PEREGRINE FALCON. 63 



examples were brought by Dr. David Walker, the naturalist 

 of the ' Fox ' expedition), to Mendoza, in the territory of the 

 Argentine Confederation. It may be observed, however, that in 

 the western part of South America, Chili for instance, a Falcon 

 is met with which is much allied to, if not identical with, the 

 F. melanogenys before mentioned. In Greenland, the Pere- 

 grine Falcon not only occurs, but constantly breeds. 



The whole length of an adult Peregrine Falcon is from 

 fifteen to eighteen inches, depending on the sex of the bird. 

 The beak is blue, approaching to black at the point ; the cere 

 and eyelids yellow, the irides dark hazel-brown ; the top of 

 the head, back of the neck, space below the eye and a broad 

 mystacial patch, nearly black; the back, wing-coverts, and 

 tail, bluish- slate or ash-colour, barred with a darker tint ; 

 the primaries brownish-black, the inner webs barred and 

 spotted with rufous-white ; the throat white, with dark 

 longitudinal lines ; the breast rufous- white, with dark brown 

 transverse bars ; the flanks, under tail-coverts, and the 

 tail-feathers beneath, barred transversely with dark brown 

 and greyish-white ; legs and toes yellow, the claws black. 

 The figure here given was taken from a very fine female of 

 large size, in its second year, but still retaining one outer 

 tail-feather of the first year on each side. The wing and 

 tail-feathers are not changed in the Falconldce in their first 

 autumn. 



The young, until the first moult, have the head and upper 

 surface of the body and wing-coverts of a brownish ash- 

 colour, the edge of each feather rufous ; the under side of 

 the body dirty- white, with dark longitudinal streaks ; the 

 tail with irregular reddish bars, the tip white. The cere 

 and eyelids blue ; the feet yellow. The first moult begins 

 in April or May, and proceeds gradually through the 

 summer. 



This species presents very considerable individual varia- 

 tion, though perhaps not to the same extent as the preceding. 

 The birds which are darkest in the immature plumage, are 

 darkest also in the adult stage ; while those which are of a 

 light colour when young, are light when old. The feathers 



