The Cabinet of Dr. Joshua J. Cohen.
The Cabinet of the Baltimore College.
The Cabinet of the Atheneum.
The Baltimore Museum.
————
The Cabinet of Professor Hall, Mount Hope.
TRILOBITES, &c.
·—▸⏵►●◓●◄⏴◂—·
Genus Calymene. _Brongniart_.
The name of this genus is derived from a Greek word which signifies
_obscure_ or _concealed_. The fossil animals included by it are
characterized as having contractile bodies; the buckler as bearing many
tubercles or folds--the cheeks as being oculiferous, and the abdomen
and tail as being composed of from twelve to fourteen articulations
or joints, without any membranaceous expansion. The Calymenes in
thickness are nearly semicylindrical, and the buckler in front presents
a _chaperon_ or upper lip more or Jess raised. In perfect specimens,
there is a small furrow which seems to indicate a separation between
the upper and under parts of this kind of lip. The eyes are always
raised, and frequently present the remarkable structure observable in
many of the _crustacea_; but as this part is generally very prominent,
the _reticulations_ of the eye are commonly worn off or injured.
Professor Brongniart places but little confidence in any of the generic
characters above enumerated, except the number of articulations of the
abdomen: these, however, in our opinion, are more vague and uncertain
than most of the others. The genus, however, we think may be readily
identified, after becoming familiar with one well characterized
species. The general aspect of the buckler is peculiar--the body is
not so depressed as in most other genera, and the lateral lobes are
destitute of all membranaceous expansion.
To the genus Calymene, belongs the celebrated Dudley fossil, called
_Entomolithus paradoxus_ by Blumenbach, but which is not the same
organic relic, to which Linné applied that name.
This genus includes a great number of species, and though some of them
are said to be found in different and distant parts of the globe, they
are according to our limited observation, for the most part confined,
like recent species of animals, to particular districts. The C.
polytoma, C. pulchella, C. bellatula, C. concinna, C. sclerops, and
the C. punctata, all finely figured by Professor Dalman, and which
are found in Sweden, have not yet been noticed in any part of North
America.[12]
[Footnote 12: See the valuable and extensive communication of J. W.
Dalman, M. D., on the Trilobites, in the Transactions of the Swedish
Academy for 1820, part 2d.]
Calymene Blumenbachii. _Brongniart._ Cast No. 1.
Clypeo rotundato, tuberculis sex distinctis in fronte; oculis in
genis emintissimis; corpore tuberculato.
In this species the upper lip presents a furrow parallel to its edges.
The lip is straight. The cheeks are a little projecting. There are
six rounded tubercles on the front, and fourteen articulations on the
back; the tail is small, and the shell is covered with small rounded
tubercles of unequal sizes.
The above is Professor Brongniart's description of this trilobite,
which is the famous Dudley fossil described and figured by Littleton,
in the Philosophical Transactions, (London) in 1750. According
to Dalman, several distinct European species have been published
under this name. The true C. Blumenbachii, he says, has thirteen
articulations to the abdomen, and about eight to the tail. In the
cabinet of G. W. Featherstonhaugh, Esq., we have examined a fine
perfect specimen from Dudley,[13] in which there is fourteen abdominal
joints. There can be no doubt, however, that several species have been
confounded under the name of C. Blumenbachii; Dalman's C. Tuberculata
and C. Pulchella are, we think, distinct from it, though he has marked
them only as varieties.
[Footnote 13: This famous trilobite, once formed a part of the cabinet
of Mr. Parkinson, the distinguished author of the "Organic Remains,"
and is accurately figured on one of the plates of that splendid work.
At the sale of the late Mr. Parkinson's fossils, it was purchased by
Mr. Featherstonhaugh,]
The true C. Blumenbachii, no doubt, abounds in North America, and is
one of the few examples of the occurrence of an identical species
on both continents. The late Abbe Correa sent a perfect specimen to
Brongniart, from the vicinity of Lebanon, in the state of Ohio. We
have also seen a number of specimens from that state, which could not
be distinguished from the Dudley trilobite. Our model was taken from a
specimen found at Trenton Falls, in the state of New York.
The three following species found in the United States, will no doubt
be considered by many as mere varieties of the C. Blumenbachii; we have
ventured, however, to call them by distinct names.
Calymene Callicephala.[14] _Green._ Cast No. 2.
[Footnote 14: From two Greek words, which signify "beautiful head."]
Clypeo antice attenuato, figura liliiformi in fronte depicta;
oculis minimis; abdomine quatuordecim articulis; corpore plano.
The buckler is subtriangular; on the front there is a figure in high
relief, somewhat resembling a _fleur de lis_; or perhaps more, the
capital of a Corinthian column. The oculiferous tubercles are rather
lower down on the cheeks than usual. The articulations of the abdomen
and the tail cannot well be distinguished from each, other; fourteen
in all may be easily counted. The middle lobe of the abdomen is nearly
equal in breadth throughout. The ribs, or costal arches, are not
grooved or bifurcated at their extremities. Length nearly two inches
and a half.
This beautiful species is in the Philadelphia Museum, where it is
labelled as being found in "Hampshire, Virginia." It is mineralized by
a dark yellowish limestone. It differs from the C. Blumenbachii, in
the form and number of its articulations; in the shape of the head; in
having only two flat tuberculous elevations on the front; and in other
particulars.
In the cabinet of the New York Lyceum, and in that of J. P. Wetherill,
Esq. there are some examples of this species from the Miami river, near
Cincinnati, Ohio. I have also seen it from Indiana, in a dark coloured
limestone, very much distorted. It has never been found at Trenton
falls, or at any other locality, as far as my knowledge extends, which
yields the true C. Blumenbachii.
Calymene Selenecephala.[15] _Green._ Cast No. 3.
[Footnote 15: From the Greek for "lunate head."]
Clypeo antice rotundato, margine omni valde incrassato; prominentia
frontali utrinque trituberosa; corpore tuberculato.
The buckler is regularly lunate; the margin is slightly reflected or
raised anteriorly, the posterior edge forms a continuous rim, running
nearly parallel with the articulations of the abdomen. The front on
each side has one large and two small tubercles, near its superior
edge. The oculiferous tubercles on the cheeks are on a line with the
lowest frontal tubercle. There are fourteen distinct articulations;
but as the tail is mutilated and distorted, the total number of
joints cannot, from this specimen, be ascertained. The body appears
to have been covered with small pustules. These are very evident on
the front. Costal arches simple, or not grooved. Length, one inch and
three-fourths, breadth of the buckler one inch and one-fourth.
This species resembles a little the C. Pulchella of Dalman. The
specimen from which the model was taken, is in the possession of Mr.
R. Peale, of New York, who willingly lent it for this monograph. He
informed me that it was found in the state of New York, but he was
unable to name its precise locality. It occurs in a soft ash coloured
limestone. No other petrifaction is observable in the fragment of rock
which contains it.
Calymene Platys.[16] _Green._ Casts No. 4 and 5.
[Footnote 16: From a Greek word which signifies Flat,]
Clypeo antice rotundato; prominentia frontali utrinque quatuor
tuberculis.
The buckler is probably semilunate; but as the anterior portion is
lost, this cannot be determined with precision. The posterior raised
rim is not continuous, as in the C. Selenecephala, but is separated by
the longitudinal dorsal furrows. The front is distinctly divided from
the cheeks, and has four tubercular prominences on each side. Three
of them are nearly on a line with the lateral edge of the cheeks, and
gradually diminish in size, as they descend to the anterior part of
the buckler. The other is smaller, and is between, and a little to
the side, of the upper two. The cheeks form spherical triangles. The
oculiferous prominences are close to the second large tubercle on the
front. The cheeks are, however, quite imperfect. The articulations
of the back cannot be distinguished from those of the tail. In our
specimen they are all beautifully distinct, and are twenty-two in
number. The posterior raised rim of the buckler seems to form an
articulation; its extremities on each side are a good deal thickened
and expanded. The costal arches suddenly curve downwards and backwards,
near their middle, so as to divide the abdomen and tail into five
unequal sections. The whole length is nearly three inches. The breadth
of the buckler nearly two inches.
This fine large Calymene was accidentally discovered on the Helderberg
mountain, by my friend, Professor T. R. Beck. One of the loose pieces
of sandstone rolling over, near his feet, presented him the fine
natural mould, from which he has kindly permitted our cast to be taken.
The animal relic once enclosed in this matrix, must still be near that
locality, and yet remains undiscovered, to reward the enterprise of
some more fortunate naturalist.
One of our models represents the natural mould found by Dr. Beck. The
other is a cast taken from it and exhibits, more satisfactorily, the
various parts of the animal.
Calymene Microps.[17] _Green._ Cast No. 6.
[Footnote 17: From the Greek for "small eyes."]
Clypeo antice subattenuato; occulis minimis in lateribus capitis;
abdominis articulis a 14 ad 18; corpore depresso.
The buckler is semi-elliptical, slightly punctate, and much depressed
anteriorly; the front and cheeks are not very distinctly marked. The
eyes are very remote from each other, being situated near the posterior
lateral angles of the head. They are not very prominent, and exhibit
no marks of being reticulated. Before the eye on each side, there is
a slight transverse indentation. It is difficult to distinguish the
articulations of the abdomen from those of the tail. They are from
fourteen to eighteen in number. Where the lateral lobes remain perfect,
two narrow raised lines appear between each of the ribs; these are
most evident on the caudal extremities of the animal. The middle lobe
is in the form of a long, slender, and acute cone. The whole animal is
an inch and a quarter long, and is much more depressed than any other
Calymene which we have seen.
I am indebted to Mr. Titian R. Peale for the use of the original from
which our model was taken, his liberality to those who cultivate
Natural History is proverbial, and needs no encomium from me. The C.
Microps is said to have been found near Ripley, Ohio. It occurs in
black limestone.
The eyes of this Calymene are small in comparison with those of some
other species--particularly the C. Bufo, C. Macrophthalma, and C.
Anchiops.
Calymene Anchiops.[18] _Green._ Cast No. 7.
[Footnote 18: From two Greek words which signify "eyes approximate."]
Clypeo antice, caudaque postice rotundatis; oculis approximis,
magnis, excertis; articulis vigenti; corpore plano.
The buckler of this species is irregularly hemispherical; the front
pyriform and without pustulations. The cheeks are almost entirely
occupied by the eyes, which are placed very near each other on the
upper part of the forehead; are very large and trilobate, the side
lobes being elongated and attenuated in front. The articulations
of the back are twenty in number, those of the abdomen not being
distinguishable from those of the tail. The costal arches of the side
lobes are round near their extremities, and are intersected with two or
three raised lines. Length nearly four inches. Breadth about two inches.
It gives me great satisfaction in being able to describe, and to
present to naturalists a good cast of this Calymene, which has
excited for a long time so much interest and perplexity. The original
fossil from which our plaster model was made is now deposited in
the cabinet of the Albany Institute, and is the identical specimen
from which a cast was long since made, by Dr. Hosack of New York, a
specimen of which he sent in July, 1819, to the Royal Academy of
Science, in France. Professor Brongniart referred the animal from
which this model was taken, though with much hesitation and doubt,
to the species, Calymene Macrophthalma. He remarks concerning it,
"Il est beaucoup plus gros que les autres individus, et a prés de
dneuf centimètres de longueur. C'est avec doute que je rapporté
cette empreinte tres-peu nette à l'espèce actuelle; mais malgré ses
formés obtuses, et l'absence de tout detail, elle est si remarquable
par la grosseur de ces yeux et par le prolongement de son bouclier
qu'on peut présumer qu'elle appartient an calyméne macrophthalme, et
avec d'autànt plus de probabilité qu'elle vient aussi des Etats Unis
d'Amérique. Elle a été trouvée, suivant M. Hosack, dans un schiste."
We have seen the cast alluded to in the above note, and are not at all
surprised at the uncertainty which it has occasioned. The apparent
prolongation of the buckler is entirely occasioned by the loss of a
small fragment from that portion of the head. The form and position of
the eyes, further distinguish it from any of the numerous specimens
of C. Macrophthalma, that we have examined. The raised lines which we
have noticed as intersecting the costal arches of the lateral lobes
are remarkable, though they may have been produced by accidental
fissures in the epidermal covering of the animal. The head of the C.
Macrophthalma is always marked by minute and prominent granulations,
like _shagreen_--nothing of this kind appears on the buckler of the C.
Anchiops.
I am informed by my friend, Dr. T. R. Beck, to whose liberality I owe
this interesting species, that it was found in Ulster county, New
York. It was supposed by Dr. Hosack, to have been discovered in the
vicinity of Albany. Respecting the locality and geological relations of
this trilobite, Professor Brongniart remarks, "un modéle en plâtre de
trilobite envoyé à l'Académie des Sciences, en Juillet, 1819, par M.
Hosack, et que j'ai rapporté, autant que la chose était possible, et
toujours avec doute, au calyméne macrophthalme, a été trouvé dans le
territoire d'Albany, êtat de New York. Or, les environs de cette ville
sont indiqués, sur la carte géologique de M. Maclure, comme formés de
terrains de transition. M. Hosack dit qu'il a été trouvé au milieu d'un
rocher ardoisé, c'est à dire, dans un schiste probablement analogue à
celui des environs d'Angers, qui renferme les Ogygies, et ce trilobite
ce rapproche un peu de ce genre par la grosseur des tubercules qui
recouvrent les yeux on en tiennent la place." The rock in which the
Calymene Anchiops is found, appears to be a clay slate.
Calymene Diops.[19] _Green._ Cast No. 8, and fig. 2.
[Footnote 19: From the Greek for "Double Eyes."]
Clypeo lobato plano; rugis tribus in lateribus frontis; tuberculis
oculiformibus, eminentissimis et duplicibus; articulis octodecim;
cauda rotunda.
This species is very distinct from every other Calymene that we have
seen. The outline of the buckler is lobate lunate; the front is very
convex, and a good deal elevated above the cheeks or sides, from
which it is divided by a deep furrow; on the posterior margin of the
front on each side, close to the groove there is a prominent circular
tubercle, before which there are three small transverse wrinkles.
The cheeks are subtriangular; the oculiform tubercle is near the
posterior superior angle, and is only separated from the tubercle on
the front, by the furrow or groove, so that the animal seems to have
had double eyes on each side; there are two curved lines on each side
below the eyes, crossed near the front by a deep short canal. The
middle lobe of the abdomen and tail is rather longer than the lateral
lobes, and is rounded and very prominent throughout. It is composed
of 18 articulations, seven of which appear to belong to the tail; it
is, however, somewhat difficult to define the length of the tail with
precision. The costal arches of the lateral lobes, particularly those
near the tail, are bifurcate. Length almost three inches.
The original fossil, from which the cast was taken, is in the New York
Museum. I am indebted to Mr. Rubens Peale, the liberal proprietor of
that flourishing and important institution, not only for the use of
it in this Monograph, but also for some valuable information relating
to other species. The precise locality of Mr. Peale's specimen is
not known, but in the cabinet of J. P. Wetherill, Esq., there is a
fine head of the C. diops which was found in the State of Ohio. Both
specimens are mineralized by the same kind of soft grey coloured
limestone--and I have but little doubt that they were derived from the
same place.
Calymene Macrophthalma.[20] _Brongniart._ Cast No. 9.
[Footnote 20: From the Greek for "Great eyes."]
Clypeo antice, caudaque postice attenuatis, oculis magnis exsertis.
This species, according to Al. Brongniart, who first described it,
is remarkable for the magnitude and protuberance of its eye-shaped
tubercles, and by the prolongation of the anterior portion of the
buckler, in the form of a snout.
The back is marked by 12 or 13 articulations, which are thicker than
those of the tail. The tail is short, pointed, and without expansion.
The middle lobe, or front of the _buckler_, in this calymene, is said
by Brongniart to be marked on its sides by three oblique plicæ or
wrinkles, but we have not been able to discover this character in any
of the specimens to which we have access; neither do they exhibit any
remarkable prolongation in the anterior portion of the _buckler_, as
stated in his specific character. The specimens which we have examined,
agree pretty well with the representation he has given of the C.
Macrophthalma, Plate I. fig. 5. A. B. & C. made from a drawing by Mr.
Stokes, from a fossil found in Coalbrookdale (Eng.).
This trilobite is common in several parts of the United States.
According to Dr. J. E. Dekay,[21] the C. Macrophthalma is found on
the Helderberg mountains, near Albany, and at Coshung creek, not
far from Seneca lake, in the State of New York. It occurs also at
Leheighton, in Pennsylvania--at the Falls of the Ohio, and at several
other localities. We have examined a number of specimens of the C.
Macrophthalma, contained in the rich cabinet of fossils, in the Academy
of Natural Sciences, and have never seen any individual which resembles
the fig. 4, Plate I. of Brongniart; and in no instance is the front
of the buckler marked by three oblique folds, a character stated as
peculiar to this species. The C. Macrophthalma, (variety) occurs in
large quantities in Leheighton in Pennsylvania, and we are indebted to
Mr. D. Keim, for some fine specimens from that locality.
[Footnote 21: See Annals of Lyceum, Vol. I. p. 188.]
The authority of Professor Brongniart is sufficient to place the C.
Macrophthalma among the species of the United States, though we have
been unable fully to identify it with his description.[22] He received
a specimen, transformed into red jasper, from Prof. Ducatel, said
to be found in the United States--no precise locality is given. Our
model represents the animal which is supposed to be the one intended
by Brongniart as the C. Macrophthalma of North America. It is, in our
opinion, a variety of the C. Bufo. There can be no doubt that several
species have been confounded under the name of C. Macrophthalma.
[Footnote 22: We have seen in the Cabinet of Mr. Featherstonhaugh, a
fine group of trilobites, in the transition limestone, from Dudley,
(Eng.) Among them there is a perfect head, which agrees exactly with
the description given by Mr. Brongniart of the head of his Calymene
Macrophthalma. If this belongs to the true macrophthalma, our species
under that name is entirely distinct. Since our work had been prepared
for the press, Dr. J. J. Cohen, of the Baltimore College, has shown
us the fragment of a calymene from Berkley, Virginia, which agrees
with Brongniart's description of the macrophthalma, and with the above
fossil from Dudley. We regret that the imperfection of the fossil
prevents our giving a satisfactory cast of it.]
The following extract of a letter from Professor Ducatel to the author,
referring to the locality of this species, will be read with interest.
"I cannot be positive as to my recollection of the locality of the
fossil referred to by Brongniart and yourself, but believe it is one
of several found by my friend Dr. M'Culloh, in the neighbourhood of
Berkley Springs, Virginia. I regret that I have not in my possession
another specimen to present to you."
Calymene Bufo. _Green._ Cast No. 10.
Clypeo rotundato, convexo, punctato; abdominis articulis sexdecim;
cauda attenuata; corpore plano.
Buckler semilunate, front very large, rounded before and arcuated at
the insertion of the middle lobe; surface convex, and marked with
numerous depressed pimples. Mouth large, lunate, resembling that of
a toad or frog, with a narrow raised rim on the upper and under lip.
Below the chin there are no pustulations. Cheeks small, triangular,
and separated from the front by a deep, rectilinear furrow; the eyes
in our specimen are much injured, but they are large, and near the
upper angle of the cheeks. Middle lobe with a series of distinct double
articulations. Lateral lobes wider than the middle lobe, ribs deeply
grooved near their insertion; articulations of the abdomen twelve; of
the tail ten. Length four inches and a half; breadth of the buckler
nearly two inches.
This fossil was presented to me some time since by Thomas P. Johnson,
Esq., who mentioned that it was found in New Jersey, but that he could
not learn its precise locality. Near Patterson, in that State, some
trilobites have been discovered--perhaps the C. Bufo may have been
derived from that locality. It is composed of a dark greyish limestone,
easily cut with a knife.
Calymene Bufo. Variety, Rana. Cast Nos. 11 & 12.
This fine specimen differs from the one above described, in having the
front of the buckler rather smaller, and of a different contour. The
whole of the shell is also covered with granulations, which only appear
on the head of the other; this, however, may be only an imperfection in
the specimens in our cabinet.
I am indebted to the Albany Institute for the originals of the models
Nos. 11 & 12. They were found at Seneca, Ontario County, New York, in
dark, slaty limestone, which also contains cubical crystals of iron
pyrites. A fortunate blow of the hammer has fractured the rock which
contains this trilobite, so neatly, as to present us at the same time
with the petrified animal in an almost perfect state, and also with
the mould or matrix in which it was imbedded. This arrangement is
beautifully illustrated by our models.