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



breadth 3'5:2"5. Side mouth shields narrow, curved, pointed within, where they 

 broadly meet. The first under arm plate broad triangular, with outer edge curved, and 

 a blunt angle within ; the next three long axe shape, with outer edge, which is wider 

 than inner, slightly curved, and lateral sides re-enteringly curved ; beyond the disk they 

 are similar, but present an angle inward. Side arm plates minutely tuberculous, broad, 

 and swollen meeting below at some distance beyond the disk ; separated above by upper 

 arm plates, of which the first is much wider than long ; the second wide semicircular, 

 with outer edge curved ; the third narrower, with outer edge curved, and wider than 

 the inner ; the rest rounded diamond shape, with the inner angle longer than the outer. 

 Disk thick, covered with thin flat plates ; in the centre is a large round primary plate, 

 smTOunded by five smaller, separated by two or three rows of fine scales ; in the 

 interbrachial spaces are three large plates in a line, of which the outer is marginal and 

 has usually a round plate on either side. Eadial shields irregular blunt pear-seed shape, 

 touching without, diverging inward, where they are separated by a wedge of three or 

 four small rounded scales. Genital scales narrow within, growing much wider with- 

 out ; bearing on their free edge a close row of squarish papillae, which become spini- 

 form where they pass upward to form the arm comb. Six minute blunt arm spines 

 equally spaced along the side arm plate. Four or five small blunt tentacle scales on 

 each side of pores within the disk ; beyond the disk they soon diminish to two standing 

 inside of pore. Colour in alcohol, light grey. 



Station 237.— June 17, 1875; lat. 34° 37' N., long. 140° 32' E. ; 1875 fathoms; 

 mud. 



Ophioglyplia variabilis, Lym. (PI. VI. figs. 10-12). 



OpMoglypha varmhilis, Lym., Bull. Mus. ComiJ. Zool., vol. v., part 7, p. 85, pi. iii. figs. 70, 78, 

 79, 1878 ; Bull. Mus. Comp. Zool, vol. v., part 9, p. 217. 



Four or five minute arm spines. Under arm plates longer than Inroad. Radial 

 shields separated at inner ends by a single scale. Disk high. Basal under arm plates 

 about as long as broad. Arms high and rounded. 



(Type specimen from Station 195.) Diameter of disk 11 "5 mm. Length of arm about 

 40 mm. Width of arm close to disk 2'7 mm. Mouth papillae six on each side, of which 

 three are square and three pointed, and one larger and diamond shaped at apex of jaw ; 

 they are all low and somewhat irregular. Mouth shield blunt pear-seed shape with an 

 angle within, or of a much rounded pentagonal form with an angle within and a curve 

 without ; length to breadth 3*3 : 27. Side mouth shields narrow, meeting within and 

 there forming a sharp angle. First under arm plate triangular, outer edge curved, inner 

 angle blunt ; the next three plates are long axe-shaped, with outer edge, which is wider 

 than inner, curved, and re-entering curves on the lateral sides ; those beyond are sep»arated 



