326 Messrs. S. O. Ridley and A. Dendj on 



Family 1. Homorrhaphidae *. 



Skeleton-spieules acerate to cylindrical ; no flesh -spicules. 



Subfamily i. Renibsina. 

 Spicules never completely enveloped in horny fibre. 



Genus Halichondria (Fleming). 



Skeleton confused ; spicules acerate, long- and slender ; 

 little spongin. 



Halichondria solida, n. sp. 



Massive, incrusting. Greyish yellow. Compact, firm. 

 No special dermal skeleton. Skeleton a confused dense mass 

 of felted acerates ; no fibres. Spicules smooth, curved, fusi- 

 form acerates blunted at the ends ; length up to I'l millim., 

 thickness up to 038 millim. 



Localities. Reefs, Tahiti, 30-70 fath. ; Api, New Hebrides, 

 60-70 lath. (var. rugosa). 



HaJichondria pelUculata, n. sp. 



Erect, lobose, annulated. Vents at summits of lobes. 

 Yellow. Surftice glabrous, covered by a chitinous membrane. 

 Soft internally. Dermal reticulation composed of scattered 

 acerates. Main skeleton sparse, with few distinct fibres. 

 Spicules stout fusiform acerates, curved, sharp-pointed; size 

 •45 by -028 millim. 



Locality. Amboyna, 100 fath. 



Haliclwndria latrunculioides^ n. sp. 



Erect, lobose. Light grey. Soft and spongy internally. 

 Surface corrugated but glabrous ; with rounded pore-areas 

 elevated above the rest. Dermal membrane parchment-like, 

 except in the pore-areas, where it is very thin and reduced to 

 a sieve by the numerous pores. Vents singly on conical 

 processes, chiefly at summit of sponge. Dermal skeleton a 

 continuous sheet of spicules laid side by side. Main skeleton 

 loose, irregularly fibrous. Spicules almost straight, fusiform 

 acerates sharp-pointed, size '7 by "022 millim. ; also a larger 

 form, with unequal ends, size 1'25 by '031 millim. 



Locality. Station 320, off Rio de la Plata, 600 fath. 



Genus Peteosia (Vosmaer). 

 Texture firm to stony. Vents conspicuous. Skeleton 

 * o/^os, one and the same ; pa(p\i, needle. 



