PLATE XIX. 



■AGE. 



Fig. 1. ASTARTELLA 341 



1«. Kight valve. 



lb. A profile view of dorsal side of .same, attached to a piece of rock so as to hide the hinge. 



Fig. 2. ASTARTELLA VARICA 341 



Left valve. S"atuial size. 



Fig. 3. AsTARTELLA Newberryi 340 



Left valve. 



Fig. 4. YoLDiA Stevensoni 335 



4ft. Left. \ iilve, natural size, .showing the fine, very regular surface .stria'. 

 4b. Dorsal view of .same. 



Fig. 5. YOLDIA CARBONARIA 336 



View of right xalve. 



Fig. 6. Allokisma costata 344 



da. View of left valve. 

 66. Dor.sal view of same. 



Fig. 7. POSIDONOMYA FRACTA 333 



7a. View of right valve. .. 



76. Left valve of this. or. po.s.sibly, of another species. 



Fig. 8. Cypricardina ? carbonakia 342 



8a. Cast of a left valve, magnified to show the impressions of the hinge-teeth. 

 86. View of the cast of the interior of a right valve. Natural size. 



Fig. 9. Macrodon obsoletus 334 



Oast of interior of right valve, showing impressions of posterior hinge-t«eth. 



Fig. 10. Pleurophorus tropidophorus 338 



lOa. Cast of the exterior of right valve. 



106. Cast of the interior of left valve, showing impressions of posterior lateral teeth. 



Fig. 11. SOLENOMYA?? ANODONTOIDES 339 



The two valves opened, and spread out in the matrix. 



Fig. 12. Placunopsis recticarmnalis 331 



An internal cast, apparently of the left or upper valve, showing its very peculiar surface 

 markings. 



Fig. 13. AvicuLOPECTEN ? Hertzeri 330 



13a. Left valve. 



136. Kight valve. 



13c. A larger left valve. 



Fig. 14. ISpirifer opimus 329 



14a. View of vential valve. 

 146. View of dorsal valve of same. 

 14c. Anterior view of same. 



lid. Posterior view of same, showing area, foramen, etc. 



14e. A ventral view of another individual, more extended on the hinge, and with mesial sinus 

 narrower. 



