170 PROCEEDINGS OF THE ACADEMY OF 



This species is allied to E. carolinense, and differs from it by a more depressed 

 and flattened head, a more truncated snout which, as usual, protrudes beyond 

 the lower jaw. The body itself is likewise more depressed, and the limbs 

 assume a slender appearance. 



The head is continuous with the body, and constitutes about the third of their 

 combined length. The cleft of the mouth does not extend as far back as in 

 E. carolinense, since it corresponds to a perpendicular line drawn behind the 

 pupil. The longitudinal diameter of the eye is equal to the distance between 

 the orbit and the nostril. The interocular space, measured across the anterior 

 rim of the orbits, is greater than the rostral space from the orbits forwards. 

 The symphysis of the lower jaw presents the same structure as in the species 

 just alluded to. 



The skin is perfectly smooth throughout in all the specimens which we have 

 examined; they were collected in April, and are, no doubt, liable to assume a 

 rougher appearance during the hotter and more dry season of the year. 



The ground color of the upper region of the head, body and limbs, is of a 

 light olivaceous brown tint, anteriorly uniform, posteriorly besprinkled with 

 small black spots or dots especially over the coccyx and thighs. A whitish 

 tint pervades uniformly throughout the inferior regions. 



Specimens of this species were procured in Texas, by Capt. John Pope. 



Descriptions of Twelve New Species of TJNIONES, from Georgia. 



BY ISAAC LEA. 



Unio Baldwinensis. Testa oblonga, compressa, ad latere planulata, inequi- 

 laterali, postice biangulata; valvulis subcrassis, antice paulisper crassioribus ; 

 natibus prominulis ; epidermide vel luteola. vel fusca, eradiata; dentibus cardi- 

 nalibus parviusculis, subcompressis, subelevatis, crenulatis, in utroque valvule 

 subduplicibus ; lateralibus praelongis lamellatis subrectisque; margarita vel 

 alba, vel salmonis colore tincta et valde iridescente. 



Hab. Carter's Creek, Baldwin Co., Georgia. J. Postell. 



Unio vikidans. Testa lrevi, oblonga, compressa, ad latere planulata, postice 

 biangulata, antice rotundata, valde inequilaterali ; valvulis subtenuibus ; 

 natibus prominulis, ad apices undulatis ; epidermide fusco-viridi, striata, ob- 

 solete radiata; dentibus cardinalibus parvis, striatis, crenulatis; lateralibus 

 praelongis, lamellatis subrectisque; margarita vel alba, vel salmonia, ssepe 

 purpurea et valde iridescente. 



Hab. Near Columbus, Georgia. G. Hallenbeck. 



Unio Hallenbeckii. Testa, laevi, suboblonga, compress^, ad latere pla.iulata, 

 valde inaequilaterali, postice subbiangulari, antice oblique rotundata; valvulis 

 subcrassis ; natibus prominulis, ad apices crebre et concentrice undulatis ; 

 epidermide rufo-fusca, micante, obsolete radiata; dentibus cardinalibus sub- 

 grandibus, compressis, erectis, crenulatis, in utroque valvulo duplicibus ; 

 lateralibus longis, crassis rectisque ; margarita vel purpurea vel salmonis 

 colore tincta et valde iridescente. 



Hab. Flat Rock Creek, and Four Mile Creek, near Columbus, Georgia. G. 

 Hallenbeck, and Bishop Elliott. 



Unio salebkosus. Testa laevi, oblonga, subcompressa, ad latere planulata, 

 postice biangulata, antice subtruncata, valde inaequilaterali ; valvulis subcrassis, 

 antice paulisper crassioribus; natibus subprominentibus, ad apices crebre et 

 concentrice undulatis ; epidermide vel rufo-fusca vel luteo-fusca et valde 

 striata: dentibus cardinalibus subgrandibus, striatis, subelevatis crenulatisque ; 

 lateralibus praelongis subcurvisque ; margarita vel albil vel salmonia, rare 

 purpurea et iridescente. 



[June, 



