COMPLETE GRAU : PECTINIDAE OF THE EASTERN PACIFIC 79 



disk. Anterior auricle large and with moderately deep byssal notch; 10 

 to 12 small riblets with nearly as many intercalaries, all imbricated. 

 Posterior auricle small, hinge margin tapered as in right valve; 10 to 

 15 fine imbricated riblets. Interior glossy white or yellow-white; margin 

 delicately fluted. External color ranging through shades of red, pink, 

 lavender, purple, orange and yellow; right valve much paler than left; 

 occasional specimens mottled, others all white. 



Remarks : It is unfortunate that the specific name hindsii, by which 

 this familiar species has been known for nearly a hundred years, must 

 now become a synonym. However, in Opinion 456, 1957, the Inter- 

 national Commission ruled that Martyn's often-disputed "Universal 

 Conchologist" was not consistently binomial and rejected it, making all 

 the names published therein unavailable; thus rubidus Hinds is now 

 valid for this species, having priority over hindsii Carpenter. 



Geographical range'. Bering Sea to Monterey, California. Also 

 Pacific coast of Japan, as far south as 42° N. 



Geochronological range: Pliocene, Pleistocene, Recent. 



Bathymetric range: Just below low tide to 100 fathoms, possibly 

 deeper. 



Ecological data: Usually found off rocky shores. Shell usually 

 encased in one of two species of symbiotic sponge: most often Ectyodoryx 

 (formerly Myxilla) parasitica (Lambe), but occasionally Mycale ad- 

 herens Lambe. Both species are said to live only on Chlamys rubida, 

 C. rubida jordani, C. hastata, C. hastata hericia and C. hastata puget- 

 ensis, and to be the only species of sponge so restricted. Large barnacles, 

 up to 25 or 30 mm in altitude, are often attached. 



Chlamys rubida jordani (Arnold) 1903 

 Plate 25 



Pecten (Chlamys) jordani Arnold, 1903, p. Ill, pi. 12, figs. 6, 7. "Rare 

 in Pliocene {emend.: Pleistocene] of Deadman Island and lower 

 San Pedro series of Deadman Island. Found also in Pliocene of 

 Packard's Hill and Pleistocene of bath-house, Santa Barbara." 



Pecten kincaidi Oldroyd, 1920, p. 135, pi. 4, figs. 3, 4. ". . . off San 

 Juan Island, Washington, in 25 fathoms." 



Pecten (Chlamys) hindsii kincaidi Oldroyd. Dall, 1921, p. 18. Puget 

 Sound. — Oldroyd, 1924a, p. 53, pi. 12, figs. 1, 2. [Type locality 

 given.]— Oldroyd, 1924b, p. 17, pi. 9, figs. 3, 4. [Type locality 

 given.] 



