Report on the zoological collections made in the Indo-Pacific Ocean ...

;618 COLLECTIONS FROM THE WESTERN INDIAN OCEAN.approximately cylindrical stems, 50 by 13 and 80 by 20 millim. respectivelyin greatest height and thickness, arising close togetherfrom a common rocky base. The lower end of the larger one isalmost smooth for a distance of about 8 millim. ; the remainder, aswell as the whole of the smaller stem, is beset with small, slender,wedge-shaped or pyramidal eminences, sometimes forked, 2-3 millim.high, about 2 millim. in diameter at their bases and 2-4 millim.apart at their summits ; the general surface between these processesis honeycombed with circular openings, "5 to 1-OmiUim. in diameterand '25 to 1*0 millim, apart. Consistence rigid, slightly compressible,tough. Colour very pale buff.Skeleton typically Axinella-like ; fibre 3 or 4 spicules broad;spicules united by dense, very pale yellow horny fibre ; axialmeshes close, '18 to -3 millim. across, the reticulation extending toexterior of sponge. Sarcode pale yellow, subtransparent. Spiculessmooth acuate, curved more or less boldly at from one third toone half of the distance from the base ; base well rounded ; spiculestapering to sharp points from about their middle ; size "35 by '019millim. In Lamarck's specimen the surface-tufts are smaller andonly 1-2 millim. apart, the sponge is more fiattened than here, andthe spicules are slightly smaller, viz. -31 by '018 millim.Hab. Darros Island, Amirante group, 22 fms.Distribution. King Island, Australia (LamarcJc).41. Axinella proliferans. (Plate LIII. figs. E, E'Plate LIV. fig.Erect, with short flattened stem, expanding into fiabellate fronds,which towards their ends proliferate into secondary fiabellate frondletswhich assume a course parallel to that of the main frond ; as thelatter is frequently plicate at its free margin, the aspect on lookingdown at a large specimen from above is that of a number of irregularfunnel-shaped cells, bounded by lamellar walls, roughened by verynumerous slashed ascending ridges. Surface of frond beset, at intervalsof about 4 millim., with sharp ridges 3-4 millim. high (5or 6 millim. near upper margin) ; the ridges notched at intervals ofabout 3 millim. by ascending teeth, 1-3 millim. high, or altogetherreplaced by longitudinal series of flattened, notched teeth.Vents in spirit- specimen formed by circular openings, 1-2 millim.wide, leading obliquely downwards, scattered between the bases ofthe laeiniate surface-tufts and ridges of the sponges, chiefly nearthe free margins of the latter. Texture in dry state tough, subelastic; of stem and midribs firm, woody, of margins of fronds andridges fiexible ; in spirit, all parts relatively more pliable. Colourin dry state pale yellow-brown to rufous-brown, in spirit pale salmoncolour.Cortical skeleton appearing on margins of surface-tufts and in someplaces on face of frond as tufts composed of a few of spicule no. 1,connected by their bases ; in main stem consisting of confused linearc.)