PLATE XLTI. 



PLIOCENE AND QL'ATEKNAKY PECTENS. 



[Unless i)ther\viso statuil all ti^iire-v nrv ;i|t[irnxinialel\' mitunil size.] 



Page. 

 Fig. 1. I'fclen [Pccten) excavatus Anton. L. >S. J. U 134 



Exterior of right valve; altitmle (i.") mm. Recent, (xulf of Californiii. (JI. B. ) 

 Fill. 1((. Same specimen as iifr. 1 i;!4 



Exterior of left valve; altitude 57 inin. (M. P.) 

 Flo. 1/). Same specimen as fig. 1 \:i4 



Profile of both valves as viewed from tlic nar. ( M. P.) 

 Fid. 1'. I'eclm {Clitamys) Idtlanritus Conrad. 1>. A 115 



Exterior of riglit valve; altitude 25 mm. Han Pedro formation (Pleistocene), San Pedro, 

 Los Angeles County, Cal. (M. P.) 

 Fici. 2((. Same specimen as lig. '2 115 



Profile of right valve as viewed from the rear, showing comi'xity of typical form. 

 Fio. S. I'ccleii ( ('lilaimjx) Itilliiiiriliix Conrad. 1). A 115 



Exterior of left valve; altitude 27 mm. Same locality as tig. 2. ("SI. I'.) 

 Fiii. 3a. Same specimen as fig. 3 115 



Prolile of left valve as viewed from the rear. (M. P.) 

 Fio. 4. I'lclm {Cldiiviiis) lalidiiriltis Conrad var. iiiiiiiuliiiieris Conrad. 1). A I'M 



Exteror of right valve; altitude 20 mm. San Pedro formation (Pleistocene), Los 

 Cerritos, Los Angeles County, Cal. (M. P.) 

 Fio. 5. I'ciieii (Chlaiiti/x) hiliaii rttiin Conrml var. iiiiiniitiiitirin Vimrud. 1). A 131 



Exterior of left valve; altitude 22 mm. Same locality as fig. 4. ('SI. P.) 

 Fig. 5o. Same specimens as ligs. 4 and 5 131 



Profile of both valves, as viewed from the rear. Note the greater convexity of the left 

 valve as compared with the greater convexity of the right valve in J'erleu s. s. ( M. P. ) 

 Fii;. (i. I'irtcii (Chlaiiii/x) luHauiiliis Conrad var. cn-rHfihtix n. var. Ii. .\. Tyjie 129 



Exterior of right valve; altitude 24 mm. San Pedro formation ( Pleistocene), San Pedro, 

 Los Angeles County, Cal. (M. B. ) 

 Fiii. 7. I'ldrn (Cliliimiix) /(ilidHritiix Ci)i>n\'\ var. (rrritensis n. var. D. A. Cotype 129 



Exterior of left valve; altitude 21 njm. Same locality as fig. (j. (,M. P.) 

 Fig. S. I'irk'ii (''/ilitnii/x) liilidnritiiH Conni] \ar. J'ucicolnx Dall. V. S. N. M. 9(j049 131 



Exterior of right valve; altitude .'it) mm. Recent, on kelp, off Cerros Island, Lower 

 California. (M. P.) 

 Fig. S((. Same specimen as fig. 8 131 



Exterior of left valve. (M. P.) 

 Fiii. 9. I'ciicii {Cliliiii)i/s) lalidiirifns Conrad \ar. iliinxi n. var. 1>. A. Type 130 



FIxterior of right valve; altitude 12 mm., ,< 3. San Pedro I'ormation (lower ])ortion ), 

 Pleistocene, Deadman Island, near San Pedro, Los Angeles County, Cal. (S. ) 



Fig. 9((. Same specimen as fig. 9, natural size 130 



Fig. 10. Pccten (Cltlainys) Idliaurilus Conrad var. delosi n. var. D. A. Cotype 130 



I'jXterior of left valve; altitude 11 mm., X 3. Same locality as fig. 9. (S. ) 

 Fig. 10((. Same S])ecimen as fig. 10, natural size 130 



236 



