Shell representing in form an isoceles triangle, convex, usually solid and thick, opaque, somewhat but not very glossy […] Numerous slight and irregular concentric striae, which often become laminar and almost rib-like in front and at the sides, and always at the dorsal margin ; lines of growth strongly marked. […] Habitat: in gravelly sand, at low tides and at the depth usually of only a few fathoms. – J. G. Jeffreys: British conchology vol. II, London 1863, via BHL.