GASTEROPODA. 131 



Formation and locality. In limestone above the hydraulic beds, of the age of 

 the Hamilton group, at the Falls of the Ohio. 



This and the L. keviusculum have been communicated by Dr. James Knapp, of 

 Louisville, Ky. 



LOXONEMA L.EVIUSCULUM, n. Sp. 

 PLATE XXVIII, FIGS. 10, 11. 



Shell elongate, subulate. Volutions about twelve in the entire shell, rounded 

 and somewhat rapidly expanding to the last one, which is moderately 

 ventricose. Suture close and simple. Aperture ovate, the columellar lip 

 much extended below. 



Surface nearly smooth or marked by faint obsolescent striae, which are mod- 

 erately curved over the convexity of the volution, and become fasciculate 

 on the lower side of the last one as they approach the columellar lip. 



This species has the general aspect of L. Hamiltonia, but it is less rapidly 

 tapering towards the apex, the volutions somewhat less convex, and the last 

 one not so ventricose as in well-preserved specimens of that species. Usually 

 the specimens have the appearance of being worn and macerated, and the 

 general absence of striae upon the surface may be due in part to this cause ; 

 but they are associated upon the same surface with L. hydraulicum, which, in 

 similar conditions, has retained its surface-striae in good preservation. This 

 species is readily distinguished from L. hydraulicum by the less rounded volutions 

 and slighter constriction at the suture. It is more rapidly tapering than L. rec- 

 listriatum, with which it is associated, and has no constriction of the upper part 

 of the volution as in that species. 



A specimen preserving nine volutions, including the last one, measures about 

 one inch and a quarter. 



Formation and locality. In limestone above the hydraulic beds, of the age of 

 the Hamilton group, at the Falls of the Ohio. 



