PLATE XXIII. 

 C ypeina (continued) . 



Figs. 



1, 2. G. (Venilicardia) lineolata (Sow.). Upper Greensand, Blackdown. 

 Sedgwick Museum. Right valves. 2, a short form. (P. 143.) 



3. G. (Venilicardia) truncata (Sow.). Upper Greensand, Blackdown. The 



Type. Bristol Museum, a, left valve; b, dorsal view of the same. 

 (P. 145.) 



4. G. (Venilicardia) truncata ? (Sow). Upper Greensand, Blackdown. Exeter 



Museum. Left valve. Probably an elongate variety of G. truncata. 

 (P. 145.) 



5. C. (Venilicardia) truncata ? (Sow.). Upper Greensand, Blackdown. 



Sedgwick Museum. a, right valve; b, hinge. Probably a short 

 variety of G. truncata. (P. 145.) 



6-9. G. quadrata, d'Orb. Gault, Folkestone, except fig. 6. (P. 146.) 



6. Upper Greensand, Warminster. Sedgwick Museum. Internal cast. Right 



valve. 



7. Sedgwick Museum, a, left valve ; b, dorsal view. 



8. British Museum, L 0183. Right valve, decorticated. 



9. Sedgwick Museum, a, left valve ; b, dorsal view. 



Genus — Trapezium, v. Muhlfeldt. 

 10,11. T. ? arcadiforme (Keep.). Lower Greensand, Up ware. (P. 148.) 



10. The Type. Sedgwick Museum, a, right valve ; 6, dorsal view. 



11. Mr. "Walker's Collection. Anterior view. 



12-15. T. ? squamosum, (Keep.). Lower Greensand, Upware. Sedgwick Museum, 

 except fig. 14. (P. 148.) 



12. Left valve. 



1 3 a, right valve ; b, dorsal view. 



14. Mr. Walker's Collection, a, left valve, x 11- ; b, interior of same, X 1§. 



15 a, right valve ; b, dorsal view. 



16. T. ? sp. Lower Greensand, Upware. Sedgwick Museum, a, left valve; 

 b, dorsal view. (P. 149.) 



17-19. T. trapezoidale (Rom.). Chalk Rock, Cuckhamsley. Sedgwick Museum. 

 (P. 149.) 



17 a, left valve ; b, dorsal view. 



18 a, right valve ; b, anterior view. 

 1!». Ritrht valve. 





