Anculosae of the Alabama River Drainage 



43 



bands. Seven different arrangements of the bands were observed, the com- 

 monest consisting of a single thin band at the top of the aperture, with two 

 bands at the base. Many of the specimens had bands in the epidermis with- 

 out showing any in the aperture. In one specimen only were the bands 

 coalesced so as to involve the whole shell. In this case the aperture was 

 purple-colored throughout. The columellae of nearly all the shells were 

 tinged with brown or red from top to center and the columella of one indivi- 

 dual was tinged with purple nearly to the base. 



No shell with uneroded spire was found in this lot from Valley Creek. 

 Sucli parts of apices as remain indicate the nuclear whorls are smooth 

 and loosely coiled, the whorls immediately following being without carinae. 

 The largest number of whorls counted was four. 



There is a strong resemblance between this shell and the creek and small 

 river forms of A. praerosa Say of the Tennessee drainage. Also it is close 

 to A. plicata Conrad. A smooth specimen of plicata from the Forks of the 

 Black Warrior River, when compared with sniithi, was flatter of whorls, 

 angulated at the periphery rather than rounded, the columella proportionally 

 not so heavy. A specimen of praerosa from Flint Creek, Alabama, a Ten- 

 nessee River tributary, was slightly more conic, broad of base instead of 

 regularly rounded, the lip having the characteristic curve of praerosa instead 

 of the straightness of snilthi. AH three specimens when placed together, 

 while easily distinguishable, yet showed a striking general resemblance. The 

 inclination is to assume that the species under discussion represents a con- 

 necting link between the Tennessee Anculosae and those of the Black War- 

 rior. But there is need first of an anatomical understanding of the three 

 species and perhaps of the geological history of the western Alabama stream. 



Measurements of paratypcs: 



Anculosa showaltcrii Lea 

 Fig. 19 



Anculosa shozvalterii Lea, Proc. Acad. Nat. Sci., Phila., XII, p. 93, March, i860. 



Anculotus sulcosus Anth., Reeve Monog. Anculotus, t. 6, f. 44, April, 1861. 



This species appears to be confined to the Fort William and Peckerwood 

 shoals of the Coosa River. Judging from the material collected by Dr. 

 Scho waiter and Mr. Smith, it is not nearly as numerous in individuals as 

 many other members of the genus. 



The shozvalterii which Lea described were "much ribbed . . .with seven 

 transverse ribs . . . outer lip much expanded and very much crenulate.'^ 

 Mr. Smith found and identified smooth forms of the species, corresponding 

 to the smooth forms of the usually heavily sculptured A. griffithiana Lea. 



