REPORT ON THE OPHIUROIDEA. 161 



Ijoue, in a way that brings to mind Ophiothrix. Opliionereis is found iu sliallow tropical 

 waters all over the world, and yet is remarkable for its few species and their close 

 resemblance. 



See Plate XL. figs. 13-15. 



Table of Species of Opliionereis. 



' Disk scales very fine and thin, 13-15 to a millimetre in centre of upper disk, I 



and in interbrachial spaces below, / OpJtiowreh d„hia. 



Extremely like OpMonereis duhia save in colour (a purple patch outside \ 



mouth shields, and in general light yellowish). In young perhaps disk > OpMonereis reticulata. 

 I scales are coarser, . . . . . . . j 



Very like Ophionerei^ reticulata, except middle arm sj^ine usually longer ; ) 



disk scales of young coarser. Colour olive, with purple arm bands, . | OpMonereis anmdata. 



Scaling coarsest of all, with numerous larger scales. At centre of disk about 1 , . 



9 in the length of a millimetre. Young wth scales decidedly thickened, ^ P'''''^ - ^ V 





a g [ Scaling about the same as in OpMonereis duhia, .... OpMonereis sehayeri. 



'^ &■ ( Scaling coarser than in the preceding species, with more large scales, . OpMonereis albomacidata. 



Opliionereis duhia, Lym., 111. Cat. Mus. Comp. Zool., No. i. p. 149, 1865 ; 

 V. Martens, Wieg. Archiv, vol. xxxvi. p. 246. 



OpMure, Savigny, Descr. de I'Egypte Echin., pi. i. figs. S'-Sio, 1809-25. 



OpMolepis duhia, Miill. & Tr., Syst. Ast., p. 94. 



OpMonereis crassispina, Ljn., Oph. Viv. Of. Kong. Akad., p. 311, 1866. 



Professor P. M. Duncan^ writes this species Opliionereis duhia, Audouin. Here is 

 one more example of the troubles that come from placing authorities according to honour 

 or credit, instead of using them as parts of an exact and convenient system of registra- 

 tion. Anybody who is acquainted with the tradition of the Jardin des Plantes knows 

 that Audouin is not entitled to the " credit of discovery and exact I'cpresentation." 

 Savigny discovered the species and had it drawn. When, after long delay in the publi- 

 cation, Savigny broke down, Audouin was appointed to edit this part of the work. His 

 editing was such as only Carlyle could properly describe ! 



It is hardly needful to add that a student, seeing the name Opliionereis dubia, 

 Audouin, might well hunt for a week, only to find at last that Audouin never called it 

 by either of those names, did not describe it, and, in fact, knew nothing about it. 



Fiji Islands, same species ? Gomera, Canary Islands, same species ? Amboyna ; 

 100 fathoms. 



' Linn. See. Jour. Zool., vol. xiv. p. 4G4. 



