p r. A T K X X X 1 \' . 



I'LIOCK.NF, AND 1'1.KIST( K^EN'K ri'XTKNS. 



[rnlt'ss otlicrwisu stiittMl all liKures an- iipproxiniati-ly luitiirHl size] 



Page 



Fk;. 1. J'rcleii ( Fecti'ii) mi/ilivi n. sp. C. A. S. C'utypt' 100 



Exterior of .sliahtlv imix'ri'crt li'ft viilve: altitmk' 74 iiim. Pleistnrene, Ventura ("ovintv, 

 Cal. (S.) ' 



Fui. -. I'ecli'ti ( Pi'fleii) iinhiiri/i n. sp. ( '. S. 31. 11. Cntype fl4 



Exterior of left valve; altitude o6 iniii. I'liocene, ruente Hills, Los Angeles County, 

 t'al. (S.) 



Fig. 2(1. Same specimen a.s fij;. 2 94 



I'rolile of left valve as viewcil from the rear. (M. P. ) 



Fii;. .S. I'crleii [Pdlinopcrlen) piirlKiinaoists n. sp. I). A. Type 105 



Exterior of somewhat imi)erfeet left valve; altitude 12.S mm. Purisinia formation ( low er 

 Pliocene), north of the mouth of Pe.scadero Creek, San Mateo County, Cal. (JI. P. i 



Fio. 4. I'er-Irn ( PaliiKipivtni ) tiirnrri n. sp. L. S. J. F. Cotype lOti 



Exterior of u imrtinn of the di.>ik of a left valve. Pliocene. Tomales Bay, Marin County, 

 Cal. 



212 



