228 THE VOYAGE OF H.M.S. CHALLENGER. 



Ophiothrix comata, Mull. & Tr., Syst. Ast., p. 112, 1842; Lym., Bull. Mus. Comp. 

 Zool., vol. iii., part 10, p. 233. 

 Locality unknown. 



Ophiothrix capensis, Ltk., Addit. ad Hist., part 3, pp. 59, 100, 1869. 

 Cape of Good Hope. 



Ophiothrix viridialba, V. Mart., Monatsb. Konig. Akad. Berlin, p. 347, 1867. 

 China Sea ; 40 fathoms. 



Ophiothrix plana, Lym., Bull. Mus. Comp. Zool., vol. iii., part 10, p. 238, pi. iv. figs. 

 1-8, 1874. 



Philippines ; Macassar ; littoral. 



Ophiogymna. 



Ophiogymna, Ljn., Oni nigra nya arter, Of. Kong. Akad., 1866. 



Disk covered with a thick skin which hides all the radial shields except their outer 

 ends, and has embedded in it loose, ill-defined scales. Numerous crowded tooth papillae, 

 forming a vertical oval. Teeth. No mouth papillae. Spines numerous (five to ten) 

 (often three times as long as the joints), flattened, more or less glassy, thorny, having a 

 central shaft with slender side spurs from it. A small spinedike tentacle scale. The 

 base of the jaw pierced with a hole, from a want of perfect union between the two pieces 

 of the mouth frames. Interbrachial spaces swelled out like lobes. Two genital openings 

 beginning outside the mouth shields. Outer arm joints with hooks. 



In internal structure the genus does not materially vary from Ophiothrix. 



Ophiogymna elcgans, Ljn., Om nagra nya arter, Of. Kong. Akad., p. 163, 1866 ; 

 Oph. Viv. Of. Kong. Akad., p. 333, 1866 ; Ltk., Addit. ad Hist., part 3, p. 60, 1869. 



Station 203.— October 31, 1874 ; lat. 11° 7' N., long. 123° 7' E. ; 12 to 20 fathoms ; 

 mud. 



Ophiocnemis. 

 Ophiocnemis, Mull. & Tr., Syst. Ast., 1842. 



Disk covered by very large naked radial shields, and minute plates bearing numerous 

 grains. On the interbrachial spaces below, a fine scaling. Numerous crowded tooth 

 papillae forming a vertical oval. Teeth. No mouth papillae. Arm spines numerous, 

 rounded, microscopically fluted, not translucent, a little hollow in the centre. The base 



