Bull of N.Y. Museum Bulletin 90, paleontology 14 Cephalopodaof the Beekmantown Champlain Basin, 1906

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New York State Education Department New York State useum I\L CLARKg DIREC'I'OH Bulletin 90 PALEONTOLOGY 14 CEPHALOPODA OF THE BEEKMANTOWN AND CHAZY FORMATIONS OF TH[~ CHAMPLAIN BASIN BY RUDOLF RUEDEMANN I'AGR Preface Introduction I Previous investigations Sections for reference · · Terminology 393 395 395 397 402 Order Nautiloidea 404 Species from Philipsburg, Canada 508 Synoptic taxonomy of the Cephalopoda 509 PAt.K Synoptic table of the distribution of the Cephalopoda Synoptic table of the distribution of some of the genera Relations of the cephalopod faunas to the faunas of other regions Bibliography Explanation of plates Index , 512 51 5I 27 529 605 ALBANY NE\V' YORK STATE EDUCATION DEPARTMENT 1906 Price 75 cents STATE EDUOATION DEPARTKENT Assistant Commissione.rs M.A LL.I) First Assistant Commissioner EDWARD J GOODWIN Lit,D L H D Secom! Assistant Commissioner AUGUSTUS S DOWNING M.A Third Assistant C01111J!issi('l1er HOWARD ] ROGERS Secretary to the Commissioner HARLAN H HO~NER B.A Director of State Library ED\VIN H ANDKRSON l\i.A Ph D IJL.I) Chier of DlvhdolUI HIRAM C Instruction, DE LANCEY M ELLIS New York State Education Department Science Diuision, October 12, 1905 Han Andretu S Draper Commissioner of Education l\1Y DEAR SIR: I beg to transmit herewith for publication, the manuscript of a bulletin of the State Museum entitled, The Cepha- lopoda of the Beekmantoton and C~hazy Formations of the Champlain Basin by Dr Rudolf Ruedemann, Assistant Paleontologist This work constitutes an important contribution to our knowledge of the ancient faunas of New York State and I have explained its bearings somewhat fully in my preface to the paper Very respectfully yours JOHN M CLARKE Director and Stale Geologist Approved for publication October 12, 1905 Commissioner (If Education New York State Education Department New York State Museum JOHN ]\;1 CLARKE Director Bulletin go PALEONTOLOGY 14 CEPHALOPODA OF THE BEEKMANTOWN AND CHAZY FORMATIONS OF THE CHAMPLAIN BASIN BY RUDOLF RUEDEl\1ANN PREFACE The faunas of the older New York formations have never received adequate consideration The invaluable determinations made by Prof James Hall in the first volume of the Palaeontology of N C1.V }' ork were based on the material collected chiefly from the central and western skirts of the Adirondacks during the progress of the geological survey of 1836-43 or brought together from still older collections belonging to private individuals or to the Albany Institute Although this great work laid the foundation of all our knowledge of these early faunas in America yet as the years passed on its distinguished author realized its incompleteness The Siluric region of the Lake Champlain basin was then an unopened field to the paleontologist The profusion of its fossil remains, which far exceed in abundance those of the region from which the original collections were assembled, was not recognized and it was not till the later years of Professor Hall's long life that explorations ill this basin began to reveal the inadequacy of his early work It "vas one of his unrealized purposes of this later period to revise and amplify the volume referred to Though it did not fall to him to see this important work executed yet he may be credited with having initiated the undertaking Explorations having for their end a more exact knowledge of the stratigraphy of the region were inaugurated by him and at his instance Professors J F Kemp and H P Cushing commenced their study of the geology of Essex and BEEK~iANTO\VN AND CHAZY FOR1\iATIONS OF CHA1\1PLAIN BASIN 395 INTRODUCTION I Statement of previous investigations The status of our present of the Champlain basin may be understood from the has described in his V01UY11e I of the of the data.' Hall N e70 York both two species of cephalopods from the Beekmantown From small fragments, neither nor living chamber, and one only the surface; and four frorn the Chazy Iimestone, from but one of which the siphuncle is known, from another only the surface and from the remaining two only acci- dental sections On the other hand, Billings has distinguished no less than 49 cephalopods from the Beekmantown formation of Newfoundland, Quebec and Philipsburg,' only a smali number of which have been figured" and has also added 10 species of Chazy limestone cephalopods to the five made known by Hall Barrande also has made us acquainted with six species from the Beekmantown formation of Canada and Newfoundland and Whitfield has carefully described and well illustrated an excellently pre- served upper Beekmantown limestone fauna from Fort Cassin in Vermont, but unfortunately has, under the misapprehension that the beds were of the age of the Lowville (Birdseye) limestone, compared them rather with Trenton limestone forms than with Billings's Beekmantown limestone species The same author has also de1 See bibliography at end In regard to the fauna of the Beekmantown beds at Philipsburg, Missisquoi co which lie at the northeastern terminus of Lake Champlain in the Province of Quebec, we had no desire to enter the domain of the paleon tologist of the Canadian survey in charge of the invertebrate faunas, hoping that he, having the advantage of the use uf the first collections from this locality, of Billings's types and of a thorough knowledge of the Canadian cephalopods, will himself undertake the needed revision and elaboration of the Beekmantown cephalopod fauna of this region It is specially desirable that the considerable number of species of Orthoceras, described by Billings from that locality, without figures, should be redescribed, referred to their proper genera, and abdve all figured, to make them available for comparison with those of other Beekmantown faunas We have only cited here [po 508] the cephalopod species recorded from Philipsburg by Billings and Barrande : and in the case of the species of nautiloid forms described by Hyatt, inserted the descriptions Hyatt's new -pecies of Philipsburg nautiloids have not yet been illustrated nor described in all their characters it true and therefore on the artificial of curvature of the conch; distribute a series of of average in this can not fail to observe that its fundamental criteria of as the character of the funnels or necks and the internal structure of the difficult of observation and fail so obscured that a in of are decision as to the relation of the divisions and thereafter to of cases And recoamzed, it l)le()OilrleS ~ n1"'~ "1" SQ 1"' • BEEK1\fANTOvVN AND CHAZY FOR1\fATIONS OF CHAMPLAIN IlASIN 397 Sections for reference Since the of the here described have been obtained from the shore at Valcour, south of Plattsburg, we insert here for reference a brief section of the exposures in which the cephalopods both of the upper Beekmantown and lower are found to occur more and better than in any other locality on the west shore of the lake, known to the writer A fuller discussion of the important Valcour section is necessarily deferred until the investigation of the Beekmantown and Chazy faunas has been completed The major part of this material has been jointly collected by Prof G van I ngen and the writer during the summer of 1899; a number of valuable specimens have also been obtained by Professor van Ingen during the field season of 1901, and the specimens cited from Beekmantown, Chazy and Valcour were mostly collected by the writer during the summer of 1903 The exposure of the Beekmantown beds on the Valcour shore begins about one half mile north of the 1110Uth of the Little Ausable river, in front of the farmhouse of W H Ayers (Lake View farm) and continues with some interruptions to the Valcour dock (Port Jackson) where a fault separates it from the exposures of Lower Chazy rocks, which thence continue northward around Day's point The Beekmantown beds have been provisionally distinguished as 2065 A1-A/ and the Chazy beds as 2066 B1-Bs Section of the Beekmantoum beds at Vale our in ascending order Ai is a four foot bed of hard bluish gray, gritty dolomite Strike, 30 e.; dip, SO s e A~ begins 100 feet north of end of AI" feet Bluish gray dolomite, with lenses of lighter dolomite ; the latter very fossiliferous A!, exposed about 300 feet north of A • feet This division is shaly at the base, compact, gray or black at the middle and shaly and black at the top, the whole weathering yellowish The gray portion is a mass of fossil fragments derived from crinoids, trilobites, cephalopods, gastropods and brachiopods, and contains small rounded pebbles or concretions The shaly portion at the top is a valuable depository of cephalopods (nautilicones and orthoceracones) n This A is not identical with the division A of the Beekmantown of Brainerd and Seely, nor is B, Chazy, identical with their Chazy B On the contrary the Beekmantown beds at Valcour are undoubtedly equivalent to a part of the Fort Cassin beds and therefore probably to be placed at the top of their Group D [see section on p 399] and the Chazy beds correspond to Brainerd and Seely's upper A of the Chazy feet of a purer, blue which is and contains seams of black shale bed (7 of blue at of at east end of and consists of a concealed interval from bluish limestone strata, which weather gray, about 25 feet of are barren and contain some This bed ends at the Valcour dock n, 40 W.; IS° S w 11'" 1"'1"'1110'1"'117 "",.n,:II.I''IJ-''''''' Y on ; very tossuner- coatainmg a rich fauna the Valcour furnishes other characters not obtainable the We have for these reasons and also because Schroder's is probably not sible inserted here a full descrmtion species drawn from Professor Whitfield's specimen, and from our material obtained at Valcour, Description Conch coiled nautilicone up to gf1'.lronltlc the not rl1rt .r \rtt'¥tt., · to the costae and the tachyback of the time of their appearance on the whorls to the Plectoceratidae The of the ribs in T per k j n s i even of this variety to the genus Plectoceras, Since, the Plectoceratidae are as forms in which the annular costae appear in the neanic stage and here are not observed earlier than in the stage, this form still falls within the confines of Tarphyceras, f'\11,chtt"cr Tarphyceras clarkei sp nov Plate :ua cnameer occupying one half of one volution in type specifree in gerontic age Aperture not known, by jndications from growth' lines' much advanced in dorsal region, and uniformly receding in ventral direction Cameras shallow, at- BEEK M AN TOW N AND CHA ZY FO RMATIONS OF CHA~IPLAIN BAS IN 471 taining an average depth of 4.5 mm in th e epheb ic stage Se pta quite concave, th eir concavity equa l to th e depth of th e cam eras ; sutures pass nearly straight tran sver sely, with har dly any trace of a vent ral Fi g 27 size T ar p h Yc er a sc i a r k e I sp nov Secti on o f ty pe (pl 22) Natu l o Fi g 28 F ig 2Q F ig Fi g 28- 31 Tar p h yc era s cl a r k ei sp nov Tra nsverse sec tio ns xs:olJ Ftg; Section through ad volutlo n ; fig 2Q , sectio n a t end o f 3d vol, ; fig n ing of livin g cha mb er; fig 3', se ction throu gh middl e of li vin g cha mbe r ~" i g 30, 3' se ct ion at begin- saddle in the ephebic and gerontic stages, or even a slight recession of the suture in the earl y ephebic stage upon th e abdomen ... extendof the chambers to the middle of the From the structure of the ,'~ in V p p l e tum we conclude that here the exof the chambers to their tended from the upper outer lower inner or the of the. .. during the summer of 1903 The exposure of the Beekmantown beds on the Valcour shore begins about one half mile north of the 1110Uth of the Little Ausable river, in front of the farmhouse of W H... in the of the the rate of and size-from the formation of the the islands of Montreal and Bizard.Tbe most difference between 'the two similar find to consist in the different relative width of the
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