PLATE LX. 



Os'i'RKA {continued) . 

 Fios. 

 1—15. 0. Boucheroni, Coq. Upper Chalk. (P. 391.) 



1. Zone of Actiitocamax quaclralus, Wield. Mr. Brydoue's Collection. Left 

 valve. 16, posterior view. 

 2-4. Zone of Marsu^jites tediidinaflus, Brigbtou. 2, 3, Brighton Museum. 

 4, British Museum, No. L 11795. Left valves. 36, posterior view of 3<i. 



5. Uintacrimis band, Thauet coast. Dr. Howe's Collection, u, left valve ; h, 



right valve ; c, anterior view. 



6. Zone of Marsupites tesludinarhts, Brighton. Brighton Museum, o, left 



valve; h. jiostorior view; c, right valve. 



7. Zone of Micrasler cor-aiKjuinum, Loam Pit Hill, Lewisham. Sedgwick 



Museum. Left valve. 

 8, 9. Zme of Micraster cor-aiujuumm, Gravesend. 8, Museum of Practical 

 Geology, No. 2-5977. 9, Ssdgwick Museum. Left valves; 81, posterior 

 view of 8(1. 

 10—13. Uinfacrinus baud, Thanet coast. Dr. Howe's Collection. lOa, right valve 

 and margin of left valve ; lOi, posterior view of lOrt. 11, left valve with 

 large surface of attachment ; h, posterior view. 12, left valve. 13o, right 

 valve; 136, anterior view of both valves showing large surface of attach- 

 ment . 



14. Zone of Micraster cor-amjninum, Loam Pit Hill, Lewisham. Sedgwick 



Museum. Left valve. 



15. Uintacrinug band, Devizes Koad, Salisbury. Dr. Blackmore's Collection. 



Left valve. I, posterior view. 



10 — 19. 0. laimtii, Nilss. Zone of 0. Janata, Triraiiigliam. Mr. R. M. Brydone's 

 Collection. Left valves. (P. 393.) 



