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. * * * * * * [Illustration: ACHATINELLA. Pl. 3. _1. rosea. 2. pulcherrima._] ACHATINELLA rosea, _Rosey, reversed Achatinella_. ---- SUB-GENERIC CHARACTER. See pl. 99 and 108. ---- SPECIFIC (?) CHARACTER. _Shell reversed, ovate-oblong, sub-ventricose, pale rose colour, with obsolete white bands._ Ach. bulimoïdes (var. rosea) _Swains. in Brand's Journal Cap. 1828, p. 85._ ---- The figures on this plate complete the illustration of our monograph of this pretty and interesting group of shells. At present, we feel undecided whether this is a species, or a variety of _A. bulimoïdes_, from which it differs in being reversed, in having the marginal groove very distinct, instead of scarcely perceptible, and in colour. We possess only two specimens which came, with all the others, from the Pacific Islands. ---- ACHATINELLA pulcherrima. _Fig. 2._ _Shell ovate-oblong, sub-cylindrical, white or yellow, with broad bands of chesnut; margin of the lip, brown._ Ach. pulcherrima. _Sw. ut. sup. p. 86._ ---- This species is the most lengthened in form, and the most beautiful in colour of all those we have yet seen: some individuals, however, are more ventricose than others and the colours are no less variable. The ground colour is usually of a rich and deep chesnut, with from one to three bands of orange yellow, fulvous, or white; we have figured a further variety of a rich golden yellow with a chesnut line only at its suture: but in all these the marginal groove is very close and distinct. * * * * * * [Illustration: ANTHOMYZA _Tiresina_. 2 _heliconides_.] ANTHOMYZA Tiresia. _Three banded Burnet._ ---- Tribe, Sphingides. Family, Anthoceridæ. _Sw._ Genus ----? Sub-genus. ---- SUB-GENERIC CHARACTER.