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REVISION OF THE MONAXONID SPONGES, 11. 



Of the four specimens at hand, the largest measures 100mm. long, 

 by 70 mm. broad, and from 2 to 15 mm. in thickness; according 

 to the original description, the sponge may grow to a thickness 

 of 50 mm. 



The main skeleton is an irregularly renieroid, paucispieular reti- 

 culation, the pattern of which usually appears much confused 

 owing to the great number of scattered bundles of raphides: 

 spongin is present in minute quantity, though apparently only at 

 the angles of the meshes. In the most superficial region, loose 

 polyspicular strands of spicules occur, which run perpendicularly 

 to the surface and terminate in slightly projecting tufts coinciding 

 in position with the nodes of the dermal reticulation. The dermal 

 reticulation, for the most part, is triangular in pattern, and has 

 the sides of its meshes formed of from two to five roughly parallel 

 spicules. 



Fig. 10. — Gellhis raphidiophora. a, Oxea. 6, Sigmata. c, Longer raphides. 

 d, Shorter raphides. e, Microstrongyles. 



Spicules. — (a) Slightly curved oxea, very nearly cylindrical 



throughout the greater part of their length, and tapering gradually 



to sharp points. Size* : (i) 150 to 215 by 9-5/x; (n) 120 to 195 by 



^ 



* The two sets of measurements — which refer to the range in length of 

 the spicules, and to their maximum stoutness — are taken from the speci- 

 mens whose spicules are the most different in point of size; the former 

 measurements are those of the type-specimen. 



