88 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 23 



Pectcn (Pecten) hastntus Sowerby. Grant & Gale, 1931 \ex parte], p. 

 166, pi. 11, figs. 6a, 6b. [P. hericius Gould in synonj'my.] Living: 

 Alaska to San Diego. [Upper Miocene, Pliocene and Pleistocene 

 records also given.] 

 Chlamys hericus [sic] Gould. Morris, 1952, p. 17, pi. 12, fig. 2; pi. 41, 

 fig. 2. Alaska to San Diego, California. [Specific name also mis- 

 spelled on descriptions of plates.] 

 Chlamys hastatus hericius Gould. Abbott, 1954, p. 364, pi. 34, fig. k. 

 Holotype: U.S. National Museum. 



Type locality : Juan de Fuca Strait, Washington. Gould's reference 

 to Oregon was correct in 1850, for at that time Oregon comprised the 

 present states of Oregon and Washington and part of British Columbia. 

 Original description : T. rotundato-triangularis, equilateralis, equi- 

 valvis; valvis convexus, sub-tumidis; valva superior rosea, lineis exilibus 

 concentricis exasperata, et costis ad 24 angulatis, alternis majoribus et 

 spinis erectis fornicatis insculpta; valva inferior pallidior colore satura- 

 tiori zonata, costis sub-equalibus spiniferis armata ; natibus acutis, promi- 

 nentibus; auribus obliquis valde inequalibus radiatim squamoso-striatis ; 

 intus porcellana ; marginibus crenulatis, rosaceis. Long. 4^^ ; alt. 1 ^ ; 

 lat. 4% poll. 



Additional description : Adult shell averaging about 70 millimeters 

 in altitude, not quite as long as high, both valves compressed, equilateral 

 (except for ears), which are decidedly unequal; margins finely serrate; 

 sides markedly concave above; umbo acute. Right valve with 9 or 10 

 pairs of spiny fasciculi, the middle rib of each fascicule being the most 

 prominent ; interspaces about as wide as the fasciculi, and ornamented by 

 several more or less spiny riblets; spaces between the riblets of the 

 fasciculi and large interspaces channeled and ornamented by fine imbri- 

 cating incremental lines, but free from any reticulations whatever ; hinge 

 line a little over one-half the length of the disk ; anterior ear about two 

 and one-half times longer than the posterior, ornamented by imbricating 

 concentric lines, and above the notch by several subequal spiny riblets ; 

 byssal notch wide and deep ; posterior ear small, and ornamented by 

 numerous fine spiny riblets. Left valve with about 9 or 10 elevated 

 fasciculi, the middle rib of each fascicule being quite prominently spinose ; 

 the spaces between the major fasciculi each occupied by a minor fascicule 

 of more or less scaly riblets ; interspaces between the riblets channeled 

 and with imbricating incremental sculpture ; ears sculptured as in right 

 valve except that the riblets are smaller and more numerous on the 

 anterior ear. Hinge weakly developed. Color pink to greenish [sic], left 



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