﻿SPONGES. KALLMANN. 



247 



taper to a point at a distance from the distal ex- 

 tremity of as much as 15 fi. There is, accordingly, a 

 remote possibility that the spicules belong to two 

 different categories equivalent to the principal and 

 auxiliary spicules of normal Myxillinae ; but inasmuch 

 as the two kinds graduate insensibly the one into the 

 other, and are promiscuously intermingled in the 

 skeleton, whether within the fibres or scattered inter- 

 stitially — it is impossible to arrive at any other con- 

 clusion than that they are but different forms of a 

 single category. 



(ii.) \'ery minutely spined or rugged acanthostyles, 55 

 to 70 it in length and at most 4.5 K in diameter. 



Microscleres. — 



(i.) Relatively stout isochela? palmatae S \i long, mod- 

 erately abundant in the interstitial membranes. 



(ii.) Rare toxa ;l in the few individuals which have been 

 observed, the arms are straight, or slightly reflexed 

 towards their extremities, are inclined at an angle 

 varying from 20° to as much as go°. and vary in 

 length from 40 to 80 ]i, and in diameter up to 3 p. 



Lor.- -East coast of Queensland, nine miles east of Fraser 

 Island, 24-26 fms. ("Endeavour"). 



In many respects W. conecicns so closely resembles Clathria 

 angidifera, Dendy,2 that there is high probability of a near 

 relationship between the two. In the case of the latter it 

 would seem that the non-accessory megascleres comprise both 

 principal and auxiliary spicules, for according to description, 

 they are of two kinds: (a) smooth, straight, gradually sharp- 

 pointed styli (up to about 180 x 4.2 >i in size), occurring in the 

 fibres; and (b) straight styli or subtylostyli (up to about 250 

 ^ 3-5>*)i occurring in the dermal tufts. The opinion which I 

 have expressed that the (non-accessory) megascleres of W. 

 conecicns belong to a single category, is therefore open to 

 question. 



VVlLSOXELLA CURXICHELA, Sp. UOV. 



(Plate xxxi\. , fig. 4; and fig. 51.) 



Sponge stipitate 7vith erect compressed branches. 

 Oscxda small, marginal. Surface even. Dermal mem- 

 brane distinct, thin. Main skeleton an irregular reticu- 

 lation 0/ stout densely echinated fibres; the main fibres 



1 Owing to their rarity these spicules were at first overlooked and wert- 

 thus omitted from the text-figure. 



2 Dendy— Proc. Roy. Soc. Viot.. viii. (n.s.). 1896, y. 32. 



