466 STEKCORARIID^ 



of Arctic Europe, 1 Asia, and America : unlike the Arctic 

 Skua, it is only a visitor to the Faroes and Iceland. Its 

 migratory range in winter extends to Southern Europe, 

 and to latitude 40 N. on the Atlantic side of America, and 

 20 N. on the Pacific side. 



DESCRIPTIVE CHARACTERS. 



PLUMAGE. 2 Adult male nuptial. Top of head, upper 

 half of cheeks, and back of neck, brownish-black ; lower 

 cheeks and rest of neck, huffish-yellow ; back, scapulars, and 

 long central tail-feathers, of a greyer shade than those of 

 the Arctic Skua ; wings (including primaries), and lateral 

 tail-feathers, dark brown ; lower throat and breast, white ; 

 abdomen, greyish-brown. 



Adult female nuptial. Similar to the male plumage, but 

 the central tail-feathers are shorter. 



Adult winter, male and female. Similar to the nuptial 

 plumage, but with a tendency to striations on the flanks, 

 and on the upper and under tail-coverts, in birds not quite 

 mature. 



Immature, male and female. Barred on the back, wings, 

 breast, abdomen, and tail-coverts, with greyish-brown and 

 white. The young of the first year vary in tint, especially 

 about the abdomen. They are greyer and less rufous than 

 examples of the Arctic Skua. The readiest distinction 

 between the two species at any age is to be found in the 

 shafts of the primaries. Thus in the Arctic Skua these are 

 all white, whereas in the Long-tailed Skua they are all 

 brownish save the two outer on either side (Saunders). 



BEAK. Dark horn-colour. 



FEET. Greenish-grey ; toes black ; webs of young, parti- 

 coloured, being darker near their extremities. 3 



IRIDES. Dark brown. 



1 Breeds abundantly during some seasons on the Fells of Lapland, 

 where it preys mainly on Lemmings. 



2 In the 'Ibis' for 1865, p. 217, Professor Newton describes an 

 instance of dimorphism in this species, though normally it is very much 

 less marked than in the last-named bird. 



3 The webs in the young of the Arctic and of the Pomatorhine Skuas 

 are also parti -coloured. 



