University of the State of New York
=co
MEMOIR
New York State Museum
Frederick J. H. Merkill Director
No. 3 Vol. 3 October 1900
THE ORISKANY FAUNA OF BECRAFT MOUNTAIN COLUJVIBIA COUNTY, N. Y.
JOHN M. CLARKE M.A. Ph.D. StaU faltintoUgist
ALBANY
UNIVERSITY OF THE STATE OF NEW YORK
I goo
University of the State of New York
MEMOIR
OF THE
New York State Museum
Frederick J. H. Merrill Director
No. 3 Vol. 3 October 1900
THE ORISKANY FAUNA OF BECRAFT MOUNTAIN
COLUNIBIA COUNTY, N. Y.
JOHN M. CLARKE M.A. Ph.D. State faleontologiit
ALBANY
UNIVERSITY OF THE STATE OF NEW YORK
1900
V^
University of the State of New York
REGENTS With yean of election
1874 Akson Judd Upson L.H.D. D.D. LL.D. - - Clumcellor, Glens Falls
1892 William Oeoswell Doank D.D. LL.D. - - Vice-Chancellor, Albany 1873 Martin I. Townsend M.A. LL.D. _____ Troy
1877 Chaunoet M. Depew LL.D. _______ New York
1877 Charles E. Fitch LL.B. M.A. L.ILD. _ _ _ _ Kochester
1877 Orris H. Warren D.D. _______ Syracuse
1878 Whitklaw Reid LL.D. _______ New York
1881 William H. Watson M.A. M.D. _____ Utica
1881 Henry E. Turner ________ Lowville
1883 St Claie McKelway L.H.D. LL.D. D.C.L. _ _ _ Brooklyn
1885 Hamilton Harris Ph.D. LL.D. _____ Albany
1885 Daniel Beach Ph.D. LL.D. ______ Watkins
1888 Carroll E. Smith LL.D. ______ Syracuse
1890 Pljny T. Sexton LL.D. ______ _ Palmyra
1890 T. Guilford Smith M.A. C.E. LL.D. _ _ _ _ Buffalo
1893 Lewis A. Stimson B.A. M.D. ______ New York
1895 Albert Yandee Veer Ph.D. M.D. - _ _ _ _ Albany
1895 Charles R. Skinner M.A. LL.D.
Superintendent of Public Instruction, ex-ofScio
1897 Chester S. Lord M.A. LL.D. ______ Brooklyn
1897 Timothy L. Woodruff M.A.. Lieutenant-Governor, ex-officio 1899 Theodore Roosevelt B.A. LL.D. Governor, ex-officio
1899 John T. MoDonough LL.B. LL.D. Secretary of State, ex-officio
1900 Thomas A. Hendrick M.A. LL.D. _____ Rochester
SECRETARY
Elected by regents
1900 James Russell Parsons je M.A.
DIRECTORS OF DEPARTMENTS
1888 Melvil Dewey M.A. State library amd Home education 1890 James Russell Parsons je M.A.
Administrative, College and High school dejp'ts 1890 Feedeeiok J. H. Merrill Ph.D. State museum
CONTENTS
Prefatory note 5
Introduction .......... 6
Chapter 1
Stratigraphic structure of Becraft mountain .... 6 Chapter 2
Description of the fauna 16
Vertical range of species . 65
Faunal values of species 68
Chapter 3
Nature and distribution of the Oriskany fauna in New York 72
Distribution of the calcareous facies 72
Ulster county , 72
Orange county ......... 75
Albany and Schoharie counties 77
The original Oriskany sandstone 78
Fauna of the Gaspe limestones ...... 80
Chapter 4
The Devonic age of the Helderbergian fauna and the base
of the Devonic system in New York .... 82
1 the argument from correlation ..... 83
2 the argument from the intrinsic character of the fauna 83
3 the argument from stratigraphy ^95
Fauna of the Manlius limestone . . ... * 98
Explanation of plates 103
Index ,122
I
PREFATORY NOTE ^
The original purpose of this work was solely to depict the character i
and composition of the Oriskany fauna of Becraft mountain, which of j
itself displays many features of interest. In its progress, however, vari- \
ous questions have arisen which concern the intrinsic value of the fauna i! and its importance in correlation. Yet without an understanding of the
fauna itself it would be impracticable to discuss the latter problems, and ' for this reason the title of the paper is restricted to the principal argu-
ment of the work, to which the discussions of somewhat broader scope 1 are corollaries.
THE ORISKANY FAUNA OF BECRAFT MOUNTAIN, COLUMBIA COUNTY, NEW YORK
INTRODUCTION
The existence of a fauna in the New York series linking together in the character of its species that of the calcareous shales and lime- stones of the Lower Helderberg and that which has been regarded as pertaining to the normal Oriskany sandstone of Oneida county and westward sections, was first brought to public notice in 1892, in a paper published by Prof. Charles E. Beecher and accompanied by a list of the species prepared by the writer.'
The interesting bearings of this assemblage of species, its new forms and new associations and its real importance in the correlation of the lower Devonian are sufficient reason for presenting its char- acteristics in detail.
The fauna in its highest development is found at Becraft moun- tain, about 2 miles east of the Hudson river, near the city of Hud- son in Columbia county. Strata of the same horizon occur at other localities in the state and carry some of the characteristic species which appear in profusion on Becraft mountain. Such outcrops are found in Ulster and Orange counties on the west side of the Hudson, but they quickly disappear in the westward extension of the Oriskany formation.
Chapter 1
STRATIGRAPHIC STRUCTURE OF BECRAFT MOUNTAIN
Becraft mountain has been the subject of geologic observation since the early report of W. W. Mather on the geology of the first district of New York (1842). A brief account of the succession and structure of the rock beds will be found on page 351 of that work, and a very
' Notice of a new Lower Oriskany fauna in Columbia county, N. Y. by C. E. Beecher, with an Annotated list of fossils, by J. M. Clarke. Amer. jour. sci. 1892- 44:410-14.
ORISKANT FAUNA OF BECBAFT MOUNTAUT 7
generalized section across the mountain from east to west is given on plate 24, iigure 6. The mountain is an outlier of principally early Devonic strata about 2 miles in north and south extent, and these rest unconformably, as shown by Mather, J. D. Dana and W. M. Davis, on the upturned slates of the Hudson river formation. The most com- plete and interesting portrayal of the structure of this area is that given by Davis.'
Accompanying that paper is a sketcli map of the mountain giving the stratigraphic succession both in plane and in section. It is not my purpose to enter into great detail with reference to the structure of this area, but, to point' certain . of my observations, I have taken the liberty to represent on a somewhat different scale, the map given by Prof. Davis, with some emendations of the contacts of the various formations and the addition of two important divisions not noted by him.
Over the northern portion the mountain is a simple, low syncline; and toward the central part it shows a double syncline separated by a very short fold, at which the layers of the Becraft limestone come to the surface. Again, farther south the duplicate form of this syncline is in a measure lost and the structure gradually becomes more compli- cated, particularly at the southeast edge of the area. This was indi- cated by Mather, who in one of his sections suggested that the rocks at this point were overturned. Davis likewise left the structure here in some doubt. The first strata resting on the upturned Hudson river slates,* are those of the Tentaculite (Manlius') limestone, which nearly inclose the entire area and on the northeast and southwest boun-
'Amer. jour. sci. 1883. 3d ser. 26:381-89.
"At Mount Moreno, just south of the city of Hudson, these slates carry a fauna with Coenograptus gracilis, Didymograptus Sagittarius, D. tenuis Hall and other graptolites identical with those of the Normanskill shales at Kenwood and Glenmont, Albany county. The taxonomy of the great mass of so-called Hudson river slates in the Albany region which has recently been studied bj Ruedemann points to the early Trenton age of the Normanskill shales and inferentialiy of these slates lying beneath the Manlius limestone of Becraft mountain. ^See footnote, p. 8
8
KEW TOKK STAT£ MtTSEUM
daries are rendered very conspicuous by their strong escarpment. Over this lies the Pentamerus (Coeymans*) limestone, characteristically devel- oped, and thereon a well defined mass of Catskill shaly (New Scot- land') limestone. The latter is overlaid by the Becraft' limestone. To these four formations Davis assigned the following thicknesses:
Manlius limestone 20-30 feet
Coeymans limestone 40-50 feet
New Scotland beds 50-60 feet
Becraft limestone 40-50 feet
^The requirements of uniformity in stratigraphic nomenclature are compelling the relinquishment of 6uch of the early division names in the New York series as do not indicate localities of exposure. In order to save to the state of New York its preeminent title to the names of these divisions and in the farther hope of per^ petnating an equable grouping of the stratigraphic units of the New York series, the writer, in conjunction with Charles Schuchert, has recently {Science. Dec. 8, 1899, American gedogiM. Feb. 1900) proposed the arrangement of the formations given in the following table. This proposition has been carefully considered and is the result of mature deliberation.
ITEW YOEK SERIES
BBA OK STSTXH
PE&IOD OR GEOUP
AOK OR STAGE
Cambric
or Taconie
Champlainic*
(Lower Silurian and Ordovician)
Georgian
Acadian
Potsdamian
' Canadian** (Paleochamplainic)
Mohawkian* (Mesochamplainic)
Cincinnatian'* (Neochamplainic)
Georgia slates
Potsdam sandstone and limestone
f Beekmantown limestone*' I Chazy limestone
f Lowville limestone** i Black river limestone [ Trenton limestone
f Utica shale
< Lorraine beds*'
[ Richmond beds (Ohio and Indiana)
0R18KANY FAUNA OF BECEAFT MOUNTAIN NBw YOKK SEUIE8 coutimied
SKA OB STsnu
Ontaric*
or Siluric
Devonic
muoD OE owavT
tat OB tftkom
|
Oswegan* (Paleontaric) |
|
|
Niagaran' (Mesontaric) |
|
|
Cayugan* (Neontaric) |
|
|
.2 |
Ileldcrbergian |
|
Orifikanian*" |
|
|
Mesodevonic |
Dlsterian** Erian'» |
Senecan '
Chaiitauqaan**
\ Oneida conglomerate i Shawangunk grit
[ Medina sandstone
f Clinton beds I Rochester shale 1 Lockport limestone [ Guelph dolomite
[ Salina beds
< Kondout waterlime"
[ Manlius limestone'*
Coejmans limestone"' New Scotland beds"* Becraft limestone"" Kingston beds"^
Oriskany beds
IEsopns grit"* Schobarie grit Onondaga limestone
I Marcellus shale 1 Hamilton beds
f Tully limestone
Genesee shale
Portage beds
(Naples beds, Ithaca beds, Oneonta beds,
local facies)
f Chemung beds
(Catskill
sandstone"' local facies)
1 Champlainic. This most appropriate designation was introduced by the concur- rence of the four geologists for the formations here assigned to it (excluaive of the Potsdam sandstone), and it has clear right of way over the later application of the name to the period of postglacial alluvium. That the later term has become ingrained in
10 NEW YORK STATE MUSEUM
literature renders it all the more conspicuous as an infraction of the law and of the rights of the men who first proposed it. In the face of Champlain, 1842, the term Ordovician has no standing.
2 Ontaric. Vanuxem placed the base of the Ontario division at the "gray sandstone," Hall and Emmons at the Medina, Mather at the Shawangunk grit. Vanuxem and Hall terminated the above division with the Niagara, Emmons included the Salina and waterlime. Growing evidence fully indorses Emmons's view as to the termiuation of the group and period with the clearing of the Salina sea.
3 Canadian. This term has the prestige of time and priority.
4 Mohawkian (new). Conrad and Vanuxem made use of tlie term, Mohawk limestone, for certain of the calcareous layers beneath the Trenton, bnt they differed so widely in their application of the term that in the summation of their results, the geologists decided to abandon it. The name is here revived with a broader mean- ing. The valley and watersheds of the Mohawk river afford typical exposures of all members of the group.
5 Cincinnatian. The formations of the Neochamplainic are not as completely developed in the state of New York as in Ohio and Indiana. In the latter sections the Lorraine fauna is represented, but is followed above by the well defined fauna of the Richmond beds. Probably in no other region is the succession of these faunas so complete as about Cincinnati, and this fact justifies the recognition of the term Cincinnatian, which already has historic value. For a full description of the series by Winchell and tJlrich, see Oeol. and nat. hist. sur. of Minn. 1897. v. 3, pt 2, p. 101-5.
6 Oswegan. This name is appropriate on account of the widespread occurrence of the Oneida and Medina formations in Oswego county, N. Y. Vanuxem employed the term, Oswego sandstone, for the formation subsequently and by common consent called Medina sandstone. In reviving the name, though with a broader meaning than in its original use, it derives its title from its early date.
7 Niagaran. In the sense suggested by Prof. Dana.
8 Cayugan (new). The divisions of this group are knit together by lithologic and faunal characters and are distinctly Ontaric. The outcrops are typically exposed about the north end of Cayuga lake, N. Y.
9 Helderbergian. The present state of our knowledge does not permit the use of the term, Helderberg, in its original scope. The Helderberg division was made to embrace formations now regarded as constituting the lower and part of the middle Devonic. We propose to restrict the term Helderbergian to the forma- tions currently known as Lower Helderberg, excluding the Tentaculite limestone.
ORISKANY FAUNA OF BECBAFT MOUNTAIN 11
10 Oriskanian. The Oriskany formation varies considerably in the chaiacter of its sediment. Its calcareous fades is highly developed in eastern New York, while the more silicious sediment excludes all others in the central part of the state. The fauna of the Oriskany from its lowest beds, as at Camden Tenn., to its highest beds, as in the province of Ontario, shows progress in differentiation, but it is not yet practicable to subdivide the New York development of the fauna.
11 Ulsterian (new). From the outcrops of all the members in Ulster county, N. Y.
12 Erian. The Erie division comprised the formations from the top of the Onondaga limestone to the top of the Chemung. We propose to save the term to the New York nomenclature by reviving it with a restricted meaning.
13 Senecan (new). In Seneaa county and along the shores of Seneca lake are excellent exposures of these beds.
14 Chautauquan (new). From exposures in Chautauqua county, N. T.
15 Beekmantown limestone (new). The Calciferous sandrock of Eaton and authors generally. This formation took its original name from sections in the Mohawk valley, where the rocks are without fossils. At Beekmantown N. Y., the normal fauna is finely developed and the rock section essentially complete.
16 Lowville limestone (new); instead of Birdseye limestone of common use. Lowville is a town in Lewis county, N. Y., where these beds are well exposed.
17 Hudson river beds. It is becoming increasingly evident that the great mass of shale in the Mohawk and Hudson river valleys which was designated at an early date by this term is resolvable into horizons extending from the middle Trenton to and including the Lorraine beds. At present it seems unlikely that, when this determination of horizons has been carried through the series, any part will remain to which the original term can be applied by virtue of its distinctive fauna, though it may still serve to designate a facies of the formations mentioned.
18 Rondout waterlime (new). From the fine development of these beds in the extensive cement quarries at and near Rondout N. Y.
ly Manlius limestone. Tentaculite limestone of Gebhard, Mather and later writers. The name here used was introduced by Vanuxem and is entitled to first consideration. Manlius is the place of typical exposure in Onondaga county, N. Y.
20 Coeymans limestone (new); and
21 New Scotland beds (new). These terms designate respectively the Lower Pentamerus (Heiderberg and Pentamerus limestones of the New York geologists) and the Catskiil or Delthyris shaly limestones. Coeymans and New Scotland are adjacent towns in Albany county, N. Y., through which runs the Heiderberg escarpment, affording the finest exposures of these formations.
12 NEW YORK STATE MUSEUM
The Becraft limestone, a heavy bedded rock, hard, gray and sub- crystalline, occupies the position of the Scutella limestone as developed in the Helderberg and Schoharie sections and pi>obably represents both the Scutella and Upper Pentamerus limestones of those sections. Over the summit of the Becraft limestone on the eastern ridge of the moun tain the surface slopes gradually downward to the west and follows the dip of the strata.
At the base of this slope is a marshy area draining toward the south, and in the vicinity of this low region and ' above it for about one third the width of the slope is the outcrop of the Oriskany which was not recognized by Prof. Davis. This is largely concealed under the soil, and there are no very clearly defined exposures of it except where the soil has been removed from small areas, in which case the surfaces rather than the edges of the strata are seen; but a considerable quantity of the rock that has become loose has worked up through the soil, and is not only found near its proper site but is scattered abundantly through the stone walls in the immediate vicinity of the strata themselves, so that the material is to be looked for and found most abundantly on the westward slope of this syncline and in the vicinity of the little stream thi'oughout its extent. These strata, highly silicious, hard, dark limestones, have been most favorably exposed to decomposition, and in consequence the calcareous matter has
22 Becraft limestone. This name was introduced by N. H. Darton with the sanction of Prof. James Hall, for the beds previously known as the Upper Pentamerus and Scutella limestones of the Helderberg sections. The present name is derived from Becraft mountain, Columbia county, N. Y.
23 Kingston beds (new). The " upper shaly beds " of W. M. Davis, which are typically exposed and attain a thickness of 250 feet in the vicinity of Kingston N. Y.
24 Esopus grit. Proposed by Darton with the approval of Prof. Hall, for the old term Cauda-galli grit. It has been suggested by Freeh that the Esopus grit should be regarded as a part of the arenaceous sediments of the Oriskany. The very few fossils which it contains, however, do not as yet fully indorse this suggestion.
25 Catskill sandstone. This is an approximate expression of the value of this formation. Catskill sedimentation doubtless began as early as Portage time, its representation during which is expressed in the term, Oneonta beds.
Geological Map
OF THE
Becraft Mountain Synclinal
Manlius Coeymans NewScotland Becraft Kin§;.ton On'skany (Tenraculite) (Pentamerus) (Shaly) (Upper Shaly)
ym ^
Esopus Schoharie Onondaga
The Hudson River Slates onthe Outskirts of this Area are not Represented
SCALE.
1 incK^^llodk
ORISKANY FAUNA OF BECEAFT MOUNTAIN 13
been largely leached out for a considerable depth on all exposed sur- faces, only a porous residuum remaining. This light, rusty and firm rotten stone retains the external and internal casts of the fossil remains with which it is filled, in exquisite detail and forms excellent material for study. Only by hastening nature's process with acid can the fossils be made out from the black and cherty or unchanged calcareous cores of this rock.
It is not easy to estimate the actual thickness of these strata at this place, as it would appear that they have been partly eroded, but there is no evidence above them of the black chert beds which ter- minate the Oiiskany deposits in the Ulster, Albany and Schoharie county sections, nor of the characteristic white quartz sandstone of the central sections. These beds rest on an argillaceous limestone, which seems to be present in only slight force and is almost wholly if not quite concealed; the "upper shaly" or Kingston limestone, blocks of which are frequently found in close association with the Oriskany and so closely resemble the latter that considerable care and experience are requisite to avoid confounding the two. The author has therefore taken utmost care in making up the list of species of the Oriskanj^ to eliminate all this "upper shaly" material from consideration. This is readily done after experience in recognizing the lithologic differences, aided by the fact that the Kingston limestone contains but very slight intermixture of Oriskany species. The Helderbergian species here regis- tered, therefore, occur in Oriskany limestone and in immediate association with Oriskany fossils.
From the axis of the syncline, specially along the north and south road crossing the mountain, is a ridge of gray, sandy grit with slaty cleavage so strongly developed that the original bedding is entirely lost. This rock covers a large area from the center of the region and constitutes the high ridges which cap both of the synclinals. Prof. Davis regarded all of this rock, which in places rises in very sharp escarpments, par- ticularly on the east of the southern part of the road mentioned, as the Cauda-galli giit (Esopus slate). I have found however in various places, specially near the junction of the middle road with a crossroad from the west starting in at the glue factory, that this rock contains
14 NEW YOUK STATE MUSEUM.
fossils wedged in between the cleavage planes and lying with their surfaces parallel to the true bedding. These are exceedingly diffi- cult to extract, but among them it has been possible to identify Dalmanites anchiops; Phacops, a fragment of a head without spine on the genal angle, (cf. P. bombifrons); Coelospira (cf. Camilla); Chonetes, large (cf. arc u at a). These fossils are suffi- cient to show the presence here of the Schoharie grit. They have not been fotind throughout the entire thickness of this formation, and are under all circumstances very rare, but, while we may safely ascribe a portion of the formation to the Esopus slate, it is necessary to regard at least that portion represented as such on the accompanying map as belonging to the Schoharie grit. It is observable that, where these rocks contain fossils, some calcareous matter is present.
The existence of the Corniferous limestone, the highest and. latest of all the formations, was also determined by Prof. Davis ; and to this he ascribed a thickness of 10 to 15 feet, but he speaks of having found no fossils in it and is somewhat uncertain as to the correctness of his reference to the limestone of this formation. This rock is a chert-bearing, light colored, almost white limestone, the chert lying in layers and the entire thickness of the mass being from 15 to 20 feet. In stratification it is essentially horizontal, or with a very slight dip east. There can be no question that it is the Onondaga limestone. The layers are sparsely fossiliferous, showing traces of rugose corals, particu- larly Zaphrentis and well defined examples of the brachiopod Spirifer raricosta. Directly beneath the outcrop of these beds are seen beds with- out flint which are calcareous and shaly or shaly with calcareous lenses, the limestone itself being blue and the shale weathering brown or rusty gray. These beds show conclusive evidence of false bedding, as a vertical slaty cleavage is highly developed, and in this respect they resemble those seen near the roads below, which we have already referred to the Schoharie grit. They thus appear to lie at a high angle beneath the chert-bearing beds, but are unquestionably conformable to them, as is shown by the nearly horizontal position of the fossils they contain. Nevertheless, these fossils, which are so wedged into the rock that it is difficult to release them, are variously distorted by pressure and only very compact bodies like solid corals have escaped such distortion. The following species have been determined from these layers.
OEISKANY FAUNA OF BECBAFT MOUNTArtT 15
Odontocephalus selenurus; Spirifer varicosus; Atrypa reticularis, large and rotund; Leptaena rhoraboidalis ; Strep, torhynchus pandora; Chonopliyllura; Zaphrentis; Favo- sites, branching; Stroma topor a or Fistulipora, incrusting. With the evidence before us then, we have no hesitation in concluding that the succession of the upper Helderberg beds from the top of the Oriskany sandstone upward is fairly complete, representing the Esopus slate, the Schoharie grit, the non-chert-bearing Onondaga limestone and characteristic " Corniferous " limestone.
Chapter 2
DESCEIPTION OF TPIE FAUNA
TRILOBITES
Dalmanites (Synphoria) stemmatus sp. nov,
Plate 1, flg. 6-16 ; plate 3, Sg. 1, 3
1892. Dalma/nitea, sp. nov. A, Clarke, op. cit. p. 412
Species attaining considerable size. Cephalon convex, abruptly slop- ing to the genal margins. Genal extremities somewhat produced but rela- tively short and terminating in broad, obtuse angles. Dorsal furrow deep except at the junction of the glabellar lobes with the palpebral lobe, where it becomes shallow and very much elevated. Frontal lobe of glabella large, rounded in front, slightly elongated at the axial extremity but not projecting beyond the frontal border or facial suture. First lateral furrows long, deep and oblique, extending nearly three fourths the diameter of the lobe. Glabellar surface behind the frontal lobe slightly if at all depressed medially. Second and third lobes wholly confluent at their extremities, often but a remnant of the second lateral furrows remaining. Together these coalesced lobes have a sub- triangular or subclavate outline and are convex and elevated at their distal extremities, rising above the full hight of the glabella and almost to the hight of the palpebral lobe. The third lobes are small and narrow,
16 NEW rOKK STATE MUSEUM
making an annular segment, varying but little in widtii; their extremi- ties are almost concealed beneath the projecting lobes in front. Occi- pital furrow deep; occipital segment long and very much arched; no central spine or tubercle. Cheeks with steep lateral slopes; somewhat concave within the thickened margin. Furrows beneath the eyes deep, narrow, with elevated margin having a vertical, outward slope. Occi- pital furrow widening from the dorsal furrows outward and coming to a rather abrupt termination without meeting the submarginal depression of the cheek or extending on the genal expansion. Eyes large, ele- vated, the palpebrum higher than the palpebral lobe.
The thickened border bears a row of crenulations or crescentic orna- mental processes, which are the most extended at the anterior extrem- ity; here also the anterior three of these processes are somewhat coal- esced. From this extremity may be counted, on both sides of the ter- minal process, from 12 to 15 similar processes, becoming uniformly smaller toward the genal extremities and finally disappearing altogether at or near the lateral termination of the facial suture. In small speci- mens the number of these processes may be considerably less.
The surface of the cephalon is ornamented, on the frontal lobe of the glabella, with coarse pustules of varying size ; this lobe also bears the elongate median scar which occurs in many species of the genus. The coalesced second and third lobes are also pustulose but less strongly. The cheeks directly beneath the eyes bear traces of low ramifying grooves similar to those found in Dal. pleuroptyx of the Helder- bergian fauna and Dal. anchiops of the Schoharie grit.
Thorax not observed.
Pygidium very broadly triangular, the length and width being as 2 to 3. The margin curves slightly outward on each side and terminates behind in a broad, rounded extremity which is slightly elongated but is not produced into a spine. The axis bears 10 or 11 annulations, and the pleurae 9 or 10. The ribs are undivided by a median groove and are without coarse tubercles.
Observations. This interesting species shows its immediate affinities in many of its structural features. The peculiar ornamentation of the
\
OEISKANY FAUNA OF BECEAFT MOUNTAIN 17
frontal margin of the cephalon is possessed in less degree and different quality by several antecedent species. Thus as far back as the Dal. vigilans Hall, and Dal. verrucosus Hall of the later Niagara (Waldron) fauna there is a pronounced development of a short and simple spatulate process at the anterior extremity. In the Dal. pleuroptyx Conrad, of the Helderbergian, this process becomes broadened and divided, the divisions taking on the character of those in Dal. stemmatus, though being less numerous and of less extent along the border. In Dal. anchiops Green, of the Schoharie grit, a similar character is manifested,' extending for a short distance on either side of the extremity. Dalmanites (Odontocephalus) selenurus Eaton, of the Onondaga limestone, has the frontal margin developed by perforation into incisor-like processes, which again extend but a short distance from the extremity, v^^hile in Dal (Corycephalus) regalis Hall, of the Schoharie grit, the processes are blunt, distant and extend to the ends of the cheek spines. In the limestone beds at Port Jervis, the " trilo- bite beds " of Barrett, are the species Dal. dentatus Barrett and Dal. dolphi Clarke, the former with a row of pointed triangular pro- cesses extending nearly to the extremities of the cheek spines, the latter with a stronger compound anterior process and two or three sharp lateral processes on each side. Thus the marginal ornamentation of the head is seen to be subject to much variation, and from the simple anterior extension of the frontal border manifested in some of the late Siluric species, through the Dal. pleuroptyx of the early Devonic into Dal. stemmatus of the • Oriskany, there has been a simple intensi- fication and extension of the type of crenulate ornament. Here, however, the line ends, to be re])laced and followed by the various phases above mentioned.
As to the employment of the term Synphoria, which is used in the title of this species, a few remarks may be made. To some of the ornamental expressions of Dalmanites referred to, generic or subgeneric terms have been applied, e. g., Odontocephalus for Dal. selenurus, Corycephalus for Dal. regalis, etc. It
^See Paleontology of New York. v. 7, pi. 10, fig. 11.
18 NEW YORK STATE MUSEUM
seems of very doubtful propriety to attempt to carry out such dis- tinctions in this genus, and it is proper to make this remark here lest the outstanding ornamental variations not yet included under such sub- divisions offer a temptation for the erection of parallel divisions. A much more fundamental character is found to exist in many of these Devonic Dalmanites, viz, the coalescence of adjacent members of the first and second pair of glabellar lobes. This is a difference of rexl significance in the anatomy of the animal, and it distinguishes a considerable number of forms from the normal Dalmanites in which the division of the lobes named is complete.
In the species of the early Siluric such coalescence is obscurely manifested, as in Dal. (Pterygometopus) eboraceus Clarke and Dal. (Ptery.) intermedins Walcott, but here in association with other characters which have been found a basis for a subgeneric distinction. The upper Siluric was a period of full, typical development of Dal- manites, and we observe that the Helderbergian species of the genus maintain their typical character in this respect. Dalmanites stem, m a t u s is the earliest Devonic form in which coalesence is pronounced. Then follow Dal. anchiops Green and var. sobrinus il. and C, Dal. regalis Hall, of the Schoharie grit, Dal. selenurus Eaton, Dal. macrops Hall, Dal. diurus Green, Dal. calypso Hall and Dal. myrmecophorus Green of the Onondaga lime- stone. Within this group of species we find much diversity of mar- ginal cephalic ornament : in Dal. macrops, Dal. calypso and Dal. diurus the frontal border is undivided ; in Dal. anchiops it is moderately crenulated ; in Dal. selenurus it is divided into incisor-like processes (Odontocephalus); in Dal. regal is the processes are different and extend over the entire margin (Corycepha- lus); in Dal, myrmecophorus the cephalic margin is not known, but the pygidial margin is highly modified (Coronura).
Turning to the Devonic species of this genus which possess the typical separation of the first and second lobes, we may enumerate Dal. pleuroptyx Conrad, Dal. dentatus Barrett, Dal. d o 1 p h i Clarke, of the Helderbergian, Dal. boothi and var. calliteles Green, of the Hamilton shales ; the first three bearing
ORISKANY FAUNA OF BECK AFT MOUNTATN 19
cephalic ornament and the others with none, but possessing highly char- acteristic pygidia (Cryphaeus). It seems therefore very probable that the term Synphoria, introduced by the writer some years ago, in its application to the former group of species having coalescent glabellar lobes, may prove of subgeneric significance in distinguishing such forms from the typical Dalmanites.
Dalmanites (Synphoria) stemmatus, var. convergens var. nov.
Plate 2, flg. 8-5
1892. Dalmanites sp. nov. A. var, Clarke, op. cit. p. 412 Not infrequent in this fauna are small pygidia of Dalmanites having the same degree of annulation as Dal. stemmatus but with a more slender and tapering outline. At the posterior extremity, also, there is a short but acute termination. A few cranidia of correspond- ing size show a slight crenulation of the anterior margin.
Dalmanites phacoptyx Hall and Clarke
Plato 2, flg. 10
1888. Dalmanites phacoptyx ^aM und Chrke, Paleontology of I^ew York. 1:51, pi. 9a, fig. 23-27
This species was founded on some large but incomplete pygidia from the Upper Helderberg (Ulsterian) at North Cayuga, Ontario, which are characterized by their narrow, divided pleural ribs, long, cylindric tail spine and irregularly tubercled surface, some of the tubercles being large and having the form of spinules. These spinules occur without arrangement on the pleural ribs and on some of the segments of the axis. Lesser tubercles are scattered over the surface and are crowded on the sides of the axis.
A few specimens representing this species have been found in the Oriskany.
Dalmanites bisignatus sp. nov.
Plate 2, flg. 6-8
1892. Dalmanites sp. nov. B, Clarke, op. cit. p. 412 Cephalon and thorax not known.
Pygidium elongate triangular, sloping to a sharp angle which may be extended into a short, flat spine. Axis quite slender and with
20 NEW YORK STATE MUSEUM
slightly incurving dorsal furrows. Segments transverse and narrow, 12 to 14 in number on internal casts, bearing a double median row of strong and sharp tubercles with fine and faint pustules at the side. Pleurae with 12 ribs which are separated by broad, flat grooves ; these ribs are narrow, flattened above and divided by a fine median, linear sul- cus. Very small tubercles are scattered irregularly over the ribs.
These are pygidia quite closely similar to that of Dal. d e n t a- t u s Barrett, of the Port Jervis limestone and the Dal. p 1 e u r o p- t y X Conrad, of the Helderbergian. The differences are these : in Dal. dentatus the ribs of the pleurae are fewer in number^ more deeply divided by the sulci and more strongly pustulose ; on the axis the median row of tubercles consists of two, three or four with lesser ones at the sides. In Dal. pleuroptyx the number of axial and pleural segments is generally more than here, the oiitline of the shield is less sharply triangular and, while the pleural ribs are of much the same character, the ornamentation of the surface is different, consisting of a fine granulation extending over all annulations with but a slight tendency to become coarser on the axis.
Phacops correlator sp. nov.
Plate 2, fig. 9
1892. Phacops {Acaste) of. anceps Clarke, op. cit. p. 412
This very interesting fossil I was at one time disposed to regard as identical with Phacops anceps of the Upper Helderberg lime- stone. On comparison with the original specimen, which was described and figured by the writer in volume 9, Archivos do miiseu nacional do Rio de Janeiro. 1890. p. 16, pi. 1, fig. 3, a difference appears, which will not permit the union of the forms, and this is found in the sharper development of the glabellar furrows. In Ph. anceps, the only known example of which is an internal cast of the cephalon in limestone, there is no trace of the first and second pairs of these furrows, but in Ph. correlator these furrows are quite clearly developed both on internal casts and impressions of the exterior. There is still a degree of uncertainty whether all these specimens may not prove to belong
ORISKANY FAUNA OF BECRAFT MOUNTAIN 21
to the same species ; for in Ph. braziliensis, of the Maecuru Lower Devonic, another species very closely similar to Ph. anceps, the glabellar farrows may be all well displayed on the internal cast.'
The three species above mentioned are alike in the small size of the cephalon, having the same dimensions in all specimens observed, in the rounded genal angles, the firmness of the union of cranidium and cheeks, separated specimens being very unusual, the peculiar dalmanitiform aspect of the glabella and its slight median angulation, the small eyes and smooth surface. Though the other parts of the species are not known, yet the cephalon indicates the intermediate nature of these species between the genera P h a c o p s and D a 1 m a n i t e s, and doubt- less when the rest of the body has been found, it will express similar relations.
The existence of expressions of this type of structure in the Lower Devonic of the Amazons (Maecuru), of Cayuga, Ontario, at Becraft mountain and nowhere else, so far as known, is a fact of significance in the correlation of these faunas.^
Phacops logani Hall
Plate 1, flg. 1-5
1892. Phacops sj>. nov. Clarke, op. cit. p. 412
In the notice above cited I suggested the similarity of the speci- mens of Phacops here found to Phacops logani of the Hel- derbergian and Ph. p i p a of the Onondaga limestone. Restudy of the material has convinced me that the fossil is not to be distinguished from the former. Though the species is of frequent occurrence, the specimens are generally somewhat distorted cephala and pygidia, and few entire examples have been observed. Such distortion generally gives a too pointed, subpentagonal fomi to the glabella and a too narrow and elongate form to the pygidium. The characteristic traits of the species Ph. logani are these : the glabella is relatively narrow and strongly
^See Archivos do mupeu nacional do Rio de Janeiro, v. 9, pi. 1, fig. 1, 2. ^The writer has recently obtained specimens representing the same type of structure in the Gasp^ sandstone at Gaspe Basin Quebec.
22 KEW YOEK STATE MUSEUM
projacent at the front; its surface shows without compression both the oblique and transverse moieties of the first glabellar furrows and also the second furrows; the occipital ring is strongly arched and bears a conspicuous tubercle. On the axis of the thorax just within the dor- sal furrows is a row of large tubercles, one at each end of every axial segment. These are not ornamental, but are more strongly marked on the internal cast than on the external surface; they become smaller posteriorly but on the cast show themselves even on the first segment of the pygidium. The pygidium bears five or six lateral segments, flat and divided by linear furrows which are generally obscure on the cast.
While these are the diagnostic characters, the species has some other traits which it shares with but few allies. There is a small spinule at the extremity of the cheeks, such as occurs in Ph. c r i s- t a t a and Ph. p i p a of the Schoharie grit and Onondaga limestone ; no spinules or conspicuous tubercles occur on the axis, such as are found in Ph. cristata but are absent in Ph. p i p a. The divis- ion of the pleural ribs on the pygidium is a feature not displayed in the later Devonic species of the genus (e. g., Ph. ran a).
The specimens from Becraft mountain have for the most part these characters of Ph. 1 o g a n i. Examples of the thoracic segments of adult forms have proved rather uncommon, but those seen have the rows of tubercles along the dorsal furrows well developed, while in smaller forms these are less conspicuous and may be so far absent as to sug- gest the possibility of there being a second species ; and yet it is to be noted that these tubercles are less clearly developed in the later seg- ments of Ph. logani and it may be are obscure in young examples of the species.
Cordania becraftensfs sp. nov.
Plate 2, fig. 19-23
1892. Cordania, sp. nov., Clarke, op. cit. p. 412
Of this species only the cranidia and pygidia are known. The former have a subcircular, marginal curve, with a round, thickened and much elevated border which is clearly delimited within and is followed by a relatively narrow and shallow depressed area passing into the con-
ORISKAinr FAUNA OF BECEAFT MOUNTAIN 23
vexity surrounding the glabella. The latter is ovoid, convex and large extending two thirds the length of the cephalon. Its anterior extremity is rather broad and blunt, and at its base are two subtriangular or ovoid lobes set off from the glabella by deep, oblique furrows. The other glabellar furrows manifest themselves in the manner characteristic of this genus, the first pair making a broad indentation just in front of the middle, very noticeable on the internal cast, and the second pair being extremely obscure. The ornamentation of the head consists of very fine pustules vsdth larger ones scattered among them. This character is maintained over the glabella to the frontal margin, where the coarser pustules disappear, leaving the surface here with a very fine granulation, and on the doublure this is replaced in part by punctation.
Pygidium subcircular, axis very convex, incurving toward the extremity. The annulations are narrow and not direct, but rise nearly vertical from the dorsal furrows or with a slight forward inclination, then, at less than one third of their length, bend forward with a dis- tinct angulation curving anteriorly over the median line. These annula- tions are nine, and beyond the last that is well defined may be counted three more obscurely defined. The interannular grooves are narrow. The pleurae are broad, convex about the median region, becoming depressed toward the margin, sometimes defining a narrow border. The ribs are seven, rather broad, obscurely grooved for most of their length by a linear sulcus which becomes well marked on the border and gives the ribs the appearance of being bifurcated. The intervening furrows are narrow. The ornamentation consists of fine, uniform tubercles on all annulations, with a single axial row of strong, spinous tubercles directed posteriorly.
This species, in its general aspect and comparatively large dimen- sions, approaches Cord, cyclurus H. and C. of the Helderbergian much more nearly than it does any of the later species, which are uni- formly smaller and differently ornamented. In Cord, cyclurus the cephalon has a few coarse tubercles on the border, and over the concave area between the border and the glabella are fine, inosculating furrows. The distance between the border and the anterior end of the glabella is less in Cord, cyclurus than in Cord, becraftensis. In
24 NEW YORK STATE MUSEUM
the former species also the pygidium has the axial row of tubercles smaller and duplicate toward the extremity, and lacks the fine granulation of the entire surface.
The species is not iincomraon in this fauna.
Cordania hudsonica sp. nov
Plate 2, ag. 17, 18
A few pygidia show the presence of a quite distinct species of this genus. They are of small size, broad and quite short, the axis covering about one third the width of the shield, somewhat flattened and not incurved as in Cord, becraftensis and Cord, cyclurus. They bear eight or nine narrow, transverse annulations which show no angu- lations. The pleural ribs are six, with a trace of a seventh, are quite narrow, with interannular furrows of equal width. They are divided by quite deep sulci, and the surface carries a few scattered tubercles.
Cyphaspis minuscula Hall (sp.)
Plate 2, flg. 21, 25
1888. Cyphaspis minuscula Hall and Clarke, Paleontology of New York. 7 : 140,
pi. 20, fig. 17; 24, fig. 7-12 1892. Cyphaspis sp. nov., Clarke, op. cit. p. 412
Cranidia of this species, distinguished from the closely allied Cyph- aspis coelebs H. and C. of the Helderbergian by the low median angulation of the glabella, are not of infrequent occurrence. Pygidia referable to the species have also been observed.
Cyphaspis minuscula is quite widely distributed in the Onondaga limestone of New York, and our present knowledge leads to the belief that it may not be easy to fix on a genuine specific difference between it and the Helderbergian form. The latter is exceedingly rare, and but two very imsatisfactory specimens have been seen. The feature above cited is the only one which could now be indicated as distinctive. Both however are sufiiciently unlike the other Devonic species of the genus, and represent a type characterized by the absence of any peculiar arrangement of tubercles, spines or punctae on the surface, the exterior being smooth or very finely granular.
OKISKANY FAUNA OF BECKAFT MOUNTAIN 25
Proetus conradi Hall
Plate 2, flg. 11-16
1S61. Proetus conradi Hall, Descriptions new species of fossils, p. 69 1892. Proetus sp. nov. ? A ; Proetus, sp. nov. B, Clarke, op. cit. p. 412
Separated cranidia and pygidia of a species of tliis genus are suffi- ciently common and these vary greatly in size. Though some of them attain much greater dimensions than any specimens of Proetus conradi, yet they all seem to agree in structure among themselves and with typical examples of that species from the Schoharie grit. Specific distinctions among such Devonic forms of this genus as express the old division G e r a s t o s, and are represented in the New York series by P. angustifrons, conradi, clarus and r o w i, are pretty close and yet dependable. The special traits of P r o e t us con- radi are its subovoid or subtriangular and quite convex glabella, tan- gent at its extremity to the inner margin of a flat frontal border, and a pygidium with sloping pleurae bearing three or four rather indistinct duplicate ribs, the axis having from 8 to 10 annulations which curve backward along the median line.
But a single entire example of the species has been observed and this is of medium size, attaining the proportions usual to species of this type throughout the early Devonic faunas.
Acidaspis tuberculata Conrad
Plate 2, flg. 26
1840. Acidaspis tuberculata Conrad, Ann. repH geol. sur. N. Y. p. 205
This species, common in certain layers of the New Scotland beds, is here represented by specimens of various sizes, often attaining con- siderable dimensions.
Lichas cf. pustulosus Hall
1859. Lichas pustulosus Hall, Paleontology of New YorTc. 3 : 366
There have been found a few fragments of pygidia and other parts of the test which may prove to belong to this Helderbergian species.
28 NEW YOEK STATE MUSEUM
Homalonotus sp?
We have previously recorded the presence of this genus as repre- sented by a few patches and fragments of the test. Their specific characters can not be made out. The genus, however, is to be expected from the fauna, as it is represented by a species of commanding pro- portions, H. major Whitfield, from the same horizon, near Marbletown, Ulster county.
CIBRIPEDS
Plumulites sp. A single plate shows the presence in the fauna of this genus of cirriped crustaceans.
ANNELIDS Conodonts Annelid teeth of this character have been observed but not in suitable condition for identification.
Autodetus beecheri Clarke
Plate 2, flg. Zl-n
1892. Autodetus sp. nov., Clarke, op. cit. p. 411
1894. Autodetus beecheri Clarke, Amer. geol. 13 : 33 i, fig. 7-19
This species is quite abundant, and young shells showing the pri- mary revolutions of the whorls are commonly found attached to the surfaces of brachiopods and spreading bryozoa. There is some varia- tion in the aspect of the body at maturity, and though the form is generally a truncated obcone, sometimes there is little difference in the diameter of the basal cicatrix and that of the final whorl. Generally, too, the surface, rough and wrinkled, - conceals all trace of the sutures, but at times these are clearly shown by the annulated exterior of the shell.
Spirorbis assimilis, sp. nov.
Plate 2, fig. 33-34
1892. Spirorbis sp. Clarke, op. cit. p. 411
Tube small, regularly coiled, not free on final whorl, all coils attached and by their sinistral surface. Inner whorls nearly concealed; number
ORISKANY FAUNA OF BECRAFT MOUNTAIN 27
of exposed whorls 2-3. Exterior of outer wborl with a low, revolving lateral carina, which gives the upper surface a flattened aspect; other- wise the surface is smooth.
This species is distinguished from young forms of Autodetus beecheri, in which the Spirorbis condition is completely inclosed in the later growth of the shell, by the much less depth of its whorls and the greater transverse diameter of the shell.
Cornulites cingulatus Hall
Plate 2, liK. 3»-38
1888. Cornulites cingulatus Hall, Paleontology of New YorJc. r. 5, pt 2 (= 7, suppl.) p. 20, pi. 116, fig. 29
The original of Corn, cingulatus is from the Helderbergian (New Scotland beds) of New York, but its precise locality is not recorded. It occurs occasionally in the Oriskany, where it presents a rapidly expanding tube with coarsely and rather irregularly rugose surface, the wrinkles being crossed by fine but sharp vertical striae. On the internal cast the annulations have the aspect of insheathed cones and are not unlike such casts of large Tentaculites, though of much less regu- lar arrangement.
Tentaculites elongatus Hall
Plate 3, flg. 8-ia
1859. Tentaculites elongatus Hall, Paleontology of New YorTc. 3 : 136, pi. 6,
fig. 16-21 1892. Tentaculites c£. elongatus and Tentaculites sp. nov., Clarke, op. cit. p. 413
The specimens of this species, described from the Helderbergian (New Scotland) limestone of the Schoharie section, are not infrequent throughout the Oriskany. Many of them show finely the sharp, filiform, concentric striae which cover annulations and depressions alike. Approaching the apex of the shells, the surface gradually loses its annulations but retains the concentric striae ; for some distance the apical region is quite free of any trace of annulations and where this part is found by itself it presents the aspect of a quite distinct species. The internal cast of the species was well characterized by Hall as resembling a series of truncated obcones one above the other; thus these casts are altogether unlike the exterior of the species.
28 NEW YORK STATE MUSEUM
Tentaculites ? acus, sp. nov,
Plate 3, fig. 1-7
1892. Coleolus sp. % Clarke, op. cit. p. 413
Shells having as large size as those of Tentac. elongatus but with the exterior surface smooth or with very faint, distant, broad, con- centric depressions and fine, indistinct and somewhat irregular growth striae. The internal cast is similar to that of Tentac. elongatus but has the constrictions less deep. Specimens of this species are not uncommon.
The wall of this species is thick and cellular, and a transverse section gives two or more concentric circles at any plane, showing the insheathment of the funnel-like divisions of the interior. This structure is miich more pronounced than in any species of Tentaculites observed by the writer and, though more regular than in Cornulites, may prove to be of the same nature.
PTEROPODS (?)
Conularia ,cf. desiderata Hall 1857. Conularia desiderata Hall, Paleontology of New YorTc. 3 : 480, pi. 72a fig- 4 A single fragment of medium size, bearing a clearly exposed septum, approaches this species, described from the Oriskany elsewhere in New York. Its surface characters are sufficiently preserved to demon- strate the broad sulci at the angles and the absence of median furrows on the four sides, but the detailed sculpture of the concentric lines is not clearly retained.
GASTROPODS
Bellerophon sp. ? A single specimen shows the inner whorls of a broad backed species.
Cyrtolites expansus Hall
Plate 3, flg. 20-23
1859. Cyrtolites ? expansus Hall, Paleontology of New Yorh. 3 : 479, pi. 104,
fig. 4, 5 1892. Cyrtolites expansus Clarke, op. cit. p. 413
The original figures and description of this shell from the Oriskany sandstone of New York were evidently based on internal casts, and
ORISKANY FAUNA OF BECRAFT MOUNTAIN 29
were, hence, not altogether satisfactory for identification. Specimens of this genus in the fauna under consideration are of not inconsiderable size and seem to represent but a single species, characterized : 1 by the sharp, concentric lamellae of the surface ; 2 by the broadly expanded aperture ; 3 by the well defined median ridge on the earlier parts of the shell, on which the striae have a pronounced retral bend, the ridge becoming obsolete at the margin. The specimens have the proportions and curvature of C y r. e x p a n s u s, and two of the figures cited (4a,b) show evidence of the concentric markings and the definition of the median ridge. Squeezes from casts of the exterior show a very fine radial striation between the concentric lines. The ajiertural slope beneath the coil bears a broad median sinus bounded by low, divergent ridges which modify the peristome.
The species is not uncommon.
Pleurotomaria sp. A single specimen of this genus has served as the surface of attach- ment for a large colony of Fistulipora, and before this coral began its growth the shell had become more or less covered with Spirorbis and Hederella. Thus, while its form is preserved with- out distortion and the slit-band is clearly shown, the character of its ornament can not be made out, and it is unwise to attempt a definition of the specific characters.
Diaphorostoma desmatum, sp. nov.
Plate 3, flg. 13-19
1892. Diaphorostoma sp. nov., Clarke, op. cit. p. 413
Prof. Hall embraced within the species Diaph. ventricosum a series of small shells which are associated with the large, normal form of that species, regarding them as young stages. Similar shells are found very abundantly in the Becraft mountain Oriskany, and we find from a careful examination of the best external casts obtainable that there is a difference in the two in respect to superficial characters; for, while in the large and ventricose shells the lineation consists of crowded, con- centric growth lines which become wrinkles on the last whorl and seem
30 NEW YOKK STATE MUSEUM
to be to a large degree the cause of the irregularities in contour often displayed by full-grown shells, the smaller form has these concentric growth lines more sharply defined and elevated, and these are covered by equally fine and sharp interrupted revolving striae, which together produce an effect similar to that exhibited by the common Hamilton species, D. lineatum Conrad. These revolving lines seldom cancellate the concentric erect lines, but profoundly modify their interspaces.
In general form these shells do not widely differ from the early whorls of D. ventricosum, but their abundance and uniformity of size in addition to the characters indicated seem to establish a specific difference.
Diaphorostoma ventricosum Conrad
Plate 3, flg. 25-28
1892. Diaphorostoma ventricosum Clarke, op. cit. p. 412
For other figures see Paleontology of New York. v. 3, pi. 112, fig. 1-10; 113, fig. 7, 8; 115, fig. 8
This species is the most abundant of all the gastropods and attains normal size and proportions, though usually the large ventricose body whorl has been crushed.
Strophostylus expansus Conrad
Plate 3, flg. 24
1892. Strophostylus expansus Clarke, op. cit. p. 412
For other figures see Paleontology of New York. v.'3, pi. 114, fig. 2, 3a, b
A single well defined example of this shell has been observed.
Orthonychia tortuosa Hall
1892. Platyceras ioriuosum Clarke, op. cit. p. 412
For figures see Paleontology of New York. 3:472, pi. 113, fig. 1-5
This species is not common, and no well-preserved examples have
been seen.
Platyceras cf. gebhardi Hall
Plate 3, flg. 89
Platyceras gebhardi* was described from the Oriskany of
'Paleontology of New York. 3:474, pi. 117, fig. 1-10.
ORISKANY FAUNA OF BECRAFT MOUNTAUT 31
Cumberland Md. A single specimen having similar characters has been observed in the Onskany of Becraft mountain, and this shows a slight departure from the type in the flattening of the outer surface of the body-whorl.
Platyceras nodosum Conrad
1892. Platyceras nodosum Clarke, op. cit. p. 412
For figures see Paleontology of New York. v. 3, pi. 115, fig. 1-C ; 116, fig. 1-4
This species, common in the Oriskany sandstone of Albany and Schoharie counties, is occasionally represented in the Becraft mountain fauna.
J^AMELLIBBANCHS
Pterinea sp. ?
(Cf. Megambonia lamellosa Hall, Paleontology of New York. 3 : 467, pi. 109, fig. 5,6)
Large but incomplete left valves indicate the presence of a species without radii but with a smooth surface showing only concen- tric growth lines. One of these exposes a part of the right valve, which has a depressed convex and similarly smooth surface. The out- line of these shells can not be clearly made out, but they present the proportions and to some degree the aspect of the species cited.
Pterinopecten subequilateralis Hall
Plate 4, fig. 14
1859. Avicula subequilateralis Hall, Paleontology of New York. 3 : 281, pi. 49, fig. 6
Prof. Hall described this species from a single valve from the Pent- amerus (Coeymans) limestone in Schoharie coiinty. The form is peculiar and interesting from its subsemicircular, nearly equilateral form and its smooth exterior. The original referred to was i-egarded as a left valve, but our specimens seem to demonstrate that it is the opj)osite valve. This right valve is convex with a long, straight hinge which makes the greatest diameter of the shell. The anterior and posterior wings are not distinctly set off from the body of the shell, but the former is the larger and is defined by a deeper concavity of the surface. The
32 NJJW YORK STATE MUSEUM
notable convexity of this right valve and the absence of byssal sinus beneath the anterior wing are features which suggest the subgenus Vertumnia Hall.
The surface is without any trace of radial marking, but bears fre- quent though rather obscure concentric lines of growth. The species is rare, and the left valve has not been observed.
Pterinopecten proteus, sp. nov.
Plate 4, fig. 4-8
Shell of medium or large size, subcircular in outline with anterior and posterior wings well developed. Left valve normally convex, right valve slightly convex or depressed. Hinge-line straight and making the greatest width of the shell.
Surface marked by an ornamentation quite variable in its expression. A few stout ribs depart from the beak and maintain their individuality to the margin, becoming broader and somewhat flattened as they extend outward. The intervals between these ribs are broad and in occasional instances are but rarely divided by minor ribs. As a rule, however, these interspaces carry one, rarely two secondary ribs, which are implanted and not produced by dichotomy, and these lesser ribs maintain their minor character throughout, very seldom attaining the size on the margin, of the primary ribs. The mode of inci-ease of these ribs is such that no tendency to their fasciculation is manifested. The variable size and number of the intermediary ribs, however, give each specimen an appearance in this respect unlike all others. The radii are crossed by fine, elevated lamellae, which are moderately and equally distant over the upper and median parts of the shell, but become closely crowded near the margins. These cancellate all radii. On the right valve there is notable variation in the size of the primary ribs, but no ribs which are distinctly intercalary except over the anterior slope. Concentric lines are also present, and these may become lamellae over the peripheral regions, in which case they may obscure the ribs and produce an approximately smooth surface. Specimens of both valves have been observed on which the predominance of the concentric lines almost obliterates the radii, specially on internal casts. This, however, is not
OEISKANY FAUNA OF BECEAFT MOUNTAIN 33
complete, the casts generally showing obscure nodes on the radrl where these have been crossed.
Prof. Hall describes as Avicula recticosta a single nght valve from the Oriskany sandstone of Albany county, characterized by its strong ribs, which are said to proceed in pairs from the umbo and to dichotomize; in these respects that shell is unlike those with which we are here dealing.
This is the most abundant of the lamellibranchs of this fauna. In
its general features it may be brought into comparison with several of
the Ulsterian and Hamilton species, but its specific traits are distinct
and pronounced.
Pterinopecten signatus, sp. nov.
Plate 4, fig. 3
Shell of medium size, obliquely suboval. Hinge-line straight and long, not exceeding the greatest diameter of the valves. Anterior ear strongly developed and nasute; posterior of moderate size not sharply set off from the body of the shell. On the left valve the byssal depression is strong, the surface normally convex. The ornament of this valve consists of narrow, filiform subequidistant radii, increasing by implantation, the first of the minor series generally attaining on the margin the full size of the piimary series. The interspaces are broad, free and subequal on the margins. These radii cross both wings, but are obscure on the anterior. Fine, erect concentric lines cross all radial lines; toward the edges these become crowded, lamellose and overlap each other. The right valve is depressed convex or flattened and bears radial striae, but the concentric lines are obscure or wanting except on the wings.
This rare species is readily distinguished from Pt. proteus by its fine, regular and uniform radii. It resembles the Onondaga species Pt. terminalis, but not closely. Pterinopecten bellulus of the Helderbergian is unlike it in having dichotomous and fascicu- late radii.
Pterinopecten pumilus, sp. nov.
Plate «, flg.
The sole example observed of this species is a right valve of very
34 NEW YOEK STATE MUSEUM
small size and quite considerable convexity. The beak is subcentral, the outline and contour slightly oblique and the wings not distinctly separated from the body of the valve. The surface bears from 40 to 50 fine radii, the majority of which arise by dichotomy over the median parts of the valve, but all have about the same size and are equidistant on the margin. These are crossed by extremely fine, con- centric lines and a few obscure undulations.
The convexity of this valve shows the relation of the species to those later Devonic shells which have been referred by Hall to the subgenus Vertumnia.
Aviculopecten sp.?
A small right valve of orbicular outline has deeply concave wings and a depressed surface with extremely faint and fine radii.
Lyriopecten sp. ?
An imperfectly retained right valve has very obscurely defined wings, the anterior wing not interrupting in any way the convexity of the shell. The surface is cancellated by fine radii in several series, crossed by concentric, erect lines.
Actinopteria communis Hall
Plate 4, flg. 1, 2
1859. Avicula communis Hall, Paleontology of New York. 3:286, pi. 51, fig. 1-7; 53, fig. 4, 6
To this species is referred a shell which attains the size of average specimens of Actinopt. communis and is ornamented by radii of alternate or unequal size, crossed by low, concentric erect lamellae. On the anterior surface of the left valve these striae produce a sharp can- cellation and on the large and flat posterior wing radial and concentric lines are of about the same size. On the right valve the wing is can- cellated but on the body of the shell the concentric lines are absent, and the radii are distant and not alternate. This rare shell in the Oriskany seems to agree with the characters of Actinopt. com- munis of the Helderbergian, though it also approaches the Actin- opt. textilis Hall of the same fauna.
OBISKANY FAtJNA OF BECRAFT MOUNTAIN 35
Actinopteria insignis sp. nov.
Plate t, fig. 10-13
In form and proportions this shell resembles a young A c t i n o p t. communis, but its habit is always small and its exterior profoundly cancellated. It is oblique, with large and much depressed posterior wing and small but nasute anterior wing, separated from the body of the shell by a broad sulcus distinctly extending to the umbo. The principal radial striae are strong and rounded, each interspace bearing from one to three very much smaller ones, making a more marked con- trast in the size of the radii than is exhibited by the species Ac tin- op t. communis. These lines are crossed by close concentric lam- ellae cancellating the entire surface, though both series of lines are quite obscure on the posterior wing. To a certain degree this shell presents in miniature the characters of the species Actinopt, textilis, which is mainly distinguished from its associate, Actinopt. com- munis, in the stronger cancellation and interruption of the radii.
The species is not uncommon.
Goniophora sp. ?
This genus is represented by an incomplete valve showing a pretty strong posterior carination and quite regular concentric plications which become broader posteriorly.
Megambonia crenistriata, sp. nov.
Plate i, flg. 15-17
1892. Megambonia helliatriata Clarke, op. cit. p. 413
Megambonia bellistriata Hall, of the Helderbergian, and M. cardiiformis Hall, of the Onondaga limestone are shells in which with present knowledge it is difficult to find a specific difference. The Megambonia occurring in the Oriskany of Becraft mountain approxi- mates this specific type, but is distinguished therefrom in the follow- ing features: it is a persistently smaller shell, none of the observed specimens approaching the dimensions normal to those forms; again, it is shorter and lacks the strongly ovoid contour of the others, a feature specially marked in early stages, where the form was decidedly
86 NEW TOKK STATE MUSEUM
transverse; the byssal groove is profound from the umbo down, and the auricle sharply convex.
The entire surface is covered with fine, elevated radial sti-iae of subequal size and separated by grooves of the same width. Over the auricle and adjoining surface the striae are coarser and are crossed by strongly cancellating concentric lines, which produce projecting processes on the radii, in places taking the form of small spinules. Low varices of growth occur at irregular intervals.
Cypricardinia indenta Conrad
Plate 4, fig. 18-30
1892. Cypricardinia cf. lamellosa Clarke, op. cit. p. 413
For figures of C. lamellosa see Paleontology of New YorTc. v. 3, pi. 49a, fig. 50 a-c; of G. planulata and C. indenta, op. cit. v. 5, pt 1, pi. 79, fig. 1-23
The specific type of Cypricardinia lamellosa Hall, described from small specimens from the shaly (New Scotland) limestone, is con- tinued upward into the Onondaga and Hamilton faunas. The figured examples of the C. planulata of the Schoharie grit show a shell of very large size, possessing the characteristic lamellate surface, but associated with it is a small shell of rather diiferent outline, which it will be diflacult to separate from C. lamellosa. Cypricardinia indenta occurs both in the Onondaga limestone and Hamilton shales. Internal casts of these shells, the usual condition in which they are found, show some slight difference in the character of the broad, con- centric ridges of the surface; but, when the exterior is retained, it appears to be in all cases without material variation in the form, contour and size of the shell (C. planulata excepted). The shells occurring in the Becraft mountain Oriskany are of this persistent type, of medium size, with strong posterior ridge and postcardinal depression, with six to eight concentric lamellae, which are broad and free at the edges and have their surface sculptured by fine lines, radial on the postcardinal slope but en chevron over the umbonal ridge, again becoming radial toward the middle of the shell.
The species is represented in our collections by about a dozen specimens-
OEISKANY FAUNA OF BECRAFT MOUNTAIN 37
Conocardium inceptum Hall (?)
Plate i, fig. 21-33
1857. Conocardium mceptum Hall, Paleontology of New York. 3 : 491
Shell small, obliquely triangular, anterior slope abrupt, posterior surface moderately extended. The heart-shaped anterior surface is some- what convex at first but becomes depressed nearer the margin. The median portion of the valves is prominent, somewhat oblique anteriorly, and its crest is ridged by the remnant of the anterior expansion. The posterior is concave medially, the extremities of the Valves being turned upward.
External surface marked by fine, sharply elevated radial plications in a primary and secondary series, the members of each being of about equal size. These are crossed by finer, concentric erect lamellae making a deep cancelation of the exterior. On internal casts the surface appears to bear libs of which five or six in the posterior region are broad and separated by narrow furrows; over the middle of the valves the ribs are much narrower, eight or 10 in number, and the intervening furrows are broad, sometimes showing traces of intercalary ribs in each. On the posterior slope the ribs become broader again.
The original description was based on very incomplete material, unaccompanied by figures. So far as can be ascertained the Oriskany shell is identical with this Helderbergian species. The aspect of the plication in internal casts is not unlike that of some of the small examples of Conocar. cuneus var. nasutum Hall, of the Schoharie grit* and particularly that of Conocar. concinnum Hall of the Hamilton shales^ to which it corresponds in size, but we are not yet fully acquainted with the exterior of these shells. Average length and width of shell, 10 mm.
"^See Paleontology of New York. v. 6, pt 1, pi. 67, fig. 13. »P1. 68, fig. 26, 27.
3b NEW YORK STATE UrCSElTM
BRACHIOPODS
Oriskania sinuata, sp. nov.
Plate 5, fig. 9-13
1892. CentroneUa sp. nov., Clarke, op. cit. p. 414
Shell of comparatively large size, elongate ovate in outline. Lateral commissure sigmoid. Pedicle-valve convex, strongly ridged medially, with sharply sloping sides. Beak prominent, arched and so incurved as largely to conceal the deltidial plates. Brachial valve flat in the umbonal region. A low median sinus begins at about the center of the valve, becomes wider and deeper over the pallial region and makes a strong linguate depression on the anterior margin. On the interior the brachial valve bears the strong cardinal plate and process peculiar to this genus, and shows deep addiictor impressions and pronounced vascular sinuses over the pallial region.
This shell, which sometimes attains the proportions of Oriskania navicella Hall and Clarke of the Oriskany sandstone at Rondout and Knox, differs from that species in its deeply sinuate brachial valve.
Cryptonella (?) fausta, sp. nov.
Plate 6, flg. 1-8
1892. Cryptmiella, sp. nov., Clarke, op. cit. p. 414
Shell of medium size, elongate oval, commissure nonsinuate. Valves inequiconvex or subequiconvex. Beak of pedicle-valve generally erect and prominent, with well developed cardinal slopes, sometimes arched, partially concealing the deltidial plates. Surface of the pedicle-valve convex, sometimes with a broad median prominence which adds to the convexity; sides gradually sloping; anterior margin nonsinuate. Brachial valve somewhat less convex, slightly depressed in the pallial region; in some specimens ridged medially in the umbonal region.
Interior of the pedicle-valve with muscular scars, obscure vascular sinuses and dental plates developed into a short spondylium.
Surface generally smooth ; sometimes with traces of obscure plica, tions about the margins.
The shells included under this name may with more material be found to embrace two distinct forms, those having nearly equiconvex valves and those in which the pedicle-valve is the deeper and distinctly ridged medially. The
ORISKANY FAUNA OF BECEAFT MOUNTAIN 39
latter have the expression of Centronella more pronounced, while the former suggest the genus Cryptonella. The former also have the beak of the pedicle- valve the more erect. These two expressions, however, seem to grade one into the other. One of the equiconvex shells retains a portion of the interior of the brachial valve and shows the principal part of the loop. There is an elongate hinge-plate which is perforate, and from its anterior edge descend parallel or slightly divergent loop branches which are reflected and upturned at their extremities as though to form an ascending curve, but if this upward branch existed it has been broken oflF, as frequently happens in Cryptonella. The aspect of the apparatus is like that of the genus mentioned, save in this respect, that the descending branches are cemented for their entire length to the apparent floor of the valve. Both replaced shell and loop are retained in silica and it seems probable that this attachment is wholly due to excessive deposition of this substance. The species is not of infrequent occurrence. There is an iindescribed shell of very similar character to this in the New Scotland limestone.
Cryptonella, sp. nov.
This species is represented by two imperfect specimens of a large, convex pedicle-valve whose width is equal to or greater than its length. The surface is somewhat elevated medially in the unbonal region of one of the specimens, while in the other the valve is full and rounded. Umbones depressed ; beak not conspicuous, erect. Surface highly punc- tate with very low and fine radial plications. On the interior the dental lamellae unite to make a short but slightly elevated spondylium, in front of which is a short median septal plate. Length of the valve 17 mm; width 21 mm.
Rensselaeria ovoides Eaton
Plate 5, flg. n-19
1892. Rensselaeria ovoides Clarke, op. cit. p. 414
For other figures see Paleontology of New York. v. 3, pi. 104, 105 ; v. 8, pt 2, pi. 75
Typical examples of this characteristic Oriskany species are quite common in these beds.
40 NEW YORK STATE MUSEUM
Megalanteris ovalis Hall
Plate S, tg. 1»-1«
1892. Rensselaeria suessana? and R. ovalis Clarke, op. cit. p. 414
For other figures see Paleontology of New York. v. 3, pi. 106 ; v. 8, pt 2, pi. 77, fig. 12-22
Specimens are commonly found showing considerable variation in outline, but well characterized in all specific details.
Eatonia medialis Vanuxem 1892. Eatonia raedialis Clarke, op. cit. p. 414
For figures see Paleontology of New York. v. 3, pi. 37, fig. 50, a-y; v. 8, pt 2, pi. 61, fig. 29-35
A few incomplete specimens indicate the presence of this Helder- bergian species in the Becraft mountain Oriskany.
Eatonia peculiaris Conrad 1892. Eatonia peculiaris Clarke, op. cit. p. 414
For figures see Paleontology of New York. v. 3, pi. 38, fig. 21-26; 101, fig. 2; V. 8, pt 2, pi. 61, fig. 17-26
Normal examples of this species are occasionally found. It is a well known species of both the Helderbergian and Oriskany faunas.
Camarotoechia barrandii Hall 1892. RhyncTionella harrandii Clarke, op. cit. p. 414
For figures see Paleontology of New York. v. 3, pi. 103, fig. 3-8 Specimens of the Rhynchonellas observed in these beds have proved to be very xmsatisfactory for study and for the most part, for identifi- cation. A part of a large interior of the pedicle-valve, attaining the full proportions of the figures of the species given in the work cited, is safely referred to this species ; and a few other specimens with less
security.
(?) Camarotoechia fitchana Hall
For figures see Paleontology of New York. v. 3, pi. 101, fig. 1, a, b
A large but imperfect brachial valve bearing about 75 obliquely
angular ribs is referred with reserve to this species.
OEISKANT FAUNA OP BECEAFT MOUNTADT 41
Camarotoechia oblata Hall
Plate 5, fig. 32
For figures see Paleontology of New Yorh. v. 3, pi. 102, fig. 1, 2
A number of large shells possess the numerous sharp, simple ribs
of this species, with its low fold and shallow sinus bearing 10 to 14
of the plications. The distinction between C. oblata and C. plio-
pleura Conrad is not well marked in these shells.
Camarotoechia dryope Billings (sp.)
Plate 5, fig. 20, 21
1874. Rhynchonella dryope Billings, Geol. stir. Canada ; Paleozoic fossils. V. 2, pt 1, p. 37, pi. 3, fig. 1, a-c
A well preserved shell, silicified without distortion, has a sharply- elevated median fold and sinus and angular plications, of which there are four on the fold, three on the sinus and five or six on each lateral slope. The general aspect of the exterior is shown in the figures on plate 5.
On comparison of this species with the figures of Rhynchonella
dryope given by Billings there seems excellent reason for regarding the
forms as identical. The Canadian shell is from Gaspe, limestone no.
8, to the character of whose fauna special reference is made on a
subsequent page.
Camarotoechia, sp?
This shell, of M'hich several distorted specimens have been observed, is of about the same dimensions as the preceding species, but its fold and sinus are less prominent and not angular in front. The ribs are more numerous and not angular but rounded, there being five or six on the fold and sinus and seven or eight on the lateral slopes.
Anastrophia, sp. nov.
The collections contain a single crushed internal cast of an Anastrophia, unlike described species in the very fine plication of the surface. It bears eight ribs on the median fold and 16 on each lateral slope. The genus has not before been recorded from horizons above the Helderbergian.
43 NEW YORK STATE MUSEUM
Coelospira concava Hall
Plate 5, Hg. 23-26
1892. Coelospira sp., Clarke, op. cit. p. 413
For figures see Paleontology of New Yorh. v. 3, pi. 38, fig. 1-7;
V. 8, pt 2, pi. 53, fig. 20-23
This little shell agrees in size and contour with the common
Helderbergian species, but seems never to bear more than 12 plications,
while in normal examples of the species the number may vary from
10 to 16.
The interior of the pedicle-valve bears a short median septum dividing two posterior muscular scars: at the middle of the valve it bifurcates and seems to inclose the impression of an anterior muscular pair, an arrangement similar to that seen in Coel. Camilla of the Onondaga limestone.
This species is less common than Coel. dichotoma.
Coelospira dichotoma Hall
Plate 5, flg. 27-33
For other figures see Paleontology of New York. v. 3, pi. 103, fig. 3 a-c Very abundant, occurring in large, well defined examples through- out the beds. This species is readily recognized both by its size, which at maturity is the largest attained by species of this genus, and by the duplication of its plications. The interior of the pedicle- valve shows a median septum extending for more than one half the length of the shell and dividing an elongate muscular area.
Leptocoelia flabellites Conrad
Plate 5, fig. 33-36
1892. Leptocoelia flabellites Clarke, op. cit. p. 415
For other figures see Paleontology of New York. v. 3, pi. 103b, fig. la-g; 106, fig. la-f; v. 8, pt 2, pi. 53, fig. 40-46, 53
The specimens of this species are in pretty close agreement with typical examples from the arenaceous Oriskany. A difference which is observable in all examples is a slight convexity of the brachial valve, specially pronounced on the anterior region by a deflection of that valve.
0EI8KANY FAUNA OF BECRAFT MOUNTAIN 48
There is, farther, a notable breadth to many of the specimens, which is not so marked in normal individuals. Many of the examples empha- size the close appi-oximation of this species to the Lept. acutipli- cata Conrad, of the Onondaga limestone. This resemblance is particu- larly noticeable in the pedicle-valves, but the broader and more sharply angular plications of the latter species and the more depressed brachial valve constitute reliable differences. Prof. Hall, in 1867, pointed out the similarity of Lept. flabellites and L. acutiplicata, sug- gesting that the two might prove to be identical.
Trematospira multistriata Hall
Plate 6, flg. 1-1
1859. Trematospira multistriata lldiW. Paleontology of New YorTc. 3 : 209, pi. 24, fig. 3a-t ; 28, fig. 5a-f
1892. Trematospira multistriata Clarke, op. cit. p. 414
(?) 1857. Spirifer perforatus Hall, Descriptions of new species of fossils, p. 60
1859. TremMtospira perforata Hall, Paleontology of New York. 3:208, pi. 28, fig. 3 a-i; 8, pt 2, pi. 49, fig. 5, 6
According to the original descriptions, the distinguishing feature in the species above cited is the stronger fasciculation of the plications in T. perforata. It is noted also that in T, multistriata re- peated duplication of the plications may occur. The specimens of Trematospira from the Oriskany agree in general features with the above species, though none have been seen which attain the size often reached by T. multistriata. The plications are sharply angular, with a broader, outer slope, specially near the median fold and sinus. These are sometimes simple throughout their course, but gener- ally are duplicated at irregular intervals, the result of which is a strong fasciculation of the surface, the few early ribs which start at the um- bones maintaining their prominence over the shell. This fasciculate effect is probably more pronounced in the majority of cases than is usual in normal specimens of Tremat. multistriata, but it would be impracticable to divide the Oriskany specimens on the basis of this character. On the other hand, their variation in surface characters serves to indicate the probable unity of those two Helderbergian species.
The surface is finely granulose and punctate.
44 ITEW TOEK STATE MUSEUM
Meristella lentiformis, sp. nov.
Plate 6, fig. 5-11
1892. Meristdla, sp. nov., Clarke, op. cit. p. 414
Meristella lenta Hall, is a diminutive species, wliicli lias been reported only from the Oriskany sandstone at Cayuga and De Cewville Ont.' It is of peculiar form, having the pedicle-valve broadly concave in the pallial region and the brachial valve highly con- vex medially, the sides sloping from this median prominence with a gently concave surface. In respect to this form, which is an extreme expression of a tendency frequently exhibited among the more equicon- vex Meristellas, the species approaches the Meristella (Pen- tagonia) unisulcata Conrad, of the Onondaga and Hamilton beds. In the structure of the brachidium both of these shells have proved to be genuine Meristellas. The most abundant representative of this genus in the Becraft mountain Oriskany is a shell which nearly approaches Mer. lenta in contour, with some noteworthy differences, not the least being its considerable size. We may characterize the species as follows: shell unequally convex; outline transversely oval; pedicle-valve with short incurved beak and narrow cardinal slopes bordered by obtuse cardinal ridges diverging from the beak. Umbo slightly convex or flat, the surface sloping to the sides very gradually. A median sinus starts at the umbo and rapidly broadens, producing a general depression in the pallial region, which is rather sharply deflected. The sinus is produced into a linguate extension at the anterior margin. The general flatness of this valve is more marked in young shells, the anterior deflection becoming prominent with the increase of age. The brachial valve has a full beak curved into the delthyrium of the oppo- site valve, and is elevated medially into a broad ridge-like concavity terminating in a fold on the anterior margin. The lateral slopes are gently concave. The surface of both valves is smooth or bears only concentric growth lines.
On the interior the apophyses and impressions are those characteriz-
*For figures of this species see the original description, Paleontology of New York, 4:420, pi. 63, fig. 19-22 and also v. 8, pt 2, pi. 44, fig. 15-lS.
OEISKAHT FAUNA OF BECRAFT MOUNTAW 45
ing the genus. Particularly well developed is tlie broad, flabellate muscular scar of the pedicle-valve and the median septum of the bra- chial valve, extending for more than half the length of the shell.
The brachial valve resembles in its less extreme conditions that of the associated specimens of M. lata, but the shell taken in its entirety- can not be confounded with any other species.
Meristella lata Hall
1859. Meristella lata Hall, Paleontology of New York. 3 : 431, pi. 101, fig. 3, a-in
1892. Meristella of. laevis Clarke, op. cit. p, 414
The specimens which represent this species are of very much smaller size than the forms of this Oriskany shell which have been described, but they show no wide departure therefrom in other respects.
Meristella (?) vascularia, sp. nov
Plate 6, fig. 13-14
Among these fossils are frequently found internal casts of large pedicle-valves of an elongate Meristella- like form with broad median sinus developed over the anterior region. Notwithstanding that these specimens are not uncommon, I have not been satisfied of the charac- ter of the brachial valve to be referred to them, nor has it been possible to get a very clear conception of the exterior of the shells. These interior casts differ from that usual to Meristella in the following respects. Very prominent dental lamellae are developed by convergence and union into a strong spoon-shaped process, which fills the umbonal region and rests on the bottom of the valve, its anterior edge being free. The corresponding structure found in the Meris- tellas is of diminutive size compared with this. In front of this process lies the elongate, often obscure central nuiscular scar, which in Meristella is much more strongly developed and constitutes the most conspicuous feature of the interior. From the mai-gins of the spondylium, even traversing the central scar, diverge strong radial grooves which cover the umbonal and median regions of the valve, disappearing about the margins. These features are uniform in all specimens, though the vascular lines are less conspicuous in young sheEs.
46 KEW YORK STATE MDSEUM
The exterior of the shell, preserved in part on one silicified speci- men, bears low and distant radial striae, which are crossed by veiy fine and crowded concentric lines. Even with our present imperfect knowl- edge the species is clearly distinguished from all known Meristellas, but it is still far from certain that the shell is to be referrrd to this genus.
Spirifer arenosus Conrad
1892. Spirifer arenosus Clarke, op. cit. p. 413
For figures see Paleontology of New York. r. 3, pi. 98, 99, 100 ; V. 8, pt. 2, pi. 29, fig. 1-4; 80, fig. 3-7
Specimens of this characteristic Oriskany shell are not at all uncommon here and attain the considerable size and transverse form of the species as it occurs in the higher beds of this state. At Cum- berland Md., and at Cayuga Ont., the species is generally much shorter on the hinge and more elongate medially, but this expression has not been observed among the specimens from Becraft mountain.
No complete account has ever been given of the nature of the surface configuration of this shell, and some of the fine external molds from the decomposed silicious limestone show the characters with exac- titude. The plications are broad and distinctly flattened above, with very narrow interspaces, and the grooves bear the finest radial striations which are not interrupted by concentric lines. This is such a char- acter as is seen on many of the upper Siluric Spirifers, but is not usual among the Aperturati till after the close of the Devonic.
Spirifer murchisoni Castelnau
Plate 6, flg. 26-30
1843. Spirifer murchisoni Castelnau. Essai syst. silur. de VAmer. septentr. p. 41, pi. 12, fig. 1, 2
1859. Spirifer arrectua Hall. Paleontology of New York. 3 : 422, pi. 97, fig. 1,2
1892. Spirifer arrectus Clarke, op. cit. p. 413
Characteristic specimens are very abundant throughout these beds. External molds display very perfectly the nature of the surface, which has never been quite accurately given. The broad, subangular ribs are
ORISKANY FAUNA OF BECEAFT MOUNTAIN 47
crossed by regularly concentric fimbriae of short spinules, and between these rows the surface is studded with granules so regularly arranged that they seem to have been produced by the breaking up of radial lines by intersections.
Very recently Dr H. Scupin has discussed the variations of this specific type occurring in the two Americas and South Africa^ restrict- ing the term S p. a r r e c t u s to the forms figured by Hall in the work cited, excluding figures le and If on plate 97. From a consideration of these figures only it might seem that there is a varietal difference in the specimens here referred to, the one form having five or six lateral plications and a more prominent median fold, while the latter (fig. le and If) has seven or eight latei'al plications, an apparently lower median fold, and seems to be a shell of larger habit. It would be a difficult matter to separate the specimens of this species occurring in the Oriskany sandstone on the basis of these features. The degree of plication is variable within the limits specified, and the prominence of the median fold as well as the apparent size of the shell dependent on the mode of retention. Determinations based on none too good illustrations and fortified mainly by the study of internal casts will not prove of practical usefulness in this case. Among the forms of this shell found in the Oi'iskany fauna the transitions from one expression to the other are so frequent as to make it practically certain that these differences are altocrether fugitive.
I adopt without hesitation Castelnau's early term, S p . m u r c h i - s o n i for this species, following Mr Schuchert's suggestion ; for though the figures given by Castelnau are for the most part extremely obscure, no doubt can attach to his intentions and demonstration iu this case.
In accordance with his determination, Dr Scupin proposes to restrict the term a r r e c t u s to shells represented in Paleontology of New Yorh as cited, exclusive of le and If, and regards these identical with Sp. antarcticus Morris and Sharpe, a shell collected by Darwin in the Falkland islands. These he would term Sp. arrectus var.
'Ueber exotisclie, ziir gruppe des Spirifer primaevus gehorige Formen ; Zeitschr. der Deutsch. geol. Gesselsch, 1899. 50 : 462.
48 KEW YORK STATE MUSEUM
antarcticus, including therewith Sp. chuquisaca Ulrich (Bol- ivia), Sp. orbignyi Morris and Sharpe (Falkland Islands) and S p. capensis v. Buch (South Africa), In view of the characters and variability of S p . m u r c h i s o n i in its typical localities it seems probable to the writer that a knowledge of all these lower Devonic shells (including Sp. hawkinsi Morris and Sharpe, Falkland islands) which is not so fully based on the characters of the internal cast, will prove them to belong for the most part to Sp. murchisoni.
Spirifer saffordi Hall
Plate 6, flg. 23-85
1859. Spirifer saffordi Hall, Paleontology of New York. 3 : 203, pi. 28, fig. 2, a-b
1892. Spirifer of. fimhriatus Clarke, op. cit. p. 413
This is less common than either of the other species of Spirifer. Squeezes show that the low, sparse libs are crossed by distant, con- centric rows of greatly elongated, vertical spine-bases. These are produced both above and below the actual attachment of the spinules, the open- ings of the latter being seen at aboiit the middle of each supporting ridge. From the position and direction of these hollow bases, it would seem that the spinules were either erect or inclined backward.
Metaplasia pyxidata Hall
1859. Spirifer pyxidatus Hall, Paleontology of New Yorh. 3 : 428, pi. 100, fig. 9-12
1892. Spirifer pyxidatus Clarke, op. cit. p. 413
For figures see Paleontology of New York. v. 8, pt 2, pi. 39, fig. 19-22
This peculiar shell, which is common in the Oriskany at certain other localities, specially at Cayuga Out., and is found also in the Onon- daga limestone, is not of infrequent occurrence at Becraft mountain.
OBISKANY FAUJNA OF BJiCKAii' MOUNTATN 49
Cyrtina varia sp. nov.
Plato 6, flg. 15-2a
1892. Cyrtina rostrata and C. cf. dalmani Clarke, op. cit. p. 414 The specimens of Cyrtina in this fauna are quite variable in size and proportions. There is a small, tetrahedral form with high, slightly concave and relatively short cardinal area, v^^hich suggests C y r . dalmani Hall of the Helderbergian fauna, but is of larger size with narrower plications (5 or 6 on each lateral slope) and broader intervals. This form passes into one with very elongate cardinal area, like some of the forms from the Oriskany sandstone which have been regarded as young of Cyr. rostrata Hall.* There is again a large shell which sometimes attains the full size of Cyr, rostrata, with slightly arched, cardinal area and rather short hinge-line. These shells bear from 5 to 8 plications on the lateral slopes, have the median fold depressed or slightly furrowed on top, with a simi- larly flattened median sinus. The surface in all is finely pustulose and crossed by sharp, concentric lines. As there is at present no satisfactory basis for separating these various shells, and as they can not all be referred to any of the described species, they are here considered as individual expressions of the same species.
Chonetes hudsonica sp, nov.
Plate 7, flg. l-«
1892. Chonetes sp. n., Clarke, op. cit. p. 413
This is the only normally convex Chonetes found in this fauna. The shell is of medium or small size, transverse in outline ; hinge-line marking the greatest width of the shell ; lateral margins subparallel for a short distance and rounding rather abruptly to a nearly trans- verse anterior margin. Surface of the pedicle-valve quite uniformly convex, with a faint median sinus seen only over the anterior portion of the valve. The surface striae are fine, round and close together, with very narrow interspaces. They increase rapidly and irregularly by bifurcation and implantation. Very fine, concentric
^See Paleontology of New York. v. 3, pi. 96, fig. 1, a and b.
50 mEW YOEK STATE MUSEUM
lines are sometimes visible with favorable preservation. The cardinal spines are two or three in number on each side of the beak and are directed outward.
On the brachial valve a fold to correspond to the obscure median sinus of the pedicle-valve is not always to be seen. So far as ob- served, the multiplication of the striae of this valve seems to be wholly by bifurcation. With respect to their interior characters, both valves present normal structure with a considerable development of the median septum in the pedicle-valve.
This species is quite common and is identical with or closely allied to a shell known to occur in the New Scotland limestone of the Helderbergian in Albany county.
The comparison of these shells with specimens of Ch. melonica from limestone no. 8 of the Gaspe series, at Grand Gr6^'e on the bay of Gaspe, Quebec, shows that the latter is a larger shell with a charac- teristic parabolic outline and a more profuse striation.
Ch. hudsonica however occurs in the Gaspe sandstones associ- ated with Spirifer gaspensis, Leptostrophia blainvillii Billings, etc.
Chonostrophia complanata Hall (=Ch,onetes danosoni Billings, Oeol. sur. Canada; Paleozoic fossils, 2:18. 1874)
Plate 7, flg. 1-13
1859. Ghonetes oomplanatus Hall, Paleontology of New York. 3 : 418, pi. 93, fig. 1, a-d
1892. Chonostrophia sp. n. Clarke, op. cit. p. 413
This shell seems never to attain the size of the normal Oriskany form, but it has in general the same outline and seems to present no stable features on which a distinction from this species can be based. The striation of the surface is extremely fine and when well preserved is distinctly fasciculate, particularly about the beaks. Usually however this is more or less obscured over the body of the shell, the striae •becoming subequal and often very faint. At times a still finer con- centric striation is apparent. The reversed convexity is quite strongly
ORISKANY FAUNA OF BECKAFT MOUNTAIIT 51
developed, perhaps more so than is usual with the upper Oriskany shell.
It is difficult to find any differences between this shell, specially in its smaller form and the Chonetes dawsoni Billings from the Gaspe sandstones. Both forms are but slight departures from the normal lai-ge expression of the shell depicted in the original illustration of C. complanata.
Between this species and the Chonostr. helderbergia Hall and Clarke of the Helderbergian, there seems but little difference ex- cept in the more uniform striation of the latter and its slighter con- vexity, but in the Chonostr. reversa Whitfield, of the Onondaga the differentials are the distinctly fasciculate striation, the elongate rather than transverse form and the diminutive size.
Anoplia nucleata Hall
Hate 7, ng. 14
1859. Leptaena ? nucleata Hall, Paleontology of New York. 3 : 419, pi. 94, fig. 1 a-d
1892. Anoplia nucleata Clarke, op. cit. p. 413
For other figures see Paleontology (^ New York. v. 8, pt 1, pi. 15, fig. 17,18 and pi. 20, fig. 14-17.
This little species is far more abundant here than in the arenace- ous Oriskany of New York. It occurs also in some abundance in rocks referred to the Oriskany in Jones county, Illinois.
Orthothetes becraftensis sp. nov,
Plate 7, flg. 15-28
Shell small, suborbicular or elongate in outline. Pedicle-valve erect at the beak, umbonal region generally sloping directly or with low convexity to the peripheral margins ; sometimes slightly depressed about the umbo. Brachial valve depressed at and about the beak, becoming convex over the median and anterior regions.
• Surface of both valves covered with strong, rounded striae in- creasing by implantation, new striae generally appearing in successive cycles. The surface also bears exceedingly fine, concentric lines which
62 NEW YORK STATE MUSEUM
are visible in the interspaces but seldom cross the radial striae. Con- centric varices of growth are also frequent, specially near the margins.
The cardinal area of the pedicle-valve is triangular, broad and erect, seldom showing distortion. In but a single instance has attach- ment been observed and that is the young shell figured on plate 7, which adheres by its entire outer surface to a valve of Meristella and is associated with Autodetus, Hederella and some other parasitic growths. The deltidium is pronounced. On the interior the markings are those characteristic of the genus ; the brachial valve bears an erect, continuous cardinal process, divided into two lobes, each grooved on its outer face. The lateral walls of this process are continued inward to form the strong dental sockets.
This very common species has no close ally in the Devonic faunas of the neighboring region. The Orth. woolworthana and Orth. deformis of the Helderbergian are large shells with a much finer surface striation, and perhaps the nearest approach is found in the Orth. arctostriata of the Hamilton shales, from which a difference will be found in outline and character of surface. Most closely allied also to O. becraftiensis is an undescribed species in the Gaspe sandstone.
Hipparionyx proxtmus Vanuxem
1842. Hipparionyx proxtmus Yanuxem, Geology of New York', repH on third dist. p. 124, fig. 29, no. 4
1892. Hipparionyx proximus Clarke, op. cit. p. 413
The specimens of this well known Oriskany species which have been obtained are of large size and characteristic in all details.
Stropheodonta lincklaeni Hall
Plate 7, flg. 37
1859. Strophodonta lincklaeni Hall, Paleontology of New York. 3:415, pi. 93, tig. 2, 3
1892. Stropheodonta lincklaeni Clarke, op. cit. p. 413
This species was not originally very clearly defined on account of the imperfection of the material, but the name has been generally applied to plane or slightly convexo-concave stropheodontids with a very
ORISKANY FAUNA OF BECEAFT MOUNTAIN 53
finely radiate surface. Indeed the exterior appears at first view to be almost smooth and shows numerous concentric growth-lines, but fine striae are invariably present, so fine and numerous as to produce a striated effect without a very clear definition of individual lines. The aspect of the species is sufficiently peculiar to distinguish it readily from other fonns.
Stropheodonta lincklaeni was described from the Oriskany sandstone of Albany and Schoharie counties. The species is not com- mon at Becraft mountain.
Leptostrophia magnifica Hall
Plate 7, flg. 36
1859. Strophodonta rruignifica Hall, Paleontology of New York. 3:414, pi. 93, fig. 4; 94, fig. 2a-d ; 95, fig. 8
1892. Leptostrophia magnifica Clarke, op. cit. p. 413
A few specimens which apparently represent this Oriskany species have been observed, though none of these attain the normal propor- tions; yet they are large, perplane shells, surpassing the dimensions of Lept. becki and conforming in external and internal features with Lept. magnifica, to which they are provisionally referred.
Leptostrophia oriskania, sp. nov.
Plate 7, flg. 29-33
1892. Leptostrophia cf. hecki, and L. perplana Clarke, op. cit. p. 413 The most abundant fossil in these rocks is a species of Lepto- strophia of uniformly small size and somewhat variable in the aspect of the exterior. In the work above cited I was disposed to regard some specimens of this, in which the concentric corrugations of the surface are most pronounced, as representing the Helderbergian species Lept. becki, though their uniformly smaller size was recognized; others, having the surface almost or wholly devoid of coi'- rugations, were referred to the middle Devonic species L. perplana Conrad. On a review of the material it has become exndent that all have features common to both of those mentioned and represent but a single species. It might be looked on as a small variety of Lept.
b4 NEW YOEK 8TA*rE MUSEUM
b e c k i , were it not for the great variability of the exterior, and perhaps in all respects its structural affiliations are closest with that shell; but it never attains the size of that species, while its persistent small size forms one of its most stable characters.
Shell of medium size, very gently concavo-convex. Hinge-line straight, attaining the greatest width of the shell; at full growth very slightly produced at the cardinal extremities, but in young stages with quite decided extensions. Cardinal area narrow and mainly confined to the pedicle- val ve ; striated horizontally and crossed vertically by ridges which make themselves apparent on the hinge-line as denticula- tions. The area is crossed by a narrow delthyrium which is generally covered. Surface of the pedicle-valve covered with fine, rounded striae which increase rapidly by intercalation. At intervals on the surface, usually distant, are sharply defined concentric varices or growth- lines. Accompanying these are concentric corrugations, sometimes so pronounced and regular that the surface suggests that of Lep- taena rhomboidalis, but generally finer and irregular. These may extend over the entire surface or be best developed in the um- bonal and median parts of the shell; or they may be very obscure and often, when the concentric varices are frequent and strong, may be altogether indistinct. Along the hinge-line the wrinkles are ob- lique, being parallel to the extended extremities of early growth stages.
On the brachial valve the ornament is of quite the same charac- ter. The apophyses and scars of the interior are those prevailing in this genus. The cardinal process is bifurcated, and the posterior face of each division is concave. From the base of this process diverge short, lateral ridges which are highly pustolose, between them lying a shorter median ridge. In both valves the muscular scars are indistinct.
Dimensions. Full grown shells seldom exceed a length of 20 mm
and a width of 25 mm.
Brachyprion majus, sp. nov.
Plate 8, flg. 8-13
1892. Stropheodonta, sp. n. A. Clarke, op. cit. p. 413
There are two species of this genus, Brachyprion, in this fauna, and both present some similarities to the species of the Helder-
ORISKAKY FAUNA OF BECRAFT MOUNTAIN 55
bergian S t rop he odon t a varistriata (Conrad) Hall. While both complete all the stages of growth represented by that species, they alike pass beyond those and attain adult characters not exemplified in species of earlier date. Brachyprion varistriatum is a com- mon species in the Manlius limestone, and, though usually of small size in the former, sometimes assumes considerable dimensions. Prof. Hall has described as a variety of this species, Stroph. varistriata, var. arata, from "a crystalline band of the shaly limestone of the lower Helderberg group; Becraft's mountain, Hudson", its differential being found in the strong, sharp, subequal striae. The ornament of the species, Brach. varistriatum, specially in its smaller forms, is that of the well known Rafinesquina alternata of the Trenton limestone and many coeval and later shells; that is, it consists of coarser, filiform striae alternating with a group of subequal, finer ones. This character is well expressed on specimens of Brach. majus through early stages and till the maximum of convexity is attained and the pronounced deflection to the anterior margin begins. Thence forward this character becomes modified. In the other species, Brach, schuchertanura, however, early stages do not exhibit this arrange- ment of the ornament, but start with the surface characters of the var. aratum Hall, retain it for a brief period only, the resultant orna- ment being distinct from that in any of the allied shells. No stronger argument on behalf of the specific distinction of the var. arata could be adduced.
With regard to the peculiar structure of the hinge which charac- terizes the genus Brachyprion, both of these Oriskany shells have it well developed ; the delthyrium is open and the denticulatious of the hinge-line are small and extend only about half way to the cardinal angles.
Shell of quite large size at maturity. Hinge straight and having the full width of the shell ; marginal outline elongate lunate. Surface of the pedicle-valve gently convex but strongly sloping in the umbonal region, the greatest elevation and convexity of the valve being attained in front of the center and following a line parallel to the margin.
56 NEW YORK STATE MtlSEUM
Thence forward the slope is much more abrupt. The brachial valve conforms in contour with its opposite.
The cardinal area is narrow, the denticulations on the pedicle-valve quite small.
The oi'namentation of the valves is, as we have just observed, a series of alternating filiform striae with a group of two to six smaller striae in the intervals. These striae multiply rapidly by bifurcation and intercalation, and the fascicles become increased with considerable irregularity. Immature shells of the species may show only these characters and in this condition represent the normal state of Brach, varistriatum, but at maturity the high convexity and abrupt an terior slope is added, and on this anteiior surface the striation is modified by the rapid increase in number of the larger striae and diminution in size and number of the intervening striae. Thus the aspect of the striation becomes much more uniform on these later parts of the shell. It is to be observed, however, that this modification does not always set in at the same period of shell growth, and we may therefore have shells of incomplete growth showing these adult characters outside of the umbonal region and, on the other hand, large shells with adult convexity, retaining the fasciculate striation of early stages. We observe in the species Brach. schuchertanum the presence of an indistinct and irregular median fold and sinus on pedicle and brachial valves, and some trace of a like feature is to be occasionally seen on old shells of this species. The striae are crossed by very fine, elevated, concentric lines which distinctly cancellate the surface.
Brachyprion ma jus is not an uncommon member of this fauna.
Brachyprion schuchertanum, sp. nov.
Plate 8, flg. 1-7
1892. St/ropheodonta cf. radiata Clarke, op. cit. p. 413
Shells at full size as large or larger than in Brach. majus. Convexo-concave, rising from the umbones regularly to the middle or antemedian portion of the pedicle-valve and sloping thence with uni-
OEISKANY FAUNA OF BEORAFT MOUNTAIN 57
formity. The great convexity and abrupt slope of Brach. ma j lis are absent. Along the middle the brachial valve is depressed by a longitudinal sinus widening anteriorly, seldom well defined at its edges. This is well marked on the interior of the valves and shows itself on the exterior of the pedicle-valve as a broad median ridge passing without definition into the lateral slopes. Hinge-line straight and as long as the width of the shell. Umbo of the pedicle-valve convex and prominent.
The surface of early growth stages is marked by a few coarse, strong, subangular ribs with a few secondary striae. These rapidly increase by division and implantation, so that eventually but , little trace of fasciculate arrangement is left, and the surface becomes equally, coarsely and closely striated. These striae are crossed by fine concentric lines, which are sharper than those in Brach. ma jus, and present a different aspect, on account of the absence of the finer radiating striae which they cancellate in that sjiecies. Cardinal and internal characters as in Brach. m a j u s , the row of cardinal denticulations being somewhat larger than in that species.
Early stages of this species are, as observed, suggestive of Brach. aratum Hall, and in some cases recall specimens of S t r o ■ pheodonta demissa Conrad, from the Hamilton shales.
Leptaena rhomboidalis Wilckens
1892. Leptaena rhomboidalis Clarke, op. cit. p. 413
The shells of this species are common and conform to the type of this shell occurring in the Helderbergian and Ulsterian rather than to the large and ventricose form of the Oriskany which has been described by Hall as Strop ho mena rugosa, var. ventricosa,
Dalmanella perelegans Hall
1859. Orthis perelegans Hall, Paleontology of New York. 3:171, pi. 13,
fig. 4-12 1892. Orthis perelegans Clarke, op. cit. p. 413
Shells which can be ascribed to this species have usually under- gone some compression which obscures in some degree their specific
58 NEW YORK STATE MUSEUM
characters and at times produces a resemblance to the allied shell, Dalm. subcarinata. Satisfactory evidence of the presence of the latter, is however, still wanting. Both are characteristic brachiopods of the New Scotland beds.
Rhipidomella oblata Hall
Plate 8, fig. 14, 15
1857. Orthis oblata Hall, Paleontology of New York. 3:162, pL 10 1892. Orthis cf. oblata Clarke, op. cit. p. 413
This Holderbergian species is represented by specimens of rather small size and of not very frequent occurrence.
Crania pulchella Hall and Clarke
Plate 8, flg. 16-18
1892. Crania pulchella Hall and Clarke, Paleontology of New York. V. 8, pt 1, p. 180, pi. 4, fig. 3
1892. Crania sp. n., Clarke, op. cit. p. 413
The specimens of this species from Becraft mountain are frequently of large size and have the radial plications very sharply developed. These are more numerous than in the typical specimens of the species, but, as they rapidly increase with additions to the diameter of the shell, there is no reason for not regarding both forms as of the same specific type.
The original of Cr. pulchella is from the New Scotland limestone, near Clarksville N. Y.
Crania of. bella Billings
Plate 8, flg. 19, 20
1874. Crania hella Billings, Geol. sur. Canada ; Paleozoic fossils. v. 2, pt 1, p. 15, tig. 5
1892. Crania sp. n. Clarke, op. cit. p. 413
This is a generally small shell with smooth surface, upper valve more or less convex, generally concave on the posterior slope, with apex directed slightly backward ; sometimes with the posterior margin transverse. It approaches very closely to the species cited, from the
OEISKAKT FAtTNA OP BECRAFT MOUNTAIN 59
Gaspe limestone no. 5, termed by Billings "Passage beds" from the "Upper Silurian" (Lower Helderberg) to the "Lower Devonian" (fauna mainly of Oriskany species). The shell is less common in the Becraf t mountain fauna than C. pulchella.
Pholidops terminalis Hall
Plate 8, flg. 23-25
1859. Pholidops terminalis Hall, Paleontology of New York, 3:490, pi. ]03b, fig. 8a-d
1867. Pholidops arenaria Hall. Idem., 4:413, pi. 3, fig. 24
1892. Pholidops terminalis Clarke, op. cit. p. 413
Sharply defined impressions of this species are very common.
The original of Ph. terminalis was from the Oriskany sand- stone of Cumberland Md., and thut of Ph. arenaria from the same
formation at Knox N. Y.
Pholidops sp.?
Plate 8, flg. 21, 22
1892. Pholidops sp. n., Clarke, op. cit. p. 413
A few specimens have been seen of a very small Pholidops, unlike Ph. terminalis and the group of species to which it belongs, with terminal beaks, but representing the more common expression of the genus with subcentral beaks, represented by species which range through the Paleozoic rocks from the lower Siluric into the Carbonic.
Lingula cf. rectilatera Hall 1869. Lingula rectilatera Hall, Paleontology of New York. 3 : 156, pi. 9, tig.
6, 8 1892. LvngvXa sp., Clarke, op. cit. p. 413
A single incomplete example retains the parallel sides and trans- verse anteiior margin of this species described from the New Scotland limestone.
BRYOZOA
Rhombipora rhombifera Hall See Paleontology of New York. 6:18, pi. 11, fig. 15,17-20; pi. 23, fig. 11,12 A few twigs of a Rhombipora which agree in size and struc- ture with this Helderbergian species have been observed.
60 NEW YORK STATE MUSEUM
Stictopora sp?
A few specimens of this genus have been observed, but none have the exterior well enough preserved to justify an attempt at their identification, though in general aspect as well as in the character of the cells so far as ascertainable the species is very closely allied to St. granulata Hall of the Helderbergian,
Unitrypa lata Hall
1887. Fenestella {Unitrypa) lata Hall, Paleontology of New York. 6:136, pi. 53, fig. 1-10
This species was described from the Onondaga limestone of Wal- pole Ont. It is not uncommon in the Oriskany of Becraft mountain.
Unitrypa acclivis Hall 1887. Fenestella ( Unitrypa) acclivis Hall, Paleontology of New York. 6 : 138,
pi. 52, fig. 16-23. Not common. The originals were from the Onondaga limestone of Walpole Ont.
Lichenalia cf. crassa Hall
For figures of L. crassa, see Paleontology of New YorJc. v. 6, pi. 11, fig. 21, 22 Specimens which seem to agree with this Helderbergian species are occasionally found.
Polypora separata Hall (?) See Paleontology of New YorJc. 6 : 166, pi. 39, fig. 10, 11 Specimens very similar to this species but having larger fenest- rules are common. Polypora separata was described from the Onondaga limestone of Walpole Ont.
Polypora, sp. indes.
Polyporella cf, compressa Hall Of the Helderbergian.
OEISKANY FAUNA OF BECRAFT MOUNTAIN 61
Isotrypa, sp. indes.
Reteporina, sp. indes.
Fenestella biseriata Hall (?) See Paleontology of New York. 6:113, pi. 42, %. 16-18 Fronds having the characters of this species are occasionally found The originals of the species were from the Onondaga limestone at Cherry Valley N. Y.
Hemitrypa columellata Hall
1887. Fenestella {Ilemitrypa) columellata Hall. Paleontology of New York. 6:146
This species, described from the Onondaga limestone of Walpole Ont., is occasionally found in the Becraft mountain Oriskany,
Hederella magna Hall and Simpson
Plate 9, flg. 10
1887. Hederella magna Hall and Simpson, Paleontology of New York. 6 : 280, pi. 65, fig. 15
To this species is referred a Hederella charactei-ized by its short, stout, strongly rugose and somewhat irregular cells, erect at their extremities, growing in a double series which proceed from a central stock generally in part concealed by overgrowth. The cells are larger than in any of the other species here found.
The onginal of this species was from the Hamilton shales of
York N. Y.
Hederella arachnoidea, sp. nov.
Plate 9, fig. 11
This is the smallest of the species here observed, the zoarium being very fine, creeping in an irregidar manner over the surface of attachment, genei'ally showing the biserial stock, but this is often obscured by frequent and irregular branching. The cells are narrow, often flat- tened, branching taking place at quite distant intervals but alternately on opposite sides. The species may be distinguished from H e d . g r a c i 1 i o r by its finer, more elongate cells, its more distant branch- ing and much more diffuse and irregvilar zoarium.
62 JTEW YORK STATE MUSEUM
Hederella ramea, sp, nov.
Plate 9, flg. 9
A very graceful zoarium consisting of a primitive stock from which branches arise on either side at distant and highly irregular intervals, the secondary branching arising from the principal branches in such a way as to produce a palmate frond. The cells are subcylindric, smooth and procumbent at their extremities.
Hederella gracilior, sp. nov.
Plate 9, flg. 10
In this species the zoarium attains about the size of that in H e d . filiformis Hall and Simpson of the Hamilton shales, but the form of the colony is less diffuse, the double series of cells retaining a compact form and the entire zoarium being a miniature of Hed. magna. To the difference in size of the cells in these two species are added as distinguishing characters the flattened and less rugose condition of the cells and their more slender and regular form.
CRINOIDEA
Edriocrinus becraftensis, sp. nov.
Plate 9, fig. 12, 13
The calyxes of this species may be distinguished from those of Edr. sacculus Hall from the Oriskany sandstone of Cumberland Md. in their elongate, much moi'e slender and very gradually enlarging form, and generally quite small size. They are blunt but not broad at the base and enlarge upward with gently incurving sides. In one in- stance only has the upper edge of the calyx been observed, and ex- cept for this edge no specimen shows traces of the component plates.
The casts of the calyx are not infrequent.
ANTHOZOA
Zaphrentis sp.
These fossils occur as casts of the calyx. Two forms are evident, one, the smaller, conforming to the characters of Zaphrentis, the larger differing from this structure in the presence of double series of tubercles in the lamellar interspaces.
ORISKANY FAUNA OF BECEAFT MOUNTAIN 63
(?) Ptychonema helderbergiae Hall
See Paleontology of New York. 6 : 15, pi. 9, fig. 16, 17
Several specimens have been found which have a ramose stock and attain the proportions of this species both in size of stock and cell apertures.
Vermipora streptocoelia, sp. nov.
Plate 9, ag. 7, 8
Ramose twigs of from 8 to 12 mm diameter are bundles of tubes like those of Vermipora, but, instead of having a direct course out- ward from their point of growth, as in the known species of the genus, these tubes are exceedingly irregular, wandering about in serpentine courses as they approach the termination, but appearing to be straighter within the substance of the stock. The material illustrating this peculiar form is not very favorably preserved, and the species will be an interesting subject for farther study,
Vermipora serpuloides Hall, var.
See Paleontology of New York. 6 : 5, pi. 2, fig. 24-31
Vermipora serpuloides of the Helderbergian differs from this species in the smaller size and greater number of its tubules. The colony is slender and branching. With better material it is probable that this form would prove a distinct species.
Cladopora smicra, sp. nov.
Plate 9, flg. *-6
Small and sparsely branching colonies with stems from 3 to 5 ram in diameter, bearing small, very oblique cells in 6 to 8 vertical rows. The apertures of these cells are much compressed, the upper surface being broadly arched and the under surface being more or less excavated in the substance of the stock. On the older parts of the stem the cells are reduced in form to scales covering circular pits. The species is distinguished from Clad, styphelia by its slender form and much less conspicuous cells. The species exists also in the Onondaga limestone of western New York.
64 NEW rORK STATE MUSEUM
Cladopora styphelia, sp. nov.
Plate 9, fig. 1, 2
There are found occasionally twigs of Cladopora of considerable size, bearing very large oblique cells which are arranged more or less irregularly in 8 to 10 vertical, alternating rows. These stems have a diameter of 6 to 8 mm and the apertural diameter of the cells is from 2 to 4 mm. The species is readily recognized by the size of the cells and their angular projection at their apertures, which gives the colony a very rough exterior.
Aulopora cf. schoharie Hall See Paleonlology of New Torh. 6 : 3, pi. 2. fig. 1-6
The few specimens of Aulopora observed are very closely allied to this Helderbergian species, but appear to be persistently of larger size.
Monotrypella arbusculus Hall and Simpson
1887. Chaetetes {Monotrypella) arbusculus Hall and Simpson, Paleontology of New Yorh. 6:12, pi. 9, fig. 1-8
Of this Helderbergian species a few very characteristic examples have been observed.
HYDROZOA
Dictyonema cf. splendens Billings
1874. Dictyonema splendens Billings, Geol. sur. Canada; Paleozoic fossiU. V. 2, pt 1, p. 12, fig. 2, 2a
Mr Billings described his species from the lowest of the Gaspe series of limestones (no. 1) which, according to his determinations, con- tains a fauna with notable Helderbergian affiliations. This species does not agree closely with the species known from the New Scotland lime- stone (D. crassum Girty), but is comparable to a form observed only in some fragments from the calcareous Oriskany.
OEISKAKY FAUNA OF BECRAFT MOUNTAIN
65
VERTICAL RANGE OF THE SPECIES OF THE ORISKANY FAUNA AT
BECRAFT MOUNTAIN
1 Dalmanites (Synphoria)stemmatu8 C.
2 D. (S.) stemmatus var. convergens V.
3 D. phacoptjx H. & C
4 D. bisignatns C ,
5 Phacops correlator C
6 P. logani H
7 Cordania becraftensis C
8 C. hudsonica C.
9 Cjphaspis minuscula H.
10 Proetus conradi II
11 Acidaspis tubereulata Conrad
12 Lichas cf. pustulosus H.
13 Homalonotus »pA
14 Beyrichia sp.\
15 Plumulites
16 Annelid teeth
17 Autodetus beecheri C.
18 Spirorbis assiinilis C
19 Cornulites cingulatus II
20 Tentaculites elongatus H
21 T. (?) acus G
22 Connlaria sp
23 Eellerophon sp
24 Cyrtolites expansus H.
25 Pleurotoniaria sp
26 Diaphorostoma desniatum C
27 D. ventricosum Conrad
28 Strophostylas expansus Conrad . . . .
29 Orthonychia tortuosa H
30 Platycerae cf. gebliardi H
31 P. nodosum Conrad
32 Pterinea ep.'i
33 Pterinopecten subequilatera H
34 P. proteus C
35 P. signatus C
36 P. pumilus C
37 Aviculopeeten sp
38 Lyriopecten sp
39 Actinopteria communis £[.
40 A. iuBignis C
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66
NEW YORK STATE MUSEUM
41 Goniophora sp
42 Megambonia crenistriata C...
43 Cypricardinia lamellosa Conrad
44 Conocardium inceptum H. (?) . .
45 Oriskania sinuata C.
46 Ciyptonella (?) fausta C
47 0. sp. nov
48 Rensselaeria ovoides Eaton . . .
49 Megalanteris ovalis 11
50 Eatonia medialis Van
5 1 E. peculiaris Conrad
52 Cainarotoechia barrandii H.. . . .
53 C. fitcliana //.(?)
54 C. oblata //.
55 C dryope Billings
56 Q.sp%
57 Anastrophia sp
58 Coelospira concava H.
59 C. dichotoina H.
60 Leptocoelia flabellites Conrad . .
61 Trematospira multistriata H. , .
62 Meristella lentiforiuis C
63 M. lata H.
64 M. (?) vascularia C
65 Spirifer arenosus Conrad
66 S. murchisoni Castelnau
67 S. saffordi H
68 Metaplasia pyxidata H
69 Cyrtina varia C
70 Ohonetes hudsonica C.
71 Chonostrophia complanata H. . .
72 Anoplia micleata H
73 Orthothetes becraftensis C. . ..
74 Hipparionyx pr.tximus Vanux. .
75 Stropheodonta lincklaeni IL. . .
76 Leptostrophia magnifica H.....
77 L. oriskania C.
78 Bracbyprion schuchertanum C.
79 B. iiiajus C.
80 Leptaena rhomboidalis Wilch..
81 Dalmanella pereleaans H.
82 Rbipidomella oblata H.
1
— 1 w
X X
4
X X
X
«8
OS
X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X
OS
t
Is
at
X X
X X X X
X
X
X X
X X
X X X
ORISKANY FAUNA OF BECRAFT MOUKTAIN
67
83 Crania pulchella H. & C
84 C. cf. bella Billings
85 Pholidops terminalis H
86 P. sp
87 Lingula cf. rectilatera H.
88 Rhombipora rhombifera H.
89 Stictopora ap
90 Unitrypa lata H
91 U. acclivis H
92 Lichenalia cf. crassa H.
93 Polypora separata -ff. (?)
94 P. »?>
95 Polyporella cf. compressa II.
96 Fenestella biseriata II. (?)
97 Heiiiitrypa columellata II.
98 Isotry pa sp.
99 Reteporina sp
100 Edriocrinus becraftensis C
101 Zaphrentis
102 Ptycbonema helderbergiae II. (?) . .
103 Vermipora streptocoelia 0
104 V. serpuloides II. var
105 Cladopora sniicra C
106 C. styphelia C
107 Aulopora cf. schoharie II
108 Monotrypella arbusculus H. (& S.. .
109 Hederella magna H. <& S
110 H. aracbnoidea C.
111 H. ramea C.
112 H. graciliora C
113 Dictyoneina cf. splendens Billvngs.
Total
r. 3 1
Hill
<u E OS r:
^ 4) O d o
X X
X X
X
X
25
X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X
113
s 2
24
X X
X X
10
With our present knowledge there are thus 113 recognizable, dis- tinct specific forms in the fauna of the Oriskany at Becraft mountain, and of these 94 are identifiable with species already known or are clearly new forms peculiar to the fauna. Of the 94, 25 preceded the
68 NEW YORK STATE MUSEUM
introduction of Oriskany sedimentation, having been first described from the fauna of the Helderbergian. In the arenaceous beds of the Oris- kany 23 occur; 10 range upward into the faunas of the Upper Hel- derberg (Ulsterian), but a part of these are restricted to the sandy, lower beds of this formation (Schoharie grit), and others have been noted only in the chert beds of Ontario, Canada, where the intermixture of Oriskany and Onondaga species is well marked and has been re- corded by Schuchert. The fauna contains 35 species which so far as known are peculiar to it. On farther analysis of the foregoing table, it is evident in some cases that species which range down and upward are restricted to particular groups. Thus the alien trilobites are from the Helderbergian ; the gastropods are exclusively Oriskany ; while the alien lamellibranchs are mostly Helderbergian. But the leading factor of the fauna, the brachiopod, has its derivation as freely from below as in the Oriskany invasion.
FAUNAL VALUES OF THE SPECIES
The following is a statement of the faunal values of these species or their closest affiliations with species of other faunas.
Dalmanites (Synphorla) stemmatus C. — D. (Syn.) Maecurna C, Maecuru sandstone,
Amazonas " var. convergens C.
D. pliacoptyx H. & O. — idem, Onondaga limestone, Ontario D. bii^ignatus C. — D. dentatus Barrett, Helderbergian, Port Jervis
D. pleuroptjx Conrad, Helderbergian and Ulsterian, N, Y. Phacops correlator C. — Ph. anceps C, Onondaga limestone, Ontario
Ph. braziliensis (7., Maecuru sandstone, Amazonas Ph. logani H. — idem, Helderbergian, N. Y.
Cordania becraftensis G. — Cord, cjclurus H. «fe C, Helderbergian, N. Y. Cord, hudsonica C.
Cj'phaspis minuscula H. — idem, Ulsterian, N. Y. Proetus conradi II. — idem, Schoharie grit, N. Y. Acidaspis tubereulata Conrad — idem, Helderbergian, N. Y. Lichas cf. pustulosus H. — idem, Helderbergian, N. Y. Homalonotus sp. Autodetus beecheri C.
ORISKANY FAUNA OF BECKAFT MOUNTAIN 6,9
Spirorbis assimilis C.
Comulites cingulatus J7.— idem, Helderbergian, N. Y.
Tentaeulites elongatus ^.— idem, Helderbergian, N. T.
T. (?) acus C.
Bellerophon sp.
Cyrtolites expansus ZT.— idem, arenaceous Oriskany, N. Y. and Pa.
Pleurotomaria sp.
Diaphorostoma desmaUim C. — D. ventricosum Conrad, arenaceous Oriskany, N. Y.
D. ventricosum Conrad — -idem, arenaceous Oriskany, N. Y. Strophostylus expansus Conrad — idem, Oriskany, Md. Orthonychia tortuosa H. — idem, arenaceous Oriskany, N. Y. Platyceras cf. gebhardi H. — idem, Oriskany, Md.
P. nodosuiii Conrad — idem, arenaceous Oriskany, N. Y.
Pterinea ? — Megambonia lamellosa II., arenaceous Oriskany, N. Y.
Pterinopecten subequilatera H. — idem, Helderbergian, N. Y.
Pterinopecten proteus C.
Pt. siguatus C. — Pt. terminalis H., Ulsterian, N. Y.
Pt. bellulus II., Helderbergian, N. Y. Pt. pumilus C. — Vertumnia, Mesodevonic Aviculopecten sp. Lyriopecten sp.
Actinopteria communis H. — idem and A. textilis H., Helderbergian, N. Y. A. insignis G. — A. communis II., Helderbergian, N. Y. Goniophora sp. Megambonia crenistriata C. — M. bellistriata H., Helderbergian, N. Y.
M. cardiiformis II., Onondaga limestone, N. Y. Cypricardinia indenta Conrad — idem, Onondaga limestone and Hamilton, N. Y.
C. lamellosa H., Helderbej'gian, N. Y. Conocardium inceptum K. — idem, Helderbergian, N. Y. Oriskania sinuata C. — O. navicella R. & C, Oriskany, N. Y. Cryptonella fausta C. — idem (?), Helderbergian, N. Y. Kensselaeria ovoides Eaton — idem, arenaceous Oriskany, N. Y. and Md. Megalanteris ovalis ^.— idem, arenaceous Oriskany, N. Y. Eatonia medialis Van. — idem, Helderbergian, N. Y.
E. peculiaris Conrad — idem, Helderbergian and arenaceous Oriskany, N. Y. Camarotoechia barrandii H. — idem, arenaceous Oriskany, N. Y.
C. litcliana 11. (?)— idem, arenaceous Oriskany, N. Y. 0. oblata H. — idem, arenaceous Oriskany, N. Y.
70 NEW YORK STATE MUSEUM
C. dryope Bill. — idem, Gasp^ limestone no. 8 C. sp.
Anastrophia sp.
Coelospira concava H. — idem, Helderbergian, N. Y. C. dichotoma H. — idem, arenaceous Oriskany
Leptocoelia flabellites Conrad — idem, arenaceous Oristany, N. T., Gasp6 (lime- stone no. 8 and sandstone), Brazil, Falkland islands, 8. Africa Trematospira multistriata H. — idem, Helderbergian, N. Y. Meristella lentiformis G. — M. lenta H., Oriskany, Ontario M. lata H. — idem, arenaceous Oriskany, N. Y. M (?) vascularia C.
Spirifer arenosus Conrad — idem, arenaceous Oriskany, N. Y. and Md. S. murchisoni Castelnau — idem, arenaceous Oriskany, N. Y. S. saffordi H. — idem, Helderbergian, N. Y. and Tenn. Metaplasia pyxidata II. — idem, arenaceous Oriskany, N. Y.; Onondaga limestone,
Ontario Cyrtina varia C. — C. rostrata, arenaceous Oriskany, N. Y.
C. dalmani, Helderbergian, N. Y. Chonetes hudsonica C. — idem Helderbergian, N. Y. (?), Gasp^ sandstone Chonostropliia complanata II. — idem, arenaceous Oriskany, N. Y.
Ch. lielderbergia H. & C, Helderbergian, N. Y. Anoplia nucleata H. — idem, arenaceous Oriskany, N. Y., Edmund's hill, Aroos- took CO. Me.
Orthothetes becraftensis (J. sp. indes. Gaspe sandstone
Hipparionyx proximus Van. — idem, arenaceous Oriskany, N. Y., Gaspe limestone
no. 8 Stropheodonta lincklaeni II. — idem, Oriskany, N. Y. Leptostrophia oriskania — L. becki IL, Helderbergian, N. Y.
L. perplana Conrad, Upper Helderberg and Hamil- ton, N. Y. L. magnifica H. — idem, arenaceous Oriskany, N. Y. Brachyprion schuchertanum C. — B. aratum II., Helderbergian, N. Y.
Stropbeodonta demissa Conrad, Hamilton B. majus 0. — B. varistriatum Conrad, Helderbergian, N. Y. Leptaena rhomboidalis Wilck. — idem, Helderbergian and Ulsterian, N. Y. Dalmanella perelegans U. — idem, Helderbergian, N. Y.
D. subcarinata H. — Helderbergian, N. Y.
►
ORISKANY FAUNA OF BECEAFT MOUNTAIN 71
Khipidomella oblata iZ— idem, Helderbergian, N. Y.
Crania pulchella E. dc (7.— idem, Helderbergian, N. Y.
C. cf. bella Bill. — idem, Gasp^ limestone no. 5.
Pholidops terminalis ^.— idem, ? Oriskany, Md. N. Y.
Ph. 8j>1
Lingula cf. rectilatera U. — idem, Helderbergian, N. Y.
Khombipora rhonibifera H. — idem, Helderbergian, N. Y.
Stictopora sj>.
Unitrypa lata H. — idem, Onondaga limestone, Ontario
U. acclivis //. — idem, Onondaga limestone, Ontario
Lichenaiia cf. crassa II. — idem, Helderbergian, N. Y.
Polypora separata //. (?) — idem, Onondaga limestone, Ontario
Poljpora
Poljpora cf. compressa H. — idem, Helderbergian, N. Y.
Fenestella biseriata II. (?) — idem, Onondaga limestone, Ontario
Hemitrj'pa columellata H. — idem, Onondaga limestone, Ontario
Isotrjpa
Reteporina
Edriocrinus becraftensis C. — E. sacciilus II., Oriskany, Md
Ptychonema helderbergiae H. (?). — idem, Helderbergian, N. Y.
Vermipora streptocoelia C.
Vermipora serpuloides H. var idem, Helderbergian, N. Y.
Cladopora smicra C. — idem, Onondaga limestone, N. Y.
(J. styphelia C.
Aulopora cf. schoharie II. — idem, Helderbergian, N. Y.
Monotrypella arbusculus H. db S. — idem, Helderbergian, N. Y.
Hederella magna II. — idem, Hamilton shales, N. Y.
H. arachnoides C.
H. ramea C.
H. gracilior C.
"We may briefly summarize this tabulation as follows. Of tbe 94 clearly defined species of this fauna, 38 represent expressions of species which began their existence in Helderbergian times ; on the other hand, but 18 of the species of the fauna continued their existence or appear to be represented by closely allied forms beyond the close of the Oriskany sedimentation. 29 are represented in the earlier known fauna of the arenaceous beds of the Oriskany.
72 NEW YORK STATE MUSEUM
Chapter 3
NATURE AND DISTRIBUTION OF THE ORISKANY FAUNA
IN NEW YORK
The fauna of the calcareous Oriskany is in no sense a mixed assemblage, or an intermingling of faunas of adjacent provinces. The sequence of life has continued without apparent interruption from the Helderbergian (Kingston beds) into the sediments of the Oriskany and the Onondaga limestone.
It is extremely probable that important variations from the fauna of the Catskill shaly (New Scotland) limestone had already made their appearance in the Becraft limestone, and that we first become acquainted with some of these in the study of the calcareous Oriskany. No proof therefore could be adduced more emphatically confirmatory of the intimate faunal relations of the Helderbergian with the Oriskany fauna and its successors than the facts brought forward in this paper.
The fauna discussed in the foregoing pages is that of the col- careous fades of the Oriskany formation. The sedimentary deposits of this and neighboring sections were essentially limestones notwithstanding the silicious content, whether diffused through the mass or segregated as cherty secondary product. In the earlier presentation of this fauna it was regarded as of lower Oriskany horizon, on account of the presence of many Helderbergian species, but we believe it will be more correctly construed as the representative of the proper and normal Oriskany fauna, the true fauna of this time unit inclosed in the sediments of its proper habitat.
distribution of the calcareous FACIES of the oriskany in new YORK
Ulster county. A complete section of the strata from the Coeymans limestone through to the summit or almost to the summit of the Oriskany
OEISKANT FAUNA OF BECRAFl' MOUNTAIN
73
formation, is exposed near Kingston, along the West Shore railroad one half mile southeast of Kondout creek.'
On the Becraft limestone, which is 60 feet thick, lies a very considerable thickness (222 feet) of impure schistose limestones, the "upper shaly" limestone of W. M. Davis, and the Kitignton beds of this paper. In the reported section these beds have been subdivided with eveiy variation in the sediment, which is in places a compact blue limestone carrying silicious matter, in others a gray, shaly and argilla- ceous limestone. The fossils of all its layers are those of the true New Scotland limestone faunas, the contents of the higher layers varying little from those of the lower.
I have identified the following species. (In making this section Mr Van Ingen and Dr Ruedemann divided these beds into 18 subdivisions, numbered from lowest to highest, 4-21. These minor divisions were based solely on slight changes in the character of the sediment. In the list of fossils I quote these subdivisions by number in order to show the range of the species.)
Dalmanites pleuroptyx, 4, 12, 21
Phacops logani, 12, 15, 16, 19, 21
Hoiiialonotus vanuxemi, 8, 9, 12, 19
Acidaspis tubcrculata, 12, 16
Tentaculites elongatus, 16, 19, 21
Cypricardinia lamellosa, 16
Camarotoeehia cf. campbellana, 4
C. mutabilis, 8
Eatonia peculiaris, 4, 6, 14
E. medialis, 9, 19
Spirifer cycloptenis, 4, 5, 12
S. perlamellosns, 4, 5
S. modestus, 12, 16
Coelospira concava, 4, 20, 21
Atrypa reticularis, 4 Meristella cf. laevis, 4, 5 Leptaena rhomboidalis, 4, 6 Stropheodonta becki, 4, 20, 21 Strophonella punctulifera, 4 Rhipidomella oblata, 4, 5, 6, 21 Dalmanella suboarinata, 5, 9 D. planoconvexa, 12, 14, 15 Pholidops ovata, 16, 19, 20, 21 Zapbrentis roemeri, 5 Duncanella rudis, 9, 12, 14, 16, 20 Pleurodictyum lenticulare, 9, 21 Hindia fibrosa, 6
'For the detailed succession here I have largely relied on observations made at my request by Mr Gilbert Van Ingen, who, aided by Dr Rudolf Ruedemann, has carefully collected from all the strata.
74
NEW YORK STATE MUSEUM
Immediately above these beds appear 11 feet, 3 inches of chert beds, followed by 18 feet, 7 inches of a fine quartz pebble conglom- erate (=29 feet, 10 inches). Then comes in a silicious and quite fossil- iferous limestone 5 feet, 6 inches in thickness (no. 29 of the section) and over it about 36 feet of chert bands containing a few fossils. The entire thickness of the deposits from the top of the Kingston beds to the base of the Esopus shale is about 60 feet.
The fauna of this part of the section is essentially contained in the calcareous layer, and is the following:
Dalmanites cf. stemmatus Phacops logani Proetus conradi Tentaculites elongatus Diaphorostoma ventricosum D. desmatum Cyrtolites sp.% Platyceras tortuosum Cryptonella fausta Megalanteris ovalis Camarotoecliia pliopleura
Camarotoechia barrandii Eatonia peculiaris Meristella lentiformis Spirifer murchisoni Leptocoelia flabellites Chonetes hudsonica Chonostrophia complanata Leptostrophia oriskaijia Edriocrinus sacculus Cladopora smicra
All of these species with the exception of Edriocrinus sac- culus are observed in the Becraf t mountain Oriskany fauna. No species occur in the chert bands which are not represented here.
At Gknerie, 7 miles north of Kingston, the same calcareous beds of the Oriskany are finely fossiliferous, probably affording a more complete representation of this fauna. The following are among the species identified :
Dalmanites cf. stemmatus Phacops logani Tentaculites elongatus Diaphorostoma ventricosum D. desmatum Cyrtolites sp. n. Platyceras gebhardi P. reflexum
Meristella lentiformis
Spirifer arenosus
S. murchisoni
Trematospira sj). n.
Anoplia nucleata
Leptaena rhomboid alls, va/r. ventricoBa
Leptostrophia magniiica
L. oriskania
ORISKANY FAUNA OF BECKAFT MOUNTAIN 75
Oriskania sinuata Orthothetes becraftensis
Megalanteris ovalis O. large sj). n.
Camarotoechia oblata' Brachyprion scliuchertanum
C pliopleura Hipparionyx proximus
Leptocoslia flabellites Cbonetes hudsoniea
Coelospira dichotoma Edriocrinus sacculus Meri Stella lata
This association has some peculiarities, e.g. the presence of some of the Cumberland Md., species which have not before been observed in the Oriskany of New York (Platyceras gebhardi and P . r e f 1 e X u m) and several forms of novel aspect.
Orange county. In the southern extension of these beds a similar faima accompanies the calcareous strata. In Orange county true silicious sandstones are absent but the pebble beds and cherts are well defined. These features have been clearly brought out by the work of Dr Heinrich Ries in his special report on the geology of this county, published in the IStli annual report of the New Yorh state geologist, 1898, p. 402, 483, etc. He says:
The two belts of Oriskany which occur in this county present widely different characters. The western belt forms the western part of the Ilelderberg ridge, which extends up the Neversink valley from Port Jervis. It consists of fine-grained, shaly sandstones and impure limestones, the latter often containing many fossils. The limestones weather to a soft, red rock, from which the fossils may often be dug with a knife. The beds dip to the westward under the Esopus slates and Pleistocene deposits of the Neversink valley, but the bedding is almost everj'where obscured and there is present a pronounced cleavage which causes the rock to split into very thin la3'ers. The cleavage generally dips steeply to the east. There are also present cherty bands containing fossils. The Oriskany forms narrow ridges and the thick- ness of the formation is about 125 feet [in the vicinity of Port Jervis].
The second Oriskany area is along the western side of Bellvale and Skunnemunk mountains, where it affords a fine-gi"ained red or gray quartzite which changes locally into a conglomerate.
Fossils occur very sparingly In the silicious beds of the western area, Ries recording there Anoplia nucleata, Leptocoelia flabellites and Leptaena rhomboidalis. But on the west-
76
NEW YORK STATE MTJSEUM
em line of arenaceous limestones from Cuddebackville to Port Jervis the species are those characteristic of these calcareous beds in the localities already considered, to wit (Ries) :
Platyostoma depressum Tentaculites elongatus Orbiculoidea grandis Chonostrophia complanata Spirifer murchisoni
Meristella lata Leptocoelia flabellites Coelospira dichotoma Eatonia peculiaris Edriocrinus sacculus
The difference in the lithologic character of these beds on the eastei'n and the western flanks of the eroded Appalachian ridge is striking and may be construed as evincing the nearer approach of the easterly silicious and pebbly beds to the ancient shore line.
At Port Jervis the sections exposed at the Nearpass, Buckley and Bennett quarries have been given by Dr S. T. Barrett.' Here are 150 feet of the upper shaly (Kingston) beds lying above the Becraft lime- stone, and these are followed by the calcareous strata (5-10 feet) termed by Mather and Horton the Trilobite beds, which are specially characterized by the presence of Dalmanites dentatus Barrett.
Dr Barrett gives the following species as occurring in this stratum:
Horaalonotus vanuxemi Dalmanites pleuroptjx D. iiasutus D. deutatus [D. dolphi] Hyolithes centennialis Tentaculites elongatus Holopea antiqua Loxonema fitchana Pterin ea textilis Leptaena rhomboidalis Strophonella conradi Stropheodonta planulata
Strophonella cavumbona S. leaven worthana Stropheodonta becki Braehjprion varistriatum Chonostrophia complanata Eensselaeria mutabilis Orthis subcarinata O. multistriata Spirifer murchisoni Cjrtina rostrata Orbiculoidea discus O. conradi Schizocrania (?) superincreta
' Amer. jour. sci. 1877. 13 : 386.
OEISKANY FAUNA OF BECUAFT MOUNTAIN 77
T have not had opportunity to verify all of these identifications, biit the list as it stands shows a predominance of Helderbergian species. In fact, its Oriskany representation seems to me largely dependent on the identity of the specimens here regarded as Spirifer a r rectus (= S. murchisoni). I am satisfied that the Chonostrophia is the form (C. helderbergiae) of the New Scotland beds, and at all events the character of the rock shows the fossils to be an ag- gloraerated mass of remains brought together by wave wash. Present evidence indicates that this is not an Oriskany nor indeed a transition fauna but a proper part of the Kingston limestone beds.
Albany and Schoharie counties. To the north and west of the Kingston sections, through the Helderberg mountains the Oriskany f(»rmation becomes thinner and gradually loses its calcareous character. On the Oniskethau creek near Clarksville it is represented by a foot or tM'^o of dark compact chert. It is a gray, quartzitic sandstone about two feet thick at Countryman hill, near New Salem. At the top of the hill south of the Indian Ladder it has much the same character and thickness and abounds in Spirifer arenosus, Sp. murchi- soni, Meristella lata, etc. South of High point, near Alta- mont, the rock becomes slightly calcareous.
At Knox it is finely exposed as a compact quartz sandstone though not more than 2 to 3 feet thick.
On West mountain, Schoharie, at the house of George Acker (Murphy farm), above the Becraft limestone rest about 10 feet of a gray, schistose, arenaceous limestone, which terminates above in a hard quartzite. The calcareous content of the rock is considerably less than the silicious. Fossils are abundant :
Rensselaeria ovoides Spirifer murchisoni
Stroplieodonta magniventra Pholidops terminalis
Spirifer arenosus Meristella lata, etc.
In none of these sections can the Oriskany strata be properly termed sandstone, in the sense in which that term was originally applied to it in 1837.
78 NEW YORK STATE MUSEUJI
THE ORIGINAL ORISKANY SANDSTONE
The name Oriskany sandstone was applied by Vanuxem to white or yellowish, often friable and crumbling quartz sandstone exposed at Oriskany Falls, Oneida co., where it has a thickness of 20 feet. All calcareous beds are here wanting and the transition from the un- derlying Manlius limestone is abrupt, but fossils are found in abund- ance though not in great variety, the species being for the most part, Spirifer arenosus, S. murchisoni, Eensselaeria ovoides, Hipparionyx proximus, Chonostrophia complanata and Meristella lata. This quality of rock does not occur in any of the eastward exposures of the Oriskany from Albany county to the New Jer- sey line except as an occasional thin streak without fossils. From Oriskany Falls westward no calcareous beds appear except toward the top of the deposit as the sedimentation grades into that of the Onondaga limestone above. Through Onondaga county into Cayuga, the white, often granular, sandstone is frequently exposed, perhaps nowhere better than at its extreme western appearance at Yawger's woods just north of Union Springs. Vanuxem observed that at no other outcrop of this sandstone are the fossils so finely preserved.
The character of the Oriskany deposit in New York from Schoharie county westward may be regarded in a general way as a series of arena- ceous lenses (in strike section) connected by thin sheets of quartzitic sandstone. The outcrops at Oriskany Falls and Yawger's woods are such lenticular masses. Others occur in the sections at Jamesville and Skaneateles Falls and the last that is well marked in the westernmost extension of the formation occurs at Phelps, Ontario co. Between that point and Buffalo the rock may be traced as an undulated sheet a few inches thick composed of angular pieces of the underlying water- lime cemented by dark quartz sand.
At the horizon of the formation in the deep salt shaft put down at Livonia, Livingston co., was a 4^ foot layer at a depth of 1000 feet. This layer was a hard, compact quartz sand, almost a quartzite, which in its lower part contained frag- ments of the hydraulic limestone on which it rests, cemented
ORISKANY FAUNA OF BECK AFT MOUNTAIN 79
together in the mass. The few traces of fossils in this rock indicated for the most part Ulsterian species, Pentagonia unisulcata, Pentamerella allied to P . a r a t a , but also a Spirifer, prob- ably S. arenosus. In the Buffalo cement co.'s quarries at Buffalo, the Oriskany sandstone is found to lie in small masses which have been M^ashed into the cavities of the corroded surface of the Manilas waterlimes and in vertical fissures filled with white quartz sand which traverse the Manlius limestone and the Eurypterus-bearing cement beds beneath. Fuller reference to this occurrence is made on a subsequent page.
This variation in thickness in different meridional sections results in what appears at present an actual absence of the formation from the rock series in certain places. It has thus not been detected in the region about Cedarville, Herkimer co. Again it makes an abrupt appearance at Splitrock near Syracuse. In Seneca county it does not manifest itself at all, but turns up in Ontario county at the village of Phelps, as just noted. Other evidences of this interrupted depo- sition occur between Ontario county and Lake Erie.
Such discontinuity of the sand deposits of the Oriskany are indi- cations of an exposed and broken coast line, in the western part of the state, the sand feebly encroaching on areas of entirely different deposition.
The great brachiopods, Spirifer arenosus, Rensselaeria ovoides, Hipparionyx proximus and Meristella lata with Tentaculites elongatus, which are the species goner ally present in these arenaceous lenses, could not have had their habitat on such a deposit and in a sea whose depth favored such deposi- tion. W^e shall not be wrong in regarding these accumulations of remains in the true Oriskany sandstone as agglomerations, swept out of their facies and away from the more calcareous, deeper water deposits of the time. To regai'd them as species of the sandy facies of Oriskany time would, I believe, be altogether erroneous. They appertain truly to the calcareous facies and the normal fauna of the Oriskany formation.
80 NEW YORK STATE MUSEUM
FAUNA OF THE GASPE LIMESTONES
In connection with this Oriskany fauna that of the limestones of the Gaspe peninsula, province of Quebec, requires brief consideration. This remarkable series of 2000 feet of limestones was first exploited by Sir William Logan in 1844^ who separated them into eight divisions*, num- bering from bottom to top. The organic contents of the entire series are principally known from the description of the species by Billings*. This author however makes no reference to the considerable number of forms mentioned by Logan in his characterization of his subdivisions of the group. The record of species has been somewhat augmented in recent years by the lists given by Ells in his report on the geology of the Gaspe peninsula, the new identifications of which are largely ascribed to Dr H. M. Ami. This entire series of limestones was origi- nally regarded of Siluric age; Billings afterward demonstrated and Logan conceded the similarities between the fauna of division no. 8 and that of the Oriskany of New York, while Ells and Ami are not disposed to assign to the Siluric any other part than divisions 1 and 2. This great section of limestone deposits doubtless presents the most gradual of known transitions from beds (no. 1 and 2) carrying a fauna cor- relating with Helderbergian time and composition, through a great thick- ness of sparsely fossiliferous calcareous and magnesian beds (no. 8, 4, 5, 6) into a profuse limestone fauna with most pronounced Oriskany traits (no. 7 and 8). It is not practicable to here present faunal lists resulting from the writer's recent studies of the series though these would serve to indicate the close similarity of complexion in the lower beds, 1 and 2, and the beds at Stewart's cove, Dalhousie and in the Chapman plantation, Aroostook county, Maine. In the upper beds, no. 7 and 8, the fauna carries Rensselaeria ovoides, (a small and slender variety) Megalanteris ovalis, Hipparionyxproxi- mus, Dalnianites, very close to D. stemmatus, Stroj^heo- donta magniventra, Camarotoechia pliopleura, C.
*l8t annual report geol. sur. of Canada. "Geology of Canada. 1863 cb. 16. 'Geol. sur. Canada. 1874, vol. 2, pt 1.
0RI8KANY FAUNA OF BECBAFT MOUNTAIN 81
dryope, Eatonia peculiaris, Leptocoelia flabellites, etc., all of which pertain to the fauna of the calcareous Oriskany of New York. With these strong Oriskany traits the fauna canies certain species which indicate the continuance of a still earlier assemblage. Billings assigned to it some species of the Helderbergian and though the majority of these identifications re- quire careful reconsideration there is in the organic content of limestone no. 8 a notable constituent of Helderbergian origin. It is interesting to note that certain of the lower beds of division no. 8 specially at the exposure at Ship Head, Cape Gaspe, are com- posed of a greenish sandy limestone, extending through a thick- ness of not less than 150 feet. They evince thus, as do the Oriskany beds of eastern New York a considerable siliceous content though still to be regarded as calcareous deposits. Logan's subdivision of the limestone series was given with lucidity and exactitude but seems hardly to clothe this unique succession with the dignity and importance it merits. Dr Ami has suggested that the upper beds, 7 and 8, be termed the Grand Greve limestones, from the little village on the peninsula where these strata are best exposed and most readily accessible. To Mr Charles Schuchert and the writer, who have recently spent some time in this region, this name seems happily chosen and we have thought that with equal propriety the lower beds, 1 and 2, exposed in the base of Mt St Alban along the shore of Cape Rosier cove on the gulf of St Lawrence, may be called the St Alban limestones, while the passage beds of Billings (no. 3, 4, 5, 6) which are displayed in the fine 700 foot vertical escarpment at Cape Bon Ami, west of Cape Gaspe, may receive the name of Cape Bon Ami limestones.
Logan and Dawson in referring to the interesting outcrop of " Silu- rian " or " Lower Helderberg " rocks on the coast one half mile south of Dalhousie, N. B., speak of it as "Cape Bon Ami." I have also ob- served the locality thus given on specimens from there exhibited in the fine museum of McGill university. Lest confusion arise from the dupli- cation of this name, I may note that the little headland in question
82 NEW YORK STATE MUSEtJM
at Dalhousie is locally known as the "Bon Ami rocks." It is more- over, a mass of eruptive, the extremity of one of the parallel apophyses extending eastward from the great massive of Dalhousie mountain. The fossiliferous rocks are exposed for the most part in Stewart's cove, some distance south of this point.
Chapter 4
THE DEVONIC AGE OF THE HELDERBERGIAN FAUNA AND THE BASE OF THE DEVONIC SYSTEM IN NEW YORK
The fact of the presence of numerous Helderbergian species in the fauna of the Oriskany of Becraft mountain, as an integral part of that fauna, not a casual intermixture, is sufficient demonstration that the fauna of the Helderbergian became modified in its continued existence by the departure or extinction of certain of its species only. A fair percentage kept the field up to the time of and pending the incursion of species of the early Oriskany. In this way the former became a true and proper part of this new fauna with whose indicial species it coexisted throughout the remainder of its duration. A modification so gradual as to permit such an uninterrupted existence can not sever the close relation of the one fauna in its entirety to the other. It is therefore a natural corollary from the account given of the Oriskany fauna, to consider briefly the relation of the organic assemblage con- stituting the typical and normal Helderbergian to the Devonic type of organic life, and that formation in its relation to the Devonic system.
We may postulate this proposition: the sections on which the term. Lower Helderberg group, was based are in Albany and Schoharie coun- ties N. Y. ; it is here that the formation attains its greatest and most differentiated sedimentation as well as its highest profusion of organ- isms ; it is therefore to these sections and their organic contents that every argument in analysis and correlation of the fauna and its con- taining sediments must be eventually referred.
0RI8KAKY FAUNA OF BECRAFT MOUNTAnf 83
1 THE ARGUMENT FROM CORRELATION
Since the proposition of Beyrich in 1867 to correlate the Helder- bergian faunas of New York with strata in the Hartz mountains which he believed to be of lowest Devonic age, the most careful study of the lower Devonic has resulted in a like conclusion. Prob- ably the detailed investigations following Beyrich's suggestion, by that highly accomplished student of the Devonic, Prof. E. Kayser of Marburg, effected the widespread acceptance of this correlation of the Helderbergian with the lowest Devonic, specially among European students, with whom little question of its propriety and exactitude has found expression during the last decade. The history of the earlier stages of the dis- cussion concerning the age of these and other beds which had been at first regarded as of, upper Siluric age, was given by the writer with some fulness 10 years ago,* and has again been presented in a recent paper by Charles Schuchert. To these the reader is referred. It is not germane to the purpose of this paper to bring forward again the history of labors which have so far as evidence from correlation goes, firmly established the Devonic age of this fauna. To enumerate the names of those who have entered into this problem is to give the full tale of the most experienced students of these faunas, Kayser, Tschernyschew, Freeh, Barrois, Nov^k, Oehlert and others. It is, however, quite unnecessary to seek in extra-limital correlates the evidence of such Devonic age.
2 THE ARGUMENT FROM THE INTRINSIC CHARACTER OF THE FAUNA
With whatever emphasis extra-limital correlates bespeak the Devonic age of this fauna, the strongest demonstration of its Devonic affinities is intrinsic. In the work above cited the \vriter brought for- ward in a tentative way a summation of uuch evidence, and since that time has taken opportunity on several occasions to refer to the increas- ing and convincing evidence of the proposition. No American geolo- gist has since then given attention to the subject of the predominant
* 8th ann. rep't N. Y. state geologist. 1889. p. C2-91.
84 NEW YORK STATE MUSEUM
faunal traits of the Helderbergian, with the exception of Charles Schuchert, of Washington, who, after expressing his conviction of their Devonic character, resulting from protracted study of the brachiopods of the fauna' has entered into the subject in much detail and with great force.* George H. Girty has discussed the characters of the sponges and coelentrates of this fauna in a valuable paper published in the IMh annual report of the New Yoi'h state geologist, 1895, but mthout entering widely into the consideration of the faunal bearing of the species discussed. For the rest, stratigraphers, cartographers, writers of textbooks and others who have had no occasion to consider the subject on its merits and perhaps no adequate appreciation of the merits of the question, have till lately been content still to accept the view promulgated largely by the influence of Murchison, that the fauna constitutes a terminal member of the upper Siluric section in New York. No full analysis of the constituents of the typical Helderbergian fauna can be presented here, nor is it essential. A review of the species of the entire fauna with the incorporation of the very consid- erable number of undescribed forms known to occur in it would be necessary to set the matter forth with its full force. It will suffice here to restate briefly the leading features of the association which must be relied on to determine its age. Let this statement, however, pre- face the present discussion. 2he Helderbergian fauna is that contained by the strata, all and several, lying between the top of the Tentaculite (Manlius) limestone below, and the top of the Kiiigston beds above.
The Helderbergian fauna
Siluric characters
Positive elements
Trilobites. There are no features presented by the trilobites which indicate Siluric at^e.
Cephalopods. In the Helderbergian, representatives of the cephalo- pods are most rare. The species of the genera Orthoceras, and
"■See Bull. U.S. geol. sur. 1897. no. 87. 2 Bull. geol. see. America 1900. 11 : 241-332.
ORI8KANY FAUNA OF BECBAFT MOUNTAIK '85
Cyrtoceras are very imperfectly known. The little known species of Cyrtoceras are not diagnostic.
Pteropods. The species of Conularia and Tentaciilites present no diagnostic characters.
Gastropods. Holopea, Diaphorostoma, Strophostylus are diffused throughout Siluric and Devonic horizons. Of all these genera Holopea alone is near its Siluric culmination.
Lamellibranchs. Cypricardinia is freely represented in the Niagaran, but its culmination is of Devonic age. Actiuopteria occurs occasionally in the Niagaran, but its paucity there is in marked contrast to its abundance in the Helderbergian. There are no indub- itably predevonic types in this element of the fauna.
JBracliiopods. The only species of this extensive group known to be common to the Helderbergian and Niagaran faunas are the cosmo- politan brachiopods, Leptaena rhomboidalis and A t r y p a reticularis. The prevalence of species of Dalmanella is sug- gestive of Siluric affinities. The genus is typically expressed in the species D. elegantula and D. arcuaria of the Niagaran, but attains its culmination in the Helderbergian. (I), planoconvex a, D. per- elegans, D. concinna, D. quadrans). In successive faunas this means no more than the progressive development of a generic group. In time subsequent to the Heldei'bergian the genus is continued to the close of the Devonic.
Bilobites varica is foreshadowed in the B. b i 1 o b a and B. acutiloba of the Niagaran. The genus is not of subsequent date.
Orthostrophia (O. strophomenoides and O. H a 1 1 i ) rep- resents a short-lived genus, doubtfully anticipated by the Or this fasciata of the Niagaran.
Scenidium is a genus which appeared in the Trenton, attained its maximum in the Niagaran, declined and disappeared in American faunas with the Sc. insigne of the Helderbergian. In Europe the genus continued into the middle Devonic (Sc. areola Kays.).
Of the genus S p i r i f e r the species S. m a c r o p 1 e u r a Con. is a final expression of a group (liadiati pauciplicati H. ifeC. ) which culminated in the Niagaran.
86 NEW YORK STATE MUSEUM
Anastrophia, the upper Siluric representative of the earlier Parastrophia, is represented in the Helderbergian, but it was also present in the calcareous Oriskany,
Sieberella attains its highest development in the Siluric and its species (S. galeata and S. pseudogaleata) are of frequent occurrence in the Helderbergian. The type, however, does not end here, but is continued upward into the Mesodevonic, even the species S . galeata being commonly identified from these horizons by European writers.
Bryozoans. But few Siluric affinities are expressed in this group. Rhinidictya presents its latest species. Diamesopora and C a 1 - 1 o p o r a range from lower Siluric upward into the Onondaga limestone.
Grinoids. None of the crinoids are of distinctively Siluric char- acter.
Cyatids. The presence of Anomalocystites (though this genus occurs in the Oriskany), Lepadocrinus, Sphaerocystites, is suggestive of wfsiing Siluric traits. The cystids are not absent from succeeding faunas, but are of rare occurrence.
Corals. Duncanella rudis of the Helderbergian is anticipated by D. borealis of the Niagaran and succeeded by D. truncata of the Onondaga.
' Enterolasma (E. strictum) is the last representative of a genus which makes its other appearance in the Niagaran.
Grojptolites. Girty has described Monograptus beecheri from the Helderbergian. Before this interesting discovery we had no knowl- edge of the continuation of the rhabdophorous graptolites beyond the Niagaran fauna except in the case of Dictyonema, which is not uncommon in the Mesodevonic. There are several structural features, indicated by Mr Girty's description and figure, which indicate that M. beecheri will not prove a representative of the Monograptus type of the Siluric, Freeh has expressed the view that such forms are probably Re-tiolites.
Negative elements
The absence of the Devonic types, Cryphacus and Goniatites, is noteworthy.
OEISKANY FAUNA OF BECRAFT MOUNTAIN'
87
Devonic cliaracters
Positive elements
Trilolites. This element is, for the purposes of a diagnosis, of the first importance. The trilobitic genera present are Homalonotus, Bronte us, Dalmanites, Phacops, Acidaspis, Lichas, Pro- etus, Cordania and Cyphaspis.
The single species of Homalonotus (H. vanuxemi) possesses the strongly annulated pygidium characterizing the earlier representatives of the genus (e. g. H. delphinocephalus of the Niagaran, H. major of the Oriskany) and in this respect is in strong contrast to the latest members of the genus, with obsolete pygidial ribs. On the other hand, the species presents the smooth, unlobed glabella of the prevalent H. dekayi of the Hamilton, and therein indicates a pro- gress from the Siluric type of Triraerus to the Devonic Dipleurae.
Bronteus barrandii is a species with comparatively small pygidium, having a simple, unbifurcated median rib; representing a group prevailing in the lower Devonic faunas of Europe.
Dalmanites. The typical expression and phyletic normal of this genus (Odontochile) is represented by a series of Siluric and Devonic forms in which the glabellar lobation is without coalescence and the pygidium more or less caudate. Tliis type is foreshadowed in the lower Siluric (D. achates Billings), and the Niagaran species, D. limulurus, D. vigilans and D. verrucosus, express the struc- ture without modification. The outburst of dermal extravagances which characterizes many Devonic trilobitic genera is foreshadowed in this group in the snouted D. bicornis of the Niagaran, a tendency per- petuated and carried to extreme in D. t r i d e n s and D. n a s u t u s of the Helderbergian. A diiferent style of ornament is evinced in D. pleurotopyx of the Helderbergian (a species which continued its existence into the Onondaga limestone). Here the frontal margin becomes crenulated, and this tendency is more highly elaborated in the D. d o 1 p h i and D. d e n t a t u s of the calcareous Oris- kany. This style of ornament associated with simple glabellar lobation disappeared with the disappearance of D. pleuroptyx in
88 NEW YOEK STATE MUSEUM
the Onondaga. In Cryphaeus of the Mesodevonic the lobation is retained, but the marginal ornament has disappeared from the cepha- lon and appears on the pygidium. The cephalic ornamentation in the species, D. stemmatus, Oriskany, D. regalis, and D. anchiops Schoharie grit, and D. selenurus, etc. of the Onondaga limestone is associated with lobal coalescence and may be looked on as an instance of morphic equivalence.
Phacops is represented by P. 1 o g a n i (P. hudsonicus). The species mentioned are typical Phacopes, forms in which the glabellar lobes are almost or quite coalesced, the glabella ventricose and the pygidium short. Such typical forms are not known in any earlier American fauna. In general this genus divides itself into two groups, in one of which the glabellar furrows are represented by faint, linear impressions, and the pleura of the pygidium are duplicate ; in the other the furrovvs are obsolete and the pygidial pleura simple. The latter is believed to be limited to Mesodevonic faunas (P. r a n a , Hamilton, P. latifrons, Eifelian), while the former is widely disseminated as a characteristic Paleodevonic group. To this belong the Helderbergian species.
Of Acidaspis we have two species ; A. t u b e r c u 1 a t a is re- lated to the Onondaga A. callicera. The remarkable A. h a m a t a (genus Dicranurus) with long, recurved cervical horns, finds its only known analogue and almost specific identity in the A. monstrosa, Barrande, of the etage G (Paleodevonic).
L i c h a s is represented by L. pustulosus, the most abundant species, which seems to indicate a type of subgeneric structure not elsewhere presented. L. consanguineus belongs to the subgenus A r g e s and has species both in the Siluric and Devonic.
The single species of Proetus (P. protuberans) in the Helderbergian of New York is of rare occurrence. In type of struc- ture it conforms throughout to the series P. conradi, Oriskany, P. angustifrons, Schoharie grit, P. c 1 a r u s , Onondaga limestone and P. r o w i of the Hamilton group.
Cordania makes its earliest appearance in the Helderbergian,
OBISKANT FAUNA OF BECBAFT MOUNTAIN 89
and is represented in the Oriskany, Schoharie grit, Onondaga and Hamilton faunas.
Cyphaspis coelebs ( the only species ) is closely allied to C. m i n 11 s c u 1 u s of the Oriskany and Onondaga.
Gastropods. This group is characterized by an immense develop- ment of the genus Platyceras, which has been but sparingly rep- resented in the Siluric faunas, but attains its numeric climax in species here and in the Onondaga and Hamilton. The prevalence of these forms is one of the most striking characters of " Hercynian " faunas, and Barrois has suggested that they may v?ith propriety be designated by the name Capulian. The type Orth onychia attains its culmina- tion in the Helderbergian and Ulsterian; the nodose species, w^hich become abundant in the Oriskanj' and Onondaga, are represented; while the lamellose species and the ventricose, platystomoid forms are predominant. The spinose group, prevailing in the Onondaga and Hamilton, has not been observed here.
The genera Strophostylus and Platystoma have both more abundant representation in earlier and later faunas, and are not diagnostic.
Lamellibranchs. The prolific development of pterinaeoids stands in sharp contrast to their comparative paucity in the Niagaran, while it is in harmony with their abundance in the Devonic. (Avicula textilis, A. communis, A. obliquata, A. manti- cula, A. securiformis, A. pauciradiata, etc.). A v i c u 1 o- p e c t e n has a well developed representation (A. tenuilamellata, A. spin 11 lifer a, A. schoharie, A. umbonata, A. bellula).
Mytilarcas of large size and gibbous form, belonging to the Devonic subgenus Plethomytilus, are abundant in individuals (M. ovata, M. cordiformis).
Conocardium has but a meager representation in the single, rare species, C inceptum. This genus is but sparingly known in Siluric faunas.
A large species of Modiomorpha (M. o b 1 o n g a) ; undescribed species of the genera Grammysia, Goniophora, Paracylas are also known.
90 NEW YORK STATE MUSEUM
£rac7iiopods. Rhipidomella, which culminates in the Meso- devonic, is largely represented. But a few doubtful representatives are known in the Silunc.
Schizophoria, eminently characteristic of the higher Devonic, is clearly defined in the Helderbergiun. The only earlier species of the genus is generically inchoate. Orthothetes is in the line of progress from its elementary forms in the Niagara to its abundant development in the middle and upper Devonic. It is represented by two species, O. deformis and O. woolworthana.
Leptostrophia, beginning its development here becomes a large and characteristic Devonic group.
Brachyprion, well advanced in structure toward the type of Stropheodonta, is represented by two species. Progress along the same line continues in the Oriskany and thereafter the type seems to lose itself in the latter genus.
Strophonella, starting in the Silunc, attains its culmination in the Helderbergian (S. headleyana H., S. leaven worthana H., etc., and gradually declines to the close of the Devonic.
Leptaenisca is not known elsewhere in American faunas.
Chonostrophia is known only in the Helderbergian, Oriskany and Onondaga.
Spirifer. The lamellose septati, represented by Sp. perlamel- 1 o s u s , become culminant in later Devonic faunas.
The same is true of the Fimbriati unicispinei, (S. saffordi, S. cyclopterus, S. octocostatus) which are preceded by an inceptive representation in the Niagara and followed by several species in the Devonic.
Of the Aperturati the only species is S. concinnus, the earliest representative of the S. orestes subtype. This entire group becomes culminant in the Devonic and lower Carbonic.
The genus Merista is known in America only in the Helder- bergian and Oriskany faunas.
Meristella has a remarkable development in this fauna and its existence is continued through the Mesodevonic. It is not known in the Siluric.
OKISKANY FAUNA OF BECRAFT MOUNTAIN 91
A similar outburst of species is afforded by the genus Tremato- s p i r a (T. multistriata, T. costata, T. perforata, T. sim- plex). The genus is here culminant, the small T. c a m u r a of the Niagara being the only preexisting species.
Parazyga is known only here and in the Mesodevonic.
Nucleospira is here near its culmination with a considerable subsequent development into the Mesodevonic.
Stenoschisma is not elsewhere known. '
Uncinulus attains its culmination here (U. rautabilis, U. abrupta, U. vellicata, U. nucleolata).
Eatonia is known only in the Helderbergian and Oriskany faunas.
Sieberella (S. galeatus and S. pseudogaleatus) occurs widespread in the upper Siluric, and a common middle and upper Devonic shell is referred by European paleontologists to S. galeatus.
Rensselaeria (R. mutabilis, R, aequiradiata, R. ellip- tica, etc.) makes its first appearance here and disappears with the close of the Oriskany.
Trigeria is known in America only in the Helderbergian (T. portlandica Square lake Me.) and Oriskany (T. gaudrp Oehlert, Cumberland Md.) faunas.
Cryptonella begins its existence in the Helderbergian (C. e x • i m i a ) and is continued into the lower Carbonic.
Bryozoans. The sum of the characters of this element points strongly toward the Devonic. Rhombipora, Diamesopora, Coelocaulis, Callotrypa, Fistulipora, Lichenalia, have a few representatives in the Siluric, but are here much progressed toward or to their culmination. Paleschara, Stictopora, Cra- nio p o r a , abound in later faunas. The feuestelloids ( F e n e s - tella, Unitrypa, Hemitrypa, Polypora) are relatively few in the Siluric, greatly abound in the Helderbergian, but attain their culmination in the Mesodevonic. The genus Thamniscus makes its first appearance here.
Crinoids. Edriocrinus occurs only here and in the Oriskany.
92 NEW YORK STATE MUSEUM
Mariacrinus, a subgeneric expression of Melocrinus, attains its culmination in this fauna. Coronocrinus, Cordylocrinus, Cara- arocrinus, Brachiocrinus and Aspidoc ri n u s are not known elsewhere.
Corals. The development of explanate Favositea is notable and in direct accord with their progress toward culmination in the Onondaga limestone.
Striatbpora and Aulopora attain their culmination in the Devonic.
Pleurodictyum here makes its first appearance.
Zaphrentis has a meager representation ( Z. r o e m e r i ) ; its culmination is in the Onondaga limestone. The same is true of Cladopora and Vermipora.
Of the stromatoporoids, Girty has described five species of Syringostroma, a genus not known in earlier faunas but occurr- ing in the middle Devonic.
Sponges. Hindiafibrosa, though occiirring in the Siluric, is here at its most profuse development, and its existence is carried upward into the Onondaga limestone (Onondaga county).
Negative elements
Trilohites. The Siluric genera Bumastus, Calymmene, S t a u roc e p h a 1 u s, Encrinurus, S p h aer e x o c h u s, Platy- notus, Crotalocephalus, are absent.
Cephalopods. The group is but very sparsely represented. There are no representatives of the genera Ascoceras, Actinoceras, Oncoceras, Hormoceras, Cyrtoceras (of Siluric type) Pentacoceras, Hexacoceras, or any charactez-istic Siluric types.
LamelUbranchs. Ambonychia, Anomalodonta, Telli- nomya, Clidophorus and Modiolopsis are wanting.
Brachiopods. The entire family of the Trimerellidae (Trimerella, Dinobolus, Monomerella, Rhinoboliis, Lin- gulops, Lingulasma), which was so profusely represented in the late Siluric, is absent.
Orthis (s. 8. ) disappears in the Niagaran j probably also, P 1 e c t •
ORISKANY FATTKA OF BECRAFT MOUNTAIN
98
orthis and Hebertella. The upper Siluric genera Mimulus and Streptis are absent.
Strophomena has not been perpetuated beyond the Siluric.
Plectambonites disappears in the Niagaran.
Of the genus Spirifer, we have no representative of the S . n o b i 1 i s type (Radiati duplicati).
The genera Whi t f iel d el 1 a, Hyattella, Dayia, Hindella, Meristina, Glassia, Zygospira are absent.
Ilhyn<jhotreta and Parastrophia disappear with the Niagaran.
Conchidium, Pentamerus, Barrandella and Strick- land i n i a are not present.
No terebratuloid genus is known in the upper Siluric.
Eichwaldia disappears with the Niagaran.
These genera of Crinoids disappear with the Niagaran fauna: Eucalyptocrinus, Glyptaster, Thy sanocrinus, Marsupio- crinus, Lyriocrinus, Lamp terocrinu s, L ecanocrinus, Pisocrinus, Allocrinus, Coccocrinus, D e nd rocrin u s, Ampheristocrinus. None of the following Niagaran genera of Cys- toids continiie beyond that fauna : Caryocrinus, Callocystites, Ly socy s tites, G o ra p h o c y s t i t es, Al 1 oc y s ti t e s, Halocys- tites, Hemicosmites, Apiocystites, Heterocystites.
This statement of the affinities of the various generic elements of the Helderbergian fauna is more graphically represented as below. The direction of the dashes indicates either (forward) Devonic or (backward) Siluric affinity.
Trilohites Dalmanites (Synphoria) — Lichas —
Phacops — Proetus —
-r-Homalonotus Cordania —
Bronteus — , Cyphaspis —
Acidaspis —
Cephalopods — Orthoceras — — Cyrtoceras —
94
NEW YORK STATE MUSEUM
— Tentaculites —
Platyceras — Orthonychia — — Strophostylus —
Actinopteria — Aviculopecten — Mytilarca — Conocardium — Modiomorpha —
— Dalmanella — Rhipidomella — Schizophori a —
— Bilobites
— Orthostrophia
— Scenidiura Orthothetes — Brachyprion — Leptostropbia — Strophonella — Christiania Leptaenisca Chonostrophia —
— Spirifer —
— Rhinidictya — Diamesapora — Callopora — Rhombipora — Coelocaulis — ' Callotrypa — Fistulipora — — Lichenalia
Pteropods Gastropods
Lamellibranchs
JBrachiopods
Bryozoa
— Conularia —
— Diaphorostoma— — Holopea
Cypricardinia — Graramysia — - Goniophora — Paracyclas —
Merista —
Meristella —
Trematospira —
Parazyga — -Nucleospira —
Stenoschisma
Lissopleura
Unciniilus
Eatonia — -Sieberella — -Anastrophia —
Eensselaeria —
Trigeria
Cryptonella —
Thamuiscus — Paleschara — Stictopora — Fenestella — Unitrypa — ■ Hemitrypa — Polypora —
|
OEISKANT |
FAUNA OF BECKAFT Grinoids |
MOUNTAIN |
|
Mariacrinus — |
Brachiocrinua |
|
|
Coronocrinus |
Aspidocrinus |
|
|
Cordylocrinus |
Cystoids |
|
|
■Anomalocysfcites — |
— Sphaerocystites |
|
|
-Lepadocrinus |
Corals |
|
|
Duncanella — • |
StriatojK)ra — |
|
|
-Enterolasma |
Pleurodictyum — |
|
|
Zaphrentis — ■ |
Cladopora — |
|
|
Favosites — • |
Verraipora — |
|
|
Aulopora — • |
||
|
' |
Graptolites |
|
|
-Dictyonema — |
Stromatoporoids |
— Monograptus ? |
|
Syringostroma — |
||
|
Hindia — |
Sponges |
95
i
3 THE ARGUMENT FROM STRATIGRAPHY
The fact that the faunas of the Manlius limestone and the Ron- dout waterlimes are not, in this discussion, considered a part of the fauna of the Helderbergian has already been stated. The distinctive differences in these faunas are briefly noted in the following chapter.
In eastern central New York there is no interruption in the stratigraphic succession from the Manlius limestone upward. The heavy layers of this formation are generally capped by a Stromatopora limestone. In the westward extension of the Helderbergian, the Coeymans and New Scotland limestones gradually lose their individu- ality. In the records of salt, gas and artesian wells throughout the district west of Cayuga lake the strata referred to the Lower Helder. berg, often of considerable thickness, present nothing of the true Helderbergian. These vague and indeterminate assignments cover for the most part the blue limestone, generally quite pure and often
96 • NEW YORK STATE MUSEUM
hydraulic, found between the base of the Onondaga or of the Oris- kany sandstone when present, and the Eondout waterlimes lying above the gypsum beds. These beds are the stratigraphic equivalent of the Tentaculite limestone, for they contain species which charac- terize this horizon in eastern New York, though Tentaculites itself is rarely seen in the western exposures.
At the quarries of the Buffalo cement co. at Buffalo, is a section of unusual interest to which brief reference has been made. Above the Rondout waterlimes the strata which bear the fauna of the Manlius limestone are continuous to the base of the Onondaga limestone.
The quarryraen divide this portion of the section into " cement rock " below and " bullhead " above, and, though the lower passes gradually into the upper, it is in the former (Rondout) that the species of eurypterid crustaceans prevail, while in the latter fossils are not com- mon, though the horizon is pretty well defined by an undescribed species of Cyathophyllum with representatives of Whitfieldella sulcata and Spirifer cf. vanuxemi (S, eriensis Grabau). This " bullhead " waterlime occupies the position of and is coextensive with the Manlius limestone and is the Manlius horizon. The upper surface of this deposit is extremely uneven, and seldom conforms with the approxi- mately parallel sedimentation lines of the rock itself. In parts of the quarry, where this surface has been exposed on a large scale by the stripping of the Onondaga limestone above, the contour is extremely irregular, and the depressions in some cases take on the aspect of crooked channels running into one another, the effect being just that which would result from the probable cause, erosion before the deposi- tion of the Onondasra limestone commenced.
The horizon of the Oriskany sandstone is indicated only by a thin seam of fine, bituminous matter, containing no sand except in a few of the depressions mentioned, where small characteristic nodules of black sand are found.
In certain parts of this section the upper hydraulic or " bullhead " strata show very positive evidence of disturbance and folding and at cer- tain places the crest of these folds is seen to be partially removed,
ORISKANY FAUNA OF BECEAFT MOUNTAIN 97
'while the Onondaga limestone beds lie horizontally on them. All these evidences are indicative of an interval of unrepresented time between the deposition of the Manlius limestone and the commencement of Onondaga sedimentation. These evidences are distinctly corroborated by the following accessory phenomena.
The same quarry shows several nearly vertical fissures which have been filled with white, compact quartz sand. The most clearly developed of the three such fissures here observed is shown in the accompanying plate and diagram. This is an irregular fissure transecting the strata nearly vertically, with horizontal apophyses running out along the sedi-
Onondaaa limesrone! ••bo II head*
5
— — — '- Top of cement roc/i
Floor of c^ua■^r^f
Diagram showing the largest of the sand dikes (A) In the quarries of the Buffalo cement CO., at Buffalo N. Y. The floor Of the quarry Is the lowest layer used for burning cement and while the dike seems to enter this stratum It does not penetrate It. The figure shows the Irregular character of the Assure walls, and the lateral apophyses In the lower part which are essentially parallel to the bedding. At the top Is a slight displacement of the " bull-head " or Manilas waterllme on one side of the dike. B shows a second dike, the filling of a very narrow fissure. Others are evident elsewhere In this quarry. The Onondaga limestone ties horizontally over them all and Is not penetrated by them.
mentation planes and across them at various angles. It is filled with firmly cemented quartz sand having the aspect and quality of typical Oriskany sandstone. The top of this fissure is in the Oriskany horizon and the overlying Onondaga limestones are undisturbed. It extends downward across the entire series of waterlimes to and perhaps below the base of the quarry. This disturbance and fracture of the strata, which has possibly been extended by solution and accompanied by a slight displacement on one side, must have taken place after the consolidation of the Manlius limestone and before the deposition of the undisturbed Onon-
98 NEW YORK STATE MUSEUM
daga limestone. This event belonged to the interval of the Helderbergian and Oriskany deposition elsewhere in New York, and the filling of the fissure is, doubtless, veritable Oriskany sediment.
We have already observed that at various localities throughout western and central New York the thin, cherty deposit of the Oriskany con- tains fragments of the hydraulic limestone from beneath. This con- dition was particularly noticeable in the remarkable section afforded by the salt shaft put down at Livonia, Livingston co. Such organic re- mains as occurred in this deposit were found entirely in the cement and were not well preserved, but showed indications of having been worn and broken by the waves. Evidence of this kind sufficiently demonstrates an interval between the Manlius and Onondaga limestones unrecorded in these sections, and shows the continuity of the rocks carrying the fauna of the former with the sedimentation immediately preceding and their discontinuity with the sedimentation of the true Helderbergian period.*
FAUNA OF THE MANLIUS LIMESTONE
The species of the so-called "Tentaculite limestone", so far as noticed, have been principally described in volume 3 of the Paleon- tology of New York, and the citations given in that work are of occurrences located mainly in the eastern and eastern-central parts of the state. Even where the limestone is in immediate contact with and conformable to the overlying deposits of the Helderbergian, there are few evidences of the continuation of any well established species above the " Tentaculite limestone " itself. In eastern-central New York a repetition of the Manlius fauna may appear after a brief preliminary invasion of the later and displacing fauna but in these oscillations be-
'After writing this account of the physical disturbances in the strata at Buffalo, based on observations made in 1899, I learned tiiat the phenomena had also been studied by Dr A. W. Grabau, who has published the result of his detailed investigations in a recent bulletin of the Geological society of America (2 : 347-76, 1900. Siluro-Devonic contact in Erie county, N.Y.) Grabau concludes that these fissures were formed by violent rupture of the waterlimes before the incoming of the sandy sediment subsequently washed in from above.
ORISKAKy FAUNA OF BECK AFT MOUNTAIN 99
tween the retreating and invading faunas there is seldom evidence of a commingling of species. In the Helderberg section the commonly occurring fossils are Tentaculites gyracanthus Eaton, Spirifer vanuxemi H., Brachyprion varistriatum H., Megambonia? aviculoides H., Modiolopsis? dubia H., Beyrichia notata H. and B. trisulcata H.
The number of forms which were assigned by Prof. Hall to this horizon is 22, but some of them, particularly species of Holopea, Euomphalus, Oncoceras and Cyrtoceras, are of quite uncer- tain character. It has been remarked in a foregoing paragraph that the Tentaculites which are so abundant in eastern New York appear only with extreme rarity in the westward extension of the formation. At Union Springs, Cayuga co., the Manlius limestone has a more prolific fauna than has been observed elsewhere west of Herkimer county. Atten- tion was specially directed to this occurrence by Prof. S. G. Williams in a paper read before the American association for the advancement of science in 1885 and an article entitled "Note on the Lower Helderberg rocks of Cayuga lake", which appeared in the report of the New York state geologist for 1896, p. 10-12. Prof. Williams here gave a list of 26 species which he had identified from localities in this vicinity.
The most favorable spot for the examination of this fauna is in the rocks exposed on Frontenac island, just off the village of Union Springs. These are blue gray hard limestones from 8 to 10 feet in thickness, lying over the Eondout waterlimes, which are about 25 feet thick and carry Eurypterus remipes. Above the blue limestones waterlimes again appear, and for a while the fauna of the Frontenac island beds retreats, but reappears in the hydraulic strata lying below the Oriskany sandstone at Yawger's woods, 2 miles north of the village. My identifications of the species do not in all respects agree with those made by Prof. Williams, and our differences concern almost entirely such species as he recorded as found in the eastern subdivisions of the Helderbergian.
The limestone layers are characterized by two distinct beds of a Stromatopora or Stromatoceriura, and it is between these that
100 • NEW YORK STATE MUSEUM
the more productive fossiliferous beds occur. In part these beds are made up of masses of the lamellibranch Ilionia sinuata, a species described by Hall as Anatina? sinuata, from Herkimer county. It is by far the most abundant of all the species here present.
Ilionia is a generic type of strong Siluric cast, represented by the well-known and highly characteristic Lucina priscaof Wahlen- berg, from the upper beds on the island of Oesel. Other species are a form of Hormoceras, a strong Siluric type, and a Cyrtocerasor Gyroceras making more than one revolution, a small form of O n c o - c e r a s , perhaps that identified by Williams asO. ovoides Hall, but which appears to me different in several respects. This genus, O n c o - c e r a s again indicates the Siluric affinity of the fauna. There are species of Orthoceras both smooth and annulated, which have not yet been satisfactorily identified. Among the gastropods are some species of Holopea which are hardly identifiable. Also an Euomphalus, which may be compared with the E. sinuatus Hall of this horizon. Spirifer vanuxemi and Brachyprion varistriatura, which occur throughout the extent of the limestone east and west, are here quite abundant. Also the Atrypa sulcata Vanuxem, which proves to belong to the genus Whitfieldella, and a large unidentified form of the genus Chonetes. I look on the discovery in this fauna of Halysites eaten ulatus as of much significance. Though not abundant, the species is thoroughly characteristic. Another coral is present, doubtless that referred to by Prof. Williams as Zaphrentis sp., which I find to have the characters of the new genus Charactophyl- 1 u m , and to be most closely allied to the C. (Cyathophyllum) radi- culum Rominger, of the Niagaran fauna. A few other species have been observed but not in condition for satisfactory identification.
It is perfectly clear without farther argument that the types expressed in the foregoing list are very positively indicative of Siluric age, and, furthermore, that they have nothing in common with the true Helderbergian fauna. No single species of the list and none of the generic forms here cited, such as Hormoceras, Oncoceras, Ilionia (or Platy- mermis), Whitfieldella, Halysites and Charactophy Hum,
ORISKANY FAUNA OF BECRAIT MOUNTAIN 101
pass over into later faunas. No additional evidence is required to establish the individuality of the fauna of the Manlius limestone and its affiliation with the SUuric. As the names of several species appear on Prof. Williams's list which belong to the Helderbergian, I feel it necessary to add that of the following I have found no trace : Lingula recti- latera, Or thos trophia s tr ophomen oides^ Nucleospira ventricosa, Holopea danai.^
* Dr Grabau's study of the organic remains of the Manlius limestone of Erie county {op. cit.) which was to some extent based on collections from this horizon in the N. Y. state museum have resulted in the identification of a considerable number of species. As this work has issued since the foregoing matter was in type his results are briefly presented. Following are the species:
Nematophytum crass um Penhallow
Cyathophyllum hydraulic um Simpson (MSS.). This species is every- where abundant throughout the western extent of the Manlius waterlimes.
Orthothetes hydraulica Whitfield. Originally described from Bellville and Greenfield O,
Spirifer eriensis Grabau. This species has commonly passed under the name of S. vanuxemi which, as noted by Whitfield and others, is hardly distinguishable from S. crispu» as it occurs in the Coralline limestone at Schoharie.
Whitfieldella sulcata Vanuxem
Whitfieldella cf. rotundata Whitfield
Whitfieldella ef. laevis Whitfield
Loxonema ? sp.
Pleurotomaria ? sp.
Trochoceras gebhardi Hall
Leperditia scalaris Jones
The most striking feature of this little fauna is its similarity to that of the Coralline limestone of eastern New York, the representative of the Niagaran formation in that region. This is seen in the similarity of Spirifer eriensis to the S. crispus as identified by Hall from that formation, of Whit- fieldella cf. rotundata with W. nucleolata of the same formation. Tiie presence of Trochoceras gebhardi in both and the close relationship of Leperditia scalaris Jones with L. jonesi Hall of the Coralline limestone. Dr Grabau's conclusion from the study of this fauna as well as of the tectonic relations of the strata in Erie county emphasizes the strongly Siluric character of the Manlius limestone.
I EXPLANATION OF PLATES
104 NEW YORK STATE MUSEUM
PLATE 1
Phacops logani Hall
Page 21 Fia. .
1, 2 Superior and profile views of a cephalon, showing the
minute genal spinule and faint glabellar furrows 3, 4 Portions of other cephala in which the eye is retained
5 A pygidium, showing the duplication of the lateral ribs.
x3
Dalmanites (Synphoria) stemmatus sp. nov.
(See Plate 2) Page 15
6 An incomplete internal cast of the cepbalon, showing the
frontal ornament and the fused glabellar lobes 7, 8 More complete specimens of the cephalon, showing general form and structure 9 A front view of the latter, showing the elevation of the
shield and eyes 10 A part of the head taken from a mold of the exterior and showing the marginal ornament in detail 11, 12 Hypostomas of two individuals
13 A small and unsymmetrical pygidium
14 The internal cast of a large pygidium, its apparent width
greatly increased by the loss of the posterior border 15, 16 Two pygidia of normal outline and structure
ClinSKAXV F.VLXA.
Memoir 3 N.Y. State Museum.
Plate 1.
G B Simpson del
James B.Lyon. State Printer
Philip Ast hth
I
OEISKANY FAUKA OF BECEAFT MOUNTAIN 105
PLATE 2
Dalmanites (Synphoria) stemmatus sp. nov.
(.See Plate 1)
1, 2 The frontal doublure of two cephala showing the marginal ornament
Dalmanites (Synphoria) stemmatus. var. convergens var. nov.
Page 19
3 An incomplete and somewhat distorted cranidium
4 A pygidium of usual size and proportions
5 Another pygidium more obtuse at the extremity
Dalmanites bisignatus sp. nov.
Page 19
6-8 Pygidia of this species, showing the form and character of ornament
Phacops correlator sp. nov.
Page 20
9 A cephalon restored in outline, showing the dalmanitiform character of the glabella and the rounded cheeks. x3
Dalmanites phacoptyx Hall & Clarke
Pagel»
10 A portion the very characteristic pygidium of this sjtecies Proetus conradi Hall ,
Page 29
11-13 Portions of the cephalon, more or less flattened
14 An uncompressed glabella with traces of the lateral furrows
15 The pygidium
16 Internal cast of an essentially entire individual
106 ^N^"^ YORK STATE MUSEUM
Cordania hudsonica sp. nov.
FlO. Page 34
17 An internal cast of the pygidium. x2
18 A pygidium with portion of the exterior showing the orna-
ment. x3
Cordania becraftensis sp. nov.
Page 22
19, 20 Two pygidia, showing surface markings. x3 21, 22 Two cranidia, natural size
23 A portion of the cranidium, enlarged to show the character of the ornament. x2
Cyphaspis minuscula Hall (sp.)
Page 24
24, 25 Two cranidia, x3
Acidaspis tuberculata Conrad
Page 25
26 The cranidium. x3
Autodetus beecheri Clarke
Page 26
27 The internal cast of the spiral tube lying in the natural
mold of the fossil. x3
28 A specimen showing the cast spiral tube and a part of
the exterior wall
29 The exterior of the species with a Fistulipora grow-
ing on the surface
30 The interior wall of the shell with the casts of the spiral
tubes removed except that of the initial volution which lies on the surface of attachment. x3
31 The initial form of the shell, attached to the surface of a
brachiopod. This is a highly convex bulb, which is not overlapped by the early part of the first volution. x5
32 A somewhat more progressed condition with more of the
spiral tube remaining. x5
ORISKANV FAUXA.
Memoir 3. NY. State Museum
Plate 2.
G.B Simpson del
James B.Lyon, State Pnnter
Phihp Ast bth
I I
OEISKANT FAUNA OF BECKAFT MOUNTAIN 107
Spirorbis assimilis sp. nov.
Fio. Page 36
33 A group of these tubes on the internal surface of a valve
ofMeristella
34 The upper surface of a specimen. xlO
Cornulites cingulatus Hall
Page 27
35 A small tube attached to the edge of a valve of Ortho-
thetes. x3
36 A larger example. x3
37 A large tube, showing surface of attachment to a Fistu-
lipora. x3
38 Internal cast of another specimen. x3
108 NEW YOEK STATE MUSEUM
PLATE 3
Tentaculites (?) acus sp. nov.
Page 28 Fia.
1 A specimen which shows the smooth exterior and the
annulated or insheathed cast of the interior. x3
2 The exterior, showing low annular depressions
3 The internal cast. x3
4-7 Specimens of natural size, showing the generally smooth or slightly corrugated exterior
Tentaculites elongatus Hall
Page 37
8 The initial end of a specimen, showing its smooth exterior
and the character of the internal cast. x5
9 External and internal casts. x2
10 Enlargement of the apical portion of the tube, showing
the smooth area and gradual development of annulations and concentric lines. xlO
11 The character of the surface at maturity. x5
12 A portion of the exterior, natural size
Diaphorostoma desmatum sp. nov.
Page 29
13-15 Three views of an average specimen
16, 17 Views of other specimens
18 The upper surface of a larger shell, showing the lineation
19 An enlargement of the surface characters. x6
Cyrtolites expansus Hall
Page 28
20 Upper view of a slightly distorted specimen, for the most
part an internal cast
OHISKAXV FAIJXA.
Memoir 3. NY, State Museum.
Plate 3,
n
I
6
^Uliilii,,
0 E Simpson del
James B Lyon State Pnnter
Phihp Ast hth
4' *.
51
1
ORISKANY FAUNA OF BECRAFT MOUTSTTAIN 109
21 Posterior view of the same specimen showing the sub-
apical groove
22 An enlargement of the external ornament. x6
23 A smaller example Avith more strongly developed median
carina
Strophostylus expansus Hall
Page 30
24 An upper view of a characteristic specimen
Diaphorostoma ventricosum Hall
25-28 Views of various specimens showing the general aspect of the shell in this fauna
Platyceras cf. gebhardi sp. nov.
Page 80
29 Lateral view of an internal cast of this species
110 NEW YORK STATE MUSEUM
PLATE 4
Actinopteria communis Hall
Page 34 Fia.
1, 2 Eight and left valves of the same shell, shovring the char- acter of the surface
Pterinopecten signatus sp. nov.
Page 33
3 A left valve showing the form and external ornament Pterinopecten proteus sp. nov.
Page 32
4-7 Right and left valves of this species, which show the wide variation in external characters
8 An enlargement of the surface characters of one of these
shells. x2
Pterinopecten pumilus sp. nov.
Page 33
9 The right valve of this species, x3
Actinopteria insignis sp. nov.
Page 35
10, 11 Two left valves showing the form and external characters
of the species 12, 13 Enlargement of the surface characters from different parts
of the same shell. x5
Pterinopecten subequilateralis Hall (emend^.
Page 31
14 An external cast of the surface of a right valve, showing the absence of radial ornament
()HISKAX\^ FAl XA.
Memoir 3.N Y State Museum.
Plate 4.
B Simpson del
James B Lyon. State Printer
Phihp Ast lith
OEISKANY FAUNA OF BECRAFT MOUNTAIN" H]
Megambonia crenistriata sp. nov.
Fia.
Page So
15, 16 Two left valves, showing the outline, contour and ornament li -Enlargement of the surface. x5
Cypricardinia indenta Hall
Page 36
18 A nearly complete right valve. x2
19 Another valve, natural size
20 Enlargement of a portion of the surface. x5
Conocardium inceptum Hall (?)
Page :i7
21 A specimen, natural size
22 Another shell enlarged, showing the character of the sur-
face. x3
23 The opposite valve fi-om a larger specimen. x3
112 HEW YORK STATE MUSEUM
PLATE 5
Cryptonella (?) fausta sp. nov.
Page 38 Fia.
1-3 Dorsal, profile and ventral views of a typical example 4-6 Similar views of another shell showing the depressed con- vexity of the brachial valve 7,8 Ventral and profile views of another example
Oriskania sinuata sp. nov.
Page 38
9, 10 Dorsal and profile views of a specimen which show the convexity of the brachial valve
11 Another example showing the same characters
12 An example showing the muscular and vascular scars on
a cast of the brachial valve
Megalanteris ovalis Hall
Page 40
13,14 Dorsal and profile views of a characteristic example
15 An enlargement of the surface showing the imperforate
exterior layer and the perforate inner layer of the shell
16 An internal cast of the pedicle valve showing the muscular
and vascular scars
Rensselaeria ovoides Eaton
Page 39
17, 18 Profile and dorsal views
19 Internal cast of a pedicle- valve showing the muscular impressions
Camarotoechia sp. cf. dryope Billings 20, 21 Profile and ventral views of an imperfect specimen
Camarotoechia oblata Hall 22 An internal cast of a pedicle-valve
0RISKA:N^1" FAt^XA.
Memoir 3,N.Y. State Museum
Plate 5.
0 B Simpson del
James B Lyon, State Printer
Phihp Ast hth
OBISKAKT FAUNA OF BECBAFT MOUNT AtN 113
Coelospira concava Hall
Page 43 Fio.
23 Dorsal view. x3
24 Ventral view. x2
25 The interior of the brachial valve. x2
26 The interior of the pedicle- valve showing the muscular
impressions. x3
Coelospira dichotoma Hall
Page 43
27 Dorsal view of the exterior. x3
28 Ventral view of the exterior of the same specimen. x3
29 Internal cast of the pedicle-valve showing the muscular
scars. x3
30 View of the interior of the brachial valve. x2 31, 32 Dorsal and ventral views of the exterior. x2
Leptocoelia flabellites Conrad
Page a
33, 34 Dorsal and ventral views of an average specimen 35, 36 Dorsal and ventral views of the specimen in which the fold and sinus are not so pronounced
114 NEW YORK STATE MUSEUM
FLATE 6
Trematospira multistriata Hall
Page 43 Fio.
], 2 Dorsal views showing the character of the exterior
3 Dorsal view of a smaller shell with strongly duplicate
plications
4 Enlargement of the surface of the shell. x5
Meristella lentiformis sp. nov.
Page 44
5, 6 Dorsal and profile views of a characteristic specimen 7 Dorsal view of an internal cast showing the existence of a strong median septum in the brachial valve 8-10 Dorsal, profile and ventral views showing the character- istic contour of the species 11 Internal cast of the pedicle-valve showing the strong muscular scar
Meristella ? vascularia sp. nov.
Page 45
12-14 Internal casts of the jiedicle- valve showing strong dental lamellae, pedicle cavity and muscular impressions and the radiating sinuses over the vascular region
Cyrtina varia sp. nov.
Page M
15 Enlargement of the surface showing its pustulose character 16-18 Anterior, posterior and profile views of an average specimen 19 Anterior view of a larger specimen with convex pedicle- valve 20-22 Three views of a smaller specimen
ORTSKANir FAUXA.
Memoir 3.N.Y, State Museum,
Plate 6.
B Siriipsoti del
James B . Lyon, State Printer
Phihp Ast hth
I
ORISKANY FAUNA OF BECRAFT MOUNTAIN 115
Spirifer saffordi Hall
Page 48 Fio.
23, 24 Exteriors of pedicle-valves showing the fimbriate surface. In fig. 23 the rows of these fimbriae are more num- erous and closely crowded than in the other. x2
25 A portion of the surface enlarged showing the character
of the spine bases on the concentric growth lines. xlO
Spirifer murchisoni Castelnau
Page 46
26 An incomplete brachial valve
27 A ventral valve of large size showing the fimbriate
surface
28 A specimen showing the brachial valve with the internal
cast of the ventral muscular impressions
29 An enlargement of the surface showing the concentric
rows of short hollow spinules. xlO
30 A similar enlargement in which only the bases of the
spinules are shown. xlO
I
116 NEW TOEK STATE MUSEUM
PLATE 7
Chonetes hudsonica sp. nov.
Page 49 Tia.
1 The exterior of the pedicle-valve
2 The interior of the brachial valve
3 An external cast of the pedicle-valve 4, 5 Pedicle and brachial valves. x2
6 The surface striations enlarged. x4
Chonostrophia complanata Hall
Page 50
7 Ventral view of a small specimen
8 Internal cast of a pedicle-valve of average size
9 The interior of the pedicle-valve
10 Internal cast of a pedicle- valve with somewhat more
elongate outline
11 Exterior of a pedicle- valve of a large individual
12 Enlargement of the surface. x5
13 Interior of a large pedicle- valve
AnopHa nucleata Hall
Page 51
14 Dorsal view of a specimen retaining both valves. x3
Orthothetes becraftensis sp. nov.
Page 51
15 The interior of a pedicle- valve 16, 17 Exteriors of pedicle- valves
18 The cardinal process of the brachial valve. x3
19 The exterior of a small brachial valve, x2
20 Exterior of a small pedicle-valve
21 The interior of a young pedicle-valve attached by the
substance of its shell to the surface of a M e r i ■ Stella. x2
ORlSIv^ViV^" FAUXA
Memoir 3 NY State Museum
Plate 7.
G B Simpson del
James B Lyon State Printer,
Phihu Asl lith.
ORISKANY FAUNA OF BECRAFT MOUNTAIN 117
22 The interior of an incomplete brachial valve showing
the cardinal process
23 Interior of the pedicle-valve showing the cardinal area
and deltidium
24 Posterior view of a specimen bearing conjoined valves
and showing the elevated cardinal area
25 Cardinal process of the brachial valve. x3
26 A portion of the external surface enlarged
27 The cardinal area of the pedicle-valve showing the
deltidium, x3
Leptostrophia oriskania sp. nov.
Page 53
28 An enlargement of the external surface. x5
29 Sculpture cast of the pedicle-valve
30, 32, 34 The external surface of pedicle-valves showing their va- riations in outline and the undulated surface 31, 35 The exterior of brachial valves
Leptostrophia cf. magnifica Hall
Page 93
36 The exterior of the ventral valve of a small shell which
may represent this species
Stropheodonta lincklaeni Hall
Page 52
37 A specimen of the dorsal valve showing a portion of
the interior with cardinal process and also a part of the external surface
118 NEW YORK STATE MUSEUM
PLATE 8
Brachyprion schudiertanum sp. nor.
Page 66 Wta.
1 The apical portion of the brachial valve showing the
coarse angular striae similar to those of Stropheo- donta arata Hall. x3
2 The exterior of the brachial valve
3 External cast of brachial valve
4 The exterior of an incomplete pedicle-valve
5 The exterior of a brachial valve
6 An imperfect interior of the brachial valve
7 An enlargement of the external surface showing the
character of the ornament. x5
Brachyprion majus sp. nov.
Page 5«
8 The character of the external surface. x5
9 The exterior of the pedicle-valve, the umbo of which
is made somewhat too conspicuous
10 The interior of the pedicle- valve
11 An internal cast of the pedicle- valve showing the
muscular impressions
12 The exterior of the brachial valve
13 The cardinal area of the pedicle-valve showing the short
rows of denticles on either side of the deltidium
Rhipidomella oblata Hall
Page 58
14, 15 Views of the exterior
Crania pulchella Hall and Clarke
Page 58
16 An incomplete specimen showing marks of attachment
17 A more complete example. x3
18 Two specimens exfoliated at the apex
OHISKAIVV FAU^-A
Memoir 3.N.Y State Museum.
Plate 8 .
G B Sirnpsoii del.
James B.Lyon, State Printer
Phihp Ast hth
OEISKANY FAUNA OP BECEAFT MOUNTAIK 119
Crania cf. bella Billings
_^ PageU
rta.
19 The upper valve
20 Profile view of a very young example showing the
regular conical form, xlO
Pholidops sp.
Page 59
21 The interior of one of the valves
22 The exterior. x5
Pholidops terminalis Hall
Page S»
23 The exterior of the larger valve. x3
24 The interior showing the muscular scars. x3
25 A valve showing replacement of the shell by a series
of chalcedonies formed concentrically about centers of silicification
120 NEW yOKK STATE MUSEUM
PLATE 9
Cladopora styphelia sp. nov.
Page 64 Fro.
1, 2 The exterior of branches of this species Cladopora smicra sp. nov.
Page 63
3-5 Branches of this coral, natural size
6 An enlargement of the exterior. x3
Vermipora streptocoelia sp. nov.
Page 63
7 Portion of the frond showing the character of the tubes
as they emerge on the surface. x2
8 The same species with the external silicified layer re-
moved showing the meandering character of the tubes in the substance of the coral beneath the surface. x2
Hederella ramea sp. nov.
Page 62
9 A characteristic colony showing the diffusely branching
frond, the whole being attached to a specimen of Leptostrophia oriskania. x3
Hederella magna sp. nov. and Hederella graciliora sp. nov.
Page 61, 63
10 The surface of a brachiopod covered with fronds of
these species, the coarser frond with the larger tubes being Hederella magna and the finer zoarium H. graciliora. x2
Hederella arachnoidea sp. nov.
Page 61
11 The internal surface of the glabella of Dalmanites
stemmatus covered with the fine fronds of this species. x2
ORISKAJNY FAtJXA.
Memoir 3. N.Y. State Museum.
Plate 9
v) *\.
0 5 Simp sen del
James B.Lyon. State Printer
Ph'.hp Ast liih
t
i
ORISKANY FAUNA OF BECRAFT MOUNTAIN
121
Edriocrinus becraftensis sp. nov.
Page 62
Fio.
12, 13 Views of the calyx of this crinoid
Beyrichia sp. ?
14 View from the anterior margin. xlO
15 View showing the outline and nodes of the valve. xlO
INDEX
The superior figures tell the exact place on the page in ninths; e. g. 77^ means page IT, beginning in the third ninth of the page, i. e. about one third of the way down.
Bellerophon sp.? 28'.
Beyrich, E., on Helderbergian faunas, 83*.
Acaste cf. anceps, 20^-21*. Acidaspis tuberculata, 25'.
explanation of plate, 106^. Actinopteria communis, 34*, 35^ explanation of plate, 110^.
insignis, 35i. explanation of plate, 110'.
textilis, 349, 35^. Albany county, Oriskany fauna, IIK Ami, H. M., on fauna of Gasp^ limestones,
80*. Anastrophia, 41*. Annelids, 26^-28*. Anoplia nucleata, 51*.
explanation of plate, 116*. Anthozoa, 628-64«. Atrypa reticularis, 15^. Aulopora cf. schoharie, 64*. Autodetus beecheri, 266, 272.
explanation of plate, 106^. Avicula communis, 34^.
recticosta, 33^.
subequilateralis, 31'-322. Aviculopecten sp.? 34*.
Barrett, S. T., on sections exposed at Port
Jervis, 76^. Becraft mountain, stratigraphic structure,
6'-15^ Beecher, C. E., Notice of a new Lower
Oriskany fauna in Columhia county, 6*.
Beyrichia sp., explanation of plate, 121^. Billings, E., on fauna of G-asp6 limestones,
802. Brachiopods, description of Oriskany
species, 38''-59^; in the Helderbergian,
85<-863, 901, 92s_936^ 944, Brachyprion aratum, 57^.
majus, 549-56«, 57^.
explanation of plate, 118^.
schuchertanum, 55^, 56*, 56^-57*. explanation of plate, IIS^.
varistriatum, 55^. Bryozoa, description of Oriskany species,
598-625; in the Helderbergian, 86*, Ql^,
94'.
Camarotoechia sp.? 41^.
barrandii, 40*.
dryope, 41^ explanation of plate, 112'.
(?) fltchana, 40».
oblata, 411.
explanation of plate, 112®.
pliopleura, 41^. Centronella, 38^. Cephalopods in the Helderbergian, 84*-
851, 927^ 939. Chaetetes (Monotrypella) arbusculus, 641
INDEX
123
Chonetes cf. arcuata, UK complanatus, 50^. dawsoni, 50^ hudsonlca, 49^-50^
explanation of plate, 116^ melonica, 50^. Chonophyllum, 15^ Chonostrophia complanata, 50^-51*. explanation of plate, 116^ helderbergia, 51^. reversa, 51^. Cirripeds, 26^. Cladopora smicra, 63^.
explanation of plate, 120^ styphelia, 63^, 64}. explanation of plate, 120^ Clarke, J. M., list of species of Oriskany fauna, 6^; previous study on age of Helderbergian, 83*. Coelospira Camilla, 42*. cf. Camilla, 14^, concava, 42^.
explanation of plate, 113^ dichotoma, 42^. explanation of plate, 113^. Coenograptus gracilis, 7^. Coleolus sp.? 281. Conocardium concinnum, 37^. cuneus var. nasutum, 37'. inceptum, 37^ explanation of plate, 111*. Conodonts, 26*. Conularia desiderata, 28°.
cf. desiderata, 28^. Corals in the Helderbergian, 86*, 92^, 95^
Cordania becraftensis, 228-242. explanation of plate, lOG^. cyclurus, 23^-242. hudsonica, 24^. explanation of plate, 106^ Cornulites, 28*. cingulatus, 27^ explanation of plate, 107^. Corycephalus regalis, 17*, 18*. Crania bella, 58«. cf. bella, 58^-59^
explanation of plate, 119^. pulchella, 58*. explanation of plate, 118^ Crinoidea, description of Oriskany species, 625; jn tjjg Helderbergian, 86*, 91^, 95^. Cryptouella, 39^ (?) fausta, 385-395. explanation of plate, 112^. Cyphaspis coelebs, 24^ minuscula, 245. explanation of plate, 106*. Cypricardinia indenta, 36^ explanation of plate, 111^. lamellosa, 365. cf. lamellosa, 36*. planulata, 36*. Cyrtina dalmani, 49^. cf. dalmani, 49^. rostrata, 49^. varia, 49^.
explanation of plate, 114*. Cyrtolites expansus, 28^-29*.
explanation of plate, 108^-9^. Cystids in the Helderbergian, 865, 952
124
NEW YOB.K STATE 31USEUM
Salmanella perelegans, ST'-SS*.
subcarinata, 58^ Dalmanites anchiops, W, W, n\ IS^. var. sobrinus, 18*. bisignatus, 19^-20^
explanation of plate, 105^ booth!, 18^.
var. calliteles, 18'. calypso, 18*. dentatus, IT^, 18', 20». diurus, 18*. dolphi, 175, 189. (Pterygometopus) eboraceus, 18*.
intermedins, 18*. macrops, 18*. myrmecophorus, 18*. phacoptyx, 19^.
explanation of plate, 105'^. pleuroptyx, 16', 172, igg^ 20^. (Corycephalus) regalis, 17*, 18*. (Odontocephalus) selenurus, 17', 18*. (Synphoria) stemmatus, 15^-19^. explanation of plate, 104*, 105^ var. convergens, 19'.
explanation of plate, 105'. verrucosus, 17^. vigilans, 17^. Dana, J. D., on geology of Becraft moun- tain, 72. Davis, W. M., on geology of Becraft
mountain, 7^. Dawson, J. W., cited, 81«. Description of fauna, 15*-719. Devonic age of Helderbergian fauna, 82'-
101». Devonic system, base, 82'-101'.
Diaphorostoma desmatum, 29''-30'. explanation of plate, 108*.
lineatum, 30'.
ventricosum, 29'-30*. explanation of plate, 109'. Dictyonema crassum, 64*.
splendens, 64'.
cf. splendens, 64*. Didymograptus Sagittarius, 7\
tenuis, 7*. Distribution of Oriskany fauna, 721-82'.
Eatonia medialis, 40'.
peculiaris, 40^. Edriocrinus becraftensis, 62*. explanation of plate, 121^
sacculus, 62*. Ells, E. W., on fauna of Gasp<S limestones,
80'. Explanation of plates, 104-21.
Fauna, Oriskany, description, 15*-71^; of
Gasp6 limestones, 80^-822; of Manlius
limestone, OSMOl'. Faunal values of Oriskany species, 68*-
71*. Favosites, 15^ Fenestella (Unitrypa) acclivis, 60*.
biseriata, 61^.
(Hemitrypa) columellata, 61'.
(Unitrypa) lata, 60'. Fistulipora, 15^.
Gaspe limestones, fauna, 801-82^. Gastropods, description of Oriskany
species, 28'-379; in the Helderbergian,
852, 89', 941.
INDEX
125
Girty, G. H., on sponges and coelentrates of Helderbergian, 84^.
Glenerie, Oriskany fauna, 74^.
Goniophora sp.? 35^
Grabau, A. W., study of Manlius lime- stone of Erie county, 98^, 101^
Graptolites in the Helderbergian, 86'', 95^.
Hederella arachnoidea, 61''. explanation of plate, 120*. flliformis, 62^ graciliora, 61', 62^
explanation of plate, 120^. magna, Ql\ 62*.
explanation of plate, 120''. ramea, 62^. explanation of plate, 120*. Helderbergian fauna, Devonic age, 82^- 101'; limits, 84'; Siluric characters, 84''- 86«; Devonic characters, 871-93*. Hemitrypa columellata, 61^ Hipparionyx proximus, 52^ Homalonotus sp.? 26^
major, 26^. Hjdrozoa, 64*.
Isotrypa, 61^.
Kayser, E., on Helderbergian faunas, 83^. Kingston, Oriskany fauna, 73^.
lamellibranchs, description of Oriskany
species, 31*-37*; in the Helderbergian,
853, 898^ 928, 942_ Leptaena? nucleata, 51^
rhomboidalis, 15^, 54^, 57'. Leptocoelia acutiplicata, 43^
Qabellites, 42M3'. explanation of plate, 113^.
Leptostrophia becki, 53*.
cf. becki, 531
blainvillii, 50^.
magniflca, 53^. explanation of plate, 117*.
oriskania, 53'-54^.
explanation of plate, 117*.
perplana, 53^. Lichas pustulosus, 25'.
cf. pustulosus, 25'. Lichenalia cf. crassa, 60*. Lingula rectilatera, 59^.
cf. rectilatera, 59''. Logan, Sir William, on Gasp6 limestones,
802, 818. Lyriopecten sp.? 34^
Manlius limestone, fauna, 98M01'. Mather, W. W., on geology of Becraft
mountain, 6^-7^. Megalanteris ovalis, 40^.
explanation of plate, 112*. Megambonia bellistriata, 35^.
cardiiformis, 35''.
crenistriata, 35*, 36^. explanation of plate, 111^
lamellosa, 31^ Meristella cf. laevis, 45*.
lata, 453.
lenta, 44^.
lentifo-rmis, 44^-45^. explanation of plate, 114*.
(Pentagonia) unisulcata, 44*.
(?) vascularia, 45*-462. explanation of plate, 114*. Metaplasia pyxidata, 48'. Monotrypella arbusculuB, 64*.
126
KEW YORK STATE MUSEUM
Nature and distribution of Oriskany
fauna, 721-823. Nomenclature of geologic formations, 8«-
12».
Odontocephalus selenurus, 15^, 17^, 18'. Orange county, Oriskany fauna, 75*-lP;
Oriskany strata, 75^ Oriskania navicella, 38*.
sinuata, 38^. explanation of plate, 112^ Oriskany fauna, description, 15^-71'';
faunal values, 68^-719; vertical range,
651-68^; nature and distribution, 72^-
823; description of plates, 104-21. Oriskany sandstone, original, 781-799. Orthis oblata, 58'.
cf. oblata, 58^.
perelegans, 57*. Orthonycbia tortuosa, 301 Orthothetes arctostriata, 52^.
becraftensis, 51^-52^ explanation of plate, 116^-173.
deformis, 52*.
woolworthana, 52*.
Pentagonia unisulcata, 44*. ' Phacops, 14^.
anceps, 20''.
(Acaste) cf. anceps, 20«-2l5.
cf. bombifrons, 14^.
braziliensis, 21^.
correlator, 20«-2l5. explanation of plate, 105«.
cristata, 22*.
logani, 216-221 explanation ot plate, 104*. ,
Phacops pipa, 21^ 22*.
rana, 22^. Pholidops sp.? 59^
explanation of plate, 119^. arenaria, 59'. terminalis, 59^. explanation of plate, 119*. Plates, explanation of, 104-21. Platyceras gebhardi, 305-311. cf. gebhardi, 30^, 31i.
explanation of plate, 109*. nodosum, 31^. tortuosum, 30*. Pleurotomaria, 29^. Plumulites sp. 26*. Polypora, 60^.
separata, 60^. Polyporella cf. compressa, 60^ Port Jervis, fauna, 76*. Proetus angustifrons, 25*. clarus, 25*. conradi, 25i.
explanation of plate, 105«. rowi, 25*. Pterinea sp.? 31* Pterinopecten bellulus, 33*. proteus, 323-333, 33^.
explanation of plate, 110*. pumilus, 339-343.
explanation of plate, 110'. signatus, 33*.
explanation of plate, 1103. subequilateralis, 31''-322.
explanation of plate, llO^. terminalis, 33*.
INDEX
127
Pteropods, description of Oriskany species,
28^; in the Helderbergian, So^, MK Pterygometopus eboraceus, 18^ (?) Ptychonema helderbergiae, C3i.
Rafinesquina alternata, 55^. Rensselaeria oralis, 40^.
ovoides, 39^. explanation of plate, 112'.
suessana? 40^. Retepbrina, 61^ Rhipidomella oblata, 58^.
explanation of plate, 118*. . Rhombipora rhombifera, 59'. Rhjnchonella barrandii, 40'.
dryope, 41^. Ries, Heinrich, report on geology of
Orange county, 75^ Ruedemann, Rudolf, observations on
Kingston beds, 73*.
Schoharie county, Oriskany fauna, 77^. Schuchert, Charles, on age of Helder- bergian, 83^ Spirifer antarcticus, 47*.
arenosus, 46*.
arrectus, 46*. var. antarcticus, 47®-48^
capensis v. Buch, 48?.
chuquisaea, 48^.
cf. fimbriatus, 48*.
gaspensis, 50^.
hawkinsi, 48^.
murchisoni, 46'-48'. explanation of plate, US'.
orbignyi, 48^
P^rforatus, 43*.
Spirifer pyxidatus, 48'. raricosta, 14^. saffordi, 481
explanation of plate, 115^.
varicosus, 151. :Spirorbis assimilis, 26^-272.
explanation of plate, 107^. Spongiae in the Helderbergian, 92=, 95^. Stictopora sp.? 60^.
granulata, 60^.
Stratigraphic structure of Becraft moun- tain, 6M53. Streptorhynchus pandora, 15^. Stromatopora, 15^.
Stromatoporoids in the Helderbergian, 955.
Stropheodonta, 54*.
demissa, 57^
liucklaeni, 528-53*. explanation of plate, 117''.
cf. radiata, 56^
varistriata, 55^ var. arata, 55*. Strophodonta lincklaeni, 52».
magnifica, 53*. Strophomena rugosa, var. ventricosa, 57*. Strophostylus expansus, 30^.
explanation of plate, 109^. Synphoria stemmatus, 15^-19*.
Tentaculite limestone, 98^ Tentaculites ? acus, 28^.
explanation of plate, 108^. elongatus, 27«, 28i.
explanation of plate, 108*. cf. elongatus, 27'.
128
NEW TOKK STATE MUSEUM
Trematospira multistriata, 43'. explanation of plate, 114^.
perforata, 43^. Trilobites, description of Oriskany species,
15<-262; in the Helderbergian, 848, 372^
92«, 93*.
Ulster county, Oriskany fauna, 72'-75^ Unitrypa acclivis, 60*.
lata, 60». Van Ingen, Gilbert, observations on
Kingston beds, 73^
Vermipora serpuloides, 63*. streptocoelia, 63^. explanation of plate, 1201 Vertical range of Oriskany fauna, 6oM8^. Vertumnia, 32i, 343.
Williams, S. G., on Lower Helderberg rocks of Cayuga lake, 99*.
Zaphrentis, 14®, 15^. Bp. 62«.
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