SPONGES WHITELEGGE. 499 



(2) Straight smooth styli, chiefly dermal, but also scattered in 

 the choanosome ; size 0-13 to U-2 by 0"008 mm. 



(3) Large smooth styli, of the main fibres, generally more or 

 less curved, and gradually tapering to long acuminate points : 

 size 0-3 by 0-01 to 0-015 mm. 



Microscleres : — (1) Slender toxodragraata, rather abundant; 

 size 0-07 to 0-12 by 0-U02 mm. 



(2) Strongly bent toxa, scarce; size 0-035 by 0-0015 to 0002 

 mm. 



(3) Isochelee with a nearly straight shaft and long flukes which 

 almost meet at the ends ; size 0-018 mm. 



(4) Very small isochelte ; size 0-008 to O'Ol mm. 



The above species is closely allied to Clathria typica, Carter, 

 sp., but on comparison with many examples from Victoria it 

 appears to be quite distinct ; the spicular characters enumerated 

 above separate it from any other species known to or examined by 

 the writer. 



CLATHRIA CALOPORA, sp. nov. 



(Plate xlvi., fig, 34.) 



Station 50. 



Sponge consisting of a series of knotty cylindrical branches ; 

 the branching is either dicliotomous or lateral, and coalescence is 

 evident in some parts. The specimen is 195 mm. in height, and 

 the branches vary from 3 to 8 mm. in diameter. Surface hispid, 

 reticulate, finely porous throughout ; the pores are mostly circular 

 and about 1 mm. or less in diameter; the whIIs are thin, promi- 

 nent, and minutely conulose, presenting a minutely honeycomb- 

 like sux'face without any distinct trace of dermal incrustation. 



Texture hard, inelastic, and rather tough ; colour greyish- 

 yellow. 



Skeleton consisting of stoutish horny fibres, which are densely 

 clothed with short but very spiny echinating spicules ; the axial 

 core is slender, and has from 3 to 6 spicules in a row, the apices 

 of which are more or less divergent, Near the surface a number 

 of slender styli occur, some of which run parallel to the stout styli 

 of the core, and at the surface they are either arranged at right 

 angles or form a thin layer and occasional radiating tufts. Long 

 slender sinuous toxa subtend the fibres, especially in the curves 

 of the mesh ; some few exhibit a very slight well rounded bend 

 in the middle, but the majority are arranged in wavy bunches. 



The primary fibres are sinuous and often plexoid, in some 

 places they almost form a complete horny core ; they are usually 

 from 0-2 to 0-4 or more in diameter ; the secondaries are given 

 off at an acute angle, and after traversing the axial line for a 



