« With raised concentric striae, which are decussated behind by a few elevated radiating lines. […] When fresh taken it is usually covered with a dull ashy olive-coloured epidermis, beneath which the surface, which possesses but little if any lustre, is either rayed with madder-lake and white, (the preponderance of colour varying with the individual) or marbled in a linear fashion, with the former, on a whitish or pale-coloured ground. It is closely striated for its entire length with raised concentric lines, which not unfrequently at their posterior termination dentate the hinder dorsal edge. These striae are decussated beyond the umbonal ridge, which is indicated by a sharp elevated line, by a few fine radiating ones, which in the adult, however, do not quite proceed to the extremity of the shell. » Etc.