John Almon.

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matter, had eacaped the attention of the writer in preparing a clasaifieation of the
Aviculida, or tne name P$eudomonoti» would have been adopted. In the same
note Prof. Beyrich proposed another genus OasHanella, with the Avicfda gryphot-
<Ua of Miinster as ita type. For this, the writer, on the same grounds, propoeed
the name Qrypkorhynchiu, in 1864. Bey rich's names for both of these geoara, how-
ever, having priority of date, will liave to talce precedence. Although neither of
these genera would be admitted by those who give such wide limits to groups, it is
manifest that such distinctions are attracting the attention of systematic workers
everywhere. For instance, Laube adopts Cataianella as a good genus in his beantiliil
Monograph of the 8t Cassian fossils recently published. He also there proposes,
on apparently good characters, a genus Horneuia, for a group of which the so-
called Germl/ia aociaiu of authors is the type; though it is probable this will
prove to be a synonym of Mr. Gabb's genus RhynchortteriUy published in the Galifor-
nia Report in 1864, and founded upon a shell presenting similar external characters*
and from near the same horizon, in Nevada.

1 For this type the writer proposed the name Avieulopiima, in 1864, (this Jour.,
TsL xzzvii, cited above.



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Eeview of GeinUz on the rocks and fossils of Nebraska. 175

The propriety of referring the little Permian and Carbonife-
rous shells for which Prof. Jewing proposed the name Bakevellia^
to the genus Qervilka^ is, to say the least, very doubtful. Al-
though these types are unquestionably closely related, the uni-
form smaller size of the species of the former group, the more
nearly equal convexity of their valves, usually smaller number
of cartilage cavities, and generally less elongated form in pro-
portion to the length of the hinge line, are characters which,
when viewed collectively, indicate generic diflferences. The
most important distinction, however, is found in the hinge teeth,
which although variable in both groups, differ in that those on
the posterior side of Bakevellia are elongate, linear and directed
parsJlel to the hinge line, instead of being shorter and oblique ;
while those in front of the beaks range obliquely forward and
downward, instead of forward and upward, as in Gei-mUea. Again
Bakevellia has the anterior muscular scar proportionally larger,
so much so indeed that Prof. King referred the genus to the
ZHmyariOj though it belongs to the Avicula group near Gervillta.

Again, in including in the genus Pecten the Paleozoic shells
for which Prof. McCoy proposed the name Aviculopecten, Prof.
Geinitz ignores important distinctions that have been known for
fifteen or sixteen years past, to clearly separate these grou{>s.
These are the proportionally larger size of the posterior ear in
Avtcuhpeeten, instead of the reverse, and its broad Pterinea-like
cardinal area, or hinge plate, with parallel longitudinal cartilage
furrows, and in general without traces of a central cartilage pit
under the beaks. Even Woodward, who was the most ex-
tremely conservative of all modern conchologists, in regard to
generic distinctions, not only separated these snells from the ge-
nus Pecten, but even placed them doubtfully in the family Amc-
viidx. No well informed conchologist would at the present
time refer to the genus Pecten, as properly restricted, any Paleo-
zoic species.*

He is also behind the present state of conchological science
in placing in the genus Area forms like the so-called A, striata
Schlot. (sp.), with the posterior hinge teeth linear, elongated
and ranging parallel to the cardinal margin. These belong to
the genus macrodon of Morris and Lycett. Even Woodward
separates this group from Area, but without sufficient reason in-
cludes it as a subgenus under Ouctdlcea. There are no true Ar-
eas in the Paleozoic rocks.

Another unnatural mingling of distinct types is his reference
of typical Ledas (properly Nuculana,) to the genus Nucula.

* Proil Agassix, who has gone over the whole fiunily Fectenida with great care,
and hta usual thoroni^hness, does not, if correctlj uoderatood by the writer, refer
any of the fossil snecies from older rocks than the Tertiary, to the genus Preterit as
properly restrictea.



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176 Review of (Seiniiz on the rocks and/ossib of Nebraekeu

Woodward, Carpenter, Oraj, H. & A. Adams, Deshayes, Chenu,
in short, all good oonchologists admit this as a distinct genus
from Nxtcula; while Carpenter, H. k A. Adams, M5rch, and other
late systematic writers, separate it as the type of a distinct /ziit%
from the NucuUda.

Bat the most unaoooantable error into which Prof. Geinitz
has fitllen, is in placing in the genus KhynchoneUa^ Spirtfer hemi-
plicatus of Hall, the type of the new genus Synlrilasma^ Meek
k Worthen (111. Geo! Report, ii, 321). Being a somewhat
peculiar shell, if the cardinal region of the valves was hidden
in the matrix, and the surface strise somewhat obscured, it might
be mistaken for a RhynchoneUa ; but the most surprising thing
is that he should have referred it to that genus, wnen.the very
specimens figured by him show it to have a straight hinge line,
and a well defined cardinal area,* divided in the ventral valve
by a triangular open fissure, while another figure shows it to
have in the dorsal valve, the crura and cardinal process^ as in
Orthis. The fact is, this shell does not even belong to the Rhyn-
chonellidaSf as its punctate structure and other characters show.
The fact that Prof Geinitz, after referring it to RhynchoneUa^
speaks of it as '' this rare and beautiful Tmbratula^^^ would also
seem to indicate that he does not even re^rd the distinctions
between these two genera (well known to be the types of two
distinct families), of much oonseq^uence.

Again Prof. Geinitz overlooks important distinguishing char-
acters, when he refers (without even a recognition as a sub-
genus) to the genus OrUtie^ a typical Streptorhynchus (properly
nemiproniUs). The distinctions between these types are well
defined, so much so that even Mr. Davidson, who is always cau-
tious and conservative in admitting even subgenera, considers
it a good subgenus; while most of the highest authorities in
various departments of recent zoology view differences of do
greater importance as being of full generic value.

Any of the numerous collectors of western Coal-measure fos-
sils will at once recognize the spines figured by Prof Geinitz
(pi. iv, fig. 29), and referred by him to Aciinoerinus^ as those of
^eacrimis mucrospinus McChesney. These apines, probably be-
longing to two or more allied species, are widely distributed in
our Coal-measures, from West Virginia and Pennsylvania, to

* It it flcaroelj neoemary to explain here that when Pro£ de Kooinck speaks of
ao area, in describing Rhynehonula angulata Linn (to which species Prof. Qeinits
refers the shell under consideration), he alludes to a flattened oral space on each
side of the shell, converging to the beaks at an angle of about ninetj degrees, and
not to a true cardinal area, such as that term is applied to in describmg Brachiopods
gemuidlT. If any one, howcTer, has anj doubts on this point, these will at once be
removedf by turning to Mr. Davidson's excellent figures and description of R, amgu-
laUi (Mooogr. Brit. Garb. Biach., p. xix), prepared after a carefol study of lAoomrn'm
original specimen.



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Review of Geinitz on the rocks and fossils of Nebraska. 177

Nebraska, and southward to Texas and New Mexico; while
thej may be at a glance distinguished from those of any of the
forms usually referred to Aciinocrinus. They belong indeed to
different parts of the crinoid, being modified second radial pieces,
while those of A. cornigerotcs, and A. Oouldi^ with which Prof.
Geinitz compares them, are modified vault-pieces, that rise ob-
liquely upward out of the vault from above the horizon of the
arms. This difference in the position and relations to the other
parts, of these spines, imparts an entirely different form to the
head or larger extremity, from those of any of the Sub-carbon-
iferous crinoids, that renders it very easy to distinguish them.
It is unnecessary to inform any one acquainted with western fos-
sils, that no species of Actinocrinus^ even giving that genus its
widest limits, has yet been found above the horizon of the St.
Louis Limestone, of the Sub-carboniferous series, and the only
two species found thus far up belong to the Batocrinus section.

Having thus pointed out what are believed to be errors in re-
gard to cenerio references, respecting which students who may
use Prot Geinitz's work ought to bs informed, some remarks
on the specific relations of these fossils may not be out of place.

First a little planorbicular shell (fig. 6, pi. 1), referred by Prof.
Geinitz to Serpula {Spirorbis) planorUtes Munster, is certainly, as
he suspected, the same figured and described by Prof. Hall from
the Coal-measures of Illinois under the name Euomphalus rugo-
SU8, in the Iowa Eeport. The reasons, however, for not believ-
ing it to belong even to the same primary division of the Animal
Kmgdom as the genus Sfirorbis^ have already been stated.
That it is also clearly distinct specifically from the European
& planorbiteSj even if they could oe forced into the same genus,
is more positively certain, as I know from a direct comparison
with autfientic foreign specimens of the latter.* Of the Nebras-
ka shell I have numerous specimens before me, from various lo-
calities in that region, as well as from Kansas, western Iowa and
from Illinois. On comparing these with German examples of
S. spirorbitesy they are easily distinguished by having the whorls
always very distinctly quadrangular, and broadly flattened on the
outer side, instead of presenting an oval section with a rounded
or subangular dorsal side as in the German species. The latter
also has its deepest umbilical concavity on the left side (placing
the shell with the mouth turned downward and away from the
observer), instead of the reverse. Prof. Geinitz had also ob-
served that there is a shallow furrow around the middle of the
side of the whorls in the Nebraska fossil, where there ought to
be a prominence to make it correspond to the S, spirorbiiesj but
thinks this is due to the accidental pressing inward of this prom-

* All the foreign specimens of Permian fossils alluded to in tlie paper belong to
the Museum of the Smithsonian Institution.



Am. Jour. Scl—Sbcond Sbbiks, Vou XLIV, No. 181.— Sept., 1867.
23

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176 Review of Geinilz t>n the rocks and fossils of Nebraska.

inence. This obscure farroW| however, is a natural character in
the E. rugosuSf though not always equally well defined, and some-
times becoming obsolete. Finally it attains a size of from four
to six times wat of the spirorbUes. The latter, as shown by
Prof. Geinitz's figures in his ''Dyas," as well as by the specimens,
varies considerably in some respects, but the American shell is
very constant and regular in form, and in most of its characters.

I diflfer, if possible, still more decidedly firom Prof. Geinitz, in
thinking Spirorbis lielix of King identical with this; and doubt
the identity of King's species with the true S. spirorbites. If our
shell is identical with any European species, it agrees most nearly
with the Carboniferous species EuompJialus carbonarius Sowerby
(=i?. quadratus McCoy, Carb. Foss. Ixelaud, pi. 5, fig. 22), which
it quite nearly resembles, though even these forms are clearly
distinct.

Murchisonia svhtceniata Geinitz, Carb. und Dyas, pi. 1, fig. 18.
As already stated this is a true Orihonema^ and will have to take
the name 0. mbUmiiaUi. •

BelleropJion interlineatus Portlock. Geinitz, ib. This may or
may not be identical with Portlock's species. At any rate it
occurs in the Coal-measures of Kansas. The B. carbonarius^
and B. Montfortianus N. k P. mentioned by Prof. Gteinitz among
other fossils from the beds he refers to the Dyas, are well-known
Coal-measure species in the West His B. Marcouanus seems to
be a good new species.

MacrocheUus Hallianus Geinitz, ib., fig. 7. This probably be-
longs to the genus Soleniscus Meek k W orthen (Ilhnois Report^
ii, pi. 81, fig. 15), as it presents much the appearance of speci-
mens of the type of that genus with the beak and lower part of
the outer lip broken awav. If the specimen firared has had an
accidental depression made on the columella above the fold, it
may even be the typical species originally described fix>m the
Coal-measures of Illinois.

AUorisma elegans King. Geinitz, ib., £ 21. K we may judge
from the published figures and descriptions of this species, there
can be little room for doubting that the Nebraska shell figured
under that name is a distinct species, even after making liberal
allowances for variations. If so, it may be called AUorisma f
Geinitzi^ though it seems very doubtful whether it is a true At-
lortsma. It appears to be congeneric with, and allied specifically
to, species described by Dr. Snumard from the Coal-measures of
Kansas and Missouri, under the names Leptodomus Topekaensis^
and L. granoaus. It is probable that all these shells should be
referred to the genus Sedgwickia of McCoy, as properly restricted
to the types for which that name was first proposed (see Paleont.
Upp. Missouri, p. 38).

JSoIenomya biarmica deVern. Geinitz, ib. The specimen figured



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Review of Creinilz on the rocks and fossils of Nebraska. 179

is too imperfect for satisfactory identification or to show any re-
liable characters for distinguishing it from forms in our Coal-
measures.

Asiarte gUthoea McCoy. Geinitz, ib., fig. 28. This agrees quite
nearly with McCoy's figure, but to establish positive specific iden-
tity would require a comparison of specimens showing the hinge
and interior, which might even show them to belong to difierent
genera. They are probably both Edmondias, however, and look
unlike Astarie. Dr. White finds them in the Upper Coal-meas^
ures of Iowa.

Astarie NArascensis (n. sp.), and A. Morionensis Geinitz, ib., as
well as the form he figures A. Vallisnerianus King, have more
the aspect of Astarte; but the latter looks less like Prof. King's
figures than the form figured as a new species A. Nebrascensis.
At any rate, specific identifications, and even generic references
of such shells, can be admitted only provisionally, until the
hinge and interior is known.

Schizodus obscurus Sowerby, and S, Rossicus de Vern. The
forms figured under these names on plate I, resemble these Eu-
ropean snells quite nearly ; but it must be obvious that in a genus
like this, in which species vary more or less in outline, ana pre-
sent so few characters for identification, little reliance can be
placed upon identifications from external characters only, espe-
cially when the specimens were obtained at so widely distant
localities. The form referred to & (Aseurus (figs. 30 and 81), looks
more like Prof. King's figures of S. Schlotheimi Geinitz, as well as
more like natural casts of that species now before me from Ger-
many, than like Sowerby 's or King's figures of S. ohscurus, which
shows more elevated, and more ventricose beaks. From a tracing
of the type of Prof. Swallow's Oyprvcardiat Wheeleri^ described
from the Missouri Coal-measures, it appears almost certain that
it is the same here figured under the name of S, obscurus. Young
examples of S. alpina (=:Dolabra f alpina Hall, Iowa Bep., pi. 29,
f. 2) irom the Lower Coal-measures, in some of its variations,
rather nearly resemble the form referred by Prof. Geinitz to R
Bossicus, though that is doubtless a distinct species. Dr. White
finds both of the shells figured by Prof. Geinitz near the middle
of the Upper Coal-measures of Iowa.

Area striata Schlot. Geinitz, ib,, fig. 82. As already explained,
the shell figured by Prof. Geinitz under this name is a true
Macrodmt. It is the same species described by Mr. Worthen and
the writer (Proceed. Chicago Acad. Sci., i, p. 17) from the Coal-
roeasures at Springfield, Illinois, under the name M, tenuistriata.
It differs clearly from the European M. striata^ however, of which
I have good examples at hand for comparison, in having its radi-
ating lines very much smaller, or reduced to minute obsolescent
strige on the middle and anterior half of the valves. The speci-



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180 Review of Geiniiz on the rocks and fossils of Nebraska.

men figured bj Prof. Geiniiz only retains the shell at the postenor
end, where the stri» are stronger, and agree more nearly with
those of the European form. Through the politeness of Dr.
White, I have had an opportunity to compare good gutta-percha
casts of the hinge of this shell, from the same horizon in western
Iowa as the Nebraska City beds, and they agree well with the
Illinois shell. I am aware that Af. striata varies in the size of
its striae, but it never has them reduced to werj minute or ohso-
lete lines on the anterior part of the valves, like the American
species, which is quite constant in this character. I agree with
Prof. King and others in believing some of the European forms
Prof. Geinitz thinks identical with the species striata, are specif-
ioally distinct

Nucula Kazanensis de Yern. Geinitz, ib., f. 38-34. The fig-
ures of the species Kazanensis, originally published in the Ge-
ology of Russia, being merely from imperfect moulds left in the
matrix, do not afibrd a reliable means for comparison, though
they look like the Nebraska shell. Whatever may be its rela-
tions, however, to the Kazanensis, it will be readily recognized
bj those familiar with the western Coal-measure fossils, as the
form described by Dr. Stevens from the C!oal-measures of Illinois
under the name Leda bellistriata. Of course it is not a Nuculau

Nucula Beyrichi Schloth. Geinitz, ib., 36 and 87. This has
the form of a true Nvcvda^ and agrees pretty well in form with
Prof. Geinitz's figures of German examples of that species given
in Prof. Geinitz's *' Dyas," but less nearly with specimens sent
from Germany under that name. They are probably the same
described by McChesney from the Coal-measures under the name
N. parva.

CUdophorus Pattasi M. Y. & K.* Geinitz, ib., pi. n, fig. 8, (fig.
4 appears to represent some other shell.) This figure was evi-
dently made from the internal cast of a shell very near, if not
identical with, Pleurophorus occidentalis Meek & Hayden, to which
genus at least it certainly belongs. It niay, or may not be, iden-
tical with some of the German shells referred to the Rusoan
species PaUasi; but if we are to be guided in regard to the true
enaracters of the type of that species by the figures and descrip*
tion published by its founders in the Greology of Bussia, the
IfTebraska shell, which is shown to have the posterior hinge-teeth
at least of PlmrophorTis^ must be a very different type, since the
Russian spedes is both figured and described as being ^^com-
pleUly edentuhusy The Russian species is therefore not a jPini*
rophorus (= OUdophorus) at idl, but is more probably, as suggested



* If Ptevmphonf and €t%dojAoru» are tynonyms, or only sectioiM of the i
genot, it it Pleunpkanu and oot CttdophtmUy at Prof. Q«inits wenM to think, that
muit take precedeaoe, as Sang proposed the former geoiis, naming the fo-oalkd
Area eo9tala, ae its .type, in 1844, while CUdophorui was not paWshad br Prot
HaUnntill847.



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Review of Greinitz on the rocks and fossils of Nebraska. 161

by Prof. King, a Oardiomorpha. It also dijffers from the "Nebraska
shell in having the internal ridge bounding the anterior muscular
scar (as shown in the figures and mentioned in the description)
ranging obliquely backward and downward at an angle of 45^
to the axis of the valves, instead of nearly at right angles to the
same, as shown in the figure of the Nebraska species.

I have now before me an internal cast, and a specimen show-
ing the exterior, of what are strongly suspected to be two very
distinct types, that came from Germany with the name Clidopho"
ru6 Pallasi attached. The one showing the exterior agrees quite
well with some of Prof. King's figures of his Oardiomorpha rnodio-
liformis^ which Prof. Geinitz cites As a synonym of the Russian
species Pallasi; but the other specimen, that is, the internal cast,
snows that it, at least, is a true Pleurophorus, as it has a hinge
with teeth like the Nebraska shell ; while one of Prof. King's
figures of a cast and his description show that his modioliformis
is edentulous, like the species Pallasi.

From these facts, it seems highl v probable that two types are^
at any rate sometimes, confounded in Germany, under the name
0. Pallasi;* that is, one edentulous, agreeing perhaps specifi-
cally with Prof. King's modioliformis^ and another with a toothed
hinge, or in other words a true Pleurophorus. If the Nebraska
shell belongs to any European species, it is far more probable
that it is identical with Pleurophorus cosiatus, with casts of which,
now before me from Europe, Prof. Geinitz's figure closely agrees.

CUdophorus {Pleurophorus) ocddentalis M. & H. Geinitz, ib., tab.
ii, fig. 6. The shell figured under this name is certainly not the
P. oecideniaUs Meek & Hayden. In that species, the beaks are,
as described, narrow and projecting beyond the termination of
the hinge, being in fact nearly or quite terminal, while its dorsal
outline is straight or even a little concave from the beaks poste-
riorly. The form figured by Prof. Geinitz is, so far as known to
the writer, new, and may be called Pleurophorus subellipticus.

CL (Pleurophorus) simplus von Keyserling. Geinitz, ib., fig. 5.
Prof. Geinitz did not have specimens of this shell from Nebra&ka,
but gives a figure copied from Dana's Geology of a specimen
from the Permian rocks of Kansas. It is the P. subcuneatus M.
& H., and ooeurs both in the Permian and Permo-carboniferous
beds. It varies considerably in form, and some of the varieties
like that figured in Prof Dana's Geology resemble P. simplus^
though among all of the hundreds of examples I have seen, not
one is proportionally so slender and elongated as the figure of
the Russian shell. Nor have any of them the posterior hinge-
teeth prolonged nearly so far backward.

CUdophorus solenoides Geinitz, ib., fig. 7. This is a good spe-
cies of genus ?

* Prof. King says Prof. Geinits formerly oonfoimded PUurcphanu eottaiut with
the edentulous so-called* ify^i/tM FaUan.



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182 Review of Creinitz on the rocks and fossils of Nthratka.

Aucella Hausmanni Goldf. Geinitz, ib., fig. 8. This is doubt-
less a Myalina resembling the M. squamosa of England, but it
is less nearly like M. Hausmanni^ as figured by Goldfuss, and
quite unlike Prof. Geinitz's figures of German specimens referred
to that species. It is doubtless the same as Myalina Swalloti of
McChesney, from the Missouri Coal-measures. I have also se^
a similar form from beds in Nova Sootia, referred by good au-
thorities to the Sub-carboniferous.

Mytilus concavus? Swsllovf. Geinitz, ib., fig. 9. This is not
the form described by Prof. Swallow, which has angular instead
of rouoded umbonal slopes. It may be a Myalina but it is cer-
tainly not a true Mytilus. *

Myalina perattenuata M. & H. Geinitz, ib., fig. 10-11. Cor-
rectly identified, but it is specifically distinct from JW. permiana
Swallow (cited by Geinitz as synonym), which has less attenu-
ated beaks.

Myalina suhquadrata Shumard. Geinitz, ib., figs. 25 and 26.
Correctly identified. It is common in the upper Coal-measures
of this region, and has been found by Dr. White in the same
horizon in Iowa.

Avicula speluncaria Schlot Geinitz, ib., fig. 12. As already
stated, this belongs to Bey rich's genus Pseudomonotis, The
specimen figured by Prof/Geinitz is not from Nebraska, but
was sent to him by Prof. Dana from the Permian beds of Kan-
sas, and is the same shell described by Dr. Hayden and the
writer under the name Monoiis Hawni* It nearly resembles
the European species speluncaria, and may possibly be identical,
but good European specimens of that species now before me
can be distinguished from the American form. At any rate we
have a specimen from a bed of nearly black limestone, far down
in the Coal-measures at Leavenworth, Kansas, agreeing even
more nearly with P. speluncaria than P, Hawni does, bimilar
forms occur at different horizons in the Coal-measures and Per-



Online LibraryJohn AlmonThe American journal of science and arts → online text (page 72 of 102)