The shell is slender, black with a few inconspicuous, pale spots in the peripheral region. Nucleus lost; six whorls remaining are convex in the middle, a little compressed below the suture. Axial sculpture of small ribs on the last whorl, where they scarcely reach the suture and diminish rapidly below the periphery, and fine but sharp, close incremental striae. Spiral cords six on the penult, 21 on the last whorl, the presutural cord a little prominent, several below it smaller than those of the peripheral region. Aperture about as in N. poecila-, the lip preceded by a slight swelling, and with a shallow anal sinus, four weak internal denticles. Columellar lip with thick outer edge and no denticles within. Length 4.4 mm., diam. 1.9 mm. A smaller, more slender form than N. poecila, the ribs much smaller.