PLATE II. 



Old 



Fig. 

 I. Cyprideis torosa, p. 21. 



a. Left valve, outside. 



b. Riglit valve, outside. 



c. Perfect, dorsal aspect. 



d. Perfect, posterior aspect. 



e. Left valve, outside 



f. Right valve, outside . 



g. Right valve, hinge-line 

 h. Left valve, hinge-line . 

 I. Part of surface 



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 

 /. Left valve, inside 

 g. Part of inside of right valve, showing lucid spots 

 h. Part of surface of valve 



X 2.5 



~j 



X 25 





X 2.5 





X 25 





X 25 



Grays. 



X 25 





X 50 





X 50 





xl50- 





X 12 



Grays. 



x 12 



Clacton 



X 12 \ 





X 50 





X 50 

 X 12 

 X 30 

 xl50 



; Grays. 



Cythei-ideis 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 

 /. Left valve, inside 



X 25 



x 25 



X 25 



X 25 



Crag. 



4. Cytheridea pinguis, 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 valvCf inside 

 /. Left valve, inside 



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



h. Portion of surface of 4 b, with pits 



5. Cythere 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) 

 /. 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 



ts . X 



150 



X 



150^ 



X 



25 



. X 



25 



X 



25 



X 



25 



X 



25 



. X 



25 



. X 



25 



. X 



50 



Crae. 



