OPHIUROIDEA 249 



In British seas this species has been found at 50° 03' N., 

 12° 33' W., 147 m. (" Hirondelle "), and 59° 03' N., 4° 08' W., 



Fig. 135. — Ophiocten scutatimi ; part of oral side. x 10. 

 (From Koehler, Monaco, xii.) 



88 m. (" Princesse Alice "). Elsewhere known from the Bay 

 of Biscay, 160 m., and off Newfoundland, 155 m. (" Hiron- 

 delle "). 



3. Ophiopleura Danielssen and Koren. 

 (Syn. Lutkenia Duncan, non Brock.) 



Scales of disk very small, concealed by the skin. Edge of disk 

 not sharp ; a more or less conspicuous notch in the disk above 

 the base of arms, but no arm combs. Otherwise as Ophiura, 



The two species known of this genus are both found in the 

 British seas. 



Key to the species of Ophiopleura Icnoivn from the British seas. 



Ventral plates much broader than long, all separated. Genital 

 slits short, not reaching to the edge of disk 



1. O. borealis Dan. and Koren 

 Ventral plates scarcely broader than long, the proximal ones con- 

 tiguous. Genital slits long, reaching to edge of disk 



2. O. aurantiaca (Verrill) 



1. Ophiopleura borealis Dan. and Koren. (Fig. 136.) 



(Sjrn. Lutkenia arctica Duncan ; Ophiopleura arctica (Duncan).) 



Scales of disk, as seen on dried specimens, very small, 

 irregular ; primary plates very small, still fairly distinct. Radial 

 shields widely separated, very small, oval, scarcely J the disk 

 radius, but they are seen to continue beneath the scales as more 

 or less distinct ridges nearly to the centre of the disk. Notch 



