Bull. U. S. F. C. 1890. Lamellibranchiate Mollusks. (To face page 436.) 



1 



Plate LXXXVII. 



Fig.54 



Fig.55 



^ , ,_ , , !§<S O U 



i g, .-%."%■ O: 



Fig. 53 



Fig.63 



Kellogg del. 



