SUPPLEMENT TO ISAAC LEA'S PAPER ON UNIONID^. 57 



TJnio strumosus. pi. 19, fig. 55. 



Testa Isevi, rotundata, inflata, insequilaterali, postice obtuse angulata, antice rotundata ; valvulis 

 erassis ; natibus prominulis ; epiderraide tenebroso-fusca vel nigra, eradiata ; dentibus cardinali- 

 bus subgrandibus, rugosis, in utroque valvule duplicibus; lateralibns longis, rugosis curvatisque; 

 margarita alba et iridescente. 



Shell smooth, rounded, inflated, inequilateral, obtusely angular behind, rounded 

 before; valves thick; beaks a little prominent; epidermis dark brown or black, 

 without rays ; cardinal teeth rather large, rugose, double in both valves ; lateral 

 teeth long, rugose and curved ; nacre white and iridescent. 

 Proc. Acad. Nat. Sci., 1873, p. 423. 



Hah.— Yadkin Eiver, North Carolina, C. M. Wheatley. 



My cabinet and cabinet of Mr. Wheatley. 

 Diam. 1, Length 1-7, Breadth 2-6 inches. 



Shell smooth, rounded, inflated, inequilateral, obtusely angular behind, rounded 

 before; substance of the shell thick; beaks a little prominent; ligament large and 

 dark brown ; epidermis dark brown or black, without rays, with distant marks of 

 growth; umbonial slope obtusely angular; posterior slope somewhat raised and 

 narrow elliptical ; cardinal teeth rather large, rugose and double in both valves ; 

 lateral teeth long, lamellar, rugose and curved ; anterior cicatrices distinct, rather 

 large and well impressed ; lateral cicatrices confluent and large ; dorsal cicatrices 

 placed above the centre of the cavity of the beaks ; cavity of the shell rather large 

 and somewhat deep; cavity of the beaks rather deep and obtusely angular; nacre 

 white and iridescent. 



Remarks. — The three specimens before me are all white. One has a slight tint 

 of salmon color. Others may be found purple or deep salmon. Neither of these 

 specimens is in good condition, and the beaks being much eroded there is no 

 indication of the undulations of the tips. In outline it is allied to rotundatus Lam., 

 but cannot be confounded with that species. 



Unio subolivaceus. pi. 20, fig. 56. 



Testa Isevi, oblonga, subcompressa, inEequilaterali, postice obtuse angulari, antice rotundata; valvulis 

 erassis, antice parum crassioribus ; natibus prominulis ; epidermide luteo-olivacea, subnitida, 

 eradiata; dentibus cardinalibus grandis, sulcatis, in utroque valvule duplicibus; lateralibus per- 

 crassis obliquisque ; margarita alba et iridescente. 



Shell smooth, oblong, somewhat compressed, inequilateral, obtusely angular 

 behind and rounded before; valves thick, rather thicker before; beaks slightly 



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