238 Proceedings of the Royal Phijsical Society. 



flight is not strong enough to kill a bird on the wing. In 

 the Argentine Eepublic, it performs a partial migration, 

 flying northwards in winter. Mr Gibson mentions its great 

 familiarity in that country, as shown by its hovering over, 

 or alighting within a yard of the place, where an animal is 

 being flayed. It is stationary at Tala. 



A clutch of three eggs, taken 6th October 1879, from a nest 

 placed in a clump of thick grass in the campo ; nest unlined 

 save with grass stems. 



Another clutch of three eggs, taken on 10th October 1879, 

 from a similar nest, in a like situation. 



The eggs of three clutches, nine in all, average l-f-g- x 1^^ 

 inch. 



They usually lay three eggs, which cannot be better de- 

 scribed than as resembling, in their different varieties, those 

 of the kestrel, being, however, somewhat larger. They are 

 figured by D'Orbigny. 



3. Polyhorus thanes (Molina) — the Southern Caracara 

 Eagle : native name " Carrancha." — The Carrancha, one of 

 the most abundant of South American raptors, though a 

 noble looking bird, and bearing the name of eagle, is more 

 akin to the vultures, rarely killing any animal for itself, but 

 feeding on carrion, although, according to Azara and Audubon 

 it will eat worms, slugs, grasshoppers, frogs, and even young 

 alligators. Like the chimango, it steals chickens, and occa- 

 sionally accompanies the sportsman, and steals the game he 

 shoots, ere he has time to secure it. Like the secretary bird 

 of Southern Africa, it is also fond of snakes. It is found 

 throuohout almost the whole continent of South America to 

 the Straits of Magellan, and is replaced in the Southern 

 States of North America, and in Mexico, by an allied species. 

 Darwin states, that if one falls asleep in the plains of South 

 America, he wHl, on awaking, find one of these birds 

 sitting on each rising ground near, patiently watching him 

 with an evil eye. Its fiight is heavy, except in the evening, 

 when returning to its nest, and its cry loud and disagreeable, 

 and when uttering it, it throws its head higher and higher 

 until the top nearly touches the back. Although feeding in 

 company with the last species, they are far from friendly, 



