SPONGES— WHITELEGGE. 497 



Microscleres : — (1) Angular clielse ; size 0-024 mm. (2) Bow- 

 shaped toxa ; size 06 mm. 



Four specimens were obtained off Botany in from 20 to 23 

 fathoms. 



CLATHRIA(?) CHARTACEA, sp. nov. 



Stations 41, 44. 



Sponge arising from a discoidal base, with a well developed 

 compressed peduncle ; the lamina is thin, paper-like, and may 

 consist of a flabellate frond or a number of strap-shaped expan- 

 sions. The largest example obtained b}^ the " Thetis " measures 

 224 mm. in height, and 60 mm. in its broadest part ; from thence 

 it gradually narrows to the somewhat alate footstalk ; the lamina 

 rarely exceeds about 1 mm. in thickness except near the base. 

 A specimen from the beach at Middle Harbour consists of a 

 short stout pedicle and three narrow fan-shaped lobes ; the 

 measurements ai-e as follows : — height 227 mm., total width 337 

 mm. The various lobes are about 60 mm. in breadth and are 4 

 or 5 mm. in thickness at the base, but they rapidly become 

 thinner towards the very acute margins. 



Dermal surface minutely porous, apparently smooth, but harsh 

 to the touch, with faint indications of a white incrustation due 

 to the radiating tufts of the stout styli of the ends of the fibres 

 and the slender styli of the epidermis ; oscula absent (?). 



Texture thin and parchment like, r<^silient, and somewhat 

 tough in spirit, but brittle when dry ; colour yellowish-grey. 



The skeleton is remarkable for its stout horny fibres, which 

 are arranged in close subparallel lines running from base to 

 summit. The primary fibres are very evident by transmitted 

 light in a much worn specimen ; they are subcontinuous from 

 base to apex, and exhibit frequent dichotomous branching, with 

 numerous slender secondaries connecting the main fibres. 



The general appearance is like some textile fabric with strong 

 longitudinally arranged threads, and connected at regular inter- 

 vals by very slender processes, which are disposed at i-ight angles 

 to the main fibres ; the latter are from 0-25 to 05 mm. in 

 diameter, and about the same distance apart. The secondaries 

 and connecting fibres are generally about 0"i or less in diameter 

 and 0-4 apart. The mesh is more or less subcircular, but fre- 

 quently obscured by the echinating styli, which are arranged iu 

 a sort of confused Renieroid fashion throughout the sponge. 



The primary fibres are cored with a few scattered smooth .styli ; 

 the secondaries are bi- or trispicular, and at tlie surface the latter 

 tei-minate in tufts of three or four stout styli, and are intermixed 

 with long .slender cylindrical subtylostyli with a short acute apex 

 and a slightly spiny base. 



