. u. Pallial trunks. 4 i. Umbonal chambers. w. Secondary pallial sinuses. MONOMERELLA, Briiures. Page 40. MonomereLLA Newserryt, Hall and Whitfield. 1. An internal cast of the brachial valve, indicating a strong crescent and low umbonal chambers. bo iS] 10. Til. 13. 14. 15. . The reverse of the same specimen; showing the short umbonal chambers and the deep cardinal groove. Niagara limestone. Genoa, Ohio. MonoMERELLA (crf. ORBICULARIS, Billings). . Profile view of an internal cast. . Another view of the same specimen; showing the internal features of the pedicle-valve. . The cardinal groove and the crescent are very conspicuous, the umbonal chambers short, scarcely reaching the hinge, and the lateral muscular impressions very sharply developed. . The opposite side of the same specimen ; showing the low umbonal chamber, the strong crescent, and incipient platform-vaults. Niagara limestone. Between Grafton and Cedarburg, Wisconsin. MoNnoMERELLA PRISCA, Billings. . An internal cast of a portion of the pedicle-valve, in which the cardinal area is very high and the platform slightly unsymmetrical. . The interior of a pedicle-valve, drawn from a gutta-percha impression of the specimen represented in fig. 6, and slightly restored about the anterior portion. . The interior of a pedicle-valve, in which the deltidium is narrow and elevated, the deltidial ridges obscure, and the areal borders smooth. From a gutta-percha impression of a natural cast. . An internal cast of a pedicle-valve, in which the umbonal chambers have their usual length. The crescent and lateral scars of the platform are unusually distinct. An internal cast of the pedicle-valve, in which the umbonal chambers are of unequal length. An internal cast of both valves, to which a portion of the matrix adheres; showing the thickness of the shell in the umbonal regions. . An internal cast of a brachial valve, with indistinct radiating, probably vascular furrows in the anterior region. An internal cast of a brachial valve ; showing the characteristic markings of the shell. Niagara limestone. Hawthorne, Illinois. MONOMERELLA ORTONT. sp. nov. An internal cast of the pedicle-valve, in which all the characters of the shell are very sharply defined. The counterpart of the same valve, from a gutta-percha impression; showing the broad deltidium without evidence of subdivision, the conspicuous cardinal slope and groove, the crescent and platform scars and the pallial trunks with their ramifications. Niagara limestone. Rising Sun, Ohio. PLATE IV c—Continued. MonoMERELLA EGANT, s). nov. Fig. 16. A brachial valve; showing the strongly developed cardinal area, the narrow crescent and the platform scars. The umbgnal cavity is filled by a thick deposit of testaceous matter. Niagara limestone. Grafton, Wisconsin. MoNOMERELLA OVATA, var. LATA, Whiteaves. Fig. 17. The brachial side of an internal cast, believed to belong to this variety. The umbonal cavity is broad but well defined, the crescent and platform scars strongly developed. The three diverg- ing furrows in front of the platform are probably to be regarded as yascular markings. Fig. 18. The opposite side of the same specimen; showing the very short umbonal chambers. Niagara limestone. Hawthorne, Illinois. BRA GHIOPGAdDWA. Generic Illustrations. Palzont.N Y Vol IV.Ptii=Vol. VII. : PlatelV C. EEmmons del. a. m VITA TI Meibiled. 7 bie if necgits toe iiholl Mami fyi ' 5 ) aya Patt bore tigen Bisel) i tae 7 ' TW nsone) = SeSpesrm aon > = ; nrod IsotA oe tpoesherane suits: , -saet te : atalino denoducktl of ———— ; : arrontglo apwaad ATS we te WOM M2. ¢ pwawk Adag Ata Or (iiy oot wey laso lerotnt an ee Sessa oer hoot by nh Hels laced onke ServeGde pct baee tee iH % his slizoyqo sips ‘ signi yave wonsysi * parideslHt a Pw sis 8 qe -aaytgle a my asd ot bovasfotl dlode ‘oulte goin art 5 tae 9bia vonei oil p gies davai W iy bowbianue s Roos: ail wana aidd to- ROD SvoNny cotdigo ‘acrAeTO Ww BA Hivode vaaontliel ave Rts} Bey) p10 of 2a inane OMAN OVATION OF Yhbe < usa nag ‘Suge Silt fo 10isoles & OUWOTNO LO weRBieonrt dylan, NYdoan) Eta ORO : ibisio xa sult eiehvad) He tO Pye pa mre fener de Ievatuk ine avai ty ay eory sf reby qlqiaite oiceoal ea as ds ee is paiement 1 Jeg Tania ino sie dunce Aly Soe ashes Tl eee Shoteontl siege Brent isis & I 1o6rsixs od'E iS Fl ob Aq i NG alien ae re TANS 1 go ates jet ei ey Ey = “beat paluiooso'cu anti Nigeria eProt.al -losne Bintooe Tehri aaeaeie Y oye PLATE IVb. Legend. a. Deltidium. m. Median scars. * b. Deltidial slope. n. Anterior scars. ec, Cardinal area. o. Lateral scars. eg. Cardinal groove. p- Postmedian scars. cr. Crescent. q. Crown of crescent. d. Areal borders. 1. Side of crescent. i. Umbonal chambers. u. Pallial sinuses or ridges (?). if (Je) 10. 11. 13. 14. 15. j. Platform. MONOMERELLA, Bruuines. Page 40. Monomereiia Krvat, sp. noy. An internal cast of a pedicle-valve; showing the yery short umbonal chambers and the sharply defined muscular impressions. . The opposite side of the same specimen; showing the internal characters of the brachial-valve. Niagara limestone. Hawthorne, [llinois. MONOMERELLA, sp.? . The inner side of a specimen retaining the shell, believed to be a brachial valve of some species of this genus. This specimen is considered by WuireAves as the pedicle-valve of Rhinobolus Galtensis, Billings. Should Mr. Wurreaves’ opinion prove correct, it will probably be neces- sary to remove BiniiNas’ species to some other genus. . The exterior of the same specimen. Guelph limestone. Galt, Ontario. MonoMERELLA GREENII, Sp. Novy. . An internal cast of a pedicle-valve; showing the extremely small umbonal chambers and the sharply defined crescent, cardinal groove and Jateral scars. Niagara limestone. Grafton, Wisconsin. . An interior cast of the brachial valve; showing a portion of the broad area of contact, the plat- form scars, with the diverging anterior ridges. Niagara limestone. Rising Sun, Ohio. . The interior of a brachial valve, from a gutta-percha cast of a natural impr ession. The crescentic fulcrum is exceedingly strong and the platform very obscure. . An internal cast of a pedicle-valve ; showing the very broad cardinal margin and its lateral exten- sion; also the faint umbonal cavities and the conspicuous cardinal groove and crescent. . The interior of a brachial valve, with sharply defined terminal scars and anterior ridges. From a gutta-percha cast. An internal cast of a brachial valve; showing, in the matrix, the impression of the cardinal area. The platform scars are accompanied by scarcely any thickening of the shell. Niagara limestone. Grafton, Wisconsin. MoNOMERELLA OVATA, var. LATA, Whiteaves. The exterior of a pedicle-valve. From the original specimen figured by Wurreaves (Palzozoic Fossils, vol. iii, pt. 1, pl. 2, fig. 2a). . A portion of the interior of a pedicle-valve. From Wnuirravess’ original (op. cit., pl. 8, fig. 2). Guelph limestone. Durham, Ontario. MoNOMERELLA Ovara, Whiteaves. View from the brachial side of a fine specimen retaining the valves in conjunction. Profile of the same. From Wurrnaves’ original specimen (op. cit., pl. 8, figs. 1, 1a). The interior of a pedicle-valve ; showing the broad cardinal area and deltidial slope, the shallow umbonal chambers, the deep car dinal groove and lateral scars of the crescent, and the slightly elevated anterior edge of the platform. From WurrEaves’ original specimen (op. ei. pi. 5 fig. 16). : Guelph limestone. Durham, Ontario. oS t=] BRA CHEIOPOWA. tratons. Ss Thu: LC Gener PlatelV. D Vol. VIII. N.Y.Vol.IV.Pt.ii Paleont. Phil. Ast lith. E.Emmons del. ns Fig. Fig. Fig. Fig. Fig. PLATE IV ez. Legend. F. Foramen. aa. Anterior adductor scars. p. Pedicle-area. pa. Posterior adductor scars. g. External pedicle-groove. : ve. Retractor scars. eg’. The corresponding internal eleya- t. Lateral scars. tion. ar. Anterior muscular ridges. DISCINISCA, Datu. Page 120. bo ol 10. 11. 13. 14. 15. 16. 17. DIsCINISCA LAMELLOSA, Broderip. . The exterior of a pedicle-valve ; showing the broad, depressed pedicle-area, and the oval, direct perforation. . The interior of the same specimen; showing the characters of the pedicle-area, of which an en- larged view is given on Plate IV F. Recent. Peru. . The interior of a brachial valve; showing the muscular impressions. After Davipson. (Trans. Linn. Soc., Ser. 2, Zodl., vol. iv, pl. 26, fig. 4. 1888.) SCHIZOTRETA, Kurorea. i Page 120. ORBICULOIDEA (SCHIZOTRETA) OVALIS, sp. Nov. . A pedicle-valve from which the shell has been partially broken; showing the short foraminal groove. X 3. . Profile view of the same specimen; showing the convexity of the conjoined valves. X 3. Trenton limestone. Middleville, N. Y. Scuizorrera conica, Dwight. . The interior of a brachial valve ; showing its extreme shallowness and also indicating the position of the anterior adductor sears. XX 2. From the original specimen figured by Dwicur (Amer. Journ. Science, vol. xix, pl. xxi, fig. 11. 1880). . An imperfect pedicle-valve; showing the great elevation of the apex and the short foraminal groove. X 2. From the original specimen, op. cit., fig. 3. Trenton limestone. MWewburgh, NV. Y. . Outline profile of the conjoined valves. After Dwicur. ORBICULOIDEA (SCHIZOTRETA ?) TENUILAMELLaTA, Hall. . The exterior of a brachial valve ; showing the elevated somewhat lamellose growth-lines. XX 2. Niagara group. Western New York. The exterior of a pedicle-valve. Profile of the same. (This is the Discina clara of SpeNcER, = D. solitaria, Ringueberg.) Niagara limestone. Hamilton, Ontario. ORBICULOIDEA, D’Orpreny. Page 120. Oumomerman = ASTROS Hall. . The exterior of a brachial valve. x 2. Trenton limestone. Middleville, N. Y. ORBICULOIDEA bDiscus, Hall. The interior of a pedicle-valve ; showing the elevated and much calloused walls of foraminal passage, and the opening at its posterior extremity. Lower Helderberg group. Nea Clarksville, N. Y. ORBICULOIDEA NUMULUS, Sp. nov. The exterior of a pedicle-valve. Lower Helderberg group (Waterlime). Marshall, N. Y. ORBICULOIDEA MEDIA, Hall. A brachial valve. Hamilton group. Seneca county, N. Y. A pedicle-yalve. Chemung group. Trowpsburg, N. Y. The interior of a pedicle-valve, retaining the shell over the posterior segment only, but showing the elevated pedicle-area and the perforation at its distal extremity. Hamilton group. Ontario county, N. Y. Fig. Fig. Fig. Fig. Fig. Figs. 19, 20. PLATE IV E—Continued. ORBICULOIDEA Ranpatit, Hall. . The exterior ofa pedicle-valve; showing, from compression, the apical muscular ridge, the radiating pallial sinuses and the internal track of the pedicle-furrow extending toward the margin and interrupting the concentric growth-lines. The overlapping marginal portion of the opposite valve is seen about the posterior are of the circumference. Natural size. Hamilton group. Net Schoharie, N. Y. OBICULOIDEA PULCHRA, sp. Doy. The exterior of a pedicle-valve. 1.5. Cuyahoga shale. Berea, Ohio. OrBicuLoIppa Mannarrannnsis. Meek and Hayden. The interior of a pedicle-valve ; showing the character of the pedicle-area, the radiating vascular lines, and where the shell is broken on the anterior portion, the character of the external ornamentation and the unusual thickness of the valve. Coal Measures. Riley county, Kansas. CG@HLERTELLA, s.-GEen. Noy. Page 120. CHHLERTELLA PLEURITES, Meek. . The interior of a pedicle-valye; showing the elevated pedicle-ridge and the open, marginal fora- men. Natural size. Profile of the same, giving the internal elevation of the pedicle-area. 23, 24. Brachial valves, differing slightly in outline, and showing the posterior position of the apex. Waverly group. Newark, Ohio. LINDSTRGEMELLA, S.-GEN. NOV. Page 120. LInpsSTR@MELLA ASPIDIUM, Sp. NOV. . A brachial valve, from which the shell is largely exfoliated, but retaining sufficient to show the dis- tinct, elevated, concentric ridges characterizing the external surface. The great lateral ridges and the fainter median septum are represented by furrows. At the posterior extremities of the former are seen two small subcircular muscular impressions, while the scars of the anterior adductors are strongly developed. Natural size. . The counterpart of the same; drawn from a gutta-percha impression, showing all the internal characters in their natural relief. Hamilton group. Near Hamilton, N. Y. . Anatural cast of the exterior of a large pedicle-valve believed to belong to this species ; showing the character of the surface ornamentation, and the peculiar undulation of the concentric ridges on approaching the pedicle-area; The pedicle-passage ditters from that in the normal mature. ORBICULOIDEA, in not being closed, though its margins appear to be in contact. The characters of this area as represented in the drawing, have been slightly restored from other specimens. Hamilton group. Near Leonardsville, N. Y. . Asmall pedicle-valve, with the characteristic ornamentation and strongly developed foraminal groove. Hamilton group. Near Darien, N. Y. RG@MERELLA, s.-GEN. Nov. Page 120. R@MERELLA GRANDIS, Vanuxem. . The exterior of a brachial valve. Hamilton limestone. Falls of the Ohio. . The interior of a pedicle-valve from which the shell has been partially exfoliated, exposing the matrix and the cast of the external pedicle-groove. . The counterpart of the same specimen, froma gutta-percha cast; showing all the essential ex- ternal characters. The extreme depression of the anterior portion of the valve and the cor- respondingly great elevation of the pedicle-area are features subject to some slight variation within the limits of the species. Hamilton group. Cazenovia, N. Y.- BRA CHIORPOWA. trations eneric Illus Cr Plate 1V. E Vol. VIII. Paleont.N.Y.Vol.IV.Pt.ii Phil Asthith. mmons del. Dy | | i \ Ell + ’ i u - ‘ i 7 = . i x " " . t 4 Gal 7 = . a ' _— | , a ' - * [ ‘ , - { + t re 3 > % ; F ’ + sy J z ‘ ' i ig = Ss U . S ‘ - . : z . “S . 5 , A ; PLATE IV vr. Legend. F. Foramen. |. Lateral walls of the groove. p. Pedicle-area. ar. Anterior muscular ridges. p’. Areal callosity. s. Median septum. g. Base of the external pedicle-groove. y. Vascular sinuses. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Figs. Fig. wo bo als 10. g’. Base of the internal pedicle-groove. DISCINISCA, Dat. Page 120. 4 DiscinisicA LAMELLOSA, Broderip. : . The internal pedicle-area, enlarged to three diameters from the specimen represented in Plate IV 5, fig. 2. The pedicle-area is a somewhat thickened elevation, corresponding to the deep depression on the external surface of the valve. The foramen transects the area directly, and between it and the posterior margin 1s a narrow translucent lamina, across which the concentric ornamentation of the valve does not pass. SCHIZOTRETA, Kurorea. Page 120. OBICULOIDEA (SCHIZOTRETA ?) TENUILLAMELLATA, Hall. The exterior pedicle-area of a specimen in which the groove is extremely short. X 5. A similar view of a specimen in which the groove is relatively larger, and the base, walls and foramen well defined. X 5. The corresponding parts in another specimen. XX 5. The groove of the same; showing that the concentric growth-lines are retained on the broad lat- eral walls, while the base is smooth though less distinctly detined than insome instances. X 16. . The pedicle-characters of the interior, drawn from a natural cast of the exterior, in which, from the compression of the shell, the internal characters are preserved in continuity with those of the outside. Niagara limestone. Hamilton, Ontario. ScnizorreTa conica, Dwight. . The external characters of the pedicle-area ; from the specimen represented in Plate IV g, fig. 7. x3 ORBICULOIDEA, D’Orpsreny. Page 120. ORBICULOIDEA PULCHRA, sp. noy. . The internal pedicle-area. The elevated median ridge corresponding to the base of the external groove, is slightly broken, a crack extending to the foramen. About tke anterior moiety of the ridge the lateral callosities have just begun to form. X 3. . The same, in a more advanced stage of development. ‘The callosities have increased to such a degree as to have almost come into contact for the entire length of the area, leaving the posi- tion of the internal ridge mdicated by the groove between their edges. X 3. Cuyahoga shales. Berea, Ohio. The same parts, still showing a remnant of the groove formed by the meeting of the lateral cal- losities ; also indicating the position of the foraminal opening. X 3 Cuyahoga shales. Baconsberg, Ohio. 11, 12. The same features, from individuals in which the lateral callosities have coalesced, leaving the 13. 30. iv) bo foramen open, but otherwise concealing the structure of the area. X 3. The interior of the apical portion of the brachial valve ; showing the small median septum, extend- ing forward from the apex. X 3. Cuyahoga shales. Berea, Ohio. An internal cast of a brachial valve; showing the impressions of two strong, diverging vascular sinuses (?) and finer markings about the margin. X 1.5. Cuyahoga shales. Newark, Ohio. A very young pedicle-valye, with a length of 2.25 mm., having the posterior margins of the aperture unclosed, while the pedicle-groove has nearly its entire normal length. X 12. Cuyahoga shales. Berea, Ohio. ORBICULOIDEA, compare O. PULCHRA. 14, 15, 16. The internal characters of the pedicle-area ; showing the envelopment of the ridge by the 17. lateral callosities, in various stages of adyancement. X 3. Waverly group. Meadville, Pa. ORBICULOIDEA MARGINALIS, Whitficld. The internal characters of the pedicle-area. The callosities have assumed an irregular, but bi- laterally symmetrical form, almost enveloping the pedicle-ridgé. x 3 Hamilton group. Cementville, Wis. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 18. 19: 20. 31. PLATE IV r—Continued. OrpicuLompEA NEwperryl, Hall. The same features; showing the strong elevation of the area, but the absence of callosities, the large foramen, the sharply defined, though flattened median ridge and lateral walls of the pedicle-passage. X 3. Waverly group. Cuyuhoga Falls, Ohio. (From the original locality, a ferruginous band about 110 feet below the conglomerate.) (HHLERTELLA s.-GEn Nov. Page 120. CEHLERTELLA PLEURITES, Meck. The internal characters of the pedicle-area; showing the open marginal foramen, the elevated, radially striated latera) walls, the median ridge and a short apical septum. X 3. The same features from a iother specimen, in which the walls of the area are smooth and the apical septum absent. X 3. Waverly group. Newark, Ohio. ORBICULOIDEA, D’Orpteny. Page 120. ORBICULOIDEA LOpENSIS, Vanuxem. . The internal characters of the pedicle-area; indicating the unusual breadth and depth of the base of the groove and the low lateral walls ; also the interruption in the ornamention of the shell from the foramen outwards, probably indicating the line of union of the primitive margins of the aperture. X 4. Genesee shale. Lodi, N. Y. ORBICULOIDEA, sp. indet. . A natural cast of the interior apical portion of the brachial valve ; showing the anterior and pos- terior muscular ridges. XX 3 Chemung group. Warren, Pa. OrBICULOIDEA NitTrpa, Phillips. . The pedicle-area of an extremely young shell, having a diameter of 1mm. The foramen is a y g gs marginal slit extending, with divergent edges, for almost the entire radius of the valve. At the apex, the pedicle-greove appears in an incipient stage. X 50. . A considerably later stage of development of these parts, the diameter of the shell being 5 mm. ;. showing the margins of the foramen united for most of their length, but still separated at the posterior edge of the valve. The structure of the area is somewhat obscured by the compres- sion of the specimen. X 12. . A later stage of growth, exhibited by a specimen 7 mm. in diameter. Here the angles made by the edges of the foramen with the posterior edge of the shell are acute and approximate. The pedicle-grooyve has progressed so as nearly to fill the eutire hiatus. X 7 Figures 23-25 are from a block of black shale upon which valves of this species are crowded in great numbers, to the exclusion of other fossils. The condition of the pedicle-area in its later development, as shown in the following figures, is also amply represented in these specimens. Lower Coal Measures. Springfield, Illinois. The internal pedicle-area of a small but mature individual; showing the base and lateral walls of the groove and the slight callosity at the apical extremity. XX 7. . The external surface of a similar specimen ; showing the general form of the groove at maturity, and the absence of any furrow or interruption of the concentric ornamentation beyond its pos- terior extremity. X 7. . The entire valve, of which fig. 27 represents the pedicle-area. X 2. Coal Measures. Gover, Missouri. . The interior of a pedicle-valve ; showing the base of the groove, the foramen and the muscular impressions. (After Davipson. Brit. Carb. Brach., Suppl., pl. xxx, fig. 13 a.) OrRBICULOIDEA, sp.. Meek. «An impression of the outside of the under valve in the matrix (slightly less than natural size), with portions of the thin shell adhering, so as to show the smooth inside, and a prominent internal ridge, corresponding to a deep external furrow, with a small, round or oval foramen at its outer end.” (Menk, Paletology of Eastern Nebraska, plate iv, fig. 3, and Explanation.) Coal Measures. Wear Nebraska City, Neb. BRA CHILOPOWA. stratons. ic Iku Gener Plate lV F Vol. VIII. Paleont.N.Y.Vol.IV.Pt.ii Phil. Astlith. E.Emmons del, cc i 7 a * + i! Rau vie’ = a a J re a : i) uw - : iv r 0 ae t iY err 5 ’ : - i i 4) : a > ey 5 € ioe iy, (i ts : ae , by 1" y ¢ I ¢ tts ns . * : Fig. 1 Fig. 2 Fig. 3 Fig. 4 ime, — 5 Fig. 6 loti, 7 Iie, Fig. 9 Fig. 10. Fig. 11. Fig. 12. Fig. 13. Fig. 14. Fig. 15. Fig. 16. Fig. 17. Fig. 18. Fig. 19. PLATE IVa. Legend. 5B. Brachial valve. c. Central scars. P. Pedicie-valve. pe. Posterior centrals. F. Foramen. ce. Median centrals. p. Pedicle-callosity (in brachial valve). ac. Anterior centrals. g. Pedicle-groove. pa. Posterior adductors. g’. Base of groove. pa’. Anterior element of posterior ad- 1, Walls of groove. ductors. s. Median septum. aa. Anterior adductors. o. Posterior muscular scars. TREMATIS, Suarer. Page 138. TREMATIS TERMINALIS, Emmons. . The interior of a brachial valve; showing the posterior and central muscular scars and the lingui- form median elevation. XX 3. . An internal cast of the pedicle-valve ; showing the great depression of the pedicle-area, the median ridge corresponding to the pedicle-groove, and the vascular sinuses. X 3. Trenton limestone. Middleville, N. Y. TREMATIS, sp., compare T. puNcTosrRiaTa, Hall. . The internal pedicle-area ; showing the elevation of the margins of the fissure. X 4. Hudson River group. Frankfort, Ky. TREMATIS MILLIPUNCTATA, Hall. . The interior of a brachial valve ; showing the posterior callosity. forming a surface for the passage of the pedicle, the external muscular scars and the components of the central impressions. X 2. Hudson River group. Covington, Ky. . An internal cast of a brachial valve, to which a portion of the shell adheres. X 2. . The exterior of a brachial valve, from which the shell is partially exfoliated. 2. . Profile of an internal cast of the conjoined valves. . Anterior view of the same specimen, exposing the pedicle-valve and the projecting apical portion of the brachial valve. X 2. Hudson River group. Cincinnati, Ohio. . The interior of a brachial valve ; showing the posterior muscular scars beneath the broken pedi- cle-callosity. XX 1.5. Hudson River group. Frankfort, Ky. The external ornamentation. X 25. TREMATIS PUNCTOSTRIATA, Hall. The exterior of a brachial valve. X 2. The interior of a pedicle-valve. X 2. The external ornamentation. X 25. Trenton limestone. Clifton, Tenn. TREMATIS FRAGILIS, Ulrich. A pedicle-valve ; showing the short and narrow pedicle-fissure. Hudson River group. Bank Lick Creek, Ky. TREMATIS OrrTaweENsis, Billings. External view of a brachial valve. From a gutta-percha cast of the exterior. Natural size. The surface ornamentation. X 25. Trenton horizon. Frankfort, Ky. The external pedicle-area, from a specimen referred with doubt to this species. X 3. Hudson River group. Cincinnati, Ohio. TrREMATIS UMBONATA, Ulrich. The exterior of the brachial valve. X 2. The same specimen, with the upper portion of the brachial valve removed, exposing the flat lower valve and its pedicle-fissure. XX 2. From the original specimen figured by Utricw (American Geologist, vol iii, No. 6, p. 378, fig. 8. 1889). Hudson River group. Covington, Ky. Vig. Fig. Fig. Fig. Fig. Fig. 34. PLATE IV G—Continued. TREMATIS OBLATA, Ulrich. . The brachial valve, retaining a portion of the external ornamentation. % 2. From a gutta-percha cast of the original specimen (op. cit., fig. 19). Hudson River group. Cincinnati, Ohio. SCHIZOCRANIA, Hani and Wuairriep. Page 142. SCHIZOCRANIA (?) RupIsS, Hall. . The exterior of the brachial valve. 2. Trenton limestone. Clifton, Tenn. ScuizocraNta FILosa, Hall. . The exterior of a brachial valve, attached to Strophomena alternata. X 2. Hudson River group. Cincinnati, Ohio. . The exterior of a large brachial valve. 24. The pedicle-valve. Utica slate. Mohawk Valley, N. Y. . A valve of Strophomena alternata, to which five of these shells are attached, all of them exposing the lower valve. The figure is taken from the Palzontology of Ohio, vol. ii, pl. i, fig. 12, and the musenlar scars on the internal cast of the upper valve, shown in the left of the illustration, remain as there rep- resented, . An internal cast of the brachial valve ; showing the elongate, converging posterior scars, separated into posterior and anterior elements; also a faint median ridge extending forward beyond the muscular impressions. X 3. . The pedicle-valve seen on the right margin of fig. 25; showing the apical pedicle-callosity or incipient groove. X 2. Paleontology of Ohio, vol. ii, pl. i, fig. 15. . The pedicle-area viewed from within; showing more accurately the character of the apical cal- losity, its median ridge and lateral walls indicating homology with the corresponding parts in the genus ORBICULOIDEA =X 3. Hudson River group. Cincinnati, Ohio. . An individual from which the upper portion of the brachial valve has been removed, exposing all the internal characters of the pedicle-valve. X 2. It will be observed that in this figure, as well as in figs. 25, 33, 34 and 35, the diameter of the lower valve is less than that of the upper, and the former lies aboye and within the base of the latter, the attachment of the shell being largely effected by the marginal portions of the larger valve. Hudson River group. Covington, Ky. . An internal cast of a brachial valve; showing the anterior and posterior muscular scars. The former impressions are rarely discernible. X 1.5. Trenton limestone. Trenton Falls, N. Y. SCHIZOCRANIA SCHUCHERTI, Sp. Noy. . A brachial valve, retaining a portion of the external ornamentation, but showing the posterior muscular sears. xX 3 . A smaller brachial valve, retaining most of the exterior surface. XX 3. . An individual from which most of the upper valve has been removed, exposing the pedicle-valve. The features of the pedicle-area are not so clearly retained as to allow delineation. X 3. Hudson River group. Covington, Ky. < SCHIZOCRANIA (?) HELDERBERGIA, sp. Nov. The exterior surface of an individual; showing the pedicle-valve, its coarsely radiate and obscure concentric striation, and the overlapping edges of the finely striated upper-yalve. The character of the pedicle-aperture is not well retained. X 2. 5. The internal surface of the pedicle-valve ; showing what appears to be a broad pedicle-fissure, and the overlapping margins of the upper valve. xX 3. Lower Helderberg group. Near Clarksville, N. Y. VEG; Plate 1 Ilhastrations. Generic BRACHIOPODA. Vol. VII N.Y.Vol.IV.Ptii nt. Palao ee ae S oe 0.0:9.0.0.0.0, 6.006.064 fee a 6.6.0,0.0.0.0.0.0.0.0 6 peer seeerest. | eres OL OG O6.6.0.6.0.6 6 Phil.Astlith. E.Emmons del. Fig. Fig. Fig. Fig. Fig. Fig. Fig. PACE UTR atte Legend. pa. Posterior adductor scars. m. Median muscular fulcrum. aa. Anterior adductor scars. vy. Vascular sinuses. bo lor) 13. 14. 15. 16. Wie . La b. Brachial muscular sears. CRANIA, Rerztus. Page 145. Cranra Lara, Hall. . Four individuals attached to the pedicle-valve of Streptorhyuchus planwmbonum. Hudson River group. Ozford, Ohio. CRANIA AGARICINA, Sp. Nov. . An individual attached to a branch of TReMATOPORA; showing the characteristic sparse and relatively coarse radiating ribs. X 3. ‘Lower Helderberg group. Near Clarksville. Dia YG CRANIA PULCHELLA, Sp. Nov. . An individual attached to the valve of Orthis subcarinata. It differs from the preceding species in its finer, more numerous ribs and greater size. X 2. Lower Helderberg group. Near Clarksville, NN. Y. Cranta Borpent, Hall and Whittield. . An individual attached to a valve of Spirifer Oweni; showing the very fine radiating strie, and the conformation of the upper valve to the surface of attachment. . Profile of the same specimen. Hamilton limestone. Clarke cownty, Indiana CRANIA CRENISTRIATA, Hall. . The interior of an upper valye; showing the strong anterior adductor scars and very faint poste- rior adductors. X 2. Hamilton limestone. falls of the Ohio. . A portion of a cast of the internal surface in a decomposed chert ; showing the filling of vertical canals. X 25. Corniferous limestone. Canandaigua, NN. Y. . The interior of an upper valve; showing the very strong anterior adductor scars with mar- gins elevated, and the more obscure posterior scars. X 3 Hamilton limestone. Fails of the Ohio. . The exterior of a large upper valve. Natural size. Hamilton group. Canandaigua Lake, N. Y. . A smaller uncompressed individual. . Profile of the same. Hamilton group. Western New York. . A valve of the same, or a closely allied species, attached to Orthis impressa. X 5. Upper Devonian. Rockford, Iowa. Cranta Rowxnyt, Gurley. An individual showing the upper valve. X 2. Choteau limestone. Pike county, Missouri. CRANIA SETIGERA, Hall. An individual, referred to this species with some hesitation ; attached to a branch of Monrrcoxi- pora. It will be observed that for some distance about the anterior edges of the shell, where the valves opened for the admission of food-bearing water-currents, the outward growth of the bryozoan cells has been obstructed. XX 2. Trenton horizon Minneapolis, Minnesota. An upper valve. X 2. Profile of the same. x 2. Trenton limestone. Mineral Point, Wisconsin. CRANIA SPINIGERA, Hall. The original specimen ; an individual attached to the shell of Rhkynchonella Stricklandi. The ornamentation consists of radiating rows of sharply defined tubercles. x 3. Niagara group Waldron, Indiana. Vig. Fig. Fig. 18. 19. 20. 30. 31. 33. 34. 35. PLATE LV h—Continuec, CRANIA SETIFERA, Hall. A somewhat imperfect upper valve. = Niagara group. Waldron, Indiana. CRANIA GRANOSA, sp. Noy. A somewhat distorted upper valve ; showing the finely granulose surface, A portion of the surface enlarged. % 20. Hamilton group. Centerfield, N. Y. CraniA TRENTONENSIS. Hall. 22. Front and profile views of an upper valve. Trenton limestone. Middleville, N. Y. CRrANIA scaprosa, Hall. . A brachial valve of Strophomena alternata, covered with shells of this species all of which carry the radiating and fine concentric ornamentation of the host. . The interior of an upper valve, the external surface of which is overgrown by a Monticutipora. The posterior adductors are larger than the anterior pair, and near their outer edges the small sears of the adjustors are discernible. In this species as usually preseryed the muscular im- pressions appear as dark discolorations of the shell, indicating a probable greater density of the shell-substance. > 2. . The interior of a lower valve. The posterior scars are more distant and smaller than in the opposite valve, while the anterior scars are much larger. > 2. §. A shell of Platystrophia lynx, having the surface of the brachial yalye crowded with individuals of this species. Hudson River group. Cincinnati, Ohio. Cranta MuLtrpuNcrara, Miller (= Crania scabiosa, Wall). . One of a group of individuals attached to a fragment of Monvicuripora. ‘The punctate surface character of the host is impressed upon the shell, giving it a remote resemblance to the surface of Trematis terminalis. X 2. Hudson River group. Covington, Ky. . Another specimen with similar surface markings. X 2. Hudson River group. Blanchester, Ohio. Crania socranis, Ulrich (= Crania scabiosa, Hall). . A fragment of a crinoid colunin, covered with individuals which retain very distinctly the impres- sions of the sutures between the segments. x 3. Hudson River group. Covington, Ky. CRANIA PERCARINATA, Ulrich (= Crania scabiosa, Hall). An individual which has been attached to some species of PLEUROTOMARIA. X 3. Another specimen, which also bears the surface markings of some gastropod. XX 3. Hudson River group. Covington, Ky. These figures are from Mr. Unricn’s typical specimens. CRANIA, sp. nov. ? . The interior of an upper valve of a probably smooth species. X 2.. Lower Helderberg group. Near Clarksville, N. Y. CRANIA FAVINCOLA, sp. nov. A lower valve, slightly broken about the posterior margin, but showing the very large posterior muscular impressions, the deeply impressed anteriors, with sharply elevated margins and median fulcrum; also, the radiating pallial sinuses. The shell is attached to a specimen of Favosites pirum, Davis. Hamilton group. Crab Orchard, Ky. Cranta Leont, Hall. The interior of an upper valve; showing, in addition to the posterior and anterior adductor scars, the faint impressions of the brachial muscles The exterior of an upper valve. Chemung group. Leon, WN. Y-. BRA CEILOPOaDA. Generic Illustrations, Paleont.N.Y.Vol.IV. Ptii= Vol.VI. Plate 1V. H. E.Emmons del. Phil-Astlith. Fig. Jel bpewd MD) 1AVere, Legend. pa. Posterior adductors. p. Parietal impression. aa. Anterior adductors. m. Median impressions. da. Dorsal adjustors. b. Brachial muscular impression. va. Ventral adjustors. v. Vascular trunks. mm. Mesenteric muscular impression. v’. Vascular branches. bo “1 (le) 17. CRANIELEA, Gurert. Page 153. CRANIELLA ULRICHI, sp. nov. . A cast of the interior of a lower valve, somewhat restored on the right side; showing the strong anteri:r and very obscure posterior adductor impressions, and the marks of the vascular sin- uses. The shell is convex and shows no evidence of attachment, though the external surface is overgrown with a bryozoan. Drawn from a gutta-percha cast of a natural interior. 1.5. Trenton limestone. Minneapolis, Minnesota. . The internal cast of an upper valve, believed to be of the same species. The sigmoid vascular impressions are simpler than elsewhere observed; the scars of the dorsal adjustors and of muscles accessory to the anterior adductors (possibly the brachial muscles) are also apparent. Drawn from a gutta-percha cast of a natural interior. > 1.5. Trenton limestone. Minneapolis, Minnesota. CRANIELLA Hamitront®, Hall. . The interior of a lower valve attached to a Srreprerasma; showing the usual character of the muscular scars, viz., anterior and posterior adductors, the ventral adjustors, and post-median or mesenteric impression ; also the characteristic radiating vascular sinuses. : Hamilton group. Canandaigua Lake, N. Y. . The interior of an upper valve. Corniferous limestone. Falls of the Ohio. . The interior of an attached valve. From Paleontology of New York, vol. iv, pl. iii, fig. 23. . Three individuals of different sizes, attached to the surface of Tropidoleptus carinatus. Opero citato, pl. iii, fig. 19. Hamilton group. Western New York. = . The interior of a lower valve; showing the usual muscular and vascular impressions, and very great thickening of the shell. x 2. . An upper vaive; showing the modification of the surface from attachment to an individual of Spirifer audaculus. . Profile view of a normal shell, attached to Tropidoleptus carinatus. Hamilton group. Canandaigua Lake, N. Y. . The exterior of an upper valve. From Thirteenth Rept. State Cab. Nat. Hist., p. 76, fig. 3. 1860. e Hamilton group. Western New York. - An upper valve, modified by attachment to the post-lateral portion of aright valve of Cypricardella (Microdon) bellistriata. Hamilton group. Canandaigua Lake, N. Y. . An individual greatly modified by attachment to Tropidoleptus carinatus. . An internal cast of a large upper valve; .showing the usual muscular scars and the peculiar sigmoid vascular trunks with their ramifications. Hamilton group. Pratt's Falls, N. Y. An internal cast of a very convex upper valve, greatly modified by attachmeut. X 2. Hamilton group. Canandaigua Lake, N. Y. . An internal cast of an upper valve; showing the characteristic impressions. xX 2. Hamilton group. Bellona, N. Y. - An internal cast of a convex and apparently free lower valve ; showing the closer approximation of the anterior and posterior adductor scars than in the opposite valve, the deep impresssion of the mesenteric muscle, and the radiating vascular sinuses. he figure is slightly restored on the left side. xX 2. Hamilton group. Centerfield, N. Y. PHOLIDOPS, Hatt. Page 155. Puotipors Trenronensis, Hull. A slightly crushed specimen. X 4. Trenton limestone. Middleville, NV. Y. PHOLipors CINCINNATENSIS, Hall. . The exterior of a normal specimen. xX 4 Hudson River group. Cincinnati, Ohio. Fig. Fig, Fig. Fig. Fig. 20. 24. PLATE IY 1—Continued. PHOLIDOPS SUBTRUNGCATA, Fall. . The exterior of an individual; showing the slightly flattened posterior slope and faint median angulation. X 4. Hudson River group. Lorraine, N. Y. Prontpors ovauis, Hall. The external surface ; showing the characteristic outline and subcentral apex. 6. Niagara group. Waldron, Indiana. PHOLIDOPS SQUAMIFORMIs. Hall. . The interior of a large ventral (1) valve ; showing the character of the muscular area, the median, anterior adductor, lobed posterior adductor, and parietal impressions. X 5. Niagara group. Hamilton, Ontario. PuHowipors ovata, Hall. . Anintermal cast of a dorsal (?) valve; showing the sharply defined anterior and posterior ad- ductors, and the parietal scar. X 6. . The interior of the opposite valve ; showing the relatively small size of the muscular area. 6. Lower Helderberg group. Wear Clarksville, N. Y. PHOLIDOPS ARENARIA, Hall. An internal cast of a dorsal (?) valve. From the original specimen. X 2. Oriskany sandstone. Knox, IV. Y. PuHouipors AREOLATA. Hall. . An internal cast of the ventral (!) valve. X 3. Schoharie grit. Wear Clarksville, N. Y. An internal cast of the opposite valve. X 3. Schoharie grit. Knox, NN. Y. PHOLIDOPS PATINA, Sp. Nov. . The exterior of a valye ; showing the lamellose growth-lines, crossed by fine, interrupted, radiat- ing strie. Drawn froma gutta-percha cast of a natural mould in decomposed chert. x 4. i 28. ‘The interior of a dorsal (?) v alve. From a gutta-percha cast. XX 4. 30. 37. . The exterior of the shell. x 4. . Profile of the same specimen showing the valves in conjunction. X 4. 29. The interior of the opposite valve. X 4. Corniferous limestone. De Cewville, Ontario. PHOLIDOPS CALCEOLA, Sp. Novy. The interior of a dorsal (?) valve ; showing the terminal beak and subapical area, and the character of the muscular impressions. X 12. Corniferous limestone. Falls af the Ohio. Puotmors Hamitrontm, Hall. Hamilton group. Western New York. . The interior of a ventral (?) valve; showing the character of the muscular impressions. XX 8. . The interior of the opposite valve ; showing the muscular and parietal sears. X 4. Hamilton group. Canandaigua Lake, N. Y. PHOLIDOPS LINGULOIDES, Hall . The interior of a dorsal (?) valve; showing the terminal and slightly deflected beak, the subapical area, and the character of the muscular scars. X 2. Hamilton group. Highteen Mile Creek, NN. Y. PHoLipors opuata, Hall. . An internal cast of the dorsal (2) valve, with two deep anterior adductor scars, the posterior ad- ductors being very faintly developed, as in the preceding figure. This and figure 35 may represent the same species. X 4. Hamilton group. Carter's Mills, N. Y. PHouipors, compare P. HamiLronr™. The exterior of the shell; showing the form and outline. X 6. Bedford shales. Bedford, Ohio. BRA CHIOPODA. Generic Illustrations. Paleont. N. Y.Vol.IV.Pt.ii= Vol. VII. Plate lV. I E.Emmons del. Phil.Ast.lith, PLATE. IV x. PATERULA, Barranpbe. Page 78. PATERULA (?), Sp. Fig. 1. The interior of a pedicle-valve, taken from a natural cast of the intermal surface. The broad marginal border, narrow fissure and radiate muscular markings, indicate the close agreement of this fossil with PargruLa. X 5. Quebec group. South St. John’s Market, Quebec. MONOBOLINA, Satrer. Page 83. Monopouina PLUMBEA, Salter. Lo Fig. . Exterior of a brachial (?) valve. X 3. Fig. 3. Interior of a similar valve. X 3. (Davipson, Brit. Sil. Brach., pl. 1, figs. 23, 24.) ORBICULOIDEA, D’Orpteny. Page 120. ORBICULOIDEA, sp. ? Fig. 4. The interior of a brachial valve; showing a faint median apical septum and radiating muscular ridges. X 2. é St. Louis limestone. Crittenden county, Ky. LINGULA, Brucuiire. Page 2. LINGULA LINGUATA, sp. nov. Fig. or . The pedicle-yalve from which the epidermal layer is partially exfoliated ; showing the peculiar deflection of the anterior margin, which is a constant feature. X 2. Clinton group. Near Hamilton, Ontario. LINGULA, sp. (?). Fig. 6. An internal cast to which a fragment of the shell adheres. The surface is covered with minute papille, which are probably casts of the inner openings of the vertical canals. X 5. Black slate (Genesee horizon). Near Vanceburg, Ky. LincuLta WaveERLIENSIS, Herrick. Fig. 7. View from the pedicle-valve, of a specimen retaining the impression of the pedicle. Waverly sandstone. Oil City, Penna. LINGULA THNIOLA, sp. nov. (=Lingula lamellata, Hall, Pal. N. Y., vol. ii, p. 55, pl. xx, figs. 4a, b,c. 1847). Fig. 8. The pedicle-valve ; showing the peculiar surface ornamentation, crossed near the beak by con- centric growth-lines. X 1.5. Clinton group. Clinton, NV. Y. LincuLa cuNEATA, Conrad. Fig. 9. An internal cast of a pedicle-valve ; showing the muscular scars and vascular sinuses. X 3. Medina sandstone. Medina, N. Y. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig 10. 14. e i) Py bo bo to bw ~ PLATE LV k—Continued. LINGULA LAMELLATA, Hall. View from the pedicle-valve of an internal cast, retaining the impression of the lateral and central muscular sears and of the pallial sinuses. ‘The matrix is filled with minute ovoid bodies (ova), which appear to be distributed wherever the sinuses and their branches have extended. About the anterior and lateral margins of the valve the matrix is the opaque mud of the sediment; elsewhere the spaces between the ova are translucent. X 3. . The opposite side of the same specimen; also showing the muscular, vascular and septal impres- sions. The intermixture of the opaque matrix on this side is somewhat greater than on the other, obliterating the ova to some extent. X 3. . A thin section of a portion of this specimen, which shows the ovoid bodies to be opaque and homogenous. X 12 . An enlargement of the surface of the cast ; showing the appearance of the ova when magnified 12 diameters. ‘The vertical ridges are casts of radiating furrows on the interior of the valve. Niagara group. Near Hamilton, Ontario. LINGULOPS, Hatt. Page 18. Lineutops GRANTI, sp. noy. The interior of a brachial yalye. XX 6. ‘The iriterior of a pedicle-valve. The muscular areais here developed into a well-defined plat- form, while in the other species of the genus, L. Whitfieldi and L. Norwoodi, it still retains its linguloid character. X 6. Niagara group. Hamilton, Ontario. CONOTRETA, Watcort. Page 104. Conorrera Rusti, Walcott. 3. Anterior view of a pedicle-valve. The apical and anterior regions retain a portion of the shell, but elsewhere the shell is removed, showing the impressions of the internal radiating museular ridges. X 4. . An internal cast of a smaller pedicle-valve ; showing the impression of the strong apical callosity, and the radiating ridges. X 8. : . An apical view of the same valve ; showing the subtriangular posterior slope, and its obscurely defined median furrow. X 9. . Cardinal view of a very young individual, in which the posterior slope is very faint. X 12. Trenton limestone. Zventon Falls, N. Y. . Cardinal view of another very smal] example, retaining the shell. - Profile of same. X 25 Hudson River group. Covington, Ky. OBOLUS, Etcuwatp. Page 80. Oxo.us [?] PULCHER, Matthew. . The exterior of a valve, retaining the shell and showing the character of its ornamentation. X 3. St. John group. Caton’s Island, New Brunswick. DISCINA, Lamarck. Page 120. Discina srrriata, Schumacher. . The interior of a pedicle-valve. . The exterior of a similar valve. Much enlarged. Recent. Cape Palmas. (After Davipson. Trans. Linnean Soc., Ser. 2, Zool., yol. iv, pl. 25, figs. 24, 25. 1889.) BRA CHLIOPRPOWA. Generic I[huistratons. Paleont.N.Y.Vol.IV.Pt.ii=Vol.VIIL. Plate IV K J E.Emmons del. Phil. Ast. hth. PLATE V. (Figures 1-8, 13, 18-26, 29-36 by E. EMMONS; 9-12, 14-17, 27, 28, 87-41 by RK. P. WHITFIELD.) Legend. A. Deltidium. a’. Posterior adductor impressions. t. Teeth. r. Anterior diductor impressions. j. Cardinal process. 1’. Posterior diductor impressions. fp. Crural plate. v. Vascular markings. a. Anterior adductor impressions. s’. Deltidial plate or callosity. ORTHIS Datman. 1828. Page 136. OrvTHISs, as restricted. Page 192. ‘‘ORTHIS ORTHAMBONITES (Pander) ” Billings.* Figs. 1, 2. Exterior and interior views of a pedicle-valve. X 3. Fig. 3. Interior of a brachial valve. From Mr. Brutines’ original specimens. ‘‘ Point Lévis; in the upper part of Limestone No. 2, Quebec group.” Orruis Euryone, Billings. Fig. 4. Exterior of a pedicle-valve; from the original specimen. ‘* Point Lévis; in the upper part of Limestone No. 2, Quebec group.” Ortruis Davipsont, de Verneuil. Fig. 5. Interior of a pedicle-valve; showing the character of the cardinal and muscular areas. Fig. 6. Profile of an individual haying the valves in conjunction. Fig. 7. A portion of the exterior of the pedicle-valve; showing the fine transverse striz and the openings of sparsely scattered, oblique tubules, which penetrate the outer layers of the shell. X 4. Fig. 8. A portion of the cardinal area of the brachial valve; showing the linear cardinal process, crural plates, thickened deltidial area and the low median ridge. X 3. Upper Silurian limestone. Island of Gotland. For further illustration, see Davipson, Silurian Brachio, oda, plate xxxv, figs. 18, 19. ORTHIS TRICENARIA, Conrad. Figs. 9-11. Views of the brachial and pedicle-valyes and the protile of a specimen with valves conjoined ; showing the general exterior characters of this type of structure. Fig. 12. The interior of a pedicle-valve; showing a slight apical accretion or callosity in the delthyrium, and the muscular area in which the impression of the central adductors is unusually developed. Trenton horizon. Mineral Point. Wisconsin. Fig. 13. The cardinal area of a pedicle-valve ; showing the character of the apical callosity partially filling the delthyrium. XX 3. Trenton horizon. St. Paul, Minnesota. Fig. 14. The interior of a brachial valve ; showing the character of the process, crural plates and muscu- ; lar area. For further illustration, see Palzeontology of New York, Volume I, plate xxxii, fig. 6. Orruis cosTauis, Hall. Fig. 15. An internal cast of the pedicle-valye; showing the characters of the muscular area and vascular markings. X 2. Figs. 16, 17. Outline profile and full view of another pedicle-valve. Chazy limestone. Chazy, NV. Y. 7 For further illustration, see Paleontology of New York, Volume I, plate iv bis, fig. 4. PLECTORTHIS, nom. nov. Page 194. ORTHIS PLICATELLA, Hall. Fig. 18. A view of the brachial yalve of a normal adult, a strongly biconvex shell with a moderately low cardinal area and strong, distant, simple ribs. * See note on this species on page 221. The American shell differs from the Russian O. calligramma, var. orthambonites, de Verneuil, in its smaller size, fewer and coarser ribs with tine radial striations, and being thus a quite distinct form, it may receive the designation Orthis Panderiana, nom. noy. Fig. 19. Fig. 20 Fig. 21 Fig.) 22 Fig. 23 Figs. 24, Fig. 26 Figs. 27, Fig. 29. Figs. 30, Fig. 32. Fig. 33. Fig. 34. Fig. 35 Fig. 36. Figs. 37, Fig. 40. Fig. 41. PLATE V—Continued. The deltidial portion of the pedicle-yalve; showing the broad delthyrium and the outline of the muscular area which is not sufficiently thickened to obscure the plications of the shell. X 3. . The area in the opposite valve; showing the cardinal process, crural plates and low median ridge. K 3 Hudson River group. Covington, Kentucky. For further illustration, see Paleontology of Ohio, Volume I, plate viii, fig. 7. Orruis picnoroma, Hall. O. dichotoma, Wall, = O. fissicosta. Meck, not Hall. . The interior of the brachial valve ; showing the cardinal process, crural plates and the character of the plications. Hudson River group. Covington, Kentucky. For further illustration, see Palzontology of Ohio, Volume I, plate viii, fig. 6, under the name of O. fissicosta. Orruis Exvva, Hall. . An indiyidual viewed trom the brachial valye, showing area and foramen of the opposite valve. X 2. . A portion of the interior of the pedicle-valve; showing the characters of the cardinal area. X 3. Hudson River group. Covington, Kentucky. For further illustration, see Paleontology of Ohio, Volume I, plate viii, fig. 9. Orrnis Kanxanensts, McChesney. 25. Brachial and protile views of a normal individual. Hudson River group. Tilmington, Lllinois. Ortmis Waitrietpr, N. YW. Winchell. 3. The interior of a pedicle-valve ; showing the relatively bigh area and strong teeth, the character of the muscular area, and the low ridges radiating from its anterior margin. Hudson River group. Spring Valley, Minnesota. DINORTHIS, nom. nov. Page. 195. ! Orruis PECTINELLA (Hmmons), Conrad. 28. A view of the peilicle-valve, and profile of a specimen in which the ribs are more subdivided toward the margin than is usual in the species. X 2. Trenton limestone. Lewis county, New York. The interior of a small pedicle-valve; showing the subquadrate HRS On eT area with the posterior and anterior diductor and the adductor sears. Trenton horizon. St. Paul, Minnesota. 31. A view from the pedicle-valve and the profile of a large individual, showing the strongly ele- vated, simple ribs. The interidr of a pedicle-valve. The cardinal portion of a brachial valve. X 2. Trenton horizon. Curdsville, Kentucky. For further illustration, see Palzeontology of New York, Volume I, plate xxxii, fig. 1°. Ortuis Swreengyi, N. H. Winchell. Exterior of the pedicle-valve ; showing the depressed-conyex shell. . A profile of conjoined valves; in this figure the pedicle-valve as represented is too convex and too high at the head. The interi ior of the brachial waive: Trenton horizon St. Paul, Minnesota. ORTHIS as restricted. Page 192. ORTHIS FLABELLITES, Hall. 38, 39. The exterior of the pedicle and brachial valves and profile of an average specimen. The interior of the pedicle-valve ; showing the character of the muscular area. The interior of the brachial valve; showing the cardinal process, crural plates and quadripartite muscular area. Niagara group. Lockport, N. Y. For further illustration see Paleontology of New York, Volume II, plate lii, figs. 6, 7. BRACHIOPRPrT ADA. Orthide. Paleont. N.Y.Vol.IV.Ptii= Vol. Vl. Generic [histrations E.Emmons del. Phil Astlith. PLATE V 4. (Figures 2, 4, 16-21, 24-40 by E. Exons; 1, 3, 5-14 by R. P. WHITFIELD; 15 by F. B. Mbrek; 22 by Puinip Asr; 23 by J. C. MCCONNELL.) Legend. A. Deltidium. a’. Posterior adductor impressions. j. Cardinal process. r. Diductor muscular impressions. fp. Crural plate. p. Pedicle-muscular impression. t. Teeth. o. Ovarian impressions. b. Sockets. vy. Vascular markings. a. Anterior adductor impressions. HEBERTELLA, nom. nov. Page 198. Orruis stinuara, Hall. Fig. 1. The interior of a pedicle-valve; giving the character of the muscular area, ovarian and vascular markings. Fig. 2. An enlargement of the muscular area of the pedicle-valve ; showing the large diductor (7), lineal central adductor (a) and the pedicle-scar (p). X 2. Fig. 3. The interior of a brachial valve. Fig. 4. The muscular and deltidial area of the brachial valve; showing the narrow, slightly thickened cardinal process (j), the large crural plates and the quadripartite impression of the adductor muscles. xX 2. Fig. 5. The exterior of a brachial valve. Figs. 6.7. Cardinal and profile views of the same specimen. Fig. 8. Exterior of the pedicle-valve; the area and delthyrium of the opposite valve showing. Hudson River group. Cincinnati, Ohio. For further illustration see Paleontology of Ohio, Volume I, plate ix, fig. 4. Orruis smnuata, Hall. (?) (Compare O. Varia, Billings.) Fig. 9. A view of the brachial valve and profile of a specimen doubtfully referred to this species. Hudson River group... ———— , Ohio. Fig. 1019, by error. ORTHIS OCCIDENTALIS, Hall. (?) Figs. 11, 12. Views of a small specimen with coarse, simple plications, and the median sinus incipiently developed ; probably the young of this species. Hudson River group. Savannah, Illinois. OrtHIs INScULPrA, Hall. Fig. 13. The interior of a pedicle-valve ; showing the muscular, vascular and ovarian markings. X 2. Hudson River group. Ozford, Ohio. : For further illustration see Palzeontology of Ohio, Volume I, plate ix, fig. 1. PLASSIOMYS, Nom. Nov. Page 196. ORTHIS RETRORSA, Salter (= O. Carley, Hall). Fig. 14. The interior of a pecicle-valve; showing the short dental lamellae, subquadrate muscular area, the vascular and ovarian makings. Fig. 15. A view of the pedicle-valve of the orignal specimen; showing the high area and retrorse beak of this valve. Fig. 16. Profile of a large individual; showing the great convexity of the brachial yalve and the degree of resupination of the beak of the pedicle-valve. Hudson River group. Ozford, Ohio. For further illustration, see Paleontology of Ohio, Volume I, plate xi, fig. 7. OrtHIS SUBQUADRATA, Hall. Fig. 17. The interior of the pedicle-valve ; showing the component scars of the subquadrate muscular area, the lateral ovarian areas and the vascular impressions over the pallial region. Figs. 18, 19. Brachial and cardinal views of a normal individual. Hudson River group. Ozford, Ohio. For further illustration, see Paleontology of Ohio, Volume I, plate ix, fig. 2. Figs. Fig. Fig. Figs. Fig. Fig. Fig. Fig. 5 Fig. Fig. Fig. Fig. Figs. 20, PLATE V s—Continued. Orruis porcara, McCoy. 21. Brachial and profile views of an average example; showing the rotundity of the brachial yalye and the resupination of the opposite beak. Middle Silurian. Junction Cliff, Anticosti. For further illustration, see Davipson, Silurian Brachiopoda, plate xxxii, figs. 12-20, ORTHOSTROPHIA, Hatt. Page 199. Ortuis Haru. Safford (?== 0. strophomenoides, Hall). . A view of the pedicle-valve. . A cardinal view of the conjoined valves of the same specimen. Lower Helderberg group. Perry county, Tennessee. ORTHIS STROPHOMENOIDES, Hall. See Plate VI, figs. 32-34. 24. The exterior of a brachial valve. 28, 30. 31. 32. 33. 34. 35. 36. 37. 38, 25. A cardinal view of the same specimen; showing greater convexity than the preceeding species. (The relative position of the valves as represented in the figures 23 and 25 is reversed.) §. The interior of a brachial valve; showing the character of the cardinal process, muscular area, ovarian and vascular markings. . The interior of the opposite valve. The muscular area is greatly thickened and is divisible into the adductor and diductor elements; the vascular sinuses are also very distinct. Lower Helderberg group Near Clarksville, NN. Y. For further illustration, see Paleontology of New York, Volume III, plate xxiii, fig. 7. PLAISIOMYS, nom. nov. Page 196, OrrHis DEFLECTA, Conrad. 29. The exterior of the brachial and pedicle-valves. A cardinal view of the same specimen; showing the elevation of the area, the convex deltidium, and the convexity of the brachial valve. Trenton horizon. Dixon, Illinois. For further illustration, see Paleontology of New York, Volume I, plate xxxiB, fig. 5. Orruis LORICULA, Sp. loy. The cardinal area of the pedicle-valve ; showing the deltidium. The exterior of the pedicle-valve. The interior of the brachial valve. The delthyrium is filled by a callosity which also supports the crural plates and the linear cardinal process ; the deltidium is also present in an incipient condition. The interior of the pedicle-valve ; showing the character of the muscular area, ovarian markings, etc. Galena limestone. Fountain, Minnesota. Ortuis Housront, Safford. Profile of the type specimen. : Cardinal view of the same; showing the wide delthyrium and elevated area of the pedicle-valve. A view of the brachial valve of the same specimen.. Trenton horizon. Near Knoxville, Tennesee. OrTHIS SAFFORDI, sp. nov. 39, 40. Three views of the exterior of a specimen ; showing its general form and the character of its surface markings. Trenton horizon. Near Knoxville, Tennessee. BRA CHIOPRPODA. Cie bin i Gl es. Paleont. N.Y.Vol.IV.Ptii=Vol.VII. Generic Illustrations Plate Vv A E.Emmons del. Phil.Astlith. - j ‘ ' i \ i ’ i wy " + Ss 5 ‘ j ? ‘ — * : \ : \ i i { ; font ; ; if nay mY Al : M ; fe ; PLATE Ves. ” (Figures 3, 4, 8, 15-21, 27-39, by R. P. WHITFIELD; 9, 22-26, by E. Eaarons; 10-14, by J. C. MCCONNELL.) Legend. A. Deltidium. a. Anterior adductor impressions. 8 : s is TERRES I j. Cardinal process. a’. Posterior adductor impressions. t. Teeth. r. Anterior diductor impressions. b. Sockets. 1’. Posterior diductor impressions. ; : I c. Crura. o. Ovarian markings. s. Septum. vy. Vascular markings. p. Pedicle muscle. PLATYSTROPHIA, Kine. Page 200. Ortuis BrroRATA, Schlotheim, var. LYNX, von Hichwald. Fig. 1. A cardinal view of an average individual; showing the area and delthyrium of each valve. (The lines limiting the delthyrium are too strongly defined.) Fig. 2. An exterior of the brachial valve of a smaller specimen. Fig. 3. The interior of a brachial valve; showing the narrow, linear cardinal process, large crural plates and the quadripartite impression af the adductor muscles. Fig. 4. The interior of a large pedicle-valve. The apical portion of the shell has been absorbed, being the usual condition in old shells of this form, thus exposing the impression of the pedicle-muscle. The specimen also shows the compact form of the muscular scars, the vascular trunks and ova- rian markings. Hudson River group. Cincinnati, Ohio. OrTHIS BIEORATA, Schlotheim, var. LATIcosTA, Meek. Figs. 5, 6, 7. Profile, brachial and front views; showing the high median fold characterizing this form. Fig. 8. The interior of a brachial valve. i Fig. 9. Anenlargement of the delthyrial portion of the brachial valve. The obsolescent character of the cardinal process is probably due, in part, to reabsorption. Hudson River group. Cincinnati, Ohio. OrTHIS BIFORATA, Schlotheim. Fig. 10. The exterior of the pedicle-valve. The snrface is covered with fine granules which, however, are very rarely retained (and almost never visible in ordinary specimens). X 3. Trenton limestone. Zvrenton Falls, IN. Y. For further illustration of Pharysrropuia, see Davinson, Silurian Brachiopoda, pl. xxxviii, figs. 11- 25; Paleontology of Ohio, Volume I, plate x. BILOBITES, Linna. Page 204. ORTHIS BILOBA, Linné. Figs. 11, 12, 13, 14. Views; showing the variation in form in this species. Fig. 14 ig of the type described by RinGuEBERG as O. acutiloba. X 3. Niagara group. Lockport, N. Y. OrrHis varica, Conrad. Figs. 15, 16,17. Three views of the same specimen. X 2. Fig. 18. The interior of the pedicle-valve ; showing the area, delthyrium, teeth and outline of the muscu- lar area. X 4. : Fig. 19. The interior of the brachial valve ; showing the cardinal process, the great crura, large muscular area, and the pectinated surfaces of marginal contact. X 5. Lower Helderberg group. Near Clarksville. N. Y. Fig. Fig. Fig. Fig. Fig. Big. Fig. Figs. Fig. Fig. bob rs to bo ou PLATE V p—Continued, HETERORTHIS, nom. nov. Page 202. Orruis Crytie, Hall. . A view of the brachial valve of the type-specimen ; showing the area and foramen of the pedicle- valve. . The interior of a pedicle-valve ; showing the elongate scars of the cardinal muscles and the small adductor impressions. . The interior of the brachial valve. The cardinal process is simple, but very high, and the crural plates are much elevated, terminating abruptly. Muscular area small and obseurely quadri- partite. . The articrlar area of the same valve; showing the divisions of the muscular area. > 2. . The surface ornamentation, consisting of a fasciculate grouping of the radiating striz, crossed by minute concentric lines. X 4. Trenton horizon. Near Prankfort, Ky. DALMANELLA, nom. nov. Page 205, Orruis Evapne, Billings. . A view of the brachial valve of the type-specimen; showing area and foramen of opposite valve. . The opposite side of the.same specimen. “ Point Lévis ; in the upper part of Limestone No. 2, Quebec group.” Orrnis TEStuDINARTA, Dalman. 27, 28, 29. Three views of a small form which may prove to be a permanent variety of the species. 30. . The interior of the brachial valve. X 2. 38. 39. The interior of the pedicle-valve of the same form. Trenton horizon. Mineral Point, Wisconsin. The exterior of the pedicle-valve of a normal individual. . The exterior of the brachial valve of a somewhat larger specimen. . A profile of the same. . The interior of a pedicle-valve ; showing the character of the muscular area. . The interior of a brachial valve, retaining the articulating apophyses and the subdivision of the muscular area. . The central cardinal portion of a similar valve, enlarged to show with greater distinctness the structure of the articulating aparatus. Hudson River group. Oincinnati, Ohio. The interior of a large pedicle-valve. Trenton limestone. Middleville, N. Y. The interior of a brachial valve. X 2. Trenton limestone. Zowville, NV. Y. BRA GEL OPOADWA. Orthide. Palesont.N.Y.Vol.IV. Pt.ii=Vol.VIIL. - Cenerie Lbustratons. Plate VB r i RP Whitfield del Phil.Ast.ith. PLA TRavec: (Figures 1, 2, 6-18, 25-41, by R. P. WHITRIELD; 4, 5, 19, 42-47, by IE. EMMONS; 3, 20-24, by J. C. MCCONNELL.) Legend. A. Deltidium. a. Anterior adductor scars. t. Teeth. a’. Posterior adductor scars. b. Sockets. yr. Diductor scars. fp. Crural plates. o. Ovarian markings. j. Cardinal process. v. Vascular markings. ce. Crura. Fig. Fig. Fig. Fig. Figs. Fig. Figs. Fig. Figs. DALMANELLA, nom. noy. Page 205. ORTHIS EMACERATA, Hall. . The central cardinal portion of the interior of a brachial valve; showing the processes and muscular imprints. X 3. The exterior of a brachial valye. Hudson River group. Cincinnati, Ohio. For further illustration, see Paleontology of Ohio, Volume I, plate viii, figs. 1, 2. ws i) Ortuis Mert, Miller. The interior of a brachial valve; showing the cardinal process, crura and muscular sears. The apparent impressions in the umbo-lateral regions are due to abnormal thickening of the test. ae go Hudson River group. Spring Valley, Minnesota. Ortuts Sronensis, Safford. Profile of a specimen with valves conjoined. X 2. A view of the pedicle-valve of the same specimen ; showing the alternating, fasciculate character of the radiating strie. X 2. Se OrTHIS SUBAQUATA, Conrad. 6. A view of the brachial valve of the original specimen ; showing the area and foramen of the op- posite valve. 7, 8. Profile and cardinal views of the same. 9. The articular and muscular area of the brachial valve. X 3. 10, 11. Interiors of the pedicle and brachial valves. Trenton horizon. Mineral Point, Wisconsin. For further illustration, see Paleontology of New York, Volume I, plate xxxii, fig. 2. OrTHIS PERVETA, Conrad. 12. View from the brachial valve of the original specimen. 13, 14. Brachial and profile views of a larger individual. Trenton horizon. Mineral Point, Wisconsin. For further illustration, see Paleontology of New York, Volume I, plate xxxii, fig. 5. ORTHIS BLEGANTULA, Dalman. . 15, 16. Opposite sides of the same individual; showing the form of the species as occurring at this locality. 17. The interior of a pedicle-valve, somewhat enlarged. 18. The interior of a brachial valve ; showing the muscular impressions and articular processes. X 2. Niagara group. Waldron, Indiana. 19. Cardinal view of the central portion of the brachial valve ; showing the composition of the cardi- nal process, the great elevation of the crural plates and crura, and their furrowed or crenulated outer walls. X 3. Upper Silurian limestone. Island of Gotland. For further illustration, see DAvipson, Silurian Brachiopoda, pl. xxvii, figs. 1-9; Hat, ‘Twenty- eighth Rept. N. Y. State Mus. Nat. Hist., pl. xxi, figs. 11-17. Figs. Fig. Fig. Fig. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Figs. Figs. Fig. Figs. Fig. Fig. Fig. Fig. 20, 22. 23. 24. 25, 29. . The interior of a pedicle-valve. . A natural cast of the interior of the brachial valve ; showing the limits of the muscular area, the 34. 35. 36, PLATE Vc—Continued. ORTHIS ARCUARIA, sp. Noy. (See Supplement for description.) 21. Two views of a silicified, partially exfoliated shell; showing somewhat the contour of O. ¢le- gantula, but haying a more strongly biconvex form. Niagara group. Perry county, Tennessee. Orrnuis WispyEnsis, Lindstrjém. Profile of the pedicle-yalve. The interior of the same valve. The interior of the brachial yalye; showing the cardinal process, crural plates and muscular sears. X 2. Upper Silurian limestone. Island of Gotland. ORTHIS SUBCARINATA, Hall. 26, 27, 28. Views of the exterior of a normal individual; showing its form and contour. The interior of a brachial valve. ovarian spaces and the main vascular trunks. . A similar internal cast of the opposite valve, preserving the ramifications of the vascular sinuses, and showing also the ovarian spaces and muscular scars. . Posterior view of the cardinal area of the brachial valve ; showing the subdivision of the cardinal process and the elevation of the crural plates. Lower Helderberg group. Wear Clarksville, N. Y. For further illustration, see Palzeontology of New York, Volume III, plate xii, figs. 7-21. ORTHIS PERELEGANS, Hall. The interior of a brachial valve ; showing the divergent ridges extending from the line of separa- tion between the anterior and posterior elements of the adductor muscle. Posterior view of the cardinal area of a brachial valve. Lower Helderberg group. Near Clarksville, NN. Y. For further illustration, see Paleontology of New York, violnne III, plate xiii, sre 4-12. ORTHIS LENTICULARIS, Vanuxem (= O. /enfiform7s, Hall). (See note on page 224.) 87. Two views of a small individual. Corniferous limestone. LeRoy, N. Y. 38, 39, 40. Views of a larger, more biconyex specimen. 41. 42, 44. 45. 46. 47. The interior of a pedicle-valve ; showing the character of the muscular area. Corniferous limestone. Caledonia, NN. Y. Ortuis Lronensis, Hall. 43. Interiors of the brachial and pedicle-valyes taken from impressions of natural moulds. Chemung group. Cattaraugus county, NN. Y. For further illustration, see Paleontology of New York, Vclume IV, plate viii, figs. 3-8. ORTHIS SUPERSTES, sp. Noy. (See Supplement for description.) Profile ; showing the couvexity of the shell. A view of the same specimen from the brachial valve. An internal cast of the pedicle-valve; showing traces of the vascular sinuses. The interior of the opposite valve ; retaining similar radiating furrows about the muscular area. Chemung group. Howard, NN. Y. BRA CHIOPOAODA. Orthide. Paleont.N.Y.Vol.IV. Pt ii= Vol. VII Generic Thhistrations Plate WEG, R PWhitfield Phil Astlith. ; . x Z i - - ‘ 5 2 t t : : i , Soi 4 : ‘ . , i Fj 1 \ . . 5 t = Se Z ‘ - ‘ PLATE VI. (Figures 1-34, by R. P. WHITFIELD.) Legend. A. Cardinal area. p. Pedicle-area. t. Teeth. a. Anterior adductor scars. b’. Sockets. a’. Posterior adductor scars, d. Dental Jamellee. r. Anterior diductor scars. ec. Crura. 1’. Posterior diductor scars. s. Median septum. . v. Vascular markings. j. Cardinal process. o. Ovarian markings. . Figs. Fig. Fig. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 1 4. 5. RHIPIDOMELLA, CixHLErt. Page 208. ORTHIS HYBRIDA, Sowerby. , 2, 3. Three views of an average individual of the American form referred to this species. The interior of the brachial valve. The character of the diductor muscular scars is here incor- rectly represented, the impression being quadripartite and not flabellate. The interior of the pedicle-yalve ; showing the expanded muscular scars. Niagara group. Lockport, N. Y. For further illustration, see Davipson, Silurian Brachiopoda, plate xxvii, figs. 1-9; Hatt, Paleon- tology of New York, Volume II, plate lii, tig. 3; Twenty-eighth Rept. N. Y. State Mus. Nat. Hist., pl. xxi, figs. 18-25. OrruHis PENELOPE. Hall. (See Plate VI, fig. 10.) 6, 7, 8. Three views, giving the external characters of a normal mature individual. 14. 15. 16. ito 18. . The interior of a brachial valve ; showing the articulating apparatus. The muscular area is quad- ripartite rather than flabellate. . The interior of a small pedicle-valve. . Similar view of an older shell. . The interior of a pedicle-valve, which shows the thickening about the muscular impressions, ac- companying senility. . An enlargement of the surface striz ; showing the openings of the oblique tubules upon the strize and the scattered puncte. Hamilton group. Western New York. For further illustration, see Palaeontology of New York, Volume IV, plate vi, fig. 2. Orruts VANUXEMI, Hall. (See Plate VI 4, figs. 7, 8.) An enlargement of the surface striz. An internal cast of the pedicle-valve ; showing the pedicle-scar and other muscular impressions. Hamilton group. Cumberland, Maryland. For further illustration, see Palzeontology of New York, Volume LY, plate vi, fig. 3. Orruis Leucosta, Hall. (See Plate VIA, fig. 9.) The interior of the pedicle-vyalve. Hamilton group. Western New York. For further illustration, see Palzeontology of New York, Volume IV, plate vii, fig. 4. SCHIZOPHORIA, Kine. Page 211. Ortuis Troe, Hall. The exterior of a brachial valve. An internal cast of a pedicle-valve. Chemung group. Near Elmira, N. Y. For further illustration, see Paleontology of New York, Volume IV, plate viii, figs. 20-29. PLATE VI—Continued. RHIPIDOMELLA, Giurerr. Page 208, OrtHis OWENI. sp. noy. (See Supplement for description.) Fig. 19. The exterior of a brachial valve. Figs. 20, 21. Interiors of pedicle and brachial valyes, respectively. “‘ Knobstone group” of OwEN, = age of the Waverly. Button-mould Knobs, Kentucky. SCHIZOPHORIA, Kine. Page 211. Orvruis CARINATA, Hall. Fig. 22. An internal cast of a pedicle-valye ; showing the character of the muscular area, at the anterior margin of which are seen traces of the vascular sinuses. Chemung group. Vear Painted Post, N. Y. For further illustration, see Palaeontology of New York, Volume IV, plate viii, figs. 30-32. Orrnis Swauiovi, Hall. Figs. 23, 24. he exterior and interior of the pedicle-valve. Burlington limestone. Burlington, Iowa. Orvruis TuLirensis, Hall. Figs. 2) 25, 26, 27. Three views of a normal individual; showing the great convexity of the brachial valye and the shallow pedicle-valve. Fig. 28. An internal cast of the brachial valve; showing the quadruple muscular impression and the prin- cipal vascular trunks. At y is the filling of the rostral cavity of the opposite valve. Fig. 29. An internal cast of the pedicle-valve. Tully limestone. Keuka Lake, N. Y. For further illustration, see Paleontology of New York, Volume IV, plate vii, fig. 5. OrrHIs PROPINQUA, Hall. Fig. 30. An internal cast of the brachial valve. ‘The subdivision and the course of the vascular sinuses are very sharply retained. Corniferous limestone. Avon, WV. Y. For further illustration, see Palaontology of New York, Volume IV, plate vy, fig. 3. OrvHIs impressa, Hall. (See Plate VI, figs. 2 Fig. 31. s. 26, 27.) 5 ’ An internal cast of the pedicle-valve; showing the subdivisions of the muscular area, and the un- usual arrangement of the vascular sinuses. Chemung group. For further illustration of this species, see Paleontology of N.Y., Volume IV, pl. viii, figs. 11-19. ORTHOSTROPHIA, Hat. Page 199. ORTHIS sTROPHOMENOIDES, Hall. (See Plate Va, figs. 24-97.) Fig. 32. The exterior of an imperfect brachial valve. Fig. 33. An internal cast of the pedicle-valve ; showing the very small muscular area, the ovarian mark- ings in the umbo-lateral regions, and the vascular sinuses over the pallial region. Fig. 34. An internal cast of the brachiai valve, retaining the impression of the simple cardinal process, and showing the four sharply defined adductor scars, the ovarian markings and the ramified vascu- lar sinuses. Lower Helderberg group. Near Clarksville, N. Y. r= BRA CHOP OWA. oS Orthids Generic Illustrations . Paleont. NY-Vol JV, Ptii. aUEEA ahs: 4 3 \ S S ie R.P Whitfield, del. PLATE VIa. (Figures 7-9, 11, 18-25, 29, 32, by E. Emmons; 1, 2, 13-17, 26, 27, by G. B. Smmpson; 3, 4, 6, by R. P. WHITFIELD; 10, 30, 31, by J. C. MCCONNELL; 5, 28, by J. M. CLARKE; 12, copy.) Legend. t. Teeth. a. Anterior adductor scars. j. Cardinal process. a’, Posterior adductor scars. b. Sockets. x. Accessory adductor (brachial valve) fp. Crural plates. vr. Diductor sear. c. Crura. 0. Ovarian markings. de. Deltidial covering (brachial valve). y. Vascular markings. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 1, ite) 10. lil 13. p. Pedicle-muscle. RHIPIDOMELLA, Ctnxert. Page 208. OrtuHis crrcuLus, Hall. 2. Opposite sides of the original specimen of this species. Clinton group. Reynale’s Basin, N. Y. Orruis oBLiatTa, Hall. . The interior of a small brachial valve. . The interior of a pedicle-valve of the usual dimensions ; showing the muscular area. Lower Helderberg group. Near Clarksville, N. Y. For further illustration of this species, see Paleontology of New York, Volume III, plate 10. OrtHis MuscuLosa, Hall. . The interior of a pedicle-valve ; showing the extravagant development of the diductor scars, the narrow adductors and the large impression of the pedicle muscle. Oriskany sandstone. Cuimberland, Maryland. For further illustration, see Paleontology of New York, Volume III, plate xci, tigs. 1-3. OrvrHis PELORIS, Hall. . An internal cast of the pedicle-valve. The area covered by the muscular impressions is unusually restricted though normal for the species. Schoharie grit. Near Clarksville, N. Y. For further illustration, see Paleontology of New York, Volume IV, plate iv, figs. 1, 8-10. Ortuts Vanuxemti, Hall. (See Plate VI, figs. 14, 15.) . The interior of a brachial valve, retaining with unusual distinctness the four scars of the adductor muscles. The ridges radiating from the anterior margin of the muscular area, are probably of vascular origin. Hamilton group. Canandaigua Lake, N. Y. . An internal east of the pedicle-valve. From Drift of the Hamilton group. Near Elmira, N. Y. For further illustration, see Paleontology of New York, Volume IV, plate vi, fig. 3. Orruis Leucosta, Hall. (See Plate VI, fig. 16.) . Aninternal east of the pedicle-valve, with strong muscular sears, and showing the pitting of the ovarian spaces (indicating a premature senile condition 2). From Drift of the Hamilton group. Near Elmira, N. Y. Orruis PENELOPE, Hall. (See Plate VI, figs. 6-13.) An enlargement of the cardinal area of the brachial valve, giving the structure in detail. X 3. Hamilton group. Canandaigua Lake, N. Y. OrTHIS, sp. ? (compare O. Penelope). A pedicle-valve, from which the shell has partially exfoliated ; showing the muscular impressions on the matrix. Waverly group. Granville, Ohio. Orvuis Micueuint, L’Eveillé. . View of the brachial valve of a specimen retaining the spines on a portion of its surface. Copied from Davipson’s Monograph of the Carboniferous Brachiopoda, pl. xxx, fig. 7. Carboniferous shales. Gateside, Ayrshire, Scotland. For further illustration, see Davipson, Carboniferous Brachiopoda, plate xxx, figs. 6-12. Orruts Burirneronensts, Hall. The exterior of a pedicle-valve, This species has been regarded by Davipson, Merk and some other authors as identical vith 0. Michelini, L’Eveillé. A comparison of the American form with authentic figures of the Euro- pean species, shows a degree of difference inconsistent with the identity claimed. Burlington limestone Sageville, Illinois. For further illustration, see Geol. of Iowa, Vol. I, part ii, pl. xii, fig. 4; and pl. xx of this volume. Fig. Fig. Figs. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Figs. PLATE VI A—Continued. Orrurs Turemi, White. 14. The interior of the pedicle-valve. X 3. 15. The interior of a brachial valve which retains the bases of the crura at the extremities of the crural plates. X 3. Burlington limestone (arenaceous beds). Burlington, Towa. The specimen referred to this species, with doubt, in Palzontology of New York, Volume IV, p. 63, plate viii, fig. 2, is not O. Thiemii, and will require a different reference. Ortruis Missourrensis,* Swallow. 16, 17. Interiors of the brachial and pedicle-valves. The asymmetry of the muscular area is an ac- cidental misrepresentation. Choteau limestone. Pike county, Missouri. Orrnis Dupri, Hall. 18, 22. Views of opposite sides of the same specimen; showing the peculiar form of the shell. » 2. St. Louis group. Lebanon, Kentucky. 19. The interior of a pedicle-valve; showing the large delthyrium and strong teeth with the absence of a cardinal area. X 2. |The limitations of the muscular area are shown, but its subdivisions are not preserved. St. Louis group. Lanesville, Indiana. 20. Interior of the pedicle-valve, retaining more distinctly the subdivisions of the muscular area. X 2. Chester limestone. Litchfield, Kentucky. 21. The interior of a brachial valve ; showing the greatly thickened and elevated hinge-plate bearing the cardinal process and crural plates. 2. St. Louis group. Lanesville, Indiana. SCHIZOPHORIA, Kune. Page 211. ORTHIS SENECTUS, sp. Noy. 23. The exterior of a pedicle-valve; showing its depression over the pallial region. 24, An internal cast of the pedicle-valve ; showing the diductor and adductor scars. Clinton group. Reynale’s Basin, NV. Y. OrrHIS MULTISTRIATA, Hall. 25. An internal cast of the brachial valve of one of the original specimens; showing the subdivision of the muscular area and the diverging vascular sinuses. Lower Helderberg group. Near Clarksville, N. Y. For further illustration, see Palaeontology of New York, Volume III, plate xv, fig. 2. OrrHIs mmprREssA, Hall. (See Plate VI, fig. 31.) 26, 27. Two internal casts of the brachial valve, which retain with unusual distinctness the muscular, vascular and ovarian markings, and also the impression of the multipartite cardinal process. Chemung group. . Lawrenceville, Pennsylvania. For further illustration, see Paleontology of New York, Volume LV, plate viii, figs. 11-19. Ortuis Towensis, Hall. 29. The interior of a pedicle-valve ; showing the muscular area with a strongly thickened and elevated central adductor impression. Chemung group. Lime Creek, Iowa. See Geology of Iowa, Volume I, part ii, plate ii, figs. 4a-i. 1858. Ortuis Macraruanu, Meek.+ 28. The interior of a portion of the brachial valve, retaining at (x) the accessory adductor impressions. Chemung group. High Point, N. Y. 30 Posterior view of a specimen; showing the great disparity in the convexity of the two valves, the lower being the brachial valve. 31. Profile of another individual; showing the gibbosity of the brachial valve. Chemung group. Howard, N. Y. 32. An internal cast of a large brachial valve in which the muscular impressions are unsymmetrically developed. The cast of the cardinal process shows its subdivision on the posterior face. Chemung group. High Point, N. Y. Compare figures 5 a-k, Orthis Tulliensis, Paleontology of New York, Volume IV, plate 7. * This name was preoccupied by Orthis Missouriensis, Shumard ; Reports I and II of the Geological Survey of Missouri, 1855, part ii, page 205, plate ¢, figs. 9a, b. That species, if belonging to the Or7#iDz, should be placed under ORTHIS as restricted, or under DINORTHIS, thus leaving Orthis Missouriensis of SwALLOw under the genus RHIPODOMELLA + The species of ORTHIS— SCHIZOPHORIA, described as O propinqua, O. Tulliensis, O impressa, O. Iowensis and 0. Macfarlanii, present so many features in common that farther study and comparison should be given them to determine the actual value of the characters on which the specific distinction has been based, and whether these differences coincide with their geological relations, BRA CEHLOP OWA. Oi ivlewiel ce, Paleont.N.Y.Vol.IV.Pt.ii= Vol. VI. Creeneric [buistrations Plate VI A é E.Emmons del. i uot is i ; i x ‘ i ‘ * f + 5, ~ i 7 . Legend. A. Cardinal area. Fig. Fig. Fig. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. ow wo ee 10. PLATE VII. (Figures 1-24, 29-32 by R. P. WHITFIELD; 33-85 by F. B. MEEK; 25-28 copies.) . Cardinal process. Crura. Septum. Umbonal vault. Cast of umbonal vault. . Pedicle muscular scar. . Anterior adductors. . Posterior adductors. . Diductors. . Cardinal area, brachial valve. VA. Cardinal area, pedicle-valve. F. Foramen. . Deltidium, pedicle-valve. Delthyrium, pedicle-valve. . Deltidium, brachial valve. . Teeth. - Deatal lamelle. . Dental sockets. 4 Red Hmou. T2406 9 RHIPIDOMELLA, Ciuuerr. Page 208. (See Plates VI, VIa.) Orrnts Pecos, Marcou. . An entire specimen viewed from the brachial valve. X 2. . Profile of the same. X 2. . The interior of the pedicle-valve; showing the narrow cardinal area and the characteristic mus- cular scars. XX 2. . An enlargement of the surface ; showing the openings of the oblique tubules and minute puncte. Coal Measures. Near Springfield, Illinois. Ortuis PenniaANa, Derby. . View from the pedicle-valve. . Profile of the same specimen. ‘ . The interior of the pedicle-valve,; showing the nearly obsolete cardinal area and the strong mus- cular impressions, especially that of the pedicle-scar. . The interior of an imperfect brachial valve ; showing the cardinal process, crural bases and mus- cular impressions. - The cardinal portion of the same specimen, enlarged to show the low, thick cardinal process, the very prominent crura and the quadripartite character of the adductor area. XX 3. An enlargement of the external surface ; showing strong punctation. Coal Measures. IJtaituba, Brazil. ORTHOTICHIA, Nom. PRopos. Page 213. Orruis (?) More@antana, Derby. 11, 12. Interiors of imperfect brachial valves ; showing the cardinal process, the greatly elevated and 13. 14. 15. 16. 17. 18, 19. curved crura supported by septal plates which are produced about the sides of the muscular area. In fig. 12 are also seen the accessory adductor scars described by Dr. Dery. Section in profile of fig. 12; showing the extent of the crural plates and the elevation of the crura. The interior of a pedicle-valve, retaining the long dental lamelle and the median septum. A slightly oblique view of another interior of this valve ; showing more distinctly the elevation of the teeth and the outline of the muscular area. Coal Measures. IJtaituba, Brazil. Genus BILLINGSELLA, GEN. nov. Page 230. (See Plate VIIa, figs. 7-9.) BILLINGSELLA Peprna, Hall. The exterior of a brachial valve ; drawn from a gutta-percha impression of a natural mould. A natural cast of the interior of the brachial valve. The exterior of the pedicle-valve. A natural cast of a pedicle-valve ; showing the high cardinal area, the convex deltidium, the fill- ing of the rostral cavity and the vascular sinuses in the pallial region. Potsdam sandstone. Lake Pepin, Wisconsin. Vig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. PLATE Vil—Continued. Genus HEMIPRONITES, Panper. Page 235. HMirPronires, sp. ? . A view of the pedicle-valve, the cardinal area being in the plane of vision. The area of the op- posite valve and the deltidia of both valves are shown. X 2. 21. A cardinal view of the same specimen ; showing the characteristic contour upon which is based the separation of these forms from CLirAMBONITES. % 2. 22. A specimen cut horizontally across the umbonal region of the pedicle-valve ; showing the united dental lamelle supported by a median septum. X 2. Lower Silurian, Russia. Genus CLITAMBONITES, Panper. Page 233. CLITAMBONITES ADSCENDENS, Pander. 23. A cardinal view, giving the subpyramidal contour characterizing this genus; showing also the 28 29 30. 34 35 foramen in the deltidium. X 2. . A pedicle-valve with the apex cut away; showing the peculiar internal structure of this valve. X 2. Lower Silurian. Lussia. For further illustration, see PanprErR, Beitrage zur Geogn. russ. Reiches, plates xvii, xviii, and DE VrERNEVIL, Géologie de la Russie et des Mont. de l’Oural, plate xii, fig. 3. CLITAMBONITES (ORTHISINA) ANOMALA, Schlotheim. . A view of the pedicle-valve ; showing the great retrorsion of the apex, the high cardinal area of the pedicle-valve, and the perforated deltidium ; and also the area and deltidium of the oppo- site valve. (After pe VerNEuIL, Géol. Russ. et des Mont. de l’Oural, plate xii, fig. 20.) . The interior of the brachial valye; showing the extreme development of the cardinal area and deltidium, the latter entirely obscuring the cardinal process; the character of the muscular and vascular scars is also distinctly seen. (After Davipson.) . The interior of a pedicle-valve. (After Davrpson.) For further illustration, see pz VERNEUIL, Géol. Russ. et des Mont. de ’Oural, plate xii, fig. 2. CLITAMBONITES PLANA, Pander. . The interior of the pedicle-valve ; showing the radiating ridges beneath the spondylium. (After Davipson, Introd. Foss. Brach., plate viii, fig. 153.) Genus SCENIDIUM, Hatt. (See Plate VIIa.) Page 241. SCENIDIUM PYRAMIDALE, Hall. (See Plate VIIa, figs. 29, 30.) . View of the type-specimen ; showing the open delthyrium in each valve. X 2. A wamraling view; showing the size of the areas of the two valves and character of the delthyrium. x 2. eS Niagara group. Lockport, N. Y. ScENIDIUM INSIGNE, Hall. . A view of the brachial valve; showing the concave plate (p) in the delthyrium of the pedicle- valve. X 8. } . The opposite side of the same specimen, pedicle-valvye. X 8. . A cardinal view of conjoined valves ; showing the concave plate in the delthyrium (p), the hinge- plate (4) and the median septum (s). xX 8. . The interior of the brachial valve ; showing the elevated hinge-plate and the prominent median septum. xX 8. . The interior of a pedicle-valve with an open delthyrium. X 8. Lower Helderberg group. Near Clarksville, N. Y. ty) id CEIOPODA. @ketinnicses: Generic Thistrations PLATE VIIa. (Figures 1-12, 14-21, 25, 28-31, 33-12, 44, 46, 48-53 by E. EMMONS; 26, 27, 32 by J. M. CLARKE; 45 by G. B. Simpson; 47 by R. P. Fig. Fig. Fig. Fig. Fig. Fig. Fig. $<) Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 10. 11. 13. 14, 15. 16. WHITFIELD; 13, 22-24, 43 copies.) e Legend. D. Deltidium. s. Median septum. j. Cardinal process. s’. Lateral septum. t. Teeth. s/’. Accessory lateral septum. 1. Spondylium. a. Anterior adductor impressions. fp. Crural plates. a’. Posterior adductor impressions. e. Crura. Genus BILLINGSELLA, GEN. Nov. Page 230 Orruis (BILLINGSELLA ??) Laurentrina, Billings. . View of the brachial valve ; showing the simple plications, area and deltidium of the opposite valve. . Profile of the same specimen. . The interior of the pedicle-valve ; showing the cardinal area, teeth and covered delthyrium ; the outline of the muscular area and the median ridge. . The interior of the brachial valve, retaining the simple cardinal process and the crural plates. . The central cardinal portion of both valves, enlarged to show the character of the deltidia. On the brachial valve the deltidium is incomplete, the lateral portions not haying united, and thus exposing the posterior edge of the cardinal process. X 3. . The same parts in another specimen in which the deltidium of the brachial valve is nearly com- plete. X 3. Anticosti group. Anticosti. BiLLincGseLLa Prpina, Hall. . An internal cast of the pedicle-valve. X 3. . The interior of the same valve, from a gutta-percha impression of a natural mould ; showing the broad cardinal area, the convex deltidium, teeth, outline of the muscular area and a single pair of vascular trunks. X 3. . The interior of a brachial valve; showing the minute, linear cardinal process, and the small, slightly divergent crural plates. X 3. Potsdam sandstone. Lake Pepin, Wisconsin. For further illustration of the species, see Report of the Geological Survey of Wisconsin, Volume IV, plate i, figures 4, 5. For illustration of Orthisina orientalis, a congeneric form, see Bulle- tin Am. Mus. Nat. Hist., Volume I, No. 5, p. 144, plate xiv, fig. 6. Orruis (7?) Mycaue, Billings. The exterior of a brachial valve, from the original specimen. The interior of the same specimen, enlarged ; showing the quadripartite muscular imprint and the crural plates. There is no evidence of a cardinal process in the delthyrium. X 2. “ Point Lévis ; in the wpper part of Limestone No. 2, Quebec group.” (BILLINGS.) Orruis (??) Trrronra, Billings. . The central portion of the interior of a brachial valve, enlarged. Here, as in the preceding spe- cies, there is no trace of a cardinal process, though the quadruple division of the muscular imprint indicates that this is the brachial and not the pedicle-valye. From one of the original specimens. X 3. The exterior of the brachial valve. (After Binutnas.) “ Point Lévis ; in the wpper part of Limestone No. 2, Quebec group.” (BrLLinGs.) Genus PROTORTHIS, Gen. nov. Page 231 Prorortruts Bruitriesr, Hartt. The exterior of a pedicle-valye. X 2. The interior of a brachial yalye. X 2. The exterior of a small pedicle-valve-; showing the concave plate or spondylium which closes the delthyrium below. X 3. Fig. Fig. Fig. Fig. Fig. Figs. Fig. Fig. Fig. Figs. Fig. Fig. Fig. Fig. Fig. Fig. 18. 19. 22, 25. 26. 31. 34. 35. PLATE VII A—Continued- . A cardinal view of the same specimen. X 3. An enlargement of the surface of an internal cast. The granules may be casts of puncte on the inner layer of the shell. X 6. ~ An enlargement of the external surface of the shell; showing the sharp concentric striz# crossing the alternating plications. 6. . The central cardinal portion of the brachial yvalye; showing the broad, incuryed delthyrium with a thickened area at its base, and the absence of a cardinal process. X 6. St. John group. St. John, N. B. Prorortuis Quacornsis, Matthew. . The interior of a pedicle-valye. X 2. St. John group. Portland, N. B. For other illustration, see Trans. Royal Society of Canada, Sec. IV, 1885, plate v, figs. 20 a-c. Genus ORTHIDIUM, GEN. nov. Page 241. OrruipiuM GrmuicuLa, Billings. 93, 24. Three views of this shell. (After Bixiines.) The interior of a brachial valve; showing the simple, erect cardinal process, coalesced with the crural plates. X 4. “ Point Lévis ; in the upper part of the Limestone No. 2, Quebec group.” (Brurwes.) Sup-cenus POLYTQCSCHIA, suB-GENn. Nov. Page 239. CuirampBonires (PoLtyracuia) apicaLis, Whitfield. The cardinal portion of the pedicle-valve. The deltidium has been removed exposing the con- cave spondylium (1) supported by a median septum (s) and lateral septa (s’), The accessory lateral ridges (s’’) are also seen. X 3. . The cardinal portion of the brachial valve ; showing in profile the lateral portions of the deltidium partially enclosing the simple cardinal process. The crural plates are very divergent and nearly paraljel to the hinge-line. X 3. 29, 30. Three views of the original specimen of the species, the last showing the high cardinal area and convex deltidium. XX 3. Calciferous beds. ‘ort Cassin, Vermont. For other illustration, see Bull. American Mus. Nat. Hist., Vol. I, plate xxiv, figs. 1-5. Genus SCENIDIUM, Hatt. (See Plate VII, figs. 29-35. Page 241. OrtuHis (Scenrpium ??) Merropr, Billings. A view from the brachial valve; showing the area and foramen of the opposite valve. X 4. . The interior of the brachial valve; showing the simple cardinal process and the crural plates. The deltidial cavity is thickened transversely, and from its center a low median ridge extends forward. X 4. Hudson River group. Cincinnati, Ohio. Scenripium Hauur, Safford. . The exterior of the pedicle-valve ; showing the elevation of the beak. X 4. A cardinal view of the same specimen ; showing the area and open delthyrium on both valves, with the slender process in the bottom of the brachial delthyrium. X 4. he exterior of the brachial valve of the same specimen. X 4. . The interior of a brachial valve ; showing the triangular hinge-plate resting on the bottom of the valve, and the low median septum extending beyond the middle of the shell. The outline of the valve is more elongate than in the preceding specimen. X 4. Trenton limestone. (‘*Glade Limestone” of Sarrorp.) MWashville, Tennessee. BRA CHITOPRPOAWA. Orthide Paleont.N.Y.Vol.IV.Pt.ii= Vol. VIM. Generic Ihaistrations Plate VI. A | E.Emmons del. Phil.Astlith. PLATE VII A—Continued. Scenipium Haut, Safford, vaRrETY. Figs. 37, 38, 39. Three views of a specimen; showing the great length of the hinge, the relatively low and Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 40. 41. 42. 43. 44. 45. 51. 52. 53. 54. narrow cardinal areas and the somewhat coarser plications of the surface. X 6. Trenton horizon. Cannon Falls, Minnesota. ScENIDIUM PYRAMIDALE, Hall. (See Plate VII, figs. 29, 30.) é A view of the pedicle-valve ; showing its elevation and the character of the surface plications. X 5. A cardinal view of the same specimen ; showing the concave delthyrial plate or spondylium. X 5. A brachial valve of the same specimen. X 5. Niagara group. Lockport, N. Y. ScENIDIUM AREOLA, Quenstedt. A longitudinal section of the two valves ; showing the extension of the median plate into the cavity of the pedicle-valve. (After Davipson.) See for further information, Zeitschr. der deutsch. geolog. Gesellsch., vol. xxiii, plate viii; and Davipson, Devonian Brachiopoda, Suppl., plate iii, figs. 11-14. Genus ENTELETES, FisHer pr WaLpHEmM. Page 214. ENTELETES HEMIPLICATA, Hall. An exterior view of a young individual in which the radial plications are rudimentary. A similar view of a small example which bears a plication in the median sinus of the pedicle- valve, with a corresponding furrow on the fold of the opposite valve. “Upper Coal Measures. Kansas City, Missouri. . A similar view of a mature individual ; showing the usual character of the surface. Upper Coal Measures. JVinterset, Iowa. . A cardinal view of an individual ; showing the area and delthyrium of the pedicle-valve and the relative convexity of the two valves. . A profile of a very gibbous old individual. ~ Upper Coal Measures. Kansas City, Missouri. . A profile of the rostral portion of a pedicle-yalve ; showing the great elevation of the median and lateral septa, the edges of which are more or less broken. X 3. . A front view of the same specimen; showing the position of the septa, of which the two outer ones limit the area of muscular insertion. X 3. The interior of the rostral portion of two valvesin articulation. The median septum of the upper or pedicle-valve is broken off, but the lateral septa are retained. In the brachial valve are seen the high crural plates which are produced into strongly recurved crura. At (j) is the small, lobate cardinal process, and in the bottom of the valve a low median ridge. X 2. A profile of the same specimen ; showing the articulation of the valves and elevation of the crura. xX 2 Upper Coal Measures. Winterset, Iowa. ENTeEvLErEs Lamarcni, Fischer de Waldheim. A cardinal view of an indiyidnal ; showing the area and delthyrium of the pedicle-valve. An enlargement of the fine striz of the surface, which are shown to be tubular, as in RHIPIDOMELLA and SCHIZOPHORIA. Upper Carboniferous limestone. Mjatschkowa, Russia. For further illustration of this genus, see WAAGEN, Salt-Range Fossils, vol. i, pt. 4; also, MEEK, U. S. Geological Survey, Final Report on Nebraska, pp. 177, 178, plates vi and viii. PLATE VIIL. (Figures 1-18, 22-31 by R. P. WHITFIELD; 20, 21 by F. J. Swinton; 19 by G. B. SImpson.) = Legend. D. Deltidium, pedicle-valve. 9. Dental sockets. C. Deltidium, brachial valve. t. Teeth. A. Delthyrium. j. Cardinal process. EF. Foramen. ; a. Adductor sears. F’. Groove on delthyrium, brachial valve. r. Anterior diductor scars. A. Cardinal area : 1’, Posterior diductor scars. a. Inner portion. : a’. Outer portion. Grnus RAFINESQUINA, Gen. Nov. (See Plate VIII, figs, 1-11; Plate IX, figs. 1, 2,4; and Plate XVa, figs. 37-39.) Page 281. RAFINESQUINA INCRASSATA, Sufford* (not Hall). Fig. 1. A view of the brachial valve of a large individual; showing the area and open delthyrium of the pedicle-valve. Fig. 2. The interior of the brachial valve; showing the structure of the articulating apparatus and the muscular impressions. Fig. 3. A posterior view of the same specimen ; showing the bifurcate, incisor-shaped cardinal process, its surface sloping backward to the hinge-line, and partially covered by the deltidium. X 3. Fig. 4. A cardinal view of a portion of the hinge and area; showing the deltidia of both valves, that of the pedicle-valve having its surface distinctly grooved. X 3. Fig. 5. The internal cast of a pedicle-valve ; showing the great size of the diductor scars, and the filling of the foramen. i Trenton horizon. Platteville, Wisconsin. RaFINESQUINA ALTERNATA, Conrad. Figs. 6, 7. Two views of a specimen presenting normal external characters. Fig. 8. An enlargement of a portion of the hinge-area; showing the deltidia of both valves, and the re- tention of the foramen at maturity. X 3. Fig 9. The interior of a brachial yalye; showing the structure of the cardinal process and the adductor scars, = Fig. 10. The interior of a pedicle-valve; showing the flabellate diductor and the narrow adductor scars. Fig. 11. A posterior view of the articulating apparatus of the brachial valve. The incisor-shaped branches of the cardinal process are widely divergent, and at the bottom of the bifurcation lies a narrow callosity. The deltidium is well developed but not grooved in the middle, and the dental sockets are deeply marked. X 3. Hudson River group. Cincinnati, Ohio. For other illustrations, see Paleontology of Ohio, Vol. I, plate vii, figs. 1-3; and Paleontology of New York, Vol. I, plates xxxi and xxxia. Genus LEPTAONA, Datman. Page 276. LEPrH®NA TENUISTRIATA Sowerby (= L. rhombordalis. Wilckens). Fig. 12. The interior of a brachial valve. Figs. 13, 14. Views of opposite sides of an individual in which the foramen is retained. Hudson River group. Ozford, Ohio. Fig. 15. A portion of the hinge of a mature individual, enlarged; showing the foramen situated in front of the area, the slight development of the deltidium of the pedicle-valve, and the great size of that of the brachial valve, the latter being deeply grooved. XX 3. Hudson River group. Lebanon, Ohio. Fig. 16. An enlarged cardinal view of the central portion of the brachial valve; showing the deep groove or central depression, the callosity conforming to the contour of the cardinal apophyses. Hudson River group. Ozford, Ohio. * Since the true generic relations of the Chazy species, according to the present arrangement, is not fully ascertained, this specific name is retained for the Trenton species. Should the original Leptena incrassata, of the Chazy, prove to be a RAFINESQUINA, the Trenton form will retain the name of R. Minnesctensis, N. H. Winchell. = 7 [ NopNno Paleont. NY-Vol. IV, Ptii Db. = ) Prat) etal + Fig. Fig. Fig. Fig. Fig. g- Fig. 17. 30. 31. PLATE VI1I—Continned. LEPTZNA RHOMBOIDALIS, Wilckens. The exterior of a large pedicle-valve, which is unusually extended on the hinge-line and with acute cardinal extremities. Niagara group. Lockport, NN. Y. . An enlargement of the articulating apparatus of the brachial valve ; showing the central groove of the deltidial callosity, the lobes of the cardinal process, and the dental sockets with their low, thick inner walls (crural plates). x 3. . The interior of a brachial valve. Niagara group. Waldron, Indiana. . A view of the brachial valve; showing a foramen in the beak. . A profile view of a strongly geniculated specimen ; showing the contour of the two valves. . An enlargement of the beaks of an old individual; showing the great obliquity of the foramen in the pedicle-valve, which penetrates the substance of the shell at a considerable distance in advance of the apex; and also the perforation in the deltidium of the opposite valve. . A cardinal view of a specimen where the deltidium of the pedicle-valve has been lost or absorbed and the space filled by the callosity of the opposite valve which is perforated at the apex. . The interior of a brachial valve; showing the aspect of the cardinal process from this point of view, the character of the muscular scars, and the strong ridge at the line of geniculation of the valve. . The interior of a pedicle-valve; showing the character of the muscular impressions. . . An enlargement of the central cardinal portion of a brachial valve ; showing the deltidial callus, and the slit formed by the receding or wearing of the apical perforation. . An enlargement of the interior of the preceding specimen; showing the same features, and also the tubular opening into the rostral cavity between the divisions of the cardinal process. Lower Helderberg group. Albany and Schoharie counties, N. Y. . The exterior of an exfoliated pedicle-valve ; showing very strong undulations and the groove left by the receding of the apical foramen. . The exterior of a pedicle-valve, in which the undulations are finer and much more numerous than usual. (The L. undulata of VANUxXEM.) Corniferous limestone. Western New York. The exterior of a pedicle-valve. The interior of a brachial valve. Waverly group. Mallets’ Creek, Ohio. PLATE IX. (Figures 1-34, 36 by R. P. WHITFIELD; 35 by F. J. SwiInTON, emend.) Legend. A. Cardinal area, pedicle-valve. b. Dental sockets. Fig. Fig. Fig. Fig. Fig. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 6, § 11. 10. 12. 13. 14. a. Inner division. a’. Outer division. D. Deltidium, pedicle-valve. C. Deltidium, brachial valve. j. Cardinal process. . Median septum. Cardinal area, brachial valve. Teeth. . Adductor scars. . Diductor scars. Serko Genus STROPHOMENA, Rarinesque. Page 245. STROPHOMENA FILITEXTA, Hall. (See Plate XTa, fig. 3.) . A view from the brachial valve of a large individual. Trenton limestone. Hastern New York. . A view of the pedicle-valve; showing the great concavity of the pallial region. Trenton horizon. Mineral Point, Wisconsin. . The interior of a large brachial valve; showing the cardinal process, crural plates and undefined muscular impression. Trenton horizon. Platteville, Wisconsin. . The interior of the pedicle-valve of fig. 2; showing the covered delthyrium and the character of the muscular impressions. . The interior of a larger pedicle-valve. Trenton horizon. Mineral Point, Wisconsin. 7. Enlargements of the external (fig. 6) and internal (fig. 7) surface striz. For other illustrations, see Paleontology of New York, Vol. I, pl. xxxis, fig. 8; and Paleontology of Ohio, Vol. I, pl. vi, fig. 5. STROPHOMENA suLcATA, de Verneuil. A view of the brachial valye ; showing the area and deltidium of the opposite valve. A front view, to show the sinuate anterior margin. Hudson River group. Ohio. For other illustrations, see Paleontology of Ohio, Vol. I, plate v, fig. 5. STROPHOMENA NUTANS, James (Meek). (See Plate IXa, figs. 5-7.) A cardinal view of conjoined valves ; showing the area and deltidia. Hudson River group. Lebanon, Ohio. For other illustrations, see Paleontology of Ohio, Vol. I, plate vi, fig. 1. STROPHOMENA WINCHELLI, sp. noy. The exterior of the brachial valve ; showing its great convexity and the fine filiform radial striz of the surface. Trenton limestone. Clifton, Wisconsin. The interior of a brachial valve ; showing the slender bilobed cardinal process and the crural plates, very slightly divergent from the hinge-line. The muscular area is quadrilobate, the posterior scars being broader and having a faintly dendritic surface, the anterior pair being narrow and elongate, and striated close to the median line. The figure gives an inaccurate idea of the structure of the muscular area, which is correctly shown in figure 26, plate xx. Trenton limestone. Janesville, Wisconsin. The interior of a pedicle-valve ; showing the character of the muscular area, and the thickening about the margins of the shell. Trenton limestone. Clifton, Wisconsin. An enlargement of a somewhat exfoliated surface ; showing the distribution of puncte. 9 A SF (o) 10) Citi Ok IR A 15} idee Strophomen Plate Ix. strations . eneric Iilu G NY Vol IV, Pt.ii. Paleont. i F * } : { + 7 \ A : ; ) fi ; ; M4, t ; ; \ { Pera hy, 1 1 ; a i i) « | Tied Ve | Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. PLATE IX—Continued. SrROPHOMENA PLANUMBONA, Hall, = Strophomena rugosa, Ratinesque (de Blainville). 15. A view of the brachial valve; showing the usual form and proportions of the species. 16. 17. 18. 19. . A profile; showing the reversed convexity of the shell. 30. The interior of a brachial valve. On account of the great convexity jof this valve, the cardinal process is projected upward at an unusual angle. The interior of a pedicle-valve ; showing the usual character of the muscular markings. Hudson River group. Lebanon, Ohio. For other illustrations, see Paleontology of New York, Vol. I, plate xxxi s, fig. 4; Paleontology of Ohio, pl. vi, fig. 3; and this volume, plate ix a. STROPHOMENA SUBTENTA, Conrad. The exterior of a brachial valve; showing the oblique wrinkling of the shell about the cardinal extremities, as frequently observed in S. filitexta. Trenton limestone. Wisconsin. STROPHOMENA PLANOCONVEXA, Hall. A view of the brachial valve; showing the general external characters of the species. Hudson River group. Cincinnati, Ohio. For other illustrations, see Paleontology of Ohio, Vol. I, plate vi, fig. 2. Genus ORTHOTHETES, Panper. Page 253. OkTHOTHETES SUBPLANA, Conrad. (See Plate TXa, fig. 19.) . The interior of a pedicle-valve ; showing the muscular impressions. Niagara group. Lockport, N. Y. . A view of the brachial valve of an old example ; showing the area and deltidium of the opposite valve. . The interior of the brachial valve; showing the character of the cardinal process, the short, ab- ruptly terminating crural plates, and the edge of the deltidium which is very highly developed on this valve. . A profile ; showing the subequally convex valves. Niagara group. Waldron, Indiana. For other illustrations, see Paleontology of New York, Vol. II, plate liii; and Twenty-eighth Re- port on the New York State Museum, plate xxi. OrTHOTHETES WoonwortuHana, Hall. . A view of the brachial valve ; showing the general form of the shell and the area and deltidium of the opposite valve. . A profile of the same specimen. . An enlargement of the cardinal process; showing its bilobed character from this point of view, and the high crural plates ending abruptly at the crural bases. X 3. . A posterior view of the same parts; showing the lobation of each branch of the cardinal process, and the additional lobes on each side between the process and the dental sockets, thus making the posterior face of the divaricating process appear six-lobed. X 3. . Another anterior view of the cardinal process, in which the lobes are rather more prominent and the crural bases less pronounced. X 3. . The interior of a pedicle-valve ; showing the deltidium and muscular impressions. Lower Helderberg group. Near Clarksville, N. Y. ORTHOTHETES CHEMUNGENSIS, Conrad, var. Panpora, Billings. An enlargement of the hinge area, cardinal process, crural plates, etc., of the specimen, fig. 3, plate x; placed upon this plate by mistake. PLATE IX—Continued. ORTHOTHETES DEFORMIS, Hall. Fig. 32. Front view of an individual retaining both valves. Fig. 35. 36. Lower Helderberg group. Borst’s Mill, Schoharie county, N. Y. For illustrations of other species of the genns, see Paleontology of New York, Vol, II, plate xvii, and ibid. Vol. IV, plates ix and x; and this volume, plate xx, figs. 8, 9. Genus HIPPARIONYX, Vanuxem. Page 257. HippaRIONYyX PROXIMUS, Vanuxem. . The interior of a brachial valve of a young individual; showing the strongly bifurcated process, high vertical crural plates, short median septum, and faint muscular scars. Oriskany sandstone. Cumberland, Maryland. . The cardinal process and its adjoining parts, as obtained from a gutta-percha impression of a natural cast of the interior; natural size. This figure shows very clearly the almost complete obsolescence of the cardinal area, the marginal crenulations extending nearly to the base of the process. A natural cast of the interior of a pedicle-valve; showing the impressions of the adductor and diductor muscles. The exterior of the cardinal area of the pedicle-valve ; showing the covered delthyrium and the projecting teeth. From a gutta-percha impression. Oriskany sandstone. Albany county, N. Y. , For other illustrations, see Paleeontology of New York, Vol. III, plates Ixxxix; xc; xci, figs. 4,5; and plate xv of this volume. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Legend. 10. PLATE [Xa. (Figures 1-27 by R. P. WHITFIELD.) is) . Deltidium, pedicle-valve. p. Pedicle muscle. . Deltidium, brachial valve. a’. Anterior adductors. Teeth. a. Posterior adductors. . Dental sockets. r. Diductors. . Crural plates. y. Vascular sinuses. . Crural bases. woe TseQ Genus RAFINESQUINA, crn. Nov. Page 281. RAFINESQUINA DELTOIDEA, Conrad. . The exterior of a pedicle-valve; showing its regular convexity and deep anterior deflection, the radiating strie of subequal size, and the concentric corrugations. . Profile of the same specimen ; showing the regular convexity from umbo to anterior margin. Trenton limestone. Jacksonburg, NV. Y. . An impression of the exterior surface of the brachial valve; showing its subtriangular outline as usually developed in this species, and the flattened, scarcely concave circumbonal area. Trenton limestone. Middleville, NN. Y. This figure is from the original specimen used by Mr. Conran, and is the subject of the drawing by him reproduced in Paleeontology of New York, Vol. I, plate xxxia, fig. 3f. That figure, however, gives the valve a convexity which it does not possess. For further illustration of the species, the other figures on the plate cited may be consulted. Genus STROPHOMENA, Rarinesque (DE BLAINVILLE). Page 245, STROPHOMENA CONRADI, sp. Nov. . View from the brachial valve ; showing the reversed convexity of the valves, and the fasciculate surface striz without concentric ruge. Trenton limestone. Jacksonburg, N. Y. STROPHOMENA NUTANS, James (Meek). . The exterior of a brachial valve. . The interior of a pedicle-valve; showing the character of the muscular impressions and vascular markings. . The central cardinal portion of the brachial valve; showing the bilobed cardinal process, the curved crural plates, and the muscular impressions. X 3. Hudson River group. Oxford, Ohio. For other illustiations, see Paleontology of Ohio, Vol. I, plate vi, fig. 1. STROPHOMENA PLANUMBONA, Hall (== S. rugosa, Rafinesque). . An enlargement of the cardinal process and crural plates. X 2. . The corresponding portion of the opposite valve; showing the irregularly crenulated character of the surface of the teeth. X 2. Hudson River group. Ozford, Ohio. SrROPHOMENA FILITeExtTA, Hall. The interior of a brachial valve ; showing the cardinal process, muscular area, and the elevated median ridges of the vascular system (7). Hudson River group. Waynesville, Ohio. . The interior of a pedicle-valve ; showing the limitation of the muscular area by an elevated bor- der, which is continuous from the dental plates. . Exterior of a brachial valve ; showing the tendency to plication of the surface. . A cardinal view of a specimen retaining both valves, and showing the resupination of the shell. Fig. Fig. PLATE IXA—Continued. 14. A cardinal view of the specimen illustrated on plate ix, fig. 1. Trenton limestone. Mew York. 15. An enlarged view of the interior of a pedicle-valve; showing the vascular markings, which are rarely seen in this species.. Hudson River group. Waynesville, Ohio. STROPHOMENA ? (STROPHONELLA ?) PATENTA, Hall. (The actual relations of this species to SrropHomENA and SrROPHONELLA are not yet fully determined.) Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 16. The interior of a large pedicle-valve ; showing the muscular area. 17. The exterior of the pedicle-valve. 18. The interior of a smaller pedicle-valve. Clinton group. Reynale’s Basin, N. Y. Genus ORTHOTHETES, Panper. Page 253. ORTHOTHETES SUBPLANA, Conrad. (See Plate IX, figs. 21-29.) 19, An enlargement of the central cardinal portion of the brachial valve; showing the great develop- ment of the deltidial callosity, the rounded, somewhat unequal lobes of the cardinal process, and the thin, abrupt, nearly vertical crural plates. » 3. Niagara group. Waldron, Indiana. ORTHOLHETES IN ®QUALIS,* Hall. 20. The interior of a pedicle-yalvye. 21. A small brachial valve ; showing a tendency to a fasciculation of the strie. 22. A cardinal view of an internal cast of the brachial valve. 23. The interior of a brachial valve. In this figure the lobes of the cardinal process are not suffici- ently distinguished from the crural plates. Waverly group (Kinderhook). Burlington, Iowa. ORTHOTHETES INFLATUS, White and Whitfield. 24, A cardinal view of one of the original specimens, which is an internal cast of the brachial valve ; showing the impression of the cardinal process and adductor muscles, 25. The cardinal process, enlarged from a gutta-percha impression ; showing its appearance on the anterior face. The crural bases (x) appear very abrupt at the termination on account of the impression having been taken without the shell being first entirely removed from the matrix. Waverly group (Kinderhook). Burlington, Iowa. ORTHOTHETES DESIDERATUS, li. Sp. ~ 26. A view of the brachial valve of an internal cast; showing the muscular impressions. 27. A cardinal view of the same specimen. Waverly group. Ohio. * The reference to this species in the Report of the New York State Geologist for 1882, explanation of plate xi A (ix A) as Streptorhynchus equivalvis, is erroneous. The shell is the Orthis inequalis, Hall, Geol. Rep. of Iowa, p. 490, plate ii, figs. 6, a, Dic: BRA CHIOPODWA. Strophomenidee . Paleont. NY-VoL IV, Pt.ii. Generic TWlustrations . Platerx A. B.P. Whitfield del. Phil.Astlin. Fig. Fig. Fig. Fig. bo PLATE X. (Figures 1-14, 16, 18-23 by R. P. WHITFIELD; 15, 17 by F. B. MEEK.) Legend. D. Deltidium. j. Cardinal process. A. Cardinal area. ce. Crura. I, Umbo-lateral slopes. s. Median septum. t. Teeth. i a. Adductor scars. d. Dental lamelle. r. Diductor scars. b. Dental sockets. Genus ORTHOTHETES, Fiscoer dE WaALpHEIM. Page 283. ORTHOTHETES CHEMUNGENSIS, Courad, var. Panpora, Billings. . A view from the brachial valve; showing the cardinal area and deltidium of the oppesite valve. Corniferous limestone. Caledonia, NV. Y. . The interior of a brachial valve, drawn from a gutta-percha impression; showing the muscular area, and, imperfectly, the cardinal process. Schoharie grit. Schoharie, N. Y. . The interior of a larger brachial valve; showing with more accuracy the crural plates and the adductor scars. Piatre 1X, Fic. 30.—An enlargement of a part of the hinge area, the cardinal process, crural ’ : se ¥ a o ns p plates and muscular impressions of the preceding specimen. . The interior of a pedicle-valve ; showing the low deltidium, with unsupported teeth, the adductor and diductor scars. Corniferous limestone. Caledonia, NN. Y. . The interior of a pedicle-valve, drawn from a gutta-percha impression. Schoharie grit. Schoharie, N. Y. . An internal cast of the pedicle-valve; showing the flabellate diductors and the impression of a broad median ridge. Corniferous limestone. Western New York. OrTHOTHETES CHEMUNGENSIS, Conrad, var. ALTERNATA, Hall. . The interior of the brachial valve ; showing the characteristic cardinal process. Hamilton group. Canandaigua Lake, N. Y. ORTHOTHETES CHEMUNGENSIS, Conrad, var. ARCTOSTRIATA, Hall. . An internal cast of the pedicle-valve ; showing the impression left by the rather unusual develop- ment of the ridges surrounding the adductor scars and uniting in the median line separating the diductors. This ridge is not a septum but merely the thickening of the edges of the mus- cular scars. X 2. Hamilton group. Western New York. OrRTHOTHETES CHEMUNGENSIS, Conrad. 9. A cardinal view of a specimen; showing the irregular form of the shell, the usual width of the area, and the character of the deltidium. Chemung group. South-western New- York. For further illustration, see Paleontology of New York, Volume IV, plates ix and x. Genus DERBY A, WaaceEn. Page 261. Derpya crassa, Meek and Hayden. 10. The interior of a brachial valve; showing the cardinal process and muscular impressions. The former is represented as haying the lobes upon its edge and too acutely angular. 11. The interior of a pedicle-valye, with strong median septum dividing the muscular area, and highly developed teeth projecting into the cavity of the valve. Coal Measures. Near Winterset, lowa. Fig. Fig. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. PLATE X—Continued. Dersya Ropusra, Hall. 12. The exterior of a compressed brachial valve, in which the radial striz of the shell are strongly developed. 13. An enlargement of the cardinal process from another specimen. 14 [17 in error], 15. Profile and brachial views of a large individual; showing the external charac- ters of the species. 16. he interior of the cardinal portion of the pedicle-valve; showing the character of the muscular scars, the strong but short median septum, projecting teeth and the convex deltidiuam. The projecting tooth on the right-hand side of the figure has become double from abnormal growth. 17. The exterior of a pedicle-valve ; showing the character of the striz#, which differ in some degree from their uniformity shown in the specimen represented in figs. 14 and 15, Coal Measures. St. Clair cownty, Illinois. For other illustrations, see Paleontology of Eastern Nebraska, plates v and viii. Genus MEEKELLA, Wuire anp Sr. Joun. Page 264. MEEKELLA STRIATOCOSTATA, Cox. 18. Profile of a specimen retaining both valves; showing the great elevation of the cardinal area of the pedicle-valve. 5 19. Cardinal view of a larger individual; showing the high area, narrow deltidium, and the bases of the crural plates in the brachial valve. 20. A view of the pedicle-valve of the same specimen. 21. A cardinal view of a specimen from which the apex of the pedicle-valve has been removed to show the dental lamellae. 22. An enlargement of the cardinal process ; showing the extreme elevation of the lobes and the eru- ral plates. The central portion of the process is incorrectly represented as having three instead of two lobes. 23. A longitudinal section of the specimen represented in fig. 19; showing the extent of the dental lamelle and crural plates, to the latter of which one of the crura is attached. Coal Measures. Wear Winterset, Iowa. For other illustrations, see Transactions of the Chicago Academy of Natural Sciences, Volume I, pp. 120, 121; and Paleontology of Eastern Nebraska, plate vy. BRA CHILIOPODA. Strophomenidee Paleeont. NY.Vol.IV, Pti. Generic Illustrations . PlateX. Swinton, dith RP Whitfield, del. PLATE XI. (Figures 1-22 by R. P. WHITFIELD.) Legend. D. Deltidium, pedicle-valve. s. Median septum. C. Deltidium, brachial valve. j- Cardinal process. t. Teeth. v. Diductor scars. d. Dental lamelle. a. Anterior adductors. b. Dental sockets. a’. Posterior adductors. c. Crural plates. Genus DERBY A, Waacen. Page 261. Drreya Kroxun, Hall. Figs. 1, 2. An internal cast and gutta-percha impression of the central cardinal area, viewed from the bra- chial valve ; showing the character and extent of the muscular area, cardinal process, dental lamelle and median septum. Keokuk beds (Knobstone group). MWew Providence, Indiana. Fig. 3. An partial cast of the interior of a pedicle-valve; showing the muscular scars and impression of the median septum. Keokuk beds. Keokuk, Iowa. Derpya (?) BILOBA, Hall.* Fig. 4. A cardinal view ; showing the ventricose brachial valve and short area of the pedicle-valve. 2. Fig. 5. A view of the brachial valve; showing the bilobed contour of the shell, obdurate outline, the short cardinal area and deltidium of the opposite valve. X 2. Coal Measures. Winterset, Towa. STREPTORHYNCHUS, Kone. Page 267. STREPTORHYNCHUS Hanuianus, Derby. Fig. 6. A view from the brachial valve of an entire shell. . A posterior view of the cardinal process; showing the lobation of the posterior face, the elevated crural plates and the grooved deltidium. XX 2. Fig. 8. An enlarged view of the same parts, from above; showing also the character of the adductor im- pressions. X 2. 4 Fig. 9. The cardinal process of a larger individual; showing the grooving of the extremities of the lobes. Fig. 10. A profile of the same; showing the backward extension of the process and the great elevation of the crural plates. X 2. Fig. 11. A posterior view of thesame. X 2. Fig. 12. The cardinal process of another specimen ; showing a greater elevation and deeper bifurcation. Fig. 13. The exterior of an unsymmetrical pedicle-valve; slightly restored about the left ante-lateral margin, and showing the strongly alternating striz. Fig. 14. me interior of the same valve; showing the unsupported teeth, and the character of the muscu- ar scars. Fig. 15. The exterior of a pedicle-valve, having a plicated exterior similar to that of MpEKELLa and Sétrep- ores pectiniformis, Davidson. The shell is unsymmetrical and the outline is partially restored. Fig. 16. The interior of the same specimen ; showing the cardinal area, closed delthyrium, the projecting teeth, and the flabellate muscular impression. : Fig. 17. A view looking into the umbonal cavity of the specimen represented in fig. 14; showing the absence of dental lamella and median septum. Upper Carboniferous. Bomjardim and Itaituba, Province of Para, Brazil. a a I * Report of the New York State Geologist for 1882 (pub. 1883), explanation of plate (xi) 41, figs. 4 and 5. Fig. Fig. Fig. Fig. Fig. PLATE XI—Continued. Genus DERBYA, WAAGEN. Page 261. DerByA CorrEANA, Derby. . Cardinal view of an internal cast of the pedicle-valve; showing the cavities left by the dental lamelle and median septum. . The same specimen, viewed from above ; showing the extent of the median septum. . Cardinal view of an internal cast having a much higher area and a somewhat distorted beak. . The exterior of a high cardinal avea; showing the longitudinally grooved deltidium perforated near the lower part by a small oval foramen, which is probably accidental. From a gutta- percha impression in a natural mould. . The interior of a pedicle-valve ; showing the union of the dental lamelle with the median septum, thus forming a subapical vault. Upper Carboniferous. Itaituba, Brazil. For theforiginal illustrations of the two preceding species, see Bulletin of the Cornell University, Vol. I, No. 2 BRA CHILO PROADA. Strophomenides . Paleont. NY Vol IV Ptii Generic Illustrations . Plate XL. RP. Whitfield del Phil Astlith. PLATE XIa. (Figures 1, 2, 4-10, 12-39 by G. B. Simpson; 3 by J. C. MCCONNELL; 11 by E. EMMONS.) Legend. D. Deltidium. mf. Muscular fulera, t. Teeth. s. Median septum. j- Cardinal process. a. Adductor scars. tp. Crural plates. r. Diductor scars. b. Dental sockets. x. Cicatrix of attachment.¥' Genus STROPHOMENA, Rarinesqur (DE BLAINVILLE). (See Plates IX and IXa.) Page 245. STROPHOMENA WIHISCONSINENSIS, Whitfield. Fig. 1. Cardinal view of a specimen ; showing the broad cardinal area and deltidium of the pedicle-valve, the concayity of the brachial valve at its beak and its great convexity over the pallial region. Fig. 2. Profile of the same specimen ; showing the degree of retrorsion in the umbo of the pedicle-valve. Hudson River group. Wilmington, Illinois. For other illustrations, see Geology of Wisconsin, Vol. IV, plate xii, figs. 11-13. SPROPHOMENA FILITEXTA, Hall. (See Plate IX, figs. 1-7; and Plate IXa, figs. 10-15.) Fig. 3. The interior of a brachial valve; showing the articulating apparatus and the lobate vascular (?) ridges extending forward from the impression of the adductor muscles. Hudson River group. Richmond, Indiana. STROPHOMENA FLUCTUOSA, Billings. Fig. 4. Profile view ; showing the resupination of the lower valve and the great anterior deflection of the shell. Fig. 5. The cardinal area of the pedicle-valve, enlarged; showing the deltidium, the striated path of growth of the dental ridges, and at (¢) the pectinated margin of one of the teeth, the other not being well preserved. X 3 : Hudson River group. Spring. Valley, Minnesota. SLROPHOMENA NUTANS, James (Meek). (See Plate [Xa, figs. 5-7.) Fig. . The interior of a pedicle-valve. Fig. 7. Profile of the same specimen; showing the great elevation of the interrupted ridges surrounding the muscular area, and the median thickening on the anterior margin. Hudson River group. Weiseburgh, Indiana. lor) SrROPHOMENA suLcATA, de Verneuil. (See Plate IX, figs. 8, 9.) The interior of a brachial valve ; showing the peculiar character of the cardinal process, the strong curved crural plates, and the thickened muscular area. Hudson River group. Oxford, Ohio. Fig. 8 Genus ORTHOTHETES, Fiscuer pe WaLpHEIM. (See Plates IX and IXa.) Page 253, ORTHOTHETES SUBPLANA, Conrad. (See Plate IX, figs. 21-24.) Fig. 9. Cardinal view of an internal cast; showing the impression of the inner face of the cardinal process. Niagara group. Bridgeport, Illinois. { Fig. 10. The cardinal area of a brachial valve, enlarged. The lobes of the cardinal process are enclosed behind by a well developed deltidium, and the crural plates are short and erect, terminating abruptly. X 3. Niagara group. Waldron, Indiana. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 1. 15. PLATE XI A—Continued- An internal cast of the brachial valve. The cardinal process, enlarged. The lobes are strongly defined, the crural plates short and slightly recurving where they join the bottom of the valve, producing a thickening of the den- tal sockets. XX 3. Lower Helderberg group. Albany county, NV. Y. ORTHOTHETES PRAVA, Hall. . The interior of a brachial valve retaining the cardinal process, flabellate muscular scars and traces of vascular sinuses. Upper Devonian. Hackberry Grove, Iowa. ORTHOTHETES CHEMUNGENSIS, Conrad. (See Plate X, fig. 9.) . The cardinal process, enlarged ; showing upon its summit the edges of the lobes on the posterior face. The transverse grooves at the junction of the process with the crural plates are made to appear somewhat too abrupt. Frequently the lobes of the cardinal process are more deeply divided than in this specimen. X 24 Hamilton group. Western New York. For further illustration, see Paleontology of New York, Volume LV, plates ix and x. ORTHOTHETES CRENISTRIA, (Phillips ?) Meek. The cardinal process, enlarged ; showing the character of its inner surface and the extent of the crural plates. X 3. Waverly group. WSciotoville, Ohio. For other illustration, see Paleeontology of Ohio, Volume II, plate x, fig. 5. OrTHOTHETES LENS, White. . The exterior of a pedicle-valve. . The interior of the same valve ; showing area, deltidium, teeth and muscular impressions. . The exterior of a brachial valve. . The interior of the same valve; showing cardinal process, muscular impressions and ovarian markings. . The cardinal process of the same specimen, enlarged to show its structure. Its outer face is cov- ered by the deltidium, which conforms to the grooved surface of the lobes. The crural plates are strongly recurved at their bases about the dental sockets. X 3. Choteau limestone. Louisiana, Missouri. . A very young pedicle-valve which retains the perforation at the apex of the deltidium. X 8. . Cardinal view of the same specimen; showing the height of the area and the prominence of the deltidium. X 8. Choteau limestone. Pike county, Missouri. Genus DERBY A, WAaGEN. (See Plates X, XI and XIz.) Page 261. DerrpyA BROADHEADI, sp. Nov. Fig. 23. Cardinal view of an entire, mature individual ; showing the rugose and somewhat irregular igeek Fig. icle-valve, the more symmetrical brachial valve bearing a median sinus. 24. Profile view of the same specimen. Figs. 25 Upper Coal Measures. Kansas City, Missouri. DERBYA RUGINOSA, Sp. NOV. 27. hree views of an internal cast in chert, retaining portions of the inner lamine of the eae Both valves were of irregular growth, the brachial valve not having the median sinus of the preceding species. There are many points of similarity between this fossil and the Orthis senilis, Phillips (Streptorhynchus cr enistria. var. senilis, Davidson), which has been shown by Drrsy to have a septum in the pedicle-valve. Keokuk limestone. New Providence, Indiana. mRACHIOPRP®aWA. Strophomenidee Paleont. N.Y.Vol.IV.Pt.ii= Vol. VIII. Generic [hastrations Plate X1 A rc G.B.Simpson de! Phil.Ast.hth. i i } ; ' f : m1 in ve : i t Tye ul oF i 1 bay ' ve } a ~ ay cs : Dw i I 7 \ i j tj i ! 4 { i j y { " j i i } ‘ we Nik i ‘ i . Lf | t R i i | Vn I } ' : ' a “Be ne i a 1% of es r oe) , J i . 5 Me om) { ‘ i : ’ : : i >; ' ' ipa’ ‘ : y j 33. 34, 35. 36. 37. 38. 39. PLATE XI A—Continued. Derrpya crassa, Meek and Hayden. (See Plate X, figs. 10, 11; and Plate XI3, figs. 23, 24.) . The interior of a small brachial valve. . The cardinal process of the same specimen, enlarged ; showing the lobation at its summit and the extent of the crural plates. 3. Upper Coal Measures. Kansas City, Missouri. . The exterior of a larger pedicle-valve. 31. . The interior of a large and old pedicle-valve ; showing the median septum, the thickening about The interior of a small pedicle-valve ; showing the median septum and large muscular scars. the muscular area, due to age, and marks of vascular sinuses. Upper Coal Measures. Winterset, Iowa. The interior of a large brachial valve which is referred to this species with some doubt. The crural plates are well produced, partially enclosing arborescent scars of the adductor muscles. The valve is unusually convex for one of this species. Upper Coal Measures. Kansas City, Missouri. For other illustrations, see Paleontology of Eastern Nebraska, plate v, fig. 10, and plate viii, fig. 1. DersyA BENNETTI, sp. nov. The exterior of a pedicle-valve which retains the scar of attachment at the umbo, The opposite side of the same specimen; showing the height of the cardinal area of the pedicle- valve and the median sinus on the brachial valve. A Cranta is attached to the apex of the latter valve. Profile view of another specimen. i Cardinal view of the same; showing the high cardinal area and the lack of symmetry in the ped- icle-valve. The same specimen after having the pedicle-valve cut horizontally near the hinge. ‘The section shows the unsupported dental ridges, the tips of the grooved cardinal process, and the extray- agant development of the median septum. A similar section of the same specimen near the apex. Here the median septum is coalesced with a solid callosity filling the apical portion of the deltidial cavity. Upper Coal Measures. Kansas City, Missowri. PLATE XIs. (Figures 2-17, 20-24 by G. B. Sieson; 1, 18, 19 by E. Emons.) Legend. j. Cardinal process. ry. Rostral vault. ° . Dental lamell. dr. Dental ridges, t. Teeth. Genus DERBYA, WaaAGeEN. Page 261. (See Plates X, XI and XIa.) DERBYA, sp. indet. Big. 1. The interior of a large and very convex brachial valve; showing the cardinal process and short, vertical crural plates, from the base of which a thickened ridge extends about the muscular area. The accompanying outline profile shows the convexity of the valve. Upper Coal Measures. Kansas City, Missouri. DeRBYA CYMBULA, Sp. Noy. . Cardinal view of a large individual, somewhat incomplete at the apex ; showing the height of the area, the median groove on the surface of the deltidium, and the tendency to irregular growth in the pedicle-valve. The broken surface at the apex of the pedicle-yalvye shows evidence of the existence of a median septum. Fig. 3. View of the brachial valve of the same specimen; showing its form, contour and the character of the surface ornamentation. Figs. .4, 5. Cardinal and profile views of a small individual, probably belonging to the same species. In this specimen the irregular growth is very pronounced in both valves. Upper Coal Measures. Wear Kansas City, Missouri. Fig. bo Derspya Kaskaskrensis, McChesney. Fig. 6. The interior of an imperfect pedicle-yalve, in which the median septum unites with the dental - lamelle, forming an elongate deltidial or rostral vault, like that seen in Derbya Correana, Derby (plate xi, fig. 22). Chester limestone. Crittenden county, Kentucky. Derrpya RoBustTaA (?), Hall. (See Plate X, figs. 12-17.) Fig. 7. The interior of a brachial valve of an old shell, which probably belongs to this species. The cardinal process is much thickened and slightly irregular in its growth, the muscular area deeply excavated but not well defined, and the pallial region covered with traces of the vascular sinu- ses. The outline at the left shows the convexity of the valve. Upper Coal Measures. Winterset, Iowa. Fig. 8. The interior of a pedicle-valve, having a comparatively narrow cardinal area, a relatively small flabellate muscular impression, and a short median septum. Upper Coal Measures. Wear Kansas City, Missouri. Genus STREPTORHYNCHUS, Kine. Page 267. STREPTORHYNCHUS PELARGONATUS. Schlotheim. Fig. 9. An internal cast of the two valves; showing the position of the deltidium and dental ridges of the pedicle-valve, the inner face of the cardinal process, and the muscular impressions of the brachial valve. X 3. Figs. 10, 11, 12. Anterior, profile and cardinal views of a specimen which retains the shell; showing the contour and general external characters of the species. X 2. Fig. 13. An internal cast of the pedicle-valve ; showing the form of the muscular area, without evidence of a median septum. X 2. Fig. 14. The interior of the cardinal portion of the articulated valves ; showing the dental ridges and inner surface of the deltidium, the cardinal process, crural plates and the character of the articula- tion. xX 5. Permian Formation. Pésneck, Silesia. For further illustration, see Gritz, Dyas, plate xvi, figs. 26-84; Davipson, Permian Brachiopoda, plate ii, figs. 32-42. BRA CErOPRPOADA. Strophomenides Paleont.N.Y.Vol. IV. Pt.ii= Vol. VIII Generic Thastrations Plate X1,B. —=-= G.B.Simpson del Phil. Ast.hth. ’ 4 ‘ - \ s PLATE XIB—Continued, STREPLORHYNCHUS ULRICHI, sp. nov. Fig. 15. The interior of a pedicle-valve, referred to the genus on account of the peculiar form of the shell and the absence of median septum or dental plates. Chester limestone. Crittenden county, Kentucky. Genus DERBYA, WaaGEN. Page 261. Dera (?) COSTATULA, Sp. Nov. Fig. 16. View from the brachial valve of a small specimen, which shows the characteristic surface orna- mentation of this species. This consists of strong radial ribs alternating with fascicles of two, three or four finer striz. X 2. Fig. 17, The cardinal process of a brachial valve similar in external characters to that of the preceding specimen. X 3 Chester limestone. Crittenden county, Kentucky. Genus MEEKELLA, Waire anp Sr. Jonn. Page 264. (See Plate X, figs. 18-23.) M®EKELLA OCCIDENTALIS, Newberry. Fig. 18. View of the brachial valve of an internal cast which retains a portion of the shell over tne cardinal area of the pedicle-valve. The deltidium of this area shows the same structure as in the fol- lowing species and in the genus TrRIPLECI4, a considerable portion of the coverving between the dental ridges being flat or slightly concave, the convex ridge being confined to the middle of the plate. The apex of the brachial valve is removed, showing (imperfectly in the figure) the basal portion of the inner surface of the cardinal process. Fig. 19. An incomplete internal cast of the pedicle-valve ; showing the extension and convergence of the dental lamelle and the fine radial lines upon the surface of the plications. Both figures are from the original specimen of Orthisina occidentalis, Newberry. Upper Carboniferous limestone. Caron of Diamond River. MEEKELLA STRIATOCOSTATA, Cox. (See Plate X, figs. 18-23.) Fig. 20. Cardinal view of a large, symmetrical individual, essentially an internal cast in chert ; showing the position of the dental and crural plates. Upper Coal Measures. Winterset, Iowa. Fig. 21. Cardinal view of a distorted specimen, with an unusually high cardinal area. Fig. 22. The form of the cardinal process, from a gutta-percha impression of a natural mould. X 3. Upper Coal Measures. Lawrence county, Kansas. Genus DERBYA, Waacen. Page 261. (See Plates X, XI and XIa.) Derpya crassa, Meek and Hayden (?). (See Plate X, figs. 10, 11; and Plate XT, figs. 28-33.) Fig. 23. A portion of the internal surface of the brachial valve of Productus Nebrascensis, to which are attached several minute pedicle-valves, some of which show the presence of a broad cardinal area, deltidium and a median septum. It will be observed that most of the attached shells have their hinge-lines parallel to that of the Propuctus, though their relative positions are in- verted. X 3. Fig. 24. A further enlargement of three of these shells ; showing all the details of structure that are re- tained. These attached valves seem to be the young of some streptorhynchoid species haying a median septum in the pedicle-valve, and as Derbya crassa is the most abundant of these forms in the associated fauna, the fossils may be tentatively referred to this species. X 10. Upper Coal Measures. Near Kansas City, Missouri. PLATE XIc. (Figures 1-3, 5-9, 13, 14, 17, 18, 20-22 by R. P. WHITFIELD; 4, 10-12, 15, 16, 19, 25-28 by E. EMMONS; 23, 24 by C. E. BEECHER; 29-39 copies.) Legend. I’. Foramen, d. Dental Jamelle. ps. Deltidium. a. Anterior adductors. c, Crura. a’. Posterior adductors. j. Cardinal process. r. Diductors. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig, Fig. 6, 10. 11. Genus TRIPLECIA, Hatt. Page 269. } a : tf TRIPLECIA EXTANS, Emmons. The brachial valve of an individual of average dimensions. An anterior view of the same. . A cardinal view of the same. The delthyrium, which is here represented as open, is obscured in the specimen. Trenton limestone. Lowville, IN. Y. . The cardinal area of the pedicle-valve; showing the apical foramen and the conyex deltidial covering. : ’ Trenton limestone. Carlton Island, N. Y. . A cardinal view of a brachial valye; showing the bifurcated cardinal process extending into the matrix. 7. Anterior and posterior views of a normal individual, the latter showing the impressions of the dental plates of the pedicle-valve. X 2. Trenton limestone. Middleville, IN. Y. TRIPLECIA NUCLEUS, Hull. 9. Cardinal and profile views of a normal individual, the former showing the foramen and deltid- ium of the pedicle-valye. X 2. Trenton limestone. Middleville, NN. Y. TRIPLECIA SPIRIFEROIDES, McCoy. An internal cast of the brachial valve. A eardinal view of the same specimen; showing the impressions of the crura (c) and of the bifur- cated cardinal process. Caradoc sandstone. Worth Wales. TrreLeciaA Orvont, Meek. . The interior of the pedicle-valve ; showing the narrow area and much thickened teeth. . The exterior of a brachial valve. . Cardinal view of a specimen having the valves in conjunction ; showing the cardinal area, fora- men and deltidium. . Interior of the cardinal region of conjoined valves ; showing their mode of articulation. . Profile of the apical portion of the brachial valve ; showing the curvature of the cardinal process. . The central cardinal portion of an old and thickened brachial valve. The tips of the cardinal process and of one of the crura have been broken. . The external cardinal area of conjoined valves. XX 3. . Posterior view of the cardinal process; showing the grooves on the outer face of its branches. . Inner view of the same feature in a younger shell. Clinton group. Dayton, Ohio. For other illustrations, see Paleontology of Ohio, Volume I, plate xv, figs. 1 a-k. TRIPLECIA INSULARIS, EKichwald. . Posterior view of an internal cast of the conjoined valves; showing, in the brachial valve, the im- pressions of the antertor and posterior adductors, the crura and cardinal process, and, in the pedicle-valve, the extent of the dental lamelle. Caradoc sandstone. Ty-Isaf, Wales. BRA CELOPRPODA. Strophomenidee Paleont. N.Y.Vol.IV.Pt.ii=Vol.VII. Generic Ilhistrations Plate X1.C. ; ——| Phil-Asthth. ‘ . ‘ ‘ im ‘ ‘ ’ Nf Fig. Fig. Fig. Fig. Fig. Figs. Fig. Fig. Figs. 22. 31. 33. PLATE XIc—Countinued. TrRIPLECIA WENLOCKENSIS, Davidson. A cast of the interior of the pedicle-valve ; showing the cardinal adductor and diductor muscular scars and the impressions of the dental lamelle. Wenlock limestone. England. Genus MIMULUS, Barranpe. Page 272. Mimuxtus Watpronensis, Miller and Dyer. . View from the brachial valve of a very young individual. The shell is nearly symmetrical, and shows an open triangular delthyrium, ending in a circular apical foramen. X 5. . The opposite side of the same specimen. X 5. (From Memoirs N. Y. State Museum, Volume I, No, 1, plate iii, figs. 9, 9a.) . Cardinal view of an adult individual, the type specimen. The cardinal area shows no trace of deltidium or foramen. X 3. 27, 28. Other views of the same specimen ; showing the peculiar asymmetry of the shell. Niagara group. Waldron, Indiana. ‘Mimutus conrrarius, Barrande. 29. The exterior of the pedicle-valve ; showing the broad median sinus. . Cardinal view; showing the relative contour of the valves and the faint trace of the deltidium. Etagé E,. Tetin, Bohemia. (After BaRRaNDE, Systéme Silurien, Vol. V, pl. 9, fig. vi, A, 8.) MrimMuLus PERVERSUS, Barrande. Dorsal view of the shell; showing the sinus on the brachial valve and the uninterrupted cardinal area of the pedicle-valve. . Cardinal view of the same specimen. Etagé E,. Listice, Bohemia. (After BARRANDE, Systéme Silurien, Vol. V, pl. 1, fig. iii, c, 2.) Genus STREPTIS, Davipson. Page 274. Srreptis Grayt, Davidson. View of a brachial valve which retains the lamellar expansion at one of the growth-lines. X 4. Etagé E,. Lodenitz, Bohemia. (After BARRANDE, Systéme Silurien, pl. 83, fig. ii, 34.) 35. Brachial and anterior views; showing the asymmetry of the valves, the concentric ornamenta- tion and the perforated deltidium. X 5. 6. Cardinal view of a similar specimen. X 4. The cardinal process, broken at its tip, probably near the point of bifurcation. 39. Interiors of pedicle and brachial valves. Wenlock limestone. Dudley, England. (After Davipson, British Silurian Brachiopoda, pl. xiii, figs. 15a, 17b, 16b, 21, 19, 20.) Fig. Fig. PLATE XII. (Figures 1-5, 8-21 by RK. P. WHILEIELD; 6,7 by F. B. MEEK.) Legend. H. Hinge-line. b. Dental sockets. {D. Deltidium, pedicle-valve. t. Teeth. C. Deltidium, brachial valve. a. Anterior adductors. a. Cardinal area, outer portion. a’. Posterior adductors. j. Cardinal process. r. Diduetors. i. Lobes of cardinal process. il 2. Genus STROPHONELLA, Hatz. Page 290. STROPHONELLA ( The exterior of a brachial valve. The interior of a pedicle-valye; showing the extension of the dental lamelle along the sides of the muscular area, and the crenulations of the cardinal margin near the delthyrium. ) srrtavta, Hall. Fig, 3. An enlargement of the central portion of the brachial yalve; showing the cardinal area, its 10. 11. 13. 14. crenulated margin, and the deltidium enveloping the lower portion of the lobes of the cardinal process. In this drawing the specimen is viewed with the cardinal area nearly at right angles to the line of vision; the groove between the lobes of the cardinal process is, therefore, much foreshortened, and made to appear shallow; the crural ridges are also to be regarded as re- treating rapidly into the background. Niagara group. Waldron, Indiana. SrROPHONELLA SEMIFASCIATA, Hall. . The exterior of the concaye pedicle-valve. . An enlargement of the central portion of the area of both valves; showing the development of the deltidia and the oblique strize on the broad triangular space enclosed by the lines a, a, a. [This space should be detined by lines extending from the apex to the limit of the figure on each side, and which may be obscure in some of the figures. | Niagara group. Waldron, Indiana. SrROPHONELLA LEAVENWORTHANA, Hall. . The exterior of a brachial valye. . A profile of the same ; showing the concavity in early growth-stages, followed by great conyexity and strong geniculation. . The interior of the brachial valve; showing the crenulations of the cardinal margin, the cardinal process, slightly developed crural plates, and the adductor impressions. . The interior of the pedicle-valve; showing the crenulations of the hinge-margin, the closed del- thyrium, and the arrangement of the muscular scars. Lower Helderberg group. Albany county, NN. Y. STROPHONELLA PUNCTULIFERA, Conrad. The exterior of the brachial valve; showing the concayity in the umbonal, and conyexity in the pallial region. An internal cast of a brachiai valve ; showing the muscular imprints and the crenulations in the matrix left by the removal of the hinge. . The cardinal areas of both valves of fig. 10; showing the narrow conyex deltidium closing the delthyrium in.each valve. X 14. Lower Helderberg group. Near Clarksville, N. Y. STrROPHONELLA AMPLA, Hall. An internal cast of a pedicle-valve ; showing the muscular impressions and marks of the strongly pustulose interior surface. In the imprint left by the cardinal area are seen the crenulations of the hinge-line, and the mark of the small, linear convex deltidium. Schoharie grit. Albany county, NV. Y. The interior of a pedicle-valve in which external evidence of the deltidium is lost and the crenula- tions of the hinge extend more than half the length of the area. The margin of the area on each side of the deltidium has been broken away by the detachment of the cardinal process of the other valve. Corniferous limestone. Onondaga Valley, NN. Y. . An enlargement of the surface strite. Paleont.NY Vol IV, Pt.ii 1B RA GErOoOPRrOODA . Strophomenidee . Generic Illustrations . r TEN \ bey % j U bt r yo ; ' , i } : my { wov | A 4 v ' Huge paren! nly i + sie 1 sy ‘ i } 16. . The exterior of the pedicle-valve. . The interior of a brachial valye ; showing the deeply bifurcated cardinal process and the museu- PLATE XII—Continued. STROPHONELLA REVERSA, Hall. View from the brachial valve; showing the uninterrupted area of the pedicle-valve. lar sears. . The interior of a pedicle-valve in which the muscular and vascular markings are very strong. The cardinal area is seen to be without any trace of deltidium, and the umbonal cavity has been so completely filled by calcareous depositions about the lobes of the cardinal process that the latter have broken and remain attached (i, i,) to the pedicle-valve. . The central portion of the hinge, enlarged, from a specimen which has been somewhat weathered, thus exposing the vertical ridges which terminate in crenulations at the margin, and also show- ing the limits of the deltidia. x 2. Upper Devonian. Rockford, Iowa. STROPHONELLA C#LATA, Hall. (See Plate XV, fig. 10.) . A cast of the interior of the pedicle-valve ; showing the widely extended, crenulated hinge-line, and the very concave valve with strong muscular and vascular impressions. The points marked k, are the filling of the cavities beneath the area for receiving the extremities of the cardinal process. Chemung group. Near Elmira, N. Y. PLATE XIII. (Figures 1-27 by Rk. P. WHITFIELD; 28 by F. B. MEEK, emend.) Legend, H. Hinge-line. j. Cardinal process. D. Deltidium. a. Anterior adductors. A. Delthyrium. a’. Posterior"adductors. t. Teeth. r. Anterior diductors. b. Dental sockets. 1”, Posterior diductors. s. Median septum. o. Ovarian spaces. Genus STROPHEODONTA, Hatt. Page 254. STROPHEODONTA (BRACHYPRION) PROFUNDA, Hall. (See Plate XX, figs. 29-31.) Fig. 1. The internal cast of a pedicle-valve ; showing the muscular impressions. Fig. 2. A partial cast of a pedicle-valve with the shell removed from the upper portion ; showing the im- pression of the narrow area. The margin of the valve preserves the shell with its characteris- tic striae. Fig. 3. The central portion of a brachial valve, enlarged from a gutta-percha impression. Niagara limestone. Racine, Wisconsin. Fig. 4. The interior of a pedicle-valve having the delthyrium but partially closed, and showing the strong crenulations of the cardinal margin near the delthyrium. Fig. 5. An enlargement of the central portion of the area of the same specimen. X 2. Niagara group. Waldron, Indiana. SrropHEoponta (BRACHYPRION) vARisTRIATA, Conrad. Fig. 6. The exterior of the pedicle-valve. Fig. 7. The interior of a similar valve. Fig. 8. An enlargement of a portion of the same specimen; showing the breaking of the area by the de- tachment of the cardinal process of the opposite valve. X 3. Fig. 9. An enlargement of the central part of the area of another specimen; showing the character of the deltidium and the short row of crenulations. X 3. : Fig. 10. An enlargement of the umbonal portion of a pedicle-valve ; showing the character of the orna- mentation. X 3. Fig. 11. An enlargement of a portion of the interior of the pedicle-valve ; showing the crenulations of the hinge and the character of the muscular impressions. X 2. Fig. 12. The cardinal process and crural plates. X_2. Figs. 13, 15. Enlargements of the surface striz. Fig. 14. The exterior of a pedicle-valve. Fig. 16. An enlargement of one-half of a small pedicle-valve ; showing the fasciculate striez. Lower Helderberg group (Tentaculite and Pentamerus limestones). Schoharie Co., N.Y. « STROPHEODONTA VARISTRIATA, var. ARATA, Hall. Figs. 17, 18. Views of two pedicle-valves ; showing the strongly fasciculate surface striz. Lower Helderberg group. Becraft’s Mountain, Hudson, N. Y. STROPHEODONTA PROFUNDA ? Figs. 19, 20. Views of a specimen which has heen referred, with doubt, to this species. Clinton group. Niagara county, N. Y. STROPHEODONTA VARISTRIATA, Conrad (= S. 7mpressa, Conrad). Figs. 21, 22. Two views of this shell; showing the depressed umbo and the great convexity in the pallial region. Lower Helderberg group. Hastern New York. BRA CErOPODA. Strophomenidee Generic Ilustralions Plate XI. Riemann ith R.P Whitfield, del. Fig. Fig. Fig. Fig. PLATE Xit—Continued. STROPHEODONTA (LeprosrropHia) Becxi, Hall. 23. The interior of a pedicle-valve. The delthyrium is exposed by the removal of the deltidium, and the short dental lamelle have united, forming a minute pedicle-pit. The muscular area is bounded laterally by divergent papillose ridges which take their origin at the extremities of the dental lamelle. 24, The exterior of a brachial valve; showing the concentric undulations. Lower Helderberg group. Schoharie, N. Y. STROPHEODONTA MAGNIVENTRA. Hall . 25, 26. Natural casts of the interior of pedicle-valves ; showing the great development of the muscu- lar areas. Oriskany sandstone. Albany county, N. Y. STROPHEODONTA (LEPTOSTROPHIA) MaGNiFIcA, Hall. 27. The interior of a brachial valve, drawn from a gutta-percha impression ; showing the character of the cardinal process, which is foreshortened in the figure, the obsolescent dental sockets, the crural plates and the muscular area. Oriskany sandstone. Albany county, N. Y. 28. The interior of a pedicle-valve; showing the formation of a pedicle-pit in the delthyrium, by the union of the dental lamelle ; also the expanded, undefined muscular area. Oriskany sandstone. Cwmberland, Maryland. PLATE XIV. (Figures 1-22 by R. P. WHITFIELD.) Legend. D. Deltidium. a. Anterior adductors. j. Cardinal process. a’. Posterior adductors. s. Septum. o. Ovarian spaces. b. Dental sockets. ov Vascular sinuses. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Figs. Fig. Fig. Fig. Fig. Fig. Fig. 1, r, 1’. Diductor scars. Genus STROPHEODONTA, Hat. Page 284. STROPHEODONTA (DOUVILLINA) INZQuIsTRIATA, Hall. 2, 3. Three views, giving the external characters of the species. 4. The interior of a brachial valve. 1. 12. 13. 14. 15. 16, 18. . The central portion of the interior of the brachial valve, enlarged to show the broad, flat posterior muscular scars and the elevated anterior muscular ridges. X 3. . The interior of the pedicle-valve, enlarged to show the muscular impressions. X 2. Hamilton group. Western New York. STrROPHEODONTA DEMISssA, Conrad. . The exterior of a pedicle-valve ; showing the fasciculate character of the surface stri# near the beak. . A view from the brachial valve of a larger individual; showing no evidence of deltidium on the striated cardinal area of the pedicle-valve. . A profile view of the same. . An enlargement of the cardinal areas; showing the vertical striz and complete obsolescence of the deltidia. X 12. The interior of a brachial valve; showing the crenulated hinge-margin, the cardinal process and muscular impressions. The interior of a pedicle-valve ; showing the muscular impressions. The center of the area has been broken away by the detachment of the cardinal process. Hamilton group. Western New York. STROPHEODONTA INZQuiIRADIATA, Hall. An internal cast of the pedicle-valve ; showing the muscular impressions and vascular sinuses. An enlargement of tae umbonal portion of another cast ; showing the dendritic diductor sears, the adductors, and, at 4, the filling of the cavities oceupied by the branches of the cardinal process. Corniferous limestone. New York. STROPHEODONTA PareERsonti, Hall. The exterior of a pedicle-valve; showing, over the visceral region, the undulations of the surface between the primary radii. Corniferous limestone. Western New York. . STROPHEODONTA CoNCAVA, Hall. 17. Two views, to show the general external character of the shell. The umbonal portion of the interior of a brachial valve. From a young individual in which the cardinal process is comparatively slender and the muscular area but slightly thickened. X 13. Hamilton group. York, NV. Y. . The interior of the brachial valve ; showing the characters of the full-grown individual. . The central cardinal portion of the brachial valve of a mature individual. The lobes of the car- dinal process are of great size and deeply grooved, the crural plates in a rudimentary condition and the muscular scars much thickened. X 2. . A posterior view of the same specimen ; showing the crenulated edges of the cardinal lobes and the size of the crural plates. At x the base of the cardinal process has been excavated for the reception of the margin of the pedicle-valve. X 2. Hamilton group. Canandaigua Lake, N. Y. . The interior of a pedicle-valve ; showing a slight trace of the deltidium. . An internal cast of the pedicle-valve ; showing the adductor and diductor scars. Hamilton group. Western New York. BimA CEHrtOPOaWA. Strophomenidee Paleont. NY.VoL IV, Pt.ii. Generic Illustrations Plate XIV. PPPRTT Ee oy R.P Whitfield, del. Fig. Fig. Fig. ge Fig. Fig. Fig. Fig. Legend. y. Pedicle-valve. Lo 16. 18. 19. PLATE XV. (Figures 1-36 by R. P. WHITFIELD.) j. Cardinal process. d. Brachial valve. c. Crura, A. Cardinal area. s. Median septum. D. Deltidium. r. Diductor scars. A. Delthyrium. a. Anterior adductors. t. Teeth. a’. Posterior adductors. b. Dental sockets. Genus STROPHEODONTA, Hatt. Page 284. STROPHEODONTA CORRUGATA, Conrad. . The exterior of a pedicle-valve ; showing the corrugations along the cardinal margin, Clinton group. Western New York. SrroPHEODONTA (LEPTOSTROPHIA) PERPLANA, Conrad. . View of the brachial valve ; showing the cardinal area of the opposite valve. Corniferous limestone. Western New York. . The pedicle-valve of a smaller specimen. Hamilton group. Western New York. . The exterior of a pedicle-valve; showing the alternation in size of the striz. . An enlargement of the strie from the same specimen. Hamilton group. Vew Buffalo, Iowa. . A similar enlargement where the striz are of equal size. . The interior of a pedicle-valve ; showing the uninterrupted cardinal area and the thickened pus- tulose lateral margins of the muscular area. Hamilton group. Western New York. . The interior of a pedicle-valve retaining..similar characters. Hamilton group. New Buffalo, Iowa. . An enlargement of the interior umbonal portion of the brachial valve ; showing the cardinal pro- cess and lateral muscular ridges. X 2. Hamilton group. Canandaigua Lake, N. Y. . The cardinal process, enlarged to show the grooving of the posterior surface of the lobes for the attachment of the diductor muscles. X 3. . The cardinal areas of both valves; showing the uninterrupted striated surface. X 1}. . A longitudinal axial section of the two valves; showing the normal curvature of the shell and the position of the cardinal process. . An enlargement of the surface as left by the removal of the shell. Hamilton group. Western New York. STROPHEODONTA PERPLANA, Conrad, var. NERVOSA, Hall. . A portion of a pedicle-valve; showing the irregular character of the striz. . An enlargement of a portion of the same. . A specimen showing the wrinkled striz and extended cardinal angles. Chemung group. Steuben county, N. Y. SrropHEopoNTA (LeprosTRopPHiA) Junta, Hall. A portion of the pedicle-valve ; showing the crenulated area and partially covered delthyrium. Hamilton group. Canandaigua Lake, N. ¥. SrropHEoponta (Douvitiina) Cayura, Hall. An internal cast of the pedicle-valve ; showing the short, transverse, sharply defined muscular scar. An enlargement of tre muscular area of the same specimen. X 2. Chemung group. Steuben county, N. Y. Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 20, 23. 24, 28. 29, 31. rare 32. 33. 34, 35. 36. PLATE XV—Continned. STROPHEODONTA (PHoLmosrRopurA) NAcREA, Hall. 21, 22. -Three views giving the general external characters of the species. The interior of a brachial valve; showing the crenulated hinge-margin, cardinal process and muscular impressions. The interior of the pedicle-valve; showing the muscular impressions and partially closed delthy- sea Hamilton group. Western New York. Genus PLECTAMBONITES, Panper. (See Plate XVa.) Page 295. PLECTAMBONITES SERICEA, Sowerby. View of the brachial valve; showing the cardinal area and deltidium of the opposite valve. . The exterior of a pedicle-vyalve in which the strie alternate in size. The interior of the brachial valve ; showing the depressed visceral disk, the muscular scars and cardinal process. Au enlargement of the cardinal process ; showing its union with the crural plates and the abrupt termination of the latter. he process is simple, but on its posterior face appears trilobed from coalescence with the ends of the crural plates. 3. The interior of the pedicle-valve ; showing the divergent muscular scars. Trenton horizon. Mineral Point, Wisconsin. Genus LEPTAINISCA, BeEEcueEr. Page 300. Lrrr@®nisca concava, Hall. . The exterior of a pedicle-valve ; showing the scar at the beak, due to the attachment of the shell. The interior of the same specimen; showing the deltidium, the strong dental lamellz and the median septum. X 2. : Lower Hélderberg group. Wear Clarksville, N. Y. Genus CHRISTIANIA, Gen. nov. Page 298. CHRISTIANIA SUBQUADRATA, Hall. The interior of a brachial valve; showing the bilobed cardinal process and the quadruple ad- ductor scar, divided by high, vertical muscular walls. The interior of the pedicle-valve, with an open delthyrium, and showing the muscular walls and scars. Lower Helderberg horizon. Perry cownty, Tennessee. Genus PLECTAMBONITES, Panper. Page 295. PLECTAMBONITES TRANSVERSALIS, Dalman. The exterior of a pedicle-valve. X 2. A view from the opposite valve. X 2. : The interior of a brachial valve ; showing the elongate adductor scars. X 2. Niagara group. Lockport, N. Y. alu)) ANS a i? ©) Strophomenid G G itt © a 3 E is ee PlateXVv, ations . str eneric Ulu Paleont. NY Vol.IV Ptii. -PhilAstlith. R.P Whitfield, del. PLATE XVa. (Figures 1-18, 20-22, 24-28, 39, 40,43 by E. EMMONS; 19, 23, 34, 35, 37, 38 by G. B. Stimpson; 29, 30 by J. M. CLARKE; 41, 42 by C. E, BEECHER; 31-33 copies.) Legend. D. Deltidium (pedicle-valve). j. Cardinal process. C. Deltidium (brachial valve). e. Crura. ps. Pedicle-sheath. br. Brachial ridges. F. Foramen. a. Anterior adductor scars. t. Teeth. : a’. Posterior adductor scars. d, Dental lamellee. r. Diductor sears. 1, Spondylium. x. Searzof attachment. Genus CLITAMBONITES, PanveEr. (See Plate VII.) Page 233. Currampontres VeRNEUILI, (von Eichwald) Billings (= Hemépronites Americanus, Whitfield). Figs. 1, 2. Opposite sides of conjoined valves. Figure 2 shows that the deltidium has been lost, exposing the spondylium. Fig. 3. The interior of a pedicle-valve which does not retain the deltidium ; showing the concave delthy- rial plate or spondylium supported by a median septum. Fig. 4. A view of the same specimen, looking into the umbonal cavity of the valve. Trenton horizon. Cannon Falls, Minnesota. Figs. 5, 6. Interiors of brachial valves; showing the simple cardinal process abutting against the deltidium, and the quadripartite impression of the adductor muscles. Trenton horizon. Island of Anticosti. Figs. 7, 8. Profile and cardinal views of a small pyramidal specimen which may be a variety of this spe- cies. The deltidia of both valves are retained, that of the pedicle-valve being perforated by a large foramen. Trenton horizon. Cannon Falls, Minnesota. Genus HIPPARIONYX, VanuxemM. (See Plate IX.) Page 257. HippaRIONYX PROXIMUS, Vanuxem. Fig. 9. The interior of a pedicle-valve drawn from a gutta-percha impression of a natural mould ; show- ing the character of the cardinal area and dental lamelli, the great size of diductor scars, the margins of which are thickened and elevated by the deposition of testaceous matter. The surface of the elevations thus formed is strongly pitted. The specimen also shows the low median septum dividing the adductor impression, which in the umbonal region unites with the dental lamelle to form an apical callosity. Fig. 10. The cardinal process and crural plates of the brachial valve. The crenulations of the margin of the valve are seen to extend almost to the base of the process. Oriskany sandstone. Albany county, N. Y. Fig. 11. Profile of an internal cast of the two valves. The specimen is drawn with the brachial valve above and shows the relative convexity of the valves and the extent of the crenulated margin toward the apices. Oriskany sandstone. Cayuga, Province of Ontario. For further illustration, see Paleontology of New York, Volume III, plates 89, 90. Genus LEPTELLA, GEN. Nov. Page 293. LeErreLLA sorpipA, Billings (sp.). Figs. 12, 13. Two views of a specimen retaining both valves, and showing the outline, contour and general external characters of the species. The delthyrium of the pedicle-valve is partially closed by a convex deltidium. X 3. Fig. 14. The interior of a pedicle-valve; showing the cardinal area, deltidium and teeth, but no trace of the muscular scars is retained. X 3. PLATE XV A—Continued. Fig. 15. The interior of a brachial valve. he cardinal process consists of two independent apophyses, not coalesced with the crural plates, the latter being depressed at their origin but considerably elevated at their extremities. The visceral region is concave on either side of a broad median ridge and its surface radially striated; from its anterior margin the surface of the valve is abruptly and evenly deflected. X 5. Fig. 16. Cardinal view of the same specimen ; showing the width of the area, the posterior face of the car- dinal process and the elevation of the crural plates. X 5. These figures are from the original specimens of the species. “ Point Lévis; in the upper part of the Limestone No. 2, Quebec group.” (BILuiNGs.) Genus ANOPLIA, GEN. Nov. (See Plate XX.) © Page 309. ‘ ANOPLIA NUCLEATA, Hall. Fig. 17. Cardinal view of an internal cast of the pedicle-valve, retaining the impressions of the extremely oblique dental lamelle and the short median septum ; also showing the indistinct outline of the muscular area. X 3. Fig. 18. The interior of the brachial valve which has a close similarity to that of CHonErES. X 2. Oriskany sandstone.. Albany county, NV. Y. See also the illustrations in Paleontology of New York, Volume III, plate 91, figs. 1 a-d. Genus LEPTAINISCA, Brrcuer. Page 300. Lepr@nisoa concava, Hall. (See Plate XV, figs. 30, 31.) Fig. 19. The exterior of a pedicle-valve ; showing the contour and character of the surface. X 2. Fig. 20. The interior of a brachial valve, somewhat imperfect about the margins and cardinal process, but showing the spiral brachial] ridges and the thin median septum. X 2, Fig. 21. Cardinal view of an imperfect brachial valve preserving the character of the cardinal process, which is deeply quadrilobate. X 3. Figures 20 and 21 are from specimens illustrated by Mr. BrecuEr. Lower Helderberg group. Near Clarksville, NN. Y. LEpraNisca ADNASCENS, sp. Novy. Fig. 22. A pedicle-valve attached by nearly its entire outer surface to the interior of a valve of Orthis oblata. The specimen shows the dental lamelle and median ridge dividing the muscular area. Xx 3. Fig. 23. A specimen retaining both valves, attached to Orthis perelegans. X 4. Lower Helderberg group. Near Clarksville, N. Y. LEPTMNISCA TANGENS, Sp. Ov. Fig. 24. The exterior of a pedicle-valve with the umbo flattened from attachment, and showing the low median sinus. X 2. Fig. 25. The interior of the same specimen; showing the cicatrix of attachment (z), the deltidium and the dental lamelle X 2. Fig. 26. The exterior of a pédicle-valve in which the rugose growth has obscured the median sinus. The deep umbonal depression has been caused by attachment to some bryozoan. X 3. Figs. 27, 28. Opposite sides of a pedicle-valve attached to a twig of TREMATOPORA. X 3. Figs. 29, 30. Opposite sides of a similar valve which has been attached to a frond of FENESTELLA. X 3. These last two specimens show the bilobate exterior, the deltidium, teeth, strong dental lamelle produced about the muscular area, and the short median septum. Lower Helderberg group. Near Clarksville, N. Y. BMRA CHLOPADWA. Strophomemidee. etc. Paleont. N.Y.Vol.IV.Ptii= Vol. VI. Coneric Ilhastrations PlateXV.A. | E.Emmons del. Phil. Astlith. PLATE XVA—Continued. Genus DAVIDSONIA, Boucuarp. Page 301. Davipsonia VERNEUILIANA, Bouchard. Fig. 31. Profile of an attached specimen retaining the two valves. Figs. 32, 33. Interiors of the brachial and pedicle-valves respectively. After Davipson. Genus PLECTAMBONITES, Panper. (See Plate XV.) Page 295. PLECTAMBONITES PLICATELLA, Ulrich. Fig. 34. A group of these shells which have fallen into the sediment with their valyes attached and open. Fig. 35. One of the shells, enlarged. The surface exposed is the exterior, the concave or brachial valve showing, from compression, the outline of the cardinal process. XX 5. Hudson River group. Covington, Kentucky. Genus CHRISTIANIA, Gen. nov. Page 298. CHRISTIANIA SUBQUADRATA, Hall. (See Plate XV, figs. 32, 33.) Fig. 36. Cardinal view of the brachial valve; showing the bilobed cardinal process, widely divergent crural plates, the prominent longitudinal and transverse muscular ridges enclosing the impres- sion of the adductor muscles. X 3. Lower Helderberg group. Perry county, Tennessee. Genus RAFINESQUINA, Gn. Nov. (See Plate VIII.) Page 281. Rarinesquina ULRICHI, James. Figs. 37, 38. The exterior of two mature pedicle-valyes in which the.“primitive condition of the pedicle- passage as a tube or sheath is retained. This appears to be a normal feature of maturity in this species. X 2. Hudson River group. Covington, Kentucky. RaFINESQUINA uNICcosTATA, Meek and Worthen. Fig. 39. The interior of a brachial valve; showing the cardinal process, dental sockets.and muscular area. Hudson River group. Spring Valley, Minnesota. Genus LEPTAINA, Daman. Page 276. LEPT£ZNA RHOMBOIDALIS, Wilckens. (See Plate VIII, figs. 17-31; Plate XX, figs. 21-25.) Fig. 40. The central cardinal portion of a mature pedicle-valve ; showing the position of the inner opening of the foramen. A bristle has been drawn through the foramen to show that the passage was open at maturity. XX 3. Lower Helderberg group. Near Clarkusille, NN. Y. Figs. “41, 42. Two views of the youngest specimen obtained; much enlarged to show the structure of the pedicle-passage in its earliest observed condition. XX 10. After BrEcHER and CLARKE. Niagara group. Waldron, Indiana. LEPTHANA RHOMBOIDALIS, var. VENTRICOSA, Hall. Fig. 43. The interior of a pedicle-valve; showing the great prominence of the muscular ridges about the diductor sears and the thickened central adductor impression. Oriskany sandstone. Cumberland, Maryland. PLATE XVs. (Figures 1-9, 14-19, 21, 22, 28-30, 82-35 by G. B. SIMPsoN; 10-13, 24-26, 36, 37 by R. P. WHITFIELD; 20, 23, 27, 31 by E. EMMONS.) Bipeae Fig. 2 Fig.) 3 Figs. 4, 5. Higsmelo: Bigs vd Fig. 8 Fig. 9 Fig. °10. Fig. 11. Vig. Legend. j. Cardinal process. r. Diductor sears. a. Adductor sears. Genus STROPHEODONTA, Hatt. (See Plates XIII, XIV, XV, XX.) Page 284. SrropHEoponTA (DouviLirna) ARcuatA, Hall. . The interior of a pedicle-valve; showing the cavity in the cardinal area as left by the removal of the cardinal process, the thickened, sharply defined and elevated muscular area. . The interior of the brachial valve. . The same enlarged, to show the character of the cardinal process, the small crural plates and divergent muscular ridges. X 2. Upper Devonian, Lime Creek, Iowa. STROPHEODONTA VARIABILIS, Calvin. Opposite sides of the same specimen ; showing the contour and surface ornamentation. X 2. The interior of the brachial valve; showing the cardinal process and divergent muscular ridges. x 2 Upper Devonian. Lime Creek, Iowa. SrropHEeoponta (Douviiiina) Cayura, Hall. . The interior of a pedicle-valye ; showing the sharply defined, thickened and elevated muscular area and its subdivisions. . The interior of a brachial valve; showing the muscular ridges. Chemung group. Tioga county, Pennsylvania. SrROPHEODONTA (DOUVILLINA ?) INAZQUISTRIATA, Hall. . The interior of a pedicle-valve; showing the greatly thickened lateral margins of the muscular im- pression. Hamilton group. Canandaigua Lake, N. Y. Genus STROPHONELLA, Hatt. (See Plate XII.) Page 290. STROPHONELLA CHLATA, Hall. The interior of a brachial valve in an unusually fine state of preservation. The flabellate muscular scars have the form usual to this genus and similar to that characterizing Dovvimima. The crenulations of the hinge-line do not extend to the extremities of the cardinal area; a feature of frequent occurrence in many of the earlier species of SrropHEoponTa. The impressions of the pallial sinuses are also distinctly shown. Chemung group. Near Addison, N. Y. Genus CHONETES, Fiscuer pr WALDHEIM. (See Plate XVI.) Page 303. CuHongetes Fieminet, Norwood and Pratten. The interior of a pedicle-valve; showing the character of the muscular scars and the internal openings of the spine-tubes beneath the cardinal area. X 3. Coal Measures. I/linois. Cuonetes Smirut, Norwood and Pratten. 12. The interior of a brachial valve; showing the four scars of the adductor muscles. X 2. Coal Measures. J/linois. Fig. 13. Fig. 14. Fig. 15. Fig. 16. Fig. 17. Fig. 18. Fig. 19. Fig. 20. Fig. 21. Fig. 22 Fig. 23. Fig. 24. Fig. | 25. PLATE XVsB—Continued. CuHonetEs Amazonica, Derby. An enlargement of an internal cast of the pedicle-valve, which retains the filling of the spine-tubes crossing the cavity left by the removal of the cardinal portion of the valve. X 3. Coal Measures. Rio Tapajos, Brazil. Genus CHONOSTROPHIA, Gen. nov. (See Plate XVI.) Page 310. CHoNOstROPHIA HELDERBERGIA, sp. nov. A specimen in which the valves are opened, exposing their internal surfaces. The shell may have been somewhat flattened in fossilization, but still shows the reversal of the relative convexity of the valves, the cardinal area, teeth and faint median septum of the pedicle-valve and the finely lineate surface. The cardinal process is not retained with sufficient distinctness to permit its accurate delineation. Lower Helderberg group. Near Clarksville, N. Y. CHONOSTROPHIA REVERSA, Whitfield. The exterior of a pedicle-vyalve ; showing ifs gentle concavity and fasciculate ornamentaticn. X 2. Corniferous limestone. Delaware, Ohio. The exterior of a pedicle-valve which retains the cardinal spines. X 2. The interior af a brachial valve ; showing the contour of the shell and retaining the cardinal pro- cess. X 2. Upper Helderberg group. Cayuga, Ontario, An enlargement of the cardinal process and crural plates. The former is bilobed but short, and terminates abruptly at the base. The crural plates are also quite short and have a slightly sin- uous curvature. X 6. An enlargement of the surface striz ; showing their fasciculate grouping. X 6. Corniferous limestone. Delaware, Ohio. Genus CHONOPECTUS, Gen. Novy. (See Plate XVI.) Page 312. CHonoprctus Fiscuert, Norwood and Pratten. _ The exterior of a pedicle-valve which retains the reticulate surface ornamentation and a large scar of attachment. X 2. In strata referred to the age of the Waverly group. Warren, Pennsylvania. A jpedicle-valve having the normal proportions of the species, and showing a few spine-bases on the cardinal margin. The reticulate surface markings, as on this specimen, do not usually ex- tend over the pallial region, which is covered by exceedingly fine, often irreguiar radiating strie. . Posterior view of the umbonal region in the same specimen, enlarged to show character of the cicatrix. X 2. A small pedicle-valve, retaining the cardinal spines and showing, over the body of the shell, some divergent impressions which may be of vascular origin. Yellow sandstones. Burlington, Iowa. Genus STROPHALOSIA, Kine. (See Plates XVI, XVII, XVIIa.) Page 314. STROPHALOSIA TRUNCATA, Hall. An internal cast of a pedicle-valve ; showing the muscular impressions; enlarged. The interior of a pedicle-valve ; enlarged. Fig. 26. The exterior of a pedicle-valve ; showing the spiniferous surface ; enlarged. Marcellus shales. New York. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 27. 28. 29. 30. 32, 33. 34. 36. 37. PLATE XVze—Continued. STROPHALOSIA RADICANS, Winchell. A pedicle-valve, attached by its entire outer surface and spines to a FisruLiporRa. X 2. A pedicle-valve, situated in a cavity among the polypites of Acervulavia Davidsoni. There isa slight attachment by the apex of the valve, but fixation is mainly effected by the spines, those on the cardinal margin creeping along the surface of a polypite, and several of those which are on the body of the valve crossing the cavity, their extremities being somewhat obscured by the matrix of the specimen. ‘These latter spines appear to increase slightly in diameter from the surface of the shell outward, and their surface is marked with fine concentric annulations. X 3. The calyx of a single polypite of Acervularia Davidsoni, to which is attached a pedicle-valve of this species; its adherent spines running between the septa of the coral. X 3. An attached specimen, which retains the concave brachial valve in position, and shows the cardinal areas and deltidia of both valves. X 3. Hamilton group. Little Traverse Bay, Michigan. STROPHALOSIA HysTRIcuLA, Hall. (See Plate XVII, figs. 29, 30.) . An internal cast of a pedicle-valve, which shows the scar of attachment and impressions of the bases of spines over the body of the shell. X 3. Chemung group. Conewango, N. Y. STROPHALOSIA SCINTILLA, Beecher. A specimen retaining both valves, attached to the surface of Spirifer Marionensis. This specimen shows no trace of spines. X 6. | Another specimen which retains both valves, attached to a brachial valve of Productella pyzidata. The spines about the margin should have been represented as belonging to the lower, not to the upper (brachial) valve. X 6. The interior of a pedicle-valve attached to the surface of Syringothyris Hannibalensis ; showing the few short spines which characterize the species. X 4 Choteau limestone. Pike county, Missouri." STROPHALOSIA, sp. ? . A very small specimen attached to Spirifer Marionensis. This specimen is peculiar in showing spines on the surface of the brachial valve. It occurs in association with S. scintilla, and it may possibly prove the young of that species. X 8. SrROPHALOSIA CORNELLIANA, Derby. Posterior portion of the interior of the pedicle-valve ; showing the area, deltidium, teeth and mus- cular scars. X 3. The interior of an imperfect brachial valve which retains the cardinal process, and shows the muscular scars and brachial impressions. X 3 Coal Measures. Bomjardim, Brazil. BRA CHIOPOWDWA. Strophomenidee and Productidee . Palesont. N.Y.Vol. IV. Pt.ii= Vol. VII. Generic Lhustratons Plate XVB. G.B.Simpson del Phil-Ast.ith. i ’ rl . ‘ q s . z . bo ‘ w ‘ i - ‘ | ‘ \ rm ‘ 3 fi ‘ 3 < * . . : ‘ 9 ‘ : ‘ (2) Fig. 3. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. ite) PLATE XVI. (Figures 1-16, 18-22, 24-30, 32-44 by R. P. WHITFIELD ; 17, 31 by F. B. MEEK; 23 copy.) Legend. D. Deltidium, pedicle-valve. j. Cardinal process. C. Deltidium, brachial valve. a. Anterior adductors. st. Cardinal tubes. a’. Posterior adductors. t. Teeth. vr. Anterior diductors. b. Dental sockets. . 1’. Posterior diductors. s. Septum. vy. Brachial ridges. Genus CHONETHES, Fiscuer pr WaALDHEM. (See Plate X Vz.) Page 303. CHONETES coRNUTA, Hall. . A view of the pedicle-valve. X 2. Clinton group. Sodus Bay, N. Y. CHONETES SETIGERA, Hall. . A view of the pedicle-valve. X 2. Waverly group. Penfield, Ohio. Pedicle-valve of a larger specimen with finer strive. X 2. . An enlargement of the surface striz of this specimen. Marcellus shales. Near Caledonia, NN. Y. CHONETES scrtuLa, Hall. A pedicle-valve, with somewhat more circular outline and longer cardinal spines than usual. X 2. . A view of the brachial valve; showing the cardinal area and deltidium. . The interior of a brachial valye; showing the structure of the cardinal process and the faint brachial ridges. X 2. . The interior of the pedicle-valve; showing the cardinal area and teeth. X 2. Hamilton group. Canandaigua Lake, N. Y. . An enlargement of the cardinal portion of the valves; showing the hollow spines and the curving course of the spine-tubes through the substance of the cardinal area of the pedicle-valve. X 8. Hamilton group. Western New York. . An internal cast of the pedicle-valye, retaining the filling of the spine-tubes and showing their convergence toward the beak before reaching the upper margin of the area. X 8 Chemung group. Cattaraugus county, NN. Y. CHONETES mMucRONATA, Hall. . A pedicle-valve with very coarse plications and apparently destitute of spines. XX 2. . A pedicle-valve with long, extremely divergent spines. X 2. Marcellus shales. West Avon, N. Y. CHONETES ACUTIRADIATA, Hall. . The pedicle-valve. Corniferous limestone. Williamsville, N. Y. Cuonetes Loeant, Norwood and Pratten, var. Aurora, Hall. . Pedicle-valve, enlarged to show the fine concentric strix. X 3. An enlargement of the surface. Tully limestone. Tully, NN. Y. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Figs. 13. 29. 14. 15. 35, 17. 31. PLATE XVI—Continued. CHONETES coRoNnatTs, Conrad. . A view of the brachial valve ; showing the cardinal area and deltidium. . A pedicle-valve with unusually strong concentric growth-lines. Hamilton group. Darien, N. Y. . The interior of a brachial valve; showing the cardinal process, muscular scars and brachial g ridges. Hamilton group. York, N. Y. . The interior of another brachial valve; showing more distinctly the quadripartite character of the cardinal process. . The interior of a pedicle-valve ; showing the cardinal area, teeth and muscular scars. Hamilton group. Western New York. Genus STROPHALOSIA, Kine. (See Plates XVz, XVII, XVIIa.) Page 314. SrroPpHALOSIA MuURICATA, Hall. . The exterior of the pedicle-valve, from a gutta-percha impression of a natural mould; showing the short spines on the surface. . Two views of a pedicle-valve ; showing the cicatrix of attachment. . The interior of a brachial valve, from a gutta-percha impression; showing the cardinal process, brachial ridges and median septum. . An internal cast of the pedicle-valve ; showing the muscular impressions. . An enlargement of the muscular scars restored from several internal casts of the pedicle-valve. Chemung group. Meadville, Pennsylvania. Genus CHONOSTROPHIA, Gen. nov. (See Plate XVs.) Page 310. CHONOSTROPHIA COMPLANATA, Hall. The interior of the pedicle-valve from a gutta-percha impression ; showing the reversed convexity of the shell, the flabellate muscular area, conspicuous median septum, and the cardinal spines. Another interior of a similar valye in which the cardinal spines are apparently absent. Oriskany sandstone. Albany county, NN. Y. Genus CHONETES, FiscHER Dr WaALDHEIM. Page 303. CHONETES HEMISPHARICA, Hall. A view of the pedicle-valve; showing its great convexity. Schoharie grit. Albany county, NN. Y. CHONETES ARCUATA, Hall. Profile of a pedicle-valve, from which the radiating striae have been accidentally omitted in litho- graphing. : 36. Two views of an internal cast of the pedicle-valve ; showing the muscular impressions and the crenulation of the cardinal area, caused by the casts of the spine-tubes. Corniferous limestone. Near Williamsville, N. Y. Genus CHONOPECTUS, GEN. Nov. (See Plate XVz.) Page 312. CHonoprectus FiscHert, Norwood and Pratten. The exterior of a pedicle-valve; showing the concentrically reticulate surface. An enlargement of the surface ; showing the double series of concentric wrinkles crossing the fine radiating striz. Yellow sandstones. Burlington, Iowa. RA GCEHrOPODA. Productidee Paleont. NY VoL. IV, Pt.ii. Generic Illustrations . . Plate XVI. iq RY as AUN Ath \ Nh PhilAstlith, R.P Whitfield, del. i Figs. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 20, 23. 28. 34. 39. 41. 43. 37. Genus CHONETES, Fiscorr pr WaALpDHEIM. CHONETES VERNEUILIANA, Norwood and Pratten. 21. Two views; showing the strong median constriction. X 2. Coal Measures CHONETES MESOLOBA, Norwood and Pratten. . A pedicle-valve ; showing Coal Measures CHONETES CONCENTRICA, de Koninck. A species in which the surface.is covered with strong concentric wrinkles. PLATE XVI—Continued. Page 303. . Illinois. the median fold. X 2. . Illinois. prove congeneric with Chonetes striatella, Dalman. Lower Carboni Cuonetes Loeani, Norwood and Pratten. . The interior of a brachial valve ; showing the brachial ridges. Drawn from a gutta-percha im- pression. X 2. ferous limestone. Visé, Belgium. Waverly group. Wayne county, Ohio. See Part ii, Volume VIII, for further illustration. CHONETES DEFLECTA, Hall. The interior of a brachial valve. X 2. Hamilton group. Western New York. CHONETES LINEATA, Conrad. This species may not The interior of a pedicle-valve ; showing the area, teeth and muscular impressions. X 2. Corniferous limestone. Western New York. CHONETES SYRTALIS, Conrad (== C. coronata, Conrad). An internal cast of the brachial valve ; showing the brachial ridges. An internal cast of the pedicle-valve. An impression of the exterior of a large shell. Hamilton group. astern New York. Genus STROPHEODONTA, Hatt. (See Plates XIII, XIV, XV, XVz, XX.) STROPHEODONTA CALLOSA, Hall. Page 284. An enlarged cardinal view of the pedicle-valve ; showing the muscular impressions and crenula- tions of the area. Schoharie grit, Near Clarksville, N. Y. PLATE XVII. (Figures 1-15, 18-29, 33-46 by R. P. WHITFIELD; 16, 31, 32 by F. B. MEEK; 47-51 copies.) Legend. A. Cardinal area. j. Cardinal process. D. Deltidium, pedicle-valve. y. Brachial ridges. C. Deltidium, brachial valve. a. Anterior adductors. t. Teeth. i a’. Posterior adductors. b. Dental sockets. r. Diductors. Genus PRODUCTELLA, Hatz. Page 328, Fig. Fig. Fig. Figs. Fig. Fig. Figs. Fig. Fig. Fig. PRODUCTELLA SUBACULEATA, (Murchison) Hall. 1. The exterior of a pedicle-valve. Corniferous limestone. alls of the Ohio. 2. The interior of a brachial valve ; showing the cardinal process. Corniferous limestone. Hast Victor, NN. Y. PRODUCTELLA SPINULICOSTA, Hall. 3, 5. Two views of a pedicle-valve. Corniferous limestone. Louisville, Kentucky. 4. The exterior of a pedicle-valve. ‘ Marcellus shales. Western New York. 6. A pedicle-valve referred with doubt to this species. Yellow sandstones. Burlington, Iowa. PRODUCTELLA SHUMARDIANA, Hall. 7. A pedicle-valve with distinct spinferous coste. This figure is from one of the original specimens of the species. ; Yellow sandstones. Burlington, Iowa. PRODUCTELLA NAVICELLA, Hall. 8, 9. Views of the interior and exterior of the pedicle-valve. Hamilton group. Western New York. Genus STROPHALOSIA, Kine. ‘ (See Plates XVs, XVI.) | Page 314. STROPHALOSIA TRUNCATA, Hall. (See Plate X Vz, figs. 24-26.) 10. The interior of a brachial valve; showing the cardinal process. 11. The exterior of a brachial valve; showing the conyex umbo corresponding to the truncation of the apex of the opposite valve. X 2. 12, 13. Two views of a pedicle-valve ; showing the truncation of the beak. XX 2. Marcellus shales. Western New York. 14. An impression of the external surface of the brachial and part of the pedicle-valve ; showing the cardinal areas and minute deltidia. X 2. Hamilton group. Near Tully, NN. Y. 15. An enlargement of the cardinal process; showing its simple, uncoalesced lobes. X 6. Marcellus shales. Western New York. Grenus PRODUCTELLA, Hatt. Page 328. PRODUCTELLA SUBALATA, Hall. 16. Exterior of the pedicle-valve ; from one of the original specimens, Hamilton group. Rock Island, Iltinois. 0 BRA GHTOPRP OWA. Productidee . Paleont. NY-Vol IV, Pt.ii. Generic Hlustrations . Plate XVIL R.P. Whitfield, del, -PhilAstJith ' 4 a PLATE XV1I—Continued- PRODUCTELLA EXANTHEMATA, Hall. Fig. 17. The interior of a brachial valve ; showing the cardinal process. Hamilton group. Tinker’s Falls, N. Y. PRODUCTELLA COSTATULA, Hall. Figs. 18, 19, 20. Three views of a pedicle-valve. J Chemung group. Chemung county, N. Y. Fig. 35. The interior of a brachial valve. Above the figure is an enlargement of the cardinal process. Chemung group. Cattaraugus county, NV. Y. PRODUCTELLA DUMOSA, Hall. Fig. 21. The exterior of a pedicle-valve, showing the rounded costz with numerous spine-bases. Hamilton group. Canandaigua lake, NV. Y. PRODUCTELLA LACHRYMOSA, Conrad, var. Lima, Conrad. . A view of the pedicle-valve. A pedicle-valve with somewhat more elliptical outline. Chemung group. Cattaraugus county, NV. Y. bo Fig. Fig. bo bo ow PropuctTELLa Boyoni, Hall. Fig. 24. A pedicle-valve retaining the spines on the cardinal extremities. = Chemung group. Near (Philipsburgh) Belmont, N. Y. PRODUCTELLA SPECIOSA, Hall. Figs. 25, 26. Two views of the pedicle-valve ; showing the closely-arranged spine-bases. Chemung group. Chautauqua county, NV. Y. PRODUCTELLA STRIATULA, Hall. Fig. 27. The exterior of a pedicle-valve. Fig. 38. Cardinal view of an internal cast of the pedicle-valve; showing the mucular scars. Fig. 44. An enlargement of the external surface of the shell. Chemung group. Chautauqua county, N. Y. PRODUCTELLA HIRSUTA, Hall. Fig. 28. A pedicle-valve, retaining spines near the cardinal margin. Fig. 39. Anenlargement of the cardinal process; showing the divergence of the lobes and the edge of the grooves on their posterior face. Fig. 45. An enlargement of the external surface. Chemung group. Meadville, Pennsylvania. PRODUCTELLA HysTRicuLa, Hall. Fig 29. The interior of the brachial valve ; showing the cardinal process and the dental sockets. X 2. Fig. 30. The exterior of the pedicle-valve ; showing the fine, closely crowded spines. Chemung group. Chatauqua county, N. Y. PRODUCTELLA ARcUATA, Hall. Figs. 31, 32. Two views of a pedicle-valve. Yellow sandstones. Burlington, Iowa. PRODUCTELLA RARISPINA, Hall. Fig. 33. A pedicle-valve with a few scattered spines. Chemung group. Alleghany county, NN. Y. Fig. 34 Fig. 36 Fig. 37 Fig. 40 Fig. 41 PLATE XVII—Continued. PRODUCTELLA PYXIDATA, Hall. . The interior of a brachial valve ; showing the cardinal process, muscular scars and brachial ridges, Choteau limestone. Pike county, Missouri. PRODUCTELLA ARCTIROSTRATA, Hall. . The impression of the exterior of a brachial valve ; showing that the cardinal process is quadrilo- bate on its posterior face. Chemung group. Cattaraugus county, N. Y. PRODUCTELLA HIRSUTA, var. RECTISPINA, Hall. . The interior of a brachial valve; showing the cardinal process and slightly developed crural plates. Chemung group. Steuben county, N. Y. PRODUCTELLA oONusTA, Hall. . The interior of a brachial valve; showing cardinal process, dental sockets, muscular and brachial impressions. . An exfoliated exterior of the pedicle-valve. Chemung group. Cattaraugus county, N. Y. Figs. 42, 43. Cardinal views of internal casts of the pedicle-valve ; showing the muscular scars. Fig. 46 Chemung group. Conewango, NN. Y. . An enlargement of the surface. Genus AULOSTEGES, von HELMERSEN. Page 319. AvLostrGrs WANGENHEIMI, de Verneuil. Figs. 47, 48. Two views of a specimen; showing the highly developed cardinal area and deltidium. Fig. 49 Fig. 50 Fig. 51 . The interior of a brachial valve. (After Davipson.) Permian. Russia. Genus STROPHALOSIA, Kine. Page 314. STROPHALOSIA GERARDI, King. . View of the shell ; showing the lamellose brachial valve, cardinal areas, deltidia and the umbonal cicatrix. (After Davipson.) Permian. (?) Spiti, India. Genus PRODUCTELLA, Hatt. Page 328. PRODUCTELLA PRODUCTOIDES, Murchison. . View from the brachial valve ; showing the cardinal area and deltidia, and the marginal spines of the pedicle-valve. (After Davripson.) Upper Devonian. North Devon, England. PLATE XVIIa. (Figures 1-5, 8, 9, 11, 12, 14, 21, 25, 26 by E. EMMONS ; 6, 7, 10, 13, 15-20, 22-24 by G. B. SIMPSON.) Legend. A. Cardinal area (pedicle-valve). x. Scar of attachment. D. Deltidium (pedicle-valve). z. Posterior ridge limiting internal cavity. C. Deltidium (brachial valve). a. Anterior adductor scars. j. Cardinal process. a’. Posterior adductor scars. t. Teeth. r. Diductor scars. Genus STROPHALOSIA, Kine. (See Plates XVzB and XVII.) Page 314. STROPHALOSIA ROCKFORDENSIS, sp. Nov. Fig. 1. A view of an imperfect specimen which retains the cardinal area and deltidium of each valve. 2. Fig. 2. Cardinal view of the same specimen; showing the scar of attachment. X 2. Upper Devonian. Rockford, Iowa. STROPHALOSIA CYMBULA, sp. nov. Figs. 3, 4. Opposite sides of the same specimen ; showing the cardinal areas, deltidia and scar of attachment. Keokuk group. Lebanon, Kentucky. Figs. 8, 9. Opposite sides of a larger individual, which is somewhat crushed at the apex of the brachial valve. Keokuk group. South of Louisville, Kentucky. StropHaLosta Kroxuk, Beecher. Fig. 5. A small individual; showing the great length of the spines. Fig. 6. An attached specimen; showing deltidia, cardinal areas and adherent spines. X 2. Fig. 7. The cardinal portion of the same specimen enlarged to show the prolongation of the deltidium into a tube or sheath for the pedicle. X 4. Keokuk group. Crawfordsville, Indiana. Genus PRODUCTELLA, Hatt. (See Plate XVII.) Page 328. PRODUCTELLA, sp. (?) Fig. 10. Cardinal view of an undetermihed species, which retains the cardinal areas and deltidia of both valves and the marginal spines of the pedicle-valve. X 2. Chemung group. Greenwood, N. Y. PRODUCTELLA PYXIDATA, Hall. (See Plate XVII, fig. 34.) Fig. 14. The cardinal portion of the pedicle-valve; showing the area and teeth. X 2. Choteau limestone. Pike county, Missouri. Genus PRODUCTUS, Sowerpsy. (See Plates XVIII and XIX.) Page 321. Propuctus (MarGIniIFERA ? ?) pisstmivis, Hall (= Productella Hallana, Walcott). Fig. 11. The interior of a pedicle-valye; showing the sharp, papillose ridges or platforms diverging from _ theumbo. X 2. Fig. 12. The interior of a brachial valve which shows corresponding pitted ridges diverging from the bases of the cardinal process. This specimen also shows the remarkably extended brachial areas. X 2. Upper Devonian. Lime Creek, Iowa. Fig. Fig. Fig. Fig. Fig. Big. Fig. Fig. Figs. Fig. Figs. 13. 15. 17. 18. 19. 21. 22, PLATE XVIIA—Continued. Propuctus (Mareinirers) LasauLensis, Worthen. The interior of a brachial yalve; showing the character of the internal ridge (z), distinguishing the sub-genus MarainireRa. In this species probably occurs the most extreme development of this feature among the American productids. X 2. Upper Carboniferous. La Salle, Illinois. Propuctus maGnus, Meek and Worthen. A much flattened pedicle-valve ; showing the original length of the spines about the margins. Keokuk group. Crawfordsville, Indiana. PRODUCTUS SEMIRETICULATUS, Martin. . A portion of the interior of a brachial valve enlarged to show the structure of the brachial ridges, x 3. Upper Carboniferous. Perry county, Ohio. Cardinal view of an internal cast of the pedicle-valve ; showing the impressions of the cardinal area, the posterior and anterior adductor and the diductor muscles. The interior of a brachial valve, drawn from a gutta-percha impression of an internal cast; showing the muscular scars and the peculiar structure of the brachial areas. Coal Measures. Newcastle, Ohio. Propucrus syMMErricus, McChesney. Posterior view of the cardinal process ; showing its great elevation and strongly tripartite division, the middle lobe being produced by the coalescence of the inner members of the two principal divisions of the process. XX 3. . A portion of the brachial valve enlarged to show the structure of the brachial ridges or areas. The surface within the curved ridges is covered with irregular clusters of fine granules, which become more widely scattered in the central region about the median septum. The origin of this structure, as well as that seen in figures 16 and 18, has not been ascertained. XX 2. Upper Coal Measures. Near Kansas City, Missouri. Propuctus puncratus, Martin. (See Plate XIX, figs. 14-16.) The interior of a brachial valve of a very large and finely preserved specimen. The cardinal pro- cess shows the coalescence of the inner apophyses, the deep median groove on its surface indi- cating the original divisioninto two lobes. The muscular impressions are thickened, strongly arborescent, and show a faint division into anterior and posterior scars. Though so well pre- served, the specimen bears no trace of the brachial ridges. Upper Coal Measures. Near Kansas City, Missouri. Propuctus mQuIcosTatTus, Shumard. 23. Two views of a specimen from which the upper or visceral portion of the pedicle-valve is broken, exposing the flattened surface of the lower valve. These figures are introduced to show the peculiar mode of growth of the shell on the anterior margin, a tendency frequently exhib- ited by the Striati, and which, in its extreme development, results in an enfolded expansion or complete tube, as in P. proboscideus (PROBOSCIDELLA). Coal Measures. Nelraska. Propucrus (? AURICULATUS, Swallow.) . The exterior of a pedicle-valve, the surface of which is free of spines except along the cardinal margin. Coal Measures. Near Kansas City, Missouri. Genus STROPHALOSIA, Kine. SrROPHALOSIA SPONDYLIFORMIS, White and St. John. 25, 26. Opposite sides of a specimen; showing the cardinal areas, deltidia and scar of attachment. Coal Measures. Missouri. BRA CHIOPOUWA. Productidee. Paleont.N.Y.Vol.IV. Pt.ii= Vol. VIII. Generic Thastratons. Plate XVI. A. E.Emmons del. Phil. Ast hth. Fig. Fig. Fig. Fig. Fig. PLATE XVIII. (Figures 1-5, 14-17, 19 by R. P. WHITFIELD ; 6-13, 18 by F. B. MEEK.) Legend. j. Cardinal process. a. Anterior adductors. s. Septum. a’. Posterior adductors. v. Brachial ridges. r. Diductors. Genus PRODUCTUS, Sowersy. (See Plates XVIIA, and XIX.) Page 321. Propuctus Nrewserryi, Hall. 1. The exterior of a pedicle-valve ; showing the numerous spine-bases and retaining the spines at the cardinal extremities. Waverly sandstone. Medina, Ohio. 2. An internal cast of the united valves ; showing the muscular impressions of the brachial valve and the brachial ridges. 3. An internal cast of a pedicle-valve ; showing the adductor and diductor impressions. Waverly sandstone, Newark, Ohio. Propucrus, sp.? compare Prarrenanus, Norwood. 4. An undetermined pedicle-valve belonging to the group of the Striati. Waverly sandstone. Newark, Ohio. Propuctus, ? sp. ? 5. Profile of a pedicle-valve, with spiniferous coste. Chemung group. Cattaraugus county, N. Y. Propucrus Fiemrinet, Sowerby, var. BurLINGronensis, Hall. Figs. 6, 7, 8. Three views of a pedicle-valve. Burlington limestone. Burlington, Iowa. Propucrus MEsIALis, Hall. Figs. 9, 10. Two views of a pedicle-valve. Fig. Fig. Fig. Fig. Keokuk group. Wawvoo, Illinois. Propucrus SEMIRETICULATUS, Martin. 11. A cast of the exterior of a large brachial valve; showing the surface characters. 12. A cardinal view of the pedicle-valve. 13. A view of a specimen having the valyes united and retaining some of the cardinal spines on the pedicle-valve. Keokuk group. Warsaw, Illinois. Propucrus aurerRNatus, Norwood and Pratten. 14. A pedicle-valve with the peculiar surface markings, which are due to the exfoliation of the spine- bases. Keokuk group. Illinois. PLATE XVII—Countinued. Propuctus virratus, Hall. Fig. 15. A pedicle-valve with a somewhat exfoliated surface, but retaining the concentric growth-lines. Fig. 16. The interior of the brachial valve; showing the muscular impressions and the cardinal process, bifid on its upper surface. Fig. 17. The posterior face of the cardinal process of the valve represented in fig. 16; showing a three-fold lobation. X 3. Keokuk group. Near Keokuk, Iowa. Propuctus TENUICOSTATUS, Hall. Fig. 18. A profile view; showing the fine surface striation and the expanded anterior margins. St. Louis limestone. Milan, Illinois. Propuctrus ovatus, Hall. Fig. 19. A profile; showing the extremely produced anterior margin. Keokuk limestone. Mew Providence, Indiana. Productidee . Generic Hlustrations R.P Whitfield, del. RN N SS ~ Gy) ft S\N PhilAstlith. - fee eee =a eeetindnin s (HOR I I, AL aly) erolsibive) varmisotl Ns r tem bee ea ( lscib180 ,« -fuxtgued ~ eovilverchniioeig oe + ‘ sanutont i TOEG cabin, i a=) ie 4 CAS Wg avmgacst i ail PBS COT Mela oT eRoSotey es i ft wide Ps ; Powe te soitStit oh oe estine taut odd inovk toy ] re i ry A. aes abi Gin HSIN yAI koraci) atreut 5 Dist itaid ent Stn A Sie MstinieAL ME Sy jaa eertih p i doiilyr aa i ok, Sage fant fecO iv. surnucron eh ~ eer eriscly is t f Te aySiv' sou F : Bt WA ieee. MMAR TE Tea ins i arg IAT svliv-slothag 240, someize ga Pca “PWG Hidt tessa oisttth Io alaphivebut owt to Sates, gt Ye : iw ov lay (eidoend s to (aesirae ait 14 Of savers etal, AEB 1B Os rhode Spe, mT Lore galtato tein Lat spies ate) etry Os Aho. Woaestagl Straus, faa : tad Bie wy Wétniph 8 te tobatini salt | ti passa Leathe see eh al Tey eh OMIA StL Ee gore Init ax = eon eee ovr as ‘ m Pasise 91th Yo a8) +c edb. ES = ee Lath ee eto nei relat sally mo Su 1) -gaienials PLATE XIX. (Figures 1-23 by R. P. WHITFIELD.) Legend. j. Cardinal process. a’. Posterior adductors. a(=g). Anterior adductors. v. Brachial ridges. Genus PRODUCTUS, Sowersy. (See Plates XVII and XVIII.) Page 321. . Propuctus (MARGINIFERA) SPLENDENS, Norwood and Pratten (P. longéspinus, Sowerby). Figs. 1, 2, 3. Three views of a specimen with a few ribs and scattered spine-bases, and a nacreous shell texture. Upper Coal Measures. Winterset, Iowa. Fig. 4. The interior of a brachial valve; showing the cardinal process, muscular impressions and brachial ridges. At zz is a row of short spinules which project from the inner surface of the shell, a feature more highly developed here than in any other species observed. The submarginal ridges which characterize WAAGEN’s subgenus MarGinrrera are not highly developed in this specimen. X 2. Coal Measures. La Salle, Illinois. Propuctus NeBrascensis, Owen (= P. aspersus, McChesney). Figs. 5, 6, 7. Three views of a specimen; showing the great abundance of short spines. Coal Measures. La Salle, Illinois. Propuctus costatus, Sowerby. Fig. 8. The exterior of a pedicle-valve ; showing the general character of the specimens referred to this species in this country. Figs. 9, 10. Profiles of two individuals of different size. Fig. 11. The interior of a brachial valve, with the muscular impressions and brachial ridges. Fig. 12. An enlargement of the posterior face of the cardinal process ; showing its thickened base and trilo- bate character. X 3. : Fig. 13. An internal cast of the pedicle-valve; showing the diductor and adductor muscular scars. Coal Measures. Winterset, Towa. Propucrus puncoratus, Martin. Fig. 14. The interior of a brachial valve. Fig. 15. The cardinal process of the same specimen, viewed from the posterior side. X 3. Fig. 16. The same in profile. X 3. Coal‘Measures. Missouri. Figs. 17, 18. Two views of a pedicle-valve ; showing the spiniferous bands which form concentric annulations. Referred to this species with doubt. Coal Measures. Locality ? PRODUCTUS SEMIRETICULATUS, Martin. Fig. 19. The central portion of a brachial valve, which retains with unusual distinctness the muscular and brachial impressions. Fig. 20. Posterior view of the cardinal process ; showing the complete coalescence of the inner divisions of the two lateral lobes. X 3. Fig. 21. The inner face of the same. X 3. Fig. 22. The interior of a small brachial valve. Fig. 23. The interior of a pedicle-valve ; showing the adductor and diductor sears. Coal Measures. Jtaituba, Brazil. BRA CHIOPRPRODWA. Productidee Generic Illustrations . Plate XIX R.P. Whitfield del Phil. Astlith. PLATE XX. ORTHIS, Daman. —Page 227. ORTHIS FLABELLITES, Hall. (See Plate V, figs. 37-41.) Fig. 1. An internal cast of the pedicle-valve ; showing very distinctly the character of the muscular scar, and the simple plication of the surface. Niagara group. Hamilton, Ontario.! OrtTHIS PUNCTOSTRIATA, Hall. Page 217. Figs. 2, 3. Two views of a slightly distorted individual, retaining both valves. Fig. 4. An enlargement of the surface ; showing the rows of superficial puncte between the striz. Niagara group. - Lockport, N. Y. OrtHIS (RHIPIDOMELLA) BURLINGTONENSIS, Hall. (See Plate VIa, fig. 13.) Fig. 5. An exfoliated pedicle-valve ; showing very distinct impressions of the adductor and diductor scar. Fig. 6. Posterior view of the cardinal process and crural plates of the brachial valve. X 4. Chert of the Burlington limestone. Pike county, Missouri. Ortuis (RHIPIDOMELLA) MicHELINI, Léveillé. Fig. 7. The interior of the pedicle-valve ; after Davipson. (British Carboniferous Brachiopoda, pl. xxx, fig. 11.) Carboniferous limestone. Ayrshire. ORTHOTHETES, Fiscoer pre WALDHEIM. Page 253. ORTHOTHETES DEFORMIS, Hall, var. sINUATA, var. Nov. (See Plate IX, fig. 32.) Figs. 8, 9. Two views of a specimen; showing the distortion of the beak and the median sinus on the bra- valve, which is a characteristic feature of some species of DeRBya. Further examination will probably prove this form to be a distinct species. i Lower Helderberg group. Cumberland, Md. DERBY A, WaaGEn., Page 261. Dersya CorrEAna, Derby. (See Plate XI, figs. 18-22.) Figs. 10, 11. Two views of the umbonal portion of an internal cast ofa pedicle-valve, broken to show the filling of the umbonal cavity between the united dental plates. Fig. 10 also shows the impression of the median septum supporting these plates. X 2. Carboniferous limestone. Jtaituba, Brazil. Derpya crassa, Meek and Hayden. (See Plates X, XIs, XIc.) Figs. 12, 13. The interior of both valves of the same specimen ; showing the muscular scars, median septum and cardinal process. j Upper Coal Measures. Near Kansas City, Missouri. Fig. 14. PLATE XX—Continued. ANOPLIA, sup-GEen. Nov. Page 309. ANOPLIA NUCLEATA, Hall. (See Plate XVITa, figs. 17, 18.) Internal cast of a pedicle-valve; showing the impression of the short median septum, and the pus- tulose character of the pallial region. XX 3. Fig. 15. The interior of a brachial valve; showing the muscular impression and the pustulose surface. Fig. 16. The cardinal process is bilobed, but is probably shorter than is normal for the species. > 3. The exterior of the brachial valve; showing the smooth surface. X 3. Oriskany sandstone. Jones county, Illinois. Fig. 17. The central cardinal portion of an internal cast of the pedicle-valve ; showing the filling of the ob- lique cardinal tubes which do not penetrate to the external surface. 6. Oriskany sandstone. Columbia county, NV. Y. CHRISTIANIA. Gen. nov. Page 298. CHRISTIANIA SUBQUADRATA, Hall. (See Plates XV and XVII.) Figs. 18, 19. Two views of the pedicle-valve ; showing its elongate form, incurvature and smooth or squam- Fig. 20. Fig. 21. Fig. 21a. Fig. 22. Fig. 23. Fig. 24. ous exterior, X 2. ; The exterior of the brachial yalve, which shows the cardinal process and edges of the crural plates. X 2. Lower Helderberg group. Perry county, Tennessee. LEPTAINA, Datman. Page 276. LEPT#NA RHOMBOIDALIS, Wilckens. (See Plates VIII and XVIIa.) The deltidial area of both valves of a small individual. X 3. Longitudinal section of the two valves; showing the degree of curvature. The interior of a brachial valve ; showing very distinctly the division into anterior and posterior muscular scars. Hudson River group. Cincinnati, Ohio. The interior of a brachial valve, in which the margins of the broad posterior adductors have be- come elevated into free alate extensions. X 2. Niagara group. Waldron, Indianu. The muscular area of the brachial valve, figured on Plate VIII (fig. 31) ; enlarged from a gutta- percha impression. ‘The area is subdivided into three pairs of scars, the elongate central pair being probably accessory to the posterior adductors. X 3. Waverly group. Medina county, Ohio. Lepr#Nna ? unicosratTa, Meek and Worthen. See Plate XVIIA4, fig. 39. Figs. 25, 25a. The interior of a brachial valve and cardinal area of a pedicle-valve ; showing characters of Fig. 26 LerT mana. Hudson River group. Ohio. STROPHOMENA, RarinesQuE (DE BLAINVILLE). Page 245. SrROPHOMENA WHINCHELLI, sp. nov. (See Plate IX, fig. 12.) . An enlargement of the muscular area of the brachial valve cited ; showing the broad posterior and elongate anterior scars. X 3. Trenton limestone. Janesville, Wisconsin. BimiAA CHLOPOWA. Miscellaneous Generic Thastratons Palaont.N. Y.Vol.IV.Pt.ii= Vol. Vil Ses: Senos vewss) SSS as ry iy oF» =| Phil Ast.lith. L E.Emmons dei tian ative ol 1 I : to ; 4 all 7 , or 7 uy + ar 5 ; ; ie ‘ ; oo i 7 ah t — ‘ e en Lange i pau! 1 Sar hess Wea eel ante AS tne Fig. 27. Fig. 28. Fig. 29. Fig. 30. Fig. 31. Fig. 32. Fig 32a. Fig. 33. ‘PLATE XX—Continued. RAFINESQUINA, GEN. Nov. Page 281. RAFINESQUINA ALTERNATA, Conrad. (See Plate VIII.) The interior of a brachial valve, with sharply defined anterior and posterior adductor scars, and showing faint traces of recurving vascular sinuses. The interior of a pedicle-valve, in which the muscular scars have their normal character, Hudson River group. Cincinnati, Ohio. STROPHEODONTA, Hatt. Page 284. STROPHEODONTA PROFUNDA, Hall. (See Plate XIII, figs. 1-5.) An internal cast of the pedicle-valve ; showing the broad flabellate diductor scars, meeting in front and enclosing a rather broad pair of adductors. An enlargement of the muscular area of the brachial valve. X 13. The surface strie. X 2. Niagara limestone. Near Milwaukee, Wisconsin. STROPHOMENA, RarinesQuE (DE BLAINVILLE). Page 245. STROPHOMENA CONRADI, sp. Nov. (See Plate XIa, fig. 3.) The profile of a specimen showing only the upper or brachial valve. Outline profile of the same specimen. Trenton limestone. Trenton Falls, N. Y. 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