MONOGEAPH OF JAPANESE OPHIUKOIDEA. 



301 



Senekeuberg. Naturf. Gesell., XXI, 1899, p. 544 ; Pfeffer, ibid., XXV, 1900, 

 p. 83; Kœhlee, Exp. Siboga, XLI, Pt. 2, 1905, p. 17; Clark, Bull. Mus. 

 Comp. Zool., LI, 1908, p. 289. 



One specimen ; Okinawa. 



Indo-Pacific. Okinawa is 

 probably the northern limit of 

 this species. 



The radial shields are larger 

 and the space between each 

 radial pair is narrower than 

 in Lütken's figure. The colour 

 is quite similar to Lütken's. 

 The arm spines are only five 

 or rarely six in number, so 

 that they are fewer than in 

 MüLLEE & Tkoschel's type. 



Fig. 82. Ophiolepis annulosa. x3. a. 

 From above, h. Side view of three iirm 

 joints neur disk. 



Key to Japanese species of Oplüoplociis, 



A — Disk scales more or less couvex, so that the surface of the disk 

 is rather rough ; genital slits very short, pore-like ; the halves of 

 each dorsal arm plate proper separated from each other by six 



larger and a few smaller supplementary plates imhricahts. 



AA — Disk scales flat, so that the surface of the disk is very smooth ; 

 genital slits rather long, slit-like; the halves of each dorsal arm 

 plate proper separated from each other by eight to ten larger and 

 several smaller supplementary plates japonicus. 



Oxtliioplocus imhricatus (Müller k Troschel). 

 Ophiolepis imhricata : Müller & Troschel, Sys. Ast., 1842, p. 93 ; 

 LÜTKEN, Addit. ad Hist. Oph,, n, 1859, p. 160. 



OpMoploczis iessellatus : Lyman, Proc. Boston Soc. Nat. Hist., VIII, 

 1861, p. 76^>. 



