NEW UNIONIDiE OF THE UNITED STATES. 73 



Unio Hartmanianus. PI. 8, fig. 222. 



Testa lsevi, oblique triangulari, crassa, turaida, posticc subbiangulari, inaequilaterali ; valvulis percrassis, 

 antice crassioribus ; natibus valde* elevatis, crassis; epiderniide tenebroso-fusca, postice luteola, eradiata; 

 dentibus cardinalibus subgrandibus, erectis, couipressis, corrugatis, in utroque valvule- duplicibus ; 

 lateralibus brevibus, percrassis, obliquis corrugatisque ; margarita argeutea et iridescente. 



Shell smooth, obliquely triangular, thick, swollen, somewhat biangular behind ; 

 valves very thick, thicker before; beaks very much raised, thick; epidermis dark 

 brown, yellowish behind, eradiate ; cardinal teeth rather large, erect, compressed, cor- 

 rugate, double in both valves ; lateral teeth very thick, oblique and corrugate ; nacre 

 silver white and iridescent. 



Proc. Acad. Nat. Sci. 1860, p. 307. 



Hob. — Coosa River, Wetumpka, Alabama. E. R. Showalter, M. D. 



My cabinet, and cabinets of Dr. Hartman and Dr. Showalter. 

 Diam. -1, Length 1-3, Breadth 1-5 inch. 



Shell smooth, obliquely triangular, thick, swollen, subbiangular behind ; substance 

 of the shell very thick, thicker before ; beaks very much raised and thick ; ligament 

 thick and short; epidermis dark brown, yellowish behind, without rays, shining 

 towards the beaks, striate below, and with rather distant marks of growth ; umbonial 

 slope raised and very obtusely angular ; posterior slope broad, flattened, yellowish, 

 with a slight broad furrow from the beaks to the posterior margin; cardinal teeth 

 rather large, erect, compressed, corrugate, double in both valves ; lateral teeth very 

 thick, oblique, corrugate ; anterior cicatrices distinct, rather small, but well 

 impressed ; posterior cicatrices distinct and very well impressed ; dorsal cicatrices 

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

 and rounded ; cavity of the beaks shallow and obtusely angular ; nacre silver white 

 and iridescent. 



Remarks. — Two specimens are before me, nearly of the same size. It is very 

 near to fulgidus (nobis), but is a rather larger species, and not so shining. It belongs 

 to that group of which solidus (nobis) may be considered the type. The lateral teeth 

 are thick and short, and that of the right valve is disposed to be double. I owe the 

 possession of one of the two specimens to W. D. Hartman, M. D., after whom I have 

 great pleasure in naming it. They were sent to him by Dr. Showalter. A larger 

 specimen of this species, or very closely allied, was received many 3'ears since from 

 President Estabrook, taken by him in Clinch River, Tennessee. A specimen about 

 one-third grown has very obscui'e rays on the middle of the disk. 



Unio Showalterii. PI. 8, fig. 223. 



Testa lsevi, subrotunda, crassii, sublenticulari, ajquilaterali ; valvulis crassis, antice crassioribus; natibus ele- 

 vatis, tumidis; epidcriuidc tenebroso-fusca, obsolete radiata; dentibus cardinalibus crassis, erectis, 



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