166 AXEL A. OLSSON 



Aeqnipecten (Leptopecten) blolleyi (H-ertleln and Strong) Plate 22, figures 3, 3a 



Pecten (Leptopecten) vclero biolleyi Hertlein and Strong, 1946, Zoologica, vol. 31, pt. 

 2, pp. 60, 61, pi. 1, fig. 6 Port Parker, Costa Rica.— Hertlein and Strong, 

 1955, Bull. Amer. Mus. Nat. Hist., vol. 107, art. 2, p. 181. 



Shell small and thin, sculptured with about 12 or 13, rather high, 

 sharply triangular ribs which are separated by considerably wider inter- 

 spaces. When fresh, both ribs and interspaces are covered with a dense 

 fringe of imbricated lamellae but become smooth when worn. The lateral 

 ribs are generally larger than the others although sometimes every third 

 rib may be somewhat accentuated. Color white and brown arranged roughly 

 in concentric bands. Length of the type specimen, 6.9 mm., height 6.6 mm. 



This subspecies is said to differ from the typical form in having fewer 

 ribs, 12 as compared to 14 to 16. 



Range — Costa Rica to Panama. Costa Rica: Port Parker. Panama: 

 Guayabo Chiquito, Panama (all Hertlein and Strong). Ecuador: Esmer- 

 aldas. 



Genus CHLAJTTS Roeding, 1798 



Type species by subsequent designation, Herrmannsen, 1847, C. cin- 

 nabarina Roeding (=C islandica Miiller). 



Shell large or small, thin or of moderate weight, the left valve some- 

 what more inflated than the right, otherwise alike in shape and sculpture. 

 Surface sculptured most often by primary and secondary radial ribs, often 

 rendered coarsely scabrous by intersecting concentrics. The auricles or ears 

 in the typical species are strongly unequal, the anterior ear much larger, 

 that of the right valve cut into by a deep, byssal notch. 



The typical species of Chlamys comprise high, rounded, and somewhat 

 oblique, subequivalve shells, with unequal ears and a large, deep, 

 byssal notch. Surface with strong primary ribs and smaller interpolated 

 ribs which increase in number with growth. The genus has been subdivided 

 into many subgenera and sections. 



Chlamys (Chlamys) lowei Hertlein 



Pecten (Chlamys) loivei Hertlein, 1935, Proc. California Acad. Sci., ser. 4, vol. 21, No. 

 25, p. 308, pi. 19, figs. 1, 2, 7, 8 Carmen Island, Gulf of California, in 20 

 fathoms. — Hertlein and Strong, 1946, Zoologica, vol. 31, pt. 2, p. 57. 



Shell small, the right valve with a deep byssal notch under the anterior 

 ear. Surface sculptured with 20 to 22 rounded, triangular, and spinose ribs. 

 A spinose secondary rlblet is present in each interspace. Color is white or 

 grey flecked with brown or some specimens may be partly orange or reddish 

 brown. The largest specimens attain a height of about 18.5 mm. 



Range — Gulf of California and Clarion Island to Panama and the Gala- 

 pagos. For locality stations consult Hertlein and Strong. 



Chlamys (Chlamys) zeteki Hertlein 



Pecten digitatus Hinds, 1844, Zool. Voy. Sulphur, Moll., pt. 3, p. 61, pi. 17, fig. 2 "Bay 

 of Guayaquil". — Reeve, 1853, Conch. Icon., vol. 8, Pecten, pi. 35, fig. 172. — 



