206 OSTREID^. 



very convex upper valve. It is generally much distorted, trans- 

 parent, and not so fragile as most species, not scaly. 



Found among oysters. 



See remarks under the following species. 



Anomia squamula, Lin. 



A small, smooth, rounded, or oblong-oval shell, very thin and 

 regular, exhibiting regular concentric lines of growth ; color whit- 

 ish ; edges well defined ; aperture rounded. 



Found attached within old bivalve shells. 



This and the last species, however, are not positively made out. 



