PANAMIC-PACIFIC PELECYPODA S13 



Subfamily GEJDHNAE Ball, 1902 



Small or minute venerids, usually with a plain or concentrically 

 striated surface. Ovoviviparous, the embryos carried for a period within 

 the perivisceral chamber. 



Genus PSEPHIDIA Dall, 1902 



Type species by original designation, Psephis lordi Baird. [Proposed 

 as a genus to replace Psephis Carpenter, 1864 preoccupied by Psephis 

 Guenee, 1854 {Lepidoptera).'\ 



Shell small, veneriform, trigonal or ovate, inequilateral, with a narrow, 

 feebly defined lunule and no escutcheon. Hinge with three small, simple 

 cardinal teeth in each valve, no laterals. Surface smooth or with faint, con- 

 centric sculpture. Ventral margins smooth or weakly crenulated at the 

 ends. Pallia! sinus distinct, angular. 



Psaphidia cymata Dall 



Psephidia cymata Dall, 1913, Proc. U. S. Nat. Museum, vol. 45, No. 2002, p. 593 Near 

 Cerros Island, Lower California.— Dall, 1921, Bull. U. S. Nat. Museum, No. 

 112, p. 44, pi. 3, fig. 2 Santa Barbara Is., Calif, to the Gulf of California. — 

 Hertlein and Strong, 1948, Zoologica, vol. 33, pt. 4, pp. 193, 194. 



Shell small (length 5 to 6 mm.), white, solid, rounded triangular, with 

 inconspicuous, somewhat anterior beaks, the lunule and escutcheon small 

 and poorly developed. Surface marked with fine, threadlike concentrics, 

 usually not perfectly regular. Periostracum rather coarse and of a yellow 

 color. Pallial sinus small, pointed upward and bluntly rounded at the end, 

 the adductor scars distinct. 



Length 6 mm., height 5.5 mm., diameter 2.5 mm. 



This species is probably not a true member of the Panamic fauna. 

 Range — California southward to the Gulf of California (Dall). 



Extralimital species recorded or described as new species from the 

 Panamic-Pacific Province. 



Antigona fordi Yates. This is a Californian species. 



Ventricota lepidoglypta Dall, 1902. Original described from a specimen in a lot of 

 West Coast species purchased at Acapulco, Mexico, in 1868 by Dall. This is 

 a Caribbean species, now known to be living at Martinique and some other 

 West Atlantic localities. 



Venus apodema Dall, 1902. Described from Humboldt Bay, Gulf of Panama. Arthur 

 Schoot (more likely Humboldt Bay, California), The type specim°n has the 

 appearance of a ballast shell and is probably a worn Ventricola lepidoglypta 

 from the Caribbean. 



Chione obliterata Dall. Also described from Humboldt Bay. Like the preceding it is 

 evidently a ballast shell and seems to be the same as Chione clenchi Pulley, 1952 

 from the Gulf of Mexico, a name which it would replace. 



Chione schotti Dall, 1902. Also from Humboldt Bay. Another ballast shell, probably 

 Venus striatula Da Costa of Europe. 



Also from the same material collected by Arthur Schott at Humboldt 

 Bay is a specimen of Donacilla cornea Poli, a Mediterranean species, USNM 

 6237. 



