>rONOGiL\PH OF JAPANESE OPHIUROIDEA. 



297 



Ophioxonella longispina (Claiik). 



OpJiiokona longispina : Clakk, Bull. Mns. Comp. Zool., LT, 1908, p. 



290; Clark, Bull. U. S. Nat. Mus., LXXY, 1911, p. 33. 



Numerous specimens ; Suruga Gulf. Numerous specimens ; 



Sagami Sea. 



Off Heda ; 337 fathoms (Clark). Suruga Gulf ; 45-124 fathoms 



(Clark). Uraga Channel ; 58 fathoms (Clark). Off eastern Japan ; 



101 fathoms (Clark). 



The supplementary tentacle scales are very well developed. 



In the basal arm 



joints, there are one 



or two of them on 



the adradial border 



of each pore, beside 



one large, oval or- 

 dinary scale on the 



abradial border. So 



that, the tentacle 



scales of this species, 

 as well as of Ophio- 

 ■lonella alba (Lütken 

 & Mortensen), re- 

 mind us of those of 

 Ophiodoris and of 

 certain species of 

 Ophiochiton. The 

 dorsal and ventral 

 arm plates are re- 

 latively wider than in many other species of this genus. The 



Fig. 80. Ophiozonella longispina. x3.3. a. From fibove. 

 5. From below, c. Side view of three arm joints near 

 disk. 



