16 DISCOVERY REPORTS 



St. WS 218. 2. vi. 28. 45°45'S, 59 35' W. Commercial otter trawl, 311-247 m.: 1 female 

 specimen, 300 mm. (width of disc 230 mm.). 



St. WS 245. 18. vii. 28. 52 36' S, 63 40' W. Commercial otter trawl, 304-290 m. : 1 male 

 specimen, 430 mm. (width of disc 330 mm.). 



St. WS 783. 5. xii. 31. 50 08' S, 59° 50' W. Commercial otter trawl, 155-159 m.: 1 male 

 specimen, 200 mm. (width of disc 150 mm.). 



St. WS 794. 17. xii. 31. 46 12' 37" S, 6o° 59' 15" W. Commercial otter trawl, 123-126 m.: 

 1 female specimen, 260 mm. (width of disc 200 mm.). 



St. WS 795. 18. xii. 31. 46 14' S, 6o° 24' W. Commercial otter trawl, 1 57-1 61 m.: 1 male 

 specimen, 195 mm. (width of disc 145 mm.), 1 female, 210 mm. (width of disc 150 mm.). 



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

 specimen, 330 mm. (width of disc 260 mm.). 



St. WS 820. 18.1.32. 52 53' 15" S, 6i°5i'3o"W. Commercial otter trawl, 351-367 m.: 



1 female specimen, 225 mm. (width of disc 170 mm.). 



St.WS85i. 11.ii.32. 51 39' 30" S, 62° 01' 15" W. Commercial otter trawl, 221-197 m.: 2 male 

 specimens, 195, 200 mm. (width of disc 140, 145 mm.). 



Disc broader than long, its width about f of the total length ; anterior margins in 

 females and immature males more or less undulated but scarcely emarginate ; in mature 

 males these margins are more or less distinctly notched ; outer angles of disc obtusely 

 pointed. Vent nearer to end of tail than to tip of snout. Snout scarcely projecting, its 

 length a little more than \ (young) to about \ width of disc ; interorbital width about 

 equal to longitudinal diameter of eye; length of eye+spiracle 1^ times to about twice 

 in that of snout. Internasal width § praeoral length of snout. Mouth nearly straight; 

 teeth with pointed crowns, sometimes worn down so that the teeth appear flat; 28 to 

 34 rows in the upper jaw. Upper surface of disc with scattered spines, each sharply 

 pointed and usually with a stellate base; hinder parts of pectoral fins smooth; in adult 

 males and perhaps also in mature females these scattered spines are relatively smaller; 

 a single strong praeocular, and 2 postocular spines, of which the more posterior is the 

 larger ; a large median spine on the back in the suprascapulary region and a single nuchal 

 spine a little further forward ; 3 smaller scapular spines, of which the innermost is the 

 smallest; a series of 12 to 15 strong median spines extending from a point well in front 

 of the hinder angle of the pectoral fin to the first dorsal fin ; a row of much smaller 

 spines on either side of the median series and a narrow area of asperities along each 

 edge of the tail ; all the enlarged spines on the disc and tail ribbed ; mature males with 



2 or 3 series of alar spines. Lower surface quite smooth. Dorsal fins close to end of 

 tail, separated by a single (occasionally 2) spine. Brownish, with scattered and rather 

 indistinct darker spots and blotches; in one female specimen (Plate III) there is a pair 

 of yellowish-white blotches immediately in front of the eyes and one on either side in 

 the angle between the pectoral and pelvic fins ; lower surface uniformly yellow or white, 

 the tail sometimes stained with greyish. 



Hab. Argentina; Patagonian-Falklands region. 



This species is very closely related to the European R. radiata, Donovan, 1 but in 

 that species the tail is longer, the vent being nearer to the tip of the snout than to the 



1 R. scabrata, Carman, from the east coast of North America, will probably prove to be synonymous 

 with the European form. 



