PANAMIC-PACIFIC PELECYPODA 455 



Pandora (Pandorella) cornnta C. B. Adams Plate 81, figures 7, 7a 



Pandora cornuta C. B. Adams, 1852, Ann. Lyceum Nat. Hist. New York, vol. 5, pp. 



519, 547, No. 498 Panama. 

 Clidiophora acutedentata (vice C. B. Adams), Carpenter, 1864, Proc. Zool. Soc. London, 



p. 598, No. 5. Replacement name. Reprinted as Smith. Misc. Coll., No. 252, p. 227. 

 Kennerlyia convcxa Dall, 1915, Proc. U.S. Nat. Museum, vol. 49, p. 449 Ballenas Lagoon, 



Lower California. 

 Pandora (Kennerlia) convexa (Dall), Hertlein and Strong, 1946, Zoologica, vol. 31, pt. 



3, p. 97, pi. 1, fig. 5. 



Shell subovate, inequilateral, more or less depressed, the anterior side 

 shorter, rounded, the posterior side wider, obtusely angled at the end. 

 Surface smooth, not divided by a transverse line but with an angle or double 

 carina which overlies the internal posterior lamina and runs from the beak 

 to the posterior end a short distance below the hinge margin. 



Length to about 21 mm. 



This species was described as P. cornuta, based on a somewhat damaged 

 specimen having a subcircular break at the posterior end forming two 

 horns, suggesting the name. The holotype is herewith figured. As the name 

 ''cornuta" seemed inappropriate to Carpenter, he suggested "acutedejitata" 

 as a replacement. Pandora convexa Dall, from its figure as given by Hert- 

 lein and Strong, is thought to represent the same species. 



Range — Lower California to Panama. Panama: Panama. 



Pandora (Pandorella) rhypis Pilsbry and Lowe Plate 81, figure 6 



Pandora (Kennerlia) rhypls Pilsbry and Lowe, 1932, Proc. Acad. Nat. Sci. Philadelphia, 

 vol. 84, p. 105, pi. 16, figs. 8-11. 



The shell is thin, short and high, with a weakly convex left and flat 

 right valve; white. Upper margin is concave behind the beaks; basal margin 

 strongly convex in the middle and posteriorly; anterior third contracted, 

 rounded in front. Sculpture of many narrow radiating riblets on the posterior 

 two-thirds, much weaker in the right valve. Anterior third with lines of 

 growth only. There is also some very weak, coarse, concentric corrugation 

 of both valves. Teeth rather well developed but thin. 



Length 24.5 mm., height 20.7 mm., diameter 4.0 mm. 



Length 24.5 mm., height 19.3 mm., diameter 3.7 mm. (Pilsbry and 

 Lowe, 1932.) 



This species was described from La Union, Gulf of Fonseca, El Salvador. 

 As the species may eventually be found to occur further south the original 

 description and figures have been included here. 



Range — El Salvador. El Salvador: La Union. 



Subgenus CLIDIOPHORA Carpenter, 1864 

 Type species by original designation, Clidiophora claviculata Carpenter 

 (= Pandora arcuata Sowerby). West Mexico. 



Shell usually sickle-shaped, its dorsal side deeply impressed or concave, 

 its posterior end pointed and with a small, open gap. The right valve has 

 three crural laminae, the anterior one elongated, narrow, extending to the 

 front side of the adductor scar; the posterior lamina is also long and narrow, 

 distinct from the elevated edge of the dorsal margin; in the left valve, the 

 anterior lamina is similar to that of the right valve and like it extends 



