PLATE XIX. 



PAGE. 

 Fig. 1. ASTARTELLA ." , 341 



la. Rij^ht valve. 



1&. 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 



Lel't A'alve. Natural size. 



Fig. 3. ASTARTELLA Newberryi 340 



Left valve. 



Fig. 4. YoLDiA Stevensoni 335 



4a. Left valve, natural size, showing the liiie, very regular surface strias. 

 4&. Dorsal view of same. 



Fig. 5. YOLDIA CARBONARIA 336 



Ticw of right valve. 



Fig, 6. * Allorisma costata 344 



fia. View of left valve. 

 6&. Dorsal view of same. 



Fig. 7. POSIDONOMYA PRACTA 333 



la. View of right valve. 



lb. Left valve of this, av, possibly, of another species. 



Fig. 8, Cypricakdina ? carbonaria 342 



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

 8&. View of the cast of the interior of a right valve. Natural size. 



Fig. 9. Macrodon obsoletus 334 



Cast of interior of right valve, showing impressions of posterior hinge-teeth. 



Fig. iO. Pleurophorits tropidophorus 338 



lOa. Cast of t^e exterior of right valve. 



10b. CasD of the interior of lett 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 recticardinalis 331 



An iiitei-nal cast, apparently of the left oi- uppei- valve, showing its very peculiar surihce 

 markings. 



Fig. 13. AvicuLOPECTEN ? Hbrtzeri 330 



13a. Left valve. 



VSb. Kight valve. 



Vic. A larger left valve. 



Fig. 14. Spirifer opimus 32i> 



14a. View of ventral valve. 

 14i). View of dorsal valve of same, 

 14c. Anterior view of same. 



i\d. Pohteiior view of same, showing area* foramen, etc. 



I4c, A ventral view of another individual, more extended on the hinge, and with mesial slims 

 uairuwer. 



