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



Species of Ophiomaza not herein described. 



Ophiomaza obscura, Lym., Bull. Mus. Comp. Zool., vol. iii., part 10, p. 233. 



Ophiocnemis obscura, Ljn., Oph. Viv. Of. Kong. Akad. p. 333, 1866. 

 Singapore. 



Opliioiliela. 



Ophiothela, V1L, Trans. Conn. Acad., vol. i., 1867. 



Disk covered by very large naked radial shields'and a few irregular scales. Numerous 

 crowded tooth papillae forming an irregular vertical oval. Teeth. No mouth papillae. 

 Arm spines thorny, clubbed and very short, borne on pad-like side arm plates which 

 stand out free from the arm. Upper arm plates broken in irregular pieces, or represented 

 by several wart-like swellings. The base of the jaw is pierced with a vertical hole. 

 Interbrachial spaces somewhat swollen. Two large genital openings beginning outside 

 the mouth shields. 



The skeleton is like that of Ophiothrix. 



Table of Species of Ophiothela. 



Radial shields large. Interbrachial spaces set with short, thick spines. Six arms | . , . . 



, ..... } Ophiothela mvrabihs. 



whose upper surface bears grams or minute spines, . . . ■ ) 



Radial shields large, and interbrachial spaces very narrow, and smooth or set with a 

 few grains. Six arms, whose upper surface is sparsely granulated, 



> Ophiothela dance. 



Disk above covered wholly by large smooth radial shields. Five arms which have a ) 



..... ,. ( Ophiothela hqris. 



few warts or grains on their upper surface, . . . . . ) 



Disk covered by a thick skin, set with scattered grains which obscure the large radial ) 



,.,.„. , „ , , j ii • f Ophiothela isiaicola. 



shields. Six arms, whose upper surface bears larger and smaller grains, . . ) r 



Disk with radial shields of moderate size, so that there is a free central space which \ 



with the shields bears thorny grains ; and these are continued along the tops of \ Ophiothela dividua. 

 the six arms, . . . . . . . . • ) 



Species of Ophiothela not herein described. 



Ophiothela mirabilis, VT1., Trans. Conn. Acad., vol. i. p. 268, 1867. 

 Panama Bay. 



Ophiothela dance, Vll., Proc. Bost. Soc. Nat. Hist., vol. xii. p. 391, 1869. 

 Fiji Islands. 



Ophiothela tigris, Lym., 111. Cat. Mus. Comp. Zool., No. vi. p. 10, pi. i. figs. 

 10-12, 1871. 



U.S. Pacific Exp. Expedition? 



