Shell minute, broadly ovate, yellowish white. Nuclear whorls one and one-half, well rounded, smooth. Post-nuclear whorls somewhat inflated, slopingly shouldered at the summit, marked by very slender, almost vertical, axial ribs, of which 18 occur upon the first, and 20 upon the penultimate turn. In addition to the axial sculpture, the whorls are marked between the sutures by two spiral cords equaling the ribs in strength. Of these, the first is a little posterior to the middle of the whorls, bounding the sloping shoulder, while the second is halfway between it and the suture. The intersections of the axial ribs and spiral cords form slender tubercles, while the spaces inclosed between them are well impressed, squarish pits. The spaces inclosed between the first spiral cord and the summit and the axial ribs are rhomboidal areas, having their long axes parallel to the axial sculpture, while the spaces inclosed between the second spiral cord and the axial ribs and the suture are squarish pits. Suture moderately constricted. Periphery of the last whorl marked by a spiral sulcus, which is crossed by the continuations of the axial ribs. Base narrowly umbilicated—the umbilical chink being bounded by a tumid area—moderately long, well rounded, slightly produced anteriorly, marked on the posterior half by two spiral cords equaling those between the sutures. Aperture almost circular; outer lip very thick all around, reenforced by a strong varix; inner lip very stout, partly reflected over, and appressed to the base; parietal wall covered with a very thick callus which renders the peritreme complete.
The type (Cat. No. 23749a, U.S.N.M.) comes from Santa Barbara Island, California. It has three post-nuclear whorls and measures: Length 1.5 mm., diameter 1 mm.

Shell elongate-ovate, thin, semitranslucent. Nuclear whorls one and a half, well rounded, smooth. Postnuclear turns marked by two strong, spiral keels, the first of which is situated about two-thirds of the distance between the summit and the suture anterior to the summit, while the second is about one-fifth of the distance above the suture, leaving the space between the two, equal to about two-fifths of the distance. The space between the summit and the first keel, forms a strongly sloping shoulder, while the space between the two keels is almost flat. Periphery of the last whorl marked by a strong, spiral cord. Base well rounded, marked by three subequal and equally spaced, low, spiral cords. In addition to the spiral marking, the whorls are marked by numerous, very fine lines of growth. Aperture broadly ovate; posterior angle obtuse; outer lip thin, showing the external sculpture within; inner lip thin, slightly reflected; parietal wall covered with a thick callus which renders the peritreme complete.
The type, Cat. No. 250394, U.S.N.M., conies from Port Alfred (Coll. No. 1267). It has three postnuclear whorls, and measures: Length, 2.1 mm.; diameter, 1.3 mm.