4. G. unka. Elliptical, a single cavity 
inside, few outside unequal, one united 
to the interior, 
5. C. vermicidaris. Unshapely, with 
vermicular cavities outside and inside. 
6. C. amorpha . Unshapely, cavities 
rdunded unequal. 
7. C. equalis. Subglobose, cavities near- 
ly equal, few inside. 
8. C. depressa. Elliptical compressed, 
cavities unequal, only one or two inside. 
2. G. Antrosites . 
l.'A. globosa . Globular, surface nearly 
smooth; small opening, large cavity. 
2 A. elliptica. Elliptical, surface a lit- 
tle rough, opening at one end, large ca- 
vity. 
3. A. camerata. Ellipsoidal, surface 
nearly smooth, opening lateral, cavity db 
vided by partitions* 
4. A. depressa, Ellipsoidal, depressed, 
nearly smooth, opening very small termi- 
nal. 
5. A. nodosa . Rounded surface, knob- 
by or mamillar, opening Small, cavity ir- 
regular. 
6. A. magna. Amorphous rough, un- 
even, opening large, cavity lobular. 
7. A. dispherica. Formed by two united 
lobes founded, nearly smoothy opening 
irregular. 
8. A. rimosa . Ovoidal with many chinks, 
opening and cavity large. 
9. A. incurva. Oblong curved irregu- 
lar, opening terminal, cavity small. 
10. A. ditrema. Oblong nearly smooth, 
two unequal openings, one at each end, 
cavity large. This last ought perhaps to 
form a peculiar genus* by having two 
openings, and be called Ditremites levis. 
All these animals or fossils are entire- 
ly silicious like the geodites. The antro- 
sites have often cristals inside, but the 
cavulites very seldom. They are from 
the same locality and chiefly from East 
Kentucky. 
17. On the Genera of fossil Trilo bites or 
Glomerites of North America . By C. 
S. liAFlNESQJJE, 
Philadelphia, May, 1832. 
Prof. Green of Philadelphia, is 
engaged' in the investigation of all 
the Trilobites of the U, States; a 
labor very much wanted; as these 
interesting fossils are very nu rner- 
ous with us, and but few as yet pro- 
perly named and described. Instead 
of figures he will give colored .casts 
in piaster of all those he can procure. 
This improvement is novel here and 
will be very acceptable to the oryc- 
10 
tologists. He has already issued in 
April a first series of 8 casts^ and 
species accompanied with a synop- 
tical table, among which a N.G. di- 
pleura and 4 new species of G.asa - 
plms and calymene. He Kks omitted 
the geological localities, but will 
probably supply this deficiency in his 
monograph, 
I was among the first to attend to 
the trilobites in N. America, In 1817 
Dr. Schaeffer presented the first spe- 
cimen from the Catskill mts. to the 
Lyceum of New-York, as a fossil 
quite unknown, I pronounced it a 
new genus of fossil entomostraceous 
crab, and called it Glomerites eury - 
cephala in a paper read before the 
Lyceum | being very near to the G. 
glomeris of Latreille orarmadillo of 
Cuvier. 
. Soon after I found in the work of 
Parkinson, that he had been the first 
to notice these fossils, under the 
name of Trilobites , a very good and 
precious name, 
Brongniart in his excellent work 
on the trilobites, published in 1822, 
but which he claims to have read be- 
fore a society in 1815; divides them 
into 5 genera, and abolishes without 
just cause the name' of trilobites; 
which ought to have been left to the 
group calymene : and must yet be 
restored, because there is a previous 
G. calymenia of Kuiz and Pavon in 
botany. 
Much discussion and controversy 
has taken place on the subject of 
these animals, some deeming them 
shells near to chiton ; but the pre- 
sence of eyes in many of them fixes 
them among the crabs; altho* their 
feet being small und soft, have been 
obliterated in the fossilization. 
In 1821, Lsentto Europe the de- 
scription of 12 American trilobites, 
and I published in Kentucky the N, 
G I si ctomesa. 1 ' , 
In 1824 Dr. Cay produced it again 
under the name of isoteles and in 
1826 Dolman calls it nileus < 
Dolman has described many Eu- 
ropean species; we have nearly as 
many in North America, offering 
