132 A PRACTICAL HANDBOOK OF BRITISH BIRDS. 



quite so dark and glossy, feathers of breast with more or less tawny 

 edges ; feathers of tibia and tarsus rufous -brown becoming paler 

 and more buffish at base of toes, feathers with dark shafts ; under 

 tail-coverts rufous -brown with variable amount of darker brown 

 mottling, bases white or whitish ; axillaries dark brown with 

 variable amount of rufous-brown ; under wing-coverts dark brown, 

 round bend of wing tawny and fading to whitish ; tail-feathers, 

 tips brown-black (8-12 cm.), rest irregularly banded dark grey and 

 dark brown, paler on edges of inner webs of outer feathers ; wing- 

 feathers brown-black, basal three-fourths of inner webs of 5 or 6 

 outer primaries usually with some whitish streaks, basal part of 

 inner and outer webs of rest of primaries and of secondaries with 

 varying amount of grey-brown or grey mottling usually forming 

 ill-defined bands, paler and often whitish on inner webs ; primary- 

 coverts and greater coverts black-brown mottled grey about the 

 middle and white at base ; median and lesser coverts same but 

 not so blackish and lesser coverts round bend of wing edged tawny 

 or whitish. This plumage is acquired by complete moult and 

 insufficient moulting birds are available to determine exact period, 

 but moult seems very gradual and individuals are scarcely ever 

 in entirely perfect plumage there being always some worn pale 

 feathers. 



Nestling. — At first down (a) white with pale smoky -grey tips, 

 very short down (b) purer white. Later a much longer, thicker 

 and more " woolly " white or creamy-white down (c) replaces 

 down (b) (exactly as in Peregrine, see p. 108). Back of tarsal joint 

 bare and toes bare, otherwise bird very thickly and closely covered. 



Juvenile. — Crown and nape darker and duller, not so " golden " 

 as in adult : rest of upper -parts rather darker than in adult especially 

 tips of lateral upper tail-coverts ; under -parts blacker than in 

 adult, and feathers of breast without tawny edges ; tibia and tarsus 

 not so rufous, tarsus occasionally pure white and often white with 

 brown marks ; axillaries and under wing-coverts more uniform 

 brown -black with little or no rufous ; under -parts show more of 

 the white bases of feathers than in adults ; tail-feathers, extreme 

 tips whitish (soon become worn off), tips for about 10 to 16 cm. 

 brown-black sometimes somewhat mottled greyish, remaining 

 portion of feathers white more or less speckled with brown-black 

 and mottled with grey between the black tip and the base which is 

 uniform white ; outer primaries as adult, inner ones and secondaries 

 white on basal part of inner webs . 



First winter. — Like juvenile. 



First summer. — -The juvenile plumage does not commence to 

 moult apparently until April, is occasionally completed by June, 

 but sometimes not until Oct. Moult complete including wings and 

 tail. When this moult is complete (i.e. when bird is one year to 

 eighteen months), crown and nape much as adult but duller, not 

 so bright rufous -tawny ; rest of body -plumage including upper tail- 



