286 DISCOVERY REPORTS 



Diagnostic characters. The male of this species is a Httle broader in proportion to 

 its length than is the female, the largest male in the Challenger collection measuring 

 24-5 mm. in length and 25 mm. in breadth, and the largest female 27-5 mm. in length 

 and 26 mm. in breath. 



The head is broadest anteriorly and in this point differs from that of S. schythei, 

 Liitken, and S. poIaris, Richardson, two closely allied species, in both of which it is 

 broadest at about the level of the eyes. The flagellar joints (7-16, in one specimen) of the 

 antenna of both sexes are furnished with a series of short recurved hooks which corre- 

 spond with the "lamellar-like" structures of S. schythei. 



The body is less flattened than in the two allied species ; the coxal plates are smaller, 

 and those of the first four free somites are separated from them by sutures. I noticed 

 that in this species the positions of the sutures on the tergum of the fifth free somite, 

 which have disappeared, are indicated by shallow grooves. The coxal plates of the seventh 

 somite are produced backwards to a level about the middle of the terminal segment ; the 

 pleural plates of both the second and third abdominal segments are short, and do not 

 extend far beyond the anterior margin of the terminal segment ; those of the third are 

 slightly longer than those of the second segment. 



The ischium, merus and carpus of the third appendage in the male are furnished with 

 abundant plumose hairs arranged in two rows : these are absent from the corresponding 

 joints of this appendage in the two allied species. The terminal segment is more tri- 

 angular than in the other two species, and it bears on its dorsal surface a median 

 longitudinal keel on either side of which is a lateral one. A strong median spine is 

 situated in an anterior position, and running parallel to the anterior margin is a trans- 

 verse carina of which only traces exist in S. schythei; the transverse ridge of the latter 

 is absent in S. paradoxa. 



Distribution. Off the Falkland Islands, and adjacent shores of Patagonia. 



5. Serolis schythei, Liitken (Figs. 2b,c, ^a,b; Plate XIV, fig. i). 



S. schytliei, Lutken, 1858, p. 98, pi. i, figs. 12, 13; Grube, 1875, p. 220, pi. vi, fig. i ; Beddard, 18846, 

 p. 40, pi. ii, figs. 5-13; Tattersall, i92i,p.227; Giambiagi, 1925, pp. 1 1-12, pi. ii, fig. 3 ; Nordenstam, 

 1933. PP- 55-7. text-figs. 

 Occurrence. St. 51 : East Falkland Island, 115 m.; 19 (JcJ, 45 ?? (b.), and a number of immature specimens. 

 St. 223 : Cape Horn, 63 m. ; 6 ?? (b.), 4 immature. St. WS 72 : 51° 07' S, 57° 34' W, 79 m. ; 2 .^cJ. St. WS 73 : 

 51° 01' S, 58° 53' W, 121-130 m.; 5 <?<?, 4?? (b.), 2 immature. St. WS 75: 51° 01' 30" S, 60° 31' W, 72 m.; 

 2cJ<?, i$(b.), I immature. St WS76: 5i°oo'S, 62° 02' 30" W, 207-205 m.; a number of immature. 

 St. WS78: 5i°oi'S, 68° 04' 30" W, 91-95 m.; 3 immature. St. WS79: 5i°oi'3o"S, 64° 59' 30" W, 

 132 m.; I ?(b.), a number of immature. St.WSSo: 50° 57' S, 63°37'3o" W, 152-157 m.; 2cJo, 4?? (b-). 

 a number of immature. St. WS 83 : 14 miles S 64° W of George Island, East Falkland Island, 137-129 m.; 

 I immature. St. WS 90: 13 miles N 83° E of Cape Virgins Light, Argentine Republic, 82-81 m.; 3 ,5,^, 

 3?? (b.), and a number of immature. St. WS 210: 50" 17' S, 60° 06' W, 161 m.; i o, i $ (b.), i immature. 

 St. WS211: 50° 17' S, 6o°o6'W, 174 m.; I immature. St. WS214: 48° 25' S, 60° 40' W, 208- 

 219 m.; 1$ (non-b.), I? (b.), a number of immature. St. WS215: 47° 37' S, 60° 50' W, 219-146 m.; 

 5 immature. St. WS216: 47° 37' S, 60° 50' W, 219-133 m.; 2,5c?, 5??(b.), a number of immature. 

 St. WS 219: 47° 06' S, 62° 12' W, ii6-ii4m.; I4(J<J, 22$$ (b.), a number of immature. St. WS225: 

 50° 20' S, 62° 30' W, 162-161 m.; 2 immature. St. WS 226: 49°2o' S, 62° 30' W, i44-i52m.; i immature. 



