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Revised Arrangement of the Ornithological System of Cuvier and Dumeril, with reference only to the Genera and Species of the British Islands.

BIRDS are vertebral and oviparous animals, with lungs and warm blood, producing their young enveloped in a calcareous shell, requiring a heat of 100° Fahrenheit to mature their formation. In other respects there is a great analogy with the mammiferous class of animals.

Their bones are generally hollow, containing air; their lungs are attached to the ribs, perforated externally, by which this fluid is distributed through every part of the body, but chiefly into two large membranaceous vessels, or sacs, situated in the thorax and abdomen, by which the body is much enlarged, and rendered considerably lighter. This provision of air affords, in some degree, an additional power of respiration and vigour. It is even supposed that the increased temperature which birds acquire during incubation, and the extensive flights they are enabled to undertake in their periodical migrations, depend much upon the action of air on the blood. It has been ascertained that two sparrows consumed, in a given time, as much air as a guinea-pig.

They sleep resting on one foot, the weight of the body being sufficient to act upon a series of muscles, extending through the thigh to the extremity of the toes, which, in proportion to the pressure of the body, contract and adhere to the perch on which they rest.

The neck is amply supplied with vertebræ moving in all directions, but in the back-bone they are connected and motionless. The breast-bone, with which the muscles of the wings are connected, is of considerable size and strength; it is composed of five parts; the degree of ossification in the posterior lateral pieces is proportioned to the power of flight in each species.

The wing is divided into three principal parts,-the shoulder (brachium), the arm (cubitus), the hand (carpus). The feathers on the hand are always ten in number, called Primary; those on the arm, Secondary; those on the shoulder, Scapulary; those on a small projection from the hand form what is called the bastard wing.

The tail usually consists of twelve feathers, sometimes ten or fourteen, and in the gallinaceous order, eighteen.

The senses of touch and taste must be very weak, the claws and feet being covered with a hard skin, approaching in some species to a horny or scaly substance; but the deficiency in these two senses is compensated by great acuteness in the remaining three.

The eye is furnished with a thin membranaceous veil, which the bird can draw and remove at pleasure, easily discernible in the hawk tribe. Its probable use is to guard the eye in rapid flights, or to moderate the effect of light. By a peculiar additional mechanism, birds are also enabled to regulate the sight for near or distant vision.

The digestive organs merit particular notice. The throat terminates in a large membranaceous bag, called the crop*. Here the food is collected and softened, preparatory to its passing into the gizzard, where it is reduced to a pulp. This organ consists of two very powerful muscles, lined and covered with a strong tendinous coat, furrowed within. In rapacious birds, the gizzard is, however, wanting, their stomach being nearly allied to those of quadrupeds. The power of this organ almost exceeds belief, it having been proved by experiment, that very hard and sharp substances are unable to resist its action. It has been observed, that stones which birds are in the habit of swallowing are seldom known to pass with the fæces. They, therefore, probably contribute to their health by affording an additional supply of calcareous matter; and digestive organs of this singular character are consequently requisite for the purpose of pulverizing them sufficiently for admission into the system.

The channel conveying air to the breast is called the Trachea, and differs from that of other animals. The organ producing sound is situated immediately below the point where the trachea separates into two channels, and is called the Larynx inferior; so that a bird might emit its characteristic note after decapitation. J. S.

It is of so light and close a texture, that the crops of turkies are prepared and sold in London as small balloons; when filled with hydrogen gas they will rise with great rapidity, and retain the gas for a considerable time, particularly if slightly varnished.

Order I. ACCIPITRES. Rapacious.

One back toe; those in front quite unconnected; beak and claws hooked. Of this order there are two subdivisions.

Eyes...{Lateral, on one side of the head

In front

Plumicolles.
Nocturnæ.

Subdivision 1. Order I. Rapacious.
PLUMICOLLES.

Eyes lateral; base of the beak with a fleshy excrescence called the Cire. 2d the longest; 1st nearly as long; Beak curved from base, and notched at each side, near

Wing feathers

the end

1st very short; 4th usually longest beak

Falco,
Long and straight from base, hooked at the end... Aquila,
Short and curved from base (Longer, or equal to
Wings..
tails, which in kites Buteo,
are forked
Shorter than tails... Accipitres,

The Orders are placed in the above succession on account of the natural distinctions specified; but they are usually enumerated as follows:-1. Rapacious; 2. Passerine, including some of the Pica of Linnæus; 3. Climbers; 4. Gallinaceous; 5. Waders; 6. Webfooted.

Beak awl-shaped; short, weak, flexible, without notches; base narrow and round.

Beak short, slender, without notches; wide and flat at the base.