Sj^onges from South Australia. 511 



spaces clifFerentiated from the cavities of tlie tubulation by tlie 

 presence of reproductive bodies and sarcode, which, especially 

 in the dried state, presents a sponge-brown colour, while the 

 surface of the tubulation is white and without this ; so the 

 two are easily distinguished. The parenchymatous part 

 terminates externally in the thin quasi hbro-reticulate 

 ridges of the surface, where, as before stated, it is traversed 

 by the pores ; but what its connexions internally are I have 

 not been able to determine, although, from analogy, one would 

 be inclined to conjecture that it opened generally by pores 

 and here and there by small holes (the latter probably for the 

 exit of the reproductive bodies) into the cavity of the tubula- 

 tion. On the other hand, the tubulation opens on the 

 surface through the small and large vents, that is the former 

 directly and the latter after having come from more dilated 

 portions in the centre of the mass ; but all appear to be more 

 or less in communication. Spicules of one form oidy, viz. 

 triradiate, equiarmed, equiangulated ; ray about 35 by 3- 

 6000ths, varying in size under this with a few a little larger : 

 densely charging the sarcode throughout, but especially on 

 the surface, which is thus rendered a little more compact than 

 the interior, so as in some specimens to present a cortical 

 structure. Size of largest specimen, of wliich there are 

 several, about 4 inches in diameter each way, being cubical. 



Ohs. In this species we cannot help seeing that the paren- 

 chymatous structure which intervenes between the contorted 

 tubulation presents a still further step than in Clathrina 

 laminoclathrata towards that which reaches its maximum in 

 the Leucones and TeichonellidiB, as will be seen hereafter ;' at 

 the same time that the dilated portions of the tubulation in the 

 midst of the mass, in communication more particularly with 

 the large vents externally, appear in the aggregate to be 

 tantamount to a single cloacal cavity with general osculum ; 

 while the spaces occupied by the parenchyma appear to be 

 the seat of Hiickel's " intercanal system," that is, the inter- 

 spaces between the " radial chambers " in Grantia ciliata &c. 

 In the large specimen of this species, viz. that described, 

 there are also ova^ but apparently scanty and in a more 

 advanced stage, mixed up with minute crustaceans, which 

 would hardly be there if it were not for the presence of the 

 sponge-ova, for it is at this time that they more particularly 

 invade most destructively the calcareous sponges ; hence it is 

 not improbable that some of the ova may be theirs, which 

 prevents my being able to say what the sponge-ova are like. 

 But there is anotlier body also scantily present which is quite 

 new to me, but, being more plentiful in the following species, 



