

PLATE 75. 



Fiu'. 1. 690. 10. TkI.LINOMYA? EQUILATERA. ( Pag. 330.) 



1 a, b. Similar views of two specimens, sliowing a slight diflcrence in form, iirobably fUie 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. Kight and loft valve, and profile view of the specimen. 



Fig. 3. 692. 12. Avict'i.a sui!Rf.ct.\. (Pag. 331.) 



Left valve of .J. subrect -. 



Fig. 4, o. 693. 13. Avicula seccrifokmis. (Pag. 331.) 



4. Cast of the left valve. .J 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 lim^f&rmis. (Pag. 332.) 



C a. Cast of the interior of the right valve, in whieli the plications are fjuitc distinct .ind angular. 



(j b. Interior of the right valve of another .<;|)ecinicn, in whicli the spaces between the plications arc nearly flat. 



6 c. Portion enlarged. 



