32 DISCOVERY REPORTS 



St. WS788. 13. xii. 31. 45° 05' S, 65°oo'W. Commercial otter trawl, 82-88 m. : 2 male specimens, 

 370, 375 mm. (width of disc 230, 235 mm.). 



St. WS 797. 20. xii. 31. 47 47' 43" S, 64 07' 30" W. Commercial otter trawl, 111-114111.: 

 1 female specimen, 78 mm. (width of disc 43 mm.). Seine net attached to back of trawl, 11 5-1 11 m.: 



1 male specimen, 85 mm. (width of disc 53 mm.). 



St. WS 798. 21. xii. 31. 47 32' S, 65 02' W. Net (4 mm. mesh) attached to back of trawl, 

 49-66 m.: 1 male specimen, 76 mm. (width of disc 42 mm.). 



St. WS810. 9.1.32. 49 17' S, 67° 08' W. Commercial otter trawl, 95-96 m.: 10 male specimens, 

 155-195 mm. (width of disc 95-125 mm.), 7 females, 170-210 mm. (width of disc 103-125 mm.). 



St. WS 817. 14. i. 32. 52 23' S, 64 19' W. Commercial otter trawl, 202-238 m.: 1 female 

 specimen, 390 mm. (width of disc 255 mm.). 



Disc broader than long, its width f to a little more than f of the total length ; nearly 

 circular in young; anterior margins scarcely undulated, not emarginate in females or 

 immature males, notched in mature males; outer angles broadly rounded. Vent nearer 

 to tip of snout than to end of tail. Snout not produced, but often with a small barbel-like 

 process, sometimes borne on a small fleshy projection; this process may be absent 

 altogether, or may persist even in the adult ; length of snout \% to about 6 in width of 

 disc ; interorbital width equal to or rather greater than longitudinal diameter of eye ; 

 length of eye + spiracle about twice in that of snout. Internasal width 2-i to nearly 3 in 

 praeoral length of snout. Mouth a little undulated in females and immature males, 

 but with a marked concavity in the upper jaw in mature males ; in females and immature 

 males the teeth are nearly flat, in mature males the median teeth have pointed crowns, 

 but laterally the points are directed towards the corners of the mouth, and the extreme 

 lateral teeth are more or less flat ; in some specimens the crowns are so much worn that 

 all the teeth appear flat; 28 to 40 rows of teeth in the upper jaw. Upper surface of 

 disc in the young of both sexes covered with minute spinules and rough to the touch ; 

 the spinules are most numerous on the anterior parts of the pectoral fins, on the snout, 

 round the eyes, and along the back ; there are no enlarged spines on the disc, but an 

 irregular median series of spines of moderate size on the tail, which commences behind 

 the pelvics ; upper surface of tail covered with small spinules, which are rather larger 

 than those on the disc. In larger specimens there are generally 1 to 4 median spines on 

 the nuchal region ; 1 to 3 praeocular and 1 to 4 postocular spines, the two series some- 

 times united to form a row of 6 or 7 spines above each orbit ; no scapular spines ; small 

 spines on anterior parts of pectorals, on snout, round the eyes, and on the back, but 

 the disc is otherwise smooth; tail with 3 rather irregular rows of larger spines, the 



2 outer series in some individuals extending anteriorly on to the disc as far as the 

 suprascapulary region. Mature males with 2 to 4 series of alar spines. Lower surface 

 quite smooth. Dorsal fins close together, generally more or less united, separated from 

 or continuous with the caudal fin (when this is present). Brownish or greyish, with or 

 without a number of small scattered dark spots ; sometimes, in addition, some small, 

 rounded, white spots of varying size, which may be more or less symmetrically arranged ; 

 tail in young often with 2 broad pale cross-bars on its upper surface ; lower surface of 

 disc and tail usually uniformly yellow or white. 



