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Volume 38, 1905
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Leda bellula, A. Adams.

Leda bellula, A. Admas, P.Z.S., 1856, p. 49. Id., Hanley, Thes. Conch., iii, 1860 p. 122, pl. 228, f. 74.

A species which occurred abundantly answers fairly to the above quotations. But the lithograph, fig. 25 of pl. v, “Leda,” in Conch. Icon., vol. xviii, is so bad a copy of the figure in the Thesaurus that it looks like a different species.

A. Adams, whose name is the danger signal for untrustworthy work, reports the species as taken by F. Strange in Australia. But, on the one hand, no Australian shell like this is known to me, and, on the other, Strange collected extensively in New Zealand. Indeed, he was the first, and for half a century the last. to dredge off the New Zealand coast, and discovered many of the species enumerated in this report. I am therefore disposed to think that “Australia” has been substituted here for “New Zealand.” The species before me is that known to all conchologists in New Zealand as Leda concinna. The figures of Leda concinna more nearly express the proportions of Poroleda lanceolata than any other member of the New Zealand fauna, and are incompatible with the traditional determination.

Leda fastidiosa, A. Adams. Plate I, figs. 1, 2.

Leda fastidiosa, A. Adams, P.Z.S., 1856, p. 49. Id., Hanley, Thes. Conch., in, 1860, p. 125, pl. 228, f. 82, 83.

A considerable number were dredged. The concentric sulci vary from the least trace to considerable development, but are never so coarse and regular as in the last species. Besides being smoother than L. bellula it is more inflated, and is further distinguished by a microscopic punctate pattern. The length of the figured specimen is 7 mm. and the height 4 mm.

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This species was first described from New Zealand, probably from Strange's collection, but has never been recognised again, either there or elsewhere, and was eliminated from the New Zealand list by Hutton (P.L.S.N.S.W., ix, 1884, p. 527).

Poroleda lanceolata, Hutton. Plate II, fig. 7.

Scaphula (?) lanceolata, Hutton, Trans. N.Z. Inst., xviii, 1885, p. 332. Poroleda lanceolata, Hutton, Macleay Memorial Vol., 1893, p. 86 (not Poroleda lanceolata, Tate, Proc. Roy. Soc. N.S.W., xxvii, 1894, p. 186 = Poroleda tatei, Hedley, “Victorian Naturalist,” xxi, Dec. 1904, p. 112)

The name of this species is involved in some confusion. Professor Tate, in March, 1894, introduced a new species, type of a new genus, under the title of Poroleda lanceolata But in the previous September-Captain Hutton had redescribed his fossil under the same name. Since Poroleda lanceolata was in current use for both the New Zealand and the Australian shell, I have proposed to distinguish that which Tate figured and described from the Gellibrand River beds of Victoria as Poroleda tatei.

In colour, texture, and all particulars save those of the hinge-teeth this species closely resembles Leda ensicula, Angas, L. lefroyi, Beddome, and L. huttoni, Tate. These five species might suitably be included in Poroleda.

Hitherto P. lanceolata has been known only as a Tertiary fossil. Mr. A. Hamilton has shown me a broken valve from off Anchor Island, Dusky Sound. In our 110 fathoms dredging it occurred plentifully. The size of the specimen drawn is-height, 3·85 mm.; length, 13·8 mm.; breadth of single valve, 0·9 mm.