PLATE 75. 
Fig. 1. 690. 10. Tellinomya? equilatera. (Pag. 330.) 
la, b. Similar views of two specimens, showing a slight difference in form, probably due to pressure. 
1 c. Cardinal view of fig 1 a. 
1 d. View of the posterior slope, showing the groove in each valve. 
Fig. 2. 691. 11. Avicula? -. (Pag. 331.) 
2 a, b, c. Right and left valve, and profile view of the specimen. 
Fig. 3. 692. 12. Avicula subrecta. (Pag. 331.) 
Left valve of A. subrecti. 
Fig. 4, 5. 693. 13. Avicula securiformis. (Pag. 331.) 
4. Cast of the left valve. , 5 a. The interior of the left valve of a young shell. 
5 b. The interior of the left valve of a full grown individual. 
Fig. 6. 694. 14. Avicula limjeformis. (Pag. 332.) 
6 a. Cast of the interior of the right valve, in which the plications are quite distinct and angular. 
6 b. Interior of the right valve of another specimen, in which the spaces between the plications are nearly flat. 
6 c. Portion enlarged. 
