Head and neck more or less bare or only clothed with short stubby down; never any true feathers on crown of head (Sharpe).
The above appears the only really distinctive character by which Vultures are distinguished from Falcons, Eagles, and Hawks. Vultures have the crop covered with short feathers, and generally a more or less distinct elongate ruff round the neck at the end of the naked portion. The bill (except in Neophron) is strong, deep, and compressed, with the culmen much curved ; the tip is always hooked, and the cere large and horny. There are 15 cervical vertebras, or one more than is usual in Falconidae. The wings are long; tail-feathers 12 or 14, with strong shafts, that, owing to wear, always project at the ends. The tarsi are partly feathered, the naked portions covered with granular scales, with larger transverse scutes on the distal phalanges of the toes; the inner and outer toes are subequal, and the middle and outer united by membrane; claws blunt, not much curved.
Typical Vultures (the genus Neophron differs in some respects) resemble each other closely in habits. As is well-known, they feed on dead animals, and congregate in an extraordinary manner wherever a carcase is exposed. The way in which they assemble, apparently from all parts of the air, in a place whore a few minutes previously not one was in sight, is a wonderful spectacle. "When in search of food, Vultures and some other Accipitrine birds soar and wheel slowly in large circles, very often at an elevation far beyond the reach of human vision, as was shown by the observa¬tion of Colonel Tennant, who at Roorkee in 1875 (S. F. iii, p. 419) noticed that birds at a height of some miles often passed across the field of his telescope. As Jerdon and other writers have pointed out, the Vultures are dependent for the discovery of their food upon their eyesight, the more distant birds being attracted by seeing those nearer to the carcase flying in a manner that shows them to have found out its position. The actual discovery is doubtless generally made by Crows or Kites, and the Vultures obtain information from the movements of the smaller birds.
On the ground Vultures are clumsy, heavy, and ungainly, as foul in aspect as in smell; but on the wing no bird has a grander or more powerful flight, and none affords a better opportunity of studying the position and movements of a bird when flying. Amongst the rocky crags to which Vultures resort to roost and, in many cases, to breed, it is often easy to stand on the edge of a cliff where they pass by within a few feet, and as each great bird sweeps past, regulating its course by its tail, and occasionally moving- its head slightly as it investigates the different objects that present themselves, to notice how steady and unchanging is the position of the extended wings and flight-feathers, and to observe how entirely the support of the bird is due to the resistance of the air.
Vultures are confined to the tropical and warm temperate regions of Asia, Europe, and Africa; their American representatives, the Condors and their allies, being now placed in a distinct order by most ornithologists. The family is represented in India by species of all known genera except Lophogyps. By some writers Neophron is regarded as forming a distinct subfamily, but the difference is scarcely more than generic.
Key to the Genera.
a. Bill stout; height of upper mandible approxi¬mately the same as length of cere on culmen.
a1. Nostril round or oval; tail-feathers 12.
a2. No neck-wattle ………………………VULTURE, p. 316.
b2. A fleshy wattle on each side of the neck ………………………OTOGYPS, p. 318.
b1. Nostril a vertical narrow slit.
c2. Tail-feathers 14 ………………………GYPS, p. 319.
d2. Tail-feathers 12 ………………………PSEUDOGYPS, p. 324.
b. Bill slender; nostril elongate, horizontal ………………………NEOPHRON, p. 325.