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

SPOXGIIDA. 4451. Slender acuate (slightlyinflated basally)2. Stout long acuate (veryTorres Straits specimen.-25 to -31 by -0042 to -005 millim.scarce) About -19 by -0095.3. Spined echinating acuate-085 by -0044.4. Equianchorate -014 to -016 long.Hah. Prince of Wales Channel, Thursday Island, &c., TorresStraits, 4-10 fms. ; bottom sand &c. ; common.From stiidy of the present series of specimens, with the lightaiforded by W. Marshall's important paper, " Untersuchungen iiberD3sideiden und Phoriospongien" (Zeitsch.wiss. Zoo], xxxv. p. 122),I am now convinced that Bowerbank was right in describing thearenaceous material which is so plentifully present in this spongeas the normal substratum of the skeleton-lines, and that it does not,as I formerly considered (P.Z.S. 1881, p. 122), consist of the tubesof an arenaceous Foraminifer. That being so, the character assumesa fresh importance when it is seen not to stand alone among theSiliceous Sponges. PAorzospom/m, Marshall {l.c.\ is described ashaving a spiculation consisting of acei'ate and (or) spinulate andbihamate spicules in combination with a large quantity of sand, thelatter, however, not aggregated into definite fibres. With regard toClatliria tuberosa, though it diff'ers from other Clathrice in thisremarkable point, its spiculation is distinctly that of the genus towhich I propose to refer it.76. Clathria coppingeri.(Plate XL. figs. F, F' ; Plate XLII. figs, i, i' .)Erect, palmate, clathrous, groAving in only one plane. A fewmain branches are given off from the common base or rudimentarystem, each dividing furcately once or twice at acute angles ; theterminal branches are traceable to within about two thirds of thedistance from the base to the periphery of the sponge. All thebranches intimately united by a close reticulation, consisting of barsof sponge-substance, suboblong in transverse section, the longestdiameter being the antero-postcrior one, the anterior and posteriorsurface of the bars either flat or coming to an angle in front orbehind or on both aspects ; the surface of the sponge thus presentsa series of subquadrangular, polygonal, or suboval cells, havinga maximum diameter of 3 to 10 millim. Main branches suboblongin transverse section, the antero-posterior diameter being longerthan the lateral one : slightly marked by longitudinal furrows, theanterior and posterior faces flat or angular ; the branches (especiallythe larger ones) project above the level of the intermediatereticulation, owing to their superior antero-posterior thickness, whichattains a maximum of 20 millim., the lateral diameter a maximumof 10 millim. Surface of intermediate reticulation, sides of main