THE NAUTILUS. 139 



Only a single adult specimen was found. But quite a number of 

 half-grown individuals occurred. This species differs from all the 

 others known from the Coosa, except S. georgianus, in the solid 

 shell, heavy columellar callus, thickened lip and in the inflation of 

 the upper part of the body whorl. In these respects it resembles S. 

 georgiamts, but differs in size and in being imperforate, lacking the 

 axial groove, less gibbous, and more globose. The apex is eroded in 

 all the specimens so that the exact number of whorls could not be 

 determined. The immature shells are about the size of S. coosaensis 

 and somewhat resemble that species, but differ in the thicker shell, 

 color, smaller and more regularly rounded aperture, which is scarcely 

 angled at the base, the upper extremity of the lip is also less curved 

 in at its insertion. 



Somatoyyrns georyianus n. sp. PI. v, fig. 13. 



Shell globose, turbinate, perforate, thick, .solid, light greenish- 

 yellow, smooth, except for fine growth lines. Spire short, obtuse. 

 Whorls about four, those of the spire convex with a well-impressed 

 suture, body-whorl large, very convex and inflated above. Aperture 

 large, obtusely-angled above and broadly-rounded below. Columella 

 concave with a very heavy, narrow callus, \vhich extends to the 

 upper insertion of the lip and is adnate to the body whorl only at its 

 upper end, and below the narrow umbilicus is separated from the 

 body whorl by a deep axial groove. Lip simple, but thickened 

 within, its insertion on the parietal wall is below the periphery. Alt. 

 (apex eroded) 5, diam. 4^ mm. 



Chattanooga river, Chattanooga Co., Ga. (type locality), also 

 Tennessee river, Cahawba river and Alabama river, Ala. (Lewis 

 Coll.). 



A couple of indifferent specimens have been in my possession for 

 several years, which were found among some Pleuroceridss collected 

 by R. E. Call. A larger suite in Mr. Hinkley's collection from the 

 same source, and three lots from the Lewis collection have served to 

 confirm the distinctness of the form. This species resembles S. sar- 

 genti (pi. v, fig. 14) in the inflation of the upper part of the body 

 whorl, but differs in lacking the shoulder characteristic of that species 

 and in the peculiar formation of the columella, which is unlike that 

 of any other species except S. pumihis Con. and S. trotht's Doh. It 

 also resembles S. crassns, hut is larger, the bodv whorl more elong- 



