Ornithology (Gr., bird, and, discourse), the department of zoology which treats of the structure, habits, and classification of birds, the second class of vertebrated animals. Fur their structure see Birds. Until after 1825 most ornithologists classified birds according to the characters of the bill and feet; since then several authors, especially Oken, Nitzsch, Sundevall, Müller, Cabanis, Bonaparte, and Burmeister, have drawn attention to the care they take of their young, the song and the vocal muscles, the number and length of the quills, the scales and feathers on the legs, the number of tail feathers, the position of the hind toe, and the absence, presence, and extent of the webs, as data for a natural classification. - Aristotle, in the third chapter of his eighth book on animals, mentions the modes in which birds subsist, that some are carnivorous, others granivorous, and others omnivorous; that some are terrestrial and others aquatic, and many migratory during winter; he enumerates the names of the species then known, without descriptions except for the eagles. - Belon, the reviver of natural history, in his Histoire naturelle des oiseaux (fob, Paris, 1555), classed birds by their habits and the places where they are found, making the four divisions of birds of prey, waders, swimmers, and birds which nestle in trees or on the ground; his work is illustrated with numerous woodcuts.
Aldrovandus, in his Omithologia (Bologna, 1599-1006), follows Belon in classifying birds according to their places of habitation and the nature of their food, but adds a great number of new descriptions. The work of Willughby, Ornithologioe libri tres (London, 1676), was the first systematic attempt at classifying birds; in this the land birds are divided into two groups, one having curved beak and talons, the other with the bill and claws more nearly straight; the water birds are also subdivided into waders and swimmers. Ray, in the Synopsis Me-thodica Avium (8vo), published in 1713 after his death, made some improvements upon Willughby's system; and these two furnished the basis of the classification adopted by Linnaeus. - In the 12th edition of the Systerna Naturoe (1766), Linnams divided the class into six orders:
Accipitres Or Birds Of Prey, with the bill bent, and the upper mandible dilated on each side or armed with a tooth; legs short and robust, toes warty, and claws curved and sharp.
Pieoe, with bill convex or rounded above and edged on the lower part; legs short and robust, but with smooth toes.
An-Seres (Swimmers), with bill smooth, covered with an epidermis, and thickened at its point; feet with palmated toes.
Gralloe, with bill almost cylindrical, thighs half naked, and legs formed for wading.
Galinoe, with bill convex, and the upper mandible arched over the under; feet formed for walking, and the toes rough below.
Passeres, with bill conical and pointed, legs formed for hopping, and toes slender and divided. In ornithology Linnaeus deserves the same credit as in the other departments of zoology, for his excellent determination of genera and his admirable system of binomial nomenclature. - Brisson, in his Omithologia (4to, Paris, 1760), describes about 1,300 species of birds, arranged in 26 orders and 115 genera, whose characters are drawn from the toes and their membranes, the bill, and feathers of the legs; the descriptions are minute and accurate, and illustrated by numerous copperplate engravings. - Latham, in his "General Synopsis of Birds " and "Supplements" (1781-1801), in his Index Ornitho-logicus (1790), and in his "History" (10 vols. 4to, Winchester, 1821-4), was the next writer of importance on general ornithology. In the last work he divides land birds into orders: I., rapacious or accipitrine, with 4 genera and 363 species; II., pies (like the shrikes, crows, parrots, cuckoos, woodpeckers, and kingfishers), with 32 genera and 1,320 species; III., passerine (finches, swallows, thrushes, and flycatchers), with 17 genera and 1,444 species; IV., columbine or pigeons, with a single genus and 136 species; V., gallinaceous (turkeys, pheasants, grouse, bustards), with 12 genera and 210 species; VI., struthious (dodo, emu, and ostrich), with 4 genera and 8 species.
He divides the water birds into orders: VII., waders, with cloven feet (herons, snipe, sandpiper), with 20 genera and 455 species; VIII., with pennated feet (coots and grebes), with 4 genera and 29 species; and IX., web-footed (flamingo, albatross, gull, duck, penguin), with 17 genera and 359 species. He thus makes in all 111 genera and 4,324 species, of which many are ill determined and improperly made. - Lacépède in 1799 (Histoire naturelle) divided birds into two subclasses. Subclass I. (having the legs feathered, and no toes completely united by wide membranes) contains divisions: 1, with two toes in front and two behind, large and strong, the climbers (grimpeurs), with 6 orders and 12 genera; and 2, having three toes in front and one or none behind, with the 1st subdivision of birds of prey, with strong and curved claws, embracing a single order and 10 genera; 2d subdivision, having the external toes free or united only along the 1st phalanx (passereaux), with 8 orders and 36 genera; 3d subdivision, having the external toes united for almost the whole length (platypodes), like the hornbill, kingfisher, and bee-eater, with 5 orders and 7 genera; 4th subdivision, having the anterior toes united at the base by membrane (galli-naces), with a single order and 12 genera.
Subclass II. (the legs without feathers, or with many toes united by a wide membrane) contains division 1, with three toes in front and one or none behind, with 1st subdivision, having the anterior toes united by membrane (water birds, ducks, &c), embracing 6 orders and 17 genera; 2d subdivision, with all four toes united by a wide membrane (oiseaux (d'eaula-tiremes), like the cormorant and pelican, haying 3 orders and 6 genera; and 3d subdivision, having the toes united at base by membrane (shore birds), with 7 orders and 26 genera; and division 2, with two, three, or four very strong toes, not united at base by membrane (cursores), like ostrich and dodo, with 2 orders and 4 genera: in all, 39 orders and 130 genera. Meyer and Wolff (Almanack des oiseaux de l'Al-lemagne), in 1810, made the 11 orders of rapaces, coraccs, pici, alcyones, oscines, chelidones, columboe, gallinoe, cursores, grallce, and natch tores; this seems to be the first work in which the terms oscines, alcyones, and chelidones are applied to the orders of birds, llliger (Pro-dromus Systematis Mammalium et Avium, 1811) gives the 7 orders scansores, ambulatores (including the 2d, 4th, 5th, and 6th orders of Meyer), raptatores, rasores (including gallinaceous birds and pigeons), cursores (ostrich, bustard, plover), grallatorcs, and na-tatorcs, with 41 families and 147 genera. - Cuvier (Règne animal, 1817) preserved the 6 orders of Linnaeus, founded on the characters of the beak and feet, except that he substituted the previously used term of scansores for those of the pieoe which have two toes before and two behind, placing the remainder among the passeres.
His orders are: I., accijritres, divided into diurnal (hawks, etc.) and nocturnal (owls); II., passeres, divided into tribes denti-rostres (like shrikes), fisirostres (swallows and goatsuckers), conirostres (crows, buntings, and starlings), tenuirostres (humming birds), and syndactyli (kingfishers); III., scansores or climbers (woodpeckers and parrots); IV., gallinoe, or birds resembling the domestic cock; V., grallce or waders, divided into brcvipennes (ostrich), pressirostres (bustards), cultirostres (cranes), longirostres (ibis, curlew, snipe), and macro-dactyli (rail, jacana); VI., palmipedes, divided into bracliypteri (penguins and grebes), longi-pennes (terns and petrels), totipalmes (pelicans), and lamellirostrcs (ducks). - Vieillot in 1817, and in the article Ornithologie of the Nourcau dictionnaire d'histoire naturelle, made 5 orders: I., accipitres, diurnal and nocturnal, with 4 families; II., sylvicoloe, with 2 tribes, zygodactyli and anisodactyli, equivalent to the climbing and passerine birds of other authors, with 30 families; III., gallinoe with families nudipedes and plumipcdcs; IV., grallatorcs, with the tribes di-tridactyli and tetradactyli, with 15 families; and V., natatorcs, with the tribes telcopodes, atelcopodes, and ptilopteri, with 7 families. - Temminck (Manuel d'ornithologie, 2d ed., Paris, 1820-'40) modified the systems of Meyer, Illiger, and Latham, and made 16 orders, comprising 202 genera.
His orders are: I., rapaces or birds of prey; II., omnirorcs (crows, rollers, starlings); III., in-sectivores (thrushes, shrikes, flycatchers, warblers); IV., granirorcs (larks, bunting, finches); V., zygodactyli (cuckoos, toucans, parrots, woodpeckers); VI., anisodactyli (creepers and hummingbirds); VII.; alcyones (bee-eaters and kingfishers); VIII., chelidones (swallows and goatsuckers); IX., columboe or pigeons; X., gallinoe; XL, alcctorides (agami); XII., cursores (ostrich and bustard); XIII., grallatorcs or waders; XIV., pinnatipedes (coots and grebes); XV., palmipedes, swimmers; XVI., inertes (apteryx and dodo). This is followed by Naumann in his Vögel Deutschlands (13 vols. 8vo, Leipsic, 1822-52), and is adopted in Stark's "Elements of Natural History" (Edinburgh, 1828). - De Blainville (1822) called birds pennifera, and made the 9 orders of pre-hensores (parrots), raptatores, scansores, salta-tores (passeres), sponsores (pigeons), gradatores (gallinoe), cursores, grallatores, and natatores.
Besides this system, founded on the characters of the legs and feet, he proposed another, developed by L'Herminier in 1827, based on the anatomical peculiarities of the sternum or breast bone. (See Annates de la sociéte lin-neenne de Paris, vol. vi.) He makes two subclasses: I., normal birds, in which the sternum is provided with a crest, and with the three bones in the shoulder distinct and simply in contact, including 34 families of ordinary birds, from the hawks to the penguins; II., abnormal birds, in which the sternum is formed of two pieces, originally separated, united on the median line into a single plate, of various forms, but always without bony crest or keel; the shoulder bones, distinct in the young, are consolidated in the adult; this includes the single family of curso-res (ostriches). Lesson (Manuel d'ornithologie, Paris, 1828), though in his text he adopts the system of Olivier, gives another in his introduction, as follows: Section L, terrestrial birds, with the orders: 1, insessores; 2, passerini; 3, rapaces; 4, rasores; and 5, heterosoma (ostriches). Section II., aquatic birds, with the orders: 6, grallatores; 7, pinnatipedes; 8, natatores; and 9, paradoxaux (including the genus ornitho-rht/nchus, now universally recognized as a mammal). Gray ("Genera of Birds," 3 vols. 4to, London, 1837-'49) makes the system of Cuvier the basis of his classification, but separates the columbce as an order from the gallince, and the struthiones from the gralloe, forming 8 orders with 49 families. - The famous quinary system of classification was for many years in vogue in England, and exerted considerable influence upon ornithology by calling attention to many affinities and analogies previously overlooked.
Macleay, its founder (Horoe Entomologicoe, London, 1819 - '21), assumes that all animals of a group must be analogous to those of every other group, besides forming a circle in themselves; and he therefore arrays them in circles and groups so as to bring out external analogies, without much regard to structural affinity. Vigors ("Transactions of the Linnaean Society of London,1' vol. xiv., 1825), following out his quincuncial and circular arrangement of affinities, adopts the five orders of raptores, insessores, rasores, grallatores, and natatores, characterized respectively by their feet adapted for tearing, perching, scratching, wading, and swimming. These live groups, which he arranges as circles, are connected as follows: the raptores to the insessores by the owls of the former and the goatsuckers of the latter, the immediate passage being made by the Australian genus podargus (Cuv.); the pigeons are intermediate between the perching and gallinaceous birds, but belong essentially to the latter, and these orders come nearest together at the insessorial plantain-eaters and the rasorial curassows; the passage from the gallinaceous birds to the waders seems to be between the bustards of the former and the genera oedicne-mns (Cuv.) and psophia (Linn.) of the latter; the passage from the waders to the swimmers is by the coot (fulica, Linn.) of the former and the Australian goose (cereopsis, Lath.) of the latter; the swimmers are brought back to the raptores by the frigate bird (tacliypetes, Vieill.) of the former, and probably some of the gypo-geranidm of the latter.
The affinities are thus represented (op. cit., p. 509):
Each of these five tribes in each of the five orders is capable of being subdivided into five families, which may be arranged in circles similarly connected. Swainson (Lardner's "Cabinet Cyclopaedia," vol. xiii., 1837) adopts the same five orders and the general quinary arrangement, and expresses the analogies existing between birds and mammals in the following tabular form:
Carnivorous; retractile claws.
Feeding and living in the water.
Jaws much prolonged.
Domestic; feet lor walking.
He connects the 1st and 2d, 3d and 4th, and 4th and 5th orders by the same tribes as does Vigors; but he is inclined to connect the 2d with the 3d by the dididoe (dodo), which he places erroneously near the vultures, instead of the gypogeranidce, which he considers either the grallatorial or possibly the rasorial type of the raptores; he connects the 5th with the 1st by the megapodidoe instead of the curassows. According to the principle of these systems, birds are connected on the one hand with reptiles through the pterodactyl, and on the other with mammals through the ornithorhynchus and the ostrich. Though these affinities cannot be made the basis of a natural classification, they are interesting, ingenious, and to some extent philosophical. - Oken, in various works from 1809 to 1843, published his system of classification, in which birds are called ear animals, in the division according to the senses, because in them for the first time the external auditory meatus as well as the cochlea is exhibited in perfection; birds are also nerve animals, in the anatomical division, as they have a complete nervous system with cerebrum and cerebellum. They belong to his 2d province, of sarcozoa, 4th circle or flesh animals, and 12th class or otozoa or neurozoa.
They are the first encephalic animals, as the brain defines the head, which is here for the first time freed from the trunk and placed upon a long neck far removed from the thorax, hence also called cervical animals; the caudal vertebrae, on the contrary, are fewer than in other classes. Birds are capable of instruction, affection, imitation, gratitude, and other mental manifestations not seen in reptiles and fishes. They are the closest repetition of insects, the thorax predominating over the rest of the body, with large respiratory muscles; their lungs are a cluster of insect trachea), full of foramina through which air penetrates all over the body, as in insects; the intestine lies in the air, and the bird to a certain extent breathes from it; the whole bird is lung, and its body a thoracic cavity, as the latter is a sexual cavity in the fish and an abdominal cavity in the reptile; the food is crushed in a muscular stomach, as in insects; a bird is an insect with fleshy limbs, and a feather is an insect's wing.
With the bird, for the first time, the voice proper breaks forth; "the bird speaketh the language of nature." In Oken's " Physiophilosophy" (Kay society edition, London, 1847) are given two great divisions of birds, according as the young require to be fed by the parents or not, the former being the lowest; this principle of division, first published in 1821, has retained its place in ornithological science, and lies at the base of the systems now generally followed in Europe and in this country. - Carus (1828), in his Grund-riss der verghichenden Atiatomie, ranks birds in his 6th class or ccphalo-thoracozoa, characterized by great development of the respiratory organs. He makes the orders: L, natantes, having relations with reptiles, especially such of its members as fly poorly or not at all (like the penguins); II., vadentes or waders; III., prendentes, with the suborders rapaces, pas-seres, scansores, and gallinm; and IV., incedentes or struthious birds, having relations to mammals. Ehrenberg (1836) ranks birds as the second and last class of the nutrientia or animals which take care of their young; this division is not strictly natural, as some reptiles and fishes have a care for their progeny. - The eggs of birds have generally been selected for investigations of embryology.
The unity of anatomical structure in all vertebrates is confirmed by the common structure of the primitive egg, and the order of classification from anatomical evidence by the metamorphoses which each class undergoes to its full development. The bird goes through its fish-like and reptilian structure and form; the only difference between the egg of a bird and a mammalian ovum, as to external covering, is that the former has a hard shell when laid protecting the immature chick, while in the latter the envelopes remain membranous, having a peculiar connection with the maternal body which is not severed until the birth of the young. Von Baer (1828) places birds in his double symmetrical type, whoso embryos acquire an allantois, but have no umbilical cord, having wings and air sacs. Van Beneden (1855) ranks birds as the second class of his hypocotyledoncs or hypovitellians, in which the vitellus enters the body from the ventral side. Prof. Agassiz ("Lecture on Embryology," Boston, 1849) gives the results of some observations on the structure of the bird embryo, from which it appears that the limbs are not at first developed in the form which is to be permanent; the legs and wings are formed as fins; in all the orders of birds, with their various powers of locomotion, the legs and wings are uniformly webbed like the fins of fishes; in the same manner the primary condition of the heart, lungs, and other organs of a bird is that of these organs in a fish.
This would indicate that the web-footed birds are lower in the scale than those with divided toes; and that the union of all the former into one group, however different the structure of their wings, plumage, and internal organs, and their mode of life - the almost wingless penguin with the swift-flying ocean birds, the hook-beaked predaceous gulls with the flat-billed and timorous ducks - must be an unnatural arrangement. The examination of the feet of an embryo robin, swallow, warbler, and finch, showed all four toes directed forward and webbed, while in the mature birds they are separate, three directed forward and one backward; he found the bill of the immature robin resembling that of a vulturine bird, indicating the comparatively low type of the latter; indeed some water birds, like lestris (skua gull), have a bill very greatly resembling that of the vultures; some birds of prey also resemble water birds in the rudiment of a web between the toes. He regards birds which have ail their toes directed forward as of a lower type than those in which one is directed backward, as, for instance, the pelicans and cormorants among water birds, and the swifts (genus cyptelus, 111.) among swallows; a similar idea was broached by Sundevall in 1835. In Prof. Agassiz's classification ("Contributions to the Natural History of the United States," vol. i., Boston, 1857), birds form the seventh class of vertebrates, with four orders, natatores, gralloe, rasorcs, and insessores (including scansores and accipitres). - The principle of classification of birds according as the young are or are not fed by the parents, proposed by Oken, was adopted by Sundevall (KongliJc Vetenskaps-Academiens Handlingar, Stockholm, for years 1835 and 1843), who also used the position of the hind toe and the powers of song in his classitication.
His sections are: A. Aves altrices, which nourish their young in the nest, having either the thumb or the external toe turned back and entirely resting on the ground. These comprise the divisions or legions:
Volucres (Passeres Of Cuvier), typical flying birds, with the thumb only turned back, containing the passeres and oscines (singers).
Gressores Or Walkers, containing the swallows and humming birds, woodpeckers, parrots, cuckoos, kingfishers, owls, hawks, guans, and pigeons. B. Aves proecoces, whose young seek their own food soon after birth, having the thumb elevated or absent.
Cursored, runners, the pheasants and grouse, the ostrich family, bustards, herons, storks, rails, and sandpipers.
Nata-Tores Or Swimmers, with the femur and base of tibia included under skin of abdomen, including the gulls and petrels, pelicans and gan-nets, ducks, loons, guillemots, and penguins. Keyserling and Blasius (Wirbelthiere Euro-pas, Brunswick, 1840) make the six orders rapaces, scansores, oscines, gallinaceoe, gralla-tores, and natatores. - Though Cuvier long before had drawn attention to the peculiar muscular apparatus of the larynx in true singing birds, and to its inferior development or absence in others, J. Miiller (Berlin " Transactions," 1845) first laid stress on its importance as an element in classification; and on this and on corresponding external characters, Cabanis, and after him Burmeister (Thieve Brasiliens, Vogel, Berlin, 185G), divided the insessores into strisores, clamatores, and oscines. According to Cabanis, the fusion of all the scutellae of the tarsus into a continuous envelope or " boot," without indication of divisions, is the type of the highest bird, and the position of the families and genera in the scale is high according to their approach to it and to the reduction in size of the first quill.
Cabanis (Archiv far Naturgescliichte, Berlin, 1847) makes the ten orders of oscines, clamatores (prying birds, like shrikes, rollers, and kingfishers), strisores (having no power of modulating the voice, like swallows and goatsuckers), scansores, coluniboe, raptatores, rasores, cursores, grallatores, natatores; the first four orders compose a subclass named insessores by Bonaparte in his catalogue of 1842. Prince C. L. Bonaparte (Gomptes rendus, Oct. 31, 1853) constructed a table in which the two great subclasses, altrices and pnecoces, are made with reference to whether the young require to be fed by the parents. Van der Iloeven ("Handbook of Zoology," English translation, 1857) makes the following six orders: natatores, grallatores, gallina, scansores or zygodactyly passerini (ambulatores of Illiger and aniso-dactyli of Vieillot), and raptatores. Prof. F. S. Baird (" Pacific Railroad Survey," vol. ix., Washington, 1858) adopts a classification chiefly from Keyserling and Blasius, Cabanis, Bonaparte, and Burmeister. Prof. Richard Owen ("Anatomy of Vertebrates," vols. i. and ii., London, 1866) retains with slight modification the orders as adopted by Gray, with the exception of columboe, which he reunites with rasores, and passeres, which he separates into two distinct orders, the rolitores (swifts, goatsuckers, bee-eaters, humming birds, kingfishers) and cantores (flycatchers, warblers, thrushes, finches, crows, swallows, creepers). The raptores, scansores, volitores, and cantores constitute his first section, the altrices, while the remaining orders, rasores, cursorcs, grallatores, and natatores, are included in the second section, the prmcoces.
A third section, the uroioni, is added, of which the extinct arclmopteryx forms the type. The classification of Prof. Huxley, as put forth in his " Classification of Animals " (London, 1869) and "Anatomy of Vertebrated Animals" (1871), departs widely from any of the foregoing, and will probably meet with but little favor among present ornithologists. It is founded mainly upon the characters of the sternum (as in the classification of De Blainville) and vomer, circumstances which scarcely appear of sufficient significance to serve as a basis in a natural classification. Huxley divides birds into three primary groups, the saururoe, ratitm, and carinatm, the first of which corresponds with the uroioni of Owen. The ratitw and carinatoe are respectively characterized by the absence and presence of a keel, the former comprising the kiwis, moas, cassowaries, and ostriches. The carinatai are further subdivided into four secondary groups, founded upon the relative position and structure of the bones entering into the formation of the palate, which are in turn resolved into 20 alliances, to each of which the termination morphea is appended; e. g., geranomorphai, the cranes, and coracomorphm, the passerines.
The arrangement is as follows: I., drommognathm, with one alliance (the tinamous); II., scliizognaihm, with nine alliances (the plovers, gulls, penguins, cranes, hemipods, fowls, sand grouse, pigeons, and hoazins); III., oegithognathoe, with three alliances, the passerines, swifts, and woodpeckers; IV., desmognatlm, with seven alliances (birds of prey, parrots, coccygomorphoe, including the cuckoos, kingfishers, and trogons, the anserine birds, flamingoes, storks, and cormorants). - No department of zoology has been so extensively and elegantly illustrated as that of ornithology; reference may be made to the figures in the works of Sloane, Catesby, Seba, Edwards, Albinus, Brisson, Sepp, Browne, Latham, Pennant, Hardwicke, Bewick, Donovan, Lewin, Shaw, Jardine and Selby, Buffon, Desmarest, Lo Vaillant, Temminck, Spix, Vieillot, Riip-pel, Audebert, Horsfield, Lesson, Swainson, Gray, Gould; and in America to those of Wilson, Bonaparte, Audubon, De Kay, Cassin, Baird, and Brewer; to the " Proceedings of the Zoological Society" of London (descriptions of Mr. Sclater and others), and the various illustrated works, the results of the national expeditions sent out by England, France, the United States, Russia, Holland, etc Among the magnificent works may be mentioned the 1,008 planches enluminées of Butfon (fob, Paris, 1770-'86) ; the 600 planclies coloriees of Temminck ; Le Vaillant's birds of Africa, parrots, birds of paradise and rollers, promerops, and rare birds of America and India, in all about 570 plates ; Edwards's 362 plates of uncommon birds ; Vieillot and Audebert's nearly 180 plates of birds of brilliant plumage; Gould's series of the birds of Australia and Europe, the humming birds, trogons, etc.; and Audubon's 435 plates in folio of North American birds.-America has not produced any original system of classification of birds; but the writings of Nuttall, Wilson, Bonaparte, Audubon, De Kay, Baird, Coues, Allen, Brewer, Lawrence, and Cassin have well illustrated the ornithology of this country; many new and beautiful species have been added since 1840; and Messrs. Baird, Brewer, and Ridgway are now (1875) publishing a new work on North American birds. - There are probably 6,000 species of birds, of which about five sixths are known.
Birds existed on the earth before the present geological epoch, but their remains in a fossil condition are comparatively rare. The oldest date claimed for birds is the new red sandstone epoch, where in the Connecticut valley Dr. Hitchcock and others have found tracks which they pronounce those of birds; but many suppose them to have been made by reptiles, and for various reasons it is doubtful if any birds existed at that epoch. Birds with reptilian characters certainly did appeal in the upper oolite (see Archaeopteryx) ; birds of prey have been found in the tertiary and diluvial ; passeres in the same; gallium, rare in the tertiary, are abundant in the diluvium; among cursores, the genus rhea has been found in the caverns of Brazil, and the dinornis, epy-ornis, etc, have been met with in alluvial deposits; the palmipedes are still earlier, and the genus cimoliornis (Owen), coming near the albatross, has been found in the chalk of Europe.