OPHIUROIDEA 171 



appear that it breeds only once and then dies. Occurs on muddy 

 bottom like glacialis. 



In British seas this species has been found in the warm area 

 of the- Faroe Channel (" Porcupine "), and of! 8.W. Ireland 

 (■' Helga "), in 115-1380 m. A statement of its occurrence in the 

 cold area of the Faroe Channel (Hoyle) may perhaps rest on a 

 misidentification {0. glacialis ?). The species is elsewhere known 

 from Hardanger fjord on the coast of Norway to the White Sea, 

 and from the Bay of Biscay (" Talisman "). Also known from 

 Greenland, while the record of its occurrence in the West Indies 

 rests on a misidentification. Bathy metrical distribution ca. 75- 

 1380 m. 



3. Ophiophrixus H. L. Clark. 



Disk with scattered spines, attached to small plates in the 

 skin, which does not contain any glassy scales. Radial shields 

 fairly well developed, carrying a comb of spines. Tooth papillae 

 present. 



One species known from the British (and European) seas. 



1. Ophiophrixus spinosus (Storm). (Figs. 96, 97.) 



(Syn. Ophiohyrsa hystricis (Lyman) ; Ophioscolex spinosus 

 Storm ; Ophiohyrsella spinosa (Storm).) 



Dorsal plates of arms fairly well developed, divided by 

 a longitudinal furrow. Ventral plates short and broad in the 

 proximal part, farther out longer, contiguous, with a notch in 

 the outer edge. No tentacle scale. Arm spines 4-5, rather long, 

 closely set with small thorns (seen only after removal of the skin). 

 Mouth shields about as long as broad, somewhat rhombic. Adoral 

 shields broad, joining inside the mouth shield. Mouth papillae 

 and tooth papillae rather long, spine-like. Reaches a size of nearly 

 30 mm. diameter of disk. Length of arms nearly ten times the 

 diameter of disk. Colour in life brick-red ; tube-feet yellow. 



This species, which has hitherto erroneously been named 

 Ophiohyrsa hystricis, is probably the largest of British Ophiuroids 

 (not counting Gorgonocep)halus). It has been found in the cold 

 area of the Faroe Channel (" Porcupine ") and on several places 

 of S.W. Ireland (" Flying Fox ", " Helga ") in depths of ca. 

 400-1250 m. ; also recorded from the Lousy Bank. It is elsewhere 

 knowTi only from the Trondhjemfjord and from between Madeira 

 and the African coast ('' Talisman "). The occurrence in the 



