460 REVISION OF THE AXIXELLUVE. i., 



posed almost solely of spicules. Megascleres, sharp-pointed fusi- 

 form oxea, rarely passiii<f into strongyla, and less rarely into 

 styli; maximum size, iXO x 1*3 /x in the branches, occasionally as 

 much as 530 x 2S// in the stalk. Microstrongyla scarce. 



Loc.—Oa Port Jackson. ("Thetis" Expedition). 



External fratiirfis. — The species is known fi-om a single example 

 (Pl.xxi., hg.4), lOS mm. in total height, c(»nsisting of an elongated 

 slender stalk and irregularly displosed cylindrical branches from 

 2'5 to 4 mm. in diameter. The specimen (wliicli is invested over 

 portion of the exterior by a calcareous bryozoan) is only imper- 

 fectly preserved, having evidently suffered some amount of dessi- 

 cation prior to being placed in alcohol — in consequence of which 

 the dermal layer, while remaining quite intact, has to S(jme 

 extent shrunken inwards upon the underlying skeleton. To 

 this circumstance, in all probability, is largely due the marked 

 degree in which the surface is rendered conulose by the outer 

 ends of the skeletal fibres (PL xxviii., fig. 6): nevertheless, so 

 coarse and stiff are these fibres that, e\en in the best-preserved 

 specimens, the surface would almost certainly show some decided 

 visible effect of their impingement on it, and at least would Ije 

 asperous and harsh to the touch. The conuli aze seldom much 

 above \ mm. in height, very close-set, and of hard feel; they are 

 such that the surface has much the appearance of that of a fine 

 rasp. The dermal membrane is very thin and \eiy closely 

 adherent, accomyiodating itself exactly to the sharply contoured 

 surface-inequalities ; presumably it has undergone considcral)le 

 contraction, since iieither pores nor oscula are detectible. In 

 consistency, owing }jartly to its somewhat dried and shrunken 

 condition, but perhaps mainly to its very dense skeleton, the 

 specimen is tough and hard, almost incompressible; the branches 

 are stiffly iiexible. The colour is brownish-grey on the surface^ 

 and dark brown in the interior.* 



Skeleton. — The prepared skeleton, as sei'n in its entirety (PI. 

 xxiii., fig. 9), is of a faintly brownish, light grey colour, and con- 

 sists of a veiy stout and solid looking core, with coarse and stiff, 

 bristle-like, short radial fibres projecting therefrom on all sides. 



