PLATE II. 



Fig. 

 1. 



Cyprideis torosa, p. 21. 



a. Left valve, outside. 



b. Right valve, outside. 



c. Perfect, dorsal aspect. 



d. Perfect, posterior aspect. 



e. Left valve, outside 



f. Right valve, outside . 

 y. Right valve, hinge-line 

 h. Left valve, hinge-line . 

 i. Part of surface 



2. Cytherideis trigonalis, p. 47. 



a. Perfect, left valve upwards 



b. Left valve, dorsal view 



c. Right valve, inside 



d. Left valve, anterior hinge 



e. Left valve, posterior hinge 



f. Left valve, inside 



y. Part of inside of right valve 

 h. Part of surface of valve 



Old 



X 



25 



X 



25 



X 



25 



X 



25 



X 



25 



X 



25 



X 



50 



X 



50 



x 150 



Grays. 





x 12 





x 12 





x 12 



. 



X 50 





X 50 





x 12 [ 



showing lucid spots 



x 30 





xl50-^ 



Grays. 



Clacton. 



Grays. 



3. Cytherideis tuberculata, p. 47. 



a. Left valve, inside (broken) 



b. Left valve, hinge-line 



c. Left valve, dorsal view 



d. Perfect, dorsal view 



e. Left valve, outside 



f. Left valve, inside 



Cytheridea pinyuis, p. 4 3. 



a. Perfect, right valve upwards 



b. Perfect, posterior aspect 



c. Perfect, dorsal aspect (young or male) 



d. Perfect, dorsal aspect (old or female) 



e. Right valve, inside 

 f. Left valve, inside 

 y. Portion of surface of 4 c, with papillae and fine pits 

 h. Portion of surface of 4 b, with pits 



Cy there punctata, p. 24. 



a. Left valve, outside (broken at posterior end, old) 



b. Right valve, outside 



c. Perfect, dorsal aspect 



d. Perfect, anterior aspect 



e. Left valve, inside (young) 

 f. Left valve, inside 

 y. Right valve, inside 

 h. Part of surface of valve 



X 



25 



X 



25 



X 



25 



X 



25 



X 



25 



. X 



25 



X 



25 



X 



25 



X 



25 



X 



25 



X 



25 



X 



25 



X 



150 



X 



150 



Crag. 



/ Crag. 



x 25 



x 25 



x 25 



X 25 



x 25 



x 25 



x 25 

 x!50 



Crag. 



