Ancui.osae of the; Alabama River Drainage 19 



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aperture. Growth lines coarse. The left margin is nearly straight, the 

 right margin curved and serrated regularly, the base broadly rounded, ser- 

 rated. The nucleus is sunken, the spiral lines loosely coiled, whorls three. 

 The serrations begin at about one and one-half whorls, and usually can be 

 observed even after the horny material of the operculum fills the interstices 

 between them. 



Measurements of shells: 



Altitude Diameter 



igV2 mm. 13 mm. Three Island Shoals, Talladega County 



18 iiVi 



21V2 14^ Fort William Shoals, " " 



2oy2 izVi 



I.J 14 



j8 12 



18 14 Peckerwood Shoals, " " 



20 13^ Weduska Shoals, Shelby County 



18 13 The Bar, Chilton County 



20j^ 13^ Near mouth Yellowleaf Creek, Chilton County 



191^ 14 



17 12^ 



20^ 13 Butting Ram Shoals, Coosa County 



The species is confined to the Coosa River, appearing first at Three 

 Island Shoals and reaching the limit of its distribution at Wetumpka, Mr. 

 Smith's collection of foremani at this locality consisting of just one speci- 

 men. Judging by the numbers collected, the shallows near the mouth of 

 Yellowleaf Creek, Chilton County, are the most flourishing places in the 

 river for this most interesting form. 



Anculosa clipeata H. H, Smith, new species 

 Fig. 8 



Shell: Conic, of moderate thickness, body whorl slightly flattened, the base 

 rounded. Growth lines fine, tending to wear smooth below the periphery; crossed in 

 places just below the suture by a few discontinuous, waving striae. Apex eroded. 

 Suture impressed. Three or four low nodules appear on the shoulder, marking where 

 growth has been made over the deposit of shell material at the top of columella. 

 Aperture ovate, yellowish white. Peristome sharp-edged, firm, curving outward just 

 below the suture, a little sinuous toward the base. Columella pearl-white, rounded, 

 a little flattened on the outer edge near the center, heavy at the top. The ground 

 color of the epidermis is raw sienna of the Ridgeway color standards, with twelve 

 interrupted lines of dark coloring matter, these showing up very sharply within the 

 aperture. 



Operculum: Oval, thick, leathery, measuring 6 mm. by 3^ mm. Apex acute. 

 Left margin not so curved as the right margin, this margin being thickened, smooth- 

 edged. The basal margin is broadly rounded. The nucleus is very small, slightly 

 sunken, located about iH mm. from the left margin and in the lowermost third of 

 the operculum. Whorls three. 



Measurements of shell: Altitude, 15^ mm.; diameter, 11^ mm. Aperture — • 

 altitude, 6% mm. ; diameter, 5 mm. 



Type locality: Coosa River, Fort William Shoals, Talladega County, Alabama. 

 Collected by Herbert H. Smith, June, 1914. 



