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fluid than those of any other birds; for Professor Owen found that air passed into the extreme bones of the wing, and into the joints of the toes. The eyelids are fringed with stout and stiff lashes, the object of which may be to protect the eyes
HORNBILL. from particles of dust and rotten wood falling on them, when engaged in excavating decayed trees for the purpose of incubation. The Crotophaga, whose beak presents an analogy to that of the Hornbills, has the eyes similarly protected: this bird, however, does not excavate trees.
We select for illustration of the
the Concave Hornbill (Buceros cavatus, Shaw), a specimen of which lived for sometime at the menagerie of the Zoological Society in the Regent's Park. It is thus described. The throat and face are black; the neck dirty straw-yellow, the feathers of the nape greatly lengthened: the body and wings black, the quills and their coverts tipped with white; the tail white, crossed with a band of black; its coverts, both above and below, are also white. The feet are black, and the beak yellowish, inclining to scarlet at the tip.
The Concave Hornbill is a native of India, the Himalayan mountains, Java, and most of the great islands adjacent. “Its food," observes Mr. Gould, “ like that of other Hornbills, consists of fruits, berries, flesh, and even carrion; in short, it may be considered as strictly omnivorous." * Professor Owen remarks that the specimen dissected by him was observed when alive to be more attached to animal than to vegetable food, and would quit any other substance, if a dead mouse were offered to it. This it would swallow entire, after squeezing it twice or thrice with the beak, and no castings were noticed. Petiver, however, has borne testimony to its habit of regurgitation.
Respecting the purpose to be fulfilled by the great size and remarkable appurtenances of the beak in this genus, we have nothing better to offer than ingenious conjectures: as a specimen of which we may quote the remarks of an eminent zoologist, Mr. W. C. L. Martin, though they do not appear to us very satisfactory.
- Active and alert, notwithstanding the magnitude of their
* Gould's Cent. of Birds.
beaks, these birds lightly traverse the branches of the forests and leap from one to another till the highest is attained: they then often stop and utter a loud roaring sound, which may be heard at a considerable distance. The noise thus uttered, and which is most probably their callnote, throws a light upon the design of the hollow protuberance surmounting the bill; it acts as a sounding-board, increasing the reverberations of the air. With regard to the huge beak itself, many conjectures have been entertained as to its peculiar uses. It has been suggested as a reason for its development, that it perhaps constitutes a necessary weapon of defence against monkeys and other animals, which may seek to assail its nest; while some have supposed that it might be employed in dragging snakes and lizards from their lurking places, or young birds and eggs from the recesses of the trunks of aged trees."*
* Pict. Mus. i. 350.
ORDER III. SCANSORES.
(Climbing Birds.) The association of the Families usually arranged in one group, under the above title, or that of Zygodactyli, or yoke-footed birds, is by most naturalists felt to be unsatisfactory. Unlike in food, in form, in habits, and economy, the single character which they have in common, is that their four toes are arranged in two pairs, the outer toe being turned backward more or less permanently, like the thumb, so that these are opposible to the middle and inner toes, which point in the opposite direction. From this structure results. a more efficient power of grasping, or of clinging to perpendicular or reversed surfaces, associated with climbing habits in the principal Families, as those of the Parrots and the Woodpeckers.
In the other Families, however, those of the Toucans and the Cuckoos, this disposition of the toes is not accompanied with the power of climbing, properly so called; though the latter, and perhaps the former, do certainly move about the branches of trees, in a manner diverse from that employed by the true perching or Passerine birds. At the same time it must be borne in mind that the faculty of climbing, even if common to the whole of this Order, is by no means peculiar to it; as the Creepers and Nuthatches, whose toes are arranged on the Passerine type, can climb and
even run on perpendicular and inverted surfaces with much more facility than any of the so called Scansorial birds.
As so little can be predicated of these birds in common, with the exception of the structural peculiarity above-noted, we defer the summary of habits and economy, until we define the respective Families which are included in the order. These are four in number, Rhamphastidæ, Psittacidæ, Picidæ, and Cuculidæ. Of these, the first is confined to the southern portion of the New World ; the others are spread widely over both hemia spheres.