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

;SPONGIIDA. 443diameter about -07 millim. ; one or two axial series of spiculesboth sets of fibres echinated sparsely with the echinating spicule.Dermal skeleton formed by undulating, very pale yellow hornyfibres containing two or three series of spicules, about '053 millim.broad, and of loose tracts of spicules. Sarcode pale amber-yellow,transparent.Spicules: — (1) Skeleton cylindrical, smooth, straight, taperingslightly from middle towards well-rounded ends ; size about -2 by•0042 millim. (2) Echinating acerate, smooth, straight, taperingdecidedly from middle towards the base, which is thus thinner thanthe middle of the shaft, but is well rounded, and tapering frommiddle to sharp point at apex ; size about 'IS by -0095. (3) Tricurvateacerate, smooth, curves slight, ends finely pointed ; sizeabout -042 by "0021 ; in sarcode.Hab. Port Molle, Queensland, 12 fms. ; bottom rock and coral.In general appearance this sponge resembles Clathria frondifera,but has the intervals between the trabecula) of the clathrous structuremore or less filled with membranous expansions. The spiculationis not quite so simple as that of the British species, but has, inaddition to their echinating acerate and tricurvate, a cylindricalskeleton form. I know of no other near allies. A small but wellpreserveddry specimen represents this species.74. Clathria aculeata.(Plate XL. fig. I ; Plate XLII. fig. k.)Erect, with single, slender stem, dividing into branches at somedistance from base ; branches given off in various planes and atacute angles, occasionally connected by bars of sponge-substance ;secondary branches occur, formed in the same manner as the primarybranches. Stem cylindrical, 4-5 millim. in diameter in presentspecimens ; surface even, with the exception of a few prominentbut blunt aculcations shortly below the commencement of thebranches ; branches well covered by long, more or less pointedaculeations, 2 to 5 millim. high. Texture of stem, both in spiritand in the dry state, woody, incompressible ; that of the brancheselastic, but more or less incompressible until near the apices, whichare firm but compressible. Colour, in spirit, dark amber-brown ; indry state pale brown, the branches having a whitish incrustedap])earance. Surface of branches, in spirit, minutely uneven, thatof stem glabrous.Main skeleton composed of very strong amber-yellow horny fibre,tortuous and anastomosing, not showing distinct separation intoprimary and secondary fibres, but forming oval meshes ; diameter offibre at base of branches varying from "Oo to -2 millim., the shortdiameter of the meshes formed by it at the same spot from -18 to•8 millim. : fibre cored by a tract of slender spinulate spicules, 3or 4 spicules broad, and echinated everywhere abundantly by thespined acerate spicule. Dermal skeleton similar to main skeleton,