AVES. 305 
which is the vocifer of Le Vaillant (AZ vocifer), the plumage of which, especially 
the white head, gives it somewhat the appearance of the American species. 
Several Indian species also occur, constituting the genera Ichthyiaétus, Lafres., 
Limnaétus, Vig., and Spilornis, Gray, all the species of which seem to par- 
take of general characters and habits. 
In this sub-family we find the ospreys, genus Pandion, one species of 
which is a common and familiar bird upon the North American sea-coast, 
known as the fish-hawk, and much respected as one of the harbingers of the 
fishing season. It builds a large and conspicuous nest composed of a great 
quantity of sticks and leaves, in which it is universally allowed by the people 
upon the coast to rear its young without molestation, though quite the 
reverse is practised towards all others of this family of birds. The Euro- 
pean species, P. ossifragus (pl. 105, fig. 3), is distinct from that of the 
American coast, though very similar, as are others inhabiting various parts 
of the world. 
The harpy eagles, genus Harpyia, Cuv., also belong here. The principal 
species is the great harpy (Haurpyia destructor), which, in addition to a full 
share of other rapacious characters, possesses the most formidable claws of 
all known birds. It subsists on sloths, monkeys, and other quadrupeds. 
Other smaller species belong to this genus which are found in South Ameri- 
ca. Related to these are the very handsome crested eagles of the genus Spi- 
zaétus, Vieill, which inhabit the same country ; the S. ornatis is especially 
beautiful. 
The African short-tailed eagle (Helotarsus ecaudatus) may be especially 
designated, if for no other purpose than merely to mention that although he is 
a bird nearly as large as the bald eagle, his tail is so short as to be scarcely 
discernible without examination. 
The little Pondicherry eagle, or Brahman kite, as it is sometimes called 
(Haliastur pondicerianus), belongs here. It is a small species, with white 
and chestnut colored plumage, and is one of the most common of the Indian 
birds of prey. Many other species are found in various parts of the world. 
They are the largest of the birds of prey of this family, and are only equalled 
in size in the class of rapacious birds by the vultures. 
Sub-fam. 4. Polyborine, or Caracara Eagles. Bill rather weak, and 
but slightly hooked at the tip, lateral margins of the upper mandible festooned 
or sinuated ; wings long, tail long, rounded. ‘Tarsi slender, naked, and covered 
with scales ; feet moderate, rather weak; claws moderate, acute. Face and 
region about the eyes naked. Size small. 
The Polyborine compose a small group of very peculiar birds confined 
exclusively to the warmer parts of America, one species only, Polyborus 
braziliensis, occurring as far north as Mexico, Texas, and occasionally 
Florida. It is rather remarkable for its beauty of plumage, and is said to 
combine the destructive qualities of the hawks with the indiscriminating 
voraciousness of the vultures. In fact these characters are attributed to 
all the species of this group, and are sanctioned by their appearance. 
Their naked faces and comparatively weak bills give them much the 
appearance of the vultures with which they have sometimes been classed ; 
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