PLATE XXI. 



Cypkina (rontinncd). 



Figs. 



1. C. anglica, Wood^^. Lower Greensand (Crackers), Atherfield. Sedgwick 



Museum. ((, right valve; J>, dor8al view. (P. lo7). 



2. 0. claxbieims, Woods. Claxljy Ironstone, Benniwortli Haven. Sedgwick 



Museum. Left valve. (P. 135.) 



3. f. sp. Tcalby Limestone, Claxby. Sedgwick Museum. Lvh valve, 



X I (P. 13G.) 



1—7. C. {Vcnilicanlla) jjrutensa, Woods. Lower Greensand, Atherfield. See 

 also Text-figures 20, 21. (P. 137.) 



4. Pe;H(/-1)eil. Soilt,'wick Muse'iiiii. a. left valve, X I ; h, dorsal view, X j. 



5. Perna-\)nA. Museum of Practical Geolo^^y, No. lG74-i. Hinge of left valve. 



6. PernaAynX. British Museum, L 432. Hiuge of right valve, x J. 



7. Crackers. British Museum, L 6304. A small specimen. Right valve. 



8, 9. G. Sowerhiji, d'Orb. See also Text-figure 22. (P. 139.) 



8. Hythe Beds, Hythe. Sedgwick Museum. Internal cast i>f right valve. 



9. Lower Greensand, between Atherfield and Blackgaug. York Museum. Left 



valve. 



