THE ECON'OMIC MOLLUSC A OF ACADIA. 



S9 



is evidently common in the Gulf of St. Lawrence, from Bay 

 Chaleur to Cape Breton. It seems strange, however, that it 

 should be reported as being common all around the coast of 

 Nova Scotia, when it is totally unknown upon the Bay of 

 Fundy coast of New Brunswick. It is probably to be found 

 wherever the Oyster lives, and being somewhat more hardy, 

 occurs rather beyond those limits. 



Habits. This species is well-known to all oystermen and frequen- 

 ters of fish-markets. It is a bivalve shell, having two very thick and 

 heaw valves of a dingy white or ash color. Upon these are weli 



Fig. K. — Vemis mercenaria. Natural Size. 



marked, very regular, concentric folds, which become quite sharp where 

 not wcin by friction. Inside they are chalky while, except at the 

 smaller end, where they are usually of a beautiful purple. The margin 

 is finely crenulated around three-fourths of its circumference. The 

 shell is roughly heart-shaped in outline, about three and one-half inches 

 long when full grown, and two and three-quarter inches high. These 

 characters will distinguish it from any other form found upon our 

 coast. The purple color is wanting in young shells, quite variable in 

 amount in others, and is often covered by a thick white glazing in very 

 old ones, while in certain cases it is wanting altogether. 



Of its mode of life, Prof. Verrill says,—" Common on sandy shores^ 

 living chiefly on the sandy and muddy flats, just beyond low-water 

 mark, but is often found on the portion laid bare at low water of spring 



