﻿132 



"ENDEAVOUE" SCIENTIFIC KESULTcs. 



Genus Paracordyla, gen. nov. 



The inner skeleton is a dense columnar aggregation c} 



large oxea which, in linear outgrowths of the spon(^~- 



hody [if these be present), takes the form of a very c^^m- 



pact axial core. Spongin appears to be wholly absent. 



The ectosomal skeleton is a dense palisade of I'ertical 



microxea supplemented by ''dermal briishes^' of styli or 



oxea. Between the ectosomal layer and the inner 



skeleton-mass is a narrow zone penetrated by canals and 



crossed by strands of the large oxea. In addition to 



microxea, microscleres in the form of small amphiasters 



are present. 



The spiculation of this genus is remarkably similar to that 



of Scolopcs moseleyi, Sollas ;1 but since Sollas speaks of fibres 



in connection with his species, and remarks that the 



general character of its skeleton reminds one forcibly of that 



in Carter's genus Trachya, there is evidently a distinct generic 



difference between Paracordyla and Scolopes. Amongst the 



Axinellida^, the genus which makes the nearest approach to 



Paracordyla y appears to be Ceratopsis, Thiclc^ 



Paracordyla i.igxka, sp. iiov. 

 (Plate xxii., fig. 2, and figs. j6, 27.) 

 Sponge sessile, with a massive body from wJiich 

 branch-like elongations may arise. Consistency, owing 

 to tJie enormous development of the spicules, very dense 

 and solid. Surface even, pilose. Oscula wanting. The 

 skeleton of the ivhole of the inner mass of the sponge to 

 within a few millimetres of tJie surface is formed of closelv 

 aggregated large oxea, with a general parallel arrange- 

 ment, ivhich, in the branch-like parts, form an almost 

 solid core. Between the core and the superficial layer 

 (cortex) is a )tarrow zone, 2 to _? iiim. wide, crossed by 

 strands of similar oxea, the outer spicules of which pro- 

 ject well beyond the surface. The surface is also pro- 

 tected by bruslies of shorter spicules varying in form from 

 styli to oxea. The canals of the subcortical zone are 

 surrounded by radially disposed microxea, and similar 

 spicules, together zvith minute amphiasters, are scattered 

 through the ground substance. Megascleres : — (/. ) Oxea 

 of the nuiin skeleton reaching a size of j2oo x ^u ]i ; (ii.) 

 styli (t)id asymmetrical oxea of the dermal brushes vary- 

 ing in length from less than 200 to about '-00 j(, witli 



spicules of the fibres are substrongyla) there are in addition scattered 

 small oxea. If in SvirasifDna ariiSfita the flbre-formin? strongyla dis- 

 appeared, the species would, without doubt, owing- to the mode of dis- 

 tribution of its smaller oxea, be classed as a GeiliiiK. 



1 Sollas— "Challenger" Tetraxonida, 1885, p. 432, pi. xliii., figs. 1-9. 



2 Thiele— Studien uber pazifisihe spongien, Zoologica, Heft 24, 1893, p. £6. 



