POEII-'IJRA OF THE L.M.B.C. DiSTKlCT. '2()9 



(0-3— 0-53 mm. by 0-012 mm.) and spined styli (0-148 

 mm. by 0008 mm). The former generally spring from 

 the inner portions of the fibres, and at less acute angles 

 (about 25°), whilst the spined styli have their bases more 

 in the outer portions of the fibres and spring at greater 

 angles (about 50") from the fibres. There are also two 

 kinds of microscleres — toxa (0-124 mm. by 0*002 mm.) and 

 extremely minute chelae (0-012 to 0-016 mm). The micros- 

 cleres are irregularly scattered through the tissue between 

 the ascending fibres. 



A very brief description of this species has also been 

 given by Carter.* 

 Aj'inella mammillata, n. sp. (PL X., figs 3 — 5). 



I was doubtful for some time in which genus of the 

 family Axinellidse, the new sponge described below, should 

 be included. At first I was rather inclined to make of it 

 a new species of RaspaiUa, Nardo, but as Eidley and 

 Deiidy t propose to reserve the genus RaspaiUa exclusively 

 for the whip-like forms, I decided to place the new sponge 

 under the genus A.cinella, Schmidt, t Still in doing so I 

 do not feel great satisfaction, as the genus A.cinella seems 

 at present to be a receptacle for all iVxinellidae which do 

 not belong to the more clearly defined genera : Hijmenia- 

 cidon, VhihelUa, Clocabjpta, Acantliella, RaspaiUa, Dendropsis, 

 and Thrinacophom. Ridley and Dendy say, in regard to 

 the genus A.vinella, " Sponge typically ramose, but may 

 be massive. Skeleton fibre plumose. Megasclera stylote 

 and sometimes oxeote. No microsclera. This is a very 

 critical genus, and it is impossible to give a satisfactory 



" Carter, "Annals and Mag. Nat. Hist.," fourth ser., vol. xvi., p. 195, 

 and fifth ser., vol. vi., p. 40. 



t Ridley and Dendy, "Report on the Monaxonida, collected by H. M.S. 

 ' Challenger,' " p. 178 and p. 188. 



X Oscar Schmidt, " Spongien des Adriatischen Meeres." 1862, p. 60. 



