638 REVISION OP THE AXlNELLID^E, iii., 



oxea; there is no special dermal skeleton. The niegascleres are 

 of the two forms mentioned, which are quite distinct in kind. 

 The microsclei'es are trichodragmata accompanied ur not by 

 single trichites. 



Type-species, A. padiiia Topsent(47). 



This genus is proposed for the reception of Topsent's Axinella 

 jxidiiia, described from the Gulf of Lyons. At first I was 

 inclined to include the species in the genus Drmjniaxia, with the 

 single species of which it presents some striking points of super- 

 ficial similarity ; but consideration of the decided differences 

 between it and the latter in the matter of skeletal structure has 

 confirmed me in the view that their generic separation is ad- 

 visable. As regards the precise structure of the skeleton in 

 Axhiella 2xidina, however, Topsent's description is not very 

 explicit, and a quite exact definition of the genus caimot there- 

 fore be framed. In speaking of the outward features of the 

 sponge, he mentions that the single specimen, in consequence of 

 its having been somewhat damaged by the trawl, "se trouve en 

 plusieurs endroits use et perce a jour: de la sorte se trouve mise 

 a nu par place I'espece de nervation qui monte en eventail du 

 pedicelle jusqu'au bord des lobes, en lignes spiculeuses, epaisses, 

 nombreuses et, par suite, a peine divergentes." And further on, 

 in describing the spiculation (which consists of slightly curved 

 styli, 650 to 900/x in length by 8 to 10// in diameter at the base, 

 and of curved, sharp-pointed oxea with a maximal size t)f 275 by 

 6/1.), he merely adds that the styli "forment les nervures et 

 determinent I'hispidation de la surface", and that the oxea "con- 

 stituent les lignes secondaireti ordinairement unispiculees de la 

 .charpente". It is not clear whether the "nervures" are of the 

 nature of funes, or whether they are formed Ijy single fibres; nor 

 is any mention made as to whether or not the fibres are plumose, 

 nor regarding the extent to which spongin is developed in con- 

 nection therewith. It is presumable, however, that the "lignes 

 secondaires" are of the nature of connecting fibres, and that the 

 styli producing the hispidation of the surface are the terminal 

 spicules of fibres running outwards to the surface. 



