PLATE XVII. 



Terebratula harmonia 

 Pig. 1-4. Profile, dorsal, front and ventral view of a specimen. Page 154 



Productella subaculeata, var. cataracta. 



Fig. 5-8. Dorsal, ventral and front and transverse view of a speci- 

 men. Page 69 

 Fig. 9. Ventral view of a specimen, showing almost perfect spines. 



Strophodonta inequistriata. 



Fig. 10. Ventral valve of a specimen. Page 145 



Fig. 11. An enlargement of a portion of the surface, showing inter- 

 calated striae. 



Bellerophon leda. 



Fig. 12. 13. Profile and side view of a specimen. Page 158 



Tropidoleptus carinatus. 



Fig. 14, 15. Dorsal and ventral view of a specimen. Page 46 



Chonetes yandelliana. 



Fig. 16-18. Ventral and dorsal view and transverse section of speci- 

 men. Page 68 

 Fig. 19. Dorsal view of a larger specimen. 



Strophodonta profunda. 



Fig. 20. Ventral valve of a specimen. Page 148 



Fig. 21. An enlargement of a portion of the surface showing radiat- 

 ing striae. 



