60 SUPPLEMENT TO ISAAC LEA'S PAPER ON TJNIONID^. 



growth ; unibonial slope very slightly raised and obtusely angular ; posterior slope 

 carinate, narrow elliptical, with two green rays in each valve; cardinal teeth some- 

 what thick, corrugate and double in both valves; lateral teeth long, thick and some- 

 what curved; anterior cicatrices distinct, rather small and well impressed; posterior 

 cicatrices confluent, rather large and slightly impressed ; dorsal cicatrices placed 

 nearly in the centre of the cavity of the beaks; cavity of the shell shallow; cavity 

 of the beaks very shallow and rounded; nacre pale purple or salmon and iridescent. 

 Remarks. — I have had several specimens of this species in my possession for some 

 years. Only one, which is figured, seems to be full grown. It is closely allied to 

 Abbevillensis (nobis) and I have had doubts of its being more than a variety, but 

 the specimens subsequently received have satisfied me as to its being distinct. 

 While nearly of the outline of Abbevillensis it diff"ers in not being so yellow in the 

 epidermis, and in being usually covered with green capillary rays. It is devoid of 

 the strong marks of growth which are so remarkable in that species. None of 

 the specimens had perfect beaks — therefore the undulations are not known. 



Unio infulgens. pi. 21, fig. 59. 



Testa Iffivi, suboblonga, inflata, inequilateral], postice subbiangulari, antice rotundata; valvulis crassis, 

 antice parum crassioribus; natibus prominulis; epidermide nitida, polita, eradiata ; dentibus car- 

 dinalibus subgrandibus, sulcatis et in utroque valvule duplicibus ; lateralibus longis, crassis sub- 

 rectisque ; margarita salraonis colore tincta et valde iridescente. 



Shell smooth, suboblong, inflated, inequilateral, subbiangular behind, rounded 

 before; valves thick, rather thicker before; beaks slightly prominent; epidermis 

 bright, polished and without rays ; cardinal teeth rather large, sulcate and double 

 in both valves ; lateral teeth long, thick and nearly straight ; nacre salmon colored 



and very iridescent. 



Proc. Acad. Nat. Sci., 1873, p. 422. 



lZ-a6._Stewart's Pond, Union Co., North Carolina, C. M. Wheatley. 



My. cabinet and cabinet of Mr. Wheatley. 

 Diam. 1-3, Length 2, Breadth 3-4 inches. 



Shell smooth, suboblong, inflated, inequilateral, subbiangular behind and rounded 

 before; substance of the shell thick, rather thicker before; beaks slightly promi- 

 nent ; ligament large, thick and dark brown ; epidermis bright, polished, without 

 rays and with rather distant marks of growth ; umbonial slope somewhat raised 

 and obtusely angular ; posterior slope carinate, with a -broad slightly impressed 

 groove from the beaks to the posterior margin; cardinal teeth rather large, sulcate 

 and double in both valves ; lateral teeth long, thick, slightly corrugate and nearly 



