■438 REVISION' OF THE MOXAXONID SPoNGKS, ill., 



smaller size than this, were present, which contained quite 

 abundant spicules. 



Loc. — Port Jackson. 



Raspailia agminata, sp.n (PI. xxiii., fig.4; and text-tii,'.22). 

 ISSS. II a! ichoud?'ia rubra var. digitata {err.) Lendenfeldl27), PI, 

 ii., fig.l. 



Description. — Sponge a compact tussock-like sessile cluster of 

 erect tapered branches, which combine below into gradually 

 fewer and stouter stems ultimately proceeding from a narrow 

 area of attachment. An adequate idea of the outward form is 

 conveyed by the figure of the single specimen (PI. xxiii., fig.4), 

 which measures 95 mm. in height. The surface is smooth, or in 

 places minutely pustulate; and is sparingly hispid with spicules 

 which project about 1 mm. beyond it. The colour in spirits 

 is greyish-white, and the consistency fairly tough, compressible, 

 and resilient. 



The main skeleton, which is not condensed in the axial region, 

 consists : (i.) of an irregular wide-meshed reticulation of pale 

 slender spongin-fibres echinated, as a rule unilaterally, by moder- 

 ately closely-spaced acanthostyles, the principal fibres of which 

 are cored by pauciserial tylostyli, while the (usually plexus-form- 

 ing) connecting fibres are with rare exceptions aspiculous; and 

 (ii.)of, for the most part, longitudinally-directed styli and tylo- 

 styli lying between the fibres. In sections mounted in balsam, 

 the spongin is scarcely or not at all discernible, and the by no 

 means dense skeleton appears as if composed solely of spicules. 

 An outermost layer of the sponge, which is sometimes as much 

 as 05 mm. in width, though usually much narrower, is com- 

 paratively or quite free from spicules, excepting that it is crossed 

 by the long styli, which hispidate the surface and give support 

 superficially to tufts of small (auxiliary) spicules surrounding 

 the points of exit of these styli. Auxiliary spicules also occur, 

 in very small number, and usually not singly, but in pairs, 

 scattered through the interior. 



Spicules. — (a.) The principal megascleres are partially diflfer- 

 entiated into groups, styli and tylostyli, the latter of which are 

 almost invariably sharp-pointed, while the former are often more 



