55 
GLYCIMERIS, Lam. 
Gen. Char. Equal-valved, transverse, thick, ga- 
ping at both sides ; epidermis thick, extend- 
ing beyond the edge of the shell; hinge-line 
thick, toothless ; fulcra large, tumid ; ligament 
external ; muscular impressions two ; impres- 
sion of the attachment of the mantle deep, 
broad, rugged, with hardly any sinus. 
A Genus related to Panopcea , and according to some, to 
Solen, but distinguished from both by the absence of teeth 
in the hinge, and the want of a sinus in the mantle : from 
Solen it also differs in having more equal and rounded 
sides. It is related to the Myarice in having a thick pro- 
jecting epidermis, which leaves the impressions of its 
wrinkles upon the shell. The foot of the animal as well 
as the length of its tubes must be however very different 
from those parts in the Myarice , as well as in the above- 
mentioned genera. It is remarkable that the umbones are 
often eroded. The recent species inhabit the Northern 
Ocean. 
