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

SPONGIIDA. 379and non-rectangular arrangement with those of Euspongia,, and, asstated already, foreign bodies are the exception even in the surfacetufts; the diameter of the fibres is "4 to -7 millim. (Ehlcrs gives -5to '8), except in the delicate Ditela-netw ork of the surface and interstices,where it is •0085 to '022 millim. Ehlers says that thefibres contain " in der Axe vereinzelte sehr diinne spitz-spitzeNadcln (0-1 mm. lang, -006 mm. breit) welche nur in den kegelformigenZuspitzungen an der Oberfiiiche des Schwammes etwasdichter gehiiuft sind." Their occurrence singly (" vereinzelte ") andnot in longitudinal series, if that is what is implied, is not the usualmode of occurrence of spicules in the fibres of Chalinidas (though itoccurs occasionally in some fibres of Cl(idochalina'), nor is theirgreater abundance in the surface-tufts, so far as I know, usual inthis family. These statements appear to me to point towards thetrue explanation of the nature of these spicules, viz. that they areforeign, and taken in (as is usually the case in Easjyongki) as foreignbodies in small quantities into the surface-tufts. A re-examinationof the original specimen is desirable. If Esper's species is a Chalinid,then the present species is a Easpongia-\sovLioY])\\ oi a Chalinid form,like the Chalinopsid representatives of Siphoiwchalina and Pachi/cha-T-ina which Schmidt (Spong. Meerbusen Mexico, p. 80) has describedas SiphonoGlialinopsis and Puchijchaliiiopsis.I have satisfied myself that another explanation which might besuggested, viz. the dissolution of the spicules from the fibre of theSponge (as in Carter's Aplij^ina chalinoides, afterwards found tobe a true Chalinid), cannot apply to this case. I have studiedthe fibre very carefully, with and without the aid of potash, and canassert that it never possessed "proper" spicules.The respective localities (Cape and Torres Straits) perhaps constituterelative objections to the specific identity of the present withEsper's species.Bab. West Island, Torres Straits.Distribution. Esper's species is from the Cape of Good Hope.3. Euspongia officinalis, Linne, var. cavernosa. (Plate XLI. fig. g.)From a depth of 10 fathoms in Torres Straits we have a smallturnip-like sponge, unfortunately preserved only in the dry state,which to the unaided eye presents the general appearance of a RhizocJmlijia JistuJosa, with several tubular processes, 10 to 35 millim.long and 8 to 10 millim. in greatest median diameter, on its uppersurface ; these processes are, however, ragged in outline at theirdistal ends, and evidently in life opened through the fringed aperture,now obscured by the falling together of the sides ; their sides arein some cases fenesti'ate. The body of the sponge is rudely globular,and is drawn iip above into monticular elevations, which are terminatedby the tubes just described ; the base is somewhat flattened,and has apparently been attached at three points to rock or gravel atthe sea-bottom, portions of which are still left imbedded in the sponge.The chief horizontal diameters of the sponge-body are 45 and 55