494 



CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



EXPLANATION OF PLATES 



Plate I. 



Fig. 1. Oligochiton lioplax Berry, n. sp. Exterior view of head valve 

 from Loc. N. P. 129 [606], in situ. 



Fig. 2. Oligochiton lioplax Berry, n. sp. Same valve after delamina- 

 tion and removal of tegmentum ; same scale as preceding. 



Fig. 3. Oligochiton lioplax Berry, n. sp. Exterior view of median valve 

 from Loc. N. P. 129 [607], in situ; same scale as preceding. 



Fig. 4. Oligochiton lioplax Berry, n. sp. Interior view of right side 

 of same valve, showing radial lines ; same scale as preceding. 



Fig. 5. Oligochiton lioplax Berry, n. sp. Exterior view of tail valve 

 from Loc. N. P. 129, type specimen [608], after removal from matrix; 

 same scale as preceding. 



Fig. 6. Oligochiton lioplax Berry, n. sp. Interior view of same valve; 

 same scale as preceding. 



Fig. 7. Lepidochitona dcntiens (Gould). Exterior view of median 

 valve from Nob Hill Cut, San Pedro, California (Lower San Pedro 

 Pleistocene) [659]. 



Fig. 8. Lepidochitona dcntiens (Gould). Interior view of same valve; 

 same scale as preceding. 



Fig. 9. Lepidochitona dcntiens (Gould). Anterior elevation of same 

 valve ; camera outline. 



Fig. 10. Leptochiton clarki Berry, n. sp. Enlarged view of sculpture 



detail from right side of intermediate valve from Long Wharf Canyon, 



Santa Monica, California (Upper San Pedro Pleistocene) ; type specimen 

 [605]. 



