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Show 1881.] THE SURVEY OF H.M.S. 'ALERT.' 105 SERTULARIA FUSIFORMIS, Hutton ? (non Hincks). Sertularia fusiformis, Hutton, Trans. N.Z. Inst. v. p. 257; Coughtrey, Trans. N.Z. Inst. vii. p. 285, pi. xx. figs. 21-23. This species appears to be represented by four specimens. The growth is very strong, and the calicles large ("425 millim. in diameter at their middle); but they should be described as quadridentate, though the interior and exterior teeth are very short. The crest, described by Coughtrey on the upperside of the gonangium, is here, at any rate, a tube which opens in the side of the gonangium. This is certainly not the species assigned to Hutton's species by Allman (Journ. Linn. Soc. xii. p. 263) under the name of S. episcopus. Hab. Trinidad Channel, S.W. Chili, 0-30 fathoms, on coral &c. HYDROCORALLIN^E. LABIOPORA ANTARCTICA, Gray. Porella antarctica, Gray, Ann. & Mag. Nat. Hist. ser. 4, ix. p. 482; P. Z. S. 1872, p. 746, pi. lxiv. fig. 4. Labiopora1 antarctica, Moseley, Phil. Trans. 1878, pt. ii. p. 476, pi. xxxv. fig. 5. A spirit specimen, the first obtained. It differs from the type specimen somewhat in habit. Instead of originating by a very broad stout stem, giving off stout branches which branch into rapidly tapering pointed twigs, the frond commences to branch almost at its base, the branches being cylindrical and only about half the diameter of those of the type specimen, which is of about the same size; hence their terminal divisions taper much less. The lips of the " nariform projections " are, as a rule, thicker than in the other case ; and hence their contained pores are scarcely visible to the naked eye. The specimen, which was obtained on the 29th of March, is well provided with ampullae (absent in the type specimen), about one millim. in diameter, projecting as low domes between the nariform projections over the greater part of the branches, some having already burst. The stock would therefore appear to be female • but examination of decalcified fragments failed to detect generative organs with certainty. The ccenosarcal canals are from "035 to "07 millim. in diameter; the meshes between them vary from the former diameter to about "14 millim. Hab. Trinidad Channel, S.W. Chili, 30 fathoms (coated with Cellepora, Sertularians, & c ) . (The type specimen was from a bank to the east of Tierra del Fuego.) 1 Characters of the Genus Labiopora.-With Mr. Moseley's concurrence, I propose that the distinctive characters of the dactylopores of his genus should be restated as follows :-" Dactylopores devoid of styles ; two kinds present, the one opening on the general surface of the ccenosteum, the other within special areas bounded hy nariform lips." This change is necessitated by the discovery of the following new species. The term "lew" should be omitted from the description of the branches, and also the statement that the nariform projections are inclined towards the tips of the branches and have their rounded margins on this side. |