^Q7 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Plate V. 



Fig. 1. Mopalia ciliata (Sowerby). Exterior view of head valve from 

 Chiton Bed, Point Fermin, California (Lower San Pedro Pleistocene) 

 [1036]. 



Fig. 2. Mopalia ciliata (Sowerby). Interior view of same valve; same 

 scale as preceding. 



Fig. 3. Mopalia ciliata (Sowerby). Profile of same valve,; camera 

 outline. 



Fig. 4. Mopalia ciliata (Sowerby). Exterior view of median valve, 

 probably from Deadman Island, San Pedro, California (Pleistocene) [676]. 



Fig. 5. Mopalia ciliata (Sowerby). Interior view of same valve; same 

 scale as preceding. 



Fig. 6. Mopalia ciliata (Sowerby). Anterior elevation of same valve; 

 camera outline. 



Fig. 7. Mopalia ciliata (Sowerby). Exterior view of tail valve from 

 Chiton Bed, Point Fermin, California (Lower San Pedro Pleistocene) 

 [1038] ; same scale as Fig. 1. 



Fig. 8. Mopalia ciliata (Sowerby). Interior view of same valve; same 

 scale as preceding. 



Fig. 9. Mopalia ciliata (Sowerby). Profile of same valve; camera 

 outline. 



Fig. 10. Mopalia acuta (Carpenter). Exterior view of median valve 

 from Long Wharf Canyon, Santa Monica, California (Upper San Pedro 

 Pleistocene) [762]. 



Fig. 11. Mopalia acuta (Carpenter). Interior view of same valve ; same 

 scale as preceding. 



