IG Proceedings of the Royal Society of Vtctoria. 



Skeleton. The main skeleton is a very irregular network of 

 stout fibre, usually containing many spicules bound together by 

 much spongin, often also containing much sand or broken 

 spicules. Numerous megascleres are scattered in the ground 

 substance. The dermal skeleton is a rather close reticulation of 

 spicular fibre, echinated by abundant projecting spicules. 



Megascleres, slender styli or tylostyli with feebly developed 

 heads ; gradually sharp-pointed at the apex ; measuring about 

 0-158 by 0-0027 mm. 



Microscleres, (a) slender palmate anisochelse, scattered singly, 

 about 0'025 mm. long and with narrow palm, of ordinary form ; 

 (d) some specimens contain a few slender, contort sigmata, about 

 0-066 mm. long from bend to bend. In many specimens there 

 are scattered through the ground-substance, millions of minute, 

 ovoid, highly refractive, very definite bodies, measuring about 

 0-0083 mm. in length. These occur in such numbers as to 

 impart a peculiar opaque appearance to the whole sponge and 

 also to sections. I do not at present understand their true 

 nature. 



This is a very unsatisfactory species, owing to the absence of 

 constant and well-defined characters. 



J^.JV. 280; 292; 350; 363; 372; 396; 408; 472; 525; 578; 

 579; 581; 588; 603; 648; 749; 805; 941; 968; 990; 1152; 

 1190; 1194. 



EspercUa arenicola, Ridley and Dendy. 



Esperella nrenicola, Ridley and Dendy, Challenger Monaxonid;i, 

 p. 72, pi. XV., figs. 4, 4a ; pi. xvi., fig. 8. 



This species, already obtained by the Challenger from Bass 

 Straits, is represented in the collection by two specimens from 

 the Queenscliff jetty, wliich agree very closely with the original 

 type. 



R.N. 689 ; 693. 



Esperella ioxifer, n.sp. 



Sponge massive, sessile, spreading, irregular. Surface uneven 

 but subglabrous. Vents small, scattered on upper surface. 

 Texture extremely soft and spongy, coarsely fibrous. Colour in 

 spirit pale yellow ; in life " wax ochre." 



