336 On the Secondary and Tertiary Formations. 
promiscuously together in great confusion ; single valves of the 
bivalves are more frequently found than. the two together, and 
even the stronger univalves are most often seen in fragments, 
So abundant are they, that in cleaning out some of the larger 
shells a great number of small and more perfect specimens were 
found in their. interior, and added to my collection. A Pectun- 
culus quinque-rugatus, in particular, enclosed between its two 
valves a multitude of shells and fragments closely imbedded in 
a fine clear quartz sand. The contents when picked out occu- 
pied a space full twice that in which they were so closely 
packed, Although the diameter of the Pectunculus: was only 
two inches and one fourth, there were in it a Cytherea reportas 
beautifully preserved with its natural polish, one and one third of 
an inch long, and itself filled with other smaller shells and.a 
purer sand than that which surrounded it—several small Ostres, 
Corbule,and duplicates of twenty or thirty other species. There 
are, as seen by the accompanying catalogue, about 80. species 
found at this locality. Of these 12 are recent, and 20 at least 
heretofore undescribed. Some yet undetermined remain in the 
hands of Mr. Conrad, and of these only the genera are given. 
The Oliva idonea has been previously described by Mr. Conrad} 
it is one of the most beautiful shells. found: here, being fuely 
preserved, and most of the specimens not having lost their nat 
ural polish. The people living in the neighborhood know: them 
by the name of “ key shells,” from their procuring them to attach 
to a-bunch of keys. ‘The cones are of the species adversarius; 
the only exception known. The bivalves are only occasionally 
- It is remarked that the water in the well never varies in fresh- 
ets nor droughts, and tales are told of ineffectual attempts hav- 
ing been made to sound it,.and of a. strong current .settlng 
through it, sucking down whatever is thrown in that there 8@ 
current I doubt not, it- being. nothing unusual for a stream % 
Eutaw springs in South Carolina, and the limestone of the se 
ondary formation I believe to be not far below the surface of the 
Water, perhaps directly under the blue sandstone at the surface, 
fe 
