BUFFON'S SKUA. 



361 



form resembling that of the allied species *. In the adult in newly- 

 moulted plumage the general colour o£ the upper parts is greyish brown, 

 almost black on the head, wings, and tail-feathers ; the general colour of 

 the underparts is white, shading into brown on the flanks and under tail- 

 coverts ; the white on the throat extends to the sides of the neck and across 

 the lower ear-coverts to the nape, and is sufl'used with yellow. Bill slate- 

 grey, black at the tip ; legs and feet slate-grey, with irregular black patches ; 

 irides hazel. Young in first plumage are uniform sooty brown, the flank- 

 feathers and the upper and under tail-coverts having buff" margins. 

 Buffbn^s Skua is probably several years before it attains its adult plumage, 

 the Avhite on the underparts gradually increasing from year to year. 

 Young in down are sooty brown, slightly paler on the underparts. 



* Dresser, in his ' Birds of Europe,' says that Middendorff " mentions that BufFon'a 

 Skua was subject to as much and similar variations as the Pomai'ine Skua on the under- 

 parts of the body." This statement is not true, and is no doubt founded on a mistrans- 

 lation of a passage where Middendorff says that exactly the same variation in the colour 

 of the belly occurred in Richardson's Skua as in the Pomarine Skua, and under the same 

 circumstances. These circumstances are explained to be that the white-bellied birds had 

 long^er centre tail-feathers than the dark-bellied. 



Vol. Hi. 



2b 



