AVES FALCONID^. 565 



crown almost touches the lower part of the back. This fact, which has 

 been doubted, is true ; for I have myself several times seen them with 

 their heads backwards, in completely inverted position. The Carrancha 

 builds a large coarse nest, either in a low cliff or in a bush or lofty tree. 

 To these observations I may add, on the high authority of Azara, whose 

 statements have lately been so fully confirmed by M. D'Orbigny, that the 

 Carrancha feeds on worms, shells, slugs, grasshoppers, and frogs ; that it 

 destroys young lambs by tearing the umbilical cord ; and that it pursues 

 the Gallinazos and gulls which attend the slaughtering houses, till these 

 birds are compelled to vomit up any carrion they may have lately gorged. 

 Lastly, Azara states that several Carranchas, five or six together, will unite 

 in chase of large birds, even such as herons. All these facts show that it is 

 a bird of very versatile habits and considerable ingenuity." 



In his Natural History of the Straits of Magellan (1871, pp. 133-134), 

 Cunningham says: "In the course of our expedition we observed a few 

 snipe and many large carrion-feeding hawks. These birds, the carranchas 

 [Polyborus t/iariis), are extremely common on the grassy plains, and their 

 vulturine habits, as Mr. Darwin has observed, 'are very evident to any 

 one who has fallen asleep on the desolate plains of Patagonia ; for when 

 he wakes, he will see, on each surrounding hillock, one of these birds 

 patiently watching him with an evil eye.' When thus perched, they 

 assume a very erect posture, and I have frequently mistaken one in the 

 distance for a human creature. The plumage is handsome, but the naked 

 skin over the crop, which protrudes after a meal, communicates an un- 

 pleasant aspect to them, and they are exceedingly disagreeable to skin, 

 as they are invariably swarming with minute and very active Anoplura." 



Hudson, writing of the Caracara in Argentina says (P. Z. S. 1870, p. 

 112): "South of the city of Buenos Ayres, the low shore of the river is 

 from six to eight miles in width ; but for more than half this width the 

 portion furthest from the river is frequently inundated, and covered with 

 reeds and aquatic plants. Passing this there occurs a strip of light and 

 dry land, running parallel with the river, composed chiefly of fossil shells, 

 and grown over with a forest of low trees. In some places this high 

 ground is extremely narrow ; in others there are great breaks in it, through 

 which the river passes when greatly swollen. In this strip of forest may 

 be found all the birds inhabiting Buenos Ayres that perch on trees, not 

 even excepting the Pampas Woodpecker [Colaptes campestris), of which 



