Sponges fro)a South Australia. 37 



arranged around the external ends of the radial chambers to 

 which they belong. 2, triradiates, varying in size and shape 

 according to their position, that is from an equiangled to a 

 sagittal form in which the arms are much expanded. 3, quad- 

 riradiates, whose fourth arm is short, curved towards the 

 mouth, and projects into the cavity of the cloaca. No. 1 in 

 its thin form is confined to the peristome, and in its stouter 

 one to the tufts on the surface of the body, mingling also with 

 the proximal ends of the peristome-spicules ; no. 2 chiefly to 

 the spicular skeleton of the radial chambers, which is thus 

 '^ articulate ; " and no. 3 chiefly to the cloaca, where its 

 fourth arm thickly echinates the surface and circular holes of 

 this cavity. Size of largest specimen, of which there are two^ 

 1^ in. long by 4-12ths in. in greatest diameter, which, the 

 specimen being pyriform, is towards the free end ; vent or 

 mouth about ^ in. in its greatest diameter. 



Ohs. This species, although closely allied to OranUa. 

 ciliata^ differs from it in several particulars, viz. first in the 

 pore-areas -being much more circularly defined, arched out- 

 wards, and presenting a stelliform appearance ; secondly, in 

 the radial chambers being of the same size throughout, while 

 in Grantia ciliata they widen outwards ; and thirdly, in two or 

 more openings of these chambers opening inside the holes of 

 the cloaca respectively, while in Grantia ciliata each chamber 

 has its appropriated opening in the cloaca, and each is spliinc- 

 tered by a sarcodic diaphragm. The smaller specimen is 

 charged with ova about 1 -400th in. in diameter when dry, 

 which possess the germinal vesicle and now are evidently 

 on the surface of the radial chambers as much as in the paren- 

 chyma, where they are also present. 



With reference to the position of the ova, they must be 

 developed ah initio from the surface of the chamber or tube 

 in some instances, as in the Clathrince^Q-s.. gr. C. osculuni &c., 

 where the internal surface of the tubular thread of which 

 it is composed is plentifully charged with them ; since here 

 there can be no " parenchyma," for there is no place for it. 



11. Grantia compressa^ auct. 

 The specimens of this species have grown on a small 

 feathery Fucus in much the same condition as they grow here 

 (Budleigh-Salterton, S. Devon). 



12. Grantia conipressa, vnY.Jistulata. 

 The only difterence between this and the usual compressed 

 form of G. compressa is that it is tubular : it grows in a bunch 

 contracted to tlie point of attachment, in which the individuals 



