414 



REVISION OF THE MONAXONID SPONGES, 111. 



are very few tylota and moderately abundant chelae and sigmata, 

 the last-mentioned predominating. The microscleres are most 

 numerous surrounding the canals. The dermal skeleton appears to 

 be developed interruptedly, but this may be in consequence of the 



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11 



n 



u 



r\ 



w 



Fig. 16. — Lissodendoryx jacksoniajia. a, Principal styli. 

 a'jStrongylifoim modifications of principal spicules. 

 6, Auxiliary tylota. c.IsochelaB arcuatae. rf,Sigmata. 



abrasion of portions of the original surface; here and there, in 

 patches, closely-arranged short strands of tylota occur, disposed 

 vertically to the surface; while in the relatively broad intervals 

 between these gToups of strands the main skeleton extends almost 



