Zoological Illustrations Series II/Plate 122



This highly elegant and delicate species was first described by us in the Catalogue of the Bligh Collection, at the sale of which a specimen produced five pounds. Latterly, however, the species has become more frequent: the figures are taken from a fine individual in our Museum, procured from China. The pure white of the surface is relieved by a slight iredescent or pearly gloss, similar to that on the scales of many fish: but which is probably concealed, in a state of nature, by a thick and soft epidermis, similar to that of Triton corrugatum, Lam.

The structure of this sub-genus is further remarkable for the prolongation of the basal end of the principal varex on the body whorl, which, in nearly all the species, is so prominent, as to give the shell an appearance of having two channels. It is remarkable that this horn-like process occurs in that part of the shell which is immediately above the head of the animal: so that even in this genus of Mollusca we see a manifestation of that principle of the natural system, by which one of the aberrant types of nearly all animals have crests, horns, or similar protuberances on or near the head.