CLASS ANNULATA. 
ORDER SEDENTARY ANNULATA. 
FAMILY DORSALIA. 
GENUS SILIQUARIA. Lamarck. 
S. Claibornensis. Plate 1. Fig. 1. 
Description. Shell round and spirally tapering, longi- 
tudinally and indistinctly furrowed; fissure inarticulated. 
Observations. Not having obtained a complete specimen, 
I am unable to give a perfect figure of this species. Among 
the fractured pieces are two which, by two or three rapid 
turns, form nearly a complete apex. In some, transverse 
septa, as mentioned by Lamarck, are found. These are 
very thin and hemispherical, the convex side being to- 
wards the apex. In some fragments the fissure is closed 
on the inside. I presume this takes place below the upper 
septum; but I cannot decide upon the few specimens in 
my possession. The furrows on some specimens are very 
perceptible, on others obsolete. One of the fragments is 
E 
