﻿OPIIIOCTEN. 53 



OPHIOCTEN LiJTKEN. 



Disk thick and circular, without notches where the arms join it ; 

 partly covered by primary plates and radial shields, between Avhich are 

 fine, close set grains, or small scales, covering the squamous coat ; on 

 the interbrachial spaces below, a simple squamous coat, without any 

 covering of grains. A row of papilla), passing along the genital slits, 

 and upwards, along the margin of the disk, over the arm. Some of the 

 basal upper arm-plates bearing papillas along their outer edge. Disk 

 cut away at the base of the arm, so as to form a little arch over one or 

 two upper arm-plates which are within the margin of the disk. Side 

 ann-plates meeting below, but not above. Teeth. Mouth-papilla3. No 

 tooth-papilljB. Arm-spines arranged along the outer edge of the side 

 arm-plates. Two genital slits, beginning at the sides of the mouth- 

 shields. 



Ophiocten Kroyeri Lutken. 



Ophiocten Kroyeri Lutken. Vidensk. Meddelelser. Nov., 1854. 

 Ophiura sericea ? Forbes. Sutherland's Journal of a Journey. 

 Ophiocten Kroi/en LiJTKEN'. Addit. ad Hist. Oph., p. 52. 



Sjyecial Harks. — Arms three to four times the length of the diam- 

 eter of the disk ; two upper arm-spines much the longest ; papilla3 of 

 arm-comb continuous ; first, second, and third upper arm-plates bearing 

 papillee ; sometimes, also, the fourth. 



Description of a Sjjeciinen. — Diameter of disk, 8.7°"°' ; from outer 

 side of mouth-shield to outer corner of opposite mouth-slit, 4.2'°"' ; width 

 of arm without spines, 1.9""°-; length of arm, 31™- ; distance from outer 

 side of mouth-shield to inner points of mouth-papillaj, to that between 

 outer corners of mouth-slits, 2.5 : 1.9. Mouth-papillEe, seven or eight to 

 each angle of the mouth ; close set, and making an even row ; outer 

 one very much the widest, flat, straight, angular ; the next two (or 

 three) similar in shape, but much narrower, and more rounded or 

 pointed, innermost one lying directly below teeth, and similar to them, 

 being shaped like a very short, thick, blunt spear-head. Teeth six, set 

 close one above the other, longer than broad, flat, pretty thick, with a 

 blunt point inward ; uppermost one narrower than those below. Mouth- 

 shields longer than broad, bounded without by a long, ovoid curve, and 

 -ndthin presenting an angle ; length to breadth, 1.7 : 1.3. Side mouth- 

 shields meeting within, extremely narrow, but swelling at their outer 

 end into a little knob. Under arm-plates very short, by I'eason of the 



