﻿164 



•ENDEAVOUR" SCIENTIFIC EESULTS. 



Foreign bodies, chiefly large sand grains, occur at usually 

 irregular intervals in the fibres, and sometimes in small 

 patches in the ground substance. Different specimens exhibit 

 considerable differences in regard to the amount of foreign 

 material included. The ground substance is densely strewn 

 with megascleres which consist almost en- 

 tirely of accessory acanthostyles. The dermal 

 skeleton is for the greater part a well-defined 

 reticulation of acanthostyles with poly- 

 gonal (usually fi\e or six-sided) meshes, but 

 in places (particularly on the margin of the 

 sponge) the spicules become so closely packed 

 that the insterstices of the meshwork are 

 almost, if not entirely obliterated. Oxea 



are absent from the dermal skeleton. 



Fig. 32 — C. 171- 

 cnistatis var. are- 

 nacea. a Princi- 

 pal acanthostyle. 

 b Dermal acan- 

 thostyles. c Iso- 

 chela arcuata. 



Megascleres.— 



(i.) The oxea vary in length from about 

 160 to 200 \i\ the stoutest are 7 or 

 (rarely) 8 ^ in diameter. 



(li.) The principal acanthostyles reach a 

 maximum size of 160 x lo-ii \i. 



(iii.) The dermal acanthostyles \arv in 

 length from 65 to no \i, or e\en 

 slightly longer ; the}' are usually 

 between 75 and 100 \i in length; 

 acanthoxea occur among them as 

 rarities. The longest are usually 

 straight spicules with slightly re- 

 curved spines and more closely 

 resemble the principal acanthostyles 



than is usually the case. The stoutest are about 



8-9 }i in diameter. 



Micro scleres. — 



The chela?, which are about 12 to 18 /i long, show no 

 appreciable separation into two groups. 



Locs. — Port Phillip, Victoria {Carter, Deudy, Austr. Mus. 

 Coll.); southern coast of South Australia, eleven miles 

 N.N.W. of Cape Martin, 21 fms. ("Endeavour"); eastern 

 coast of New South Wales (Austr. Mus. Coll.). 



Crf.i.i.a ixcrustans. Carter, var. Levis, Lendejifeld. 



(Figs. 33, 34.) 



1888. Echino)iei)ia levis, Lendenfeld, Cat. Sponges Austr. 

 Mus., 1888, p. 220. 



Echinonema rubra, Lendenfeld, Loc. cit., p. 221. 



