112 OPHIDROIDEA. 



long. Under arm-plates quite small, wider than long, with a well- 

 marked curve to the outer edge. A single tentacle-scale on joints 

 beyond the disk. Lateral arm-plates meet below, bear about five 

 spines, which are not as long as the plates except near the disk. 

 Upper arm-plates oblong near disk, where they are wider than long, 

 then quadrate, and then longer than square. 



R=9; r=2. 



Colour in spirit white ; alive reddish yellow, occasionally pale 

 sandy (Hodge). 



Of this species Hodge remarks that it exhibits excessively lively 

 movements and has wonderfully pliable rays. 



Distribution. East and west coasts of North Atlantic, and Medi- 

 terranean. 10-192 fms. 



7. Ophiura aurantiaca. 



Ophioglypha aurantiaca, Verrill, Amer. Journ. Set. xxiii. (1882) 

 p. 141 ; Lyman, Proc. E. Soc. Edinb. xi. (1882) p 707 ; id. Bull. 

 Mus. C. Z. x. (1883) p. 240; Hoyle, Proc. R. Soc. Edinb. xii. 

 (1884) p. 717. 



Ophiopleura aurantiaca, Verrill, op. cit. p. 248. 



Of this species, which I have not seen, some specimens with 

 broken arms were dredged in the warm area of the Faeroe Channel 

 at 516-570 fms. 



Mr. Lyman gives as its " special marks ": — 



"Disk covered by a smooth skin, through which the scales of the 

 upper surface are scarcely to be made out, while those of the lower 

 surface are more distinct. Three wide flattened arm-spines, the 

 upper one longer than an arm-joint, the others not so long. No 

 comb above the base of the arm." 



Distribution. Both sides of the North Atlantic, 466-570 fms. 



Prof. Verrill's full description is as follows : — 



" Disk large, swollen, nearly round, with small notches, destitute 

 of papillae, at the bases of the five arms ; dorsal surface covered by 

 very numerous small, imbricated scales, partially concealed by a 

 soft skin ; in the central area they are crowdedly arranged around 

 one or more larger central plates ; the marginal interradial scales 

 are larger and thicker, with a median radial row of two or three 

 still larger ones ; ventral scales convex, unequal, imbricated. Radial 

 shields convex, irregularly subtriangular, with rounded corners and 

 outer edge, as broad as long, separated by a group of three or more 

 imbricated disk-scales. Mouth-shields shorter than broad, with an 

 obtuse inner angle, a nearly straight outer edge, and short, notched, 

 lateral edges. Side mouth-shields long and rather broad oblong, 

 meeting within. Mouth-papillae very small and irregular, 7 to 9 

 on each side of each angle, those next to the teeth longer and 

 pointed. Teeth slender, acute. Innermost tentacle-pores large, 

 bordered on the outside by about six small flat scales, on the inner 

 by about four. Arms somewhat rigid, rather short and stout, not 



