PLATE XX. 



Cyhiina {continued). 



Figs. 

 1-5. G. Sedgwicki (Walker). Lower Greensand. (P. 133.) 



1. Potton. The Type. Mr. Walker's Collection, a, right valve; b, dorsal view of 

 both valves. 

 2-5. Upware. Sedgwick Museum. 2, 4, 5, left valves. 3 a, right valve ; 3 b, anterior 

 view of 3 a. 



G. G. obtusa, Keeping. Lower Greensand, Upware. Sedgwick Museum. 

 The Type, a, left valve; />, dorsal view. (P. 133.) 



7-12. G. amenta, Sow. Upper Greensand, Blackdown. (P. 134.) 



7. British Museum, L 17066. Eight valve. 



8. British Museum, L 17066. Left valve. 



9, 10. Sedgwick Museum. Left valves. 10 b, dorsal view of 10 a. 

 11. British Museum, L 17066. Left valve. 

 12 a. British Museum, L 17066. Right valve. 12 b, hinge, x 1|. 



13. C. tealbiensis, Woods. Tealby Limestone, Claxby. British Museum, No. 



49985. a, left valve, X |; 1>, dorsal view of both valves, X f. 

 (P. 13G). 



14. C. sp. Speeton Clay, Speeton. Sedgwick Museum. Left valve. (P. 



137.) 



15, 1G. G. anglica, Woods. Lower Greensand (Crackers), Atherfield. Sedg- 

 wick Museum. Left valves. (P. 137.) 



