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The great size of the beak naturally induces the idea of great weight; and we wonder at the strength requisite for the bird to support and wield
an organ so apparently heavy. The appearance, however, is deceptive; for by a beautiful provision of Creative wisdom, the horny case being thin, and the bony core being hollowed into numberless cells of various sizes and forms, with very thin walls between them, the requisite firmness of this organ is maintained, and associated with a surprising lightness.
The remaining characters of the Family may be thus briefly summed up. The nostrils are situated at the base of the beak, and are more or less rounded; the tongue is fleshy, and resembling that of the Accipitres, short and deep in the throat; the wings are rather short; the tail long, broad, and more or less rounded at the extremity, consisting of only ten feathers; the feet short, strong, and formed for walking and perching;
the outmost and inmost toes are both united to the central one at the base; the claws are short and blunt.
The Hornbills are birds of large size ; few are smaller than a Crow, and some are much larger than a Raven; they are generally clad in sombre plumage, frequently relieved, however, with white in large masses; the beak and naked skin of the face often display bright colours during life. Their distribution is limited to Africa, India, and the great adjacent islands.
The singular structure of these birds, and the paucity of our information concerning their habits in a state of nature, have caused much diversity of opinion as to their true position and affinities. It is now, however, pretty well agreed that their nearest relations are to the Crows on the one hand, and to the Toucans on the other, and that they thus form a very interesting link of connexion between the Passerine or perching and the Scansorial or climbing birds. Professor Owen, by his dissection of a young specimen of Buceros cavatus (Shaw) that died at the Gardens of the Zoological Society, discovered some curious particulars in its anatomy, which tended to indicate the true place of the Family, as just stated.
Genus Buceros. (Linn.) The technical characters of this genus have already been sufficiently indicated in those of the Family; as the two solitary species which have been separated from all the others, to form distinct genera, differ only in some slight peculiarities in the structure of the feet.
Upwards of twenty species of this genus are named, which are all natives of Africa, or India and its archipelago. Comparatively little is known of any of them, except so much as may be gained by inspection of their dried skins préserved in museums; though these evidences of their existence were very early objects of curiosity to Europeans, and conspicuously noted in catalogues, as “Horned Ravens," and “Rhinocerotbirds.” Bontius, describing one under the name of "Indian Raven" (the Buceros hydrocorax of Linn.), which he met with in the Moluccas, observes, that it walks in the manner of the Crow of our countries, but differs much in disposition from our Crows, inasmuch as it feeds not on carrion, but most especially on nutmegs, devouring them so greedily as to do serious damage. Its flesh is very delicate, and when roasted has an aromatic flavour, evidently derived from its food. Of another species, “the Horned Indian Raven, or_Topan, called the Rhinocerot-bird,” he says, “This horned bird, as it casts a strong smell, so it hath a foul look, much exceeding the European Raven in bigness. It lives upon carrion and garbage, that is, the carcasses and entrails of animals; and waits upon the hunters who kill wild cattle, boars, and stags, to gorge itself with the offals.” Major-General Hardwicke, in his account of Buceros galeatus, Linn., in the “Linnean Transactions," vol. xiv., thus describes the habits of the Hornbills generally:-" The progressive motion of the birds of this genus, although their feet are formed for walking, is always by jumping or hopping. I have kept several species alive, and they all moved in the same manner. In a state of nature these birds, in this part of India (Malacca), live on wild fruits. In confinement they feed freely on plantains and on boiled rice. At night they perch with great security, though the largeness of the foot seems better suited to rest on the ground.” Other writers state that these birds feed also upon small quadrupeds, birds, and reptiles, pressing them flat in their beak, then tossing them in the air, catching them in the throat, and swallowing them whole. In this latter habit, no less than in the omnivorous character of their appetite, the Hornbills present a remarkable resemblance to the Toucans.
Mr. G. R. Gray, in his beautiful work on “ The Genera of Birds," thus sums up the habits of this singular genus : — " They are usually observed singly, or in small or large parties, in the dense forests or jungles, perched or squatted longitudinally on the highest branches, especially those of elevated and decayed trees in the neighbourhood of rivers. On the approach of day-light they leave their roosting-places, and proceed to the neighbouring forests in search of fruit-bearing trees, hopping from branch to branch for the fruits which constitute their food; and when evening returns they again repair to the place that they had left at day-light. When they have cleared one neighbourhood of its food, they resort to a fresh locality ; which occasions them to be observed at different periods in various places. .... Their flight is heavy and straight, generally at a considerable height; and they make a remarkable noise in striking the air with their wings. The cry consists of a short hoarse croak, but when the bird is excited this is changed to a
loud discordant noise. They perforate the trunks of trees from the side, making a hollow in the wood, in which the nest is formed; and the female usually lays four eggs.” The noise alluded to in the above description, produced by the flapping of their heavy wings in flight, combined with that occasioned by the clattering of their mandibles, is said to be so great as to inspire terror, when the cause is unknown; and to resemble those flaws of rough and sudden winds, which often rise so unexpectedly in tropical regions, and blow so violently. The larger species are extremely shy, and difficult of approach : like some of the Corvidæ, they usually perch on the leafless branches of the loftiest trees, when their vision, unimpeded by foliage, ranges over a wide extent.
The singular excrescences which in most of the species arise from the beak, sometimes equalling that organ, large as it is, in size, not only in different species vary much in form and size, but even in the same species at different stages of its life; indeed, in very young birds there is no trace of its existence. * The perpendicular furrows which are seen on the sides of the upper mandible, are supposed by the Europeans resident in the Moluccas to be dependent on age, one being acquired every season ; and hence they give the Hornbills the appellation of Jerar-vogel, or Yearbirds. We have remarked on its lightness, owing to its cellular structure, permeated by air; but it is also observable that the bones of the body and limbs are more completely penetrated by this
* The knife-like ridge on the summit of the beak in Crotophaga ani, is in like manner totally wanting in the young bird ; as we have found by personal observation.