29 
wedge-shaped as in the last, a character that distin- 
guishes it in all ages. The posterior lobe is well defined 
and gibbose. 
I have several specimens of this shell from Bradford, 
Wilts, and from Claverton Hill, near Bath. I believe 
it belongs to Smith’s Fullers’ -earth Rock. 
MODIOLA reniformis* 
TAB, CCXI. — Fig. 3. 
Spec. Char# Oblong, sub-reniform, smooth ; 
anterior lobe slightly expanded; posterior 
lobe small. 
A more obtuse and less curved shell than the last, and 
comparatively compressed : the length is about twice the 
width. 
This shell, of which I have seen but one specimen, is 
said to be from the inferior Oolite, near Bath. 
