| OCR Text |
Show 1881.] THE S U R V E Y O F H.M.S. 'ALERT.' 45 With regard to the fauna of the southern coasts of South America, we have already, in the British Museum Catalogue of 1852-75, had considerable insight into it, thanks chiefly to the collections brought home by Mr. Darwin ; and a statement of its richness in its more equatorial parts has been placed on record by the late Dr. Willimoes-Suhm in a preliminary Report: on the observations made on the ' Challenger,' referring to dredgings made off the Brazils. This latter statement is fully borne out by the contents of the present valuable collection. A striking instance in point is that of a haul taken at Victoria Bank, off Brazil, of which the Polyzoan contents could be contained in a pill box, but which included seven species, among them several of the relatively bulky species of the genus Celle-pora, and a representative of a new genus. A few shreds of a thin Fucus from Elizabeth Island in the Straits (6 fathoms depth) produced no less than 99 colonies or portions of colonies, representing nine species. In the new species assigned to Chaunosia, Busk, we have the interesting case of a fellow being found to a species from across the Atlantic at the opposite mainland, the Cape of Good Hope. Species known as fossils have appeared in the shape of Cellepora tubigera, Busk (already known from European seas), and the beautiful Discoporella grignonensis, Busk, not previously known in the recent state. One species (a new one) belongs to the Endoprocta {Pedicellina), none to the Ctenostomata ; six to the Cyclostomata (of which three are Tubuliporce, one a Discoporella, one a Diastopora, one an Ld-monea). Of the Chilostomata but one species of the Articulata (Busk, Cat. Mus. Brit.) occurs; the rest, numbering 25 species, belong exclusively to the generally more highly calcified group Lnarticulata (Busk, I. c). This is rather striking, considering the abundance in which the Catenicellidcs and kindred forms occur off Australia ; but it serves to draw attention to the fact that the fades of the fauna is Atlantic rather than Australian or Novo-Zelandian. CHILOSTOMATA. CANDA ? sp. A few badly preserved fragments from Victoria Bank2, off S.E. Brazil, 39 fms. CHAUNOSIA FRAGILIS, sp. n. (Plate VI. fig. 1.) Chaunosia, Busk, Quart. Journ. Micr. Sci. (n. s.) vii. p. 241. Zoarium horny, with the exception of the calcareous distal portion of the spines. Zocecia erect, distinct, crowded, each standing at the junction of four uniting branches of the tubular stolon, which is their only point of attachment; somewhat convex behind and at the sides, straight in front, where they appear to lie open by a space of about three fourths of the breadth of the front of the cell; tapering 1 Proc. Boy. Soc. xxiv. p. 572. 2 Not marked in the usual maps; its position is lat. 20° 42' S., long 37°27'W. # |
