208 Transactions. — Zoologij. 



according to my present view, the separation of the two forms, 

 much as they appear at first sight to differ. 

 Locality : Cook Strait. 



Leucosolenia intermedia, n. sp. (Plate lY., fig. 2.) 



Sponge compact ; yellow or yellowish-white when alive. 

 Oscules numerous, each one at the apex of a small conical 

 papilla: they often become obscured at death. There is a 

 well-marked pseudoderm, characterized by stout tripod 

 spicules. The spicules are all triradiates. 



Sjoiculcs : — 



The rays of the stout, pseudodermal spicules are strongly 

 incurved, and are of about the same length as those of the 

 deep spicules ; they are blunt. The spicule forms a massive 

 tripod, stouter than that of L. tripodifera, and with the 

 rays a little more widely spread. Viewed from below, in 

 certain positions the efl'ect of perspective is to give a sagittal 

 appearance that is illusive (figs. 2r/-2/). A few stout 

 3-radiates are regular, and have straight rays (fig. 2a). Size, 

 0-18mm. X 004 mm. 



The spicules of the deep parts of the sponge are regu- 

 larly-tapering 3-radiates, with fairh- sharp points. Size, 

 0-09mn]. x O'Olmni. The canal system is of Dendy's type E. 



In spiculation this sponge occupies a position intermediate 

 between L. jndcherrina and L. "proxima. From the former it 

 is broadly distinguished by the fact that its pseudodermal 

 spicules are larger instead of smaller than its deep ones, and 

 from the latter by the marked tripod character of the pseudo- 

 dermal spicules. This last characteristic seems also to dis- 

 tinguish it fiom L. stipitata. 



Locality : Cook Streit. 



Leucosolenia laxa, n. sp. (Plate IV., fig. 1.) 



Texture loose ; colour white. A pseudoderm, characterized 

 by oxeote spicules, is present, but is not well developed except 

 at the sides of the sponge. Mesodermal ingrowths occur 

 sparingly, aiid they may or may not be covered by collared 

 cells. Skeleton consisting of 3-radiate, 4-radiate, and oxeote 

 spicules, the two former occurring throughout the sponge, and 

 the last being confined to the pseudoderm, and echinating 

 feebly the surface of the sponge. 



Spicules :— 



Triradiates : Eegular ; rays tapering evenly to a sharp 

 point; 0-17mm. x 0015nmi. 



Quadriradiates : Basal rays sometimes slightly curved, ta- 

 pering evenly to a sharp pomt, 015mm. x O'OlSmm. ; apical 

 ray straight, O'lmm. x 0"013mm. 



