KiKK. — S/)(>ii(/rs roJJcrfcd at ihc Kirnutder hJandn. 



511 



polygonal network, the meshes of whieh are broken up by finer, irregular 

 fibres of light colour. Spicules are never polyserial in the dermal skeleton, 

 and are more numerous in the secondary fibres. Many lie outside the fibres. 



Spicules are all oxea, straight or slightly curved, running somewhat 

 suddenly to a fairly sharp point. Size, 0-05 mm. by 0-004 mm. 



This sponge appears to be close to Dendy's C. clathrata (IV, p. 151) 

 and to Topsent's C. similis (X, p., 481). 



A single dry specimen received. " Cast up on Denham Bav beach, 

 Sunday Island ; 27/7/08." 



Genus Toxochalina Ridley. 



Ridley (VII, p. 402) founded the genus Toxochalina for " Chalinidae with 

 well-developed horny fibre arranged rectangularly. Spicules, a skeleton 

 acerate and a tricurvate acerate (' Bogen ') flesh spicule." 



One of the Kermadec Island sponges is a Ghalina in every respect of 

 structure, except that it has minute flesh spicules in the form of oxea. In 

 view of the fact that many of the Chalininae have been described from 

 beach-worn specimens, and some of them may yet be found to possess flesh 

 spicules, it seems unwise to establish — at present, at all events — a new genus 

 differing from Toxochalina only in the form of its microscleres. I there- 

 fore suggest a slight emendation of the generic character to admit sponges 

 differing from Chalina in the presence of simple linear microscleres. 



Toxochalina oliveri n. sp. Fig. 4, and Plate XXVII, fig. 2. 



Sponge attached by the greater part of the lower surface. Oscula pro- 

 minent, on the summit of rounded elevations on the upper surface, or on the 



crest of level ridges formed by the 

 concrescence of such elevations. 

 Colour yellowish-buff. Texture 

 firm. Length of specimen, 

 9-5 cm. ; width, 6 cm. ; height, 

 1-5 cm. 



Structure of skeleton : Primary 

 fibres running in parallel or in 

 radiating lines to the surface, 

 connected by .the secondary 

 fibres, which form with them 

 and with each other rectangular 

 meshes. The primary fibres 

 contain an uneven strand of 

 oxea loosely and irregularly ar- 

 ranged, most numerous at the 

 nodes. The strand thins out in 

 places to the point of disappear- 

 ance, but usually it consists of 

 about six series of spicules. 

 Secondary fibres thinner than 

 the primary, containing few 

 spicules, and these not poly- 

 serial and not in contact end to 

 end. The general appearance 

 of a section of the skeleton is very like that of Siphonochalina procumbens 

 as figured by Dendy (III, pi. 58, fig. 4). In the dermal skeleton the meshes 

 are subdivided by finer fibres (fig. 4, 2). 



19— Trans. 



Fig. 4. — Toxochalina oliveri. 

 Section of skeleton at right angles to surface. 

 2. Portion of dermal skeleton. 3. Oxea. 

 4. Microscleres. 



