BY R. VON LENDENFELD, PH.D. 501 



Skeleton. 



The main fibres radiate from the centre of the circular lower 

 side latei-ally and vertically. They are slightly curved in a very 

 regular undulating mannei'. Each undulation measures about 

 1 2 mm. in length and 5 mm. in depth. The main fibi'es are 

 branched in a penicillate manner, and on an average 0*6 mm. apart 

 from each other. They are 0-07 mm. thick, and filled throughout 

 with small sand-grains. Their sui-face accordingly is roughened. 

 The knobs are comparatively high but not very broad, and very 

 close together. 



There are no foreign bodies in the connecting fibres. The 

 meshes of their network measure from 0*1 mm. to 0"3 mm. They 

 are not regular. Extraordinary to say the meshes in the vicinity 

 of the main fibres are larger than those further away from them. 

 Where the main fibres are very close to each other the connecting 

 fibres sometimes are simple, not branched and stand vertical on 

 the main fibres which they connect. The thickness of the con- 

 necting fibres varies from O'Ol mm. to 0'04 mm. 



The only specimen of this sponge is a dry skeleton, so that 

 its position must be somewhat doubtful. No description of the 

 surface, coloui', canal system and histology can therefore be given. 



The colour of the skeleton is a pretty light brown. 



GE0C4r!APinCAL DiSTPtlBUTION. 



North Coast of Australia, Torres' Straits (Macleay). 



Bathymetpjcal Distribution. 

 Probably shallow water. 



II, Sub-Genus. Triplices. 



The connecting fibres in the species referred to this sub-genus 

 are differentiated into thicker tangental and finer radial ones. 

 The former connect the radial main fibres, and are not at all or 

 only very slightly branched, either straight or curved, in such a 



