RICHARDSON'S SKUA. 97 



underlying spots are small and indistinct. Axis, 2'25-2'5 

 inches; diam., 1-85-1-75. 



ii. RICHARDSON'S SKUA. STERCORARIUS CREPIDATUS. 



Larus crepidatus. Banks, in Cook's Voy. Hawksworth's ed. ii. 



P; 15 (I773)- 

 Lestris richardsoni, Swains. ; Macgill. Brit. B. v. p. 492 (1852) ; 



Lilford, Col. Fig. Brit. B. part xxxi. (1896). 

 Stercorarius crepidatus, Dresser, B. Eur. viii. p. 471, pis. 



611, 612, fig. 2 (1876); B. O. U. List Brit. B. p. 195 



(1883) ; Saunders, ed. Yarrell's Brit. B. iii. p. 674 (1884) ; 



id. Man. Brit. B. p. 675 (1889). 

 Stercorarius richardsoni, Seebohm, Hist. Brit. B. iii. p. 353 



(1885). 



(Plate CHI.} 



Adult Male (Pale Form). General colour above dark slaty- 

 brown, the wing-coverts like the back ; bastard-wing, primary- 

 coverts and primaries blackish, with yellowish-white shafts, 

 light ashy-brown on the inner web, with a little white 

 at the base of both webs ; tail slaty-brown, blacker towards 

 the end of the feathers, the two centre feathers much 

 elongated , crown of head darker slaty-brown, forming a cap, 

 with a line of white at the base of the forehead ; lores and 

 feathers under the eye slaty-brown, blacker in front of the 

 eye ; remainder of sides of face and sides of neck white, as 

 well as a collar round the hind neck, with a tinge of 

 straw-yellow; the hind neck and upper mantle light ashy- 

 brown, with white shaft-lines ; under surface of body white, 

 with a shade of ashy-brown on the fore-neck, darker and more 

 distinct on the sides of the breast and sides of body, and 

 again darker on the under tail-coverts, with white shafts and 

 bases to the latter feathers ; under wing-coverts and axillaries 

 lark slaty-brown ; " bill horn-colour ; tarsi bluish in life, 

 drying olivaceous ; toes black " (H. Saunders). Total length, 

 20 inches; culmen, i'55 ; wing, 12 '3; tail, 5*5; long centre 

 feathers, 7*85; tarsus, 175. 



Adult Female. Similar to the male. Total length, 19-3 

 inches; wing, 12 '8. 



'5 H 



