UC-NRLF

C 2 fill MD7

•EBKEltY

LIBRARY

EARTH

SCIENCES

LIBRARY

LIBRARY

OF THF,

UNIVERSITY OF CALIFORNIA.

GIFT OF

Class

University of the State of New York

New York State Museum

FREDERICK J. H. MERRILL Director
JOHN M. CLARKE State Paleontologist

Memoir 5

GUELPH FAUNA IN THE STATE OF NEW YORK

JOHN M. CLARKE AND RUDOLF RUEDEMANN

Preface - 3

Introduction 4

Typical Guelph dolomites of

Ontario and their fauna - 4
Guelph fauna of New York and its

stratigraphic relations - 5

Historical 5
Section of the dolomites at Shelby,

Orleans co. 9

Niagara county 13
Other manifestations in Orleans

county - - - 17

Monroe county 17

Wayne county - 20
Southern Ontario — the section at

Hamilton - 20

Summary - - 22

Fauna of the Guelph dolomite in west-
ern New York - 23
Anthozoa 23
Hydrozoa - -36
Brachiopoda - 38
Lamellibranchiata - 47
Gastropoda - 51
Cephalopoda - 77
Annelida 105
Ostracoda - - 106
Trilobita 107
Synoptic list of Guelph fossils of New

York - 109
Conditions of life and sedimentation 1 14

Distribution of the Guelph - 122

Explanation of plates - 139

Index - - - 187

ALBANY

UNIVERSITY OF THE STATE OF NEW YORK
1903

EARTH
SCIENCES
UB8A8Y

f

University of the State of' New York

REGENTS

With years of election

1892 WILLIAM CROSWELL DOANE DD. LL.D. Vice Chancellor, Albany
1873 MARTIN I. TOWNSEND M.A. LL.D. - - Troy
1877 CHAUNCEY M. DEPEW LL.D. New York

1877 CHARLES E. FITCH LL.B. M.A. L.H.D. - - Rochester

1878 WHITELAW REID M.A. LL.D. New York
1881 WILLIAM H. WATSON M.A. LL.D. M.D. - - Utica
1881 HENRY E. TURNER LL.D. - Lowville
1883 ST CLAIR MCKELWAY M.A. L.H.D. LL.D. D.C.L. - - Brooklyn
1885 DANIEL BEACH Ph.D. LL.D. Watkins
1888 CARROLL E. SMITH LL.D. - Syracuse
1890 PLINY T. SEXTON LL.D. Palmyra
1890 T. GUILFORD SMITH M.A. C.E. LL.D. - Buffalo

1893 LEWIS A. STIMSON B.A. LL.D. M.D. - New York
1895 ALBERT VANDER VEER M.A. Ph.D. M.D. - - Albany
1895 CHARLES R. SKINNER M.A. LL.D.

Superintendent of Public Instruction, ex officio

1897 CHESTER S. LORD M.A. LL.D. Brooklyn

1897 TIMOTHY L. WOODRUFF M.A. Lieutenant Governor, ex officio

1899 JOHN T. McDoNOUGH LL.B. LL.D. Secretary of State, ex officio

1900 THOMAS A. HENDRICK M.A. LL.D. - - Rochester

1901 BENJAMIN B. ODELL JR LL.D. Governor, ex officio

1901 ROBERT C. PRUYN M.A. - - Albany

1902 WILLIAM NOTTINGHAM M.A. Ph.D. Syracuse
One vacancy

SECRETARY

Elected by Regents

1900 JAMES RUSSELL PARSONS JR M.A. LL.D.

DIRECTORS OF DEPARTMENTS

1888 MELVIL DEWEY M.A. LL.D. State Library and Home Education
1890 JAMES RU.SSELL PARSONS JR M.A. LL.D.

Administrative, College and High School Depots
1890 FREDERICK J. H. MERRILL Ph.D. State Museum

PREFACE

During the prosecution of the study herewith given of a fauna
essentially new to the New York series of geologic formations, I have
been under special obligation to Professor Albert L. Arey, of Brooklyn,
the first to discover and record the presence of a Guelph fauna at
Rochester, for the use of his collections, of which many specimens are
here figured. In this place, also, I desire to make acknowledgment for
courtesies received from Colonel C. C. Grant of Hamilton Ont. This
work has, further, been essentially aided by the fine collections from the
tough dolomites at Shelby, made by D. D. Luther, who has also contributed

important stratigraphic details.

JOHN M. CLARKE

State Paleontologist

GUELPH FAUNA IN THE STATE OF NEW YORK

TV

INTRODUCTION

TYPICAL GUELPH DOLOMITES OF ONTARIO AND THEIR FAUNA
The Guelph formation of Canada has been regarded by geologists as
a local stratigraphic development succeeding the Niagara or Lockport
limestone and antedating the desiccation of the sea which precipitated the
deposits of the Salina stage. The formation in central Ontario, the region
of its typical and highest development, has the aspect of a great lentil
thinning to the southeast toward the Niagara river and to the northwest
at Manitoulin island in Lake Huron, in the interval attaining a thickness
of not less than 200 to 300 feet. Whether it is interrupted at this northern
point is not determined, but it has recently been shown that certain
characteristic fossils of the fauna occur in the territory of Keewatin about
James's bay (Equan river) ; Dr Whiteaves has described two species of
Trimerella from this region and these seem to indicate the presence of the
formation.1 The actual amount of deposit has however not been accurately
measured, and the exposed sections have for the most part proved to be
along the quite uniformly northwest strike of the strata. The entire
formation is quite completely dolomitized, and this pervading alteration,
together with the distinctly fragmental and sandy character of much of
the deposit, indicates substantial deviation from the static conditions under
which the normal Niagaran fauna was laid down. To the probable origin
of these dolomites attention will be directed in a later paragraph. The
fauna accompanying this formation has peculiarities of composition which
separate it from any earlier manifestation of the Upper Siluric or at least
from the Wenlockian fauna of the Niagaran (Rochester) shales and the
modified continuation of that fauna into the Lockport limestones of New
York.

It is striking for several of its peculiarities both positive and negative.
These may be itemized briefly: (i) The prevalence of holostomatous,
probably opercle-bearing gastropods of the genera Coelocaulis, Pycnom-

1 Ottawa Naturalist [Oct. 1902], p. 139.

GUELPH FAUNA IN THE STATE OF NEW YORK 5

phalus, Euomphalus and Polytropis (auct.} and of schizostomatous genera of
the style of Murchisonia, Pleurotomaria, Loxoplocus, etc. These are all
often of notable size and are more abundant individually and in species than
at any other Siluric date in American sections. (2) Abundance of cephalo-
pods of cyrtoceran genera, of Phragmoceras, Trochoceras, etc. (3) Pres-
ence and special life period of the heavy- shelled, edentulate brachiopods,
Monomerella, Trimerella and Rhinobolus_ (4) Immense abundance at
certain localities of the ponderous shelled clam Megalomus. (5) Paucity
of other lamellibranchs and of brachiopods, bryozoans and trilobites.
(6) Existence of corals and coral-making stromatoporoids, for the most
part in an incomplete and semimacerated condition. Their abundance in
the fauna is unquestionable, but their present condition is no true indica-
tion of their original state.

A fauna of such composition is distinctly late Siluric, at the same time
quite as distinctly unlike any other element of the Appalachian Siluric
sections.

The term Guelph, then, indicates both a faunistic and, in its typical
province, a lithologic element of distinctive significance in the Siluric suc-
cession. In no sense is it a late presentment of the Niagaran fauna as
expressed in the shale beds beneath the Lockport limestone. It is true
and natural that species of the preceding fauna should present themselves
in the Guelph congeries, and though this is not carried to great extent, yet
we may always expect to find therein some well known and widespread sur-
vivors of the lower fauna.

GUELPH FAUNA OF NEW YORK AND ITS STRATI-
GRAPHIC RELATIONS

Historical

During the construction of the Erie canal, 1817-25, the rock cut-
tings near Newark in Wayne county brought to light an impure light
colored dolomite. Some fossils were obtained from this rock by Dr G.
W. Boyd, assistant to Professor James Hall, geologist in charge of the

6 NEW YORK STATE MUSEUM

fourth district of the State, and this occurrence was first noted with wood-
cuts and names of the fossils in the final report on the geology of that
district [1843, p. 137']. As it was evident that the horizon of these few and
inconspicuous though significant species (Loxonema boydi, Avicula
triquetra, Euomphalus sulcatus, Orthoceras laeve, Atrypa,
Delthyris, Cornulites) was above that of the Niagaran fauna, known best
then, as now, from its development in the lower beds or Rochester shales,
though recognized as continuing into the overlying Lockport limestone,
Professor Hall regarded them as appertaining to the life of the Onondaga
Salt group — the Salina formation of present usage. A few years later
Professor Hall's attention was directed by Sir William Logan to the
profuse occurrence of similar fossils in dolomites at Guelph and Gait Ont.,
and in 1848 he visited these localities, collected freely, and, in 1852, he
described and illustrated a considerable number of species obtained by him
at that time." In regard to the stratigraphic position of the beds bearing
this fauna, he states his view as follows [p. 340] :

A simple inspection of the plates . . . will show that these fossils
are typical of a distinct period from that of the Niagara group, and, though
the few species yet known from the base of the Onondaga salt group in
New York seem scarcely sufficient to indicate a well marked period or to
claim positive identity in age with those of the Gait limestone, yet we are
compelled to regard them thus or to rank the latter as a group entirely
distinct from any yet recognized. . . Whether we regard them (the Gait
and New York fossils) as of the age of the Onondaga Salt group or not, we
know that they lie above the strata typified by the numerous fossils already
described as belonging to the Niagara group and strictly should form no
part of that group.

This opinion was expressed long before Robert Bell, now acting director
of the Canadian Geological Survey, proposed to distinguish the formation
in Ontario by the term Guelph; Hall's term "Gait limestone" being a
dangerous approach to the better known and older stratigraphic name,

•Professor Hall, in a subsequent reference to this discovery [N. Y. State Cab. Nat.
Hist. 20th an. Rep't. 1868. p. 305 (rev. ed. p. 347)] mentions the origin of the rock
exposure, though nothing is said of it in the fourth district report.

'Pal. N. Y. 2:341 et seq.

GUELPH FAUNA IN THE STATE OF NEW YORK /

" Gault." It is clear from the expressions above quoted that Hall was
the first to recognize the faunistic distinction of this association from the
Niagaran ; * but the discriminating observations of the Canadian geologists,
Logan, Bell and Murray, aided notably in elevating Guelph sedimentation
to the dignity of an event separable from the Niagaran. Professor Hall,
after extending his studies of the Upper Siluric dolomites over the area of
their distribution in Wisconsin, Illinois and Iowa, was inclined, in subse-
quent expressions, to caution in respect to the separation of Niagaran and
Guelph faunas ; 2 and to these we shall have occasion to refer in bringing
the data here presented into harmony with facts previously known.

The Wayne county, N. Y., locality for " Onondaga Salt group " fossils
was long ago lost. Nothing more is known of it than was given by Hall
in 1843 ; and no examination of the region in later years has given any
clue to exposures of this horizon, but some remarks on the horizon there
presented are given in a subsequent paragraph.

The Lockport or Niagaran dolomite in western New York makes a
very clearly defined topographic feature, specially where transected by
drainage ways. As is well known it is the rock which is the cap and occa-
sion of the falls at Niagara and of the upper falls of the Genesee river at
Rochester, and, though modifying the contour between these points, only
its lower parts project freely as exposure or lie under slight drift cover.
This mass of dolomites, which is not less than 100 feet in thickness
between Niagara Falls and Rochester, is at bottom at first comparatively
pure and hard, but becomes more and more dolomitic and less resistant3
toward the top. The overlying soft shales, gypsum beds and "platten"
limestones of the true Salina have been so worn down by obsequent
drainage that south of the Niagara escarpment, which is largely con-
stituted of only the lower layers of the Lockport dolomite series, the

1 See also Pal. N. Y. 1859. 3 : 30.

•N. Y. State Cab. Nat. Hist. 2oth Rep't. 1868. p. 306 (rev. ed. p. 348).
3 That is, more yielding to meteoric agency, because the purer the dolomite, in this
section, the more completely is it of fragmental origin.

8 NEW YORK STATE MUSEUM

ground is continuously low, much filled with detritus and specially swampy.
The northern reaches of the Oak Orchard swamp, extending from near
Churchville, Monroe co. on the east, across Orleans county, are excavated
in the Salina shales and have the dolomite series (Guelph and upper
Lockport) for a floor. Hence it is not altogether strange that, during the
years of geologic study which have elapsed since 1 843, extremely little has
been seen of the strata buried in this almost undissected region.

In 1892 Albert L. Arey brought to the attention of the geologic
section of the American Association for the Advancement of Science in
session in the city of Rochester, his discovery of a fine series of fossils
from this horizon at the top of the Lockport dolomites in and about that
city. Some of these were obtained from the uppermost layers in a quarry
then being worked in the southwest part of the city and known as the
Nellis quarry ; at present writing these workings are abandoned. More
were derived from occasional excavations for municipal improvements made
in the southern part of the city, affording an opportunity for collecting
which may sometime recur but which is beyond the control of the geologist.
This fauna was subsequently the subject of study by its discoverer, who
published a brief account of it in the Proceedings of the Rochester
Academy of Science [1892. 2 : 104-7],

These organisms proved to be for the most part preserved in nodules
of white chert, of which they have frequently formed the nuclei, but in
which more often they had become irregularly involved in the process of
segregation. The shells themselves are largely replacements in chalcedonic
silica and preserve with fine accuracy and in a manner altogether unusual
for paleozoic fossils the important exterior surface ornament. This mode
of preservation makes them extraordinarily interesting subjects. In the
brief paper cited Mr Arey has brought the fauna as then known to him
into comparison with the species of the Canadian Guelph and the published
lists of fossils from the Chicago and Racine limestones, and elicits there-
from the very close similarity in general composition of the Rochester and
Guelph faunas and the striking contrast between the former and the faunas

GUELPH FAUNA IN THE STATE OF NEW YORK 9

of the Rochester shale and Lockport limestone. The paper concluded with
a list of 15 species identified by the author as common to the Canadian
and Rochester Guelph.

It would be impracticable for any investigator to obtain access to these
species except by such personal consideration as that shown us by Mr Arey
who has availed himself of transitory opportunities not likely to return. As
the Nellis quarry is no longer productive, and the student can hardly wait
for possible further city excavations into this interesting horizon, we have
endeavored, with the important Arey collection as a nucleus, to further
exploit this interesting fauna throughout western New York.

The natural sections of the dolomite series in Monroe county are very
few, incomplete and unsatisfying. To the series of sections made as a
result of searching all the water courses and trenchings, we shall presently
refer ; as none of them expose the strata with which we are now con-
cerned, we can correlate them most satisfactorily after consideration of
the developments given in the following.

Section of the dolomites at Shelby, Orleans county

While zigzagging across the Niagara cuesta in 1901 in the search for
this Guelph horizon, the writers discovered a finely extended outcrop of the
dolomite series along Oak Orchard creek, from i to i^ miles south of
Shelby village, in Shelby, the southwestern township of Orleans county.
Oak Orchard creek, a few miles to the south of this place, receives the Erie
canal feeder or drainage channel from Oak Orchard swamp, and from that
point the artificial and natural water courses are combined. To effect
this function, the bed of the creek has been depressed by excavation of the
natural rock section to a depth of 8 to 10 feet, and an immense amount of
material thrown on the banks in most favorable situation for examination.
The stratigraphic section here stretches along the creek for about 2
miles, and has been briefly sketched in a previous publication.1
At the base of the falls at Shelby are

1 N. Y. State Paleontol. Rep't 1901, p. 521.

JO NEW YORK STATE MUSEUM

1 An exposure of normal Rochester shales, above which lie

2 Sixty feet of hard, dark gray dolomites, full of small cavities bearing
druses of dolomite and calcite, but with few or no fossils ; only parts of this
series are exposed (Lockport limestone) ;

3 Two feet of porous dolomite, the cavities being vermicular or having
the aspect of small tubes (Lockport limestone) ;

4 Three feet of dark gray dolomite. This is the lower Guelph bed. It
contains a fairly profuse fauna, of which Trematonotus alpheus is
the leading element, but Monomorella noveboracum the more
exclusive species (Monomorella bed). Both are highly abundant and
occur in extraordinarily fine specimens. Of other species the stratum
contains : Poleumita crenulata, Coelidium macrospira,
Lophospira bispiralis, Cyrtoceras orodes, Poteri-
oceras sauridens, Protophragmoceras patronus, Tro-
choceras desplainense, T. costatum, etc. ;

5 Eight feet of gray dolomite with few fossils, and these characterizing
the Lockport fauna : Zaphrentisbilateralis, Enterolasma c a 1 i -
culus, Stropheodonta profunda, Orthothetes subplanus
and a few others. This mass is capped by a thin bed of shaly limestone
containing a profusion of small fossils, among which are: Cladopora
multipora, Halysites catenularius, Lichenalia concen-
tric a, Dalmanella elegantula, Orthothetes subplanus,
Leptaena rhomboidalis, Camarotoechia neglect a, Rhyn-
chotreta cuneata americana, W h i t f ie 1 d el 1 a nitida
oblata, Spirifer crispus (typical Rochester shale form), Cor-
nulites arcuatus, Dalmanites sp., Calymmene cf. niaga-
rensis, Proetus sp. This association is characteristic of the Rochester
shale and lower Lockport limestone. Over this bed lies a thin layer of
chert nodules without fossils.

6 Twenty-four feet of similar dark gray dolomite with fossils extremely
rare and of the same character as those below (Lockport limestone).

7 Eight to 10 feet of gray dolomite, bearing white chert nodules most

GUELPH FAUNA IN THE STATE OF NEW YORK I I

abundant in the lower part and containing inter alia, Trochoceras
desplainense, Orthoceras trusitum, Coelidium macro-
spira, Trochonema cf. fatuum, Trematonotus alpheus,
Cornulites arcuatus, Poleumita scamnata, P. sulcata,
Eotomaria galtensis, Spirifer crispus, Leptaena rhom-
boidalis, Pterinea subplana, P. undata, Stromatopora
galtensis, Diaphorostoma nia g a rense, Calymmene niaga-
rensis, Proetus sp. This we shall term the upper Guelph bed, and
shall have occasion to observe that its fauna is more nearly parallel to that
at Rochester than the lower or earlier appearance of the Guelph in this
section.

This is the southernmost exposure on Oak Orchard creek ; and it
appears that in the general planing of the country by ice and water any
harder beds above would have in some degree at least, resisted erosion and
left some trace of themselves in the well channeled way of this stream to
the south.

It seems fair to conclude, therefore, from this section supplemented by
similar evidence in Monroe county, that overlying beds, with the possible
exception of a few feet of dolomite, were the soft shales and thin "platten"
limestones of the Salina, and hence that the upper Guelph horizon, litho-
logically, topographically and faunistically here terminates the dolomite
period.

This section is represented in the following diagram.

12

Top of section

8-10'
24'

8'
3'

2'
60'

7

6

5

4

3 "|

2

2

I

NEW YORK STATE MUSEUM

Guelph fauna ; upper Shelby dolomite

>- Lockport dolomites

Guelph fauna ; lower Shelby dolomite

> Lockport dolomites, largely covered

Rochester shale

A significant feature of this occurrence is the double appearance of the
Guelph fauna. Its earlier manifestation is after the lapse of 63 feet of
Lockport dolomite; it retreated and reappeared after 32 feet more of these
Lockport dolomites with their characteristic species, had been deposited.
Here it closes the dolomite episode, and the Lockport species have finally
withdrawn. We designate these appearances of the fauna as the lower and
upper Guelph faunas or, as the local development of the fauna is predi-
cable and carries an impress of distinctive nature, as the lower and upper

GUELPH FAUNA IN THE STATE OF NEW YORK 13

Shelby faunas, contained in the lower and upper Shelby dolomites. It is
furthermore specially noteworthy that of these two manifestations of the
fauna, the lower is the purer Guelph, that is, is freer from complications
with species occurring in the Lockport dolomites. In the upper bed, how-
ever, the presence of such Lockport species is much more pronounced. On
the other hand, the intervening Lockport dolomites are wholly free from
any evidences of the Guelph species ; though decidedly meager in fossils,
yet these are all proper to the horizon in which they occur. Thus the over-
lapping faunas are relatively free of complication and intermixture. We
note again, as just stated above, that it is not the lower and purer Guelph
congeries that appears in the Rochester section ; on the other hand, it is
the later association, containing a number of Lockport limestone species,
that agrees better in composition with this more eastern development.

We are thus presented with conclusive evidence of an invasion of the
Guelph fauna from the west into western New York, while the Lockport
dolomites were being deposited and at about the middle of the period of
their formation ; this immigration was of brief duration, failed to acquire a
lasting foothold, withdrew without reaching far if at all east of Orleans
county ; it thereafter returned with some unimportant modification in com-
position, penetrated as far east as Monroe and Wayne counties, while the
previous occupant of the field withdrew, not to return.

At the close of the descriptions of the New York Guelph species we
have given tables showing the distribution of the fossils and bringing out
the difference in the composition of the early and late appearance of the
fauna in the Oak Orchard creek section and the relation of these manifesta-
tions to the fauna in Monroe county. For that place we reserve all further
discussion of the affinities of the congeries to extralimital expressions of the

Guelph fauna.

Niagara county

The rock exposures at Niagara Falls show 120 feet of limestone and
dolomite currently referred to the Niagaran formation. We have been
unable to determine the existence of the Guelph fauna in the vertical sec-

NEW YORK STATE MUSEUM

tion here afforded, though the unfavorable exposure may still veil its
presence, but we are satisfied that the careful analysis of this section
recently made by Mr Luther locates with precision the horizon which at
Shelby so much more favorably expresses its contents. To elucidate these
stratigraphic relations we here give the detailed section of the dolomites
presented in the cut of the Gorge Railway, yz mile north of the east end of
the bridge, supplemented at the top by a temporary exposure made by the
Ontario Power Co. on the Canada side.

Brown dolomites exposed at Goat island and Three Sisters islands
with summit near head of rapids. Full of cavities and with
Stromatopora, Halysites. Weathers very scraggy. Uppermost
bed (4') sandy

Car barn of Gorge Railway ; not exposed

Brown, thin bedded dolomites with rough surface and black partings
Thin bedded dolomite, fine grained and very hard. Continuous bed
of chert nodules near top ; probable horizon of upper Shelby fauna

25'

10'

8'

1 2' 6"

19'

1/6"

28'

Compact drab dolomite; few cavities. Horizon of lower Shelby
dolomite near top

Smooth, thin bedded dolomites with Stromatopora ; at top, Enter-
olasma, Favosites

Compact light brown dolomite

Rochester shale

The basal layer of the series (i) is quite homogeneous, though the
lower part is schistose. The same stratum is seen at Lockport along the
banks of the canal beginning a little west of the locks in the city and
extending continuously toward the southwest for a mile. Farther west
near Gasport it is quarried at the top of the banks of the ravine south of

GUELPH FAUNA IN THE STATE OF NEW YORK 15

the village and in a ravine south of Middleport. The layer may be differ-
entiated at the falls in Oak Orchard creek.

Stratum 2 is composed of varying proportions of hard, dark gray, sub-
crystalline limestone and irregular beds of unstratified bluish hydraulic
material, giving the whole a dappled appearance. It is dark blue when
fresh but weathers a very light gray. It is also known in the canal south
of Lockport and in the creek 2^ miles-southwest of Gasport. Stroma-
toporas are common in it. The horizon can be recognized at Shelby from
the piles of material just west of the village.

Stratum 3 is a compact, light brown dolomite of uniform texture. At
Niagara Falls there are small corals (Enterolasma caliculus, Favo-
sites) in the lower part. From the character of the rock and that of the
overlying stratum we regard this as the horizon of the lower Guelph fossils
at Shelby. There the subdivision into separate beds is more pronounced
and the fossils are restricted to a 3 foot layer ; this subdivision of the
stratum is also shown at Lockport where the layer is the highest and most
southern one exposed on the canal.

Stratum 4 is finer, harder and lighter colored than the layers above and
below and is filled with cavities. Near the top is a continuous row of chert
nodules which are bluish when fresh but become white on long exposure.
This layer is nearly in a plane with the crest of the American and Horse-
shoe falls. Fossils are extremely scarce but the exposure is unfavorable for
examination. Poleumita scamnata occurs here, a species not else-
where found except in the chert nodules of the upper Shelby and Rochester
horizon. This fact indicates that this chert layer represents the upper
Giielph horizon which would, thus, be separated from the lower horizon by
an interval of 20-25 feet, considerably less than at Shelby.

Above stratum 5, consisting of brownish dolomites in thin layers hav-
ing black partings, there is a covered interval of 10 feet (6), which is fol-
lowed by a 25 foot mass (7) of rough geodiferous dolomite in thick and
thin layers. This is exposed in the cut of the Gorge road south of the car
barn, at the south of Goat island and on the Three Sisters. This rock

1 6 NEW YORK STATE MUSEUM

contains numerous fossils ; Stromatopora, Halysites, Favosites (diffusely
branching form) Spirifer crispus, Trematospira (which is common
in the Guelph of Iowa), Coelidium macrospira, Pterinae
s u b p 1 a n a.1

The association indicates a mixture of Lockport and Guelph species,
though there is nothing in it which militates against its construction as a
Guelph fauna, as, in fact, a facies of the fauna somewhat removed in space
from the reefs about which the true Guelph was centered. We may note
that Professor Hall * described and figured specimens from "limestone below
the cliff at Niagara Falls "- — evidently loose — as Cyrtoceras? subcan-
c e 1 1 a t u m and Gomphoceras? sp. Both are identified with specimens
from the Rochester shale but this identification seems erroneous in the for-
mer and dubious in the latter case. These fossils are quite distinctly of
Guelph habit and it is probable that both were derived from this upper
layer. We may properly regard the layer of chert nodules below as pre-
senting the first appearance of the Guelph (i. e. the upper) fauna in this
section and in this case may conceive the thickness of 45 feet of dolomite
above this layer as imperfectly or not at all represented at Shelby.

The actual measurement of the dolomite section at Niagara Falls is 13
feet more than on Oak Orchard creek and this difference is largely if not
wholly at the top of the former. It is not now possible to say how much of
the section has been planed off in either place or what part of the difference
is to be ascribed to the thinning of the formation eastward. That a portion
of the top of the section throughout this region is concealed, is indicated by
borings. Deep wells in the Niagara region are stated to show about 100
feet of limestones above the exposure,3 but it is altogether uncertain that
this is to be accepted as correct or what part of such alleged increase can be
ascribed to the dolomite series.

1 These fossils have been chiefly collected on Goat island by Gilbert van Ingen.

3 Pal. N. Y. 2: 290, pi. 61.

sGrabau. N. Y. State Mus. Bui. 45, p. 114.

GUELPH FAUNA IN THE STATE OF NEW YORK 17

Other manifestations in Orleans county

In the townships of Barre and Clarendon lying between Shelby town-
ship and the west boundary of Monroe county, outcrops of the dolomites
are seldom shown. Except at Clarendon village almost the entire surface
of the dolomites has been planed down and forms the floor of the basin in
which lie detached northern parts of the Oak Orchard swamp. The lower
element of the series is exposed at several places near the northeast corner
of Barre. At Clarendon village the exposure shows the lowest layers (i,
of the Niagara section) in and above the falls ; in the ridge south of the
village strata 2 and 3 are exposed. No trace, however, of Guelph fossils
has appeared here. About 40 feet above the base of the dolomites
there appears a cherty layer, similar to, perhaps identical with that in
Niagara county; in the latter section the elevation of the layer above the
Rochester shale is 75 feet.

One and one half miles east of Barre Center and on the ridge south
of Clarendon are found the rough layers appertaining to division 7 of the
Niagara section, and the more even grained, sandy dolomites which cap
the section near the rapids of the Niagara river, are quarried at Honest
Hill, 3 miles south of Clarendon.

In all the section exposed at Clarendon no trace has been found of
Guelph fossils ; the lower Guelph fauna as expressed at Shelby is absent
and the horizon of the upper fauna is not clearly exposed. South of the
line of outcrop of these upper rough dolomites the country is dotted with
boulders of this origin, made rougher and more jagged by the action of
decomposing agencies.

Monroe county

Allen creek section. Directly south of Rochester, an interrupted sec-
tion of the dolomites is made by Allen creek, a stream of many branches,
traversing the town of Pittsford, flowing north and discharging into the
Irondequoit river, (i) The lowest exposure is beneath the large cul-
vert through which the stream passes under the New York Central Rail-

NEW YORK STATE MUSEUM

road (Direct road), where 20 feet of rough dolomites are shown. The
bottom of this exposure is 350 feet A.T. After a covered interval esti-
mated at about 10 feet, another exposure (2) is seen at Lincoln's Mills,
near the crossing of the East avenue road ; 25 feet of dark bluish gray
dolomite, with drusy cavities and showing specimens of Stropheodonta
profunda, are exposed. Estimating a covered interval of 20 feet, a third
outcrop (3) occurs on the premises of John Balder, consisting of 5 feet of
evenly bedded dolomites overlain by 8 to 10 feet of darker rock with
Stromatopora. Above are 2 feet of a peculiarly concretionary layer with
many corals of the Lockport limestone and similar to a layer in the Pike
quarry section, Rochester. Continuous with this exposure, farther up the
creek are (4) 10 feet of dark dolomite with corals; 5 feet of finer, harder
and thin bedded rock; 12 feet of dark brown dolomite with Stromatopora,
Halysites and Favosites. The summit of the outcrop is about 8 rods east
of the Erie canal. Above this section is a covered interval estimated at
about 15 feet, and herein probably lies the Guelph horizon of the Nellis
quarry, which, as we shall presently note, is above the dolomites in
Pike quarry. The exposure next following on the stream (5) is 5 to 6
rods long in the low banks and covers about 8 feet of thin " platten " lime-
stones of the Salina. In the bottom of the Erie canal, 2 miles north-
west of Pittsford, 470 feet A. T., and ^ of a mile from the last named
exposure are black shales with interbedded gray " platten " limestones
abounding in Salina crustaceans. Exposure 5 has an elevation at the
bottom of 485 feet and hence lies above the Salina shales referred to.
We may fairly conclude that these Salina black shales lie immediately
above the covered Guelph horizon.

The total thickness of the dolomites here according to the section
given, is about 1 20 feet.

Brighton. At a rock cut, i mile east of Brighton on the Direct road
(New York Central Railroad) are 1 5 feet of brown dolomites with Stroma-
topora and Favosites. The exact horizon of this layer in the Lockport
dolomites is not altogether clear.

GUELPH FAUNA IN THE STATE OF NEW YORK 1 9

Rochester and vicinity : Pike quarry, Frost avenue and Summer street.
The section where best exposed is as follows, beginning at the bottom,
which is the surface of the water in the quarry :

1 Brownish gray to black scraggy dolomite with drusy cavities.

Stromatopora and Favosites abundant. (See Allen creek sec-
tion, no. 4) - 2 feet

2 Compact unbroken dolomite - 5 "

3 Dark brown dolomite like i - 3 "

4 Dark bluish gray dolomite, weathering brown ; compact - 10 "

5 Brown sandy dolomite in layers 2 to 4 inches thick. Heavier

layer at top. Stromatopora and Zaphrentisbilateralis 6 "

This section is clearly all of Lockport dolomite.

Nellis quarry, McLean street. The highest part of this locality is
1 200 feet west and 600 feet south of Pike quarry, and this rock section
runs 15 feet higher than in that section. The white chert nodules from
which Mr Arey obtained many of the Guelph species before workings
here were abandoned, are all in the upper part of this additional
thickness.

The rapids, Genesee river. The exposure here is 25 or 30 rods long
and includes about the same section as Pike quarry. The Guelph horizon
with white chert is not exposed.

Lauer guarry, town of Gates, 2 miles west of the Rochester city line.
The lower part of the section exposes 15 feet of dolomite with Favosites,
Stromatopora and Enterolasma caliculus (Lockport). The high-
est part of the quarry gives 3 feet additional, which may rise to the Guelph
horizon, but no satisfactory evidence is at hand. The elevation here is 550
feet A. T. The quarry is not now operated.

Newman quarry, \ % miles north of Lauer quarry and 3 miles west of
Rochester city line; town of Gates; 30 to 35 feet above the preceding.
At the south end of the quarry the section is from the bottom.

2O NEW YORK STATE MUSEUM

1 Compact bluish dolomite, with Enterolasma caliculus

(Lockport) 4 feet

2 Dark grayish brown dolomite with white chert nodules. This

layer has furnished Trematonotus alpheus, but fossils
are very scarce. (Guelph or upper Shelby horizon)

Wayne county

The original occurrence of Guelph fossils in New York, was, as we
have already noted, from the bottom of the Erie canal near Newark. Pro-
fessor Hall has stated that these remains (a mere handful of depauperated
shells) were thrown out with the Salina marls, the rock containing the fossils
preserving " the celluliferous structure and characteristic color of the argila-
ceous limestone of that formation." ' Newark lies on the Salina shales which
are shown to a depth of not less than 200 feet in well sections in the city.2
The canal (9 feet deep) passes through the city in an east-west course which
it retains for several miles. The nearest outcrop of the dolomite is at Fair-
ville, 6 miles due north. This outcrop may be near the middle of the series
and the dip of the beds is south 30-50 feet to the mile. It would thus
appear that Professor Hall's specimens must have come from a high hori-
zon, even within the Salina shales wherein was represented a brief, ill con-
ditioned return of Guelph species.

Southern Ontario — the section at Hamilton

The composition of the Niagara escarpment, which is finely continued
along Lake Ontario (Hamilton bay) just south of the city of Hamilton, has
been carefully studied by Colonel C. C. Grant of that place, who has pub-
lished various data in regard to it. Dr J. W. Spencer also some years ago
studied this region stratigraphically and described some of the fossils there-
from. From these sources we gather that the section here is the following,
beginning at the top.

*N. Y. State Cab. Nat. Hist. 2oth An. Rep't, p. 305 (rev. ed. p. 347).

"The section of a well put down at Alloway, 3 miles south of Newark, showed 580 feet
of Salina shales to the top of the dolomites. [See Prosser. Am. Geologist, June 1900,
P- 353]

GUELPH FAUNA IN THE STATE OF NEW YORK 21

1 The Barton beds (Spencer). Summit formation,

mostly dark dolomite with interbedded shale and
soft hydraulic layers, the latter considerably
employed in the manufacture of cement - - 87 feet

2 Magnesian silicious beds filled with irregular

nodules of light or white chert - - 20 feet maximum

3 Blue dolomite - 5-6 feet

4 Rochester shale - 1 7. 6 feet

For our immediate use we need not carry the section further down,
though the outcrop of the cuesta extends well into the Medina, as on the
Niagara river. To return to i : these heterogeneous strata, consisting of
shales, soft waterlimes and hard dolomites (Barton beds1) contain discrete
faunas. In the hydraulic layers are Atrypa reticularis, Enter o-
lasma caliculus, while the dark dolomites bear a distinct association.
With the aid of Colonel Grant and by the study of his collection and that
of the Hamilton Scientific Association, we are able to cite these as charac-
teristic species : Orthothetes subplanus, Leptaena rhomboi-
dalis, Orthoceras bartonense Spencer, a Dawsonoceras identical
with D. annulatum. More important however are the following, each
of which has been seen by Colonel Grant in but a single specimen : P 1 e u-
rotomaria perlata,* Coelidium macrospira, Trochoceras like
T. waldronense from the Waldron. The first two of these are
of distinctively Guelph character, and P. perlata has not been found
outside of that fauna. Colonel Grant finds that the upper layer of these
Barton beds, whenever stripped of soil, is everywhere deeply scored
by glacial shearing and believes that some part of the dolomites has
been thus carried away. Hence we get in these Barton beds, a clue
to or suggestion of the true Guelph fauna, which we may well believe

•The employment of this term, so well known and long established in the English
Tertiary nomenclature, recalls how nearly Professor Hall came to duplicating the same
English nomenclature by introducing the terms Gait and Ludlowville.

1 It is apparently this species that has been described by Spencer as P. clipeiformis
from this upper horizon at Hamilton. [Univ. Mo. Bui. i. 1884. p. 57, pi. 7, fig. 6]

22 NEW YORK STATE MUSEUM

was more fully developed in the later deposits removed by glacial

erosion.

Summary

We may briefly summarize the evidence from these sections thus :

The more prolific development of the Guelph fauna in the lower
Shelby dolomite on Oak Orchard creek does not extend so far eastward as
Monroe county and has as yet been observed only at the original locality.

The Guelph fauna of the upper Shelby dolomite, which is largely
involved in chert nodules, appears under similar conditions both at Shelby,
about Rochester, and in the Niagara Falls section.

It is to be noted that, while the white chert segregations are in some
measure an index of the upper Guelph horizon, those which contain fossils
have proved to be in an exceedingly small ratio to the number present.
The experience of Mr Arey in the exposures about Rochester showed that
these fossils were to be had only by very great diligence and watchfulness,
and it seems probable that they will always be of rarity. The dolomite
containing these silicious nodules weathers freely to sand, retreating from
about the nodules, which thus become loosened and set free, so that the
rough, scraggy dolomitic blocks with which the surface of the country is
freely covered, specially in the towns of Ogden and Sweden, Monroe co.,
seem to us to be in part at least derived from this upper Guelph horizon.

We conclude that the episode of the Lockport dolomites, which was
virtually the closing sedimentation phase of the true marine Siluric, embraces
representations of two quite distinct faunas ; (i) the essential or normal fauna
of the time and place, the immediate successor of, and derivative from the pro-
fuse Rochester shale (Niagaran) fauna, that is to say, the peculiar and appro-
priate fauna of the Lockport stage ; (2) at least two, perhaps three manifes-
tations of the typical Guelph fauna which has entered this province from the
west. These are embedded in the dolomites and interbedded with the layers
containing the other fauna. They represent a distinct organic facie's from
the other, and the relations of both are those of mutually encroaching
faunas of adjoining provinces without alteration of sediment and sea.

In New York, therefore, both Lockport and Guelph faunas pertain to
the period of the Lockport-Shelby dolomites.

GUELPH FAUNA IN THE STATE OF NEW YORK 23

FAUNA OF THE GUELPH DOLOMITE IN WESTERN

NEW YORK

ANTHOZOA

TETRACORALLA (HEXACORALLA?)

ZAFHBENTIS Rafinesque. 1820
Zaphrentis cf. racinensis Whitfield

Plate i, fig. 2, 3

Cf. Zaphrentis racinensis Whitfield, Geology of Wisconsin. 1882. 4:277,
pi. 14, fig. i, 2

Four casts of the interior of the calyx of a supposedly turbinate coral
were found among the Rochester material, one of which had been identified
by Mr Arey with Zaphrentis racinensis. We have a few speci-
mens also from the upper horizon at Shelby. Professor Whiteaves records1
that he had corals from various Canadian localities in a similarly poor state
of preservation, and these he regarded as possibly identical with Z. raci-
nensis Whitf. That species itself was founded on internal casts of cups
only, from the Racine limestone, and, while our specimens show the same
number of septal impressions as those and also agree therewith in the
development of the septal fossette and the mode of contraction of the cali-
cular cavity, they uniformly attain only about half the size ofZ. racinen-
s i s, the latter having a calyx twice as deep as that from Rochester.
While it would be hazardous to identify these corals from such casts only,
dissimilarity in size does not impugn their usefulness for correlation. It is
not probable that the casts represent specimens of Z. (P o 1 y d i 1 a s m a)
turbinata Hall,2 from the Lockport limestone of New York, as that
species is characterized by the duplication of its septa about the outer walls
and the abrupt depression of the cup about half way from the outer margin
to the center, which would give to the casts a cylindric interior and a saucer-
shaped superior part.

*Op. fit. 1895. p. 49.

3 Pal. N. Y. 1852. 2: 112, pi. $?, fig. za-h.

24

NEW YORK STATE MUSEUM

In the upper Guelph of Shelby was collected a single specimen which
possesses a rapidly widening corallum, narrow, thin septa and a deep cup ;
on account of these characters, it has also been referred to Z a p h.
racinensis rather than to Zaph. turbinata.

KNTKROLASMA Simpson, i goo
Enterolasma cf. caliculus Hall (sp.)

Plate i, fig. i

Streptelasma calicula Hall, Paleontology of New York. 1852. 2: in, pi. 32,
fig. xa-k

Of somewhat more frequent occurrence than the foregoing in the Guelph
at Rochester are casts of a smaller turbinate, rapidly expanding zaphrentid,
slightly curved toward the apex. These in exterior appearance suggest
identity with Streptelasma caliculus Hall. Unfortunately in
nearly all specimens the internal structure has been destroyed by dolomitiza-
tion, but a single specimen has afforded in thin section, evidence of a pseudo-
lamella consisting of the involved vermiform projections of the septa sug-
gesting the convolutions of the intestines. Simpson * has united under
the generic name Enterolasma, species presenting this peculiar divergence
from the structure of Streptelasma, assuming the S. strictum Hall, of
the Helderbergian, as the type of the genus. Two other species of Niaga-
ran age have been referred by this author to the genus, viz P e t r a i a
waynensis Safford and Streptelasma radicans Hall, the former
from Perry county, Tenn., the latter from Waldron Ind. Enterolasma
waynense differs from E. caliculus in the coarser and more promi-
nent costae and the sharper concentric striae. It is also proportionally
more slender. These are but slight differences, which are not pronounced
in the Guelph species. Enterolasma radicans has a more irregular
growth and a broad base of attachment.

This characteristic dwarfed coral has not been observed in either the
lower or upper Guelph beds at Oak Orchard creek, while it was found to be

'N. Y. State Mus. Bui. 39. 1900.

GUELPH FAUNA IN THE STATE OF NEW YORK 25

abundant in the dark crystalline limestone directly underlying the upper
Guelph chert nodules.

DIPLOPHYU.ITM Hall. 1852
Diplophyllum caespitosum Hall

Diplophyllum caespitosum Hall, Paleontology of New York. 1852. 2:115,
pi. 33, fig. xa-r

Cyathophyllum pelagicum Billings, Geol. Sur. Canada. Paleozoic Fossils.
1862. i: 108; Catalogue of the Silurian Fossils of Anticosti. 1866. p. 34

Diphyphyllum caespitosum Nicholson, Paleontology of the Province of
Ontario. 1875. p. 59

Diphyphyllum caespitosum Lambe, Ottawa Naturalist. 1 899. 1 2 : 240

Diphyphyllum caespitosum, Geol. Sur. Canada. Contrib. Canadian Paleon-
tology. 1901. v. 4, pt 2, p. 158

Several fragments of coral stocks from Rochester show aggregate
simple, cylindric coralla of somewhat varying diameter. Most of these
coralla are so weathered or dolomitized that the interior structure is lost ;
one stock which was better preserved, afforded sections showing that
the coral has the internal structure described by Hall for the Niagaran
species D. caespitosum, viz a deep calyx ; below this an internal zone
with tabulae and septa, and a wide marginal zone with septa and numerous
dissepiments, which give this zone a cellular appearance. In mode of
growth also this form agrees with D. caespitosum. It is not common
in the chert nodules of the Guelph horizon.

Observations. The generic relations of this species have been vari-
ously interpreted by different writers. Hall erected for it the genus
Diplophyllum, citing as differentials the characters of the distinctly sepa-
rated central and marginal areas of the cell, and mentioned its apparent
relationship to Diphyphyllum Lonsdale, without stating the differences
between the two. Latterly, Diplophyllum has been considered a synonym
of Diphyphyllum ; and Rominger,1 who has been followed by Lambe, united
under Diphyphyllum both Eridophyllum and Diplophyllum, because of

1 Geol. Sur. Michigan. 1876. 3:120.

26 NEW YORK STATE MUSEUM

similarity in mode of growth, admitting however three different modifica-
tions in their structure. In the first of these, consisting exclusively of Siluric
forms, the demarcation of the outer and inner area is very obscure, and the
septa reach to the center of the cells ; in the second the septa are confined
to a narrow outer zone, and the zones are not separated by an intermediate
wall ; and the third has a distinct secondary wall separating the inner and
outer zones, and this the septa never transgress. Diplophyllum caes-
p i t o s u m, by the development of the septa which reach the center, falls
under the first group ; the second is that comprised under the generic term
Diphyphyllum ; and the third is equivalent to Eridophyllum. The last two
genera have usually been recognized by European writers, and Freeh has
stated that Diphyphyllum was based on corals of the Carboniferous lime-
stone, quite distinct from Eridophyllum, and a question may therefore arise
as to the propriety of employing the term Diphyphyllum so as to include
Diplophyllum.

Diphyphyllum has been considerably misunderstood. Edwards and
Haime1 united it with Lithostrotion, at the same time creating the similar
genus Eridophyllum, which on account of its internal wall was compared
with Acervularia. De Koninck and Dybowski, however, later defined the
genus Diphyphyllum as characterized by the presence of an internal wall
with regular tabulae within it and by the feeble development of the septa.
The group defined by these characters is identical with Rominger's second
modification except that this author describes this group as without internal
wall. Other writers on Diphyphyllum contend that the internal wall is
never but slightly developed. Freeh 2 states that, on account of the inter-
nal walls in Diplophyllum caespitosum, Hall's comparison of that
species with Diphyphyllum was erroneous, and that it is much more nearly
related to Acervularia. It is also distinctly stated that the septa in Diphy-
phyllum are feebly developed, while in Diplophyllum they are quite strong
and reach the center.

'Polyp. Foss. Terr. Paleoz. 1851. p. 446.
2 Lethaea Palaeozoica, i : 350.

GUELPH FAUNA IN THE STATE OF NEW YORK 2J

Mr Lambe, who has undertaken a revision of the Canadian corals,
united Diplophyllum and Eridophyllum under Diphyphyllum, which is
characterized as possessing no "inner wall"; and Diplophyllum
caespitosum is said to have " dissepiments arching upward, between the
septa, against the outside wall, generally in a single series, their outer edges,
as seen in transverse section, assuming the appearance of an inner wall
situate less than i mm from the wall proper." This appears to us to con-
firm the presence of an inner wall in D. caespitosum, as the inner wall
of the other genera, where it can be said to be typically developed, such as
Lonsdaleia and Acervularia, consists also of a single or terminal series of
strongly developed upward arching dissepiments. We must, therefore, as
long as the term " inner wall " is used loosely, consider D. caespitosum
as possessing this structure. It would seem to us that the term should be
restricted to that inner wall which is often formed by the lateral thickening
of the septa, in like manner as the pseudotheca.

From sections of Diplophyllum caespitosum, of Erido-
phyllum verneuilianum, the type species of that genus, and of
E. simcoense, given by Lambe in the paper above cited, it becomes
apparent that the internal wall of Eridophyllum, or walls (for in E. ver-
neuilianum occur two series of dissepiments) are also constructed as
in Diplophyllum, and that the difference between the two genera can at
present be based only on the different development of the septa, while the
difference assumed to consist in the failure of the septa to transgress beyond
the inner wall in Eridophyllum is not valid. To this difference may be
added the presence of the characteristic radiciform expansions in Erido-
phyllum. Diphyphyllum differs from the two latter genera by its very
feebly developed septa, which do not reach the internal wall, and by its
different geologic range. While these distinctions in the three genera may
be only of degree, the groups denoted by them differ also in geologic age,
Eridophyllum being essentially a Devonic and Diphyphyllum entirely a
Carbonic genus.

Diphyphyllum caespitosum occurs, according to Billings, as

28 NEW YORK STATE MUSEUM

early as the Anticosti group of Anticosti ; it is common in the Lockport
dolomite of New York, and is reported from the same horizon in Ontario
(Thorold) ; in Wisconsin it ranges from the Mayville beds, through the
coral and Racine beds into the Guelph horizon.

HBLIOPHTIXUM Hall. 1849

Heliophyllum sp. indet.

Plate 1, fig. 4, 5.

A single internal cast of a small calyx found in the Guelph of Roches-
ter shows distinctly the impression of the denticulations on the septa, which
in the present state of our knowledge are regarded as characteristic of
Heliophyllum. Though a considerable number of Siluric species have been
referred to this genus, the specimen in hand is not sufficiently complete for
identification.

TABULATA

FAVOSITES Lamarck. 1816

Coral stocks of Favosites belong to the most common fossils of the
Guelph dolomite. The different coralla show considerable variation, indi-
cating the presence of several species.

Favosites niagarensis Hall

Favosites niagarensis Hall, Paleontology of New York. 1852. 2:125, pi.

34A bis, fig. 4a-h
Favosites gothlandica Whiteaves (in part), Paleozoic Fossils. 1895. v. 3,

pt 2, p. 50
Favosites niagarensis Lambe, Contrib. Canadian Paleontology. 1 899. v. 4,

pt i, p. 71

This is one of the commonest of the species in the white chert nodules
at Rochester and the upper Guelph of Oak Orchard creek. The specimens
are for the most part subspheric, attain the size of the fist and are composed
of corallites which are seldom larger than 2 mm in diameter, and average
considerably less, specially in immature growth. The tabulae are regular
and flat, but vary in the intervals between them in different specimens, from
.3 mm in one to 1.5 mm. On account of the incrustation of thickened walls,

GUELPH FAUNA IN THE STATE OF NEW YORK

29

the pores and spines can rarely be observed ; one was found to possess two
rows of alternating pores on the sides. The presence of numerous spines
is indicated by pits on the internal casts of cells. These spines are arranged
in three or four rows corresponding to as many septa on each side.

It is safe to consider forms with these characters as identical with F.
niagarensis.

Observations. Whiteaves,1 in his description of Favosites goth-
1 a n d i c u s from the Guelph at Gait, Hespeler, Elora and Fergus, regards
Favosites niagarensis Hall as a synonym of that species, but
remarks that there are no examples of the typical form ofF. gothlandicus
with large corallites, among the Guelph organisms of the survey museum,
and that he has seen but a single specimen thereto. On the other hand
Mr Lambe, in the Revision of the Madreporaria Perforata and the
Alcyonaria* describes F. niagarensis and F. gothlandicus sepa-
rately, but only F. g o t h 1 a n d i c us as occurring in the Guelph of Ontario.
Milne-Edwards and Haime also regard F. niagarensis as synonymous
with F. gothlandicus, but at the same time give a diameter for the coral-
lites which is greater than that of the Guelph specimens. Hall expressly
stated that his species was distinguished by the size of the cells, and also
usually formed small spheroidal masses, characters with which these Guelph
specimens are in accord.

Favosites hisingeri Edwards & Haime

Favosites hisingeri Milne-Edwards & Haime, Polypiers Fossiles des Terr.

Paleoz. 1851. p. 240, pi. 17, fig. 23., 2b
Astrocerium venustum Hall, Paleontology of New York. ^B^x. 2:120,

pi. 34, fig. la-j
Astrocerium parasiticum Hall, Paleontology of New York. 1852. 2:122,

pi. 34, fig. 2a-i
Astrocerium pyriforme Hall, Paleontology of New York. 1852. 2:123,

pi. 34A, fig. la-e

1 Paleozoic Fossils, v. 3, pt 2.

a Contrib. Canadian Pal. v. 4, pt i, p. 7.

30 NEW YORK STATE MUSEUM

Favosites venusta Nicholson, Paleontology Prov. of Ontario. 1875. P- 65.
Favosites venustus Rominger, Geol. Sur. Michigan. Fossil Corals. 1876.

p. 22, pi. 5, fig. 3
Astrocerium venustum Whitfield, Geology of Wisconsin. 1882. 4:270,

pi. 13, fig. 8-10

Favosites hisingeri Whiteaves, Paleozoic Fossils. 1882. v. 3, pt 2, p. 51
Several specimens from the dolomite at Rochester and the upper
Guelph at Oak Orchard creek differ materially from other species in size of
the corallites, and, while they are uniform in this regard, they vary among
themselves. They form depressed, hemispheric or flat, though massive
expansions. The cells vary from .5 mm to 1.5 mm in diameter, and are
prismatic. Long septal spines, reaching nearly to the center of the cor-
allites, are arranged in longitudinal rows. The number of rows of pores
has not been positively determined. The tabulae are thin, flat, horizontal,
closely arranged, from .5 to i mm apart.

This form is well known from the Niagaran and Guelph formations
and has a wide distribution.

Favosites gothlandicus Lamarck

Favosites gothlandica Lamarck, Histoire des Animaux sans Vertfebres.

1816. 11:206
Favosites favosa? Hall, Paleontology of New York. 1852. 2: 126, pi. 34A bis,

fig. 5a-e
Favosites gothlandica Billings, Geology of Canada. 1863. p. 305, fig. 302;

Catalogue of the Silurian Fossils of Anticosti. 1866. p. 32
Favosites gothlandica and favosa Nicholson, Paleontology Prov. of Ontario.

1875. p. 51, 52

Favosites gothlandica Nicholson, Paleontology of Ohio. 1872. 2:224
Favosites favosus Rominger, Fossil Corals. 1876. p. 20, pi. 4, fig. 1-43, pi. 5,

fig. 2
Favosites g o t h 1 a n d i c a Whiteaves (in part), Paleozoic Fossils. 1895. v. 3,

pt 2, p. 50
Favosites gothlandica Lambe, Contrib. Canadian Paleontology. 1899. v. 4,

pt i, p. 3, pi. i, fig. i

With this species has been identified a fragment of a very coarse type
of Favosites from Rochester. The calyxes of this specimen average

GUELPH FAUNA IN THE STATE OF NEW YORK 31

between 2 and 3 mm in width, the tabulae are in the main closely arranged
and the cell walls strong ; the mural pores are provided with a distinct rim,
as observed by others, are much larger than those of specimens referred
to F. n i a g a r e n s i s, are arranged in three rows and set closer together
than in other species. The marginal depressions of the tabulae observed
in F. gothlandicus by Mr Lambe are also easily observable in this
specimen. Septa have not been noticed. The walls of the corallites are
striated concentrically in several places, indicating the growth lines.

To all appearances this is the same form as that described and figured
by Hall asF. favosa? Goldf. from the Niagara limestone at Milwaukee
\pp. «'/.]. F. favosus has been currently considered as a synonym of F.
gothlandicus. Whiteaves, Lambe and Milne-Edwards and Haime do
not recognize that species.

Favosites forbesi Edwards Si Haime

Favosites forbesi Edwards & Haime, Polypiers Fossiles des Terr. Paleoz. 1851.

p. 238
Favosites forbesi Edwards & Haime, British Fossil Corals. 1855. p. 238,

pi. 60, fig. 2a-g

Favosites forbesi Whiteaves, Paleozoic Fossils. 1895. v- 3> P* 2> P- 5°
Favosites basaltica Lambe (in part), Contrib. Canadian Paleontology. 1899.

v. 4, pt i, p. 8

Both at Rochester and at Shelby fragments have been obtained
which differ noticeably from the other specimens in the small size of the
corallites, which average not quite i mm in diameter. Interspersed
between these are less numerous, almost circular, somewhat larger coral-
lites. The walls are rather thin, the tabulae irregularly disposed, the
pores apparently arranged in two rows and the interior of the cells pro-
vided with horizontal scales or squamulae.

It would seem to be a specimen of like character that was identified
by Nicholson1 as coming from Hespeler. In regard to the occurrence of
this species, Dr Whiteaves remarks that it is not included in any of the

"Pal. Ontario. 2d Rep't. p. 56.

32 NEW YORK STATE MUSEUM

lists of fossils from the Guelph formation in the Geology of Canada and
that he has failed to recognize it in any of the later collections received by
the survey.

A comparison of the specimens from New York with the original
description and figures by Edwards and Haime leaves no doubt that, if
their species is valid, these may appropriately be referred to it, for they
show the difference in size of cells and the average cell diameter given by
those authors.

Mr Lambe, however, has lately * expressed the view that the specimens
determined by Nicholson as F. f o r b e s i are identical with F. basalticus
Goldfuss, from which Edwards and Haime had separated it first. These
authors themselves, state that there occur all transitions between the two
sizes of cells, and, as this difference in our specimens is much less marked,
there seems to be good reason for doubting the validity of that species
(F. forbesi). In fact, Mr Lambe describes F. basalticus Goldfuss as
subject to many variations in outward form and in the size and shape of the
corallites. As, however, the dimensions for the corallites are given by him
as varying from 2 mm, or even less, to 4 or 5 mm, while in the Guelph
specimens, as in those described by Edwards and Haime, the diameter of
the two kinds of cells does not quite average i and 2 mm ; and as Mr
Lambe does not cite F. basalticus from the Guelph beds but only from
the Onondaga limestone of Ontario, it seems preferable still to refer these
specimens to F. forbesi E. & H. Both Nicholson \pp. «'/.] and Freeh'
mention as an additional descriptive feature of this species the less sharply
subcylindric form of the cells, a very marked feature of the specimens from
Rochester and Shelby. The difference in the size of the cells is reported
as most marked in young specimens, but becomes obliterated with progress-
ing growth.

'Contrib. Canadian Pal. v. 4, pt i, p. 8.
'Lethaea Palaeozoica, 1:422.

GUELPH FAUNA IN THE STATE OF NEW YORK 33

CtADOPOKA Hall. 1852

Cladopora multipora Hall

Cladopora multipora Hall, Paleontology of New York. 1852. 2:140^1.39,

fig. la-g

Favosites? multipora Nicholson, Paleontology of Ontario. 1875. p. 53
Cladopora multipora Lambe, Contrib. Canadian Paleontology. 1899. v- 4»

pt i, p. 29

This form, with the characters assigned to it by Hall and by Lambe,
is quite common in the upper Shelby layer, occurring in casts in the
compact dolomite which present only the tube fillings, while in the nodules
the cell walls are retained. Hall reports the species from the lower part of
the Lockport limestone at Lockport, and Lambe from the Niagaran of
Lake Temiscamingue, Quebec ; it has not been cited from the Canadian
Guelph. Whitfield lists an undetermined species of Cladopora from the
Guelph of Wisconsin.

The lower Shelby bed frequently contains indistinct masses of a Clado-
pora, which may be also referable to this species.

HALYSITES Fischer. 1813
Halysites catenularius Linne (sp.)

Tubipora catenularia Linne, Systema Naturae, ed. 12. 1767. p. 1270
Catenipora labyrinthica Goldfuss, Petrefacta Germaniae. 1826. 1:75,

pi- 25, fig. 5

Halysites catenularia Edwards & Haime, British Fossil Corals. 1855.

p. 270, pi. 64, fig. la-c
Catenipora e s c h a r o i d e s Hall, Paleontology of New York. 1852. 2:127, pi. 35,

fig. la-i
Halysites c a t e n u 1 a t u s Billings, in Logan's Geology of Canada. 1863. p. 305,

fig- 303
Halysites cat enularia Nicholson, Paleontology Prov. of Ontario. 1875. p. 51,

fig. 24a, b

Halysites catenularia Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 47
Halysites catenularia Lambe, Contrib. Canadian Paleontology. 1899. v. 4,

pt 2, p. 68

** NEW YORK STATE MUSEUM

Specimens of this species occur in the white flint nodules at Rochester,
and also in the dark dolomite, the latter in a condition altogether similar to
that in which they are abundantly found throughout the upper layers of
the Lockport dolomite series. The species is also common at the upper
Guelph horizon near Shelby falls. In the size of the corallites and shape
of the meshes the forms approach that described by Goldfuss as C a t e n i-
pora labyrinthica, but the latter is considered by Whitfield ' as a
variety of Halysites catenulatus, while Whiteaves regards it as
synonymous with the latter, and Lambe asserts that transitions are observ-
able to the forms with large corallites and meshes.

Halysites catenularius, with its varieties has a very wide ver-
tical and horizontal distribution and in Canada occurs both in the Guelph
and Niagara beds.

Halysites agglomeratus Hall (sp.)

Catenipora agglomerata Hall, Geology of New York ; report on fourth dis-
trict. 1843. table 22, fig. 2

Catenipora agglomerata Hall, Paleontology of New York. 1852. 2:129,
pi. 35 bis, fig. 2a-g

Halysites agglomerata Nicholson, Paleontology Prov. of Ontario. 1875.
p. 51, fig. 24C, d and p. 66

Halysites a g g 1 o m e r a t u s Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 48

Numerous fragments consisting of rather long straight chains composed
of nearly round, rather large corallites have been observed at Rochester
and in the upper Shelby dolomite. Hall termed forms with this char-
acter Catenipora agglomerata. Nicholson reports the species
from the Guelph of Ontario ; while Lambe [pp. cit. p. 67, 68] believes that
the corallum of H. catenularius adopted the agglomerata mode of
growth when its lateral expansion was interfered with or restricted, and
asserts that both oval and circular corallites are found in the same corallum.
These fossils are too scantily represented in the Rochester material to per-
mit any conclusion in regard to the relation of the species in question.

'Geol. Wisconsin. 1882. 4:271.

GUELPH FAUNA IN THE STATE OF NEW YORK 35

There have also been observed in this material a few fragments con-
sisting of alternating rows of large corallites with smaller rectangular ones.
This variation has been reproduced by Lambe [pi. 3, fig. 2] and is regarded
by him as belonging to Halysites catenularius, his specimen com-
ing from the Niagaran of Ontario.

BVB1NGOPORA GoldfuSS, 1826

Syringopora infundibulum Whitfield

Plate i, fig. 6-9

Syringopora infundibula Whitfield, Geol. Sur. Wisconsin. Annual Report.

1877. p. 79
Cystostylus infundibulus Whitfield, Geology of Wisconsin. 1882. p. 274,

pi. 14, fig- 7

Cystostylus infundibulus Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i, p. 2
Cystostylus infundibulus Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,

P- 49

Syringopora infundibula Lambe, Contrib. Canadian Paleontology. 1899.
v. 4, pt i, p. 53

A considerable number of nodules of the upper Shelby Guelph are
composed of a Syringopora, identical with the above species originally
described by Whitfield from the Racine limestone at several points in the
vicinity of Wauwatosa and Milwaukee Wis. Whiteaves subsequently
reported the species from the Guelph of Hespeler, Elora and Durham.

The material in hand consists of medium sized, apparently irregular
coralla, aggregations of subparallel, straight or somewhat flexuous corallites,
which have an average diameter of 3 mm and are from 3 to 6 mm apart.
The corallites appear externally as transversely wrinkled, sometimes
abruptly thickened tubes, which multiply by lateral budding and are con-
nected by transverse, hollow connecting processes, three or four of which
are often given off radially in different directions at the same level.

The spiniform septa and funnel-shaped tabulae, characteristic of the
genus, are distinctly shown in natural sections.

The writers share Mr Lambe's doubt whether this species will prove
distinct from the longer established species, S. verticillata Goldfuss,

36 NEW YORK STATE MUSEUM

the more as Rominger, in his very elaborate description of the latter,1
points out that it is very variable in the size of the tubes and their mode of
growth. The dimensions of the two species, as given by these authors, do
not differ materially ; the critical difference therefore rests only in the more
verticillate arrangement of the connecting tubes of the one species, which,
as the Shelby material suggests, may take place at the same level in one
place and at different levels in other portions of the corallum, so that the
latter species may be based on an extreme variation.

Should Syri ngopora infundibulum prove to be a synonym
of S. v e r t i c i 1 1 a t a, the form is not restricted to the Guelph but also
extends down into the Lockport limestone, from which S. verticillata
was described, Goldfuss's types having come from the Niagaran of Drum-
mond island.

The only Syringopora which is described from the Niagaran of New
York is S. multicaulus Hall, which is said to occur in the Lockport
limestone. It appears from the original drawings of that species, that its
corallites are smaller than those of S. infundibulum, and the connect-
ing processes must have been very far apart.

HYDROZOA
STBOMATOPOBA GoldfuSS. 1826

Stromatopora galtensis Dawson (sp.)

Plate i, fig. 13

Coenostroma galtense Dawson, Life's Dawn on the Earth. 1875. p. 160
Coenostroma gait ens e Dawson, Quart. Jour. Geol. Soc. 1879. 35:52
Cf. Strom atopor a const e 1 lata Hall, Paleontology of New York. 1852. 2:324
Stromatopora galtensis Nicholson, Monograph on British Stromatoporidae.

1891. p. 173
Stromatopora galtensis Whiteaves, Paleozoic Fossils. 1895. v-2>Pt3»P-S2

Both at Rochester and in the upper horizon at Shelby occur broad,
flat masses with distinct astrorhizae on the surface but with the interior
mostly dolomitized. These fossils are very similar to Stromatopora

'Geol. Sur. Michigan. 1876. v. 3, pt 2, p. 80.

GUELPH FAUNA IN THE STATE OF NEW YORK 37

constellata Hall of the Coralline (Cobleskill) limestone, but the latter
has the astrorhizae on monticules, a feature not shown in the Rochester
specimens.

Sir William Dawson, in Life's Dawn on the Earth, p. 160, describes
and figures a form from the Guelph which shows such astrorhizae without
monticules, and the same closely laminated interior. Sections obtained
from the Rochester specimens show that the mass is first divided into
"latilaminae," then again in closely arranged laminae, through which pillars
pass continuously. On the basis of these structures the specimen is con-
sidered a true Stromatopora, and as showing no noticeable differences from
Dawson's Coenostroma galtense. The latter was regarded by
Nicholson as probably identical with Str. typica Rosen. This author
also states that Coenostroma constellata (Hall) Spencer1, from
the upper Niagaran of Hamilton Ont, does not appear distinguishable
from C. galtense Daws.

This species forms numerous large concentric masses in the upper
Guelph of Oak Orchard creek. A good specimen exhibiting the astror-
hizae in fine preservation was also obtained from the dark crystalline lime-
stone directly underlying this layer and associated with Enterolasma
c al i c u 1 u s in abundance. In the lower bed occur very frequently cavities
of large size, which are either entirely vacant or filled with a more or less
loose mass of small, white, dolomite crystals. The shape of these cavities
and the occasional retention of one or two concentric layers indicate that
they originated from the dissolution of masses of Stromatopora.

ctATHBODicTYCM Nicholson & Murie. 1878
Clathrodictyum ostiolatum Nicholson

Plate i, fig. 10-12

Stromatopora ostiolata Nicholson, An. and Mag. Nat. Hist. 1873. ser. 4.

12:90, pi. 5, fig. i, a
Stromatopora ostiolata Nicholson, Paleontology Prov. of Ontario. 1874.

pi. i, fig. i, la ; 1875, p. 63

'Univ. State of Missouri. Bui. i. 1884. p. 48.

38 NEW YORK STATE MUSEUM

Clathrodictyon (Stromatopora) ostiolatum Nicholson, Monogr. British

Stromatoporidae. 1886. pt i, p. 14
Clathrodictyon ostiolatum Nicholson, An. and Mag. Nat. Hist. 1887.

ser. 5. 19:11, pi. 3, fig. 1-3
Clathrodictyon ost i olat u m Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,

P- 52

The great majority of the stromatoporoid bodies found in the dolo-
mite of Rochester and in the upper Shelby horizon are small, often incrust-
ing nodular masses with very fine and close lamination, a smooth or finely
granulate surface and conic oscula, the latter a characteristic feature of
Clathrodictyum ostiolatum. In the specimens under observation
they are however not arranged distinctly, as described by Nicholson.
Where the specimens are weathered, they display the characteristic nipple-
shaped prominences of botryoidal appearance. Thin sections show that
the specimens belong to the genus Clathrodictyum as denned by Nicholson
and Murie, specially clear being the succession of calcareous laminae with
intermediate vertical props or dissepiments, which do not penetrate the
laminae, and the " marked off cellular compartments."

This species has hitherto been recognized only in the Guelph of Ontario.

A section presenting the same structure was observed among the
museum collection of slides from a specimen ticketed as coming from the
Coralline limestone at Schoharie. This section also displays distinctly
" the internal cylindrical masses, each composed of laminae concentric with
a long axis," observed by Nicholson in C. ostiolatum, as the internal
continuation of the conic oscula. It seems, therefore, that this species is
common to both the Guelph and the Coralline (Cobleskill) limestone.

BB.ACHIOPODA

CBANIA Retz. 1781
Crania (sp.)

Plate 4, fig. 6

An imperfect upper valve with subcentral beak and squamose con-
centric striae has been obtained in the white chert at Rochester but is not
specifically identifiable.

GUELPH FAUNA IN THE STATE OF NEW YORK 39

MONOMKRELLA BillingS. 1 8/1

Monomerella noveboracum sp. nov.

Plate 2, fig. 1-6 ; plate 3, fig. 1-7 ; plate 4, fig. 38

Shell large, thick ; brachial valve subovate ; pedicle valve elongate,
subovate in marginal outline, the greatest width at midlength or sometimes
a little in front of it, thence tapering with convex sides to a bluntly triangu-
lar erect umbo ; the brachial valve broader, lilunter and more curved than
the pedicle valve. Pedicle valve gently convex, almost straight in profile ;
brachial valve strongly convex, with the greatest prominence posterior to
the middle. The surface ornamentation consists of conspicuous growth
lines.

Pedicle valve. Cardinal area large, broad, flat, elongate triangular,
slanting obliquely inward and divergent from that of the brachial valve ;
subdivided longitudinally into a broad, flat, depressed median area (pedicle
groove) bounded by lateral ridges and broad, smooth areal borders. Median
area higher than broad, crossed by coarse, lamellose growth lines. Supra-
cardinal slope narrow, very oblique and incurved ; cardinal faces narrowly
triangular, curving outward, merging into a prominent and very broad car-
dinal buttress, which extends nearly the entire length of the platform.
Hinge transverse, much depressed. Platform well developed, extending
about half the length of the valve, linguate, widening slightly anteriorly ;
front obliquely and obtusely angular. Umbonal chambers in most speci-
mens very deep, wide mouthed and broad. Platform vaults not developed.
Crescent distinct below the hinge line ; lateral and terminal parts readily
distinguishable, the latter more impressed. Transverse scars forming an
oval impression between terminal crescents and platform. Platform scars
finely and obliquely striated ; extending apparently the full length of the
umbonal chamber. Umbo-lateral scars not distinguished. A broad, low
ridge extends from the anterior edge of the platform to the front margin of
the valve.

Brachial valve. Shorter by nearly one third than the pedicle valve,
broadly ovate, with a low, rotund beak, and transverse hinge which is

40 NEW YORK STATE MUSEUM

strongly raised in the middle. Umbonal cavity simple, deep and broad.
Platform very large, moderately elevated, extending three quarters the
length of the valve, with V-shaped anterior margin, and rounded, projecting
antemedian point ; slightly excavate on its anterior walls, often to the
extent of forming shallow platform vaults. Anterior septum a low, broad
ridge, more prominent than in the pedicle valve. Crescent appearing as a
well defined impression on the cardinal slope, its sides and ends curving for-
ward and being broader and less distinct. Transverse scars distinct, sub-
circular depressions. Umbo-lateral scars rather faint and small, lying at the
sides of the umbonal cavities. Both median and anterior scars of the plat-
form sharply defined, depressed below the lateral scars, which are obliquely
striate.

Horizon. Lower Shelby dolomite, Oak Orchard creek.

This large and ponderous shell has been found only at the locality
cited, but is there in very great abundance ; it is surpassed in number of
individuals only byTrematonotus alpheus and Poterioceras
sauridens. Some of the specimens are impressions of the exterior of
the shell.

This species is in many respects closely related to M. prise a Billings,
whose characters have been described by several authors,1 though nothing
is yet known of its exterior. So obvious is this relationship that M. n o v e -
boracum is evidently a local, more prosperous development of that
widespread Guelph species. It is, however, sufficiently different to neces-
sitate distinction. It is larger, the specimens attaining a length of 80 mm
and a width of 65 mm ; the umbonal cavities are, in most specimens,
absolutely and relatively much longer, some attaining a length of 35 mm ;
the umbo of the pedicle valve however is less acutely, but more broadly
tapering ; the cardinal area, pedicle surface and areal borders are therefore
relatively broader. The platform of the brachial valve extends farther
anteriorly, and the anterior septa of both valves extend as broad distinct

1 See Billings, Paleozoic Fossils. Nicholson, Pal. Ontario. Whiteaves. Davidson.
Hall & Clarke. Pal. N. Y. v. 8, pt i.

GUELPH FAUNA IN THE STATE OF NEW YORK 41

ridges to the anterior margin. In size this form rivals M. durhamensis
Whiteaves, which however is readily distinguished by its extremely large
and prominent beaks in both valves. In some features the species is still
more closely related to M. walmstedti Dav. & King than to M. prisca.
Monomerella walmstedti is a species from the corresponding beds
of Gothland, which has a similar development of the umbo and cardinal
region, but possesses a more convex umbo m the pedicle valve. Davidson
points out the close relationship of that species with M. prisca. Mono-
merella noveboracum shows relationship also, in the character
of its brachial valve, with M. kingi Hall & Clarke, from the Niagaran
dolomites of Hawthorne 111.' This Shelby species is the only representa-
tive of the family Trimerellidae yet found in the State of New York.

DALMANXXLA Hall & Clarke. 1892
Dalmanella cf. elegantula Dalman (sp.)

Plate 4, fig. 9

For synonomy of Orthis elegantula see Hall & Clarke, Paleontology of New
York. 1892. v. 8, pt i, p. 207, and Davidson, Monogr. British Silurian
Brachiopoda.

Some small and incomplete specimens of immature individuals found
at Rochester and in the upper Guelph at Shelby suggest affinity with the
specific type of Dalmanella elegantula in the relative convexity
of the two valves and the character of the surface sculpture so far as
retained.

The presence of casts of the interior of two species of Orthis in the
Guelph of Ontario is mentioned by Whiteaves ; and it is also cited from
the Guelph beds at Cedarburg Wis.a

1 See Pal. N. Y. v. 8, pt i, pi. 40, fig. 2.
"Geol. Wisconsin, 2:379.

42 NEW YORK STATE MUSEUM

Dalmanella cf. hybrida Sowerby (sp.)

Platt 4, fig. 7, 8

Orthis hybrida Sowerby, in Murchison's Silurian System. 1839. p. 630, pi. 13,

fig. ii
Orthis hybrida Hall, Paleontology of New York. 1852. 2: 253, pi. 52, fig. 4a-c ;

and authors generally

A single depauperated ventral valve with the characters of this species
has been observed in the chert nodules at Rochester. Orthis hybrida
is found at various outcrops of the Racine beds of Wisconsin, but has not
been elsewhere identified in typical Guelph rocks.

Dalman. 1828
Leptaena rhomboidalis Wilckens

For synonymy see Schuchert, United States Geol. Sur. Bui. 87, p. 240
Under the name L. depress a, Hall r reports this species as com-
mon in the Rochester shale and rare in the Lockport limestone. A single
small specimen has been obtained from the lower Shelby dolomite. As this
cosmopolitan shell is not mentioned from the Guelph of Canada or Ohio, in
Wisconsin has been reported only from one locality of that formation, and
is entirely absent from the upper horizon at Shelby and Rochester, it evi-
dently found very uncongenial conditions in the Guelph basin.

SPIRIFKK Sowerby. 1815
Spirifer crispus (Hisinger) Hall

Plate 4, fig. 10-20

Spirifer crispus Hall, Paleontology of New York. 1852. 2 : 328, pi. 74, fig. ga-h
The Spirifers occurring in the upper Shelby horizon both at Rochester
and Oak Orchard creek present features of considerable interest and signifi-
cance. They naturally fall into two groups, one of small and broad forms,
of which numerous specimens have been observed, the other of larger and
relatively longer form, occurring in but restricted number.

The smaller of these is identical in expression with the S p. cris-
pus described by Hall from the Coralline (Cobleskill) limestone. All the

'Pal. N. Y. 2:258.

GUELPH FAUNA IN THE STATE OF NEW YORK

43

specimens before us from Rochester and Shelby, as well as those described
from the Coralline limestone of eastern New York, agree in having the pli-
cations obsolete, while they distinctly show the fine concentric striae with
minutely setose edges, characteristic of that species. Hall expressly states
that these Coralline forms possess no distinctive features from the Niagaran
specimens of this very variable species, and he therefore had " no hesitation
in referring the specimens from the Niagara and the Coralline limestone to
the same species." At the same time it seems that there is, in the progress
of this species, a decided tendency toward the development of smooth forms,
as is evinced by the replacing of the strongly plicated shells of the Roch-
ester shales by the smooth forms in the Coralline and the Guelph dolomites.

In the upper horizon on Oak Orchard creek a few faintly ribbed speci-
mens indicate the derivation of the smooth mutation from the typically
costate form. But they also contrast strongly with the highly plicate forms
found abundantly in a fossiliferous limestone layer in the Lockport lime-
stone above the lower Shelby bed and among which there are found no
smooth specimens. In the lower fauna Spirifer is entirely absent.

A similar smooth expression of S p i r i f e r crisp us in the dolomites
of the Manlius horizon has been recently observed by A. W. Grabau in
western New York and described as Spirifer eriensis.1 Dr Grabau
emphasizes the very close relation of his form with the Coralline (Coble-
skill) limestone variety of Spirifer crispus for which he has proposed
the varietal term corallinensis. These smooth varieties of the species
thus extend to the top of the Siluric.

The larger form is too robust to be considered a variety of S p. cris-
pus. It is also distinguished by the subtriangular outline, and the long
extended beak of the pedicle valve. The sinus is extremely shallow and
can hardly be characterized as flanked by folds. Parts of the shell adhering
to the cast exhibit concentric imbricating lines. A comparison with S p.
bicostatus at once suggests itself, but the form from the Guelph dolo-
mite is still larger than the typical forms of that species, has the extremities

'Geol. Soc. Am. Bui. n. 1900. p. 366. pi. 21, fig. 23, b.

44 NEW YORK STATE MUSEUM

more angular and lacks the distinct folds on either side of the sinus. In
these features, differential from Sp. bicostatus, it agrees with a large
form which is described and figured by Hall from the Coralline limestone
as " S p i r i f e r s p." ' and is stated to be closely allied to Sp. crispus but
differing in size. This agreement extends even to four of the five very low
costae observed on the casts from the Coralline limestone of Schoharie.
The form from the Guelph dolomite [see plate 4, fig. 21, 22] unites the
characters of Sp. bicostatus with this unnamed Spirifer. Sp. bico-
status in New York is only known from its original locality, Vernon
Center in Oneida county, in the eastern extension of the Lockport lime-
stone. It seems, therefore, probable that this group of forms is restricted
to the Guelph dolomite, the eastern extension of the Lockport limestone
in the center of the State, where the stratigraphic relations are not fully
known, and to the Coralline limestone.

Whiteaves2 states that the characters of two ventral valves from
the Guelph at Durham Ont. are so similar to those of Sp. bicostatus,
as described and figured by Hall, that it is possible these should be referred
to that species rather than to S p. p 1 i c a t e 1 1 u s. This species and its
variety, r a d i a t u s, replace Spirifer crispus in the western Racine
and Guelph beds, from which the latter has not been reported.

WHITFIKLBELLA Hall & Clarke. 1892
Whitfieldella nitida Hall

Plate 4, fig. 31-37

Atrypa nitida Hall, Geology of New York; rep't on fourth dist. 1843. table
of organic remains 13, fig. 5

This is the most common brachiopod in the higher horizon of the
Guelph dolomite at Shelby and at Rochester. Most of the examples are
relatively small, in this feature approaching more nearly the New York
Niagaran than the Waldron, Indiana, specimens. One exhibits lateral
folds, an occurrence at times observable in the Waldron shell.

'Pal. N. Y. 2: 327, pi. 74, fig. 7, 8a-d.
"Paleozoic Fossils, v. 3, pt 2, p. 62.

GUELPH FAUNA IN THE STATE OF NEW YORK 45

Whitfieldella nitida Hall is not reported from the Guelph
limestone of Canada. It is there replaced by W. hyale Billings (sp.)
which is said to be abundant at all localities. The Rochester specimens
are distinctively different from the latter, which is broader shouldered, has
its greatest width more posteriorly and is less convex. The majority of
them however have a broader outline than the typical Lockport specimens,
a feature in which they approach W. nu-cLeolata Hall, the Coralline
limestone representative of the genus, but they still differ from the latter in
not having a distinct sinus and indentation of the anterior margin. Hall1
makes the interesting statement that these broader forms occur in the
Lockport limestone of eastern Wayne county and in Cayuga county, that
they have not the full development which the same species has in the shale
at Rochester, and that they are not easily distinguished from the less
characteristic specimens of W. nucleolata. The forms from the Guelph
dolomite here considered seem to agree most closely with these eastern
shells from the Coralline limestone.

Whitfieldella hyale is reported by Whitfield from the Wis-
consin Racine and Guelph beds, while W. nitida is mentioned only from
the Racine beds. As the latter species has not been cited from the
Guelph of Ohio it appears to be present in that formation only in New
York. It is entirely absent from the lower horizon at Shelby.

CAMAKOTOKCHIA Hall & Clarke. 1892
Camarotoechia (?) neglecta Hall (sp.)

Plate 4, fig. 18-31

Atrypa neglecta Hall, Paleontology of New York. 1852. 2: 274, pi. 57, fig. la-p
Rhynchonella n e glee t a Hall, N. Y. State Mus. 28th An. Rep't. 1879. P- 162,

pi. 26, fig. 1-6
Rhynchonella neglecta Beecher & Clarke, N. Y. State Mus. Mem. i. 1889.

p. 37, pi. 4, fig. 3, 6-8

Characteristic specimens of this species are quite common in the white
chert of the Rochester and the upper Shelby dolomite. They seem to

'Pal. N. Y. 2:329.

46 NEW YORK STATE MUSEUM

agree more closely with the shell as it occurs in the Rochester shales of
New York than with the representatives of the species at Waldron Ind., the
latter having the plications less blunt and the sinus more pronounced.

The species has a wide distribution in the Niagaran beds, and is listed
from some of the Guelph localities in Wisconsin. It has not been found in
the Canadian Guelph. These specimens do not approach Rhynchon-
ella pisa Hall & Whitfield, the only species of the genus recognized by
Whiteaves in the Guelph fauna of Ontario \pp. cit. 1895. p. 63].

Camarotoechia (?) indianensis Hall

Plate 4, fig. 26, 27

Rhynchonella indianensis Hall, Albany Institute. Trans. 1863. 4:215
Rhynchonella indianensis Hall, N. Y. State Mus. z8th An. Rep't. 1879.

p. 163, pi. 26, fig. 12-22
Rhynchonella indianensis Beecher & Clarke, N. Y. State Mus. Mem.

i. 1889. p. 42, pi. 3, fig. 17-28

This species is represented by a few specimens from the Rochester
and Shelby horizons.

It, as well as C. (?) n e g 1 e c t a, is decidedly more common in the chert
nodules of the upper Shelby dolomite than at Rochester. In the lower
Shelby bed it is still less frequently observed.

Camarotoechia (?) indianensis occurs freely in the Niagaran
at Waldron Ind., and at Louisville Ky., but has not been recorded in the
Niagaran beds of New York.

BHYNCHOTBETA Hall. I §79

Rhynchotreta cuneata americana Hall

Plate 4, fig. 23-25

Atrypa cuneata Hall (non Dalman), Geology of New York; rep't on fourth dist.
1843. table of organic remains 13, fig. 3, 4
For synonomy see Hall & Clarke, Pal. N. Y. v. 8, pt 2, p. 185

In the upper Guelph of the Oak Orchard creek section a single normal
specimen of this shell was obtained, exhibiting the cuneiform outline, con-
cave cardinal slopes and angular plications curving outward toward the

GUELPH FAUNA IN THE STATE OF NEW YORK 47

lateral margins. The plications are not quite as prominent as in the typical
Rochester shale specimens.

This shell is widely distributed in the Niagaran of North America,
where it occurs in the Rochester shale, Waldron and Osgood beds ; but it
seems to be absent from the higher beds of the Niagaran, and has not been
observed before in the Guelph. Its appearance, though extremely rare, in
the Guelph of Oak Orchard creek, is hence worthy of notice.

LAMELLIBBANCHIATA
MYTItARCA Hall. 1870

Mytilarca eduliformis sp. nov.

Plate 5, fig. 8-10

Shells rather small, valves ovate acuminate, very narrow at the beaks,
with slightly concave anterior margins, broadly rounded at the base and at
the postlateral extremity, the posterior cardinal margin being straight.
Beaks narrow, subacute and directed forward. Surface elevated along the
umbonal ridge which runs from the beaks to the antelateral curve. From
this ridge the surface is abruptly incurved and almost vertical. Posteriorly
the slope is very much more gradual, and the ridge loses its prominence
over the basal region. The ornament is not well preserved, but patches of
the shell show fine concentric lines without other modification.

Dimensions. This description is based on two specimens, one of which
retains the valves in normal juxtaposition. The valves have a length of
20 mm and a width at three fourths their length of 1 5 mm.

Observations. This shell has a noteworthy resemblance in form and
contour to a small example of the living Mytilus edulis. It is pro-
visionally referred to the genus Mytilarca, though some generic distinction
may eventually be found between this and the typical upper Devonic repre-
sentative of the genus. The only American Upper Siluric species which
has heretofore been referred to Mytilarca is the M. sig ilium Hall from
the Niagaran at Waldron Ind.

Mytilarca eduliformis is from the white chert at Rochester.

48

NEW YORK STATE MUSEUM

Mytilarca acutirostrum Hall

Plate 5, fig. ii, 12

Ambonychia acutirostra Hall. N. Y. State Cab. Nat. Hist, noth An. Rep't.

1867. p. 336, pi. 14, fig. 2
Ambonychia acutirostra Hall. N. Y. State Mus. 28th An. Rep't. 1879.

p. 171, pi. 7, fig. 12

Several internal casts of this shell, rather below medium size, were
obtained from the lower bed at Shelby. They are characterized by their
full, relatively long valves with produced, acute beaks, straight, short car-
dinal line, straight and slightly convex anterior margin which extends
almost the whole length of the valve, very convex basal and less rounded,
almost straight and oblique posterior margin, which forms an obtuse angle
with the short wing of the posterior cardinal region. The umbo is very
prominent and convex ; from it a slightly elevated and distinct umbonal
ridge extends to the anterobasal angle. Thence the valve slopes evenly
toward the posterior margin, and more abruptly toward the anterior margin.
No muscular impression has been observed on the somewhat incrusted casts.
The impression of a distinct, narrow ligamental area, extending the full
length of the cardinal line, and of two oblique lateral teeth at the extreme
posterior end of the cardinal line are noticeable.

Observations. This form differs from the foregoing both in size, and
in its slightly convex anterior margin. We have identified these shells
with Ambonychia acutirostrum, a species which was described by
Hall from the limestone of the age of the Niagaran group, near Mil-
waukee. In the 28th report of the New York State Museum it is said to
be associated, in Wisconsin and Illinois, with Ambonychia aphaea,
described from Wauwatosa Wis. and Bridgeport 111. Professor Whitfield1
cites the species from the Racine beds of Racine, Greenfield, Waukesha
and Wauwatosa, and from the Guelph beds of Cedarburg, it being the only
Guelph lamellibranch mentioned besides Megalomus canadensis.
It has not been reported from the Canadian Guelph.

'Geol. Wisconsin, 2:372-79.

GUELPH FAUNA IN THE STATE OF NEW YORK 49

Hall referred his species with doubt to Ambonychia. Ulrich' refers
the form to Mytilarca, a view which is verified by the evidence of lateral
teeth.

Mytilarca acu t irost ru m is, as indicated by Hall, very similar
to Myalina mytiliformis Hall from the gray Clinton limestone of
New York. From the latter species M. acutirostrum was said to differ
in its more acute beak and relatively greater width. In regard to width
our specimens are intermediate between the two species, but in the charac-
ter of its beak it is more like the western Guelph form. Foerste2 has
described still another Clinton form as Mytilarca mytiliformis,
but as Hall's Ambonychia mytiliformis is a Mytilarca [p. 560 of
same paper] the species should be renamed (M yt. foerstei nom.
propos.},

PTEBINEA GoldfuSS. l826

Pterinea subplana Hall (sp.)

Plate 5, fig. 4

Avicula subplana Hall, Paleontology of New York. 1852. 2:283, pi- S9» ^g-
3*, 3b, 3c

Internal casts from the Rochester chert and the upper horizon at
Shelby indicate a depressed right valve with long straight hinge line, beak
subanterior and not prominent, slightly projecting above the hinge line.
The ear is short and apparently rounded, the posterior wing is much
extended, obliquely truncated and set off from the body of the valve by a
low and broad depression. A long narrow cartilage pit extends from the
beak three fourths the length of the posterior cardinal line and parallel to
it. SuVface with concentric lines.

The left valve shows a greater convexity and similar outline.

Avicula subplana is a Rochester shale species which has not been
reported from the Guelph of Canada or the Interior.

1 Geol. Sur. Minnesota, v. 3, pt 2, p. 494.
2Geol. Ohio, 7:5^9.

(JO NEW YORK STATE MUSEUM

Pterinea undata Hall (sp.)

Plate 5, fig. 6

Avicula undata Hall, Paleontology of New York. 1852. 2: 283, pi. 59, fig. 2
A single cast of the left valve. This, in its oblique form, short hinge

line, prominent umbo, and much elevated, rounded umbonal ridge, agrees

closely with this shell as described by Hall from the Rochester shale. The

concentric undulations are also indicated on the cast.

We are not aware that this species has been obtained in either the

Canadian or western Guelph. The specimen described is from the upper

Shelby dolomite.

CONOCARDIUM Bronn. 183^

\j *j

Conocardium sp.

Plate 5, fig. 7

Several small Conocardia, poorly preserved, have been noted in the
Guelph at Rochester. These indicate a shell somewhat similar to the little
known C. ornatum Winchell & Marcy1 from the Niagaran dolomites of
Illinois, but seem to lack the sharp ornamentation of the umbonal ridge.
This ridge is greatly elevated, and the body of the shell is short, so that
both anterior and posterior slopes are steep, but the former is much the
more abrupt and is concave. The surface of the posterior slope bears nine
to 10 ribs with five to six on the anterior.

Whiteaves mentions the frequent occurrence of a small Conocardium
in the Guelph at Durham and thinks it probably an undetermined species,
but gives no clue to its characters.

MO mo tor sis Hall. 1847 0

Cf. Modiolopsis subalata? Hall

Modiolopsis subalatus? Hall, Paleontology of New York. 1852. 2: 285, pi. 59,

fig- 7

A somewhat incomplete cast of both valves, from the upper Guelph at
Oak Orchard creek, exhibits the characteristics of the Rochester shale

'Boston Soc. Nat. Hist. Mem. i. 1866. p. in, pi. 2, fig. 15.

GUELPH FAUNA IN THE STATE OF NEW YORK 5!

specimens, which were identified with qualification by Hall with the Clinton
form of his species. It differs to some extent in possessing a slight depres-
sion extending forward from the umbo, which is not mentioned in the
description of M. s u b a 1 a t a .

GASTROPODA

Montfort. 1808

Bellerophon shelbiensis sp. nov.

Plate 5, fig. 13-19

Bucania stigmosa? (Hall) Whiteaves, Paleozoic Fossils. 1884. v. 3, pt I,

p. 34, pi. 5, fig. 3, 3a; pi. 8, fig. 4
Not Bucania stigmosa Hall, Paleontology of New York. 1852. 2:92, pi. 28,

fig. 8, 8a-e

Dr Whiteaves has figured from the Guelph of Gait internal casts of a
symmetric shell which he refers to as Bucania stigmosa? Hall. With
regard to these he says :

These agree perfectly with similar but better preserved casts from the
Niagara formation at Grimsby Ont, in the museum of the survey, which
have been identified with B. stigmosa by E. Billings, but in the absence
of any knowledge of the shell of the Gait specimens their determination
must be regarded as doubtful.

A considerable number of similar casts from Shelby leaves no doubt
that this form is well distinguished from Hall's Clinton species, Bucania
stigmosa, for, besides attaining a size thrice as large, it distinctly differs
in the cross section of its whorls, which are more convex on the dorsal and
more deeply concave on the ventral side, the whorls embracing somewhat
more than in the Clinton species.

Diagnosis. Shell somewhat below medium size, having an average
diameter of 15 mm and rarely attaining more than 25 mm; consisting of
about three volutions which increase but slowly in size ; whorls embracing
about one third of the hight, lowly subtriangular in cross section, with a
dorsal carina which, bearing the slit-band, becomes more prominent as
growth advances. The sides are convex, full or evenly rounded in young
stages, becoming more gently convex in later growth, abruptly sloping to

C2 NEW YORK STATE MUSEUM

the umbilicus, which appears relatively large on internal casts but as indi-
cated by casts of the exterior was actually very small, the shell being con-
siderably thickened along the umbilical edge. Aperture but little expanded
laterally, broadly triangular reniform, outer lip with a shallow sinus, inner
lip not observed. Surface ornamentation not sufficiently known, apparently
consisting only of growth lines.

Horizon. Lower Shelby dolomite.

As Whiteaves reports this species from the Guelph at Gait and from the
Niagaran formation at Grimsby Ont, it suggests itself that also in Canada
this form may appear in an early manifestation of the Guelph fauna, as
in New York. From B. tuber Hall, the only other species of Bellerophon
described from the Niagaran, B. shelbiensis differs in the laterally more
expanded aperture and the deeper sinus of the outer lip. We have no
record of the occurrence of other species of true Bellerophon in the Ameri-
can Niagaran; and, in view of the large representation of the genus in the
Lower Siluric and Devonic, it is evident that the facies in which this genus
flourished in Niagaran time has not yet been brought to notice.

Though this shell was identified by Billings and Whiteaves with a
species of Bucania, we feel justified in referring the form to Bellerophon.
In the differentiation of Bellerophon and Bucania, the character of the sur-
face sculpture is considered by various writers (de Koninck, Waagen,
Koken) of critical importance ; and this feature is not clearly exhibited in
the Shelby material, but the character of the umbilicus, and of the section of
the whorls is distinctly bellerophontid. The umbilicus has been described
above ; and the section is not flat on the dorsum and angulated at the edge,
as in the generic type of Bucania, but rounded and embracing with the edges.
All through the literature of paleozoic gastropods the distinction of Hall's
genus Bucania from Bellerophon has been involved in much uncertainty
and doubt. Professor Hall did not originally define the genus sufficiently
to avoid misconception. It seems evident that, as suggested by Koken and
Ulrich, Hall used B. expansa as type of his genus, but, as he described
B. sulcatina as the first species of the genus, this had to be taken as

GUELPH FAUNA IN THE STATE OF NEW YORK 53

typical, and B. expansa has been construed as a species of Roemer's later
genus, Salpingostoma. De Koninck and Waagen, in the endeavor to define
the genus more clearly, based it on the presence of revolving lines. Koken,
who intimates that Hall when defining the genus evidently had before him
species of the subsequently established genera, Salpingostoma and Trema-
tonotus, bases the genus onB. sulcatina and defines it by its flat dor-
sum, wide umbilicus, slightly expanded peristome and coarse, wrinkled
revolving lines, crossed and interrupted by transverse lamellae. He also
includes in this genus the Devonic and Carbonic species bearing these char-
acters, and is followed in this view by Clarke, who has described a Devonic
Bucania.1 Hall, on the other hand, states2 that there are no Bucanias younger
than the B. profunda (which is a Trematonotus) of the Helderbergian,
so that there obviously exists a considerable difference between Hall's and
Koken's conceptions of Bucania. Lindstrom, in his work on the Silurian
Gastropoda of Gothland, does not recognize the genus at all, but unites it
with Bellerophon, on the ground that it has the wide aperture in com-
mon with most of the Bellerophons, and that the wide umbilicus and the
spiral striae are not of enough importance to be of value as generic distinc-
tions. The claim of Fischer3 and Lindstrom, that Hall ultimately aban-
doned the generic term Bucania and reunited the form with Bellerophon,
seems to be based on a misconception, as Hall, in Paleontology of New
York, v. 5, states only that the B. devonica is probably not Bucania,
and that this genus does not enter the Devonic.

In contrast with Lindstrom's extreme conservatism, Ulrich places Belle-
rophon and Bucania in different families, the Bellerophontidae and
Bucaniidae. He recalls Koken's observation as to the differences in the
aperture and surface sculpture between the " Sulcatina typus " and the
Devonic and Carbonic species, and holds the opinion that Bucania, in its
restricted sense, is " strictly a Silurian genus and possibly not even repre-

1 Paleozoic Faunas of Para.

2 Pal. N. Y. v. 5, pt 2.

3 Manuel de Conchyliologie, p. 854.

54 NEW YORK STATE MUSEUM

sented in the upper Silurian." The spirally ribbed later species are united
by this author under a new generic term, Bucanopsis. As these forms do
not differ from Bellerophon in other features than the cancelation of the
surface, the genus is placed among the Bellerophontidae. To Bucanopsis
are referred the well known Hamilton species Bell. 1 e d a and B. 1 y r a.
If our Guelph species should prove to be ornamented with spiral lines, it
would also be referable to Bucanopsis.

TREMATONOTCS Hall. 1 868 (emend.)
Trematonotus alpheus Hall

Plate 5, fig. 20-23 ; plate 6, fig. 1-9

Tremanotus alpheus Hall, separately printed in advance for N. Y. State Cab.

Nat. Hist. iSth An. Rep't. 1865. p. 43
Tremanotus a 1 p h e u s Hall, N. Y. State Cab. Nat. Hist, 2oth An. Rep't. 1867.

P- 347, Pi- IS, "§• 23, 24
Tremanotis alphe us McChesney, Chicago Acad. Sciences. Trans. 1859. v. r,

pi. 8, fig. 4a, b
Bellerophon (Bucania) p erf o rat u s Winchell & Marcy, Boston Soc. Nat.

Hist. Mem. 1866. v. i, no. i, p. 108
Tremanotus alpheus Whitfield, Geol. Sur. Ohio. v. 2, Paleontology, p. 145,

pi. 8, fig. i

Tremanotus angustatus Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 70
Not Bucania chicagoensis McChesney, Description of New Species of Fos-
sil from Paleozoic Rocks of Western States (advance extr. Chicago Acad. Sci.

Trans, v. i). 1859. p. 69, pi. 8, fig. sa, b (plate published at a later date)
Probably Bucania angustata Hall, Paleontology of New York. 1852. 2:349,

pi. 84, fig. ?a-d

Of this remarkable type of symmetric gastropod structure, three speci-
mens have been observed in the material from the Guelph horizon at Roch-
ester, one from Newman's quarry, one among the fossils from the same
horizon (upper Shelby) at Oak Orchard creek and not less than 100 internal
and external molds in the collection from the lower Shelby bed. Two of
the Rochester specimens are in a fair state of preservation, and most of the
lower Shelby examples are excellently preserved, much better than are the
originals of the species, as they retain the surface markings and the aper-

GUELPH FAUNA IN THE STATE OF NEW YORK 55

tural expansion in neanic, ephebic and gerontic conditions. They permit,
therefore, the addition of some important facts to the description of that
species.

Description. Shell subdiscoid, involute ; whorls three to four ; in
section subcircular to roundly elliptic, with inner groove, the outer whorl
being impressed on the inner. The aperture has a flaring lip, which is
turned outward by rather abrupt curvature till it stands at right angles to
the axis of the body whorl and is then reflected. This lip attains, in one
specimen, in its longer axis, a length of 65 mm, and in its minor one a
length of 50 mm. The inner lip was folded back over the last whorl to
such an extent that it covered about one third of it.

Most transverse sections of the shell show symmetric enrolment of the
whorls, but a few, undisturbed in their growth, evince indications of asym-
metry in early growth. This condition, however, has not been demonstrated
a normal feature.

The degree of involution seems to have been subject to some variation,
as there is some difference in the specimens in the width of the umbilicus
at full growth. In the great majority, however, the volutions embrace suf-
ficiently to make the umbilicus relatively small. The whorls are abruptly
convex around the umbilicus.

The surface ornamentation consists of about 20 coarse flat topped
revolving ridges, on each side from keel to umbilicus ; these are separated
by equally wide furrows with generally a smaller rib between them. The
ribs have a somewhat irregular undulating course, periodically swelling and
contracting, giving the surface a peculiarly irregular appearance. These
irregularities are caused by intersection with incised concentric lines,
beyond which the revolving ribs appear out of position. The ribs are also
intersected by broad, transverse folds, which curve obliquely backward
across the whorls. These are most distinct near the umbilicus and become
faint near the dorsal keel. On the outside of the peristome the ribs
become quite abruptly coarser ; and in gerontic specimens they change, on
the outer lip, into broader, less keeled ribs, and the smaller intercalated

56 NEW YORK STATE MUSEUM

ribs disappear entirely, so that in such individuals the peristome bears a
very distinct ornamentation. Casts of the interior surface of the shell
demonstrate that the latter was almost entirely smooth, and bore no other
traces of the highly sculptured surface ornament than occasional very faint,
low, revolving undulations or obscure indications of the transverse ribs.

The transverse folds by which the surface sculpture is crossed, are
apparently the results of the repeated production and absorption of the
expanded mouth. The development of the latter at more or less frequent
intervals is a noteworthy difference from the earlier Siluric forms referred
by Ulrich to the genus Salpingostoma F. Roemer,1 the fundamental distinc-
tion, however, being in the character of the perforations on the slit-band,
which in Trematonotus are elliptic, with everted margins, while in Salpin-
gostoma the perforation is a single long and continuous but inclosed slit.

In T. alpheus the perforations are located on an elevated, narrow,
dorsal keel, which does not extend on the peristome, but is there followed
by a depression extending to the margin of the outer lip. To the keel cor-
responded a deep groove on the inside of the shell. The groove and per-
forations disappear where the inner lip of the peristome reclines on the
penultimate volution, and closes the perforations. The number of perfora-
tions left open varies from six to nine.

Dimensions. A large specimen with gerontic characters measures from
the outer edge of the aperture to the dorsal side of the early part of the
ultimate volution, 75 mm. The major diameter of the aperture was about

57 mm and the vertical diameter of the shell 51 mm.

Observations. The genus Tremanotus (recte Trematonotus Fischer)
was erected by Hall as above cited for this species, the original specimens
being from the Chicago limestone. Professor Hall had earlier described
from the Guelph formation at Gait Bucania angustata,2 a species

•The type of this genus, S. macrostoma, is a middle Devonic shell. It is yet to
be demonstrated that the Trenton shells which have been referred to it are congeneric
with this species.

* Pal. N. Y. 1852. 2:349, pi. 84, fig. 6a, b.

GUELPH FAUNA IN THE STATE OF NEW YORK 57

based on internal casts in a rather inferior state of preservation. Dr
Whiteaves holds this fossil to be identical with T. alpheus, and while
this is probably true, conclusive evidence of the exterior and apertural
characters of the Canadian Guelph specimens still fails us, and we have no
recourse except to continue the recognition of the term here adopted. It
has been contended that McChesney's name, Bucania chicagoensis,
has priority over T. alpheus, the description having been published in
advance of that of the latter, but it was unaccompanied by illustration at
its first description, and the original figure shows it to be a much larger
and more widely umbilicated shell. On the same plate with this figure are
others referred by McChesney to T. alpheus.

Whiteaves was inclined to believe that all three may be found identi-
cal with T. dilatatus Sowerby, because Billings had identified a speci-
men from the Niagaran of L'Anse a la Vieille on the Bay of Chaleurs,
and another from " Division 2 " of the Anticosti group, with that species.
A comparison of our material with Sowerby's excellent figures and McCoy's
more complete description convinces us that the form in hand is distinct
from the Ludlow and Wenlock species, for, while the dimensions and
the surface sculpture appear to be alike in the two, the whorl section is
markedly distinct. This is evinced by the flat dorsum of the whorls and
the broad but low cast of the aperture in Sowerby's figure, and by McCoy's
statement1 that the section of each whorl is twice as wide as long. In the
specimens of T. alpheus from Shelby, the proportion of width to
hight is, in the inner volutions, as 3:2, in the ephebic volution however,
only as 5 : 4. This volution is, therefore, relatively much higher than in the
English form. In this character our material agrees fully with Hall's type
of T. alpheus. On the other hand, the single specimen which served
as representative of this species in Hall & Whitfield's description of its
occurrence in Ohio,3 possesses lower volutions, it being described as having
the lateral diameter of its whorls nearly double that of the dorsoventral

1 British Paleozoic Fossils, p. 309.
* Pal. Ohio, 2 : 145.

58 NEW YORK STATE MUSEUM

diameter. It is also much more widely umbilicated and the outer volu-
tions embrace the inner ones for about one half their width. As the
large series of New York specimens are quite uniform in their relatively
high volutions, it seems to us that the specimen from Genoa O., repre-
sents another type and approaches Trematonotus chicagoensis
McChesney, which (in its restricted definition) possesses only low volutions
and a very wide umbilicus.

Trematonotus alpheus is very nearly related to T. 1 o n g i-
tudinalis Lindstrom, which has cylindric volutions, a like surface orna-
mentation and an equal degree of umbilication. It differs however in hav-
ing a relatively much greater expansion of the lateral peristome and shorter
outer lip ; and T. alpheus does not exhibit the distinct dorsal ridge of
the outer lip in continuation of the slit band, and the corresponding sinua-
tion of the margin of the outer lip. Lindstrom regarded his species most
nearly related to T. trigonostoma Hall & Whitfield, evidently
because only incomplete casts of the more closely related T. alpheus,
had been figured at the time of his study.

The peculiar preservation of the majority of the specimens as molds is
evidently the same as in the Gothland material, for the principal figure given
by Lindstrom illustrates the same mode of preservation. Failure to prop-
erly interpret this figure led Koken to the misconception that it represents
the inside of the aperture, and he has stated,1 in his elaborate research
Ueber die Entwickelung der Gastropoden vom Cambrium bis zur Trias,
that Trematonotus has on the aperture internal folds, which show no rela-
tion to the outside sculpture. Our material shows how easily this miscon-
ception could arise. The wrinkled sculpture is actually that of the outside
of the aperture, and the inside of the aperture was nearly smooth.

We need not emphasize here the significance of the discovery of this
species in New York at a horizon corresponding to its occurrence in
Canada and Illinois. We fail to find the form cited among the Guelph
fossils of Wisconsin ; among the Racine fossils, however, there is listed

'Neues Jahrb. Beilagebnd. 1888-89. p. 386.

GUELPH FAUNA IN THE STATE OF NEW YORK 59

Bucania angusta1 (in error for angustata), which probably is a
synonym of T. alpheus, as stated above. Hall also2 mentions the
occurrence of Bucania angustata at Racine, stating that the speci-
men is indistinguishable from the species occurring at Gait. The early
appearance of this form in the Racine beds of Wisconsin seems to us quite
significant in view of the abundant appearance of T. alpheus in the
lower Shelby dolomite.

DIAPHOROSTOMA Fischer. I 885

Diaphorostoma niagarense Hall (sp.)

Plate 10, fig. 14-16

Platyostoma niagarensis Hall, Paleontology of New York. 1852. 2:287,
pi. 60, fig. i a— v

Two very young specimens from Rochester and four equally small
ones from the upper Guelph at Shelby, exhibit in profile, shape of volu-
tions, aperture and surface markings, the characteristic features of D.
niagarense. The largest of these specimens possesses a broad, shallow
depression on the middle of the body whorl, where the growth lines are
distinctly sinuate.

This form occurs in various exposures of the Rochester shale within
the State of New York, and also in more robust development at Waldron
Ind. It is not reported from the Guelph formation, nor has it been recog-
nized from the Coralline limestone of eastern New York.

POLKUMITA nom. nov.

In 1876 Munier-Chalmas introduced3 the generic term Oriostoma
(-Horiostoma) for certain French Lower Devonic shells which have been
more fully explicated by Oehlert and Barrois. Lindstrom," after com-
parison of the Gothland shells with the French species regarded both
congeneric, admitting however a dissimilarity in the abundant presence

'Geul. Wisconsin, 2:375.

"N. Y. State Cab. Nat. Hist. 2oth An. Rep't. 1867. p. 346.

3 Jour, de Conchyliologie, 16 : 103.

*The Silurian Gastropoda and Pteropoda of Gotland.

60 NEW YORK STATE MUSEUM

of opercula among the Swedish shells, which have not been observed
with typical species of Horiostoma — an argument to which little weight
can be given. Horiostoma, however, was described as having the final
whorl free about the aperture though only for a short distance, a feature
which is not specifically noted by Lindstrom for the Siluric species.
Koken has expressed1 the belief that there is a palpable difference in the
typical Horiostoma (H. konincki Oehlert) and the species referred by
Lindstrom to that genus, and regards the former as related to the capulids,
while the latter are derivable by easy stages from Euomphalus. Koken
has proposed to denominate the Swedish Horiostomas by the term Poly-
tropis de Koninck, introduced for Carbonic shells in 1881. As this name
however was employed by Sandberger in 1874 for an entirely different
group of Gastropods, its use is not permissible.

Koken has not made out a very forcible argument for the distinction
of these genera ; and our impulse is to array the species from the Guelph
which we are about to discuss, under Munier-Chalmas's genus. Admitting
however the dependability of Koken's inferences, there remains no place
here for the term Polytropis which he has applied to the Swedish species
and which Whiteaves, following that proposition, has also employed for
species of the Guelph of Ontario. Hence we have introduced the name
Poleumita, basing its characters as a genus on the species which is most
abundant in the Guelph horizon at Rochester, P. scamnata.

Poleumita scamnata sp. nov.

Plate Q, fig. 1-8, 10, 13-15

Shell turbinate, with spire more or less depressed, there being in this
respect a notable variation among the individuals ; whorls five to six, sub-
circular to subovate in section, very slightly overlapped by succeeding volu-
tions, on the contrary separated by a broad and deep suture, above which
the whorls stand up prominently. The form of the whorl does not vary
materially with growth, but the suture and its excavated or flattened outer
slope become more conspicuous though relatively no larger on the later

1 Neues Jahrb. fur Mineral. Beilageband 6. 1889. p. 425, 477.

GUELPH FAUNA IN THE STATE OF NEW YORK 6 1

whorls. Near the aperture the last whorl is distinctly free from the preced-
ing. Aperture circular, not thickened ; umbilicus round and deep. Surface
bearing a series of about 20 fine, elevated, flat topped and continuous ridges,
of which about 15 are on the outer and upper slope of the whorl. These
are separated, except near the suture, by flat grooves of subequal size and
wider than the ridges.

The excavated slope to the suture occupies the width of two or three
of these intervals, and on this faint traces of the revolving lines may some-
times be observed. On the umbilical surface the revolving ridges are more
prominent than elsewhere and more widely separated. At times these
ridges appear to be faintly grooved at their summits. All these ridges are
crossed by fine, imbricating or tilelike, concentric striae which are caught
back at the summits and are most sharply evident in the intervening fur-
rows. These lines are specially noticeable over the sutural slope where
they are faintly festooned by the obsolete revolving lines, and again toward
the umbilicus. At the aperture of adult shells they are closely crowded.

Dimensions. A typical example of the species measures as follows :
hight (apex to lower margin of aperture) 28 mm; basal diameter 31 mm,
i. e. a ratio in these dimensions of nearly i : i. Another example has a
hight of 20 mm, basal diameter of 35, a ratio of 4:7, indicating a very
depressed spire.

Observations. This beautiful species is the most common of all the
gastropods of the Rochester fauna, and also occurs in the upper horizon at
Shelby, but has not been found in the lower bed. All the specimens
before us indicate remarkable uniformity except in the degree of elevation
of the spire. The species is probably related to the shell Whiteaves has
identified with Euomphalus (I884),1 Polytropis (1895) macrolin-
eatus Whitfield, from the Guelph at Elora and Durham, Ont, but differs
therefrom in proportions of the whorls, depth of suture and apparently in
the character of the ridges of the surface. While we are unable to find
closer agreement in the Canadian and New York species, we are disposed

1 Op. fit. v. 3, pt i, pi. 3, fig. 6.

62 NEW YORK STATE MUSEUM

to believe that the former could hardly with safety be referred to the large,
very coarsely ridged shell which Whitfield described ' as Euomphalus
macrolineatus from the dolomites at Manitowoc Wis. In size and sur-
face characters P. scamnata approaches very closely Lindstrom's H o r i -
ostoma lineatu m,2 having the same sculpture throughout, but the
latter has its spire greatly depressed and the body whorl attached at
the aperture.

Poleumita (?) sulcata Hall (sp.)

Plate 10, fig. 1-4

Cyclonema sulcata Hall, Paleontology of New York. 1852. 2:347, pi. 84,

fig. la-d
Trochonema (Pleurotomaria) pauper Hall, New York State Cab. Nat.

Hist, zoth An. Rep't. 1867. p. 343, pi. 15, fig. 5, 6, 9

Cyclonema sulcatum Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i, p. 18,

pl- 3, ng. 5
Polytropis sulcatus Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 89,

pl. 13, fig. 9, 9a

The original of this species was a shell from the " Onondaga Salt
group, Newark, Wayne co., N. Y." With it were described other speci-
mens obtained by Professor Hall on his visit to the Canadian Guelph
localities in 1848. The early illustrations, which are not altogether satis-
factory for the requirements of identification among so many similar shells,
have been supplemented by the figures given by Whiteaves as above cited.
The species appears to be among the rarer gastropods of the Guelph forma-
tion, but in the Rochester material we find several examples of it, some of
them preserving the detail excellently, and we also have the same spe-
cies from the dolomites of the upper Guelph at Shelby. Whiteaves has
redescribed the species in full, and we find no pronounced disagreement
therewith among our shells. Characteristic of it are (i) the notable ele-
vation of the spire, which is considerably greater than the basal diameter

1 Geol. Wisconsin, 4 : 294, pl. 18, fig. 5, 6.

* Silurian Gastropoda, p. 173, pl. 20, fig. 42-44.

GUELPH FAUNA. IN THE STATE OF NEW YORK 63

and gives the shell the aspect of a true Cyclonema, (2) the deep suture,
with broadly excavated outer slope, (3) the differentials of the surface
sculpture, which over the body or outer convexity of the whorl consists of
fine, subequal, elevated, revolving lines, increasing by intercalation. Near
the suture two of these are stronger and wide apart, and on the umbilical
surface four are specially emphasized, being larger and more distant than
any of the rest. In all, the mature shell carries 20 to 25 revolving lines,
which are crossed by fine, crowded and rather indistinct concentric growth
lines, most palpable on the final whorl. The final whorl is apparently
slightly detached at the aperture as in P. s c a m n a t a, but the aperture
itself is not well retained in any of our specimens.

There is certainly very little difference in the characters of this species
as we now apprehend it and the shell figured by Hall as Trochonema
(Pleurotomaria) pauper from the Racine limestone at Racine.
There is a striking discrepancy between the description of that species and
its illustration which may be due wholly to the fact that the drawing was
made from material not accessible when the description was printed. S. A.
Miller,1 for reasons not evident, has ranked this species as a synonym for
Pleurotomaria halei Hall, but this is unquestionably erroneous.

Notwithstanding the resemblance of this shell to Cyclonema, we find
that it is kept from that association by the presence of a deep though nar-
row umbilicus, and perhaps also by the coexistence of opercula which
Whiteaves has discovered but which have not yet been recorded as occurring
in Cyclonema. The apparent detachment of the final whorl at the aperture
and the loose coiling evinced by the very deep suture in all these shells
constitute another difference from Cyclonema in which the whorls distinctly
embrace each other.

1 Cat. Paleozoic Fossils, p. 422.

64 NEW YORK STATE MUSEUM

Poleumita crenulata Whiteaves (sp.)

Plate 9, fig. Q, ii, 16-24

Straparollus crenulatus Whiteaves, Paleozoic Fossils. 1884. v. 3, pt 2,

p. 21, pi. 3, fig. 8a, b
Polytropis crenulatus Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 91

Dr Whiteaves states that he had but two specimens of this species in
the collections from the Guelph at Durham, and from these he drew his
description. In the Arey collection are upwards of 30 specimens, which
show that the species is specially characteristic of this eastern development
of the Guelph. About half as many have been collected in the lower
bed at Shelby but none at all obtained from the upper Guelph horizon,
where P. scamnata was found inconsiderable number. This abundant
material does not qualify the very clear and full description of the species
given by Whiteaves, which we here reproduce. Our larger series, however,
shows that wider variations exist in the elevation of the spire and surface
sculpture, as the few specimens from Durham would indicate.

Shell turbinate, compressed vertically, hight one third less than the
maximum breadth ; whorls three to four [5] ; spire short, about one third
the entire hight, somewhat conical, its volutions being obliquely rounded ;
suture excavated ; body whorl compressed vertically both above and below,
ventricose and inflated in the middle ; umbilicus about one third the diam-
eter of the base, very deep and exposing all the inner whorls up to the apex ;
mouth nearly circular but narrower above and very slightly emarginated or
indented by the penultimate whorl ; outer lip apparently thin and simple,
convex above and obliquely convex below. Surface marked by a few nar-
row and not very prominent spiral ridges which are crossed obliquely by
numerous flexuous crenulated raised ridges or lamellae. On the outer half
of the body whorl there are about seven or eight of these spiral ridges, four
above and either three or four below the middle. The upper ones, one of
which is placed very close to the periphery, are distant and rather clearly
defined, but the lower ones are close together and extremely indistinct.
These latter two are exclusively confined to the outer portion of the base,
and disappear altogether before reaching the umbilical margin. The crenu-
lated raised lines, however, which cross the whorls obliquely, are as strongly
marked in and around the umbilicus as they are on the central and upper
portions of the body whorl, and they are much more numerous as well as
more closely disposed than the spiral ridges.

GUELPH FAUNA IN THE STATE OF NEW YORK 65

While a few examples show the same ratio of spire to body whorl
(2 : 3) as that given by Whiteaves, many of the specimens from Rochester
have a decidedly more elevated spire, which sometimes nearly equals in
hight the diameter of the body whorl. The surface sculpture oscillates
between the entire development of the revolving ridges and the suppres-
sion of the transverse ridges, and the reverse, but mostly consists of quite
regular, coarse, sinuous and squamose transverse ridges.

Dimensions. An average well preserved shell has a hight of 30 mm
and a basal diameter of 39 mm.

Observations. There is no likelihood of confounding this with any
other described form. The general type of surface is of the same plan as
that of P. s c a m n a t a, but the sparseness of the revolving ridges and the
greater prominence of the concentric markings are pronounced. The
species is clearly of the same generic character as P. s c a m n a t a, but here
we fail to observe on any specimen evidence of the detachment of the
body whorl at the aperture.

COELIDIUM nom. nov.

Coelidium macrospira Hall (sp.)

Plate 7, fig. 2-8 ; Plate 10, fig. 13 •

Murchisonia macrospira Hall, Paleontology of New York. 1852. 2:346,

pi. 83, fig. 5
Murchisonia loganii Hall, Paleontology of New York. 1852. 2:346, pi. 84,

fig. 4a, 4b
Murchisonia macrospira Billings in Logan's, Geology of Canada. 1863.

P- 339, fig- 334
Murchisonia macrospira Nicholson, Paleontology Prov. of Ontario. 1875.

p. 70, pi. 3, fig. 9
Murchisonia macrospira Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i,

p. 27, pi. 4, fig. 7, ?a

Murchisonia logani Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 80
Murchisonia macrospira Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,

p. 81

In describing the fossils which he had collected from Gait and vicinity,
Professor Hall applied the name Murchisonia loganii to a turriti-

66 NEW YORK STATE MUSEUM

form specimen of the internal cast, showing in part the rounded whorls,
1 1 or 12 in number, and partly exposing the inner surface of the whorls.
At the same time he applied the name M. macrospira to an external
mold of moderately large size and of similar angle to M. 1 o g a n i i but pre-
senting whorls simply and rather sharply angulated by the peripheral slit
band. It has been questioned by Whiteaves whether any distinction
between such bodies can or should be made. On consideration of the
material representing these shells in the Rochester and Shelby collections,
in most cases clear cut internal casts present rounded whorls save in the
mature growth of the shell, such casts of the later volutions preserving the
angularity at the periphery. At times however this obscurity of angulation
on the cast is manifested on all whorls. It therefore seems probable that
but a single species is represented by these two names, and of these it is
M. macrospira which should be employed, as this is the name given to
the external mold on which the species characters are best expressed. The
species is represented by a number of specimens from Rochester, a large
example from the upper Shelby dolomite and several small specimens from
the lower horizon.

The illustrations here given show the angularity of the lower whorls,
on which the slit band stands out prominently at the periphery, being nar-
rowly convex, with elevated, thin margin not rising to the hight of the sur-
face of the band. Of the whorls, which may be 10 in number, the last four
show this angularity with increasing distinctness, but the earlier whorls
even when well preserved present only a rounded surface. The slit band
lies almost centrally on the whorl, but the overlap by later growth makes it
appear below the middle except on the final whorl. The slope on the upper
part of the whorl to the slit band is more direct and less convex than below.
The concentric surface lines slope directly backward about the periphery
but show a curvature on the umbilical surface. The apical angle is from
20° to 25°. The direction of the suture is quite transverse ; form of
aperture not observed. Umbilicus narrow but open to the apex of the
shell.

GUELPH FAUNA IN THE STATE OF NEW YORK 67

The term Coelocaulus was introduced by Oehlert in 1888 for Devonic
species of these Murchisonias ; and Murchisonia logani has, on
the basis of Hall's original figure, been referred to that genus by Ulrich.1
The name was however preoccupied by Hall for a genus of Bryozoa ;
but recognizing the usefulness of the distinction intended, we have sug-
gested the term here employed, Coelidium. Coelidium is pretty clearly
distinguished from forms referred to Hormotoma by the more depressed
whorls (when round), the less oblique suture and extended aperture and the
perforate axis.

Coelidium macrospira, originally described from the Guelph of
Ontario, has also been recognized among the fossils of the Guelph beds of
Wisconsin.

Coelidium cf. vitellia Billings

Plate 7, fig. 9, 10

Murchisonia v i t e 1 1 i a Billings, Paleozoic Fossils. 1865. i: 156, fig. 138

Murchisonia vitellia Nicholson, Paleontology Prov. of Ontario. 1875. p. 3,

fig. 6

Murchisonia v i t e 1 1 i a Whiteaves. Paleozoic Fossils. 1895. 7.3, pt 2, p. 80

In the material from Rochester is a single incrusted shell of a rather
large species of this genus with relatively short and stout spire presenting
an apical angle of 45° to 50°. Through the incrustation of the surface the
whorls show a low carination, and the vertical section which reveals the
open axis of the shell also indicates the angularity of the whorls at the
position of the slit band. This specimen bears six volutions. It is a shorter
and stouter shell than C. macrospira, and, of the various species of
Murchisonia with Coelidium characters which have been described from
the Guelph fauna, this approaches most closely to Billings's species M
vitellia from Gait, both in the angle of the spire and the number and
form of the whorls.

'Geol. Sur. Minnesota. Paleontology. 1897. v. 3, pt 2, p. 1019.

68 NEW YORK STATE MUSEUM

i

KOTOMABIA UlHch. 1 897

Eotomaria durhamensis Whiteaves (sp.)

Plate 10, fig. 17

Pleurotomaria durhamensis Whiteaves, Paleozoic Fossils. 1884. v. 3,

pt i, p. 24, pi. 4, fig. 2
Pleurotomaria durhamensis Whiteaves, Paleozoic Fossils. 1895. v. 3,

pt 2, p. 77

Two internal casts in a not very favorable state of preservation, the
larger composed of a spire of five whorls, have been found in the dolomites
of this horizon at Rochester and are referred to this species on account of
the slow increase of the whorls, the acuminate character of the apex, the
obliquely flattened upper side of the whorls and the indication of the for-
mer presence of a deep umbilicus. The description of P. durhamensis
was based on a single specimen, and that of P. gal ten sis, which is allied
to it but differs in its more depressed spire, on not many more ; Whit-
eaves has suggested that the former may prove to be only a variety of the
latter. The difference is however a persistent one.

This and the P. galtensis are here referred to the genus Eotoma-
ria, one of the divisions erected by Ulrich for forms heretofore comprised
under Pleurotomaria, a genus which, it is asserted by that author, when
restricted to forms agreeing closely with the original type is not found in

the Paleozoic.

Eotomaria areyi sp. nov.

Plate 8, fig. 2

This is a large and robust shell bearing somewhat the expression of
P. galtensis Billings,1 but its proportions are larger, stouter and distinct
in certain other details.

Shell depressed conic, broader than high, the thick spire being but
slightly elevated ; apical angle between 85° and 90° ; whorls five, increasing
slowly in size ; suture not deeply impressed, as the upper surface of the
whorls slopes gradually to the preceding ones ; but on the casts there is a

1 Geol. Sur. Canada. Paleozoic Fossils. 1862. i : 154, fig. 136. See Whiteaves, Pale-
ozoic Fossils. 1895. v. 3, pt 2, p. 75P pi. n, fig. 7.

GUELPH FAUNA IN THE STATE OF NEW YORK 69

deep furrow along the suture line. The upper slope of the early whorls is
moderately convex, but assumes a gently sigmoidal contour on the body
whorl, the upper part being gently convex, the lower concave, markedly so
directly above the slit band. This band forms a rather narrow groove with
projecting sides a little above the middle of the whorl ; on the casts it appears
as a quite prominent ridge, and passing on the spire a little above the suture
line. Periphery of whorls slightly convex, nearly vertical, umbilical surface
strongly convex ; umbilicus small, only about one sixth of the diameter
of the base of the shell ; surface marked by fine crowded growth lines,
which curve strongly backward at the slit band but on the under side con-
verge directly toward the umbilicus ; aperture not observed.

There is no satisfactory evidence of revolving ridges on the surface.

Dimensions. The best preserved example has a hight of 38 mm, basal
width of 47 mm. Another, an incrusted specimen, has a hight of 43 mm, a
basal width of 47 mm.

Our Rochester material has afforded but two examples of the shell,
which we find to differ from the still imperfectly known P. galtensis, not
alone in size, but also (i) in the thick and depressed spire, (2) in the profile
of the whorls, which are less acute than in P. galtensis and have a dif-
ferent curvature of surface, (3) in the distinct umbilication of the shell,
Whiteaves having stated that P. galtensis is imperforate. A still
more depressed and broader shell of apparently this group of species is
P. (Eotomaria)halei Hall1 from Racine Wis. and Bridgeport 111., and

1 See N. Y. State Cab. Nat. Hist. 2oth An. Rep't, p. 364.

70 NEW YORK STATE MUSEUM

in the opposite line of variation to an acuminate spire is P. (Eotomaria)
lap ham i Whitfield ' from the Niagaran at Ashford Wis.

Eotomaria kayseri sp. nov.

Plate 7, fig. i ; plate 8, fig. i

The presence of still another species of the genus in the Guelph of
Rochester is indicated by two internal casts, one of them pretty well pre-
served. These are of relatively large size, with stout whorls, apical angles
about 75°, spire elevated, three whorls preserved. The suture is deeply
impressed, the whorls overlapping not quite to the periphery. Surface of
the whorls full, expanded, prominent on the slit band, which is narrow
and elevated and bounded above by a similar ridge in close juxtaposition.
On the outer whorl the surface slopes rather directly from suture to periph-
ery or may be slightly concave between the peripheral ridge mentioned
and another low ridge just outside of the suture. The lower or basal
surface is evenly and moderately convex, not ventricose. The exposed
parts of the earlier whorls are quite regularly convex, though showing
evidence of the revolving ridges. The shell appears from the cast to have
been distinctly umbilicate, though the umbilicus is quite narrow.

The hight of the best preserved shell (allowing for the apical whorls)
is 53 mm ; width across the base 48 mm.

Eotomaria galtensis Billings (sp.)

Plate 10, fig. 10-12

Pleurotomaria galtensis Billings, Paleozoic Fossils. 1862. 1:154, fig. 136
Pleurotomaria galtensis Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,
p. 75, pi. ii, fig. 7

Specimens referable to this species, were collected in the upper and
lower Guelph of Oak Orchard creek.

Both show the characteristics of the internal and external casts on which
Billings based the description of his species, viz depressed conic profile
corresponding to an apical angle of about 100°, nearly flat upper side of

"Geol. Wisconsin. 1879. 3:296.

GUELPH FAUNA IN THE STATE OF NEW YORK "Jl

the volution, angular margins and the rather depressed lower side. The
impression of the exterior verifies the observation of Whiteaves as to the
external characters of this species and exhibits a nearly flat or only very
gently convex upper slope, a vertical carination near the base of the upper
whorls and a slit band, appearing as a spiral ridge which is concave on the
apical and convex on the umbilical side. A difference from the exterior
view given by Whiteaves exists in the position of the slit band, which lies
below the mid-hight of the last volution. In the original drawing by
Billings it lies at mid-hight, so that there is evidently slight variation of
this feature. The surface is described by Whiteaves as having been appar-
ently smooth ; the specimen in hand shows only faint recurving growth
lines on the shell fragments of the upper side of the whorls.

LOPHOSPIRA Whitfield. 1886
Lophospira bispiralis Hall (sp.)

Plate 10, fig. 6-9

Pleurotomaria bispiralis Hall, Paleontology of New York. 1852. 2:348,

pL 84, fig. 2a, 2b
Pleurotomaria bispiralis Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,

P- 74

This species was described from a single specimen obtained by Profes-
sor Hall at Gait ; and Whiteaves reports that it is not otherwise known
except in the reidentification of the species by Billings. The recorded
examples are known to be poorly preserved, but the original, which was an
external mold, shows quite distinctly features presented by three very good
examples from the Rochester localities. The original description of the
species is as follows : " Volutions about four or five, rapidly increasing from
the apex, subangular, and marked above and on one side by thin, sharp
carinae or spiral elevated lines." It is evident, on comparison with the
better material in hand, that the spiral elevated lines here referred to repre-
sent the narrow slit band, which is very prominent on the periphery. The
early whorls bear a sharp keel halfway between the suture and periphery,
but on the final whorl this becomes quite obsolete. Present material allows

72 NEW YORK STATE MUSEUM

a more precise definition of the characters of the species than could be
given by its author.

Diagnosis. Shell of medium size, turbinate conic, a little higher than
broad ; spire elevated, hight greater than the basal diameter of the body
whorl ; apical angle 60°, base imperforate (?) ; suture deeply impressed,
increasing outward in obliquity ; earlier whorls overlapped by the later for
one half the interval between the slit band and the base ; volutions about
five, subangular, slit band narrow with elevated margins, at or just above
the middle of the whorl. The body whorl has a gently convex, almost
direct slope from the suture to the slit band, but is convex and subventri-
cose below the periphery. On the earlier whorls the depression of the
upper surface is more pronounced, and the concavity is divided by a sharply
developed keel or single ridge. A narrow, rather obscure and nearly vertical
band runs along the suture. Surface marked by fine, irregularly concentric
lines which cross the carina without interruption but are directed backward
and are caught up at the slit band. On casts the carina and the slit band
are indicated by rather low, rounded ridges.

Aperture unknown.

Observations. The angularity and prominence of the whorls in this
species show its close approach to forms of Murchisonia having the expres-
sion of M. hespelerensis Whiteaves, and in this respect it is in har-
mony with Pleurotomaria durhamensis, these two species
differing chiefly in the degree of elevation of the spire.

Besides the larger specimens from Rochester six smaller ones were
obtained from the lower Shelby layer, and these distinctly exhibit the keel
of the upper side of the whorl and the spiral elevated lines of the slit
band. The upper Shelby dolomite has furnished no examples of the
species.

HORMOTOMA SaltCr. 1859

Hormotoma whiteavesi sp. nov.

Plate 8, fig. 5-9

Shell long, slender, terete and acuminate, its entire length being
nearly four times the diameter of the body whorl. Apical angle- i8°-2O°.

GUELPH FAUNA IN THE STATE OF NEW YORK 73

Volutions 9-10. These are but slightly overlapped, their exposed surfaces
thus being quite regularly convex ; the upper slope is slightly flattened or
depressed to the obscure slit band. The sutural slopes are deep, the suture
itself narrowly impressed, the edge of the lower whorl being slightly
depressed against the whorl above. Umbilicus covered. Aperture oblique
or subfusiform in outline. Inner lip somewhat thickened, outer lip with a
deep linguiform emargination at its upper third. This is the edge of the
slit band, which is a gently depressed sulcus without sharp margins, at which
the surface lines are bent deeply backward. This band is evident on all
whorls even on internal casts as an obscure flattening modifying the contour
of the shell. The surface bears a multitude of fine and crowded, somewhat
irregularly concentric lines, which are profoundly reflexed at the slit band
but seem to be continuous over that area. On the lower slope of the body
whorl is evidence of a second revolving band, which does not, however, effect
any change in the direction of the concentric growth lines. This is a feature
which is well defined only in a single specimen other examples, whether
exteriors or internal casts, not showing it.

Dimensions. The most complete example before us has a length of
85 mm, a width at the base of 28 mm. A large specimen, incomplete
at the apex, had a probable length of 100 mm and a basal diameter of
30 mm.

Observations. This graceful and striking species is one of the most
abundant organisms in the Guelph horizon at Rochester. The Arey collec-
tion contains 25 or 30 specimens which are either internal casts in white
chert or retain the shell more or less completely in pulverulent white silica
with dolomitic interiors. The species has also been obtained in the upper
Shelby horizon.

Shells of similar character to this have been already described from the
Guelph fauna. Dr Whiteaves has given figure and description ' of an
internal cast having similar outline and contour to H. whiteavesi though
of smaller size, and this he has identified with the Loxonema magnum

1 Paleozoic Fossils'. 1884. v. 3, pt i, p. 17 ; 1895. pt 2, p. 87.

74 NEW YORK STATE MUSEUM

Whitfield from the Guelph dolomites of Carlton township, Wisconsin.1 This
so called Loxonema, however, is a species of large proportions (Whitfield
states that the probable length estimated from the two whorls which consti-
tute the original specimen was fully 8 inches), rather square shouldered
whorls and so far as known, smooth surface. The fine preservation of the
Rochester specimens does not justify the reference of them to either Loxo-
nema or to this species provided it prove a Loxonema. We have little
doubt that the Guelph shell figured by Whiteaves (specimens are from Gait,
Hespeler and Elora) as Lox. magnum is specifically identical with, if
smaller, than the New York specimens of Horm. whiteavesi, and we
propose therefore the change of name here adopted, taking however as the
type specimens of the species those we have here figured.

The generic term Hormotoma which was introduced by Salter for Mur-
chisonias of terete form and rounded whorls has been quite generally placed
by authors back among the synonyms of Murchisonia. Lindstrom so treats
it and at the same time employs the term Loxonema for shells in which
among the longitudinal sinuous lines are extremely fine and crowded.

MACROCHILINA Bayle. 1 88o
Macrochilina sp. indet.

Plate 10, fig. 18

This is a very diminutive shell from the Rochester Guelph, with sub-
equally rounded oblique whorls, three in number, the last rapidly increasing
in hight, but all relatively narrow. In these respects it is unlike the various
species described (mostly by Billings) as Holopea from various Canadian
localities of the Guelph. The surface so far as preserved appears to be
smooth and without slit band.

1 Geol. Wisconsin, 4 : 317, pi. 24, fig. i.

GUELPH FAUNA IN THE STATE OF NEW YORK 75

TROCHONEMA SaltCF. 1859

Trochonema cf. fatuum Hall

Plate 10, fig. 5

Trochonema (Eunema) fatua Hall. N. Y. State Cab. Nat. Hist. 2oth An.
Kept. 1867. p. 345, pi. 15, fig. 7, 8

The upper Shelby dolomite has afforded a single imperfect example,
comprising parts of the ultimate and penultimate whorls which bear the
expression of the species cited above, showing a very broad peripheral
band with raised margins and somewhat depressed surface, a direct slope
above this band which is about as wide as the band itself, and a gently con-
vex surface beneath. Faint concentric lines may be seen on the surface of
this cast.

The original of this species is described from the Racine dolomites at
Racine Wis. It is also cited1 as occurring in the Guelph at Cedarburg
Wis., but it is not recorded in the Canadian Guelph.

BUOMPHALU8 Sowerby. 1812
Euomphalus fairchildi sp. nov.

Plate 8, fig. 3, 4

Shell of medium size, discoidal, with the apex of the spire depressed
below the summit of the body whorl and lying almost in a horizontal plane.
Volutions four to five ; all in contact, but no impressed zone is formed,
and at or near the aperture the body whorl seems to become almost
detached. On the cast these volutions are free. Whorls oval in section,
one third higher than wide ; outer slope depressed convex and broad, upper
side obscurely subangular, lower more broadly rounded ; aperture appar-
ently oval, not thickened, with a broad emargination on the upper side ;
umbilicus wide, exposing all the whorls.

Surface covered with sharp and fine, rugose concentric lines, which
curve forward over the broad peripheral surface of the whorls and make a

•Geol. Wisconsin, 2:380.

76 NEW YORK STATE MUSEUM

rather sharp and deep retral curve at the summit of the whorl, indicating
the position of the apertural notch.

Dimensions, Two specimens, both of which were collected at Roches-
ter, have a greatest width of 38 mm, and the body whorl near the aperture
has a hight of 1 8 mm.

Observations. No species of similar habit and expression has been
described from the Guelph fauna. Billings's two species, Straparollus
h i p p o 1 y t a and S. daphne, from the dolomites at Gait are small shells
with elevated spires ; S. m o p s u s Hall1 from the Racine limestone at Racine
is smaller and has cylindric volutions ; its surface markings are not known ;
S. niagarensis Hall & Whitfield2 has revolving ridges on the whorls.
The resemblance of the species is however extremely close to certain
expressions of E. gotlandicus Lindstrom.3 Lindstrom has maintained
that individuals of a given species of Euomphalus may have their whorls
contiguous throughout or be evolute in varying degree. Hence to this spe-
cies, E. g o 1 1 a n d i c u s, he has referred a series presenting all phases in
the unwinding of the whorl, thus embracing within the same species the
conditions typical of both Euomphalus and Eccyliomphalus. With the
involute expression of this species the agreement of E. f a i r c h i 1 d i is so
close as fully to justify identification were the evolute condition of the
species eliminated, for this is not expressed in any of the specimens before
us. We are however disposed to follow Lindstrom's valuation of the genus
Euomphalus and have hence employed the designation in preference to Mr
Ulrich's equivalent construction of the later term Eccyliomphalus and the
common and freer employment of Straparollus, in which the whorls are
impressed and the evolute condition less complete.

Named for H. L. Fairchild, professor of geology, University of
Rochester. /

'N. Y. State Cab. Nat. Hist. 2oth An. Rep't, p. 342, 'pi. 15, fig. 21, 22.
'Pal. Ohio. 1875. 2:144-

3 The Silurian Gastropoda and Pteropoda of Gotland, p. 139, pi. 13, fig. 19-31, spe-
cially fig. 20-22

GUELPH FAUNA IN THE STATE OF NEW YORK 77

CEPHALOPODA

ORTHOCERAS Breyn 1732
Orthoceras trusitum sp. nov.

Plate 10, fig. 25, 26 ; plate 13, fig. i-xo

Shell straight, thick, regular, slender, tapering at an angle of 10° ; of
moderate size, diameter of largest fragment 38 mm, transverse section cir-
cular or subelliptic. Septa closely arranged, regularly and moderately con-
cave, their depth approximately equaling that of the camerae ; about 6 mm
distant at the largest diameter, 3 mm distant when the shell has a diameter of
25 mm, 2.2 mm when the latter is 15 mm and about i mm at the apical end.
The sutures are not straight, have a broad saddle on the ventral side but
on the opposite side are nearly transverse. Siphuncle very small (3 mm
where the diameter of the chamber is 26 mm), tubular and ventrocentren.
The living chamber shows the same degree of tapering as the septate por-
tion of the shell. The aperture has not been observed. The surface is
usually entirely smooth, but when well preserved shows a very faint and
fine longitudinal striation. In the largest specimen observed these lines
are 1.5 mm apart and consist of broad flat ridges with narrow furrows
between.

One of these specimens was labeled by Mr Arey, Orthoceras sel-
wyni Billings. This is probably the specimen so listed in the provisional
enumeration of fossils given by the discoverer. While it is true that the
specimens under consideration have the same apical angle and depth of
camerae as Billings's measurements of that species indicate, the siphuncle of
O. s e 1 w y n i is moniliform, with discoid inflations between the septa, and
lies at a short distance from the ventral margin. According to Whiteaves
the original specimen of this species is a very imperfect cast and the species
therefore incompletely characterized.

There is some justification for comparing these specimens to O. s c a m-
m o n i McChesney. The somewhat complicated synonymy of this form
given by Whiteaves shows that it has passed under various names, as

78 NEW YORK STATE MUSEUM

O. columnare and O. angulatum Hall, and has even been described
under four different names by McChesney himself. A comparison with
the descriptions and figures given by these authors indicates that that
shell has the same rate of tapering as O. trusitum and the same
small cylindric ventrocentren siphuncle. The septa show about the same
convexity but in all the figured specimens are farther apart than in
O. trusitum.

The surface sculpture of O. angulatum and O. scammoni is
described as consisting of angular, equidistant, longitudinal ribs about one
line distant when the shell is an inch in diameter. Such ribs are not
observable in any of the New York specimens.

In the collection from Rochester is a single short fragment which
has a much slower rate of tapering (6°), the siphuncle is relatively large
and only i mm distant from the ventral margin at a diameter of 8 mm,
and the septa are very closely arranged, 1.5 mm apart at the same diameter.
It is possible that this specimen represents the apical part of O. selwy n i,
though there is too little known of this specimen on the one hand and that
species on the other, to assert the identity positively.

Orthoceras trusitum is represented by a large number of
fragments (upward of 30) from the Rochester Guelph and is of relatively
frequent occurrence in the lower Shelby dolomite. In the upper Shelby
bed it is rarer.

Orthoceras rectum Worthen

Plate 12, fig. 9

Orthoceras rectum Worthen, Geology of Illinois. 1875. 6: 504, pi. 26, fig. 3
Orthoceras crebescens Hall & Whitfield, Geology of Ohio. 1875. 2:148,
pi. 9, fig. 2

Worthen's original description of this species is the following :

Shell of medium size, very gradually tapering, septa moderately con-
cave, two of the intervals being a little less in width than the diameter of
the shell. Length of specimen with 12 septa preserved, 8.87 inches, length
of outer chamber about 3 inches. Surface markings and siphuncle
unknown.

GUELPH FAUNA IN THE STATE OF NEW YORK 79

This shell seems to be nearly related to O. crebescens of Hall,
but differs from that species in its much less tapering form, and in the
proportional width of the septa.

Worthen gives "the Niagara limestone " of Joliet 111. as horizon and
locality of his species.

Before us is a fragment retaining 10 camerae from the lower Shelby
bed, which differs from the associated O. crebescens in the same
respect as indicated above for O. rectum. It expands so slowly that its
apical angle is only about 5°, and the camerae are so deep that the
diameter is but a little larger than the combined depth of three camerae.
While the latter are therefore still somewhat shallower than those of the
type specimen of O. rectum, the difference is so small that it is well
within the limits of individual variation. The section of the Shelby species
is subcircular, and the siphuncle is centren.

In the same year in which Worthen differentiated O. rectum from
O. crebescens, Hall and Whitfield described and figured a specimen
from the "limestones of the Niagara group" at Cedarville O., which they
referred to O. crebescens, but which, in the differential characters cited
above, tallies quite closely with the lower Shelby specimen. Hall and
Whitfield also noted the difference in the depth of the chambers between
the Ohio and the original Wisconsin specimens of O. crebescens, but
did not consider it sufficient for separation. The additional difference in
the rate of expansion brought out by the figure of the Ohio specimen and
its description, in which it is said to taper " gradually and moderately,"
while the types of O. crebescens are stated to taper " rapidly," seems
to have been overlooked in the comparison of the forms. The constancy
of the combined appearance of these differences in the Illinois, Ohio and
New York specimens and the very distinct habit resulting from them, fully
warrant their recognition as of specific importance.

SO NEW YORK STATE MUSEUM

Orthoceras crebescens Hall

Plate 10, fig. 24, 27, 28 ; plate n, fig. 2-5

Orthoceras crebescens Hall. N. Y. State Cab. Nat. Hist. 2Oth An. Rep't.

1867. p. 354, pi. 19, fig. 1-3
Orthoceras crebescens Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i,

P- 37

Orthoceras crebescens Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,
p. 98

Not Orthoceras crebescens Hall & Whitfield. Geol. Sur. Ohio. Paleon-
tology. 1875. v- 2i Pt 2> P- r48, pi. 9, fig. 2

Among the orthocerata of the lower Shelby dolomite is a small group
of specimens which contrast with the others by their large dimensions, and
specially the greater depth of the chambers. These must be the relics of
the giants in the cephalopod fauna that populated the lower Guelph coral
reef. They are all casts of the interior.

Diagnosis. Conch straight, thin, of large size, the living chamber of
one specimen attaining a diameter of about 70 mm, gradually expanding
(angle 9°), cross section circular or subcircular ; surface smooth, faintly
striated longitudinally ; sutures transverse with a distinct (ventral ?) lobe,
camerae very deep, the sutures lying 9 mm apart in one specimen where the
conch has a diameter of 40 mm, and in another where the diameter is 50
mm ; septa evenly concave and very deep, the depth being about equal to
the depth of the camerae ; siphuncle centren or nearly so, large, nummuloidal
in the mature stage, where it passes the septum, about one sixth the diame-
ter of the conch ; living chamber possessing the same rate of expansion as the
septate portion, repeatedly slightly constricted ; aperture apparently nearly
straight. One cast retains faint longitudinal ridges, with flat interspaces.

Horizon. Lower Shelby dolomite. No specimens have been obtained
in either the upper bed at Shelby or Rochester.

Our material agrees in all essential features with the type specimen
described by Hall from the Racine limestone, Wisconsin. In vol. 2,
Geology of Wisconsin, the species is listed as occurring in the Waukesha,
Racine and Guelph beds ; in the Racine beds at the greatest number of

GUELPH FAUNA IN THE STATE OF NEW YORK 8 1

localities, so that we may conclude that it reached its acme there and sur*
vived only sparsely in the Guelph, where it has been found occasionally at
Hespeler and Elora, though in greater number in the lower Shelby dolomite.
The series of orthoceracones from the lower Shelby bed contains a
fragment, consisting of seven chambers, which appears to be a portion of
the apical part of the conch of O. crebescens, which has hitherto not
been observed. It agrees with that species and differs from the other asso-
ciate orthoceratites by its slender form, very deep camerae, their depth
being nearly half the width of the conch, and the very large siphuncle,
which occupies nearly half the interior space of the conch. This siphuncle,
however, is but very slightly expanded, and the cast of the siphuncular
cavity is completely cylindric. As the siphuncle of other species is known
to become nummuloidal only in late growth stages, the difference between
the siphuncles of this small conch and those of the large conchs of O.
crebescens is not thought to militate against a reference of the same

to that species.

DAWSONOCERAS Hyatt. 1883

Dawsonoceras annulatum Sowerby, var. americanum Foord

Plate 10, fig. 19-21 ; plate n, fig. i

Orthoceras annulatum Sowerby var. americanum Foord, Cat. Fossil
Cephal. British Museum. 1888. p. 56, 57

The wide variation in the expression of the ornament among specimens
which have been referred to O. annulatum Sowerby and have likewise
been described under a variety of other names, now renders exceedingly
difficult the accurate determination of specimens of this type, specially
when the species are represented by only fragmentary parts. It is evident
from the study of the long list of annulated orthoceracones of the late
Siluric, and has been specifically pointed out1 by one of the writers in the
case of certain lower Siluric shells of similar type, that the ontogenic
progress of the ornament in the annulate and longitudinally striate shells is
quite uniform, and it may be summarized thus : The annuli are a quite

1 Minnesota Paleontology, v. 3, pt 2, p. 787.

82 NEW YORK STATE MUSEUM

primitive feature appearing in the early growth stages (cf. K i o n o c. d a r-
w i n i) with their greatest relative strength. With continued shell growth
they become broader, less distinct and in progressed shells entirely obsolete
even before adult growth is attained. The longitudinal lines, however,
which develop before the early annuli, remain with the obsolescence of the
latter, for a time the principal feature of the exterior. Contemporaneous
with both of these surface features there develops a concentric lineation,
which also may become more conspicuous with the suppression of the
annuli, in some species becoming a prominent cancelating feature, even
entirely replacing the longitudinal ribs. Among species which have been
described from the American Upper Siluric the following express vari-
ous conditions of this combination of surface characters : O. u n d u -
latum Hall, O. annulatum Sowerby var. americanum Foord,
O. medullare Hall, O. nodocostatum McChesney, O. cadmus
Billings, O. virgatum Sowerby, O. 1 a p h a m i McChesney. This state-
ment does not impugn the differential specific values of certain of these
forms, but, as all of them have been described from incomplete cones, it is
clearly impossible with present knowledge to decide on the specific values
involved. Generic characters among these late Siluric species are conse-
quently highly obscured and uncertain, and the genera of this group pro-
posed by the late Professor Hyatt pass into each other, as do the specific
characters. Hyatt has proposed to term species which retain the annuli
throughout growth with concentric undulating lines or frills, Dawsonoceras
(D. annulatum Sow. — O. undulatum Hall). Shells having the
longitudinal ridges conspicuous and obscure annuli in senile growth are
termed Kionoceras ; a condition in which the annuli of early growth become
later obscured, with corresponding increase in the prominence of the longi-
tudinal lines, are Spyroceras, while a development of spines or nodes at the
intersection of annuli and longitudinal ridges constitutes the character of
Thoracoceras.

We find among the material from Rochester several small specimens
of sharply annulate cones which we refer to Dawsonoc. annulatum

GUELPH FAUNA IN THE STATE OF NEW YORK 83

var. americanum Foord, employing that author's distinctive designation
for American expressions of Sowerby's specimens. These specimens doubt-
less represent early growth stages; one has 15 sharply developed somewhat
sinuous annuli in a length of 23 mm, another 10 in a length of 16 mm, a
third 24 in a length of 45 mm. The annuli are separated by rather deeply
concave depressions not always of equal width. Fine sharp longitudinal
striae, often clearly in two series, cross the surface, and these are cancelated
by much finer and obscure concentric lines. Nothing that would indicate
the modification of those characters in later growth has been observed.
Several large specimens, exceeding an inch in diameter and possessing
strong, rounded annulations, were obtained from the lower Shelby bed.
None were found in the upper horizon.

Dr Whiteaves has reported the presence of this species in the Guelph
at Hespeler and Elora, where it seems to be rare and the surface characters
are not specially noted. It is also cited in the Geology of Wisconsin among
the Racine and Guelph fossils. Professor Hall ' knew it only from the
lower beds at Waukesha and near Wauwatosa, Wisconsin. Its occurrence
at Yellow Springs and Cedarville O., is recorded by Hall and Whitfield in
Paleontology of Ohio, 2: 148. It is therefore evident that this species rises
from the lower Niagaran shales, where it is most common, into and through
the higher Niagaran beds in New York as well as in the west.

Orthoceras bartonense is a shell from the Barton beds or
highest member of the Niagaran series at Hamilton Ont., which has been
described by J. W. Spencer* as distinct from D. annulatum in having
the annular crests marked " by swelling waves (giving a nodular appearance
on the margin)." This is the same variation which McChesney described
as O. nodocostatum3 but which Hall seems to have correctly esti-
mated 4 as identical with O. annulatum.

1 N. Y. State Cab. Nat. Hist. 2oth An. Rep't, p. 351.

2 Mus. Univ. Missouri. Bui. 1884. 1:60, pi. 7, fig. 7.
J Descr. Paleozoic Fossils. 1860. p. 94.

< N Y. State Cab. Nat. Hist. 2oth An. Rep't. expl. pi. 20.

84 NEW YORK STATE MUSEUM

KION-OCKKAN Hyatt. 1883
Kionoceras darwini Billings (sp.)

Plate 10, fig. 22; plate n, fig. 6; plate 12, fig. 1-8

Orthoceras darwini Billings, Paleozoic Fossils. 1862. i : 161 (not figured)

Cyrtoceras myrice Hall & Whitfield, Geol. Sur. Ohio. 1875. v. 2, pt 2, Pale-
ontology p. 149, pi. 8, fig. 9

Orthoceras darwini Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i, p. 38, pi. 6,
fig. 2, 2a

Cyrtoceras myrice Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i, p. 39, pi. 6,

fig- 3, 3*
Orthoceras darwini Foord, Cat. Fossil Cephal. British Museum. 1888. pt i,

P- 7<>, fig. 8
Orthoceras darwini Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 100

Among the Rochester specimens of this species is one which is
excellently preserved and shows the surface features probably better
than any which have been recorded. There are sharp, angular, longi-
tudinal ridges, between each pair of which normally lies a smaller
ridge. These ridges of the first and second order are separated by equal
furrows. Concentric lineation does not appear on this specimen but is
shown on the later growth of a larger individual. Toward the apical end
of the shell are quite well marked transverse annulations. These, as in
many other species of this generic type, are completely obscured in later
growth. The gentle cyrtoceran flexure of the cone is clearly indicated in
the best of the specimens. The sipho is subcentral and the section is nearly
circular, with the concave side slightly flattened.

No examples of this pretty and characteristic species have been
obtained in the upper Shelby bed, but the lower dolomite has fur-
nished a number of well preserved specimens, two of which are remarkable
for their dimensions, which indicate a size considerably larger than hitherto
recorded. One of these is preserved as a mold of the exterior and attains
a length of 158 mm, with both ends imperfect. This retains the same
slight curvature exhibited by the smaller specimens. Another is a cast of
the interior of the living chamber and of 10 septa, which shows but very

GUELPH FAUNA IN THE STATE OF NEW YORK 85

slight curvature and traces of the longitudinal surface ornament. This
specimen shows a marked gerontic character in the uniformly closer
arrangement of the last septa and therefore furnishes an indication of the
mature size reached by this species. Its living chamber has a diameter of
48 mm and a length of 51 mm. The aperture is partly preserved and
appears to have been slightly curved. The chambers show the same depth
(about 5 mm) as in Billings's type specimen of Orth. darwini, the
conchs of both having a like width. The sutures have a broad, low saddle
on the concave side. While two of the smaller specimens bear only uniform
longitudinal ridges, the larger conch is provided with low annulations
throughout its entire length. In the best preserved young specimens from
the Rochester Guelph these annulations appear only in the earlier stages,
and it thus appears that the large individual preserved this infantile charac-
ter into the ephebic stage. The three factors of the surface ornamentation
follow evidently in the same order as observed by Clarke in annulated and
lineated Trenton forms and above referred to, viz longitudinal ribs, annula-
tions, transverse striae, but with this difference, that the annulations here
never attain any strong development and soon disappear, while the longi-
tudinal ribs appear to persist throughout life and become in the ephebic
stage complicated with the concentric lineation, which, however, does not
attain such prominence as in the mature stage of Dawsonoceras
annulatum or in the Trenton forms mentioned.

Dr Whiteaves gave the first illustration of the original of K. darwini
and points out its identity with Hall & Whitfield's Cyrtoceras myrice
described at a later date from the dolomites at Yellow Springs O. Billings's
original was from the Guelph at Hespeler, and other specimens originally
identified by Dr Whiteaves with Cyrtoc. myrice are from Durham.
This species is, hence, to be considered a typical Guelph form. Its connec-
tion with the longitudinally ribbed or cancelated, slender orthoceratites, so
common in the Racine beds whence it probably descended, is very close,
specially with Orthoceras angulatum (Wahlenberg) Hall,1 which is

1 N. Y. State Cab. 2oth An. Rep't. 1867. p. 353.

86 NEW YORK STATE MUSEUM

described as possessing the same number of longitudinal ribs within the
same space, the same cancelation in some parts, but has somewhat deeper
camerae, tapers slightly faster and is perfectly straight. This species is said
by Hall to be identical with the numerous species of longitudinally ribbed
Racine forms erected by McChesney, and also with Hall's O. v i r g a t u m (?)
and O. cancellatum from the Rochester shale of New York. Whiteaves
identifies the latter species with Orthoceras cadmus Billings, which
has been described from the Niagaran at Grimsby Ont.

Kionoceras medullare Hall (sp.)

Plate 10, fig. 23

Orthoceras medullare Hall, Geol. Sur. Wisconsin. Report of Progress. 1859.
Orthoceras medullare Hall, N. Y. State Cab. Nat. Hist. 2oth An. Rep't. 1867.

P- 353, pl- 20> fig- !, 2
Orthoceras m ed u 11 are (?) Meek & Worthen, Geol. Sur. Illinois. 1875. 6:504,

pl. 26, fig. i
Orthoceras medullare Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i, p. 37

This species is represented in our collections by a single mold of the
exterior from the lower Shelby dolomite. The ornamentation of this
fragment, which belonged to a conch having a diameter of about 30 mm,
consists of sharp, longitudinal striae, alternately stronger and finer ; these
are crossed by transverse lines, arranged slightly closer than, and equal
in prominence to, the finer, longitudinal striae. Seven of these longi-
tudinal lines may be counted in 10 mm. The character of this ornamenta-
tion, the relative distance and strength of the striae, is that ascribed to
O. medullare, and we, therefore, provisionally identify the Shelby
species with that.

Hall described Orth. medullare from "limestone of the Niagara
group at Waukesha and Wauwatosa, Wisconsin." In the lists of fossils of
Wisconsin, given in Geology of Wisconsin, v. 2, K i o n. medullare is
cited only from the Waukesha and Racine beds, but not from the Guelph.
Meek and Worthen doubtfully refer to the species a specimen from the
Niagara at Joliet 111. Whiteaves reports the species in the Guelph at
Elora Can.

GUELPH FAUNA IN THE STATE OF NEW YORK 87

Cyrtoceras arcticameratum Hall

Plate 15, fig. i, 3; plate 16, fig. 1-7

Cyrtoceras arcticameratum Hall, Paleontology of New York. 1852. 2:349,

pi. 84, fig. ?a-d
Cyrtoceras arcticameratum Billings, in Logan's Geology of Canada. 1863.

P- 34°
Cyrtoceras arc ti earner at um Whiteaves, Paleozoic Fossils. 1895. v. 3, pt a,

p. 103

This species was very briefly characterized by Hall in the following
words : " Elongated, slender, gradually tapering and gently incurved ; septa
numerous ; slightly convex ; section transversely oval, siphuncle dorsal."
The original specimens from Gait were not very good. Billings cites Gait
and Hespeler as localities, but Whiteaves states that he has seen no speci-
mens of the species. It has also been recognized in the Guelph at Cedar
burg Wis.1

In the Rochester material there are several examples, one of excellent
quality, which present characters agreeing with Hall's diagnosis and figures,
and these are specially marked by their long, slender and gently arcuate
cones, in which the outer ventral curve is about 87° and the inner 69°. The
section is nearly circular in early growth but later becomes broadly oval.

The living chamber is long, somewhat swollen in the middle, broadly
contracting to the aperture, which has straight lateral margins. Septa
from 2 to 3 mm apart, slightly concave and nearly transverse, broadly
flexed forward ventrally. Siphuncle small and ventral.

Surface smooth, only fine concentric lines being visible. These become
squamous toward the aperture and all recurve ventrally at the hyponomic
sinus.

Dimensions. The most complete of these examples has a length meas-
ured on the outer curve of 95 mm. This covers most of the living chamber,
which is 29 mm long. Width of living chamber dorsoventrally 21 mm, of
aperture 16 mm, of lower end of specimen 9 mm.

'Geol. Wisconsin, 2:380.

88 NEW YORK STATE MUSEUM

Cyrtoceras erodes Billings

Plate 15, fig. 3-n

Cyrtoceras orodes Billings, Paleozoic Fossils. 1865. i : 162 (not figured)
Cyrtoceras orodes Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 103, pi. 14,

fig- 7-9

Several specimens of this species presenting a very slightly curved and
rapidly tapering shell with nearly circular section, have been obtained from
the lower Shelby horizon and at Rochester. The original, which was not
figured by Billings, and two specimens of better preservation have been
described and figured by Whiteaves.

The New York specimens are of moderate size, tapering rapidly (one
increasing from n to 19 mm in 39 mm; another from 12 to 28 mm in 60
mm), very gently curved, of nearly circular section, becoming somewhat
flattened dorsoventrally in late growth. Billings describes the dorsoventral
diameter as being slightly the greater, which is true of earlier growth, while
the outline of the section of the type specimens given by Whiteaves is cir-
cular. The septa are closely arranged; in the smallest specimens from 1.5
mm apart at the smaller end to 4.5 mm at the larger. The septa are but
slightly concave, their depth being no more than 2 mm. The sutures run
nearly straight across the shell ; they show a very short, blunt lobe over the
siphuncle on the ventral surface, and a very faint, broad lobe over the dor-
sal surface. The siphuncle is situated close to the ventral side and is not
expanded between the septa.

The surface appears to have been smooth, the inner shell larger and,
as shown in one specimen, bearing some fine, longitudinal furrows.

The species has not been collected in the upper Guelph of Oak Orchard
creek, while in the lower bed both young and adult specimens were found,
the former exhibiting well the rather rapid expansion of the conch, and the
latter retaining part of the living chamber and a number of the youngest
camerae. In a large example the living chamber becomes greatly con-
tracted toward the aperture in about the same degree as a specimen

GUELPH FAUNA IN THE STATE OF NEW YORK 89

referred by Whiteaves ' with some doubt to this species. This contraction
may be here a gerontic character, as it has been claimed by Pompeckj and
Hyatt that numerous cephalopods constrict their apertures in gerontic

stages.

Cyrtoceras cf. brevicorne Hall

Plate 13, fig. iit 13

See Cyrtoceras brevicorne Hall, N. Y. State Cab. Nat. Hist. 2oth An. Rep't.
1867. p. 356, pi. 18, fig. 8, 9

A small, rapidly expanding cyrtoceracone from the Rochester collec-
tion, though quite incomplete, seems to agree with Cyrtoceras brevi-
corne Hall in the rapid expansion of the shell. In a length of 16 mm
it expands from 5 to 12 mm in diameter. The section is oval, broadly
rounded on the ventral and more acutely on the dorsal side. The inner
curvature is slight. Septa shallow, curving strongly downward on the
venter. The siphuncle is small and situated close to the ventral margin.
The chamber of habitation is not preserved in the specimen. The surface
is smooth or covered with fine concentric growth lines, which show a
broad and deep posterior curve on the venter.

The original specimens of this species were from the dolomite at
Racine Wis. The form has not yet been observed in either the Canadian
Guelph or the Niagara beds of New York, but is reported from several
outcrops of the Racine beds in Wisconsin.2

In the lower Guelph bed at Shelby has been found a short conch, which
in its extremely rapid expansion and curvature agrees with Hall's figured
specimen of Cyrtoceras brevicorne, but fails to show the difference
in convexity of the dorsal and ventral sides. Its section is, on the contrary,
perfectly circular.

1 Loc. fit. pi. 14, fig. 9.
"Geol. of Wisconsin, 2 : 376

90 NEW YORK STATE MUSEUM

Cyrtoceras bovinum sp. nov.

Plate 16, fig. 8, 9 ; plate 18, fig. 5, 6

Large, robust, rapidly tapering, gently and regularly curved cones. In
the most complete the arc of outer curvature is 165 mm long and its chord
135 mm, the inner curve 115 mm long, its chord 98 mm. Section trans-
versely oval, more rounded in the apical parts, but very broad and flattened
and even slightly depressed medially on the venter.

Septa closely arranged, from 2.5 to 4.5 mm apart; gently concave;
suture transverse with a low median backward turn or lobe on the venter.
Siphuncle subventran, moderately large, slightly contracted at the septa.
Living chamber long, not constricted as far as the specimens indicate.

Surface covered with only fine, concentric growth lines, which combine
to form low bands or festoons. All the internal casts of this species bear a
highly characteristic roughened surface, caused by the excoriation of the
inner shell layers indicating a thick shell. All surface lines make a broad
backward curve on the venter but are apparently transverse on the dorsum.
The shell is traversed longitudinally by very faint, fine and unequal, some-
what undulating lines and grooves. These, however, are shown only on
two fragments which seem to have somewhat less curvature than the others.

This species is represented by six or seven specimens from the Guelph
at Rochester, which show that it is by much the largest cephalopod in the
fauna at that locality. As a species it seems distinct from any that have
been described, in size, cross section and breadth of venter as well as in
surface characters.

OTBTOBHIZOOEBAS Hyatt. I QOO

Cyrtorhizoceras curvicameratum sp. nov.

Plate 17, fig. i-io

Diagnosis, Conch a cyrtoceracone of moderate size, gently arcuate,
curvature of apical part not known ; expanding slowly, adult living cham-
ber having a length of 35 mm, widening from a basal diameter of 37 mm
to an apertural diameter of 45 mm. Camerae very shallow, the sutures

GUELPH FAUNA IN THE STATE OF NEW YORK 91

being only 3.5 mm apart, where the major diameter of the conch is 43
mm ; deeply concave, the deepest place dorsad of the center, bent forward
strongly in the ventral and slightly in the dorsal region. Depth of septum
of living chamber 8 mm ; sutures transverse, with a higher, but narrow,
rather sharp ventral, and lower, broader dorsal saddle, straight on the
sides ; transverse section oval, compressed laterally, the venter narrower
than the dorsum, major and minor diameters in one narrow specimen 39
and 30 mm, in another broader, 44 and 36 respectively ; siphuncle small,
4.5 mm wide at the perforation of the septum, where the latter has a major
diameter of 44 mm, apparently empty, expanding to its double diameter in
the camerae, situated propioventran ; living chamber short, retaining the
curvature and expansion of the septate portion, aperture not constricted,
its lateral margins low, convex, the dorsal margin provided with a broad
and lower sinus and the ventral margin with a narrower and somewhat
deeper hyponomic sinus situated on the arched external side (exogastric
shell) ; surface not known, the internal casts being smooth and the molds
of the external surface obscured by coating of crystals. A coarse orna-
mentation was evidently absent.

Locality. Lower Shelby dolomite.

Observations. From Cyrtoceras cancellatum Hall, the only
form of the New York Niagaran showing some superficial similarity, C yrt.
curvicameratum is readily distinguished by being laterally com-
pressed and not dorsoventrally as the latter. In the rich cephalopod fauna
which has become known from the western Niagaran, there are Cyrt.
fosteri Hall and Cyrt. dardanus Hall, both clearly related to this
species. Cyrtoceras fosteri Hall, described1 from the "Niagara
limestone" near Chicago, possesses a similar transverse section, curvature
of sutures and like depth of chambers, but differs in having the venter
relatively narrower and the ventral saddle of the sutures higher. Cyr-
toceras dardanus Hall, occurring in the Racine beds at Waukesha
and Wauwatosa Wis., a form with similar curvature and expansion, is

1 Report of Progress of Geological Survey of Wisconsin for 1860, p. 41.

92 NEW YORK STATE MUSEUM

described1 as having the dorsal and ventral sides equally rounded, and it
also possesses deeper camerae.

This species, C. curvicameratum, is considered a typical repre-
sentative of the genus Cyrtorhizoceras Hyatt3 on account of its uncontracted
living chamber, open aperture and the character of its dorsal and hyponomic
sinuses, its laterally compressed form, the well developed ventral and dorsal
saddles of the sutures and the small siphuncle. The genus is described as
beginning in the Lower Siluric, where the generic type, Cyrtorhizo-
ceras minnesotense Clarke (sp.), a small form of the western Tren-
ton, occurs, and as extending into the Upper Siluric. It appears that this
genus, a very primitive group of cyrtoceracones, is still well represented in
the Niagaran, for several of the western species of Cyrtoceras evidently
pertain to it.

GYBOCERAS de Koninck. 1844

Gyroceras farcimen sp. nov.

Plate 18, fig. 1-4

Diagnosis. Conch robust, strongly curved, very slowly expanding,
number of volutions unknown ; transverse section circular, the dorsal and
ventral sides not appreciably different in curvature, no impressed zone
observable ; camerae moderately deep, septa 8 mm distant, where the diam-
eter of the shell is 28 mm ; sutures transverse, nearly straight, a small saddle
at the outer side of the arch ; siphuncle submarginal, at the outer side its
character not known ; living chamber very long, extending for one half a
volution or more, continuing with the curvature of the septate portion ;
aperture not known ; surface smooth.

Locality. Lower Shelby dolomite.

Observations. There are only three cephalopods with gyroceran volu-
tions known from the Niagaran; G. farcimen may be readily distin-
guished from G. abruptus Hall, of the Indiana Niagaran, by its very
gradual expansion and the position of its siphuncle, from G. americanum

1 Report of Progress of Geological Survey of Wisconsin for 1860. p. 43.
"Zittel-Eastman. Textbook of Paleontology. 1900. p. 529.

GUELPH FAUNA IN THE STATE OF NEW YORK 93'

Billings, by the fact that the latter is annulated and from G. bannisteri
Winchell & Marcy,1 from the western Niagaran, for the same reason.

POTKRIOCERAS McCoy. 1844

Poterioceras sauridens sp. nov.

Plate 14, fig. 1-19

The most common and one of the most characteristic cephalopods of
the lower bed at Shelby is a small breviconic cyrtoceracone, different in
important characters from all other forms reported from the Guelph or
so called Niagaran horizons. A single specimen somewhat crushed dorso-
ventrally was also obtained at Rochester.

Diagnosis. Shell small, fusiform, somewhat abruptly tapering and
relatively but little curved ; in a specimen with a length of 48 mm the outer
arc has a hight of 19 mm ; the inner of 4 mm, measured from a chord con-
necting the extremities. The shell is slightly asymmetric, and seen from
the ventral side, the apex is turned a little to the right. It is somewhat
compressed dorsoventrally, in its mature parts the dorsoveritral diameter
being one tenth shorter than the lateral ; the dorsum is almost flat or but
slightly rounded, while the ventral side is well rounded, its section in most
specimens being part of a circle. The ventrolateral slopes are evenly
rounded, while the dorsolateral are quite abrupt. In the apertural part the
section is entirely circular, the flattening of the dorsal side not appearing
till about the neanic stage of the shell. The living chamber is remarkably
short ; its length rarely attains that of the diameter of the last septum ; this
chamber is widest at about one third of its length, whence it contracts on the
ventral and lateral sides, toward the aperture to such a degree that the
dorsoventral diameter of the aperture becomes slightly the smaller. The
outline of the aperture is simple, with a shallow hyponomic sinus and a
broad, low dorsal saddle. The shell around the aperture is thickened, so
that on the very frequent casts of the living chamber, there appears a ring-
like depression just within the margin.

•According to Hall, N. Y. State Mus. 2oth An. Rep't, supplementary note, p. 393, this
is a Trochoceras.

94

NEW YORK STATE MUSEUM

Septa transverse, closely arranged, those of the ephebic stage being
about 3 mm apart on the ventral, 2 mm on the dorsal side ; shallow, with a
low saddle on the venter. Siphuncle ventral near the margin (propio-
ventran Hyatt), tubular in the nepionic part, becoming slightly nummuloidal
in the following stages. Surface with fine concentric lines which are recurved
on the venter, where they are crossed by obscure longitudinal ridges.

The species can not have attained a large size, for, among all the
specimens, none has been found to have a diameter of the living chamber
above 30 mm, this being the measurement of the largest specimen observed
which possesses distinct gerontic characters in the shallow later camerae.
Numerous specimens of average size with but two thirds of this measure-
ment, show the same gerontic features, and should therefore be regarded as
representing the normal size. An entire specimen whose living chamber
has a diameter of 18 mm, measures 54 mm along the ventral side.

Horizon and locality. Rare in the Guelph horizon at Rochester, but
very common in the lower Shelby dolomite ; one doubtful specimen has
been taken from the upper Shelby horizon.

Observations. The large representation of this species has allowed a
full elucidation of its characters ; and it is also possible to attempt a
generic reference more exact than to Cyrtoceras in its broad and common
application. The genus Cyrtoceras, as restricted by Hyatt, while including
similar exogastric, breviconic cyrtoceracones, with flat dorsum and elevate
venter, is defined as having the aperture contracted to a T-shaped opening,
and a large, nummuloidal siphuncle. Thus restricted, the generic term is
only applicable to Devonic forms, on which it was originally based, but we
have not been able to apply the term in this meaning because of lack of
evidence. Hence our use of the name in the foregoing is to be regarded
in a broad sense as covering species not at present referable with greater
exactitude. The genus Oncoceras, which is suggested by the short,
abruptly terminated septal part and the contracted aperture, is restricted
to laterally compressed forms of the Lower Siluric, with distinctly nummu-
loidal siphuncle. It is however clear that this genus is a primitive repre-

GUELPH FAUNA IN THE STATE OF NEW YORK 95

sentative of the genus Poterioceras, as defined by Hyatt, primitive in so far
as its aperture is not yet laterally contracted and still possesses a wide open,
roundly triangular outline ; also primitive in its less developed fusiform
shape, which, it appears, does not attain its most typical expression till Car-
bonic time. This genus, in its restricted sense, was placed by Hyatt
(Genera of the Fossil Cephalopoda),1 under the term Acleistoceras, but
subsequently was regarded by him as a synonym of Poterioceras ; Acleisto-
ceras nobis includes brevicone fusiform bodies with partially contracted
living chamber. The aperture has a large ventral sinus and a dorsal
saddle, and is only slightly smaller in diameter than the living chamber,
while the outline is usually subtriangular. The siphuncle remains ventral,
and the form in section is an oval with the dorsum broader than the venter.
It appears from the frequent coincidence of shallow ultimate camerae
indicating gerontic conditions, with marked contraction of the aperture,
that the latter feature alone may indicate gerontic condition rather than
specific character. This fact would, in some measure, conform to the state-
ment made by Hyatt, that Oncoceras is a phylogerontic group, one of the
phylogerontic characters being the transverse contraction of the living
chamber during gerontic age. On the other hand, it was pointed out by
Clarke that the expansion of the shell during later growth and a sudden
contraction at the close of the swelling near the aperture is a character
appearing in the early genera Oncoceras, Clinoceras, Poterioceras and
Cyrtoceras (in the old sense), and that in the Devonic species of the ortho-
ceran genus Bactrites this expression of the shell characterizes the growth
stage directly succeeding the formation of the protoconch. It is in line
with the latter observation that, as Foord remarks, the inflation of Poterio-
ceras is much less conspicuous in the adult than in the young. This author
probably refers only to late species of Carbonic age. It would seem to us
that we have here a gerontic character indicating early decline of a series
of cephalopods taking place remarkably soon after the inception of the
cephalopod stock. In considering the small size and slight development

•Boston Soc. Nat. Hist. Proc. 22: 277.

96 NEW YORK STATE MUSEUM

attained by the species of these genera, they appear to us as a group of
dwarfed forms comparable in their entirety to the small specimens with
constricted apertures among later (mesozoic) cephalopods considered as
dwarfs by Pompeckj.

One specimen, consisting of a badly crushed living chamber which may
belong to this species, was found in one of the geodes of the upper Guelph
at Shelby, and another was obtained at Rochester. The latter is probably
also somewhat crushed, for its section is very traverse, the dorsoventral
diameter of the body chamber being one third less than the transverse
diameter. This specimen measures 50 mm on the ventral curve and has an
apertural transverse diameter of 20 mm and an apical diameter of 8 mm.

It is a noteworthy fact that, with the exception of one or two
specimens, all have retained only the living chamber and a few camerae, the
apical parts being gone. It is therefore quite probable that this organism
was in the habit of discarding from time to time some of its oldest camerae.

There are no forms in the Guelph or Niagara similar enough to invite
comparison with this species or to necessitate distinctive characterization,
but Cyrtoceras clitus Billings' should be cited here as possessing
similar size, like curvature and contraction of the aperture, though still
differing in the amount of expansion, this being much more rapid in the
apical part of Pot. sauridens.

J. W. Spencer has described and figured2 the cast of a living chamber
as Cyrtoceras reversum. This cast resembles so closely that of the
same part of P. sauridens that it doubtless belongs to that species.
The author has succeeded however in making a very remarkable fossil out
of this fragment, viewing it in a wrong direction and then calling it
"reversum." He states : " Its form is rapidly tapering with a considerable
curvature, until it ends in a rounded point." This rounded point is, how-
ever, the aperture, and the tapering is that of the living chamber toward
the aperture. From this misconception arose the other, that "the convex

'Cat. Silurian Fossils of the Island of Anticosti. 1866. p. 85.
"Mus. Univ. Missouri. Bui. 1884. p. 60, pi. 7, fig. 8.

GUELPH FAUNA IN THE STATE OF NEW YORK 97

side of the septae is directed toward the body-chamber," a structure which
would indeed be quite unique among the Cephalopoda. Cyrtoceras
r eve rsu m is described as occurring in "the lower beds of the Niagara
limestones at lighthouse station on the G. T. R." It may, therefore, occur
at a similar horizon as the lower Shelby form.

Poterioceras sp.

Plate 13, fig. 13-16

A single living chamber, found in the lower Shelby dolomite, differs
so materially from those of the associated P. sauridens that we are
constrained to note it separately. The living chamber is quite evenly
rounded and plump, the flattening of the dorsal side but slightly devel-
oped. The section of the living chamber and also of the aperture is nearly
circular. The ventral and lateral surfaces are regularly and evenly con-
tracted from the middle of the chamber toward the aperture. The
siphuncle is marginal (subventral) and highly nummuloidal. The camerae
are not preserved, but, judging from the siphuncle, they were shallow and
the septa but slightly convex. The cast shows traces of transverse striae,
presumably growth lines.

PBOTOPHBAGMOCEBAS Hyatt. I QOO

Protophragmoceras patronus sp. nov.

Plate 19, fig. i, 2

A very robust, moderately tapering, strongly and regularly curved
shell. The arc of the outer curvature is 190 mm long and its chord is
165 mm ; the inner curve is about 140 mm long and its chord measures 90
mm. Section in the earlier part of the septate portion broadly elliptic,
the major axis being the dorsoventral ; the living chamber and mature part
of the cone have an oval or roundly triangular section, the outer (ventral)
side being very broadly rounded, the inner side narrowly so and the lateral
parts nearly flat, sloping to the dorsal ridge.

Camerae very deep, last septa being 21 mm apart on the ventral side
and about 8 mm on the dorsal side ; sutures transverse with a broad, low
saddle extending the full width of the venter. Depth of septum almost

98 NEW YORK STATE MUSEUM

half the depth of the camera ; siphuncle not retained ; living chamber rela-
tively very large, widening at the same rate as the septate portion ; aperture
not contracted, but open and simple. Surface unornamented, save by closely
and regularly disposed, faint growth lines, the course of which indicates the
presence of a shallow hyponomic sinus on the convex side of the cone.

Locality. Lower Shelby dolomite, Oak Orchard creek.

Observations. This large species has no equal in size among the curved
cephalopods of the Guelph of Canada or the Interior; it compares well in
this regard with the large forms to which Barrande applied the terms C.
tyrannus and C. rex. Cyrtoceras hercules Winch. & Marcy
( = C y r t. (Phragmoceras) amplicorne Hall) is a large form from
the Waukesha and Racine beds of Wisconsin, which possesses a stronger
curvature and broader venter. Cyrtoceras bovinum, a smaller, simi-
larly curved species from the Guelph at Rochester, expands more rapidly
and has shallower camerae. Phragmoceras nestor Hall, reported
as from the Niagaran at Wauwatosa Wis., is readily distinguished from
Protoph. patronus by the constriction of its aperture, its shorter liv-
ing chamber and shallower camerae ; from Phragmoceras byronen-
sis Worthen,1 described from the Niagaran of Port Byron 111., and which
very much resembles the Shelby species in the degree of its curvature and
rate of expansion, it differs in the same particulars.

The form of the shell, the degree of curvature and expansion, suggest
relationship to Phragmoceras, as was also indicated in Hall's description
of C. amplicorne by addition of that generic name in parenthesis.
Its open aperture and slightly developed dorsoventral expansion indicate
that it represents one of the primitive types of the Phragmoceratidae, for
which Hyatt has created the genera Cordoceras and Protophragmoceras.
On account of the general similarity of our form with the type of the latter
genus, Protoph. murchisoni Barr., which makes itself obvious in
the curvation, expansion, situation of hyponomic sinus and ventral position
of sutural saddle, we refer the species thereto.

'Geol. Sur. Illinois, 6:506.

GUELPH FAUNA IN THE STATE OF NEW YORK 99

PHBAGMOCERAS Sowerby
Phragmoceras parvum Hall & Whitfield

Plate n, fig. i-8

Phragmoceras parvum Hall & Whitfield, Paleontology of Ohio. 1875. 2:151,

pi. 8, fig. 10

Phragmoceras parvum Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i, p. 41,

pi. 7, fig. 2

Phragmoceras parvum Arey, Rochester Acad. Sci. Proc. 1892. 2:107

Phragmoceras parvum Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2, p. 105

Of the several species of Phragmoceras which have been described by
various authors from American Upper Siluric faunas one, P. parvum, is
notable for its small size and the projection of the dorsal horn of the aper-
ture. This species has been described only from internal casts of the
chamber of habitation. The original is from the dolomites at Cedarville,
Greene co. O., and others identified therewith are from the Guelph at
Hespeler. There are before us several fine small examples of Phragmo-
ceras from Rochester which retain in exceptional perfection the exterior
surface, the form of the apertural and septate portions, features which for
the most part have not been made known of P. parvum.

These shells in their entire condition are unguiform, sloping from a
stout chamber of habitation by a gentle curve to an acute apex, the septate
portion making about one half the length of the shell. The section of the
living chamber is broadly oval, but on the earlier parts the cone is more
flattened on the sides. The ventral margin is very broad, the dorsal
narrowly rounded and subangular. In expanding upward, the shell becomes
rather abruptly swollen at the base of the body chamber, thence, at first
gradually, then abruptly, contracting to the aperture, where two lateral
flanges of the shell almost meet in a median line, leaving a slitlike opening
between. The surface of this almost plane and vertically deflected area
slopes upward to the ventrolateral angle, where it is somewhat produced in
the form of a rather blunt tube. At the dorsolateral angle the tube is

IOO NEW YORK STATE MUSEUM

narrower and greatly produced. This latter feature is one of the distin-
guishing characters of the species.

The septa are slightly but regularly concave, the camerae quite shallow.
The siphuncle is ventral and almost marginal on the earlier septa ; its posi-
tion on later septa has not been observed. The surface, not heretofore
noted, is ornamented by quite regular, low, broad, concentric ridges sepa-
rated by narrow interspaces. These make a broad backward curve on the
venter, bend upward at the sides, and on the dorsum make a sharply angu-
lar, posterior curvature. At the aperture they are not parallel to or concen-
tric with the margins.

Dimensions. A specimen nearly entire to the apex has a length of
50 mm, the greatest diameter (living chamber, not including apertural
extensions) being 28 mm.

Locality. Upper Guelph horizon, Rochester.

TBOCHOCEBAS Barrande. 1847

(SPHYRADOCEKAS Hyatt)

Trochoceras desplainense McChesney

Plate 20, fig. 3-9

Trochoceras desplainensis McChesney, New Paleozoic Fossils. 1859.

p. 68, pi. 6, fig. r
Trochoceras desplainense Hall, N. Y. State Cab. zoth An. Rep't. 1867.

P- 359. P1- l6> % 8. 9, I0
Trochoceras desplainense Whiteaves, Paleozoic Fossils. 1884. v. 3, pt i,

P- 36, pi. 5, fig. 5
Trochoceras desplainense Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,

P- IOS

The specimens which we identify with this species are of better quality
than those which have heretofore been figured and studied, one of them
retaining almost in its entirety the living chamber and aperture, another of
somewhat smaller size preserving the umbilical aspect of the entire final
whorl to the aperture, while still other specimens illustrate the grosser and
finer characters of the early surface.

GUELPH FAUNA IN THE STATE OF NEW YORK IOI

This completeness of the material at hand gives basis for the amplifi-
cation of the characters of the species which have heretofore been drawn
solely from the immature conditions of the shell.

Shell dextral, forming a low torticone of about two and one half volu-
tions, not quite one half of the last volution being occupied by the living
chamber. The volutions expand and coil downward very gradually, so
that the apex of the shell and the upper side of the outer chamber lie in
almost the same horizontal plane. The section is described by McChes-
ney as being subelliptic with the dorsoventral diameter greater than the
lateral, while Hall states that the volutions in these immature examples
are " essentially circular." The Rochester specimens are subcircular in
the section of the early part of the last whorl but become laterally flat-
tened in later growth, so that in the final stages the cross section is ovate.
The ventral side is subacutely and the dorsal obtusely rounded, but the
latter is not flattened nor does it bear any trace of an impressed zone. In
gerontic specimens the sides become flattened to parallel planes, a fact
mentioned by Hall as characteristic of the genus. The siphuncle, which is
described and figured by Hall as being central, is centren in the nepionic
whorl, becomes however, in the mature stage, as shown by several of the
Oak Orchard creek specimens, ventrocentren. The ventral position of
the siphuncle is given by Hyatt as a family character of his Plectocera-
tidae, to which this genus appertains. The siphuncle is small, apparently
tubular. The camerae are of slight depth and the septa closely arranged
(the final ones 3 mm apart), the suture has a prominent saddle on the
venter and a broader and lower one on the dorsum. The lateral lobes are
shallow and broad, deepest near the dorsolateral curve.

The surface sculpture consists, in the earlier stages, of angular,
oblique ridges, with sliglicly concave to flat interspaces. These bend
strongly forward on the dorsal and backward on the ventral side, thus
intersecting the suture lines at a considerable angle. They become faint as
growth advances and on the last half or two thirds of the final whorl are
obsolescent, in old shells disappearing before septation ceases. Concentric

IO2 NEW YORK STATE MUSEUM

with these ridges and covering both ridges and the intervening sulci, are
finer lines which are crossed and cancelated on the early shell by revolving
lines of the same size. With the obsolescence of the ridges, the concentric
lines retained to the aperture become more and more conspicuous and
defined. The revolving lines may also be seen under favorable conditions
in later growth.

The living chamber continues in the curve of the volutions, though,
in a gerontic stage, it continues in a nearly direct line. The aperture is
large, provided with a shallow dorsal and probably a deep ventral sinus.

Localities. Not infrequent in the lower Shelby dolomite and at
Rochester ; rare in the upper Shelby bed.

This form was first described by McChesney from the " Niagara divi-
sion " of Joliet and on the Kankakee river, 111. Professor Hall obtained his
specimens from Racine Wis. and Whiteaves reports two specimens from
the Guelph at Hespeler. The shell is definitely dextral and is thereby
distinguished from the otherwise closely allied form termed T r o c h.
aeneas Hall1 from the dolomites at Lyons la.

The generic term Trochoceras was employed by Barrande in 1847 and
independently introduced by Hall in 1852. The former's conception of the
generic value is expressed in the species T. optatum Barr. (Etage E),
which is very closely allied to T. desplainense, but is a sinistral shell.
Hall's type is T. gebhardi Hall of the Coralline limestone, a shell with
high spire, smooth whorls and of quite distinct aspect from the group under
consideration ; it has been made by Hyatt the type of his genus Mitro-
ceras. Hyatt has taken Barrande's Troch. optatum as the type of his
genus Sphyradoceras, and we have therefore employed Trochoceras here in
the restricted sense ascribed to Sphyradoceras by its author.

Hyatt considers Sphyradoceras as an offshoot of Spyroceras, a genus
with, in early growth, longitudinally ridged, and, in later, annulated longi-
cones ; and mentions the presence of longitudinal ridges among the gene-
ric characters of Sphyradoceras. Our material does not show this last

ZN. Y. State Cab. of Nat. Hist. 2oth An. Rep't, revised ed. pi. 25, fig. 16.

GUELPH FAUNA IN THE STATE OF NEW YORK 1 03

named feature, but it appears that the fine longitudinal lines mentioned
above would point to the presence of longitudinal ridges in the neanic
stage, as they do in Spyroceras, in which Clarke1 has shown from Spyro-
ceras bilineatum, that coarser longitudinal ridges, with advancing
growth and by interplantation, become changed into more numerous
uniform, fine, longitudinal striae. The presence of such fine, longitudinal
striae in Troch. desplainense allows us, hence, to infer the presence
of longitudinal ridges on the earliest parts of the conch.

Trochoceras costatum Hall

Plate 20, fig, i, 2

Trochoceras costatum Hall, Geol. Sur. Wisconsin. Rep't Prog, for 1860-1861
Trochoceras costatum Hall, N. Y. State Cab. Nat. Hist. 2oth An. Rep't.

1868. p. 360
Trochoceras costatum Hall, N. Y. State Cab. Nat. Hist. 20th An. Rep't.

revised ed. 1870. p. 402, pi. 25, fig. 15

With the specimens of Trochoceras desplainense from the
lower dolomite at Shelby, are several which are not only sinistral, but also
differ from the former in their loose coiling and closer arrangement of
costae, sufficiently to warrant their reference to T. costatum, another
species reported from the Racine limestone.

Conch a low torticone, slightly asymmetric, but sufficiently to show
that it is sinistral, very closely coiled, with wide open umbilicus, expanding
moderately ; whorl beginning with circular section, becoming within the
first volution depressed convex and assuming an oval section ; position of
siphuncle not determined ; surface ornamented by strong annulations,
which cross the sides obliquely backward, in the earlier part of the whorl,
being slightly curved, with the convexity directed forward, and becoming
slightly sigmoidal on the later portion. On the venter they are curved
backward. The costae number nine within the first 10 mm of the whorl,
and the interspaces increase regularly till there are at the end of the
whorl five costae within 10 mm.

1 Geol. Minnesota, v, 3, pt 2, p. 786.

IO4 NEW YORK STATE MUSEUM

Observations. In describing this species, Professor Hall stated that it
differed from T. desplainense in its more numerous and more sharply
elevated annulations, which do not increase beyond the point opposite the
apparent apex of the shell. As " a conspicuously distinguishing feature,"
is cited the sinistral direction of the volutions. A comparison of the speci-
mens here described with our material of T. desplainense leaves no
doubt as to the greater prominence and closer arrangement of the costae
in that species, characters which give a distinctly different habit to the
shell. In regard to the sinistral enrolment, Hall deemed it necessary to
add an explanatory note, stating that, as inT. desplainense the inner
volutions are sometimes a little depressed below the outer, it might perhaps
be suspected that T. costatum is an exaggerated condition of the for-
mer species, with the inner volutions still more depressed. This, how-
ever, is claimed not to be the case, as T. costatum is clearly sinistral.
It is added that Barrande described several sinistral forms of Trochoceras
and found that "the enrolment is sometimes dextral and sometimes sinis-
tral according to the species, but the dextral forms greatly predominate."
In two forms, however, viz T. asperum and T. sandbergeri, Bar-
rande concedes that "we find both modes, varying in individuals." Bar-
rande's descriptions and fine figures of these two species, show that they are
but very slightly asymmetric. They belong therefore near the beginning
of the morphologic series, which according to Barrande, extends from
perfectly symmetric to the highly asymmetric torticones ; and it may be
inferred that the tendency to become asymmetrically enrolled to the right
side had not yet become established in these Bohemian forms. The two
sinistral species described by Hall, viz T. costatum and T. aeneas,
when compared with the decidedly dextral T. desplainense, are con-
spicuously less asymmetric, and therefore appear to represent an earlier and
less fixed stage. We are disposed to believe that the species of Trocho-
ceras can not be naturally divided into a sinistral and a dextral series, but
that, as by far the prevailing number of species and those the most pro-
gressed, are dextral and the sinistral are but slightly asymmetric, the gen-

GUELPH FAUNA IN THE STATE OF NEW YORK 1 05

eral tendency is toward a dextral enrolment, and the sinistral forms represent
only early variations. It should be noted also that the late Devonic species
are all dextral.

As Professor Hyatt has made no mention of this difference in enrol-
ment, it may be inferred that he did not regard it of special significance.
He did, however, at one time1 separate from Trochoceras in its restricted
sense the genera Peismoceras and Systrophoceras, basing these divisions
principally on the characters of the aperture, position of siph uncle and sec-
tion of whorl. From a note in Whiteaves's description of T. d e s p 1 a i n-
e n s e, it seems that Hyatt would have referred that species and evidently
also T. costatum to his Peismoceras. In Zittel-Eastman's Textbook of
Paleontology, however, he has covered these names again under Sphyrado-
ceras, which is here considered a synonym of Trochoceras Barrande, sensu
stricto.

Trochoceras costatum was described as from the Niagaran
limestone at Racine and near Milwaukee Wis. In v. 2, Geology of Wis-
consin it is only cited by Chamberlin among the species of the Racine
limestone, but not among the Guelph forms.

ANNELIDA

COBNUUTES Schlotheim
Cornulites arcuatus Conrad

Plate 4, fig. 1-5

Cornulites arcuatus Conrad, Acad. Nat. Sci. Jour. 1842. 8: 276, pi. 17, fig. 8

Three well preserved specimens from the dolomites at Rochester and
a greater number from both horizons near Shelby are referable to this
species which was described as follows :

Curved, rapidly attenuate ; the base of each ring contracted, the upper
edge angular.

It is not altogether certain that Cornulites flexuosus Hall
(== C. cl i n t o n i Hall) from the Clinton, is sufficiently different to permit

1 Phylogeny of an Acquired Characteristic,, p. 500 and 502.

IO6 NEW YORK STATE MUSEUM

the separation from this species though Professor Hall failed to identify
Conrad's species. Another specimen preserved as an internal cast has
the body longer and more slowly tapering than the rest, while the rings
project more at their lower ends ; this may represent a form approaching
C. flexuosus.

Most of these specimens are internal casts in part retaining the wall
of the tube.

No specimens of Cornulites are reported from the Guelph formation ;
Conrad's originals came from the Niagaran dolomite in the neighborhood
of Albion, Orleans co.

OSTBACODA

LEPERDITIA Rouault. 185!

Leperditia balthica Hisinger, var. guelphica Jones

Plate 21, fig. 9-1 1

Leperditia balthica Hisinger, var. gu elphica Jones, Contrib. Canadian
Paleontology. 1891. pt 3, p. 80, pi. 13, fig. iza, i2b, I3a-c

Leperditia balthica Hisinger, var. guelphica Whiteaves, Paleozoic Fossils.
l89S- v- 3. P* 2, P- i°6

Of quite common occurrence in the dolomites at Rochester are .speci-
mens of a large Leperditia agreeing in dimensions with the form which
Professor T. R. Jones has described under the name given above. These
are valves measuring, in the adult stage, from 10-12 mm in length, 5-6 mm
in hight, with long straight hinge, both angles of which are salient
and beyond which the curving margins of the valves extend for a slight
distance. The surface is smooth and quite convex, most so in front of the
middle ; the anterior slope abrupt, posterior gradual, the eye lobe well
defined. These features serve to distinguish it from L. phaseolus
Hisinger, var. guelphica Jones (Guelph of Ontario), which is more
oblique in outline, with angles not projecting and convexity more regular.

It seems quite possible that on close comparison L. balthica
guelphica may be found identical with L. fonticola Hall1 from

'N. Y. State Cab. Nat. Hist. 2oth An. Rep't. 1867. p. 335.

GUELPH FAUNA IN THE STATE OF NEW YORK IO7

Niagaran dolomites at Fond du Lac Wis., and it is evidently closely related
toL. scalaris Jones of the upper or Manlius waterlimes at Buffalo and
elsewhere in Western New York.

Leperditia sp. ?

Another large species of this genus is present in the Rochester fauna,
but the examples observed are insufficient for its determination. It has
narrower and more elliptic valves, rounded extremities and a curving hinge
line. It may eventually prove to be the L. phaseolus Hisinger, var.
g u e 1 p h i c a Jones.

A small Leperditia has been also noticed in the Lower Shelby dolomite.

TBILOBITA

CAI/TMMKNE Brongniart. 1822
Calymmene niagarensis Hall

Plate 31, fig. 12

Calymene niagarensis Hall, Geology of New York; Rep't on Fourth Dist.

1843. p. 182, fig. 3 (p. 101)
Calymene blumenbachii var. niagarensis Hall, Paleontology of New

York. 1852. 2:307, pi. 67, fig. ii, 12
Calymene blumenbachii Whiteaves, Paleozoic Fossils. 1895. v. 3, pt 2,

p. 107

The material of the Arey collection contains a few separated parts of
this species, all of the usual small size prevalent in the Rochester shales of
New York, the outcrops at Waldron and quite generally diffused in upper
Siluric strata. In the upper layers at Shelby all the specimens observed
attain much larger size than these.

Dr Whiteaves reports the species as occurring in the Guelph at Gait.
It is also reported by Whitfield from Cedarville O., but does not seem to
occur in the Guelph of Wisconsin.

IO8 NEW YORK STATE MUSEUM

Emmrich. 1845
Dalmanites sp.

A fragment consisting of some thoracic somites and part of the pygid-
ium insufficient however to determine the species was found at Rochester.
The surface of both parts is more coarsely granulose than in D. 1 i m u -
1 u r u s Green, and a row of coarse tubercles upon the segments indicates
relationship to D. verrucosus Hall. The segmentation of the pygidium
however is unlike either and the specimen may represent an unknown form.

PBOKTUS Steininger. 1830
Proetus sp.

Plate 21, fig. 13-16

At Rochester was obtained a single internal impression of a cranidium
of Proetus with tapering glabella, quite narrow and convex but not pro-
tuberant in front, eyes small and closely appressed to the glabella, anterior
border thickened and separated from the glabella by a narrow sulcus. This
form may prove to be the species referred to by Hall as Asaphus
stokesi Murchison1 but that is believed to have the anterior end of the
glabella more remote from the border as it is described as having " the
space between it [border] and the cheeks and glabella depressed in a broad,
shallow groove." Proetus corycaeus Conrad is of a somewhat differ-
ent type of glabellar structure.

The material from Shelby has afforded besides a glabella several small
pygidia of a Proetus with highly elevated strongly annulate axis and
deeply sloping pleurae with three or four obscure duplicating ribs. These
are also features ascribed to P. stokesi Hall.

The relatively frequent occurrence of the specimens of this genus in
the eastern Guelph is interesting in view of the fact that no species of
Proetus has been elsewhere reported from this fauna.

'Pal. N. Y. 1852. 2:316.

GUELPH FAUNA IN THE STATE OF NEW YORK

I09

SYNOPTIC LIST OF GUELPH FOSSILS OF NEW YORK

c — common, cc=> abundant, r=-rare, rr— very rare

>

>

HS

JH

««

§1

as

Eg

OTHER LOCALITIES

WQ

wo

£3

3°

$

i Zaphrentis cf. racinensis Whitf. -

rr

c

Racine beds of Wiscon-

sin,Guelph of Canada

2 Enterolasma cf. caliculus Hall (sp.)

-

.

c

Rochester shale, Lock-

port limestone, Ra-

cine limestone

3 Diplophyllum caespitosum Hall -

-

-

c

Anticosti group, Lock-

port limestone of

New York and Can-

ada, Niagara and

Guelph of Wisconsin

4 Heliophyllum sp. ind.

.

„

rr

5 Favosites niagarensis Hall -

.

cc

cc

Lockport limestone of

New York and Niag-

aran and Guelph of

Wisconsin

6 F. hisingeri E.&rff.

-

c

c

Niagaran and Guelph

of Ontario and West

7 F. gothlandicus Lam. -

-

-

rr

Anticosti group, Niaga-

ran and Guelph of

Canada, Niagaran of

New York, Michigan

and Wisconsin

8 F. forbesi E. 6- H. -

cc

c

c

Guelph of Canada ?

9 Cladopora multipora Hall -

cc

cc

-

Lockport limestone of

New York

10 Haly sites catenularius Linni -

-

c

cc

Niagaran and Guelph

of Canada and West

ii H. agglomeratus Hall -

-

r

r

Lockport limestone of

New York, Coral beds

of Wisconsin, Guelph

of Ontario (Nich.)

12 Syringopora infundibulum Whitf. -

-

c

-

Racine beds of Wiscon-

sin, Guelph of Onta-

rio

13 Stromatopora galtensis Dawson -
14 Clathrodictyum ostiolatum Nick. -

cc?

c
cc

c
cc

Guelph of Ontario
Guelph of Ontario

15 Crania ...

.

.

rr

16 Monomerella noveboracum sp. nov. -

cc

-

-

M o n. p r i s c a its clos-

est ally occurs in the

Guelph of Canada,

Ohio and Illinois

no

NEW YORK STATE MUSEUM

>•

•

3w

3s

X

i
«s

as

I!
w5

OTHER LOCALITIES

£g

gg

^o

o

g

OQ

1 7 Dalmanella cf. elegantula Dal. (sp.)

r

rr

Niagaran of New York

and Guelph of Onta-

rio and Wisconsin

18 D. cf. hybrida Sow. (sp.) -

-

.

rr

Niagaran of New York

and West, Racine of

Wisconsin

19 Leptaena rhomboidalis Wilckens, (sp.)

rr

-

-

Rare in Guelph of Wis-

consin

20 Camarotoechia ? neglecta Hall (sp.) -

-

c

c

Niagaran, Guelph of

Wisconsin

21 C. ? indianensis Hall

r

c

c

Niagaran of Indiana

and Kentucky

22 Spirifer crispus (His.) Hall var. -

-

c

c

Niagaran and Guelph

of Canada

23 Whitfieldella nitida Hall

-

cc

cc

Niagaran of New York,

Racine of Wisconsin

24 Rhynchotreta cuneata americana Hall

-

rr

-

Niagaran of New York

and West

25 Mytilarca eduliformis sp. nov.

-

.

r

26 M. acutirostrum Hall

r

-

-

Racine and Guelph of

Wisconsin

27 Pterinea subplana Hall

-

rr

rr

Rochester shale

28 P. undata Hall (sp.)

-

rr

-

Rochester shale

29 Conocardium sp. -

-

-

r

Conoc. sp. in Guelph

of Ontario

30 Cf. Modiolopsis subalata Hall

-

rr

.

Clinton and Rochester

shale

31 Bellerophon shelbiensis sp. nov. -

c

-

-

Niagaran and Canadian

Guelph

32 Trematonotus alpheus Hall -

cc

rr

rr

Racine of Wisconsin,

Chicago limestone,

Guelph of Canada

33 Diaphorostoma niagarense Hall (sp.)

-

rr

rr

Rochester shale,Guelph

of Wisconsin

34 Poleumita scamnata sp. nov.

.

c

cc

Canadian Guelph

35 P. sulcata Hall

.

r

r

Guelph of Newark,

Wayne co. N. Y., Ca-

nadian Guelph

36 P. crenulata Whiteaves (sp.)

c

-

c

Canadian Guelph

37 Trochonema cf. fatuum Hall -

-

rr

.

Guelph of Wisconsin

38 Eotomaria durhamensis Whiteaves (sp.)

.

.

rr

Canadian Guelph

39 E. areyi sp. nov. -

-

-

rr

40 E. kayseri sp. nov. -

-

-

rr

41 E. galtensis Billings (sp.)

rr

rr

-

Canadian Guelph

GUELPH FAUNA IN THE STATE OF NEW YORK

III

LOWER SHELBY
DOLOMITE

UPPER SHELBY
DOLOMITE

ROCHESTER
DOLOMITE

OTHER LOCALITIES

42 Lophospira bispiralis Hall (sp.)

C

.

r

Rare in Guelph of On-

tario

43 Hormotoma whiteavesi sp. nov.

-

r

cc

44 Coelidium macrospira Hall (sp.)

C

rr

c

Guelph of Ontario and

Wisconsin

45 C. cf. vitellia Bill, (sp.)

-

-

rr

Guelph of Ontario

46 Macrochilina sp. ind. - -

-

-

rr

47 Euomphalus fairchildi sp. nov.

-

-

rr

48 Orthoceras trusitum sp. nov.

c

rr

c

49 O. crebescens Hall

c

-

-

Waukesha, Racine and

Guelph beds of Wis-

consin

50 O. rectum Worthen -

rr

-

-

" Niagara limestone " of

Joliet 111.

51 Dawsonoceras annulatum var. ameri-

canum

c

-

r

Niagaran of New York,

Guelph of Ontario

52 Kionoceras darwini Bill, (sp.)

c

-

c

Racine and Guelph of

Wisconsin, Guelph of

Ontario, limestone of

Yellow Springs O.

53 K. cf. medullare Hall (sp.) -

rr

-

-

Waukesha and Racine

beds of Wisconsin,

Niagaran of Joliet 111.

Canadian Guelph

54 Cyrtoceras arcticameratum Hall

-

-

r

Guelph of Canada and

Wisconsin

55 C. erodes Bill.

r

-

r

Guelph of Canada

56 C. cf. bfevicorne Hall

rr?

-

rr

Racine beds of Wis-

consin

57 C. bovinum sp. nov.

-

-

c

58 Cyrtorhizoceras curvicameratumjr/. nov.

c

-

-

59 Trochoceras desplainense McChesney

c

rr

r

Niagaran of Joliet and

Kankakee river, Illi-

nois, Racine of Wis-

consin, Guelph of

Canada

60 T. costatum Hall

c

.

-

Racine of Wisconsin

61 Gyroceras farcimen sp. nov.

r

-

-

62 Poterioceras sauridens sp. nov.

cc

-

rr

63 Poterioceras sp.

rr

-

-

64 Protophragmoceras patronus sp. nov. -
65 Phragmoceras parvum Hall& Whitfield

rr

_

r

Guelph of Ohio and

Canada

112

NEW YORK STATE MUSEUM

>

SH

Jjjg

H

Kg

xs

Hi

M0

tnO

OTHER LOCALITIES

wo

E§

o3

pp

P.O

t)Q

o

OH

Q

9

H

66
67

Cornulites arcuatus Conrad
Leperditia balthica var. guelphica Jones

c

C

C
C

Lockport limestone
Canadian Guelph

68

Leperditia sp.

rr

.

r

69

Calymmene niagarensis Hall -

-

r

r

Niagaran of New York,

Guelph of Ontario

and Ohio

70

Dalmanites sp.

.

.

rr

Proetus sp.

-

r

rr

1

Summary

Total species recorded from the Guelph fauna of New York - - - - - 71

From Shelby - .... 52

From Rochester - .... - 52

Common to upper and lower Shelby horizons - 10

upper Shelby and Rochester - - 25

lower Shelby and Rochester 14

Shelby and Canadian Guelph - - 26

upper Shelby and Canadian Guelph - 15

lower Shelby and Canadian Guelph - 13

Rochester and Canadian Guelph - 27

New York and Canadian Guelph - 31

Shelby and Niagaran faunas of New York - - - 17

Rochester and Niagaran faunas of New York - - 16

New York Guelph and Niagaran faunas 19

Shelby Racine, and Waukesha limestones - 12

Rochester, Racine and Waukesha limestones 8

New York and Wisconsin Guelph - - 13

Species at Shelby not recorded from Rochester - 19

Rochester not recorded from Shelby - 18

In considering the relative prevalence of the various classes of organ-
isms in these manifestations of the Guelph fauna in New York we observe
that the several classes have the following distribution :

GUELPH FAUNA IN THE STATE OF NEW YORK 113

BRACHIO- LAMELLI- GASTRO- CEPHALO- CRUS-
CORALS PODS BRANCHS PODS PODS TACEANS

Lower Shelby 2+ 3 i 4 15 0

Upper Shelby - 962623

Rochester - 12 7 3 15 10 5

In the lower Shelby horizon the cephalopods prevail, notably in species
and profusely in individuals ; furthermore of the three brachiopods one is
Monomorella noveboracum which extraordinarily abounds and is
nowhere else seen ; of the four gastropods Trematonotus alpheus
is amazingly prolific and Poleumita crenulata is very common. As
to the corals we have every reason for believing that, originally abundant,
their skeletons have been largely destroyed by diagenesis.

In the upper Shelby-Rochester horizon, there has been less destruc-
tion of the corals, and the gastropods and cephalopods are prevailing
species though not rising to such individual development as in the
earlier appearance.

Comparing this condition with the relative development of these
classes in the typical Guelph fauna of Ontario as given by Dr Whiteaves
we find a corresponding prevalence of gastropods and cephalopods ; the
lamellibranchs are few in species (nine in a total fauna of 133 species) but
one of these is the ponderous Megalomus canadensis which is
extraordinarily abundant at definite horizons. The brachiopod species rise
to 24 but it is a noteworthy fact that throughout this fuller representation
of the Guelph fauna there is a larger percentage of normal or slightly
modified Niagaran forms than is present in the New York Guelph. No
crinoids or bryozoans are present in either case.

114 NEW YORK STATE MUSEUM

CONDITIONS OF LIFE AND SEDIMENTATION

DURING THE PREVALENCE OF THE GUELPH FAUNA
In surveying the composition of this fauna one is impressed with the
fact that irrespective of class divisions, the species on the whole are either
large and heavy shelled or diminutive and thin shelled. We may cite in
illustration of this the condition among the brachiopods. The Trimerel-
lidae including the genera Trimerella, Monomerella and Rhinobolus are
notable, not alone for their abundance but as well for their great size
and weight. Similarly heavy and abundant in Ontario is Pentamerus
occidental! s, but for the rest of the brachiopod species all are not
merely small and thin shelled but diminutive, specially those which have
been continued forward from earlier existence in the Niagaran fauna.
Among the lamellibranchs the Canadian fauna contains, as just noted,
the heavy Megalomus in surpassing abundance and another thick shelled
species, Goniophora crass a, but the other species in Canada
and all in New York are small and insignificant. The gastropods are
chiefly long, heavy, turreted shells, but a few are of small size. If a diverse
habit of growth is indicated by these differences we find that among the
cephalopods more uniform effects are expressed as though uniform condi-
tions encompassed and qualified this entire group. The well known habit of
life of these creatures would preclude the likelihood of their being subjected
to such widely distinct conditions as those which have affected the rest.
Of the trilobites all the large species of the Niagaran fauna are absent.

Professor T. C. Chamberlin, in studying the character of the upper
Siluric dolomites of Wisconsin, recognized the fact that the lenticular accu-
mulations of the Racine limestone were ancient coral reefs and we shall find
on comparison of the phenomena presented by the dolomites in New York
with these Racine reefs, with the Jurassic reefs which have been elaborately
investigated in France and with conditions of life and sedimentation pre-
vailing on existing reefs, conclusive reasons for construing those dolomites
as reef formations.

GUELPH FAUNA IN THE STATE OF NEW YORK

We may note, first, that the dolomite which carries the chert nodules
of the upper horizon (upper Shelby and Rochester) is highly magnesian.1

It shows no stratification, is usually dark and so bituminous that it gives
off a strong petroleum odor when fresh or struck with the hammer. It is
for the most part granular, though compact and contains numerous white
silicious concretions in which the fossils are preserved. Outside of these
nodules fossils are rarely found except remains of Stromatopora, Halysites
and other corals.

It is claimed by Walther and other writers and may be regarded a
matter of general acceptance that noncrystalline dolomites carrying so high
a percentage of magnesia as these are distinctly coraligenous.3 Coral rocks
of later geologic age may show higher percentages of magnesia than this as
the amount apparently increases the longer the process of diagenesis con-
tinues ; in other calcareous deposits the content of magnesia is always small
and this is in correspondence with the fact that shell limestones now form-
ing are low in magnesian content. The skeleton of living corals actually
contains but relatively little magnesian salts (M adrepora muricata
2.4$ and Isis 6.3$) but it is known that during diagenesis or the sum of the
little known processes by which a sediment is changed into rock,3 the coral

•One of the white chert nodules from the Nellis quarry, Rochester gave the following:

SiO 74-973$ Mg 4-366$

Ca 5-613$ CO. & HaO 9.112$

Fe & Al 68$ (Analysis by P. N. Coupland)

The dark dolomite from the same locality gave: MgO 20.95$ or MgCO3 44 ±$. The
lighter dolomite from the lower Shelby bed at Shelby gave: MgO 16.43$ or MgCO3 36 ±$.
(Analyses by G. I. Finlay)

"Walther. Einleitung in die Geologic als historische Wissenschaft. 1894. p.66^etsey.
3Doelter and Hoernes have supposed \Jahrb. k. k. geol.-Reichsanst. Vienna. 1875.
p. 331] that the magnesian salts of the sea water, specially Mg Cl, act on the calcareous
secretions of the organisms as soon as formed. Walther \op. cit. p. 708] thinks the pro-
duct due in large measure to bacterial action, just as bacteria have been shown to pro-
duce deposits of calcium carbonate by forming ammonium carbonate which in turn acts
on the calcium sulfate of the sea water.

Il6 NEW YORK STATE MUSEUM

rock segregates and concentrates the magnesia of the sea water more than
any other sedimentary material. We may note that the admixture of bitu-
minous matter in these Guelph dolomites is further indication of their coral
reef origin, or is at least in harmony with recent observations on living coral
reefs where petroleum has been found in process of formation as a result of
the transformation of the organic matter of the reef. The cavernous char-
acter of the dolomites may, according to the views of Walther and others,
be regarded not as the result of subsequent corrosion but as the remnants
of original cavities in the growing reef which have not been closed up with
coral sand.

The chert concretions which are characteristic of the upper Guelph
horizon at Rochester and Shelby are doubtless a byproduct of the diagene-
sis which altered the coral limerock to a dolomite. These nodules contain
fossils with their exterior ornament finely retained, that is replaced in amor-
phous silica, while in the dolomite the shell substance has been removed and
never replaced. The source of the silica here, as in the like segregations
associated with limestone, is probably to be found in spicules of sponges,
organisms which contribute importantly to the comminution of shells and
coral skeletons, specially the boring forms like Cliona.1 It is known that
sponges, both silicious and calcareous occur abundantly on the western edge
of the Florida bank.*

The suggestion, derived from its lithologic characters as to the reef
origin of the rocks, is fully borne out by the character of the fauna. The
dolomite everywhere contains fragments or traces of corals specially of
Stromatopora, Favosites, Syringopores and Cladopora. Here, however, as
in other cases of fossil coral reefs, the coral masses have been largely
destroyed or altered beyond recognition.

We have noted the existence of extremes of size in the Guelph organ-
isms, the ponderous heavy shelled species, and the diminutive forms. One
reading the account given by Klunzinger3 of the life inhabiting the reefs

'Hancock. Ann. and Mag. Nat. Hist. ser. 2. 3:231.
"Agassiz, A. Three Cruises of the Blake. 1888. 1:149.

aus Oberagypten. 1878. p. 334.

GUELPH FAUNA IN THE STATE OF NEW YORK I I J

of the Red sea learns that in the numerous cavities and in the small ponds
between the masses of seaweed there is displayed an overwhelming variety
of small gastropods, echinoderms, lamellibranchs and crustaceans. The
gastropods are evidently the prevailing class, the lamellibranchs fewer and
the cephalopods almost wholly absent. On the outer edge of the reef
where the surf beats with wild force and the corals best flourish there are
the thick shelled mollusks which without hiding defy the surf ; species of
Conus, Ricinula, Fasciolaria, Turbinella and Trochus. The ponderous
Monomerellas, Rhinoboli, Trimerellas, Pentamerus, Megalomus, Goni-
ophora crassa and the numerous large gastropods were obviously
adapted to similar life conditions on the Guelph reefs, and the contrasting
abundant small gastropods, brachiopods and lamellibranchs found congenial
conditions in the cavities between the branches of the coral stocks and in
the ponds among the alga patches on the reef.

More than one consideration suggests that increasing salinity assisted
the development of the thick shelled mollusks. We must look upon the
Guelph as a distinct phase in the development of the vast Niagaran coral
sea into the desiccating, inclosed sea of the Salina stage, when the salinity
of the water finally destroyed all life. The subsequent discussion of the
Guelph will show that the Guelph sea was the outcome of a shrinking of
the Niagaran sea; it is a derivative of the Niagaran fauna, specially of that
element which distinguishes the Racine dolomite of Wisconsin, but it has
greatly diminished and its residuum shows a definite adaptation to peculiar
conditions. It is therefore legitimate to conclude that the inclosure and
desiccation of the continental Niagaran sea had already begun to manifest
its influence. Investigations of recent marine faunas sufficiently support
this view. Von Baer has shown T that in the deep eastern channel of the
Caspian sea the magnesian carbonate is much increased and the calcium
salts are decreased over their relative proportions elsewhere ; under this
altered composition of the sea water the shells grow thick and heavier,

1 Neues Jahrb. fur Mineral. 1856. p. 591.

Il8 NEW YORK STATE MUSEUM

while in the less saline waters of the shallow region they are thin and
small.

The dolomite series from the top of the Rochester shale into the
Salina bed shows an irregularly increasing magnesian content and increas-
ing salinity. The occurrence of immense banks containing millions of the
extraordinarily ponderous Megalomus suggests that increasing salinity may
be an essential cause of its great size, for oysters are known to similarly
increase in size and thickness of shell in the deeper and more saline parts
of the sea. The corals, however, are considerably more sensitive to lack
of salt than to increase in salinity. They avoid the neighborhood of river
mouths but flourish luxuriantly in the Red sea, which receiving little fresh
water drainage, and having but restricted communication with the open sea,
is known to possess considerably higher salinity than the ocean without.
Altogether the Red sea with its greater salinity, extensive coral reefs and
abundant life seems an excellent portrayal of the conditions of the Guelph
sea. A complete inclosure of that body of water would repeat the condi-
tions that led to the formation of the Salina beds, with the exception that
the Salina sea still at times received much terrigenous detritus.

Various writers have shown that once the optimum of salinity is passed
concentration of the brine produces disastrous effects on organisms. Dall
has shown that in the salt lagoons or salt pans of the Bahamas ' the effect
of this concentration is shown in the diminished size and thin shells of the
mollusks and among the gastropods in a tendency to irregularity of coil
and effacement of sculpture. Such extreme conditions may be conceived
to have led to the depauperation and actual extinction of the fauna of the
Salina stage. In this connection we may note one gastropod of the Guelph,
Loxoplocus solutus Whiteaves, which is unique among upper Siluric
gastropods in being a completely uncoiled Murchisonia, and which may
have received the impulse to its peculiar aberration from the gradually
increasing salinity of the water.

*Mus. Comp. Zool. Bui. 1894. v. 25, no. 9, p. 113.

GUELPH FAUNA IN THE STATE OF NEW YORK Ilg

We may compare the conditions of the Guelph sea and the character of
its fauna with those of fossil coral reefs which have been clearly recognized
in the sediments of other formations. Perhaps the best instances are to be
found in the Jurassic reefs of France and the Racine reefs of Wisconsin.

In France the investigations of Oppel, Niosch, and more specially of
the Abbe Bourgeat,1 whose results are reproduced in condensed form in
Felix Bernard's Principles of Paleontology? have shown that reefs were
formed at various epochs of the upper Jurassic, and that for every sep-
arate coral facies there is always a corresponding muddy or lagoon facies
and pelagic facies of the same age, but very different in the character of the
fossils. The reef of Valfin is cited in illustration of these conditions.
The mass of the reef is described as a limestone of corallic origin ; here
and there in the irregular mazes is found the special fauna of the reefs
which is here very abundant, and particularly rich in forms showing a thick
test " which is in accordance with the fact that, the corals growing in
regions beaten by waves, the forms, inhabiting them, must necessarily be
provided with a strong power of resistance, while small sized species having
a thinner covering are only found in well sheltered places." The fauna is
described as follows : " There are of the gastropods numerous Nerineas,
Cerithiums, Naticas, Turbos, Pleurotomarias ; of the Acephala, Diceras (13
species), Lima, Pecten, Trigonia, Corbis ; regular Echini of the v family of
Cidaridae." We note that the Pleurotomarias, which appear in the Guelph
reef with 14 species, are still prominent upon the Jurassic reefs, the long,
turreted, heavy Paleozoic Murchisonias, Loxonemas, Subulites correspond
in their habit to the Nerineas and Cerithiums so prominent upon the
Jurassic reefs; and the Poleumitas, so abundant in our Guelph are the
Turbos of the later reefs. The Acephala however had not yet attained
prominence among the earlier reefs.

On the east side of the Valfin reefs the coraligenous facies changes,
passing by intercalation into marls more and more mixed with clay. This

'Recherches sur les formations coralligenes du Jura meridional. 1887.
a See translation in N. Y. State Geol. i4th An. Kept. 1895. p. 200.

I2O NEW YORK STATE MUSEUM

is the lagoon region between the barrier reef and the shore " which was not
far to the east." Its fauna is greatly different from that of the reef, the
heavy Nerineas and Diceras and the corals having entirely disappeared.

On the other side of the reef the corals disappear suddenly and the
pelagic facies extends far toward the north into the open sea. It is charac-
terized by Ammonites, Belemnites, brachiopods and Echini.

The great numeric preponderance of the cephalopods in the lower
Shelby dolomite would, by comparison with the equal preponderance of this
class in the pelagic facies of the reef, suggest that this may represent the
pelagic facies or pelagic side of an early Guelph reef.

An excellent description of the facies of the ancient coraliferous sea
of Racine age in Wisconsin has been given by T. C. Chamberlin.1 We
quote part of his interesting summation :

It appears, then, that in the southern counties there are three well
marked classes of limestones, with intermediate gradations, one class, con-
sisting of very irregular often brecciated or conglomeritic dolomite, forming
masses that usually appear as mounds, or ridges of rock, of obscure stratifi-
cation, a second class, formed of pure, soft, granular dolomites, a part of
them calcareous sandrock, and a third class, consisting of compact, fine
grained, regular, even beds. We have demonstrated that the three forms
change into each other when traced horizontally. - They were therefore
formed simultaneously. The view that best explains these facts is, (i) that
the mounds and ridges were ancient reefs, and (2) that the granular sand
rock was formed from calcareous sands, derived by wave-action from the reef,
and (3) that the compact strata originated from the deposit of the finer cal-
careous mud that settled in deeper and more quiet waters, the whole process
being analogous to, if not identical with, the coral formation of the present
seas.

But before pursuing this analogy farther, it will be well to consider the
evidences of life found in these rocks. While some of the reefs, or at least
that portion of them that happens to be exposed to examination, present
only a few fragments of fossils, others are prolific in organic remains, and
some of them are remarkable for the richness and variety of their fauna.
The reef near Wauwatosa (Schoonmaker's quarry), is a striking instance of
this. There have been collected from it, chiefly by Dr Day, probably not
less than 200 species. Of these there have been identified 28 corals, 8 bryo-

1 Geol. Wisconsin. 1877. 2:368-71.

GUELPH FAUNA IN THE STATE OF NEW YORK I 2 1

zoans, 4 crinoids, 19 brachiopods, 1 1 gastropods, 9 lamellibranchs, 24 cephalo-
pods, and 16 trilobites. And an exhaustive examination of the collections
would doubtless much increase the number.

Of the granular varieties of rock, that which is nearest allied to the reef
rock is peculiarly notable for an abundance of crinoids. The locality near
Racine is preeminent in this respect. Upwards of 30 species have been
identified from this one locality. These are associated, as will be seen by
consulting the table, with a large number of corals, brachiopods, gastropods,
cephalopods, trilobites and a lesser number of other forms.

The fauna of the compact strata is distinguished for the conspicuous
presence of the straight and curved cephalopods with comparatively few
associates. The cephalopods are abundant, as already noted, in the reefs
and crinoid beds, but are overshadowed by the number and variety of other
forms, while in the compact rock they greatly predominate.

It appears then, (i) that upon the reefs there swarmed a vast variety
of life ; (2) that upon certain banks or shoal areas there was also great
abundance and variety, among which the crinoid family attained unusual
prominence ; (3) that over areas of submarine sand flats there either was
little life present, or, from the porous nature of the rock, it has been illy
preserved, and (4) that over the deeper areas, that deposited fine calcareous
mud, the gigantic cephalopods held sway. The counterpart of all this is to
be found among the coral reefs of today.

These conditions in Wisconsin continued from Racine into the Guelph
time, as Chamberlin says of the Guelph (p. 377) :

In its lithological character, in does not differ essentially from the
Racine limestone, being in general a rough, thick bedded, irregular dolo-
mite, usually quite free from impurities, and of buff, gray, or blue color.
The distinction between the two subdivisions is a paleontological rather
than a physical one. In the latter respect there is less difference between
these than either of the other members of the group. There was evidently
no marked change in the physical history of the region, but the same con-
ditions continued from the beginning of the deposit of the Racine limestone
to the close of the formation of the Guelph beds. In the interval, however,
the life underwent a change by the introduction of the species that charac-
terize the Guelph horizon. This introduction was gradual, so that many
localities show a mingling of the two faunas.

In New York the Guelph period was still a time of coral reefs, and the
distribution of the peculiar fauna, characteristic of this reef in Ontario and
Ohio, shows that probably the entire shallow Guelph basin was more or less
studded with coral reefs.

122 NEW YORK STATE MUSEUM

DISTRIBUTION OF THE GUELPH

In the identification of the Guelph fauna in North America difficulties
arise from two sources, firstly from the evident failure to discern
between the Niagara and Guelph rock in some regions, again from the lack
of reliable fossil lists of the upper Siluric. On account of the changing
correlations of the upper Siluric beds in some of the states with advancing
knowledge such an inquiry has to assume the character of a history of
investigations upon the Guelph in these states. We, therefore, present
here such a history which will furnish the data for a summary statement
of the distribution of the Guelph in North America.

After Professor Hall had recorded the existence of "Onondaga salt
group" fossils in Wayne county, N. Y. and in Ontario, he discovered dur-
ing his geologic investigations of Iowa1 a limestone at the Rapids of
Le Claire, Iowa of which he says :

"In descending the Mississippi river the Niagara limestone is suc-
ceeded by a gray or whitish gray limestone. The whole mass is semi-
crystalline, very porous, and vescicular from the solution and removal of
fossils." He thought that it might exceed 600 feet in thickness and adds :

So far as we are able to ascertain this important formation has not
heretofore been recognized in western geology, or, if recognized, has been
confounded with the Niagara limestone. From this, however, it is quite
distinct, both in its lithological character and its fossil remains.

The fossils are all in the form of casts, and among them is a small
Spirifer, a Spirigera, a Pentamerus undistinguishable from P. occiden-
tal is, several gastropods and some chambered shells. In this reconnais-
sance no very complete collections were made, but as far as they enable us
to form an opinion, the fossils of the limestones of the Le Claire rapids are
very similar to those of the limestone of Gait in Upper Canada. The simi-
larity of position is worthy of notice.

Should the identity of the limestone of these two distinct localities be
proved, it will afford sufficient ground for separating these beds from the
Onondaga salt group, and for establishing a distinct group. It seems quite
probable that the limestones of this period have their eastern extremity in
central New York, where, from their small development, as well as from

1 Geol. Sur. Iowa. 1858. 1:73-80.

GUELPH FAUNA IN THE STATE OF NEW YORK 123

similarity of lithological character there seemed no sufficient ground for
separating them from the nonfossiliferous bed of the Onondaga salt
group. Since, however, in Canada these beds attain considerable impor-
tance, and (admitting the conclusions above given) acquire a still greater
thickness and more distinctive character on the Mississippi river, it seems
necessary to elevate these to the same rank as the other groups of the
series.

Hall here first clearly recognizes the Gait beds as a separate group and
this position was strongly reiterated in Paleontology of New York, 1859,

3:30.

This correlation of the Le Claire limestone was soon after attacked by
A. H. Worthen1 who claimed that the limestone was without any true
lines of bedding, that Hall greatly overestimated its thickness3 and that the
beds and fossils at Le Claire were to be correlated with those of Bridgeport
near Chicago and Port Byron 111., "all of which are claimed to represent
but the Niagara limestone." It would appear, however from Worthen's
statements that the fossils upon which he bases his views, specially Penta-
merus oblongus, occur only in the lower part of the bed at Bridge-
port and Port Byron, while Hall already cited a distinct Guelph form in
Pentamerus occidentalis from the Le Claire limestone. Hall and
Clarke have cited several species of Trimerella and Monomerella from Port
Byron and other localities of this dolomite and there can be no doubt that
the Guelph is represented therein.

This rock is described by Worthen 3 as follows :

At Bridgeport, near Chicago, the rock presents the same general char-
acters as at Port Byron and Le Claire, and is extensively used for the manu-
facture of lime. West and northwest of Chicago and just outside the city
limits, it is highly charged with petroleum. . . This bituminous portion of
the limestone is from 35 to 40 feet thick, and at the artesian well was found
to be underlaid by about 80 feet of regularly bedded limestone, which no
doubt includes the Athens marble and the Joliet limestone.

'Am. Jour. Science. 1862. 33: 46-47; Geol. Sur. Illinois. 1866. 1:30.
"The latter point was conceded by Hall in the N. Y. State Cab. Nat. Hist, zoth An.
Rep't. 1867. p. 307.

s Geol. Sur. Illinois. 1866. i: 132.

124 NEW YORK STATE MUSEUM

From these statements of Hall and Worthen it would appear that the
uppermost 35 to 40 feet of these beds alone may represent the Guelph.

A few years later Hall explored the geology of the central and eastern
portions of Wisconsin, and the adjacent parts of Illinois. His results are
published in the Report of the Geological Survey of Wisconsin, 1862, v. i.
In this important work he separated [p. 67] the Racine limestone from the
Niagara limestone proper, as the upper member of the Niagara group. Of
the fauna of this limestone is said :

Few of the species are identical with those in the Niagara group farther
to the east, or in the State of New York, though the Caryocrinus, in its
condition of casts, is not distinguishable from the C. ornatus of New
York, Kentucky and Tennessee.

The species already identified with known species of the Niagara group
in New York in addition to the Caryocrinus, are Spirifer niagaren-
sis, S. radiatus and Strophomena rugosa, while we have a Spiri-
fer allied toS. sulcatus and an Illaenus closely allied to or identical
with L. (Bumastus) barriensis.

In regard to its correlation it is stated : " It may be considered iden-
tical with the Le Claire limestone of Iowa, holding precisely the same
geological position, and containing some similar if not identical fossils, and
both limestones must be regarded as a part of the Niagara group."

From this statement it is clear that, on account of the recognition of
New York Niagaran fossils in this Racine bed, Hall considered the Le Claire
limestone, which he here correlates with the Racine, neither as belonging to
the Onondaga salt group nor to a later stage than Niagaran, but as a mem-
ber of the Niagaran group.

No mention was made in this report of the finding of Guelph fossils
in the Racine bed, but it is stated in the soth Annual Report of the New
York State Cabinet Natural History, 1867, p. 307:

At the same time, we have recognized from Racine and adjacent locali-
ties, including Le Claire in Iowa and a single locality in Illinois, the following
species which are identical or very closely allied to those from Gait in
Canada West: Pentamerus occidentalis, an Obolus-like fossil, a
Favosites and a species of Amplexus which are identical in several locali-
ties, Cyclonema sulcata, Murchisonia logani, Murchisonia iden-

GUELPH FAUNA IN THE STATE OF NEW YORK 125

tical or closely allied to M. mylitta Billings, an undescribed Murchisonia
identical with one from Gait, Subulites ventricosa, Pleuroto-
maria solarioides?, Loxonema longispira, besides other forms
which are closely allied to species of the Guelph limestone.

Hall had hence clearly recognized the presence of the Niagaran and
of the Guelph fauna also in the Racine beds, a conclusion which has been
fully verified.

While Hall worked out the relations of these beds in the west, Billings1
added to the Guelph fossils described by Hall in v. 2, Paleontology of
New York, a considerable number of new forms, among them specially
the large brachiopods Trimerella and Monomerella cited hitherto as
Oboluslike forms, and Logan 2 described the stratigraphic relations of the
formation in Canada. As to the relation of the Niagaran and Guelph
Sir William remarks in this work :

In Canada, the Niagara rocks are succeeded by a series of strata,
which appear to be wanting in the State of New York. . . It has
already been stated that the strata seen near the mouth of the Riviere aux
Sables, at Chief's Point, probably strike along the coast, by Lyell Island to
Cape Hurd ; and belong in part to the Niagara formation whose character-
istic fossils are met with in several localities along the shore. These strata,
however, have for the most part the lithologic characters of the Guelph
formation, and some of their undescribed species of Murchisonia have a
strong resemblance to others found in this series. The Pleurotomaria
huronensis, which belongs to the Guelph rocks, occurs on Lyell island
associated with Pentamerus oblongus, and other characteristic
Niagara species ; so that it is not impossible that some of the strata along
this coast may constitute a passage between the Niagara and Guelph
formation.

The Guelph formation appears to be absent from the State of New
York, and in Canada it probably has the form of a great lenticular mass,
the limit of which between Niagara and Guelph is uncertain, though it
appears to extend beyond Ancaster. In the other direction it seems to thin
out in Lake Huron, before reaching the northern Peninsula of Michigan.

Hall had noted before this3 that "at some points on the northern shore
of Lake Michigan and elsewhere in the lake region, there occurs a light

1 Paleozoic Fossils. 1861-65. v- *•
1 Geol. Canada. 1867. p. 336.
s Pal. N. Y. 1859. 3:30.

126 NEW YORK STATE MUSEUM

colored limestone lying above the Niagara strata, containing generally few
fossils and among them some forms not unlike those of that in Canada
West."

As to the general character of the Guelph Hall concludes : '

I am therefore induced to believe that this limestone at Racine, the
mass at Le Claire and extending thence into Iowa, as well as the Guelph for-
mation in Canada and the feeble representation of the same in New York,
are really lenticular masses of greater or less extent, which have accumu-
lated upon the unequal surface of the ocean bed in a shallow sea during the
latter part of the Niagara period. These isolated masses of limestone have
close relation with each other while their relation with the Onondaga salt
group, though very intimate in the single locality in central New York,
becomes less and less conspicuous in a westerly direction.

A considerable number of Gait fossils are described in this aoth
Museum report among the fossils from the Racine beds of Wisconsin.

Wisconsin. The relations of the Guelph of Wisconsin have been fully
treated by T. C. Chamberlin in Geology of Wisconsin, 1877, 2:335 ^ Se9'
The Niagara group is here divided as follows from top downward :

At the south At the north

1 Guelph beds i Guelph beds

2 Racine beds 2 Racine beds

c 3 Upper Coral beds

3 Waukesha beds \ 4 Lower Coral beds

[ 5 Byron beds

4 Mayville beds 6 Mayville beds
In regard to the Guelph and Racine beds it is said :

The term Guelph has been applied to the uppermost beds on account
of a similarity of fossils to those of the Guelph limestone of Canada, to
which the Wisconsin formation is probably equivalent. The recognition of
this equivalence is due to Professor Whitfield.

The Racine beds are the equivalent of what has been known as the
Racine limestone, except that the upper portion is now separated as Guelph,
and the reefs and associated rocks west of Milwaukee which have been
referred to a lower horizon, are included in it.

The suggestion of Hall that a Guelph and a Niagaran horizon are con-
1 N. Y. State Cab. Nat. Hist. 2Oth An. Rep't. 1867. p. 307.

GUELPH FAUNA IN THE STATE OF NEW YORK 127

tained in the Racine limestone, has here been verified and the separation
carried out.

The fauna of the Racine limestone was described and figured by R. P.
Whitfield in Geology of Wisconsin, 1882, v. 4. A consideration of the
fossil lists there given brings out some interesting facts.

In the Lower Coral beds there occur, together with Niagaran corals,
Dinobolus conradi (originally described from the Le Claire and
Racine limestones), Trimerella grandis, Trochonema (Poleumita ? ),
Murchisonia hercyna (a Canadian Guelph form called billings-
ana by Miller, as Billings's name is preoccupied). This limestone is 70
feet in greatest thickness.

None of these fossils occur in the Upper Coral beds (90 feet).

The Racine beds (consisting of three facies, viz coral reefs, coral sand
and compact strata with cephalopods) contain, together with typical Niaga-
ran brachiopods, the following Guelph forms :

Trimerella grandis, Whitfieldella hyale, Megalomus
canadensis, Straparollus solarioides, Bucania angus-
t a t a (— T rematonotus alpheus), Murchisonia macros-
pira, M. mylitta, C y rto ceras b r e vi co r ne, C. arc t i camera-
turn, Trochoceras desplainense.

The Guelph bed is said not to differ essentially from the Racine, being
in general a rough, thick bedded, irregular dolomite, usually quite free from
impurities. The distinction between the two subdivisions is paleontologic
rather than physical and the introduction of the Guelph fossils was so
gradual that many localities show a mingling of the two faunas. The beds
are more regular and compact than the subjacent Racine and gastropods
predominate among the fossils.

The following Canadian Guelph species appear in the list of fossils :

Monomerella prise a, Whitfieldella hyale, Megalo-
mus canadensis, Holopea guelphensis, H. harmonia,
Loxonema boydi, M. hercyna, M. logani, M. longis-
pira, M. macrospira, Cyrtoceras arcticameratum.

128 NEW YORK STATE MUSEUM

These lists bring out the following facts: (i) that a considerable num-
ber of characteristic Guelph fossils appear as early as the Racine beds, a
few even in the Lower Coral beds, (2) that the large brachiopods
(Trimerellids) appear before or with the earliest Guelph gastropods (as at
Shelby), (3) that neither the Racine nor the Guelph beds of Wisconsin
contain a pure Guelph fauna, but also numerous Niagaran forms.

Hall and Clarke,1 writing at a later date than the work cited, give the
following brachiopods from Wisconsin :

Rhinobolus davidsoni H. & C., Grafton, Monomerella cf.
orbicularis Billings, near Grafton, M. egani H. & C., Grafton, M.
greeni H. & C., Grafton, Dinobolus conradi Hall, Racine, Graf-
ton. Schuchert cites ' also Conchidium occidentale Hall, Williams-
town, Stricklandinia multilirata Whitfield, Sheboygan.

Iowa. Dr Samuel Calvin in the Report of the Geological Survey of
Iowa, 1896, 5:50, has divided the Niagaran into four stages from the top
down : Bertram, Anamosa, Le Claire, Delaware (Hall's Niagara).

In regard to the Le Claire stage it is stated that its strata are restricted
to the southwestern corner of the Niagaran area. It is generally a massive
or heavy bedded, highly crystalline dolomite. It contains little chert and
in its lower part there are few fossils. There are occasionally specimens of
Pentamerus of the P. occidentalis type, and casts of corals. In the
upper part small brachiopods abound of the genera Homoeospira, Tremato-
spira, Nucleospira, Rhynchonella, Rhynchotreta, Atrypa, Spirifer and prob-
ably others.

The Le Claire limestone is, in some respects, unique among the geologic
formations of Iowa. Locally, it varies extremely in thickness, so that its
upper surface is very undulating and it is strongly cross bedded. It is
suggested by Calvin that the eddies of strong currents piled up the material
in lenticular heaps.

Anamosa stage. This is Hall's " Onondaga salt group ", an earthy,

'Pal. N. Y. 1892. v. 8, pt i.

"Synopsis Am. Paleoz. Brach. 1897. p. 187.

GUELPH FAUNA IN THE STATE OF NEW YORK 129

finely and perfectly laminated dolomite, quite free from fossils, but in Cedar
county the brachiopod fauna of the upper part of the Le Claire reappears in
great force, up near the top of the formation. It was laid down on the
uneven floor of the Le Claire formation.

Bertram stage. An irregularly bedded, nonfossiliferous dolomite with-
out fossils.

In volume 1 1 of the same report, the Anamosa and Le Claire stages are
grouped together under the "designation Gower limestone.1 The Anamosa
" phase " is said to consist of soft granular limestones (dolomites ? ) with
very few fossils, while the Le Claire facies is hard bluish gray limestone
(dolomite?) with numerous fossils. "These are often gregarious, and
while no complete list of species has been made out, the fauna is known to
represent that of the Guelph of Canada. The Le Claire occurs in places in
mounds 50 feet high and over, in which little semblance of stratification is
to be seen. The rock is brecciated or conglomeritic." [p. 305]

This paper accepts the theory which had already been suggested by
Hall that "at the close of the Niagara huge mounds and ridges were built
on the bottom of the shallow Silurian sea, in part by the accumulation in
situ of corals, crinoids and molluscous shells, and in part by the drift of cal-
careous sediments under strong currents. That these reefs were near the
surface is attested by their conglomeritic character."

Illinois. The reports of the Illinois Geological Survey [1-8] give no
data in regard to the occurrence of the Guelph in Illinois, as Worthen
declined to admit the Guelph nature of the Le Claire limestone [see above].

We have cited above, a number of typical Guelph species from Illinois
localities but we learn from Prof. Stuart Weller who has been intimately
concerned with the study of the Niagaran fauna that it is not now possible,
with existing exposures, to say what part of the species recorded as from
the "Niagara" of Illinois have actually been derived from the upper or
Guelph horizon.

There are at Grafton 120 feet of a buff colored dolomite in regular

1 Norton, W. H. Geology of Cedar County.

130 NEW YORK STATE MUSEUM

beds and in Cook county the upper beds are described as consisting of a
light gray fossiliferous limestone weathering to a yellow or buff color, of a
decidedly concretionary structure, and showing stratification very imper-
fectly. The rock is in many places stained with bitumen, and contains cavi-
ties filled with the substance in a semifluid condition. This rock seems to
agree lithologically with the Guelph beds of Wisconsin.

Indiana. No indications of the presence of the Guelph beds in this
state have been found in the Indiana geological reports. In the 2ist
report the following series of beds is given by Foerste : (i) Clinton; (2)
Basal Niagara limestone ; (3) Lower Osgood clay; (4) Osgood limestone;
(5) Upper Osgood clay ; (6) Laurel limestone ; (7) Waldron shale. Above
the Waldron shale follows the Louisville limestone, with an average thick-
ness of 40-55 feet. In regard to this it is stated [p. 233] that immediately
below the overlying Corniferous limestone there are found in it, in Clark
county, Pentamerus mysius van crassicosta, Strombodes
pentagonus, Favosites favosus, Halysitescatenulatus.
There is herein no Guelph representation in the Louisville limestone.
In the 22d annual report, Foerste [p. 214] records that fossils are rare
in this limestone, and that most of them have been found just above the
Waldron shale ; that, further, the lowest fossils which could with certainty
be identified with species from Devonic horizons have usually occurred
25 or 30 feet above the Waldron shale. It is added that the opinion,
frequently expressed, that all the rocks overlying the Waldron shale are
Devonic and that the top of the Waldron shale marks the top of the
Siluric, it is believed will not stand investigation. The Catalogue of the
Fossils of Indiana, furnished by Mr E. M. Kindle, contains no Guelph
species.

In the geologic description of northern Indiana by I. A. Price in the
24th annual report, it is also stated that the Waldron shale does not form
the top of the upper Siluric. At a number of places some 10 or 12 feet
of intervening limestone is to be found between the shale and the base of
the Devonic. This is called the Hartsville bed and is considered as corre-

GUELPH FAUNA IN THE STATE OF NEW YORK

spending stratigraphically to Foerste's Louisville limestone farther south.
It contains no fossils.

We may conclude therefore from the observations here recorded that
no strata which either lithologically or faunistically can be considered as
representing the Guelph have as yet been found in this state.

Michigan. Hall has distinctly stated ' that " at some points on the
northern shore of Lake Michigan . . . there occurs a light colored lime-
stone lying above the Niagara strata, containing generally few fossils and
among them some forms not unlike those of Gait." He also noted this fact
in his description of Pentamerus occidentalism The description
of the rocks of the Niagara group of the upper peninsula of Michigan3
furnishes no additional facts concerning the distribution of these rocks in
that still little known region, but from the fact that the Niagara skirts the
entire south shore of the Upper Peninsula and that the Salina beds appear
along the water edge in some places, as in St Marys Bay, near Mackinac
strait, the probable position of the Guelph outcrops may be located. It is,
therefore, highly probable that the beds with Pentamerus and corals
mentioned by Rominger as occurring at many places on the north shore of
Lake Michigan represent actual Guelph beds. The occurrence of large
Murchisonias, mentioned by the same author, supports this supposition.

Ohio. Guelph fossils are known to occur in Ohio. Hall and Clarke
cite the following brachiopods : 4

Monomerella prisca Billings, Rising Sun, Wood co. ; M. new-
berry i H. & W., Genoa, M. o r t o n i H. & C., Rising Sun, T r imer-
ella acuminata Billings, near Hillsboro, T. grand is Billings, near
Sinking Spring, T. ohioensis Meek, Rising Sun, Genoa and Ottawa
county.

In the second volume of Paleontology of Ohio Hall and Whitfield

'Pal. N. Y. 1859. 3:30.

»Pal. N. Y. 1852. 2:342.

s Rominger, Dr C. Geol. Sur. Michigan. Paleozoic Rocks. 1873. v. 3, pt 2. p. 31.

< Pal. N. Y. 1892. v. 8, pt i.

132

NEW YORK STATE MUSEUM

described and figured the following Guelph forms: Trematonotus
alpheus (Genoa and Springfield), Straparollus niagarensis
(Cedarville), Trochonema pauper (Greenville), C yrtocer as her-
zeri (Cedarville), C. my rice (Yellow Springs), Ph ragmoce ras par-
vum (Cedarville).
Newberry * says :

In the northern part of the state the best exposures of the Niagara are
at Geneva, Elmore and Washington. . . In all this region only the upper
part of the Niagara is seen, the equivalent of the Guelph limestone of
Canada. . . This portion of the formation is a rough, cellular, cream
colored magnesian limestone sometimes mistaken for sandstone, yet being
nearly a typical dolomite in composition. . . The cells and cavities which
are so characteristic of this rock are usually produced through the removal,
by solution, of the shells, of which it once contained great numbers ; hence
all its fossils are represented by casts only.

Among the fossils of the Niagara [Guelph] group which occur most
abundantly in northern Ohio, may be mentioned Megalomus cana-
densis, Tremanotus alpheus, Pleurotomaria solarioides,
Murchisonia macrospira, Trimerella ohioensis, Penta-
merus occidental is, Cypricardites? quadrilatera, Favo-
sites niagarensis, Obolus conradi, etc.

In the southwestern portion of the state one of the best sections is
found at Hillsboro and was thus determined by Edward Orton."

FEET

1 Hillsboro sandstone 30

2 Guelph, Cedarville or Pentamerus limestone - 20

3 Upper or Springfield cliff 45

4 Lower or West Union cliff 45

5 Niagara shales - 60

6 Dayton limestone 5

Newberry says of this : "The upper limestone of the Hillsboro section
is evidently the equivalent of that exposed at Geneva, Elmore, etc., and
like that, represents the Guelph division of the Niagara. It contains
nearly the same fossils at Hillsboro as at Geneva . . . but Pentamerus

'Geol. Ohio. 1873. 1:129.

3 Report of Progress for 1870, p. 301.

GUELPH FAUNA IN THE STATE OF NEW YORK 133

oblongus is much more abundant here than at the north." The
appended list of fossils includes, besides Niagaran corals and crinoids:
Trimerella ohioensis, T. grandis, Obolus conradi, Pen-
tamerus oblongus, Murchisonia macrospira, M. laphami,
Platystoma niagarense, Megalomus canadensis, Trocho-
ceras desplainense, Orthoceras abnorme, Calymmene
niagarensis.

From Dr Orton's original description of this section ' we select the
following data : The Guelph or Cedarville limestone is a massive magnesian
limestone (carbonate of lime 54.25$, carbonate of magnesia 43.23$) varying
in thickness from 20 to 90 feet. Even where the whole of the original
deposit is present, as in sections where it is found inclosed between higher
and lower formations, it has the wide limits already given. It contains
bituminous matter distributed through its substance, and it is pointed out
that the oil-bearing limestones of Chicago belong to the same horizon.
This formation is often destitute of distinct bed lines in its structure. It is
acted on quite easily by atmospheric agencies and by its unequal weath-
ering the faces of the cliffs that it forms are rough and irregular.

It will be noticed that this rock shows notable agreement with the
Guelph rocks of New York.

Pentamerus oblongus is the most common fossil of the Guelph
through this region and further west and it gave the name to the formation.
In New York and Canada this shell is a Clinton and Niagaran species but
in Ohio it appears in full force only in the upper Niagaran limestone and
Guelph. Certain layers are heavily charged with Megalomus while Trim-
erella is also very abundant. Large gastropods and corals show in many
places. The Guelph is overlain by and interstratified with the Hillsboro
sandstone and is the only known instance of distinct shore conditions
recognizable during the Guelph stage.

Orton also described the section at Yellow Springs, Greene co. where

'Rep't of Progress, 1871, p. 278 ft seq.

134

NEW YORK STATE MUSEUM

the Cedarville dolomite shows an exposure of 23 feet, with a total of 40
feet. In connection with this section it is remarked : '

It has received the names of various localities where it is distinctly
shown, being styled the Guelph formation in Canada, the Racine beds or
Milwaukee beds in Wisconsin and the Bridgeport beds in northern Illinois.
In southern Ohio no local name can be selected as appropriate and free
from ambiguity as the Cedarville limestone.

Finally in regard to this formation generally within the state of Ohio,
Dr Orton wrote in 1893 :2

The uppermost division of the [Niagaran] formation is the Guelph
limestone which differs very noticeably in several points from the Niagara
limestone proper. . . It has a maximum thickness in southern Ohio of
200 feet. . . It is either massive or very thin bedded. It is porous to an
unusual extent. It is generally very light in color. It is exceedingly rich
in fossils containing a large number that is thoroughly characteristic.

Unlike the previously named divisions of the Niagara, the Guelph
limestone is as well developed in northern as in southern Ohio in all
respects. Not more than 40 feet «of it are found in its outcrops there, but
the drill has shown several times this amount of Niagara limestone, without
giving us, however, the data needed for referring the beds traversed to their
proper subdivisions. What facts there are seem to point to the Guelph as
the main element in this underground development of this formation in this
portion of the state.

From the foregoing we may conclude that the area in which the
Guelph fauna manifests itself extends from Wayne county, N. Y. westward
to Hamilton Ont, thence northwestward to Cape Hurd and Manitoulin
island, and northward almost to James bay. Here it follows the Niagaran
on the inner side of the vast arc spanned by that formation over the islands
of Georgian bay, the north shore of Lake Huron and north and west
shores of Lake Michigan. Still farther to the northwest, evidence of this
sediment is afforded by the presence of the coral Pycnostylus guel-
p h e n s i s and the Stromatoporoid Clathro^dictyum ostiolatum,
on the west shore of Lake Manitoba.3

1 Geol. Ohio. 1874. 2:674.

"Geol. Ohio, 7:12.

3 Reported by Whiteaves. Paleozoic Fossils. 1893. v. 3, pt 2, p. 46.

GUELPH FAUNA IN THE STATE OF NEW YORK 135

West of Lake Michigan these deposits spread over southern Wisconsin,
northern Illinois and into Iowa, where their extension in this direction is
terminated by the barrier of earlier formations. In Ohio it borders the
north and east shores of the Cincinnati dome.

Over all this amphitheater, bounded without by the Niagaran, we may
conceive of a shallowing sea, dotted with coral banks which must in no
small measure have fringed the shore. Indeed contiguity to the shore line
of the Cincinnati dome is clearly indicated by the Hillsboro sandstone inter-
bedded with the upper dolomites. It was an almost inclosed sea, its open-
ing being probably through the narrow way toward the north and northwest,
a region which still holds the clue to many of our exotic faunas.

In this connection it appears also significant that in the terminal beds
of the upper Siluric of Gothland a fauna appears which contains the genera
characteristic of the Guelph and often species which are hardly distinguish-
able. These are specially contained in the beds f, g, h ; f being character-
ized1 as limestone beds composed of crinoids and corals ; g, large banks of
Megalomus and Trimerella, and h, Cephalopodan and Stromatopora beds.
In looking over these lists one can not fail to conceive the idea that the
much richer fauna of these beds contains a vicarious fauna of the American
Guelph, for we find there Monomerella, Trimerella (with three species),
with the absence of the majority of the Wenlock forms ; Megalomus among
the lamellibranchs ; Trematonotus and a very large number of cephalopods
and gastropods, including Pleurotomaria, Murchisonia, Loxonema, Trochus,
Pycnomphalus, Horiostoma, etc. ; also Stromatoporas.

The appearance of such peculiarly adapted forms as the Trimerellas
and Megalomus, at corresponding horizons and in similar associations, is
certainly very suggestive not only of the presence of the identical facies,
but also of faunistic intercourse between the two seas.

There is a generally recognized distinction between the rich Siluric
faunas of northern Europe and those of Bohemia and the Mediterranean

' See Swedish State Mus. Pal. Dep't. ed. List of the Fossil Faunas of Sweden, II, Upper
Siluric.

136 NEW YORK STATE MUSEUM

region. Kayser has recently expressed1 this distinction by terming the
former the normal facies or that appertaining to the oceans at large, while
the latter is to be regarded as having the value of a local facies. The
former it is that is more widespread throughout the world and which we
have constantly growing evidence for believing has entered the interior sea
of America by way of northern Canada. Its incarceration in the Ameri-
can paleozoic mediterranean has doubtless superinduced a measure of
provincial characteristics in some of the minor faunas but the features we
find in the Guelph common to those of the Scandinavian faunas appertain
to the marine life of the inclosed seas of late Siluric time.

The Coralline or Cobleskill limestone. This study of the Guelph
fauna and stratigraphy has thrown important light on the proper construc-
tion of the fauna of the Coralline limestone of eastern New York. This
formation was first recognized as an element in the succession by John
Gebhard, and by Prof. Hall was considered an eastern continuation of the
Niagaran limestone. We have elsewhere suggested that the objectionable
character of its designation may be remedied by employing for it the term
Cobleskill limestone, as along this creek in Schoharie county, N. Y., the
section of the formation is typically expressed. We do not here propose
entering on an extended discussion of this fauna and its stratigraphic rela-
tions. These matters, which we have had under consideration for some
years, have recently been made the subject of careful and extended investi-
gation by C. A. Hartnagel, of the staff of this division and we have invited
him to insert here the following brief statement of his preliminary con-
clusions so far as they bear on the relation of this fauna to the Guelph.

The Cobleskill formation in its typical development at Schoharie and
Howes Cave, Schoharie co. consists of a massive layer of dark gray, some-
what magnesian limestone averaging 6 feet in thickness. Above this lime-
stone and clearly distinguished from it by a change in lithologic character,
lie the Rondout beds, 40 feet thick and marked by basal layer of " cement
rock," 6 feet thick. Above this are 45 feet of typical Manlius limestone.
Underlying the Cobleskill and resting upon the Lorraine beds are 30 feet

'Geologische Formationskunde. ed. 2. 1902. p. 102.

GUELPH FAUNA IN THE STATE OF NEW YORK 137

of green argillaceous shales which doubtless pertain to the Salina stage.
The Cobleskill or Coralline limestone fauna was early described by Hall
who regarded it the eastern representative of the Niagaran group as then
known in western New York. He interpreted the underlying shales as of
Clinton age. Recent examination however clearly indicates that the Cobles-
kill limestone as shown in the section described pertains to an age later
than Salina, as has been suggested by Schuchert.

One of the marked differences between the faunas of the Niagaran of
New York and the Cobleskill is the presence in the latter of quite an exten-
sive gastropod and cephalopod fauna — one of the features which strongly
affiliates it with the Guelph. And, indeed, Hall, in the original descriptions
of Pleurotomaria subdepressa and Murchisonia terebra-
1 i s, notes in each case a similarity to forms described from the Guelph.

An interesting feature of some of the gastropods from the Cobleskill
is that in form they are sinistral. Pleurotomaria subdepressa
mentioned above belongs to this class. Another species is distinguished
from Poleumita crenulata Whiteaves (Guelph), only by its sinistral
form. Other specimens of the genus Pleurotomaria have been found which
in size and form are similar to the Guelph species, but the delicate surface
markings often so well preserved in the Guelph dolomites and upon which
specific determinations to a certain degree are dependent, have not yet been
ascertained in the Cobleskill limestone specimens and thus specific compari-
sons become unsatisfactory. Kionoceras darwini Billings occurs at
Schoharie, and in the western extension of the Cobleskill fauna on Fronte-
nac island, Cayuga lake, where Orthoceras trusitum Clarke &
Ruedemann and Gomphoceras septoris Hall (Guelph) are also
found. In Schoharie county mature specimens of Ilioniagaltensis
Whiteaves occur. Associated with them are forms which in outline and
dimensions approach Ilionia canadensis Whiteaves and to that
species they are provisionally referred. Spirifers from the Guelph have
obsolescent plications and a sinus similar to Spirifer crispus van
corallinensis Grabau.

There are other species common to these faunas but they are mostly
forms occurring also in the Niagaran and indicative solely of a late Siluric
stage.

EXPLANATION OF PLATES

140

NEW YORK STATE MUSEUM
PLATE I

Enterolasma cf. caliculus Hall (sp.)

Page 24

FIG.

i The exterior, natural size

Zaphrentis cf. racinensis Whitfield

Page 23

2, 3 Lateral and basal view of an internal cast of the calyx. Natu-
ral size

Heliophyllum sp. indet.

Page 28

4 Internal cast of a specimen. Natural size

5 Same, X2 ; to show the impressions of the denticulated carinae

on the septa

Syringopora infundibulum Whitfield

Page 35

6-9 Sections obtained on a polished surface, to show the spini-
form septa, funnel-shaped tabulae and transverse, hollow
connecting processes. X2

GUELPH FAUNA

Memoir 5. N.Y State Museum

Plate 1

G.S Barkentm del

J. B. Lyon Co. State Printer

Phil. Ast.hth.

FIG.

GUELPH FAUNA IN THE STATE OF NEW YORK 141

Clathrodictyum ostiolatum Nicholson

10 Surface view of specimen, showing the characteristic botryoidal

surface. Natural size
1 1 Section, shown on broken side of same specimen, and exhibit-

ing the calcareous laminae. Natural size

12 Thin section of a portion, X2, showing the laminae and inter-

mediate vertical dissepiments

Stromatopora galtensis Dawson (sp.)

Page 36

13 A fragment exhibiting the astrorhizae. X3

The originals of fig. 1-5, 10-13 are from the Guelph bed at
Rochester (Arey collection) ; those of fig. 6-9 from the Upper
Shelby bed (N. Y. State Museum).

142

NEW YORK STATE MUSEUM
PLATE 2

no.
I

Monomerella noveboracum sp. nov.

(See plate 3 and plate 4, fig. 38)
Page 39

Cardinal area of a pedicle valve, showing the coarse stria-
tions of the pedicle groove, the lateral slopes, the character
of the cardinal slope and cardinal groove, and the narrow
but high cardinal buttress

A pedicle valve with very high and relatively narrow cardinal
region and more depressed median area. From a gutta-
percha squeeze of the natural impression

The exterior of the pedicle valve of an old individual with
very irregular squamous surface. From a gutta-percha
squeeze of a natural impression ; slightly restored at the
anterior and posterior ends

The exterior of a younger pedicle valve, showing the growth
lines. Also from a gutta-percha impression

GUELPH FAUNA

Memoir 5. N.Y. State Museum.

Plate. 2

G.S.Barkentm.del

J. B. Lyon Co. State Printer

Phil. Ast.lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 143

•IG.

5 The interior of a pedicle valve, with the subdivisions of the

crescent sharply defined and showing the extent of the
cardinal buttress and the low anterior septum. Slightly
restored at the umbo. From a gutta-percha impression of
the internal cast represented on plate 3, fig. 7

6 Internal cast of part of the pedicle valve of an old individual,

showing very strongly marked lateral crescent and platform
muscle scars, and short but broad platform vaults
All specimens are drawn in natural size and come from

the Lower Shelby bed at Shelby, Orleans co. N. Y. Originals

in N. Y. State Museum.

144

NEW YORK STATE MUSEUM
PLATE 3

Monomerella noveboracum sp. nov.

(See plate 2 and plate 4, fig. 38)

Page 39
no.

i, 2 Two views of the cardinal region of the brachial valve, show-
ing the hinge line and the strongly developed crescent.
From a gutta-percha squeeze of a natural impression
3 An internal cast of a brachial valve, with the muscular impres-
sions of the platform strongly denned, showing the short
platform vaults

4, 5 The interior of a large brachial valve, shown as a natural
cast (fig. 5) and as a gutta-percha squeeze taken from this
cast (fig. 4). These show well the broad form of the valve,
the muscular impressions, the form of the platform and the
anterior septum.

GUELPH FAUNA

Memoir 5. N Y. State Museum

Plate 3

G S.Barkentm del

J.B Lyon Co. State Printer

Phil. Aat.lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 145

PIC.

6 Lateral view of the two valves in apposition reconstructed

from the brachial and pedicle valves figured on this plate,
showing the long straight cardinal region, the nearly
straight profile of the pedicle valve and the more convex
contour of the brachial valve

7 An internal cast of a large pedicle valve, showing the high

cardinal area, the very deep platform vaults and the charac-
teristic markings of the platform, as well as the impressions
of the sides of the crescent, and the anterior septum
All specimens are drawn natural size, and are from the Lower
Shelby bed at Shelby N. Y. Originals in N. Y. State Museum.

146

NEW YORK STATE MUSEUM
PLATE 4

Cornulites arcuatus Conrad

Page 105

IG.

1 Internal cast of a stout, rapidly tapering specimen. Natural

size. Rochester (Arey collection)

2 Internal cast of a slender, slightly arcuate specimen from a

gutta-percha squeeze of a natural impression. Natural size.
Lower Shelby bed (N. Y. State Museum)

3 A specimen with slightly different character of the annula-

tions. X2. Rochester (Arey collection)

4 A specimen retaining part of the shell and natural surface.

Upper Shelby bed (N. Y. State Museum)

5 An internal cast of a large specimen. Natural size. Rochester

Crania sp.

Page 38

6 Single specimen observed. X2. Rochester (Arey collection)

GUELPH FAUNA

Memoir 5. NY State Museum

Plate 4

G S BarUentm.del

B Lyon Co. State Printer

Phil. Aat.lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 147

Dalmanella cf. hybrida Sowerby (sp.)

Page 42
FIG.

7, 8 Two views of a small shell, doubtfully referred to this species.
x5. Rochester (Arey collection)

Dalmanella cf. elegantula Dalman (sp.)

Page 41

9 Single specimen observed. X3. Rochester (Arey collection)
Spirifer crispus (Hisinger) Hall

Page 42

10 Internal cast of the ventral valve of a specimen with obscure
ribs. Natural size. Upper Shelby bed (N. Y. State
Museum)

11, 19, 20 Three views of a well preserved example of the prevailing

expression of the species, showing the character of the
surface. x2. Upper Shelby bed (N. Y. State Museum)

12, 13, 1 8 Three views of the internal cast of a similar form. xz.

Rochester (Arey collection)
14, 1 6, 17 Three views of a finely preserved specimen from the same

locality. X3

1 5 Enlargement of the surface, to show the characteristic papil-
lose sculpture of the species. x5- Rochester (Arey col-
lection)

Spirifer cf. bicostatus (Vanuxem) Hall

Page 44

21 Internal cast of a ventral valve. x2. Rochester (Arey

collection)

22 Lateral view of a shell with similar characters. Natural size.

Upper Shelby bed (N. Y. State Museum)

Rhynchotreta cuneata americana Hall

Page 46

23-25 Three views of a specimen, natural size. Upper Shelby
bed (N. Y. State Museum)

148

NEW YORK STATE MUSEUM

Camarotoechia (?) indianensis Hall

Page 46

26, 27 Two views of a gutta-percha squeeze from a natural impres-
sion. Natural size. Lower Shelby bed (N. Y. State
Museum)

Camarotoechia (?) neglecta Hall

Page 45

28-30 Three views of a specimen, natural size. Rochester (Arey

collection)

31 View of the ventral valve of an excellently preserved typical
specimen. x2. Rochester (Arey collection)

Whitfieldella nitida Hall

Page 44

32i 36, 37 Three views of a broad and flat specimen, an internal cast,
showing pallial sinuses on pedicle valve. X2

33. 34. 35 Three views of a higher and thicker specimen. X2. Roches-
ter (Arey collection)

Monomorella noveboracum sp. nov.

(See plates 2 and 3)
Page 39

38 Internal cast of a very high pedicle valve with extremely long
platform vaults. Natural size. Lower Shelby bed (N. Y.
State Museum)

GUELPH FAUNA IN THE STATE OF NEW YORK

149

PLATE 5

123 5 ~B

00-00

Modiolopsis sp.

'1C.

1 Internal cast of left valve. X2

2 Same of a right valve, showing posterior cartilage pit. xa

3 Internal cast of a larger individual with suborbicular

outline. X2

5 Internal cast of a small, more oblique specimen with long

posterior wing, xa
All are from the Guelph at Rochester (Arey collection)

Pterinea subplana Hall (sp.)

Page 49

4 Internal cast of a left valve, natural size. Upper Shelby

bed (N. Y. State Museum)

Pterinea undata Hall (sp.)

Page 50

6 Internal cast of a left valve. X2. Upper Shelby bed (N. Y.

State Museum)

I5O NEW YORK STATE MUSEUM

Conocardium sp.

Page 50
no.

7 View of a left valve. X3. Rochester (Arey collection)
Mytilarca eduliformis sp. nov.

Page 47

8-1 o Three views of the type specimen. X2. Lower Shelby bed
(N. Y. State Museum)

Mytilarca acutirostrum Hall (sp.)

Page 48

11 Internal cast of a high left valve. Natural size

12 Another more gibbous specimen, showing the posterior lateral

teeth. Natural size

Both specimens are from the Lower Shelby bed (N. Y. State
Museum).

Bellerophon shelbiensis sp. nov.

Page 51

13 Ventral view of a specimen, apertural part broken away.

Natural size

14 Dorsal view of an internal cast, showing aperture and aper-

tural emargination. Natural size

1 8 Lateral view of same specimen, showing cast of umbilicus.

Natural size

15 Broken specimen, showing inner volution and umbilical wall.

X2

1 6, 17 Two views of a large specimen, showing aperture and dorsal
keel. Natural size

19 View of inner side of volution, showing slit band of preceding

volution. Natural size

All specimens are from the Lower Shelby bed (N. Y. State
Museum).

GUELPH FAUNA

Memoir 5. N Y. State Museum

Plate 5

W S.Barkentm.del.

J. B. Lyon Co. State Printer

Phi!. Ast.lilh.

FIG.

GUELPH FAUNA IN THE STATE OF NEW YORK 151

Trematonotus alpheus Hall

(See plate 6, fig. 1-9)

20 Dorsal view of sculpture cast, showing peristome. Natural

size. Rochester (Arey collection. Same specimen as plate
6, fig. i)

21 Dorsal view of internal cast, showing dorsal perforations and

smooth internal surface. Natural size

23 Lateral view of same cast, showing umbilicus and inner volu-
tions. Natural size. Lower Shelby bed (N. Y. State
Museum)

22 Fragment of a specimen with very strongly developed revolv-

ing ridges and wide umbilicus. Natural size. Rochester
(Arey collection)

152

NEW YORK STATE MUSEUM
PLATE 6

Trematonotus alpheus Hall

(See plate 5, fig. 20-23)
Page 54

Lateral view of a specimen, showing the revolving ribs and
the broad transverse folds

Lateral view of a specimen, showing distinctly the dorsal keel
interrupted by the perforations, the alternation of the
revolving ribs and the wide and deep umbilicus. From a
gutta-percha impression of a natural mold

A natural cast of the exterior of the apertural part of the last
volution and of the interior of the penultimate volution,
showing the dorsal perforations of the last volution and the
smooth internal surface of the earlier volutions

An exterior dorsal view of a shell, showing distinctly the inter-
ruptions of the revolving ribs by concentric growth and the
widening of the ribs upon the lip. From a gutta-percha
squeeze of a natural impression

OUELPH FAUNA.

Memoir 5.N.Y. State Museum

Plate 6

G S.Barkentm del

J.B.Lyon Co, State Printer

Phil. Ast.lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 153

PIG.

5 A natural cast of the exterior of an older individual, showing

a more nodose character of the revolving ribs upon the
outer lip and the cast of one of the innermost volutions

6 The exterior of the last volution of a gerontic specimen, show-

ing a partial suppression on the outer lip of the smaller ribs
which are made much too strong in the drawing. From a
gutta-percha impression of a natural mold

7 Ventral view of the internal cast of the last volution, showing

the ventral depressed zone

8 Section of an internal cast, showing the relative width and

hight of the volutions

9 Another section of an internal cast, exhibiting a somewhat

asymmetric arrangement of the inner volutions
All specimens drawn natural size. With the exception of the
original of fig. i which is from the Guelph at Rochester (Arey
collection), all are from the Lower Shelby bed (N. Y. State
Museum).

154

NEW YORK STATE MUSEUM
PLATE 7

Eotomaria kayseri sp. nov.

(See plate 8, fig. i)
Page 70

1 Lateral view of the internal cast

Coelidium macrospira Hall (sp.)

(See plate 10, fig. 13)
Page 65

2 Lateral view of a specimen with angular volutions, showing

distinctly the surface characters

3 Young, somewhat rapidly widening specimen with rounded

volutions (M. logani)

4 A still younger specimen, showing the same characters

5 A section of the specimen figure 2, showing the perforate axis

of the shell

6 A nearly complete example, showing a gradual change from

the round to more angulated volutions. From a gutta-
percha squeeze of a natural impression

GUELPH FAUNA

Memoir 5. N .Y State Museum

Plate 7

WS Barkentin.del.

J. B. Lyon Co, State Printer

Phil. Ast.lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 155

FIG.

7 An internal cast of the shell, showing the rounded character of

the volutions (M. logani)

8 Another internal cast of a shell, showing the rounded volu-

tions, which are all represented as too angular

Coelidium cf. vitellia Billings (sp.)

Page 67

9 Section of the shell, showing the wide perforation of the

axis ; rather badly restored at the apex
10 Exterior view of the same specimen

All specimens are drawn natural size and are from the Guelph
beds at Rochester (Arey collection).

'56

NEW YORK STATE MUSEUM
PLATE 8

Eotomaria kayseri sp. nov.

(See plate 7. fig. i)

Page 70
FIG.

1 Basal view of the specimen represented on plate 7, showing

the narrow umbilicus

Eotomaria areyi sp. nov.

(See figures, p. 69)

Page 68

2 Basal view of the type specimen represented on p. 69, exhib-

iting the narrow umbilicus and the growth lines

Euomphalus fairchildi sp. nov.

Page 75

3 Lateral view of the type specimen of the species, showing

the forward curvature of the growth lines

4 Upper side of the same specimen

GUELPH FAUNA,

Memoir 5. N .Y State Museum

Plate 8

G.S.Barkentm del

J. B. Lyon Co. State Printer

Phil. Ast.lilh.

GUELPH FAUNA IN THE STATE OF NEW YORK 157

Hormotoma whiteavesi sp. nov.

Page 72
FIG.

5 Last volutions of a very large individual with strongly marked

sculpture of the surface and slit band

6 A younger, very slender specimen, showing the strongly

recurving growth lines ~
7, 9 Two views of a nearly complete specimen in solid chert with

very faint indications of the growth lines and slit band
8 View of a very large example, showing the long, narrow,

prolonged aperture

All specimens are drawn natural size, and are from the
Guelph beds at Rochester (Arey collection).

158

NEW YORK STATE MUSEUM
PLATE 9

Poleumita scamnata sp. nov.

Page 60

i Lateral view of a specimen with depressed spire

3, 5 Three views of an individual with high spire

4, 7 Two views of an average specimen

6 Umbilical view, showing the size of umbilicus
8 Apical view of a young specimen, showing distinctly the sur-
face sculpture of the early volutions. X2

10 Umbilical view of a specimen with very distinct sculpture of
the basal region

12 Enlargement of the surface. x3

13 Umbilical view of an older individual, showing the wider

interval between the revolving lines near the umbilicus.

14 Apical view of an individual with very sharp revolving and

indistinct transverse lines. From a gutta-percha squeeze
of a natural impression (see fig. 12)

OUELPH FAUNA

Memoir 5. N.Y State Museum

Plate 9

G S Barkentm del

B.Lyon Ca State Printer

Phil. Ast.lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 159

FIG.

15 Enlargement of part of a specimen with extremely coarse

revolving and irregular transverse lamellose growth lines
on the last volution

Poleumita crenulata Whiteaves (sp.)

Pat'e 64

9, 1 1 Two views of a young specimen, exhibiting very sharp sculp-
ture lines

1 6 Apical view of a typical individual. From a gutta-percha

squeeze of a natural cast. Lower Shelby bed (N. Y. State
Museum)

17, 1 8 Two views of a specimen with very sharp, distant, transverse
lines, showing also the gradual suppression of the revolving
ridges upon mature volutions

19 Enlargement of the sculpture on the basal side of a large

individual, showing the coarse growth lines and the faint
revolving ridges. X3

20 Individual retaining the revolving ridges upon the last

volution

21 A very large individual, showing distinct gerontic characters

upon the last volution. From a gutta-percha squeeze of a
natural impression. Lower Shelby bed (N. Y. State
Museum)

22 Natural section of the volutions

23 Lateral view of an individual with depressed spire

24 Apical view of a specimen, showing strong contrast between

the ornament of the last and early volutions
All figures are natural size and all originals are from the
Guelph at Rochester, where not otherwise stated.

i6o

NEW YORK STATE MUSEUM
PLATE 10

Poleumita (?) sulcata Hall (sp.)

Page 62

FIG.

i, 2 Two views of a typical specimen. Natural size
3, 4 Profile and umbilical views of another specimen. Natural size.
Rochester (Arey collection)

Trochonema cf. fatuum Hall

Page ^s

5 Lateral view of the only specimen observed. Natural size.

Upper Shelby bed (N. Y. State Museum)

Lophospira bispiralis Hall (sp.)

Page 71

6 Apical part of a specimen, showing distinctly the carinae.

From a gutta-percha impression of a natural mold. X2.
Lower Shelby bed (N. Y. State Museum)

7, 8 Two older individuals which show the structure of the slit
band and the gradual obsolescence of the carina on the
upper side of the volution. Natural size. Rochester

GUELPH FAUNA

Memoir 5. N .Y. State Museum

Plate 10

G S Barkentm del

J..B. Lyon Co. State Printer

W S BarUentm.lith.

GUELPH FAUNA IN THE STATE OF NEW YORK l6l

FIG.

9 Young individual with very strongly marked carinae and slit
band. Natural size. Rochester

Eotomaria galtensis Billings (sp.)

Page 70

10-12 Three views of an internal cast with parts of the shell
preserved. Natural size. Upper Shelby bed (N. Y. State
Museum)

Coelidium macrospira Hall (sp.)

(See plate 7, fig. 2-8)
Page 65

13 Gutta-percha impression of an internal cast of a young indi-
vidual. Lower Shelby bed (N. Y. State Museum)

Diaphorostoma niagarense Hall (sp.)

Page 59

14, 15 Two views of a very small specimen. x3. Fig. 15 is slightly
restored at the apex. Rochester (Arey collection)

1 6 An individual from the Upper Shelby bed. From a gutta-

percha impression. X2. (N. Y. State Museum)

Eotomaria durhamensis Whiteaves (sp.)

Page 68

17 Apical part of an individual. Natural size. Rochester (Arey

collection)

Macrochilina sp. indet.

Page 74

18 Single individual observed. x5. Rochester (Arey collection)

Dawsonoceras annulatum americanum Foord

(See plate n, fig. i)

Page 81

19 Enlargement of surface of original of fig. 20. X5

20 A young individual, with extremely close arrangement of the

annulations. Natural size. Rochester (Arey collection)

I 62 NEW YORK STATE MUSEUM

FIG.

21 Young individual, showing the longitudinal lines with marked

distinctness. Natural size. Rochester (Arey collection)

Kionoceras darwini Billings (sp.)

(See plate n, fig. 6; plate 12, fig. 1-8)
Page 84

22 Fragment of shell, showing both the longitudinal ribs and

transverse lines. Rochester (Arey collection)

Kionoceras medullare Hall (sp.)

Page 86

23 Fragment of shell, showing the ornament ; from a gutta-percha

impression of a natural mold. Natural size. Lower Shelby
bed (N. Y. State Museum)

Orthoceras trusitum sp. nov.

(See plate 13, fig. i-io)
Page 77

25 Internal cast of a slightly curved individual with very closely

arranged septa. Natural size

26 Young individual, showing the smooth surface and the depth

of the camerae. Natural size. Rochester (Arey collection)

Orthoceras crebescens Hall

(See plate n, fig. 2-5)
Page Bo

24 Internal cast of camerae and siphuncle of young specimen,

referred with some doubt to this species. Natural size

27 Septal view of specimen figured on plate n, fig. 2, showing

the section of conch, position and size of siphuncle. Natu-
ral size

28 Septal view of specimen figured on plate 11, fig. 3. Lower

Shelby bed (N. Y. State Museum)

164

NEW YORK STATE MUSEUM
PLATE it

Dawsonoceras annulatum americanum Foord

(Sec plate 10, fig. 19-21)

Page So
FIG.

1 A large individual from the Lower Shelby bed.

Orthoceras crebescens Hall

(Set plate 10, fig. 24, 27, 28)
Page 80

2 Fragment of internal cast, showing septal sutures and obscure

longitudinal ridges

3 Internal cast of a fragment of an old individual, showing

curved septal sutures, relatively deep camerae and septa
and low longitudinal ribs.

4 An internal cast of the living chamber and camerae of an old

individual, showing the sinuate growth lines on living
chamber and shallow gerontic chambers

GUELPH FAUNA

Memoir 5. N.Y. State Museum

Plate 1 1

G S Barkentm del

J. B. Lyon Co. State Printer

W S. Barkentm. hth.

GUELPH FAUNA IN THE STATE OF NEW YORK 165

no.

5 Section through lower part of individual represented in fig. 2,

showing the curvature and depth of camerae and slightly
expanded siphuncle.

Kionoceras darwini Billings (sp.)

(Set plate 10, fig. 22; plate 12, fig. 1-8)
Page 84

6 A very large individual, retaining the longitudinal ribs to

mature age. From a gutta-percha squeeze of a natural
impression

All figures are natural size. All originals are from the Lower
Shelby bed (N. Y. State Museum).

1 66

FIG.

I, 2

5
6

NEW YORK STATE MUSEUM
PLATE 12

Kionoceras darwini Billings (sp.)

(See plate 10, fig. 22; plate n, fig. 6)
Page 84

Two views of a young specimen with excellently preserved
surface sculpture

Fragment showing obscure transverse undulations and alter-
nating ribs

Specimen showing the depth of the camerae and septa

Originals of fig. 1-4 from Rochester (Arey collection).

Septal view of individual represented in fig. 6

Internal cast of older specimen, showing part of the living

chamber and the increase in the depth of the chambers
Internal cast of specimen with gerontic approach of the septa

and somewhat oblique septal sutures

GUELPH FAUNA

Memoir 5. N .Y. State Museum

Plate 12

G S.Barkentm del.

J. B Lyon Co. State Printer

W.S Barkentm lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 167

10.

8 An individual with strong subequal longitudinal ribs. From

a gutta-percha impression

Originals of fig. 5-8 are from the Lower Shelby bed (N. Y.
State Museum).

Orthoceras rectum Worthen

Page 78

9 Internal cast of a large specimen, showing the great depth of

the camerae. Lower Shelby bed (N. Y. State Museum)

i68

NEW YORK STATE MUSEUM
PLATE 13

Orthoceras trusitum sp. nov.

(See plate 10, fig. 25, 26)
Page 77

FIG.

1 Fragment preserving the longitudinally lineated surface

2 Internal casts, showing the numerous, shallow camerae and

straight transverse suture lines

3 Young individual, showing the slenderness of conch

4 Internal cast, showing undulating septal sutures

5 Septum with excentric siphuncle

6 Broken internal cast, showing the depth of camerae and the

tubular siphuncle

7 Septum, showing the circular section of conch and subcentral

location and relative size of siphuncle

8 Section of specimen represented in fig. i, showing the rela-

tively great thickness of conch

9 Part of living chamber, showing longitudinal lineation

GUELPH FAUNA

Memoir 5. N Y. State Museum

Plate 13

G S Barkentin.del.

J.B.Lyon Co. State Printer

W S Barkentm lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 169

FIG.

10 Internal cast of an older individual with deeper chambers and

obscure longitudinal ribs

All figures are natural size. The originals of fig. 1-5, 7-9
are from Rochester (Arey collection) ; those of fig. 6 and 10 from
the Lower Shelby bed (N. Y. State Museum).

Cyrtoceras cf. brevicorne Hall

Page 89

1 1 Fragment showing the living chamber and sinuous growth

lines. Natural size. Rochester (Arey collection)

12 Mold and internal cast of a fragmentary specimen, showing

the amount of curvature and the unequal depth of the
camerae. Lower Shelby bed (N. Y. State Museum)

Poterioceras sp.

Page 97

13-16 Four views of the internal cast of the living chamber of the
only specimen observed, showing the contraction of the
chamber and the submarginal position of the nummuloidal
siphuncle. Lower Shelby bed (N. Y. State Museum)

170

NEW YORK STATE MUSEUM
PLATE 14

3 4

Poterioceras sauridens sp. nov.

Page 93

1-3 Three views of an internal cast of the living chamber and the
two latest camerae, showing the aperture, contraction
of living chamber, transversely oval section and position of
siphuncle

4 Ventral view of another internal cast, showing the depth of

the septum

5 Internal cast and mold of a nearly complete individual, show-

ing hyponomic indenture of aperture, a greater number
of camerae and form of conch

Originals of fig. 1-5 are from the Lower Shelby bed (N. Y.
State Museum).

GUEL.PH FAUNA

Memoir 5. N.Y. State Museum

Plate 14

W S.Barkentm del et. lilh.

J. B. Lyon Co. State Printer

TSE

;ltV

GUELPH FAUNA IN THE STATE OF NEW YORK 171

FIG.

6-9 Four views of a partially crushed specimen which shows the
surface characters of the species and the form of the living
chamber. Fig. 9 is from a gutta-percha squeeze of the
mold and shows the hyponomic curve of the growth lines
on the ventral side. Rochester (Arey collection)

10 Interior cast and mold of a specimen, retaining the siphuncle

in position

1 1 The siphuncle of the same specimen. X3.

12-15 Four views of the most complete specimen observed. From
a sulfur cast of a natural mold in the rock

1 6 Mold and cast, showing the thickening of the conch near the

aperture

17 Specimen which shows the hyponomic sinus of the growth

lines on the ventral side and the contraction of the shell
near the aperture. From a gutta-percha impression of a
natural mold

1 8 Internal cast of a large specimen, showing a broad and low

living chamber and shallow septum

19 Septal view of same

All figures except u are natural size. Originals of fig. IO-IQ
are from the Lower Shelby bed (N. Y. State Museum).

172

NEW YORK STATE MUSEUM
PLATE 15

Cyrtoceras arcticameratum Hall

(See plate 16, fig. 1-7)
Page 87

FIG.

1 A specimen retaining the shell and exhibiting the character

of the surface

2 A specimen with closely arranged septa

Cyrtoceras erodes Billings

Page 88

3 Septal view of a specimen, showing the marginal position of

the siphuncle and the difference in curvature between the

inner and outer sides
4, 5 Two views of an internal cast, referred with some doubt to

this species, showing a rapidly expanding living chamber

and subcircular section
6-8 Three views of an internal cast, showing the depth of the

camerae and direction of the sutures
9 A specimen exhibiting the siphuncle

GITKLPH FAUNA

Memoir 5. N .Y. State Museum

Plate 15

W • Bai kem n del

J. B. Lyon Co. State Printer

GUELPH FAUNA IN THE STATE OF NEW YORK 173

PIG.

10, ii Internal cast of a large specimen, referred with doubt to this

species, possessing a strongly contracted living chamber
All figures are natural size. The originals of fig. 1-3, 6-9
are from Rochester (Arey collection) ; those of fig. 4-5, 10, 1 1
are from the Lower Shelby bed (N. Y. State Museum).

174

NEW YORK STATE MUSEUM
PLATE 16

Cyrtoceras arcticameratum Hall

(See plate 15, fig. i, 2)
Page 8'

1-4 Four views of the most complete specimen observed ; showing

the degree of curvature and rate of expansion of the conch

5 Septum of a specimen, showing the marginal position of the

siphuncle and a subcircular section

6, 7 Two sections of another specimen with longer dorsoventral
axis

Cyrtoceras bovinum sp. nov.

(See plate 18, fig. 5, 6)
Page go

8, 9 Two views of a specimen, showing the rapid expansion of the

shell, depth of camerae and surface characters
All figures are drawn natural size, and are from Rochester
(Arey collection).

GUELPH FAUNA,

Memoir 5. N.Y State Museum.

Plate 16

W S Barkentin.del.

J. 8 Lyon Ca State Printer

Phil. Aat.lith.

1 76

i

2

3
4
5

NEW YORK STATE MUSEUM
PLATE 17

Cyrtorhizoceras curvicameratum sp. nov.

Page 90

Dorsal view of internal cast of living chamber (see fig. 7)
Section of aperture of same, showing the lateral compression

of the living chamber

Septal view of same, showing marginal position of siphuncle
Septal view of another, somewhat rounded form (see fig. 6)
Specimen which shows the direction of septal sutures, depth

of camerae, position of, and slightly expanded siphuncle
Internal cast, showing the living chamber and the ventral lobe

of the sutures
Internal cast of living chamber of large individual, showing

the aperture, the strong curvature of the last septum and the

curvature of the chamber

GUEIJPH FAUNA

Memoir 5. NY State Museum

Plate 17

G S.Barkentm.del.

J. B. Lyon Ca State Printer

W S.Barkentm lith.

FIG.

GUELPH FAUNA IN THE STATE OF NEW YORK 177

8-1 o Three views of the most complete specimen observed ; show-
ing the depth of the camerae, the ventral lobes of the
sutures and the low longitudinal surface ribs
The originals of all drawings are from the Lower Shelby bed

(N. Y. State Museum).

1 78

NEW YORK STATE MUSEUM
PLATE 18

Gyroceras farcimen sp. nov.

Page 92
FIG.

1-3 Three views of an internal cast, showing the sutures, depth of
camerae, position of siphuncle and circular section of conch

4 Fragment, showing the curvature of the conch and the smooth

surface. From a gutta-percha impression of a natural mold

Cyrtoceras bovinum sp. nov.

(See plate 16, fig. 8, 9)
Page 90

5 Specimen retaining the surface sculpture

6 A large individual, showing the curvature and expansion of

the conch, direction of sutures and depth of camerae
All figures are natural size. The originals of fig. 1-4 are
from the Lower Shelby bed (N. Y. State Museum) ; those of
fig. 5, 6 from Rochester (Arey collection).

GUELPH FAUNA

Memoir 5 N.Y State Museum

Plate IX

W S Rarkentin. del et lith.

J. B. Lycn Co. State Printer

i3o

NEW YORK STATE MUSEUM
PLATE 19

Protophragmoceras patronus sp. nov.

Page 97

PIG.

i, 2 Two views of the only specimen observed. Natural size.
Lower Shelby bed (N. Y. State Museum)

GUELPH FAUNA

Memoir 5. N .Y State Museum

Plate 19

G S.Barkentm.del.

J. B. Lyon Co. State Printer

W S.Barkentin.lith.

182

FIG.
I

NEW YORK STATE MUSEUM
PLATE 20

1

Trochoceras costatum Hall

Page 103

Specimen showing the rate of expansion, curvature of conch
and the character of the costae. From a gutta-percha
impression of a natural mold

An individual which shows the living chamber and the curva-
ture and depth of the last septum. The costae on the
living chamber are drawn somewhat too strong.

Trochoceras desplainense McChesney

Page ioo

Enlargement of surface (x3) to show the fine transverse and
longitudinal lineation. From a gutta-percha impression of
a natural mold

Internal cast of specimen, showing the aperture, living cham-
ber and septal sutures of an early whorl

Specimen with strongly developed costae and growth lines

GUELPH FAUNA

Memoir 5. NY State Museum

Plate 2 0

G S.Barkentm del.

J. B. Lyon Co.. State Printer

Phil. Ast, et
W. S.Barkentm lith.

GUELPH FAUNA IN THE STATE OF NEW YORK 183

FIG.

6 A nearly complete individual, showing the gradual obsoles-

cence of the costae on the living chamber. From a gutta-
percha impression of a natural mold

7 An older, nearly complete individual, showing the tangential

direction of the gerontic portion of the conch

8 Section showing the lateral compression of the conch and the

position of the siphuncle

9 Part of a mature individual, showing the size and expansion

of the living chamber, and the surface sculpture on the

mature shell

All figures except 3 are natural size. The originals of fig. i,
2, 4, 6 and 8 are from the Lower Shelby bed (N. Y. State
Museum) ; those of fig. 3, 5, 7 and 9 from Rochester (Arey
collection).

ib'4

NEW YORK STATE MUSEUM
PLATE 21

Phragmoceras parvum Hall & Whitfield

Page 99

FIG.

i Lateral view of a relatively large specimen with well preserved

surface sculpture

2, 3 Two views of a specimen, showing the curvature of the apical
part, the last camerae, the living chamber and the different
direction of the septal sutures and surface lines
4-8 Five views of a specimen, showing the long and narrow hypo-
nomic area of the contracted aperture and the hyponomic
curve of the growth lines upon the ventral side (fig. 7)
All figures are natural size. The originals are from Roch-
ester (Arey collection).

Leperditia balthica Hisinger, var. guelphica Jones

Page 106

9 The largest valve observed. X2

10, 1 1 Two views of a valve, showing the eye tubercle distinctly.
X2. Both from the Guelph at Rochester

GUELPH FAUNA

Memoir 5 . N . Y. State Museum

Plate 21.

W S.Barkentitvdel. et lith.

J . 3 Lyon CQ. State Printer

GUELPH FAUNA IN THE STATE OF NEW YORK 185

Calymmene niagarensis Hall

Page 107

FIG.

12 Cephalon from the Guelph at Rochester, x2

Proetus sp.

Page 108

13 Cranidium, from a gutta-percha squeeze of a natural impres-

sion. x2. Rochester

14 Another, smaller cranium. X3

15 Small pygidium, retaining partially the test. X2

16 Largest pygidium observed. X2

Originals of fig. 14-16 are from the Upper Shelby bed
(N. Y. State Museum).

INDEX

Page numbers referring to descriptions of fossils are printed in black face type.

Acephala, 119.
Acervularia, 26, 27.
Acleistoceras, 95.
Agassiz, A., cited, 116.
Allen creek section, 17-18.
Ambonychia acutirostra, 48.

acutirostrum, 48.

aphaea, 48.

mytiliformis, 49.
Ammonites, 120.
Amplexus, 124.
Annelida, 105-6.
Anthozoa, 23-36.
Arey, Albert L., acknowledgments to, 3 ;

cited, 8, 77 ; collection of fossils, 8.
Asaphus stokesi, 108.
Astrocerium parasiticum, 29.

pyri forme, 29.

venustum, 29.
Atrypa, 6, 128.

cuneata, 46.

neglecta, 45.

nitida, 44.

reticularis, 21.
Avicula subplana, 49.

triquetra, 6.

undata, 50.

Bactrites, 95.

Bahamas, salt lagoons, 118.

Barrande, cited, 98, 102, 104.

Barre, Guelph dolomites, 17.

Barrois, cited, 59.

Barton beds, 21.

Belemnites, 120.

Bell, Robert, cited, 6; observations, 7.

Bellerophon, 51-54.

leda. 54.

lyra, 54.

(Bucania) perforatus, 54.

shelbiensis, no, 51-54.
explanation of plate, 150.

tuber, 52.

Bellerophontidae, 53, 54.
Bernard, Felix, cited, 119.
Billings, cited, 27, 40, 52, 57, 71, 87, 88,

125-

Bourgeat, Abbe, investigations of, 119.
Boyd, G. W., fossils obtained by, 5.
Brachiopoda, 5, 38-47, 113, 114, 120, 125,

127, 128, 131.
Brighton, exposures, 18.
Bucania, 52, 53.

angustata, 54, 56, 59, 127.

chicagoensis, 57.

devonica, 53.

expansa, 52, 53.

perforata, see Bellerophon (Bucania)
perforatus.

profunda, 53.

stigmosa?, 51.

sulcatina, 52.
Bucaniidae, 53.
Bucanopsis, 54.
Bumastus barriensis, see Illaenus (Bumas-

tus) ? barriensis.

Calvin, Dr Samuel, cited, 128.
Calymene blumenbachii, 107.

var. niagarensis, 107.
Calymmene, 107.

niagarensis, n, 107, 112, 133.

i88

NEW YORK STATE MUSEUM

Calymmene niagarensis — (Continued').
explanation of plate, 185.

cf. niagarensis, 10.
Camarotoechia, 45-46.

indianensis, no.

( ?) indianensis, 46.
explanation of plate, 148.

neglecta, 10, no.

( ?) neglecta, 45-46, 46.

explanation of plate, 148.
Canada, Guelph formation, 4 ; dolomites,

20-22; Stratigraphic relations of forma-
tion in, 125.
Caryocrinus, 124.

ornatus, 124.
Catenipora agglomerata, 34.

escharoides, 33.

labyrinthica, 33.
Cephalopoda, 5, 77-105, 113, 114, 117, 120,

135, 137-
Cerithium, 119.
Chamberlin, T. C, cited, 105, 114, 120,

121, 126.
Cidaridae, 119.
Cladopora, 33, 116.

multipora, 10, 33, 109.
Clarendon, Guelph dolomites, 17.
Clarke, John M., cited, 40, 53, 95, 103, 123,

128, 131.
Clathrodictyon ostiolatum, 38.

(Stromatopora) ostiolatum, 38.
Clathrodictyum, 37-38.

ostiolatum, 37-38, 109, 134.
explanation of plate, 141.
Clinoceras, 95.
Cliona, 116.

Cobleskill limestone, 136-37.
Coelidium, 65-67.

macrospira, 10, n, 16, 21, 65-67, in.
explanation of plate, 154-55, 161.

cf. vitellia, 67, in.

explanation of plate, 155.

Coelocaulis, 4.
Coelocaulus, 67.
Coenostroma constellatum, 37.

galtense, 36, 37.
Conchidium occidentale, 128.
Conocardium, 50.

sp., 50, no.
explanation of plate, 150.

ornatum, 50.
Conus, 117.
Coral reef origin of Guelph dolomites,

1 14-16.
Coral reefs, of Red sea, 117-18. Sec also

Jurassic reefs of France ; Racine reefs in

Wisconsin.

Coralline limestone, 136-37.
Corals, 113, 115, 133, 135.
Corbis, 119.
Cordoceras, 98.
Cornulites, 6, 105-6.

arcuatus, 10, 11, 105-6, 112.
explanation of plate, 146.

flexuosus, 105.
Crania, 109.

sp., 38.

explanation of plate, 146.
Crustaceans, 117.
Cyathophyllum pelagicum, 25.
Cyclonema sulcata, 62, 124.

sulcatum, 62.

Cypricardites ? quadrilatera, 132.
Cyrtoceras, 94, 95.

amplicorne, 98.

(Phragmoceras) amplicorne, 98.

arcticameratum, 87, in, 127.
explanation of plate, 172, 174.

bovinum, 90, 98, in.
explanation of plate, 174, 178.

brevicorne, 89, 127.

cf. brevicorne, 89, in.
explanation of plate, 169.

cancellatum, 91.

INDEX TO GUELPH FAUNA IN NEW YORK

189

Cyrtoceras clitus, 96.

dardanus, 91.

fosteri, 91.

Hercules, 98.

herzeri, 132.

myrice, 84, 85, 132.

erodes, 10, 88-89, in.

explanation of plate, 172-73.

reversum, 96, 97.

rex, 98.

? subcancellatum, 16.

tyrannus, 98.
Cyrtorhizoceras, 90-92.

curvicameratum, 90-92, in.
explanation of plate, 176-77.

minnesotense, 92.
Cystostylus infundibulus, 35.

Ball, cited, 118.
Dalmanella, 41-42.

elegantula, 10.

cf. elegantula, 41-42, no.
explanation of plate, 147.

cf. hybrida, 42, no.

explanation of plate, 147.
Dalmanites, 108.

sp., 10, 108, 112.

limulurus, 108.

verrucosus, 108.
Davidson, cited, 40, 41.
Dawson, Sir William, cited, 37.
Dawsonoceras, 81-83.

annulatum, 21, 82, 83, 85.

var. americamim, 81-83, in.

explanation of plate, 161, 164.
De Koninck, cited, 26, 52, 53.
Delthyris, 6.
Diaphorostoma, 59.

niagarense, n, 59, no.

explanation of plate, 161.
Diceras, 119, 120.
Dinobolus conradi, 127, 128.

Diphyphyllum, 25.
Diplophyllum, 25-28.

caespitosum, 25-28, 109.
Doelter, cited, 115.
Dybowski, cited, 26.

Eccyliomphalus, 76.
Echini, 119, 120.
Echinoderms, 117.
Edwards, cited, 26, 32.
Enterolasma, 24-25.
caliculus, 10, 15, 19, 20, 21, 24, 37.
cf. caliculus, 24-25, 109.

explanation of plate, 140.
radicans, 24.
waynense, 24.
Eotomaria, 68-71.
areyi, 68-70, no.

explanation of plate, 156.
durhamensis, 68, no.

explanation of plate, 161.
galtensis, 11, 70-71, no.

explanation of plate, 161.
halei, see Pleurotomaria (Eotomaria)

halei.
kayseri, 70, no.

explanation of plate, 154, 156.
laphami, see Pleurotomaria (Eotomaria)

laphami.

Eridophyllum, 25, 26.
simcoense, 27.
verneuilianum, 27.
Eunema fatua, see Trochonema (Eunema)

fatua.

Euomphalus, 5, 61, 75-76.
fairchildi, 75-76, in.

explanation of plate, 156.
gothlandicus, 76.
macrolineatus, 62.
sulcatus, 6.
Explanation of plates, 139-85-

i go

NEW YORK STATE MUSEUM

Fasciolaria, 117.

Favosites, 15, 16, 18, 19, 28-32, 116, 124.

basaltica, 31.

basalticus, 32.

favosa?, 30.

favosus, 30, 130.

forbesi, 31-32, 109.

gothlandica, 28, 30.

gothlandicus, 30-31, 109.

hisingeri, 29-30, 109.

? multipora, 33.

niagarensis, 28-29, 109, 132.

venusta, 30.

venustus, 30.
Fischer, cited, 53.
Foerste, cited, 49, 130.
Foord, cited, 95.
Freeh, cited, 26, 32.

Gait beds, 6, 123.

Gait limestone, term, 6.

Gastropoda, 4, 51-76, 113, 114, 117, 119,

122, 128, 133, 135, 137.
Gebhard, John, cited, 136.
Goldfuss, cited, 34.
Gomphoceras ? sp., 16.

septoris, 137.

Goniophora crassa, 114, 117.
Grabau, A. W., cited, 16, 43.
Grant, C. C., acknowledgments to, 3 ; cited,

20.
Guelph dolomites, coral reef origin, 114-

16; lower beds, 10; upper beds, n, 15.
Guelph fauna, historical, 5-9 ; conditions of

life and sedimentation during the preva-
lence of, 114-21; distribution of, 122-

37-
Guelph sea, outcome of a shrinking of the

Niagaran sea, 117.
Gyroceras, 92.

abruptus, 92.

americanum, 92.

Gyroceras bannisteri, 93.
farcimen, 92, in.

explanation of plate, 178.

Haime, cited, 26, 29, 31, 32.

Hall, James, cited, 6, 7, 16, 20, 25, 29, 33,

34, 40, 42, 43, 45, 49. 52> 53. 56, 57. 59.

62, 65, 67, 71, 79, 83, 86, 87, 93, 101, 102,

104, 122, 123, 124, 125, 126, 128, 129,

131, 136.
Halysites, 16, 18, 33-35, 115.

agglomerata, 34.

agglomeratus, 34-35, 109.

catenularia, 33.

catenularius, 10, 33-34, 35, 109.

catenulatus, 33, 130.
Hamilton, section at, 20-22.
Hancock, cited, 116.
Hartnagel, C. A., cited, 136-37.
Heliophyllum, 28.

sp. indct., 28, 109.

explanation of plate, 140.
Hoernes, cited, 115.
Holopea, 74.

guelphensis, 127.

harmonia, 127.
Homoeospira, 128.
Horiostoma, 59, 60, 135.

konincki, 60.

lineatum, 62.
Hormotoma, 67, 72-74.

whiteavesi, 72-74, in.

explanation of plate, 157.
Hyatt, A., cited, 82, 89, 95, 98, 101, 102,

105.
Hydrozoa, 36-38.

Hionia canadensis, 137.

galtensis, 137.

Illaenus (Bumastus) Pbarriensis, 124.
Illinois, occurrence of Guelph in, 129.
Indiana, Guelph beds in, 130-31.

INDEX TO GUELPH FAUNA IN NEW YORK

Iowa, Niagaran in, 128-29.
Isis, 115.

Jones, T. R., cited, 106.
Jurassic reefs of France, 119.

Kayser, E., cited, 136.
Kindle, E. M., cited, 130.
Kionoceras, 82, 84-86.

darwini, 84-86, in, 137.

explanation of plate, 162, 165-67.

medullare, 86.

explanation of plate, 162.

cf. medullare, in.
Klunzinger, cited, 116.
Koken, E., cited, 52, 53, 58, 60.

Lambe, L., cited, 25, 27, 29, 31, 32, 33, 34,

35-
Lamellibranchiata, 47-51, 113, 114, 117,

135-

Le Claire limestone, 122, 128.
Leperditia, 106-7.

sp., 107, 112.

balthica, far. guelphica, 106-7, 112.
explanation of plate, 184.

fonticola, 106.

phaseolus var. guelphica, 106, 107.

scalar is, 107.
Leptaena, 42.

depressa, 42.

rhomboidalis, 10, 11, 21, 42, no.
Lichenalia concentrica, 10.
Lima, 119.

Lindstrom, G., cited, 53, 58, 59, 74, 76.
Lithostrotion, 26.
Lockport dolomites, 7.
Lockport limestone, 10.
Logan, Sir William, cited, 6, 125 ; observa-
tions, 7.
Lonsdaleia, 27.
Lophospira, 71-72.

Lophospira bispiralis, 10, 71-72, in.

explanation of plate, 160.
Loxonema, 74, 119, 135.

boydi, 6, 127.

longispira, 125.

magnum, 73.
Loxoplocus, 5.

solutus, 1 1 8.
Luther, D. Dana, acknowledgments to, 3 ;

analysis of section in Niagara county, 14.

McChesney, cited, 57, 78, 83, 86, 101, 102.
McCoy, cited, 57.
Macrochilina, 74.

sp. indet., 74, in.

explanation of plate, 161.
Madrepora, 115.

muricata, 115.
Meek, cited, 86.
Megalomus, 5, 114, 117, 118, 133, 135.

canadensis, 48, 113, 127, 132, 133.
Michigan, Guelph fauna, 131.
Miller, S. A., cited, 63.
Milne- Edwards, cited, 29, 31.
Mitroceras, 102.
Modiolopsis, 50-51.

sp. cf. Modiolopsis subalata? 50-51, no.
explanation of plate, 149.

subalatus?, 50.
Monomerella, 5, 39-41, 114, 117, 123, 125,

135-

durhamensis, 41.
egani, 128.
greeni, 128.
kingi, 41.
newberryi, 131.
noveboracum, 10, 39-41, 109, 113.

explanation of plate, 142-43, 144-45,

148.

cf. orbicularis, 128.
ortoni, 131.
prisca, 40, 41, 127, 131.

ig2

NEW YORK STATE MUSEUM

Monomerella walmstedti, 41.
Monroe county, dolomites, 9, 17-20.
Munier-Chalmas, cited, 59.
Murchisonia, 5, 74, 118, 119, 125, 135.

billingsana, 127.

hercyna, 127.

hespelerensis, 72.

laphami, 133.

loganii, 65, 67, 124, 127.

longispira, 127.

macrospira, 65, 66, 127, 132, 133.

mylitta, 125, 127.

terebralis, 137.

vitellia, 67.
Murie, cited, 38.
Murray, observations, 7.
Myalina mytiliformis, 49.
Mytilarca, 47-49.

acutirostrum, 48-49, no.
explanation of plate, 150.

eduliformis, 47, no.

explanation of plate, 150

foerstei, 49.

mytiliformis, 49.
Mytilus edulis, 47.

sigillum, 47.

Natica, 119.

Nerinea, 119, 120.

Newberry, cited, 132.

Niagara county, limestone and dolomite,

13-16.

Niagara dolomite, 7.
Nicholson, cited, 31, 32, 34, 37, 38, 40.
Niosch, investigations of, 119.
Norton, W. H., cited, 129.
Nucleospira, 128.

Obolus conradi, 132, 133.
Oehlert, cited, 59, 67.
Ohio, Guelph fossils in, 131-34.
Oncoceras, 94, 95.

Ontario, dolomites, 4, 20-22.
Oppel, investigations of, 119.
Oriostoma, 59.

Orleans county, dolomites, 9-11, 17.
Orthis elegantula, 41.

hybrida, 42.
Orthoceras, 77-81.

abnorme, 133.

angulatum, 78, 85.

annulatum, 83.
var. americanum, 81, 82.

bartonense, 21, 83.

cadmus, 82, 86.

cancellatum, 86.

colnmnare, 78.

crebescens, 78, 79, 80-81, in.
explanation of plate, 162, 164.

darwini, 84, 85.

laeve, 6.

laphami, 82.

medullare, 82, 86.

nodocostatum, 82, 83.

rectum, 78-79, in.

explanation of plate, 167.

scammoni, 77, 78.

selwyni, 77, 78.

trusitum, 11, 77-78, in, 137.
explanation of plate, 162, 168.

undulatum, 82.

virgatum, 82.

virgatum ( ?), 86.
Orthothetes subplanus, 10, 21.
Orton, Edward, cited, 132, 133, 134.
Ostracoda, 106-7.

Pecten, 119.
Peismoceras, 105.
Pentamerus, 117.

mysius var. crassicosta, 130.

oblongus, 123, 125, 133.

occidentalis, 114, 122, 123, 124, 128, 131,
132.

INDEX TO GUELPH FAUNA IN NEW YORK

193

Petraia waynensis, 24.
Phragmoceras, 5, 98, 99-100.

amplicorne, see Cyrtoceras (Phragmo-
ceras) amplicorne.

byronensis, 98.

nestor, 98.

parvum, 99-100, in, 132.

explanation of plate, 184.
Phragmoceratidae, 98.
Plates, explanation of, 139-85.
Platystoma niagarense, 133.

niagarensis, 59.
Plectoceratidae, 101.
Pleurotomaria, 5, 119, 135.

bispiralis, 71.

durhamensis, 68, 72.

galtensis, 68, 69, 70.

halei, 63.

(Eotomaria) laphami, 70.

huronensis, 125.

(Eotomaria) laphami, 70.

pauper, see Trochonema (Pleurotoma-
ria) pauper.

perlata, 21.

solarioides, 132.

solarioides ?, 125.

subdepressa, 137.
Poleumita?, 127.
Poleumita, 59-35, 119.

crenulata, 10, 64-65, 110, 113, 137.
explanation of plate, 159.

scamnata, n, 15, 60-62, 63, 64, lio.
explanation of plate, 158.

sulcata, n, no.

? sulcata, 62-63.

explanation of plate, 160.
Polydilasma turbinata, see Zaphrentis

(Polydilasma) turbinata.
Polytropis, 5, 60.

crenulatus, 64.

macrolineatus, 61.

sulcatus, 62.

Pompeckj, cited, 89, 96.
Poterioceras, 93-97.
sp., 97, ill.

explanation of plate, 169.
sauridens, 10, 40, 93-97, in.

explanation of plate, 170-171.
Price, I. A., cited, 130.
Proetus, 108.
sp., 10, 11, 108, 112.

explanation of plate, 185.
corycaeus, 108.
stokesi, 1 08.

Protophragmoceras, 97-98.
murchisoni, 98.
patronus, 10, 97-98, in.

explanation of plate, 180.
Pterinea, 49-50.
subplana, n, 16, 49, no.

explanation of plate, 149.
undata, n, 50, no.

explanation of plate, 149.
Pycnomphalus, 4-5, 135.
Pycnostylus guelphensis, 134.

Racine limestone, 124, 126.
Racine reefs in Wisconsin, 120-21.
Red sea, life inhabiting reefs of, 117-18.
Rhinobolus, 5, 114, 117.

davidsoni, 128.
Rhynchonella, 128.

indianensis, 46.

neglecta, 45.

pisa, 46.
Rhynchotreta, 46-47, 128.

cuneata americana, 10, 48-47, no.

explanation of plate, 147.
Ricinula, 117.

Rochester and vicinity, exposures, 19.
Roemer, F., cited, 53.
Rominger, C, cited, 25, 26, 36, 131.

Salpingostoma, 53, 56.
macrostoma, 56.

194

NEW YORK STATE MUSEUM

Salter, cited, 74.

Sandberger, cited, 60.

Schuchert, C, cited, 128.

Shelby dolomites, 9-11, 12, 13.

Simpson, G. B., cited, 24.

Sowerby, cited, 57.

Spencer, J. W., cited, 20, 3^ 83, 96.

Sphyradoceras, 100-5.

Spirifer, 42-44, 122, 128.

sp., 44.

bicostatus, 43, 44.

cf. bicostatus, explanation of plate, 147.

crispus, 10, u, 16, 42-44.
explanation of plate, 147.
var., no.
var. corallinensis, 43, 137.

eriensis, 43.

niagarensis, 124.

plicatellus, 44.
var. radiatus, 44.

radiatus, 124.

sulcatus, 124.
Spirigera, 122.
Spyroceras, 102.

bilineatum, 82, 103.
Straparollus, 76.

crenulatus, 64.

daphne, 76.

hippolyta, 76.

mopsus, 76.

niagarensis, 76, 132.

solarioides, 127.
Streptelasma calicula, 24.

radicans, 24.

strictum, 24.

Stricklandinia multilirata, 128.
Stromatopora, 15, 16, 18, 19, 36-37, 115,
"6, 135.

constellata, 36.

galtensis, n, 36-37, 109.
explanation of plate, 141.

Stromatopora cf. Stromatopora constellata,
36-

ostiolata, 37.

ostiolatum, see Clathrodictyon (Stroma-
topora) ostiolatum.

typica, 37.
Stromatoporoids, 5.
Strombodes pentagomis, 130.
Stropheodonta profunda, 10, 18.
Strophomena rugosa, 124.
Subulites, 119.

ventricosa, 125.
Synoptic list of Guelph fossils of New

York, 109-12.
Syringopora, 35-36, 116.

infundibula, 35.

infundibulum, 35-36, 109.
explanation of plate, 140.

multicaulus, 36.

verticillata, 35.
Systrophoceras, 105.

Tabulata, 28-36.
Tetracoralla, 23-28.
Thoracoceras, 82.
Tremanotis alpheus, 54.
Tremanotus, 56.

alpheus, 132.

angustatus, 54.

dilatatus, 57.
Trematonotus, 53, 54-59, 135.

alpheus, 10, n, 20, 40, 54-59, no, 113,

127, 132.
explanation of plate, 151, 152-53.

chicagoensis, 58.

longitudinalis, 58.

trigonostoma, 58.
Trematospira, 16, 128.
Trigonia, 119.
Trilobita, 107-8, 114.
Trimerella, 4, 5, 114, 117, 123, 125, 133,

135-

INDEX TO GUELPH FAUNA IN NEW YORK

195

Trimerella acuminata, 131.

grandis, 127, 131, 133.

ohioensis, 131, 132, 133.
Trimerellidae, 41, 114, 128.
Trochoceras, 5, 1 00-5.

aeneas, 102, 104.

asperum, 104.

costatum, 10, 103-5, in.
explanation of plate, 182.

desplainense, 10, n, 100-3, 104, 105,

in, 127, 133.
explanation of plate, 182-83.

desplainensis, 100.

gebhardi, 102.

optatum, 1 02.

sandbergeri, 104.

waldronense, 21.
Trochonema, 75, 127.

(Eunema) fatua, 75.

cf. fatuum, n, 75, no.
explanation of plate, 160.

pauper, 132.

(Pleurotomaria) pauper, 62.
Trochus, 117, 135.
Tubipora catenularia, 33.
Turbinella, 117.
Turbo, 119.

Hindi, cited, 49, 52, 53, 56, 67, 68, 76.
Von Baer, cited, 117.

Waagen, cited, 52, 53.

Walther, cited, 115.

Wayne county, Guelph fauna, 5 ; locality

for " Onondaga salt group " fossils lost,

7; dolomites, 20.
Weller, Stuart, cited, 129.
Whiteaves, cited, 4, 23, 29, 31, 34, 35, 40,

4i, 45. 50, 51, 52> 57. 60. 61, 62, 63, 64,

66, 68, 71, 73, 74, 77, 83, 85, 86, 87, 88,

89, 102, 105, 107, 113, 134.
Whitfield, R. P., cited, 33, 34, 35, 48, 57,

62, 74, 79, 83, 107, 126, 127, 131.
Whitfieldella, 44-45.

hyale, 45, 127.

nitida, 44-45, no.

explanation of plate, 148.

oblata, 10.

nucleolata, 45.

Wisconsin, relations of Guelph of, 126-28.
Worthen, A. H., cited, 78, 79, 86, 123, 129.

Zaphrentis, 23-24.

bilateralis, 10, 19.

racinensis, 23.

cf. racinensis, 23-24, 109.
explanation of plate, 140.

turbinata, 24.

(Polydilasma) turbinata, 23.
Zittel-Eastman, cited, 105.

14 DAY USE

RETURN TO DESK FROM WHICH BORROWED

EARTH SCIENCES LIBRARY

This book is due on me Tkstoate stamped below,

on the date to which renewed.
Renewed books are subject to immediate recall.

or

LD21-40m-2,'69
(J6057slO)476 — A-32

General Library

University of California

Berkeley

• - . • - ••:-•

- .

m m : :

:*.n" •>/.;. -^r:::

- .- • - - T*t • • ', ',.•.-...,:

- .;:-S^

, .