Page:Transactions NZ Institute Volume 15.djvu/514

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Description.—Rhombic, in radiating groups, which separate in thin flexible lamina?. Hardness 2 to 2.5; colour, whitish green to dark green, weathering to a bronze hue and pearly lustre. B.B. infusible, but becomes white; odour, bitter argillaceous when breathed upon. Allied to picrosmine and antigorite. It is from the Dun Mountain, where it occurs with the serpentine rocks. It was collected by the late Mr. E. H. Davis.

Art. XLIX.—-Descriptions of some new Tertiary Shells from Wanpanui. By Professor F. W. Hutton. [Read before the Philosophical Institute of Canterbury, 1th September, 1882.] A short time ago a collection of over a hundred species of Mollusca from the Wangauui 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 lamina? 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, •85; of canal, *12 inch.

This is one of the purpnroid 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 fiat.

Cominella drewi, sp. nov.

Shell ovate, spire short: whorls six, spirally lirate, about 22 lira? 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.