54 THE VOYAGE OF H.M.S. CHALLENGER. 



Royal Sound, Kerguelen Islands ; 25 to 28 fathoms. Balfour Bay, Kerguelen 

 Islands; 20 to 60 fathoms. Off Christmas Harbour, Kerguelen Islands; 120 fathoms. 



Ophioglypilia ambigua, Lym. (PI. VIII. figs. 4, 5). 



Ophioglypha ambigua, Lym., Bull Mus. Comp. ZooL, vol. v., pt. 7, p. 79, pL ii. figs. 47, 48, 1878. 



Four short, blunt, peg-like arm spines, three together, low down, and one higher up. 

 Papilla? of arm comb short, close set, and squarish. Disk scales of moderate size, thick 

 and swollen. Very small, narrow side mouth shields. 



(Type specimen from Royal Sound, Kerguelen.) Diameter of disk, 13*5 mm. 

 Width of the arm close to disk 2 "5 mm. Mouth papilla? short, blunt, tooth -like, 

 and close set, five on each side, similar to and continuous with the tentacle 

 scales of the mouth tentacles, with a larger, longer, and pointed one at angle of jaw. 

 Mouth shield pentagonal, with outer edge rounded, lateral sides notched, and a blunt 

 angle inward ; length to breadth 3 : 2. Side mouth shields short, just meeting 

 within and slightly wider at their outer end. First under arm plate large, rudely 

 diamond - shaped, with outer and inner angles rounded ; the next two or three 

 plates four sided, wider without than within, with outer side curved and re-entering 

 curves on lateral sides ; further out they become pentagonal, much broader than long, 

 with an angle inward. Side arm plates short and thick, not meeting below till some 

 distance from the disk ; widely separated above by upper arm plates, much broader than 

 long, arched, wider without than within, outer edge curved, inner edge re-enteringly 

 curved. Disk thick and angular, covered with thick, closely soldered, irregularly shaped 

 plates, among which the primaries may be distinguished, but not very clearly. Radial 

 shields small, irregularly triangular, with angles rounded, widely separated by one large 

 and two or three small scales ; length to breadth 2 : l - 5. Genital plates short, beginning 

 opposite fourth under arm plate and widening rapidly outward ; along the free edge is a 

 row of fine, short, square, close-set papilla?, extending as an unbroken line upward to form 

 the arm comb. Four short, blunt, and tooth-like arm spines, three in a cluster, close to 

 edge of tentacle pores, and one a little separated above ; farther out the four make a 

 continuous group. Tentacle pores large ; those of the mouth tentacles have five short, 

 rounded scales on the interbrachial side and four on the other ; the next pair, six on one 

 side and five on the other ; thence they dimmish till some distance beyond the disk, 

 where there is but one tentacle scale, simdar to and continuous with the arm spines. 

 Colour in alcohol, light grey. 



It is near Ophioglypha brevispina, from which it differs in having one more arm 

 spine, and an arm comb of close-set, square papilla?, instead of pointed ones. 



Royal Sound, Kerguelen Islands ; 25 to 28 fathoms. Off Christmas Harbour, 

 Kerguelen Islands ; 120 fathoms. 



