Descriptions of New Fluviatile Shells. 107 



Shell conical, thin, brownish-olive ; spire obtusely elevated ; 

 whorls 7-8, smooth ; the upper ones are surrounded by a sharp 

 elevated keel just above the suture ; the body whorl is angu- 

 lated in the middle by two keels, of which the upper is the 

 more prominent ; sutures deeply impressed ; aperture ovate, 

 ending in an acute angle below, whitish within ; columella 

 rounded, produced into a narrow but slight sinus. 



Length 0.50 inch (13 millim.). Diam. 0.28 inch (7 millim.). 



Length of aperture 0.26 inch (7 millim.). 



Breadth of do. 0.1-1 inch (3J millim.). 



Habitat. — Battle creek, Tennessee. 

 My cab. Cab. Lye. Nat. Hist., K Y. 



Obs. — Bears some resemblance to II. acutd-carinata Lea, but 

 differs from it in many particulars. It is of a much lighter 

 color, has the carina on every whorl, the body whorl not ex- 

 cepted, its columella is not remarkably indented as in that 

 species, and it is altogether a thinner and broader shell. The 

 aperture is generally uncolored, but some specimens present a 

 faint tin°;e of violet there. 



27. jflelaiiia eximia. 



Plate III. Fig. 1. 



Testa conico-ovata, lirata, corneo-virente ; spira pariim elevata ; anfr. 

 8-9 ; superioribus carina acuta angulatis et fascia nigra cinctis, ultimo 

 liris 4 et fasciis duabus cincto ; suturis inconspicuis ; apertura elongato- 

 ovata, iutus cornea, bifasciata; labro valde sinuoso; columella recta, in 

 sinum profundum producta. 



Shell deeply sulcate and carinate, ovate ; of a beautiful light 

 apple-green color, ornamented with two dark-green bands, and 

 an elevated, prominent cariua of a light color revolving be- 



