380 Mr. H. J. Carter on Specimens 



of this publication, for tlie illustration of one of tlie genera, to be 

 hereafter included in the provisional group " Pluriformia." 



Acantliella stipitata^ n. sp. 

 (PI. XVIII. tig. 8.) 



Head globular, branched, aculeate, supported on a long 

 naked stem. Stiflf. Colour now brownish green. Surface com- 

 posed of aculeations which are the ultimate divisions of the 

 branches, united togetlier bj fenestral expansions of sarcode. 

 Spicule of one form only, viz. acuate, slightly curved or 

 undulating, abruptly sharp-pointed, smooth, 25 by f-1800th 

 inch in its greatest dimensions (tig. 8) ; arranged in bundles 

 in the branched head so as to project a little beyond the 

 sarcode; confusedly in the stem, which is hard and com- 

 pact. Size : — head 2 inches in diameter ; stem, up to where 

 it commences to branch into the head, 2 inches long by 

 l-6th inch thick, much worn and pointed towards the end, 

 which has been broken off from its original point of attach- 

 ment. 



Hah. Marine. 



Loc. Bass's Straits. 



Obs. This sponge differs very little from Schmidt's Acan- 

 tliella acuta (Spong. Adriat. Meeres, p. 75, Taf. vi. fig. 7), 

 except in the size of the spicule, which is about five times 

 smaller than that of the type specimen in the British Museum. 



HOLOEHAPHIDOTA. 



hatrunculia purpurea^ n. sp. 

 (PI. XVIII. fig. 5, a-c.) 



Flat, compressed, circular, thin, cake-like or fungiform, 

 attached on one side by a constricted portion to a ?n?«s5e/-shell; 

 texture compact, but not gelatinous. Hard. Colour dark 

 brown-purple. Surface on the upperside, with which the 

 peduncular portion is connected, ragged, proliferous, much 

 darker than the (?) underside, which is even ; margin thick, 

 round, smooth, like the dark part generally. Internal structure 

 compact, densely spiculous. Spicules of two kinds, viz. : — 

 1, skeleton-, acerate, curved, subcylindrical, gi-adually sharp- 

 pointed, smooth, l-75th by l-4000th inch in its greatest 

 diameters (fig. 5, a) ; 2, flesh-spicule, sceptrelliform, consisting 

 of a straight shaft spined over each end entirely and discoidly, 

 and in two separate rings around the shaft on one side the 

 middle line, the latter often commingled by an irregular dis- 

 position of the spines, about 1-857 ih inch long (fig. 5,b,c). 



