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

;'SPONGIIDA. 619spicular columns radiating horizontally from the axial skeleton, butmuch disguised by crossing spicules, sometimes united into secondaryfibres. Axial skeleton—the longitudinal lines strong, but in basalparts of sponge confused by close aggregation ; the axis of the flabellateparts is composed, on the contrary, of a dense mass of horizontallyarranged spicules, from which the short dermal tufts projectso as to appear on the surface of the sponge. Bases of spicules ofradiating lines and much of the entire axial spicular columnsenveloped in a tough transparent substance, amber-yellow in dry,salmon-colour in spirit-specimens.Spicules :—(1) Acuate, smooth, curved slightly but rather abruptlyat from one third to one half the distance from the base ; taperinggradually from about middle, more rapidly from about three fourthsof length, to sharp points, and sometimes slightly towards basebase rather squarely rounded ; size '55 by '032 to -O-iS millim.(forms chief part of the axial and radial columns and the secondaryfibres). (2) Acuate, smooth, straight or slightly curved, taperinggradually to fine points from about one fourth of the length fromthe apex ; base well rounded : size -5 to 1-8 by '015 to -02 miUim.(sparingly, in company with no. 1, in most parts ; especially, attachedto bases of radiating columns, and projecting outwards in a directionparallel to them).Hab. Providence Island, Mascarene group, 18 and 19 fms. ; bottomcoral.Two small specimens in spirit, one large dried dredged specimen,and two medium-sized beach-worn specimens represent the species ;the largest measures 120 millim. (5 inches) in both greatest heightand lateral extent ; the stem is 20 millim. in greatest lateral by8 millim. in greatest antero-posterior diameter. The species hasmuch of the external appearance of Spongia carduus, Lamarck, ofthe Paris Museum, the spiculation of which, however, refers it toanother genus. It difiers from all the species described by Schmidtfrom European and W.-Indian seas in the absence of an aceratespicule; in the great stoutness of the main acerate it approachesA. mastopliora of that author, from Florida. In general habit itresembles Acanthella rather than AxinelJa, but wants the longundulating cylindrical spicule hitherto found in species of thatgenus ; it appears doubtful whether the existence of such speciesas this should not induce us to unite the two genera. I have beenunable to identify it with any described species ; the large stoutacerate appears to be the most distinctive characteristic.LEUCOPHLffiUS.Carter, Ann. 8f Mag. N. H. 1883, xii. p. 323.In its affinities this genus appears to be Axinellid ; it is distinguishedfrom Axinella, s. str., by its loose yielding texture, theskeleton- fibres being loosely united, but containing a dense keratose