NATURAL SCIENCES OF PHILADELPHIA. 171 



Unio tknebricds. Testa IsEvi, elliptica, subinflata, postice obtuse angulata, 

 inaequilaterali ; valvulis tenuibus, antice crassioribus; natibus prominulis ; 

 epidermide tcnebroso-fusca, obsolete radiate ; dentibus cardinalibus parvis, 

 valde crenulatis, in utroque valvulo duplicibus ; lateralibus lamellatis cur- 

 visque ; margarita vel purpurefl, vel salmonis colore tinctii et iridescente. 



Hab. Etowah River, Georgia. Bishop Elliott and Rev. G. White. 



Unio rufus. Testa laevi, transversii, valde compressS., ad latere planulata, 

 postice obtuse angulata, valde inaequilaterali ; valvulis subcrassis ; natibus 

 prominulis, accuminatis ; epidermide rufo-fuscfi, eradiata ; dentibus cardinali- 

 bus parvis, obtuso-conicis crenulatisque ; lateralibus sublongis, subcrassis 

 curvisque ; margarita coeruleo-alba et iridescente. 



Hah. Etowah River, Cass County, Georgia. Bishop Elliott. 



Unio modicus. Testfi, laevi, obliqua, subinflata, postice subbiangulata, valde 

 inaequilaterali ; valvulis crassis, antice crassioribus ; natibus subprominentibus, 

 ad apices rugoso-undulatis ; epidermide tenebroso-fuscii, eradiata ; dentibus 

 cardinalibus subgrandibus crenulatisque ; lateralibus curtis, crassis subcur- 

 visque ; margarita vel alba vel pallido-salmonia et iridescente. 



Hab. Chattahoochee River, near Columbus, Georgia. Bishop Elliott. 



Unio denigbatus. Testa laevi, elliptica, subinflata, ad latere planulata, in- 

 aequilaterali ; valvulis subtenuibus, antice crassioribus; natibus prominulis; 

 epidermide nigricante, eradiata et micante ; dentibus cardinalibus parvis, 

 pyramidatis crenulatisque; lateralibus sublongis, lamellatis subcurvisque ; 

 margarita vel purpurea vel salmonis colore tincta et iridescente. 



Hab. Streams near Columbus, Georgia. Bishop Elliott. 



Unio fumatus. Testa laevi, elliptica, compressa, postice biangulata, in- 

 aequilaterali ; valvulis subtenuibus ; natibus subprominentibus ; epidermide 

 tenebroso-fuliginosa et eradiata; dentibus cardinalibus parviusculis crenu- 

 latisque ; lateralibus sublongis, subcrassis subrectisque ; margarita purpures- 

 cente et valde iridescente. 



Hab. Chattahoochee River, near Columbus, Georgia. Bishop Elliott. 

 Hospaliga Creek, Alabama. Dr. Neisler. 



Unio porpurellus. Testa laevi, oblonga, subinflata, ad latere planulata, 

 postice biangulata, valde inaequilaterali ; valvulis crassiusculis ; natibus promi- 

 nulis ; epidermide tenebroso-fusca et postice obsolete eradiata; dentibus 

 cardinalibus parviusculis, crenulatis, in utroque valvulo subduplicibus ; 

 lateralibus prEelongis, lamellatis subcurvisque ; margarita purpurea et valde 

 iridescente. 



Hab. Flint River, near Albany, Georgia. Bishop Elliott. 



Unio penicillatus. Testa postice plicata, elliptica, subinflata, postice sub- 

 biangulata, inaequilaterali ; valvulis crassiusculis, antice crassioribus ; natibus 

 subprominentibus ; epidermide luteola, radiis penicillatis indutis, polita ; 

 dentibus cardinalibus crassiusculis, crenulatis, subpyramidatis ; lateralibus 

 sublongis, subcrassis subrectisque ; margarita vel alba vel rosed vel salmonis 

 colore tincta et valde iridescente. 



Hab. Chattahoochee, near Columbus, Georgia. Dr. Boykin. Near Atlanta. 

 Bishop Elliott. Flint River, near Albany, Georgia. Bishop Elliott and Rev. G. 

 White. 



Unio Plantii. Testi laevi, regnlariter elliptica, valde compressa, inaequi- 

 laterali ; valvulis subcrassis, antice crassioribus ; natibus prominulis ; epi- 

 dermide tenebroso-castanea, eradiata ; dentibus cardinalibus parviusculis, 

 subdepressis, obtuso-conicis crenulatisque ; lateralibus praelongis, subcrassis 

 curvisque ; margarita salmonis colore tincta et valde iridescente. 



Hab. Flint River, near Macon, Georgia. I. C. Plant. 



1857.] 



