18 Proceedings of the Royal Society of Victoria. 



Esperella rara, n. sp. 



The single specimen is massively lobose, very irregular. 

 Surface irregularly conulose and rugose, with reticulate dermal 

 membrane. Vents small, marginal and scattered. Texture very 

 coarse, with much sand internally, compressible, resilient. Colour 

 in spirit pale yellow. 



Skeleton., composed largely of sand, arranged in coarse, loose, 

 irregular tibres, with no evident cementing substance. The 

 megascleres are very abundantly scattered in the soft tissues 

 between, not arranged in definite fibres but in loose radiating 

 whisps towards the surface. No special dermal skeleton. 



Megascleres., straight slender tylostyli, sharply pointed and 

 with small oval heads ; measuring about 0*23 by 0'00-i mm. 



Microscleres, (a) slender, palmate anisochelse, about 0'02 mm. 

 long, often smaller ; perhaps sometimes isochelre ; {l>) short, 

 slender trichodragmata, about 0'016 mm. long. 



J^.JV. 1108 (x C). 



Genus Esperiopsis., Carter. 



Megascleres always monactinal, smooth styli or tylostyli. 

 Microscleres isochelfe, to which other forms may be added. 



Esperiopsis turbo, Carter, sp. 



Holopsamma turbo. Carter, A.M.N.H., March. 188.-), p. 213. 



Sigmatella turbo, Lendenfeld, Monograph of Horny Sponges, 

 p. 617. 



This sponge is well characterised Ijy its stipitate, pear-like 

 shape, reticulate dermal membrane, skeleton of sandy fibres and 

 greatly reduced spiculation. The megascleres are represented 

 by slender styli, and the microscleres by very minute isochela?, 

 difficult to detect, both of which I have found in a fragment of 

 3Ir. Carter's specimen from the British Museum. 



K.N. 265 (18 f; "dark purplish-ljrown "); 574 (x, 19 f; 

 "brick red"); 6-17 (x, 20 f ; "fawn colour over ferruginous"); 

 1050 (x B). 



B.M. d. 50 (''Holopsamma turbo,'' Reg. 86-12-15-415). 



