
2 49 : 
prominent tubercles on the body whorl, and one re- 
volving near the base of each whorl of the spire; su- 
ture profoundly impressed, margined by an obtuse 
subnodulous prominent line; lines of growth very ob- 
lique and prominent; obscure spiral strie; epidermis 
olive; within bluish, often with purple bands. 
OBSERVATIONS. 
A beautiful species when perfect, occurring in 
vast abundance on the masses of calcareous rock, 
which have fallen from the strata above, into the 
Alabama river, at Claiborne. I found it living only 
in such situations, and exclusively within a range of 
six or eight miles. In the Tombeckbe or Black War- 
rior rivers, I never observed a specimen of it, 
although I searched particularly for it on the rocks at 
St. Stephens. 

MELANIA EXCURATA. 
Puate IV.--Fig. 6. 
DESCRIPTION. 
Shell subulate, with a spiral band of slightly oblique 
subcompressed tubercles on the base of the inferior 
whorls; above this is a prominent line with a slight 
intervening channel; volutions towards the apex 
nearly entire; base with three prominent lines, the 
superior one largest; the third hardly prominent and 
approximate to the middle one, 
E 


