Sponges from South Australia. 461 



general thickness varying under |-6000tli in. Skeletal 

 spicules confined to the head and stem respectively, in wliich 

 the trifid ones of the stem are much larger and stouter than 

 tlie acerates of the head. I could find no anchors or forks in 

 the spiculation of the head or stem either projecting or inter- 

 nally, and the trifid 'ends of the long spicules were only to be 

 seen at the extremity of the root, amongst the grains of sand 

 and shreds of sarcode which firmly held the whole together. 

 Flesh-spicules of both forms mixed together in the head, but 

 not in the stem, where the small one is absent. Size of 

 specimen about 3 in. high, If in, of which is stem ; head 1 in. 

 in its largest transverse diameter. 



Loc. Port Phillip Heads. 



Obs. This sponge, whose root in composition at the extre- 

 mity shows that it had grown in a sandy bottom, very much 

 resembles T. dactyhidea (' Annals,' 1869, vol. iii. p. 15, and 

 lb. 1872, vol. ix. p. 82), chiefly differing from it in the plurality 

 of vents, the consolidation of the stem, and the presence of the 

 large flesh-spicule, together with the corrugated surface of the 

 head, which, not becoming smooth after much soaking, does 

 not appear to have been occasioned by the desiccation to 

 which the specimen had been exposed. The long consoli- 

 dated stem causes this species to take a position in this respect 

 between the sessile forms, ex. gr. T. cranium^ and the stipitate 

 ones, viz. T. ijolyiira^ Sdt., whose stem is composed of a flimsy 

 bunch of more or less separated root-spicules. T. eiqylocamusj 

 Sdt., had a " consolidated " stem and T.jpolyura was covered 

 with bumps (Buckeln), extending into conical processes below 

 (see ' Atlantisch.' and ' Kiiste v. Algier. Spongien,' 1870 and 

 1868, Taf. vi. fig. 8, and Taf. v. fig. 10, respectively). 



List of Mr. J. Bracebridge Wilson'' s Sponges from the Neigh- 

 bourhood of ^^Port Philli2J Heads " and '"'■Port Western^'' 

 on tJie South Coast of Australia^ which have been described 

 and notified resj^ectively in vols, xv., xvi., xvii., and xviii. 

 of the 'Annals ' for 1885-86. 



From " Port Phillip Heads." 

 Order I. Caenosa. 



Halisarca australiensis, vol. xv. Cliondrilla nuciila, Sdt., p. 200. 

 p. 197. 



Order II. Ceratina. 



Lulfaria digitata, vol. xv. p. 201. Pseudoceratina durissima, p. 204, 



Darwinella australieusis, p. 202. crateviformis, p, 205, 



Aplysina leevis, p. 20-4. 



