Art. XXI.—Descriptions of Two New Gymnoblastic Hydroids.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 27, 1894, Page 208

Art. XXI.—Descriptions of Two New Gymnoblastic Hydroids. By H. Farquhar. [Read before the Wellington Philosophical Society, 20th February, 1895] Plate XIII. (in Part). Coryne tenella, n. sp. Plate XIII., fig. 5. Hydrocaulus simple or sparingly branched, slender, lax, pale horn-colour, attaining a height of about 15mm., arising from a creeping filiform stolon. The stems are smooth except at the base, where there are a few annulations, and the branches are sometimes slightly corrugated immediately above their origin. Hydranths elongate, cylindrical, sometimes slightly clavate, pellucid-white, with frequently a yellowish-brown tinge. Tentacles pellucid-white, with small spherical knobs, twenty-five to thirty in number, a verticil of four or five round the mouth, and another lower down; the rest scattered and frequently crowded on the lower part of the hydranth, sometimes with an indistinct tendency to a verticillate arrangement. Gonophores oval, sessile, in a cluster of three to five on the lower part of the hydranth among the tentacles. Hab. Wellington Harbour. On the roots and stems of Macrocystis pyrifera. Type specimens in the Canterbury Museum, Christchurch.

Tubiclava rubra, n. sp. Plate XIII., fig. 6. Hydrocaulus slender, lax, sparingly branched, attaining a height of about 12mm., arising from a creeping filiform stolon. Hydranths fusiform, very contractile, deep vermilion. Tentacles somewhat scattered, forming three irregular verticils, the lower ones rather smaller than the others, pellucid – white, contractile. Perisarc smooth or slightly annulated below, colourless and transparent, usually invested by minute plants and animals. The coenosarc in the stems and stolon is of a light-reddish colour. Gonophores sessile, red, developed on separate stems, three or four on the summit of a stem. Hab. Wellington Harbour. Abundant on the roots and stems of Macrocystis pyrifera. Type specimens in the Canterbury Museum, Christchurch. Very few New Zealand gymnoblastic hydroids have been described. I know of only three other species—viz., Tubularia attenoides, Coughtrey (Trans. N.Z. Inst., vol. viii., p. 302, 1875), from Dunedin; Eudendrium novce-zelandice, Marktanner-Turneretscher (Annal. d. k.-k. Naturhist. Hofmuseums, band v., p. 201, 1890), from Auckland; and a species of the freshwater genus Cordylophora found by Mr. A. Hamilton in the Esk River, near Napier (N.Z. Journal of Science, vol. i., p. 419, 1883), which Mr. Hamilton doubtfully identified as the European form C. lacustris, quoting Professor Allman's description of the genus. It is more likely to be identical with the Australian species, C. whiteleggii, v. Lendenfeld (Zool. Jahrbücher, bd. ii., p. 97, 1886). When rediscovered, however, it will probably prove to be distinct from both the European and Australian forms. The fact that so few species have been recorded does not by any means indicate that our hydroid fauna is poor and deficient in this group, but only that they have been neglected by New Zealand naturalists. Mr. H. B. Kirk informs me that he has found a species at Kau Bay, on the south side of the Wellington Harbour, perhaps the Coryne described above. I have myself collected specimens of a very beautiful Tubularia on the roots of Lessonia, at Ohiro Bay, near Wellington, which I believe is distinct from Dr. Coughtrey's species, and I have seen the polypidoms of several other species. No doubt a careful and systematic search would reveal many new and interesting forms.