274 DIMYARIA.—CYPRINADA, 
cor; it ranks among the largest of our Mollusca, 
being sometimes found nearly three inches in 
length, and the same in breadth and thickness. 
It is of an uniform dark brown or liver-colour. 
The following interesting account of the animal 
and its habits was communicated by the Rev. James 
Bulwer to the second volume of the “ Zoological 
Journal.” 
HEART-SHELL. 
“Mantle completely lining the shell, double at 
the outer edge; exterior fold divided in_ front, 
open at each end; at the posterior end forming two 
short siphons or tubes, ciliated at the upper orifices ; 
colour, yellowish white ; margin, orange. Foot very 
muscular, broad, triangular, compressed, pointed, 
orange. Branchiz external, concealed between the 
