DESCRIPTION OF FIFTY-TWO SPECIES OF UNIONID^. 49 



nearly in the centre of the cavity of the beaks; cavity of the shell rather deep; 

 cavity of the beaks very small ; nacre white or purple and very iridescent. 



Remarks. — A single mature and several young specimens are before me. In 

 outline it is near to neglectus (nobis), but it is more oblong and not ventricose. 

 The tips of neither of the specimens are perfect enough to observe the character 

 of the undulations. The specimen figured is evidently a female. 



Unio ligatus. pi. 17, fig. 47. 



Testa laevi, ovato-oblonga, sabcompressa, insequilaterali, postice obscure biangulari, antice rotundata; 

 valvulis subcrassis ; natibus prominulis ; epidermide tenebroso-fusca, polita, obsolete radiata, 

 transverse vittata; dentibus cardinalibus parviuseulis, corrugatis et in utroque valvulo duplicibus; 

 lateralibus longis, lamcUatis, corrugatis subcurvisque ; margarita vel alba vel salmonis colore 

 tincta et valde irideseente. 



Shell smooth, ovately oblong, somewhat compressed, inequilateral, obscurely 

 biangular behind, rounded before ; valves rather thick ; beaks rather prominent ; 

 epidermis dark brown, polished, obscurely radiate and transversely banded ; cardi- 

 nal teeth rather small, corrugate and double in both valves ; lateral teeth long, 

 lamellar, corrugate and somewhat curved ; nacre white or salmon colored and very 



iridescent. 



Proc. Acad. Nat. Sci., 1872, p. 15T. 

 Hah. — Irwin's Creek, Mecklenburg Co., and Long Creek, Gaston Co., N. C, 



C. M: Wheatley. 



My cabinet and cabinet of Mr. Wheatley. 

 Diam. -8, Length 1-6, Breadth 2-8 inches. 



Shell smooth, ovately oblong, somewhat compressed, inequilateral, obscurely 

 biangular behind, rounded before; substance of the shell rather thick; beaks 

 rather prominent ; ligament rather long, thin and dark brown ; epidermis dark 

 brown, poHshed, obscurely radiate and transversely banded, with distant marks of 

 growth; umbonial slope rounded; posterior slope subcarinate, narrow elliptical, 

 with obscure impressed lines from the beaks to the posterior margin; cardinal teeth 

 rather small, corrugate, crenulate and double in both valves ; lateral teeth long, 

 lamellar, corrugate and somewhat curved ; anterior cicatrices distinct, large and 

 well impressed ; posterior cicatrices confluent, large and slightly impressed ; dorsal 

 cicatrices small and placed above the centre of the cavity of the beaks ; cavity of 

 the shell shallow and wide ; cavity of the beaks shallow and curved ; nacre white 

 or salmon colored and very iridescent. 



Emaryts. — Specimens of this species were sent to me by Mr. Wheatley, to 

 whom I am obliged for many new and interesting Uniones from North Carolina. 



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