70 
-which Eaton has called Geoclic limestone , 
contains great many cavities similar to 
the volcanic Geodes and filled with cris- 
tals, while in Ohio, Kentucky &c. and 
chiefly in the Wasioto or knobhills, the 
cherty limestone and even the sandstone 
above it, contain many free geodes per- 
fectly silicified like the other fossils, fill- 
ed inside witlv fine cristals of quartz. 
These geodes which I have called geo- 
dites in my enumeration, appear to me 
to be fossil animals, like those of the 
chalk distinguished by Patrin. They 
are always thick, often smooth, without 
cyclorites or orbiculites. Some are very 
large, I could have collected many, but 
they were too heavy to carry. They are 
often found abundantly in the ravines, 
glens, and torrents of the hills, mixed 
with rolled stones. 1 have seen some cal- 
cedonised. It is sometimes needful to 
break them to ascertain their geodic na- 
ture, as the outward appearance is delu- 
sive. 
But if they were animals, as they have 
no visible mouths, they must have been 
porostomes become fossils. See my letter 
to Cuvier upon the porostomes. 
They will always be easily distinguish- 
ed from the chert and siiicious fragments 
of jasper, quartz, & c. imbedded in the 
cherty limestone by not being in any way 
angular, nor ringed. 
Many kinds or species can be distin- 
guished among them, but they often run 
into each other by gradual forms or co- 
lors. The G. levigata of mv enumera- 
tion, sp.74, would probably include many 
such. The colors are variable, but chief- 
ly uniform in each specimen, the whitish, 
yellow and rufous are most common, but 
various shades of red and brown are also 
found. The sizes vary from that of an 
orange to the size of a man’s head, weight 
from 1 to 25 pounds. 
The following kinds offer the most 
striking forms. 
1. Geodites levigata , Raf. Commonly a 
little elliptical, not compressed, nearly 
smooth. 
2. G. Cdmpressa. Elliptical, compressed 
one side smoother than the other. 
3. G. Sulcata. A little elliptical, with 
some furrows or wrinkles unequal and 
irregular. 
4. G. Globosa. Globular, smaller than 
the others, a little rough. 
5. G. Phaiops. Oblong, nearly smooth, 
dark brown. 
6. G. Ovoidea. Ovoidal smooth, one end 
smaller. 
7. G. Mamila. Elliptical, somewhat 
mamillar outside. 
8. G . Eryihrea, Red, oblong, smooth. 
• - \ 
■ t } 
9. G. Bivisa . Oblong, with a partition 
in the cavity inside. 
10 G. Biloba. Oblong, bilobe, with two 
rounded parts nearly equal. 
11. G. Lobata. With many unequal ir- 
regular lobes. 
12. G. Elongata. Long oblong, nearly 
cylindrical, smooth. 
13. G. Cavernosa . Irregular with seve- 
ral cavities. 
14. G. Amorpha . Amorphous, unshape- 
ly, a single cavity. 
15. G. Bispar. Oblong, with a large 
chink on one side. 
16. G. Turbinata. Nearly turbinate, 
rough, one end attenuate, the other con- 
vex depressed, cavity small. Very singu- 
lar sp. fulvous uneven outside, inside 
changed in white quartz, cavity within 
with mamillar crystals. 
16. On the Cavulites and Antrosites. 
My N.G. Cavulites follows the geodites 
in my enumeration. It differs chiefly by 
having outward cavities or openings to 
the internal cavities. The cavulites which 
contain asqnany sp. as the geodites, are 
not therefore porostomes , but may be true 
alcyonitesor spongites having mouths or 
openings to the internal stomach or ca- 
vity. 
Another N. G. of mine, which T call 
Antrosites , forms the link between them. 
It has no outward cavities, but a single 
large opening or hole communicating 
with the internal cavity. A living sea G. 
of Sicily called by me Megastoma in 1814 
comes very near to this, but here the 
opening is still larger and the body is 
fixed not free. This Megastoma is how- 
ever a very singular animal. It is called 
cedvu di mart or sea citron in Sicily, re- 
sembling outside a large citron rough or 
somewhat mamillar, inside quite smooth, 
substance thick cartilaginous. Fixed on 
rocks nearly inert, yet alive, since when 
cut jt appears to shrink from the knife. 
The cavulites and antrosites have many 
species, of as many colors as the geod- 
ites; but their size is always smaller, and 
they are more rare, some sp. very much 
so. 1 shall give here a few of them: but 
figures should be required to make them 
well knovvn; they will be figured here- 
after. 
1. G. Cavulites. 
1. C. ambloides. Subglobose, outward 
cavities smalhand unequal, few inside and 
small. 
2. C. anastoma. Oblong, cavities al- 
most anastomosed, large cavities inside. 
3.. C. geodica. Ovoidal, large cavities 
outside, only one inside, hardly commu- 
nicating. 
