178 



"ENDEAVOUR" SCIENTIFIC RESULTS. 



Rhaphidophlls palxispixls, l.cndenfeJd. 



(a) Typical Form. 



(Plate XXV., tig. i ; Plate xxvi., fig. i ; and figs. 36, 36a.) 



1S88. Thalassodendron pancispina, Lendenfeld, Austr. Mus. 

 Cat. Sponges, 1888, p. 224. 



Thalassodendron rubcns, \ar. dura (pars), Lendenfeld, 

 Loc. cit., p. 224. 



Thalassodendron rubens, var. lamella (pars), Lenden- 

 feld, Loc. cit., p. 224, pi. vii. 



1901. Tlialassodendron rubens (pars), W'hitelegge, Rec. 

 Austr. Mus., iv., 2, 1901, p. 87. 



{T. riibens, var. dura; T. yubens, var. lamellosa; T. 

 paucispina), Whitelegge, Loc. cit., p. 87. 



(b) Var. MuLTiPORA, ll'hitelegge. 

 (Plate XXV., fig. 2.) 

 1907. Clathria nndtipora, W'hitelegge, Austr. Mus. Mem., iv., 

 10, 1907, p. 496, pi. xlv., fig. 21,. 



General Diagnosis. — Sponge variable in habit, iiui- 

 flabellar, multijlabellar or ramose; usually attached by a 

 more or less extended disc-like foot, luith or without the 

 intervention of a stalk. In all cases the form assumed is 

 the outcome of a more or less distinctly expressed ten- 

 dency to the restriction of gro7vth to one plane. No osctda. 

 Dermal membrane strongly developed, appearing in the 

 dry sponge as a white pellicle or incrustation. The sur- 

 face exposed by the removal of the dertnal skin is closely 

 dotted 7i<ith pinhole-like punctures. The main skele- 

 ton is a fairly regular, small-meshed reticulation of stout 

 fibres; the main fibres contain a semi-diffuse core, the 

 connecting fibres are short and invariably enclose one or 

 a few spicules. The dermal skeleton is a well-defined 

 reticulation of lines of crowded styli of two sizes, the 

 smaller standing vertically, the larger lying horizontally 

 beneath these and supporting them. Megascleres :- — (/) 

 Stouter, usually slightly curved (principal) styli, chiefly 

 confined to the fibres, varying in maximum size in the 

 different forms from 260 x 9 to J50 .v 16 y,; [ii.) conical 

 tapering acanthostyli, most densely spitted on the basal 

 end, occurrittg sparsely as echinating spicides and scat- 

 tered iti the groutid-sub stance ; length go-ioo p; (/;'/.) 

 slenderer, usually straight (auxiliary) styli (or subtylo- 

 styli) of the same letigth as, or slightly shorter than the 

 principal, occurring horizontally in the dermal metnbrane 



