﻿SPONGES.-HALLMANN. 



133 



niaxiniiini diaDictcr of iS ;/. .1/ 

 croxea, 100 to 770 ;< /?/ leno;th by n 

 (/('.) cuu pinasters, 4 to 5 /( /(>»i,'. 



The single specimen is a moderately 

 large, massive, sessile sponge, of great 

 density and solidity, with a rounded 

 cuboidal or sub-globose body which 

 measures about 120 mm. in each of its 

 three principal directions. From the 

 marginal region of the somewhat flat- 

 tened upper surface of the main bod^ 

 there are given off, at sub-equal dis- 

 tances, three stout branch-like pro- 

 cesses, 100 to 150 mm. in length. One 

 of these is cylindrical, the others are 

 club-shaped and are polytomousl\- 

 di\ ided at their extremities into in- 

 cipient branches. The specimen, which 

 has been longitudinally bisected, is, with 

 the exception of one of its processes, 

 preserved in a dry state. The contrac- 

 tion resulting from drying has caused 

 the surface to split in places, giving rise 

 to a number of shallow gaping- fissures, 

 such as are occasioned under similar 

 circumstances in many Axinellids. The 

 surface of the dried portion somewhat 

 resembles short-piled velvet, both in 

 appearance and to the touch ; that ol 

 the spirit piece has a harsher feeling. 

 The colour of the former is ^■ellowish- 

 white, both externally and internally ; 

 the latter is similarly tinted, except 

 superficial!}-, where to a depth of about 

 one-third of a millimetre, it exhibits an 

 intense purple colouration which, how- 

 ever, is almost certainly a stain derived 

 from crinoids originally preserved in the 

 same liquid. The texture, as revealed 

 by the cut surface resulting from th( 

 bisection of the specimen, bears a close 

 resemblance to that of some coarse and 

 exceedingly short-grained hardwood. 

 1 he densely packed spicules are visible 

 to the naked eye, and throughout the 

 entire central mass of the sponge have 



icrosclcres : — (/. ) Mi- 

 bout 4 }i in diameter ; 



l/b 



Fig. 26 - /'. /io),ea. 

 a Oxea (showing the 

 spicule's extremities, and 

 its diameter relatively 

 to that of tlie other 

 spicules). b Styli (of 

 the dermal brushes), c 

 Microxea. 



