THE NAUTILUS. / 



radial striae, are in texture and shape like the typical shells 

 from the Black Warrior. While this smoother form quite 

 probably represents a local race worthy of recognition, as it has 

 not been found by more recent collectors and no exact localities 

 for it are known, it hardly seems advisable to do more than to 

 call attention to its peculiarities until more definite information 

 as to its precise range can be had. 



Rhodacmea cahawbexsis, n. sp. PI. I, figs. 4-6. 



Ancylus filosus Walker, Xaut,, XVIII, 1904, p. 76, pi. vi, 

 figs. 1-6. 



Shell elevated, obtusely conical, broad oval, somewhat wider 

 behind the apex than before it; apex obtuse, slightl)^ behind 

 the longitudinal centre of the shell, scarcely, if at all, turned 

 towaid the right side, apical sculpture entirely eroded in all 

 specimens seen; yellow horn color slightly tinged with gi'een, 

 apex rose color; anterior slope convex toward the apex, straighter 

 below; posterior slope nearly rectilinear; lateral slopes shghtly 

 convex, the left being more oblique than the right; lines of 

 growth strong and irregular, slightly rippled by radial lines, 

 which sometimes become obsolete radial striae. 



Length 4.5; width 3.5; alt. 2.5 mm. 



Types, (no. 43453 Coll. Walker), from the Cahawba River, 

 Gurnee, Shelby Co., Ala., collected by H. H. Smith. Cotypes 

 in the collections of the Acad, of Xat. Science, Philadelphia, 

 George H. Clapp and John B. Henderson. Also from Cahatchee 

 Creek and Yellowleaf Creek, Shelby Co., Ala. The single 

 specimen from the latter locality shows subobsolete radial stria- 

 tion ver}' much like the '' Coosa River " specimens in the Lewis 

 collection which in my former paper I referred to Jilosa, but 

 which I now think belong to this species. The fact that the 

 heavily striated jilosa is quite characteristic of the Coosa, where 

 this species has not been found by Mr. Smith in his extensive 

 collections, makes me doubt whether the Lewis shells really 

 did come from the Coosa itself. Unfortunately no exact locality 

 is given by Lewis and the question must remain undetermined. 



This species is more closely related to the elatior Anth. of the 

 Tennessee drainage than to any of the known species of the 



