inhabiting the United States. 373 
tremity slightly tinged with the same.  Tentacule | 
slender, cavities into which they are retracted visi- 
ble, foot narrow, twice as long as the diameter of 
the shell. 
Shell. Depressed, very slightly convex on the 
upper surface ; epidermis whitish horn-color, some- 
times with a tinge of green, at other times with rusty- 
yellow ; whorls five, above flattened, below rounded, 
finely striate obliquely, the outer whorl spreading a. 
little towards the aperture ; wabilicus wide, deep, 
exhibiting all the volutions to the apex; aperture 
rounded, somewhat flattened above, its edge fre- 
quently tinged with reddish brown ; dip sub-reflected 
at the base of the shell, simple above, and in some 
. specimens considerably depressed near its junction 
with the outer whorl ; columella with a thin callus, 
the edge of which connects the upper and lower 
extremes of the lip. 
Greatest transverse diameter one inch and one 
eighth. Common size half an inch. 
GrocgaAPmicanL Distrisution. This species has 
been noticed in. Vermont, Virginia, Georgia, Ohio, 
Illinois, Missouri, and the Northwestern Territory, 
and has been brought lately from. the shores of Co- 
lumbia River, where it is said to be common. It may 
therefore be considered to inhabit the whole — 
of the United States. 
REMARKS. | ` This shell, though frequently seen, 
does not seem to be so numerous in our forests as 
some other species. -It is peculiar for the elegant 
rounded shape of the whorls, as seen on their lower 
surface. It rarely varies from the common type, and 
