Anculosae of the Alabama River Drainage 39 



rounded, though occasional opercula of the creek forms have the apex acute. 

 The left margin is usually curved, but sometimes straight or nearly so; the 

 right margin is always broadly curved, usually thin and torn; the basal 

 margin rounded when entire. The polar point is on the left margin close to 

 the base, the spiral lines closely coiled, the edges of the whorls within the 

 operculum virtually disappearing after the first one and three-quarters 

 whorls. 



Measnrcuicnts of the shells : 



Altitude Diameter 



20 mm. 13^ mm. Cahaba River, Lily Shoals, Bibb County 



17V2 1354 



16 iiy2 



15'/^ 12 



1SV2 II 



14^ 10^/ 



Pratt's Ferry, 



Ti^ gYz Little Cahaba River 



16 iij^ Coosa River, Wetumpka 



155^ 12 



151^ 1054 " 



13!/$ gYz Canoe Creek, St. Clair County 



15 10^ Ohatchee Creek, Calhoun County 



14^ 10 



14 9M 



15 ID Kelly's Creek, St. Clair County 

 13 9 Yellowleaf Creek, Shelby County 



1414 loy, Waxahatchee Creek, Shelby-Chilton Counties 



13 10 



Anculosa mimica H. H. Smith, new species 



Fig. 24 



Shell: Rather heavy, rough, in form like the subglobose forms of A. ampla Anth. 

 Growth lines coarse, revolving lines apparently absent. There are four heavy folds 

 and one light fold at the shoulder upon which are narrow nodules or tubercles sug- 

 gestive of the sculpture of Paludomiis corinata Reeve. The nodules are strongest 

 near the peristome. Color of epidermis citrine, broken by three well-marked bands, 

 these appearing in the aperture as six very dark, continuous bands. Columella strong, 

 ridge-like at the center, flattened on the outer surface from the middle to the base, 

 outer edge projecting slight^ over the body whorl. The columella is nearly pure 

 white and has two small blotches of purple on the inner edge. Peristome flaring as 

 in ampla, thin but firm; thickened about i mm. within the aperture. Aperture broadly 

 ovate. 



Operculum: Similar to that of A. ampla. Nucleus pitted, located upon the left 

 margin near the base. Whorls three. The operculum illustrated is slightly deformed 

 at the left margin close to the nucleus. 



Mcasureinents: Altitude, 12% mm.; diameter, gy^ mm. Aperture — altitude, 6j^ 

 mm. ; diameter, 51^ mm. 



Type locality: Little Cahaba Creek, three miles east of Piper, Bibb County, Ala- 

 bama. Herbert H. Smith, collector, June, 1916. 



Type in the Museum of Zoology, University of Michigan ; paratypes in that 

 museum and the Alabama Museum of Natural History. 



