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blood-vessels which supply the vascular nourishing pulp of the barrel. When this pulp has performed its office, and the stalk and other parts of the feather are fully developed, it shrivels up into the well-known substance, which every one finds in a quill when he cuts it for the purpose of making a pen."*
As in the Mammalia, the classification of Birds into Orders is founded upon the organs connected with motion and food; that is to say, the characters are taken principally from the beak and feet. The subordinate divisions depend chiefly upon the form of the beak, and pass into each other by almost imperceptible gradations, insomuch that there is no other class of animals in which the genera and sub-genera are so little susceptible of definite limitation.
In the present work we shall adopt the Orders enumerated in the “ List of the Genera of Birds" of Mr. G. R. Gray, which are eight in number, viz., Accipitres, Passeres, Scansores, Columba, Galline, Struthiones, Grallæ, and Anseres.
* Penny Cyclop.; Art. Birds.
ORDER I. ACCIPITRES.
(Birds of Prey.) Like the carnivorous quadrupeds, these birds are fitted, by their structure, for a life of rapine. For the most part they feed on living flesh, derived from quadrupeds, birds, reptiles, or fishes, which they pursue and capture by their own strength and prowess. Their natural weapons are not less effective than those with which their mammalian representatives are armed. The beak is strong, crooked, with the point acute and curving downward, and the edges trenchant and knifelike; their feet also are very muscular, and the four toes are armed with powerful talons, long, curved, and pointed, of which those of the hind and innermost toes are the strongest. In the family of the Vultures, however, which feed on the flesh of animals already dead, these characters are much less developed, particularly those which belong to the talons, the true weapons of the more raptorial kinds, the beak being used in both mainly as an instrument of dissecting the food, not of slaying it.
The base of the beak is enveloped in a naked skin, called the cere, in which the nostrils are pierced : the stomach is simple, consisting of a membranous sac without a muscular gizzard. The breast-bone is broad, and in most cases completely ossified, without openings, so as to afford a greater attachment to the muscles of the wings, which are long and powerful. Hence the flight of these birds is usually vigorous, lofty, and long sustained.
Contrary to what usually prevails among birds, the females in this order are one-third larger than the males.. Their eggs are generally pure white, free from spots.
The Accipitres are found in every part of the world. They comprise three well-marked Families, Vulturida, Falconidæ, and Strigidæ.
FAMILY I. VULTURIDÆ.
(Vultures.) We have just observed, that the birds of this Family are not strictly rapacious, inasmuch as their organization unfits them for violence; but their food consists of dead flesh, which in hot countries, where the Vultures chiefly occur, so quickly attains putridity as to have induced the notion that they feed exclusively on carrion. We have proved, however, by personal observation, that decomposition is not a necessary condition of the Vultures' food, for they may be frequently seen regaling themselves on the flesh of an animal within half an hour after it has been killed.
“ The Vulturidæ," observes Sir William Jardine, “have universally been looked upon with a kind of disgust. Ungraceful in form, of loose and illkept plumage, and except when satisfying the cravings of hunger, or during the season of incubation, of sluggish and inactive manners, they present nothing attractive, while carrion being generally mentioned as their common food, associations have been created of the most loathsome character. They are not, however, without utility, for, in the warmer regions of the world, they consume the animal remains, which, without the assistance of these birds, the more ignoble carnivorous quadrupeds, and the myriads of carcase-eating insects, would soon spread pestilence around.” *
The beak, in the Vulturide, is somewhat lengthened, and curved downward at the point: the talons are comparatively weak, and but slightly hooked: the head, and sometimes the neck, in a greater or less degree, are naked, or clothed only with a thin down; as is also the skin that covers the stomach. The wings are powerful and ample, and the general plumage is remarkably stiff and coarse.
* Nat. Lib.-ORNITHOLOGY, vol. i. p. 91.
The Vultures are widely scattered over the globe, but most abound in the regions that lie between the tropics. There they may generally be seen at all times of the day, soaring on motionless wings at a prodigious elevation, wheeling round in large circles with a peculiarly easy and graceful flight, as they reconnoitre the distant earth below. The senses of sight and smell they possess in great perfection, and notwithstanding the assertions of Mr. Audubon, that the former only is put in requisition by them, there is abundant evidence that these birds are guided to their food by the olfactory organs, as well as by those of vision.
GENUS SARCORAMPHUS. (DUM.) In this genus, which is confined to America, and comprises but three species, the beak is large and strong; the nostrils are oval, and placed longitudinally at the edge of the cere; the latter, as well as the forehead, is surmounted by a thick and fleshy comb or caruncle; the third quillfeather is the longest; the hind toe is very short.
We illustrate this genus by the far-famed Condor of the Andes, (Sarcoramphus gryphus, Linn.), which, owing to exaggerated reports of its dimensions from the early European travellers, was formerly supposed to be identical with the fabu