134 



"ENDEAVOUE" SCIENTIFIC RESULTS. 



an approximately parallel arrangement. (The general struc- 

 ture and arrangement of the skeleton were examined micro- 

 scopically only in the branch-like processes ; the following 

 description is drawn from a rather thick median longitudinal 

 section of one of such preserved in alcohol. Owing to the 

 great development of spicules and their disposition, the pre- 

 paration of a transverse section would be wholly impossible 

 without desilicification. The structure of the main body of 

 the sponge is apparently not essentially different from that 

 described for the processes). 



Fig. 27 — Patacordyla lignea. Vertical section, sliow- 

 ing the arrangemeut of the skeleton in the cortical 

 and subcortical region. 



Superficially, there is a fairh- well-defined layer, about 150 ji 

 in thickness, densely packed with perpendicular microxea 

 which appear to project about half their length beyond the 

 surface. In addition, the surface is provided with brushes of 

 fusiform styli and oxea, of much shorter length than the 

 spicules composing the main skeleton. The components of a 

 single bundle diverge from a point close beneath the cortex. 

 With the exception of a sub-cortical zone about two or three 

 millimetres wide the whole of the interior of the branch-like 

 process is occupied by an almost solid core of longitudinally- 



