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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.

Obtortio pyrrhacme, Melvill & Standen. — Fig. 6

Obtortio pyrrhacme, Melvill & Standen.
Fig. 6.

Melvill & Standen, Journ. Conch., viii., 1896, p. 310, pl. xi., fig. 70.

These authors describe from Lifu, Loyalty Islands: "A pure white ochre tipped shell, whorls eight or nine, much swollen, longitudinally ribbed, spirally closely sulcate, aperture round, lip simple, a little effuse." This account is illustrated by a figure too small to give details of sculpture, aperture or apex. To identify a species from such data is a little hazardous, but the brown point to the white shell is a peculiar feature which leads me to see in "Rissoa pyrrhacme" a common New Caledonian shell, long known to the local collectors under the, doubtless erroneous, name of "Fenella pupoides, Adams."* I have collected this at Panie, New Caledonia, a day's sail from Lifu, whence Melvill and Standen derived Rissoa pyrrhacme.

Fig. 6.

Fig. 6.

Among shell sand on the lagoon beach of Funafuti I gathered a dozen specimens specifically inseparable from the Panie shells which I thus identified. They are smaller than Melvill and Standen's specimens, being barely four millimetres in length, whereas theirs are six, the tips, unlike my Panie examples, are faintly and barely touched with colour, as if singed by fire. In contour they exhibit much variety; two examples are drawn to the same scale to illustrate diversity of proportion, perhaps a sexual feature. The apex, which I hold to exhibit characters of generic importance, consists first of two very minute whorls which are almost buried in the succeeding whorl. These are very difficult to observe, being seen in two instances only in the series examined. A globose whorl, longitudinally ribbed, sometimes only obliquely wrinkled, commences the real spire. This, the subsequent whorl and the tip, together form an acicular point to the shell when viewed through a handlens. The second, third, and fourth whorls are tabulate, lending a pagoda aspect to the

* Cf. Schmeltz—Cat. Godeffroy Museum, v., 1874, p. 104.

page 414upper spire. These are the whorls stained chestnut, so dark as to be almost black, in the New Caledonian specimens. The larger whorls are closely corded by spiral lyræ, having smaller lyræ in their interstices. Weak, longitudinal ribs undulate the central whorls and appear on the last whorl, but vanish there before reaching the periphery. The columella lip is broad and reflected, obliquely ridged within and sharply bent above. The aperture is perpendicular, ovate and grooved within.

Rissoa joviana of Melvill and Standen* appears to me to be an absolute synonym of Alaba fulva, Watson, These and Alaba striata, Watson should enter the same genus as pyrrhacme. Indeed I am not satisfied that all four names do not apply to aspects of one polymorphic species.

* Op. cit., p. 309, pl. xi., fig. 69.

Chall. Report, xv., 1886, p. 571, pl. xlii., figs. 5 a. b.

Op. cit., 569, pl. xlii., figs. 6 a. b.