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The Atoll of Funafuti, Ellice group : its zoology, botany, ethnology and general structure based on collections made by Charles Hedley of the Australian Museum, Sydney, N.S.W.

Triforis Ruber, Hinds. — (Fig. 29)

Triforis Ruber, Hinds.
(Fig. 29).

Hinds, Ann. Mag. Nat. Hist., xi., 1843, p. 18.

The species before me is the most abundant, conspicuous and widespread of the genus in the tropical Pacific. If I have page 442correctly identified it, the shell was first taken by Belcher during the voyage of the "Sulphur." He noticed it at Port Carteret, New Ireland, as "numerous among fine gravel at low water." There are two colour varieties of this shell—-one pale, the other dark. Conchological tradition appears universally, but I think erroneously, to regard the dark form as T. ruber and the pale as T. violaceus of Quoy and Gaimard. For the purpose of specific determination the descriptions of all older writers, and most modern ones, of species of Triforis are worthless. The identity of T. violaceus must be decided by the illustrations of that species in the "Atlas of the Voyage of the Astrolabe." This shows a slender and produced anterior canal, and an anal notch projecting as a complete tube, remote from the aperture. Specimens answering to these details, which I collected in Milne Bay, British New
Fig. 29.

Fig. 29.

Guinea, are before me. Though Quoy and Gaimard may themselves have confounded distinct species, and though Kiener's figure from "Astrolabe" material appears to disagree with the former illustration, yet the only safe point of departure in unravelling the nomenclature of this group must be Figs. 22 and 23 of PL. Iv. of the Atlas aforesaid. In the particulars of the anal and anterior orifices, the shell before me, presumed to be T. ruber, differs altogether, as the accompanying drawings show.

In the unsatisfactory state of literature, the following remarks may not be deemed superfluous.

This species varies in size, stoutness, and colour; from the adult an immature shell so differs in outline, that a collector does not at first recognise it as the same kind, for it much resembles Triforis gemmulatus, Adams and Reeve.* As a whole the contour of the adult shell resembles that of a carrot, the upper whorls page 443tapering to a slender point, the lower swollen to bulbous. Colour, which alters in drying, reddish purple to lilac, the apex and the lower row of gemmules usually cream. Whorls about eighteen. Genimules subcircular, polished bosses, shelved above, separated by about half their own diameter, in two rows of about twenty-two in a whorl, alternating vertically; the interspaces between the gemmules are spirally wrinkled. On the antipenultimate whorl a spiral thread arises between the two rows of gemmules, but following the sinuations of the upper, this gradually increases, becomes segmented, and on the last whorl forms an additional row of gemmules. Just behind the aperture extra rows are also intercalated. The protoconch is acicular, four or five whorled, the whorls bicarinate, crossed obliquely by numerous fine bars, which bead the carinæ. The aperture is perpendicular, almost square, lip reflected, the right margin crossing the canal in a spur, the canal being closed by its anterior wall folded over, but not touching the pillar. Anal notch deep, a subcircular, subfcubular, orifice in the place of the last sutural gemmule; onwards from the last actual gemmule the lip is free from the body whorl. Length 7½ mm.

Common in shallow water in the lagoon of Funafuti. As the rare T. violaceus has been generally confounded with the common T. ruber, whose aperture is quite different, most literary records are untrustworthy, and I forbear to quote them. I have myself collected the species at Port Moresby and Milne Bay, British New Guinea, and at Oubatche and Noumea, New Caledonia. Specimens of T. ducosensis, Jousseaume, received from Noumea, from Mr. R. C. Rossiter, belong to the pale form of T. ruber.

* Adams & Reeve—Zool. Samarang, 1850, Mollusca, pl. xi., fig. 34