Diagnosis. Small, 20-25 mm; valves uniformly white, tan or pale orange, central areas with fine riblets, radial areas rather smooth (sometimes with 1-3 sulci), with a few scattered or incomplete rows of granules; girdle scales very small, with 14-16 fine riblets. Habitat. Found on vertical rock walls, cobbles or shells, at 25-1400 m.
Distribution. Sitka, Baranof Island, Alaska to northern Baja California. Occurrence. Very rare to rare. Most often obtained in deep water trawls.
Comments. I have taken a single specimen at 25 m on a wall, near Vancouver, British Columbia. Previously reported from Georgia Strait in deep water (217 m), by Cowan (1964).