Shell elongately pyramidal, or wedge-shaped, white, glassy, and hyaline. Whorls fine, rather rounded, suture well marked, the body whorl sub-angular at the periphery. Aperture nearly round, the columella lip slightly reflexed; on a side view the outer lip slopes well back from the perpendicular. The columella is simple in the type and in some co-types, but in others a small tooth-like plait appears, which, however, I think is not a true plication, but is certainly a remarkable feature. Length 2, breadth 1.3 mill.
Locality—Type, with 20 others, from 100 fathoms, 7 miles east of Cape Pillar. This seems most nearly related in form to R. flammea, Frauenleld, but is longer, with another whorl, and of a thin hyaline texture.