[103] 

 13. Dsedalochila Ariadne, Pfeiffer. 



Plate ]0, figures 15, 16, 18. 



Shell depressed, subdiscoidal, finely ribbed above, smooth 

 beneath, upper surface a little convex ; whorls 5, with slightly 

 depressed suture; body Avhorl deflected, much constricted and 

 scrobiculate behind the aperture ; aperture small, lip thick, 

 much expanded, its extremities joined by a callus forming an 

 irregular, flexuose, V-shaped tooth, its point extending far within 

 the aperture ; lip Avith two stout basal folds converging within, 

 while behind them is a perpendicular broad laminae almost en- 

 tirely closing the mouth ; base convex, showing more than one 

 whorl with a rounded umbilical groove terminating in a minute 

 oblique central perforation. Transparent white, shining. 



Diam. 12, height 5 mill. 



Tamaulipas, Mexico, 



tf t Outer teeth tubercular^ swelled, placed behind the parietal 



tooth, 



X Shell, smooth below. 



14- Daedalochila Dorfeuilliana, Lea. 



Plate 10, figures 20, 21. 



Obtusely conical above and slightly angulated on . the peri- 

 phery ; whorls 6, with well impressed suture, ribbed, smoother 

 below, deflected and constricted behind the aperture but without 

 scrobiculations. Aperture lunar, the extremities of the lip 

 joined by a callus forming a quadrate tooth on the outer whorl, 

 far within, behind the parietal tooth, are two rounded tubercles, 

 one superior and one basal, of nearly equal size ; base showing 

 IJ whorls and a minute perforation. Whitish. 



Diam. 7*5, height 4 mill. 



Kentucky and Tennessee. Texas? l';. 



14 



