Plate II. 



Trigonia reniforme. 



Fig. la. — Cast of right valve, interior. The palUal line is recognizable, but the cos- 



tation is not well shown in the figure. 

 Fig. 2a. — Dorsal view; anterior end uppermost. Cast of interior. 



Gervillea cf. newcombii. 



Fig. 2. — Cast of interior of left valve. The upper straight edge represents the hinge- 

 line. The rounded ridge extending from end to end is the cast of the 

 body-cavity. 



