BY E. F. HALLMANN. 277 



"the skin " of the sponge. Aecordinirly, taking everything into 

 consideration, I think one is justified in regarding 7V///ya injiatd 

 (like T. corticata) as a synonym of D. inyaUi var. Ifi'vis. 



Tetrya phillipensis. (Plate xv.. fig. 4). 



Two of the three specimens labelled as the types of Tethya 

 phiUipensis, although by no means closely in accord with the 

 description of this species, yet exhibit so many analogies there- 

 with as regards both external and skeletal features, that one is 

 justified, I think, in accepting them as the types of the species. 

 The third specimen, while perhaps more closely in agreement 

 with the description in the matter of skeletal chai^acters, differs 

 from the other two in surface-features, and pi'ovisionallv I do not 

 regard it as belonging to the same species as they. The locality of 

 all three is given as Port Phillip, and this is confirmed, as regards 

 the two taken to be the types, by the occurrence of a similar 

 sponge in a collection from Port Phillip presented to the Austra- 

 lian Museum by the late Mr. J. Bracebridge Wilson. The fol- 

 lowing brief description, based on the two type-specimens and 

 the one last-mentioned, will be sutiicient to show that T. phillip- 

 ensis is well distinguished from any other of the forms of Donatia 

 herein described: and, at present, I consider it to be an inde- 

 pendent species. As contrasted with D. ingcdli, to which it 

 makes nearest approach in spiculatiou, its chief diagnostic 

 features are the minute pattern of the surface, the presence of 

 (a few) spheres in addition to asters of three kinds, and the 

 plentiful occurrence of spherasters in the choanosome. 



The sponge is of more or less globular shape, either sessile (and 

 then at times somewhat depressed) or prolonged below into a 

 short stalk-like portion (i.e., somewhat pyriform). The oscula 

 are conspicuous and several in number. The colour in alcohol 

 varies from a pale creamy-white, with a tinge of pink, to a light 

 salmon. The surface, which is fairly regularly tuberculate, shows 

 over its entire extent a minute reticulation (just visible to the 

 naked eye): the tubercles are usually much depressed, flattened, 

 and the surface as a consequence presents a slightly tessellated 

 appearance. The shallow and, for the most part, narrow grooves 



