Descriptions of New Fluviatile Shells. 



carinae, of which two central ones are more prominent ; sutures 

 linear ; aperture large, ovate, exhibiting the elevated ridges on 

 the body whorl, as linear, brown bands seen through the sub- 

 stance of the shell ; columella rounded, deeply indented, having 

 a small purple spot below the middle, with a slight sinus at 

 base. 



Length 0.56 inch (14 millim.). Diarn. 0.35 inch (9 millim.). 



Length of aperture 0.28 inch (7 millim.). 



Breadth of do. 0.18 inch (4 millim.). 



Habitat. Alabama. 

 My cabinet. 



Obs. The only specimen I have is somewhat mutilated, but 

 seems nevertheless perfectly distinct ; the only known species 

 with which I can compare it is M. sulcosa Lea, which is a much 

 thinner and more elevated species. The aperture of the pre- 

 sent shell is also proportionally much larger, and the number 

 of whorls less, for, though injured in that part, the rapid dimi- 

 nution of the whorls does not indicate an elevated spire ; the 

 number of raised lines on the body whorl is also less, and 

 they are rather very elevated costcc than strice as in Mr. Lea's 

 species. 



30. Nlelania torulosa. 



Plate III. Fig. 10. 



T. conica, subcrassa, castanea ; spira parum elevata, acuta ; anfr. V-8, 

 supra suturam valde carinatis ; suturis linearibus; apertura late ovata, 

 intiis purpurascente ; columella incurva, in sinum tenuem desinente. 



Shell conic, chestnut colored, rather thick ; spire little ele- 

 vated, acute ; whorls 7-8, strongly carinated a little above the 

 suture ; sutures linear ; aperture not large, broad-ovate, pur- 

 plish within ; columella regularly but not remarkably curved, 

 with a small sinus. 



