674 REVISION OF THE AXINELLID^E, ill., 



(g.n.), ^iem?t« (including AUantophora), Sigmaxiiie/la, Sigmaxia 

 (g.n.), CeratopsU, D)a(jm<ixia( g.n.), DrogniacidonI g.n.), Axidrag- 

 77ia(g.n.), Dragmalelli I, {g.n.), Thrinacophora, Dragmatyle, and 

 Rhaphoxya (g.n.). 



Tlie occurrence of trichodragmata in Rhizaxmella pyrifera, — 

 which, according to Topsent(51), is identical with R. clavigera 

 Keller, the type-species of Rhizaxinella, — and in Spinularia 

 spimdaria (^ Nhaphidoi us setosus Topsent*), renders it possible 

 that these species are more nearly related to the Desniacellinai 

 than to the Suberitidte and Polyinastiidje respectively. 



The two species described by Ro\v(34) under the names Ophli- 

 taspo7igia(l) arhuscula and 0.(1) horrida, which certainly do not 

 belong to Ophlitaspongia, are perhaps representative of a new 

 genus related to Tylodesma. Another species which it may be 

 necessary to include in the Desmacellinpe, under a new genus, is 

 that described by Kirkpatrick(22) as Ophlitaspongia nidijicuta. 



The genus Siymaxinyssa Kirkpatrick(22) I regard as belonging 

 to the Gelliinaj. 



The genera Trachygellitis Siud Spirasigma, established respect- 

 ively by Topsentt and myself (12, p.l31, footnote) for Trachya 

 glohosa Carter, and for Gellius aculeatns Whitelegge, are ob- 

 viously related to the Tetillidas, and must, I now think, in spite 

 of their apparent non-possession of tetracts, be included in that 

 family. The chief distinction between the two genera is the 

 presence of small, spinulous oxea in the latter (cf . Tetilla uus- 

 traliensis) and their absence in the former. In both genera, the 

 sigmata (sigmaspires) are very finely spinulous. The genus 

 Spirasigma is identical with that indicated by Lendenfeldj by 

 the name Suberamata. 



At the last moment, after having corrected the proof-sheets 

 of Part iii., I find that two species, which apparently must be 

 added to the Desmoxyinse, have been described by Kel]er(18, 19) 

 under the names Axinella pumila and Tracliytedania arhorea. 

 The former of these may be referred, provisionally at least, to 



* Vide Stephens, "Fisheries, Ireland, Sci. Invest., 1914, iv.(1915)," p.30. 



t Topsent, E., M(^m. Soc. Zool. France, vii., 1894, p.8. 



J Lendenfeld, R., Zool. Jahrb., ii., 1887, p.564. 



