EXPLANATION OF PLATE II. 



OSTREA VlRGINIANA Gmel. (p. 27). 



Figs. 1, 2. Inner and outer surfaces of a narrow form. Upper valve. 

 3, 4. Similar views of a curved form of upper valve. 

 5, 6. Interior and profile views of a lower valve of the ordinary form. 

 7. Copy of Mr. Gabb's figure of 0. Mauricensis from vol. 4, Jour. Acad. Nat. Sci., PI. 67. 



Pecten Madisonius Say (p. 30). 



Fig. 8. View of a fragment from a large shell. 



(See other figures on PI. iv.) 



148 



