47(3 Messrs. S. 0. Ridley and A. Dendy on 



Genus Acarnus (Gray). 



Acuate and cylindrical skeleton-spicules and an ecliinating 

 grapnel-spicule. Flesh-spicules palmate equiauchorates and 

 tricurvates, 



[^Acarnus ternatus, Ridley. 

 Locality. Tahiti, 20 fath.] 



Genus EcHiNOCLATiiRiA (Carter). 



Sponge usually made up of a honeycombed mass of anas- 

 tomosing flattened trabecule. Skeleton reticulate, with much 

 spongin. Skeleton-spicules sraootli acuates or bicapitate 

 cylindricals ; smooth ecliinating acuates commonly present. 

 Minute palmate equiauchorates may or may not be present. 



Echinoclathria Cartertj n. sp. 



Cylindrical, ramose; each branch composed of Hat, ribbon- 

 like, anastomosing trabeculse. Pale yellow. Tough ; very 

 minutely hispid. Spicules: — (1) smooth, sharp-pointed 

 acuates, size '132 by '009 millim. (in and ecliinating the fibre 

 and scattered) ; (2) smooth, very slender subspinulates, size 

 •16 by '002 millim. (scattered) ; (3) palmate equiauchorates, 

 length '015 millim. 



Localities. Station 162, •Bass Straits, 38 fath. ; Station 

 163 a, South-east Australia, 120 fath. ; off Port Jackson, 30- 

 35 fath. 



Echinoclathria glabra^ n. sp. 



Massive, honeycombed. Yellow. Firm and parchment- 

 like, glabrous. Skeleton a reticulation of well-developed 

 horny fibres, sparsely cored by bicapitate cylindricals and 

 sparsely echinated by smooth subspinulates. Spicules : — 

 (1) smooth, fusiform, subspinulate, sharply pointed, size 

 •11 by •0063 millim. ; (2) smooth bicapitate cylindricals, size 

 •22 by '0032 millim. (in the fibre and scattered). No flesh- 

 spicules. 



Locality. Station 162, Bass Straits, 38 fath. 



Genus Agelas * (Duchassaing and Michelotti). 



Well- developed horny fibre, echinated by verticillately- 

 spincd acuates (cylindricals). No other spicules. 



* This genus is inserted here on the supposition that it has had aucho- 

 rate spicules and lost them. 



