Art. XLIX.—Descriptions of some new Tertiary Shells from Wanganui.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 15, 1882, Page 410

Art. XLIX.—Descriptions of some new Tertiary Shells from Wanganui. By Professor F. W. Hutton. [Read before the Philosophical Institute of Canterbury, 7th September, 1882.] A Short time ago a collection of over a hundred species of Mollusca from the Wanganui bed was submitted to me for determination by Mr. S. H. Drew, of Wanganui, and in it I found the following forms which appear to be undescribed:— Trophon expansus, sp. nov. Shell ovate; spire moderate, acute: whorls five or six, spirally grooved, the grooves narrower than the ribs, about 26 grooves on the body-whorl, crossed by undulating laminæ of growth worn smooth. Aperture ovate, wide, slightly angled behind; outer lip expanded; columella rounded, with a small posterior canal: anterior canal very short and recurved. Length, .77 inch; breadth, .4 inch. Length of spire, .3; of aperture, .35; of canal, .12 inch. This is one of the purpuroid Trophons, but with a rounded columella; it is so like the figure of Purpura patens, H. and J., that I should have considered it the same, but that the authors state that P. patens has the columella very flat. Cominella drewi, sp. nov. Shell ovate, spire short: whorls six, spirally lirate, about 22 liræ on the body-whorl; the spire-whorls finely longitudinally plicate. Aperture ovate, the posterior canal well marked: columella obliquely truncated; anterior canal well defined. Length, .78 inch; breadth, .45 inch. This species is distinguished from all our other species of Cominella, except C. ordinalis, Hutton, by being spirally lirate, and from this species it is separated by its well-marked anterior canals, which makes it intermediate between Cominella and Euthria.

Odostomia sherriffi, sp. nov. Shell subulate, tapering: whorls fifteen, smooth, flattened and polished, the suture deep. Aperture ovate; peritreme not continuous; columella with one strong plait. Length, .55 inch; breadth, .17 inch. Named after Mr. G. Sherriff, of Wanganui. Trochita inflata, sp. nov. Shell subglobose; whorls two and a half rounded; the last inflated, with four or five distant, narrow, spiral ribs crossed obliquely by lines of growth: apex lateral. Aperture ovate, the lamina concave. Height .4 inch. Length of aperture .88; breadth .72. This species has externally the appearance of a Natica, but the surface is not polished. Anthora conica, sp. nov. Shell conical, high; whorls seven, slightly convex, with fine spiral moniliform ribs, about eight on the penultimate whorl; suture deep; base of the last whorl spirally striated with moniliform striæ, the angle rounded. Axial cavity deep, smooth, conical; columella with a slight posterior fold. Height .84 inch; breadth .84 inch. This species has the smooth axial cavity of A. tiarata, but it is larger, higher, the granulations finer, and the basal angle much more rounded. Note.—In addition to these new species there was in the collection a specimen of what I take to be Siphonaria fuscozonata, Angas (P.Z.S., 1865, p. 56), which appears to be the same as Fusus minutisquamosus, Reeve.