1^4 BUTEO LAGOPUS. 



Female. — The female, which is considerably larger, 

 is similar in colouring to the male ; but the light-co- 

 loured parts are generally of a deeper tint, or light 

 brownish-yellow, and the lower tail-coverts marked 

 with brown spots. 



Length 23 inches, extent of wings 31 ; bill along the 

 back 11, along the edge of lower mandible 1^^, ; tarsus 



S>1 



^1 -I • 



Variations. — Individuals of this species differ from 

 each other, although not so much as those of the Com- 

 mou Buzzard, yet in a remarkable degree, there being 

 more or less of white or brown, and these colours va- 

 rying in tint, while the broad patch on the breast dif- 

 fers both in depth of colour and in extent ; the tail has 

 sometimes two bars on its brown part, and sometimes 

 has that portion uniform, or merely darker towards the 

 terminal edge. Many other differences might be point- 

 ed out ; but as I have not been able to examine a great 

 number of individuals killed in Britain, I must leave 

 this task to the general ornithologist. It is very re- 

 markable that this bird, which occurs in North Ameri- 

 ca, and has been described by Mr Audubon and others, 

 should there become ultimately of a nearly uniform 

 chocolate-brown, retaining, however, the peculiar marks 

 on the lower surface of the wing. In this state it 

 was described by Wilson and others as a distinct spe- 

 cies, but Mr Audubon, whose specimens I have seen, 

 has clearly shewn it to be the same bird as his Rough- 

 legged Falcon. I am not aware that in this dark plu- 

 mage the bird has been seen in Britain, although it 

 would appear that it occurs in the northern parts of 



