48 BIRDS OF LA PLATA 



that grey country* The English colonists on the 

 Chupat, Durnford says, call it the " White Horse/' 

 owing to its conspicuous white colour often deceiving 

 them when they are out searching for strayed horses 

 in the hills* It is a wary bird, and when approached 

 has the habit of rising up in widening circles to a 

 vast height in the air. When sailing about in quest 

 of prey it usually maintains a height of fifty or sixty 

 yards above the surface. The stomachs of all the 

 individuals I have examined contained nothing but 

 the remains of cavies (Cavia australis). 



The nest is built on the top of a thorn bush, and is 

 a large structure of sticks, lined with grass, fur, dry 

 dung, and other materials. The eggs are greyish 

 white in colour, blotched and marked, principally 

 towards the large end, with two shades of umber- 

 brown. 



GREY EAGLE 



Geranoaetus melanoleucus 



Above black, wings grey with narrow transverse black bars ; tail 

 black ; throat grey ; breast black with round whitish spots ; abdomen 

 white ; bill horn-colour, feet yellow ; length 26, wing 19 inches. 



THE Grey or Chilian Eagle, like most diurnal birds of 

 prey, undergoes many changes of colour, the plumage 

 at different periods having its brown, black, and grey 

 stages : in the old birds it is a uniform clear grey, 

 and the under surface white. Throughout the 



