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been supposed that they may be of use to the from all other classes of animals. To this class creature in enabling it, with less exertion of wing, to belong all animals, except Bats (q. v.) alone, which float in the air, but this notion is perhaps sufficiently have an internal skeleton, and are capable of true confuted by the total absence of them in the female. flight. The anterior extremities of B. serve them -In other species, there are elongated feathers on only as wings or organs of flight, and never in any the back of the neck, which the bird can erect, and degree as arms or legs; those few birds in which even in some measure throw forward at pleasure; the wings are too small to raise the body in the air, and these, in the genus Lophorina, assume a form generally employ them to aid their swift running resembling that of a pair of outspread wings, and upon land, as the ostrich, or for swimming under rise far above the head. The tail is, in general, not water, as the great auk and the penguins. unlike that of a crow in its shape; but in many body is covered with feathers (q. v.), and this is species there arise, from the rump, at the sides of one of the characters in which all birds agree, and the tail, two very long feathers, or rather filaments, by which they are distinguished from all other covered with a sort of velvety down: of these, the animals. The general form is adapted to motion Common B. of P. affords an example. In the King through the air, and the trunk is compact, and B. of P. (Cincinnurus regius), these long tail-fila- somewhat boat-shaped, The vertebral column posments terminate in a sort of disk, as the tail-feathers sesses little flexibility ; indeed, the vertebræ of the of the peacock do.
back generally become ankylosed or firmly united Birds of P. are, in general, more or less gregari- together by cementing bone, the solidity which is ous. They sometimes pass in flocks from one island thus acquired being of evident use for the support of to another, according to the change of seasons, the ribs, and these also are proportionately stronger from the dry to the wet monsoon. Owing to than is usual in quadrupeds ; each of them is protheir plumage, they fly more easily against than vided in the middle with a flattened bony process, with the wind, and by high winds they are some- directed obliquely backwards to the next rib, so times thrown to the ground. They are lively and that they support one another, whilst instead of active, and in confinement pert and bold. They being united to the sternum, or breast-bone, by bestow great care upon their plumage, and sit cartilages, as in quadrupeds, they are continued to it always on the perches of the cage, so that no in the form of bone; all these things combining to part of it may reach the floor, or get in the give strength to that part of the body in which it least degree soiled. It has seldom been found is particularly needed, both in order to the powerful possible to bring them alive to Europe, and they action of the wings, and the perfect freedom of seem very incapable of enduring any other than a respiration during flight. In those birds, however, tropical climate. In confinement, they are easily which do not fly, the vertebræ of the back retain fed on rice, insects, &c. In a wild state, their food some power of motion. The hinder part of the consists in great part of the fruit of the teak- vertebral column exhibits a solidity even greater tree, and of different species of fig, and also of than the anterior part of it, the lumbar vertebræ the large butterflies which abound in their native (q. v.) being consolidated into one piece with the islands.
pelvis (q. v.), which furnishes attachment to strong • The Papuans kill Birds of P. by shooting them muscles for the support of the trunk upon the legs, with arrows, and employ various other means of and for the motion of these organs. The vertebral taking them for the sake of their skins. The column, however, terminates in a number of small skins are dried in smoke, and fumigated with sul-movable (coccygeal) vertebræ, the flexibility of this phur, to preserve them from insects; and in this part being necessary to the motion of the tail, which way the brilliancy of the colour 'is impaired, so is itself supported by a short and generally much that the most gorgeous plumes which are ever elevated bone, regarded as consisting of ankylosed seen in Europe are inferior, in this respect, to those vertebræ, called the rump-bone, or, from its peculiar of the living bird. The skin, to which great part form, the ploughshare-bone. of the flesh is allowed to remain attached, is always In contrast to the general stiffness of the vertemuch contracted by this drying process, and a very bral column in the trunk, it is remarkable for great erroneous notion is therefore often formed of the flexibility in the neck, enabling a bird to make ready size of the bird. The common B. of P. is as large use of its bill, or to bring its head into such posias a jay. It is of a cinnamon colour, the upper part tions as suit the adjustment of the centre of gravity of the head and neck yellow, the front and throat in flying, standing, &c. emerald green, the shoulder-tufts yellow.
The number of vertebræ in the neck varies from whole length to the extremity of these is not less ten to twenty-three, the smallest number being than two feet. Another nearly allied species (Para- greater than is found in any quadruped. The head, disea rubra) has these long feathers of a brilliant also, is so articulated to the neck, by a single condyle, carmine colour.
or pivot, that a bird can turn its head round in a
manner impossible to the mammalia. The skull BIRDE, William, a distinguished ecclesiastical
itself is formed of bones corresponding with those of composer, was born about the year 1540, and educated at Edward VI.'s Chapel
. In 1563, he man and quadrupeds; but they can only be distinwas appointed organist in Lincoln Cathedral, and guished when the bird is very young, soon becoming twelve years afterwards organist to Queen Elizabeth. gated, so as to form the bill, the organ chiefly
consolidated together. The jaws are much elongreat musical learning, and contributed many pieces nest-building, dressing or preening the feathers, and
, , to Queen Elizabeth's Virginal Book ; but his fame instead of a 'hand for every purpose which bird-life rests on the canon, Non Nobis Domine, which, amid requires. The upper mandible of the bill is so conall changes in musical taste, has retained its popularity, and still continues to challenge admiration. nected, however, with the bone of the skull, by B. died in 1623.
elastic plates, that it possesses some power of motion,
and any shock which it may receive is much deadened BIRDS (Aves), the second class of Vertebrated before reaching the skull. The bill affords many of (q. v.) Animals, and the first of oviparous vertebrated the most important distinctive characters of B., animals, including all the oviparous animals which differing very much according to the mode of life of have warm blood. B. exhibit great similarity in different orders and tribes. See Bill. their general structure, and are sharply distinguished | The following illustration will serve to indicate
the principal bones of a bird's skeleton; we borrow fly. The clavicles or collar-bones, also, are generally it from M‘Gillivray's British Birds.
united to form the fourchette ( furcula) or merryThe sternum or breast-bone in B. is remarkably thought bone, serving, alor.g with two bones called large and strong, serving for the attachment of the the coracoid bones, to keep the shoulders separated,
and to resist the compressing tendency of the action 6
of the wings. The bones of the wing itself are regarded as corresponding to those of the anterior extremities in man and quadrupeds; the bones of the hand, however, being much disguised, and some of
them wanting or rudimentary. In the accompanying d
cut of the bones of a bird's wing, a is regarded as the elbow-joint, b as the wrist-joint, c as the knucklejoint, d being the representative of a finger, e and f the rudimentary representatives of two others, whilst the winglet, g, formerly regarded as representing the
thumb, is now rather supposed to be homologous to d
the forefinger. The wings, therefore, exhibit a structure entirely different from those of bats, in which the fingers are extremely elongated. The surface necessary for striking the air is provided by feathers larger and stronger than those of other parts of the
body, called wing-feathers, quill-feathers, or quills. j
Of these, which exhibit an admirable combination of
strength with lightness and elasticity, some spring Dell
from the part of the wing between b and d (in the figure of the bones of the wing); these are always the largest, and are called the primary wing-feathers, or simply primaries ; those which spring from the part between a and b are called secondaries; and those which spring from the part between a and the shoulder-joint, are called tertiaries. At the base of the quills, on both sides of the wing,
are feathers called wing-coverts, and these are like3 따
wise distinguished as primary, secondary, &c. The 2
feathers which grow over the shoulder-blades are 3
called scapulars. The feathers of the wings vary Skeleton of Golden Eagle:
in length and strength, according to the mode of life
d a, cranium; b, upper mandible; c, lower mandible; d, d, vertebræ; é, e, ribs; fgh, sternum ; i, coracoid bone; jj, furcula; k, scapula; ů, humeral bone; mm, ulna; in, radius; o, metacarpal bones; p, q, united sacrum and pelvis; r, ischium; 8, ilium; it, thigh-bone; uu, tibia; 0, ankle-joint; ww, tarsus; 1, first or hind toe ; 2, second or inner toe; 3, third or middle toe; 4, fourth or outer toe.
a powerful muscles which depress the wings, and
6 receives great attention from naturalists, because its
Bird's Wing, shewing Quills: variations correspond with the differences in some of
a, primaries; b, secondaries; c, tertiaries; d, winglet. the most important characters and habits of birds. It generally exhibits a projecting ridge along the and power of flight in different B.; narrow, sharp, middle, which is proportionately largest in birds of and stiff wings being indicative of swift and enduring
flight. The tail-feathers serve the purpose of a rudder to guide the bird, and also that of balancing it in the air; they resemble in character the quills of the wings. They are also furnished with coverts above and below. Some B. have the tail rounded at the extremity ; in some, it is square ; in others, notched or forked. In many land B., the tail exhibits ornamental plumes, and remarkable developments of the plumage take place also in other parts of the body, in the form of crests, ruffs, shoulder-tufts, &c.
The legs of B. consist of parts corresponding to those found in man and quadrupeds; but the thigh is short, and so concealed within the body, that it is not apparent as an external portion of the limb; the next division, often mistaken for the thigh, being the leg strictly so called, or tibia, which ends at what is really the heel-joint, although popularly regarded as the knee; and beneath this is the shank, or tarsus, which in some B. is very long, serving as a part not of the foot but of the leg, and formed by
a single bone which represents both the tarsus ang Skeleton of Bird's Wing.
metatarsus. The feet are divided into toef, which
are generally four in number, three before and one most powerful flight, and is wanting only in ostriches behind, differing from each other in length and in and a few other birds of allied genera which do not I the number of joints or phalanges of which they
are composed, the toe, which is directed backward, Few B. masticate their food in any degree, although being in general comparatively short, and consisting parrots do; upon being swallowed, it enters the only of two joints. A fifth toe or tarsal spur is crop or craw, sometimes called the first stomach, an found in some of the gallinaceous B.; and in some enlargement of the oesophagus or gullet, situated B., as Bustards, the hind-toe is wanting: the ostrich just before the breast-bone, and here it is moistened has only two toes, both directed forward, with the by a secretion, which is also by some B.-particuobscure rudiment of a third ; and numerous B. larly by pigeons-employed as the first food for classed together in the order of Climbers (q. v.) or their young, the glands of the crop enlarging very Yoke-footed B., including Parrots, Cuckoos, Wood- much, so as to produce it in large quantity at the peckers, &c., have two toes before opposed by two time when it is wanted for that purpose. The crop is toes behind, the foot being thus particularly adapted wanting in the ostrich, and also generally in B. that for grasping, so that parrots, as is well known, even feed on fish; and is of greatest size in those of which use it as a hand.-The feet of B. vary considerably the food consists of seeds or grain. It is generally according to their mode of life; and naturalists single, and on one side of the gullet; sometimes, as therefore depend very much upon them in classifi. in pigeons, it is double. A second stomach, or dilacation. In some the claws are strong and hooked; tation of the esophagus, called the proventriculus or in others short, straight and weak'; in some the ventriculus succenturiatus, is generally largest in those toes are all separate, in others more or less con- B. in which the crop is wanting or small; and in nected; in B. specially adapted for swimming, they this the food is further softened and changed by a are generally webbed or united by a membrane; in secretion which is mixed with it. The third and other swimming-B., however, a membrane only ex- principal stomach is the gizzard, which in B. of prey, tends along the sides of each toe. In most B. the fish-eating B., &c., is a mere membranous sac ; but tarsus is feathered to the heel-joint; in some, how- in B. which feed on grain or seeds is very thick and ever, and particularly in widers, the lower part of it muscular, so that it acts as a sort of mill, and with is bare; the shank and toes are generally, although extraordinary power. In these B., also, a remarkable not always, destitute of feathers, and are covered provision is made for the perfect grinding down of with a scaly skin. Almost the only other parts of a the contents of the gizzard, by the instinct which bird often destitute of feathers, are the cere at the leads them to swallow small rough pebbles or grains base of the bill, and the combs and wattles of gal- of sand, an instinct well exemplified in the common linaceous birds.
domestic fowl.—The liver of B. is, in general, very In order to flight, it is indispensable that the large. The kidneys are large, but there is no urinary centre of gravity of a bird should be under the bladder, and the urine is at once poured into the shoulders; and when a bird stands, the feet are cloaca, an enlargement of the intestine, at its terbrought forward, and the head thrown back, so that mination, with which also the organs of generation the claws project beyond a vertical line passing communicate in both sexes. We are again indebted through the centre of gravity of the whole body. to M'Gillivray's excellent work for the following cut. This is generally accomplished so that the trunk is in an almost horizontal position, the fore-part only a little elevated; but in some B., which have a short neck and short legs, an erect attitude is necessarily assumed, so that the penguins of the southern seas
D present to navigators a somewhat ludicrous resemblance to regiments of soldiers on the beach. B., when they sleep, very generally place their head under their wing, and some of them also stand upon one foot, their equilibrium being thus more easily maintained. A remarkable contrivance, particularly to be observed in storks and other long-legged B., renders this posture unfatiguing; a locking of the
d bone of one part of the limb into a sort of socket in the bone of the part above it, so that it retains its place without muscular exertion; whilst a similar purpose is served by the tendons of the muscles which bend the claws passing over the joints of the leg in such a manner as to be stretched by the mere pressure there when the weight of the bird rests upon the legs, so that without any effort the claws retain a firm hold of the branch upon which it is perched.-Flying is accomplished by the action of the wings upon the elastic and resisting air; the muscles by which the stroke of the wing is given are powerful, those by which it is retracted are compara
4 tively weak. Owing to the manner in which the first strokes of the wing must be given, few B. rise with facility from a level surface; and some of them, as swallows, and particularly swifts, rise from perfectly level surface with great difficulty, and
Digestire Organs of Domestic Pigeon : comparatively seldom alight where they cannot a, bill; h, head; C, oesophagus; de, crop of extreme size; , find an elevation from which, as it were, to throw
continuation of esophagus; &, proventriculus; hijkl, giz.
zard; h, upper muscle; i, j, lateral muscles; k, lower themselves.
muscle; 1, tendon; mnopar, intestine; 8, trachea. The digestive apparatus of B. resembles that of mammalia; exhibiting, however, various modifica- The respiration of B. is very perfect, and their tions, according to the different kinds of food-some blood is from 12° to 16° warmer than that of manB. feeding on flesh, others on fish, others exclusively malia ; its circulation more rapid, and the energy on insects, others on seeds, others more indiscrimin- of all the vital processes proportionally great. B., ately on a variety of animal and vegetable substances.' consequently, exhibit great liveliness; and upon the
admirable provision for the aëration of their blood | The rapacious B., and particularly the larger ones, they depend also for their powers of flight, which are very solitary in their manner of life. enable some of them to travel hundreds of miles B. change their feathers (moult), in general, once a with great rapidity and without exhaustion, whilst year, and the colours of the plumage in many cases others soar to a prodigious height in the air. The vary much in summer and winter. The change of heart resembles that of the mammalia in its form colour, however, often takes place without change of and structure; but the right ventricle, instead of a feathers, and in B. which moult both in spring and mere membranous valve, is furnished with a strong autumn, the autumn moulting is much more complete muscle, to impel the blood with greater force into than that of spring. The gayest plumage of many the lungs. The lungs are small, and communicate B. is assumed at the breeding-season, with which, with large air-cells (q. v.) in the cavities of the body, also, the song of B. is connected. See Song of and even in the bones, so that the aëration of the Birds. The plumage of the male is, in general, more blood takes place not only in the lungs but during gay than that of the female, all the young at first its circulation through the body. An extraordinary resembling the female in plumage. The plumage proof of the use of these air-cells in respiration was usually characteristic of the male is occasionally afforded in a recorded instance of a large sea-fowl, assumed by the female, and most frequently by which, when an attempt was made to strangle it, females which have become unfit for the ordinary was kept alive by the air entering in a forcible cur- functions of their sex. rent through a broken wing-bone. (Gosse, The The brain in B. differs in some important respects Ocean, quoting Bennett's Whaling Voyage.) B. con- from that of mammalia (see Brain), presenting resume much more oxygen in proportion to their size semblances to the brain of reptiles and fishes; but than quadrupeds.
it is of large size, often larger than even in quadThe organs of the senses are similar to those of rupeds. The manifestation of intelligence is not, mammalia. In the senses of touch and taste, it is however, usually so great in B. as in quadrupeds. generally supposed that there is an inferior develop- Their nest-building, their migrations (see Birds of ment, although parrots appear to possess the sense PASSAGE), and many other things of greatest interest, of taste in considerable perfection; and the bills of must be ascribed to instinct. some B. which search among the mud for their In the geographical distribution of B., the limits food, are certainly very delicate organs of touch. of species are not so exactly circumscribed by mounBut the sight is remarkably keen, and the eye tains, seas, and rivers, as in other classes of animals, possesses great powers of accommodation to different their powers of flight enabling them to pass over distances. B. perceive even small objects distinctly, these obstacles. Yet some species, and even groups, at distances at which they would be quite indis- are found exclusively in certain regions : thus humtinguishable to the human eye, and thus are enabled ming-birds are all American, penguins are found only to seek their food. B. of prey also appear to possess in the southern seas, and B. of paradise are confined in great perfection the sense of smell. The nostrils to New Guinea and the neighbouring islands. See of all B. open on the upper surface of the bill. SPECIES, DISTRIBUTION OF. Hearing is acute in B., and particularly in nocturnal The free movements of B. through seemingly B., although the organs of this sense are less com- boundless space, the joyous song of many, and the plicated than in mammalia, and there is seldom any characteristic tones of all—their brilliant colours, vestige of an external ear. Singing-B. are extremely their lively manners, and their wonderful instinctssensitive to differences of pitch. The voice and have from the earliest ages made a strong impresmusical powers depend upon the conformation of sion on men's minds, and in the infancy of intellect the windpipe and larynx, which differs very much gave rise to many peculiar and mysterious associain different birds.
tions with this class of creatures. Hence the flight Reproduction takes place by eggs (see REPRO- of B. was made the foundation of a particular art of DUCTION and EGG), which are hatched after they divination. See AUGURIES and AUSPICES. Religion have passed from the body of the mother. B. borrowed many of its symbols from them, and poetry generally sit upon their eggs, their bodies sup- many of its ornaments. plying the warmth necessary to hatch them (see In an economical point of view, B. are very HATCHING); and this office is usually undertaken important. The flesh and eggs of almost all B. may by the female alone, but sometimes is shared by be eaten, although those of B. of prey and of fishthe male. In very warm climates, the ostrich eating B. are generally reckoned unpleasant. Their leaves her eggs to be hatched by the heat of the feathers are employed for various purposes of use sun, but in colder climates sits upon them. A and ornament; their dung is valuable for manure, very few B., as the cuckoo, deposit their eggs in and guano (q. v.) is nothing else than the accumulated the nests of other B., to be hatched by them. Some dung of sea-fowls. Many B. are extremely useful in B. construct no nest, but lay their eggs on the preventing the multiplication of insects and worms, bare rock, as many sea-fowl do, or in holes rudely and compensate in this way for the mischief which scratched in the earth or sand; many, however, they occasionally do in fields and gardens. Domestic shew in the construction of their nests the most poultry are a source of considerable profit, upon admirable instincts. See NESTS OF BIRDS. The account of their eggs, flesh, and feathers. See number of eggs varies, in a state of nature, from 1 Poultry. Some kinds of B. of prey have been to about 20, being generally smallest in the larger tamed, and trained to the use of the sportsman. See B., and particularly in B. of prey. B. generally Falconry. breed only once a year, but some B. twice. The About 5000 existing species of B. are known. care which B. take of their young is as admirable as As to their systematic arrangement, see Ornithothe ingenuity which they display in vest-building, LOGY. and more universal. Some B. are able to run about, The order of B. presents in the Dodo (q. v.) a reand pick up food as soon as they leave the shell; markable and well-ascertained instance of the recent others remain in the nest for days, or even weeks, and extinction of a species, and even of a genus. It must be supplied with food by their parents. Many is also a remarkable and interesting fact, that the species are social, particularly at the breeding-season, greater part of the remains of extinct B. hitherto and form large settlements, which they guard in discovered are those of land B. destitute of the power common; and some even unite in the construction of flight, like the dodo, and the still existing ostrich, of large nests, which belong to a whole community. I cassowary, emu, and apteryx. A particular interest