CARRION BUZZARDS. 301 



between the inner and middle toe, as well as between outer and middle, as in most 

 other Falconidae except the osprey. In addition to this, the bill is not usually toothed 

 (the only exception being in Milvago, where there is a trace of a tooth) ; the legs are 

 rather long, tarsi little feathered in front above, mostly reticulate, or with small scales, 

 only really scutellate just above the toes, in front ; the hind toe much shorter than 

 any of the others, which are variable in length. The sides of the head are also more 

 or less destitute of feathers. Two or three of the species reach the size at which most 

 buzzards gain popular recognition as eagles, but the others are smaller. 



The species have been rather naturally grouped in three genera, namely, Polyborus, 

 with one or two species, Milvago, with five or six, and Ibycter, with two. Polyborus 

 and Milvago are chiefly terrestrial ; Ibycter completely arboreal. The legs in all are 

 decidedly long, the toes short in the terrestrial forms, longer in the arboreal. The 

 bill of Polyborus is much the strongest, being high, laterally compressed, and with 

 narrow, almost linear nostrils, while the other genera have the bill of a more ordinary 

 type, and the nostrils circular. In all the genera there is a patch of naked skin over 

 the crop, not noticeable, however, Avhile the crop is empty. There is also more or 

 less unfeathered and often brightly colored skin about the face. This is least noticea- 

 ble in Milvago chimango, more prominent in the other species of Milvago and in 

 Polyborus, and reaches its maximum in Ibycter americanus, where not only the face 

 and sides of head are bare, but also a large part of the throat. 



The caracara eagle, Polyborus tharus, is an abundant bird all over South America, 

 and one of its races extends as far north as Texas and Florida. It is strongly and 

 rather clumsily built, spending much of its time on the ground, where it walks about 

 easily in search of food. On the wing it does not usually give the impression of much 

 strength or skill, but it does often rise to a great height, and during the pairing 

 season frequently goes through a variety of aerial evolutions. It feeds on animal 

 matter of any kind, freshly killed or putrid, is often seen associating with the vultures 

 ( Cathartes), and, like them, not unfrequently attacks weak or sickly animals. On the 

 plains of La Plata it is hated and detested by the sheep farmers for its habit of 

 attacking new-born lambs, many of which, in spite of every precaution, are annually 

 killed in this way. Darwin says of this species : " Their vulture-like, necrophagus 

 habits 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. . . . j^t times the carrancha is noisy, 

 but is not generally so ; its cry is loud, very harsh, and peculiar, and may be likened 

 to the sound of the Spanish guttural g, followed by a rough double r ; when uttering 

 this cry it elevates its head higher and higher, till at last, with its beak wide open, 

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

 doubted, is quite true ; I have seen them several times with their heads backwards in 

 a completely inverted position." To this we may add that although this last singular 

 fact is confirmed, if confirmation were necessary, by many other observers, it can 

 scarcely be a very common performance, since we ourselves, during an uninterrupted 

 acquaintance of about eighteen months with this bird, never saw more than a slight 

 elevation of the head while its cry was uttered. 



It makes a bulky nest on low or medium-sized trees, and lays two or three hand- 

 some, brown-spotted eggs, very variable in precise color and amount of markings. 

 The general color of the caracara, or carrancha, as it is called on the Plata, is 

 blackish brown above, with fine cross-bars of black and grayish white below. The 



