Shell aciciilar, nuclear whorls light brown, the others white, excepting the narrow band that connects the tubercles into a spiral series which are brown. Nuclear whorls five, the first smooth, the rest marked by two, quite closely placed spiral threads, the posterior one of which falls on about the middle of the exposed portion of the turns. In addition to the spiral threads the whorls are marked by slender axial riblets, of which there are about twenty-four upon the second and twenty-eight upon the fifth turn. Post-nuclear whorls separatetl by deep sutures and ornamented from the very beginning by three tubercular spiral keels, of which the median is the most strongly and the anterior the least developed. All the tubercles slope very abruptly posteriorly, which lends them a somewhat truncated appear- ance at this end, and more gradually anteriorly. They are connected axially by slender riblets, of which there are about fourteen on the first, sixteen upon the fifth, and eighteen upon the penultimate postnuclear whorl. Periphery of the last whorl marked by a slender tuberculate keel in the immature shell. Base sloping concavely from the keel to the columella; without spiral keels, crossed by the feeble continuations of the axial riblets which gradually evanesce as they approach the columella. Aperture subc|uadrate, irregular, strongly channeled anteriorly, outer and basal lip conforming with the external sculpture and slope, columella short, stout and slightly twisted.