DESCRIPTION OF FIFTY-TWO SPECIES OF UNIONID^. 21 



nent, minutely undulate at the tips; epidermis dark brown, shining, and very 

 much radiate; cardinal teeth small, much compressed and double in both valves; 

 lateral teeth long and somewhat curved; nacre purple or salmon colored and 



iridescent. 



Proc. Acad. Nat. Sci., 1871, p. 193. 

 Hah. — Santee Canal, So. Car., Dr. Foreman ; and Oconee River, Geo., Major J. 



Le Conte. 



My cabinet. 

 •Diam. -9, Length 1-4, Breadth 2-5 inches. 



Shell smooth, somewhat oblong, rather inflated, very inequilateral, rounded 

 before, obtusely biangular behind ; substance of the shell a little thick ; beaks a 

 little prominent, minutely undulate at the tips ; ligament rather long and dark 

 brown ; epidermis dark brown, shining and very much rayed, with very distant 

 marks of growth ; umbonial slope inflated and rounded ; posterior slope narrow 

 elliptical and with two slightly impressed lines from the beaks to the posterior 

 margin; cardinal teeth small, compressed, double in both valves; lateral teeth long 

 and somewhat curved ; anterior cicatrices distinct and well impressed ; posterior 

 cicatrices large, confluent and moderately impressed ; dorsal cicatrices placed over 

 the centre of the cavity of the beaks ; cavity of the shell rather deep and wide ; 

 cavity of the beaks shallow and rounded ; nacre purplish, tinted with salmon and 

 iridescent. 



Remarks. — This species is closely allied to confertus (nobis) and lugubris (nobis), 

 and belongs to the great complanatus group. It is rather more compressed than 

 either of them, and is not quite so elongate. In color of epidermis and rays it 

 resembles both. Three specimens have been in my collection for many years, and 

 they were placed with a doubt as a variety of lugubris. I no longer hesitate to 

 believe it to be a distinct species. 



Unio radiolus. pi. 6, fig. 18. 



Testa leevi, elliptica, subinflata, valde insequilaterali, antice rotunda, postice obtuse angulata; vaWulis 

 crassiusculis; natibus prominulis, fere terminalibus; epidermide brunnea, valde radiata; dentibus 

 cardinalibus parvis, subcompressis crenulatisque ; lateralibus longis, lamellatis subcurvisque ; 

 margarita alba et iridescente. 



Shell smooth, elliptical, somewhat inflated, very inequilateral, round before, 

 obtusely angular behind ; valves somewhat thick ; beaks a little prominent, nearly 

 terminal; epidermis brownish, very much radiate; cardinal teeth small, somewhat 

 compressed and crenulate; lateral teeth long, lamellar and somewhat curved; 



nacre white and iridescent. 



6 



