386 CALIFOENIA ACADEMY OF SCIENCES. 



EXPLANATION OF PLATE XIL 



Fig. I. Pecten ( Pecten) denlatus Sawe.v.'&Y. Living shell from Gulf of California. Exterior 



of left or flat valve. Altitude 58 mm.; natural size. 104 



Fig. \a. Same specimen. Outline, showing convexity of right valve; natural size. 104 



Fig. 2. Pecten (Chlamys) laliauritus Conrad. Upper San Pedro series, San Pedro. 



Exterior of left valve. Altitude 23 mm.; xi 3- in 



Fig. 2a. Same specimen. Outline, showing convexity of same valve; XI.3. m 



Fig. 3. Pecten (Pecten) stcarnsii Dali-. Pliocene, San Diego. Exterior of left or flat 



valve. Altitude 65.5 mm.; natural size. 106 



Fig. 4. Pecten (Chlamys) latiauriltis var. vwnotwieris Conrad. Upper San Pedro series, 



San Pedro. Exterior of left valve. Altitude 20.5 mm.; XI.3. 112 



Fig. 4a. Same specimen. Outline, showing convexity of same valve; XI.3. 112 



Fig. 5. Pecten (Pecten) diegensis Dall. Living shell, Monterey. Outline, showing con- 

 vexity of right valve (which is the same as the convexity of the right valve of 

 P. stcarnsii'). Altitude 72 mm.; natural size. 106 



Fig. 6. Pecten ( Chlamys) jordani, sp. nov. Pliocene, Deadman Island. Type specimen, 



exterior of right valve. Altitude 51 mm. ; X0.9. 11 1 



Fig. 7. Same specimen, exterior of left valve; xo.g. 11 1 



Fig. 8. Pecten ( Ch/amys ) latiauritiis var. fragilis, var. nov. Upper San Pedro series, San 



Pedro. Type specimen, exterior of right valve. Altitude 25 mm. ; xi.3- 112 



