no" DESCRIPTIONS OF 



above the cavity of the beaks ; cavity of the shell rather deep and somewhat wide ; 

 cavity of the beaks rather deep and angular ; nacre light salmon color and iridescent. 

 Remarks. — This species in outline is very near to Unto Bun-oughianm, (nobis), 

 from Rio Parana, but differs in the color of the epidermis, being yellowish olive and 

 not dark bottle green ; both have radiating folds on the beaks, but those of Bur- 

 roucjManus are larger, fewer and not so long. They differ in the cardinal teeth, the 

 South American species being compressed and oblique, and the nacre being silver 

 white without any tint of salmon color. In outline it differs from Wheatleyanus, 

 (nobis), in being more oblique, in not having a carina, in having smaller folds on the 

 beaks, in having a white nacre, and in the teeth not being so oblique or compressed. 

 In the color of the epidermis they are both very much alike. In the Wynegumjaensis 

 the beaks are furnished with numerous, beautiful folds directed towards the basal 

 margin, the central ones having a zigzag inflection with acute angles. 



Unio consobrinus. pi. 4-5, fig. 152. 



Testa laevi, elliptica, subiniiata, inaequilaterali, postice? obtus^ angulata, antice rotundata ; valvulis sub- 

 tenuibus, antic6 paulisper crassiusculis ; natibus prominulis ; epidermide micante, tenebroso-fusca, 

 eradiatfi ; dentibus cardinalibus parvis, crenulatis, eompressis, obliqui.s, in valvulam dextram duplici- 

 bus ; lateralibus luiigis, lamellatis subcurvisque ; margarita salmonis colore tincta et valde iridesccnte. 



Shell smooth, elliptical, somewhat inflated, inequilateral, obtusely angular behind, 

 rounded before ; valves rather thin, a little thickened before ; beaks a little promi- 

 nent ; epidermis shining, dark brown, without rays ; cardinal teeth small, crenulate, 

 compressed, double in the right valve ; lateral teeth long, lamellar and somewhat 

 curved ; nacre salmon colored and very iridescent. 



rni<, rw,sn/,riiins, Lea. I^roc. Acad. Nat. Sci.. JS.'jQ, p. 3;51. • 



Bab.— ChhvA. C. M. Wheatley. 



My cabinet and cabinet of Mr. Wheatley. 

 Diam. -9. Length l-.^. Breadth 24 inches. 



Shell smooth, elliptical, somewhat inflated, inequilateral, obtussely angular behind 

 and rounded before ; substance of the shell rather thin, slightly thickened before; 

 beaks a little prominent ; ligament rather long, thin and light brown ; epidermis 

 shining, minutely striate, without rays, dark brown, except at the beaks and at the 

 basal margin where there is a broad border of light brown ; umbonial slope somewhat 

 raised and roimded ; posterior slope slightly raised, rather broad, with two indistinct 

 lines from the beaks to the posterior margin in both valves ; cardinal teeth small, 

 crenulate, compressed, double in the rigJit valve and single in the left; lateral teeth 

 long, lamellar and somewhat curved, double in the left and single in the right valve ; 

 anterior cicatrices distinct and moderately impressed ; posterior cicatrices confluent and 

 very .slightly impressed ; dorsal cicatrice.'? in a row across the centre of the cavity of 



