252 LAND AND FRESH-WATER SHELLS OF N. A. [PART IV. 



Melania suhsolida. — ^'heW smooth, subfusiform, somewhat solid, 

 horn-colored ; spire acute ; sutures impressed ; whorls somewhat con- 

 Fig. 490, vex; aperture somewhat elongated, within purple. 

 Habitat. — Tennessee; Dr. Troost. 

 Diameter, -32 ; length, -82 of an inch. 

 Observations. — This species has a strong resemblance to 

 M. simplex, Say. It is, however, more elevated in the spire. 

 It is purplish within, but white towards the margin of the 

 lip. — Lea. 



Melania densa. — Shell solid, elongately ovate, acuminate, light 

 olivaceous ; spire produced ; whorls G-7, ventricose, angulated below, 

 the upper ones small, the last subcylindrical, equalling two- Fig. 490a. 

 thirds the length of the shell; aperture narrowly ovate, 

 scarcely effused, rounded in front; columella quite cal- 

 lous; within yellowish. 

 Habitat. — Maury's Creek, Tennessee. 

 Longitude, J ; latitude, f poll. 

 Observations. — Somewhat like M. basalis, Lea. The 

 shelving of the whorls towards the suture and the acumination of the 

 spire are among its most striking characters. — Anthony. 



Goniobasis Vanuxemii. — Shell smooth, fusiform, rather thick, horn- 

 color; spire obtusely couical; sutures impressed; whorls seven, 

 Fig. 491. slightly convex; aperture large, subrhomboidal, white or pur- 

 ple within ; outer lip acute, slightly sinuous ; columella bent 

 Mm in, thickened above and below. 



Operculum ovate, very thin, light brown, with the polar 

 point near to the base on the left. 

 Habitat. — North Fork of the Holston River, Virginia; Prof. L. 

 Vanuxem. 

 Diameter, -27 ; length, -54 of an inch. 



Observations. — Many years before the decease of my lamented 

 friend. Prof. Vanuxem, he gave me a number of mollusca collected 

 during his journeys in South Carolina and AVest:-i-n Virginia. Among 

 them was quite a number of this little species which I now dedicate 

 to him. It is nearly allied to Melania (Goniobasis) Niagarensis 

 (nobis), but is a small species with a shorter spire, and is straighten 

 at the base of the columella. The aperture is rather more than one- 

 third the length of the shell. — Lea. 



