NO. 2116. ANATINAGEA FROM WEST COAST OF AMERICA— BALL. 451 



Length, 15; height, 8; diameter, 1.3; beaks behind the anterior end, 

 3.5 mm. 



Distribution. — ^Type locality, near Ballenas Lagoon, Lower Cali- 

 fornia, in 5 J fathoms. 



Cat. No. 171053, U.S.N.M. 



Carpenter thought this group, which he regarded as a genus, was 



confined to oriental seas, but the discovery of this species adds it to 



the West American fauna. It may be that the supposed specimen 



of C. ceylanica, obtained by Cummg at Muerte Island, West Colombia, 



and referred to by Sowerby and Carpenter, belongs to the present 



species, which has the disk within the pallial line marked by radiating 



lines. 



Subgenus FOVEADENS Dall, 1915. 



Hinge with two diverging teeth in the right valve the posterior 

 longer and higher; an obscure ridge reaching to the front edge of the 

 anterior adductor scar may represent a third tooth; in the left valve 

 are two short teeth close together, a long lamina in front of them 

 carries the resilium on its posterior face; the top of this lamina is 

 grooved and from its anterior edge a deck or sheet of shelly matter 

 unites it with the margin of the valve leaving a hoUow space beneath 

 the deck and between the lamina and the margin. 



Type. — Foveadens panamensis DaU. 



FOVEADENS PANAMENSIS, new species. 



SheU thin, white, compressed, anterior dorsal margin flattened, in 

 the right valve a marked groove below its outer edge ; the disk shghtly 

 concentrically undulate, sculptured with faint incremental lines, 

 anterior area hardly defined; anterior dorsal margin slightly convex, 

 posterior slightly concavely arcuate; left valve with a single liration 

 below the edge of the dorsal margin and close to it; hinge as in the 

 subgeneric diagnosis. Length, 18; height, 11; diameter, 1; beaks 

 behind the anterior end, 4 mm. 



Distribution. — Type locahty, beach at Old Panama, Doctor Mac- 

 Donald. Cat. No. 252276, U.S.N.M. 



Only loose valves were found of this interesting form. 



Subgenus PANDORA sensu stricto. 



PANDORA CISTULA Gould, 1850. 



Distribution. — Patagonia, U. S. Exploring Expedition. Cat. No. 

 5887, U.S.N.M. 



While this species was obtained, according to the original label, 

 somewhere in the eastern part of the Patagonian archipelago, it 

 probably extends its range also to the western part, and so the refer- 

 ence to it here is not out of place. 



