COMPLETE GRAU : PECTINIDAE OF THE EASTERN PACIFIC 145 



Geochronological range: ?Pliocene, Pleistocene, Recent. 



Bathy?netric range: 5 to 200 fathoms. 



Ecological data : Usually found on or swimming above the following 

 varieties of bottom: shale, rock, gravel, gray sand, green sand, mud; 

 associated with coralline, nullipores, kelp, sponge. 



Hancock Expeditions Collecting Stations: 

 WESTERN LOWER CALIFORNIA: 7 stations, all in vicinity of 



Cedros Island; 16-49 fathoms, rock, sand. 

 SOUTHERN CALIFORNIA AND SANTA BARBARA IS- 

 LANDS: 27 stations; 15-150 fathoms, gravel, sand, mud. 



Subgenus PATINOPEGTEN Dall 1898 



Patinopecten Dall, 1898, p. 695. [Proposed as a section of Chlamys.] 

 Type species: Pectcn cauriniis Gould, 1850, p. 345; type locality: 

 Port Townsend, Washington [then Oregon Territory]. 

 Blanckenhornia von Teppner, 1922, p. 260. [Proposed as a subgenus of 

 Philippia von Teppner, 1922, p. 221 ; see synonymy of Pecten, this 

 paper.] Type species: Pecten (Patinopecten) lohri Hertlein, 1928, 

 p. 93; type locality: Pliocene of California. [New name for Pecten 

 (Patinopecten) oweni Arnold, 1906, p. 63, pi. 8, figs. 1, la, lb; 

 non Pecten oweni de Gregorio, 1884b, p. 133.] 

 Original diagnosis: Valves with small ribs, flat on the right valve 

 and sometimes dichotomous ; smaller and more rounded on the left 

 valve ; concentric sculpture inconspicuous ; radial striae absent or obso- 

 lete ; ears subequal ; valves nearly equilateral. 



Additional diagnostic notes: Adult shells are very large. Both valves 

 are quite compressed, the right being slightly deeper. 



Remarks: Blanckenhornia was based on medial sulcations of the ribs, 

 a feature not of supraspecific significance. 



This subgenus contains only two living species: P. caurinus Gould 

 and P. caurinus yessoensis (Jay). Both attain the largest size of any 

 living Pectinidae, the maximum reported for the typical being a length 

 of 288 mm and height of 198 mm, that for the subspecies being a length 

 of 214 mm and height of 180 mm. 



Pecten (Patinopecten) caurinus Gould 1850 



Plate 54 



Pecten caurinus Gould, 1850, p. 345. "Hab. Port Townsend, Admiralty 

 Inlet, Oregon" [Washington].— Gould, 1852, p. 458; 1856, pi. 42, 

 figs. 569, 569a, 569b. 



