52 



OBSERVATIONS. 



This singular sliell approaches the genus Ancu lo- 

 tus, in form, but the aperture is that of a Melania. I 

 found it adhering to logs in the Tennessee river, at 

 Florence, where it is abundant. My friend, William 

 Hodgson, jr. found it also in the Holston river, in 

 Tennessee. 



MELANIA PYRENELLA. 



Plate YlW.—Fig. 5. 



DESCRIPTION. 



Shell elevated, with flattened whorls, having- an 

 obsolete spiral line on each; suture impressed; body 

 whorl angulated; angle defined by a prominent line; 

 base hardly convex; labrum angulated near the cen- 

 tre; aperture patulous; columella obtusely rounded 

 at the base. 



OBSERVATIONS. 



Inhabits streams in North Alabama. The aper- 

 ture is remarkably patulous and the labrum i)ro- 

 foundly angulated. 



MELANIA B I T ^^ N I A T A . 



Plate YllL—Fig. 6. 



DESCRIPTION. 



Shell conic, with convex whorls; spire short; one 



