102 Descriptions of Neiv Fluviatile Shells. 



Obs. — In form, like M. Duttoniana Lea, but without any of 

 the ornamental decorations of that species. The nodules are not 

 so distinct, appearing more like interrupted folds. The striae 

 on the body whorl are not uniformly distributed, but about the 

 middle there is a plain surface or ground, which becomes more 

 decidedly a furrow on the penultimate" whorl. 



21. Mela ni a cm'Yilabris. 



Plate III. Fig. 1, a, b. 



T. conica, subcrassa, corneo-virente ; spira elevata; anfr. 7—8, convexis, 

 subangulatis, ultimo utriuque angulato, in medio late constricto ; suturis 

 irregulariter valde impressis; apertura irregulan, intus albida; labro 

 profunda retrorsum sinuato; columella valde incurva, subfoveata, in 

 sinum profundum producta. 



Shell conical, smooth, rather thick, greenish horn-color ; spire 

 elevated ; whorls 7-8, convex or subangulated ; body whorl 

 angulated, with a depression broad but not deep ; sutures 

 deeply and irregularly impressed ; aperture very irregular, by 

 the twisted columella and the sinuous curving of the outer lip, 

 within whitish ; outer lip deeply and singularly curved, so as 

 to give this part of the shell almost a pleurotomose character ; 

 columella very much curved and indented, leaving a small 

 umbilical indentation, and having a distinct sinus at base. 



Length 0.72 inch (19 millim.). Diam. 0.30 inch (8 millim.). 



Length of aperture 0.25 inch (6 millim.). 



Breadth of do. 0.15 inch (4 millim.). 



Habitat — Tennessee. 



My cabinet. Cab. Coleman Sellers, Cincinnati, O. 



Obs. — May be compared with If. ehgantula in general form, 

 but its peculiarly curved outer lip will at once distinguish it 

 from all others. 



