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

SPONGIIDA. 621long, from those of the latter in the greater relative stoutness ofthe basal end and in their superior length (about twice that offenestratus).43. Leucophlceus fenestratus, var. (Plate LIII. fig. A.)See Part I., p. 464, of this <strong>Report</strong>.A spirit-specimen and some fragments, combining the externalcharacters (viz. erect, laminate, with the upper portion echinatedby fine upwardly directed processes, and with smooth, thick basalportion) of Leucophlceus proteus, mihi, with a spiculatiou of thecharacter of L. fenestratus. The outward form of these two speciesis, however, essentially the same, and the differences observed inthis point are mainly individual. The present specimen, linkingthe Australian to the more, western form, has decided a doubt whichI had as to the rightful position of the former species in the genus.The specimen is young, measuring 5U millim. (2 inches) in height by(including a fragment which appears to belong to it) 35 millim. ingreatest diameter (that of the base).It consists of a massive basalportion, enclosing a large quantity of calcareous matter (Nullipore,&c.), and of a slender flattened expansion, 20 millim. high, 10 millim.broad, 4 millim. thick, arising from it ; the base is glabrous, the surfacebeing formed by a thin, transparent membrane, loosely attached.Main skeleton consisting of compact spiculo-fibres about 10 spiculesbroad, and of broad expansions containing a large number of spiculesloosely aggregated. There is no sign of horny uniting substance.Spicules tapering gradually from near the centre, or about midwaybetween the centre and base, to a smaller rounded basal extremity,which is about one half the maximum diameter of thespicule ; spicule tapering rapidly to moderately sharp point from twoor three diameters from apex; size of spicule -8 to 1-1 millim. bv•02 to -032 millim. (a considerable range for only two or three specimens).The spicule has thus practically the same form as in boththe Australian varieties, and in its range ot dimensions connects thetwo. The colour, which is purple, as in L. proteus, but pale, ispossibly derived from some purple sponges which had been kept inthe same vessel.Hab. Providence Keef, Mascarene group, 24 fms.SUBERITID^.The few species received illustrate well the wide affinities ofSponges from this district. Tethya, s. str., which was not found onthe northern and eastern coasts of Austraha, but which is recordedby Bowerbank from the west coa^t, appears here also, in the shapeof a species described by Bowerbank from Freemantle. Of the twonew species of S/nrasirella, IS. transitoria appears to throw freshlight on the homologies of the spinispirular spicule. The Vioais identical with a Mediterranean species.