J 48 THE DEPTHS OF THE SEA. [CHAP. 



arranged vertically, and this peculiar tissue forms a 

 complete sheath surrounding a pulpy mass of gra 

 nular horny and sarcodic matter which fills the in 

 terior. In this inner spongy substance sheaves of 

 similarly-shaped spicules are likewise arranged ver 

 tically, but much more loosely ; and the projecting- 

 scales forming the head of Thecophora ibla are formed 

 by the projecting ends of such sheaves. Among- 

 echinoderms, Ophiacantha spinulosa was one of the 





FIG. 24. rAfcoptoro iWo, WYVILLR THOMSON. Twice the natural size. (No. 76. ) 



prevailing forms, and we were greatly struck witl: 

 the brilliancy of its phosphorescence. Some GJ 

 these hauls were taken late in the evening, and the 

 tangles were sprinkled over with stars of the most 

 brilliant uranium green ; little stars, for the phos 

 phorescent light was much more vivid in the youngei 

 and smaller individuals. The light was not constant 

 nor continuous all over the star, but sometimes il 

 struck out a line of fire all round the disk, flashing 



