BIRDS IN GENERAL. 



resounds with the challenge of anger, or the 

 call of allurement. This delightful concert 

 of the grove, which is so much admired by 

 man, is no way studied for his amusement : it 

 is usually the call of the male to the female ; 

 his efforts to soothe her during the times of 



placed, is lighter than the opposite side; so that in 

 whatever position the egg is placed, the same part is 

 always opposed to the belly of the incubating bird. The 

 first trace of the chick is not perceptible until some time 

 after the commencement of incubation; in the hen's 

 egg, for instance, scarcely before the end of the first 

 day j and at the end of the second, the remarkable spec- 

 tacle of the first motions of the incomplete heart 

 (punctum saliens) presents itself. At the end of the 

 fifth day, the whole jelly-like creature may be seen to 

 move. On the fourteenth, the feathers appear ; at the 

 commencement of the fifteenth the chick attempts to 

 breathe ; and on the nineteenth it is able to chirp. 



The first form which the bird assumes in the egg 

 differs more from that which it possesses after being 

 hatched, than mammifera do in their first and subsequent 

 form ; we might say that the chick in the egg arrives at 

 its more perfect form by a real metamorphosis, and this 

 as well with respect to individual organs, (the heart for 

 example,) as the whole form. 



Among the many organs subservient to the remarkable 

 economy of the chick during incubation, the two most 

 important are the vascular membranes, which are most 

 conspicuous and beautiful about the middle of the pro- 

 cess. These are the chorion, which is then expanded 

 under the shell ; and the membrane of the yolk (mem- 

 brana valvulosa vitelli,") which communicates with the 

 intestinal canal of the young animal. The first serves 

 instead of lungs, for the phlogistic process already men- 

 tioned : and the second for nutrition by means of the 

 yolk, which is gradually diluted by mixing with the 

 white. 



Every species of bird has a fixed time of incubation, 

 of different length in different cases, and capable of 

 being accelerated or retarded according to the difference 

 of climate, and the warmth or coldness of the weather. 

 In the common fowl, the chick is usually able to creep 

 out of the shell about the end of the twenty-first day. 



The young birds are fed for some time by the mother 

 with great care ; and among those which live in mono- 

 gamy, also by the father, principally, in the granivorous 

 birds, with the regurgitated contents of the crop, until 

 such time as they are feathered, and capable of provid- 

 ing for themselves. 



Birds, in proportion to their size, and as compared 

 with mammifera, attain a very advanced age : it is 

 known that, even in captivity, eagles and parrots will 

 live more than a hundred, chaffinches and goldfinches 

 more than twenty-four years. 



Birds are extremely important creatures for the eco- 

 nomy of nature in general, although their immediate 

 utility to mankind is infinitely less than that of mammi- 

 fera. Tney destroy innumerable insects, and the 

 thoughtless extirpation of some birds, supposed to be 

 noxious, as sparrows, crows, &c., in many districts, has 

 generally given rise to an infinitely more prejudicial 

 multiplication of vermin. Other birds destroy larger 

 animals, as field mice, snakes, frogs, lizards, or consume 

 carrion. Many extirpate weeds. On the other hand, 

 they assist the increase and propagation of animals, as 

 well as plants. For instance, it is known that wild 

 ducks, in their emigrations, carry impregnated spawn 

 into remote ponds, &c., and thus stock them with fish. 

 Many birds swallow seeds, which are subsequently 

 expelled whole, and thus extensively dispersed, as the 

 doves of Banda with the nutmeg. The excrement of 



VOL. n 



incubation ; or it is a challenge between two 

 males, for the affections of some common fa- 

 vourite. 



It is by this call that birds begin to pair at 

 the approach of spring, and provide for the 

 support of a future progeny. The loudest 



sea-birds manures bare cliffs and coasts, so as to render 

 them capable of producing useful plants. Many species 

 of falcons may be taught for the chace, as well as the 

 cormorant for taking fish. Many birds, together with 

 their eggs, fat, &c., serve for food.; the entire skins of 

 sea-birds for the clothing of many northern nations; the 

 feathers for stuffing beds, for writing, for various and 

 often costly ornaments, in which respect also they form 

 an important article of trade among many savage people, 

 particularly the islanders of the Pacific ocean. 



The injury which birds give rise to, is almost wholly 

 confined to the destruction of useful animals and plants. 

 The condor, the vulture, and other birds of prey, kill 

 calves, goats, sheep, &c. The osprey, and many water- 

 birds, are as injurious to fish and their young, as the 

 hawk, sparrow-hawk, and magpie, to common poultry. 

 Sparrows, and many small singing birds destroy corn, 

 grapes, and fruit. And lastly, they assist in propagat- 

 ing weeds as well as serviceable plants. Among birds, 

 no actually venomous animals are to be found. 



As the general form of birds'is tolerably uniform, and 

 certain parts of their body, as the bill and feet, which 

 are connected with their mode of life, food, &c., influ- 

 ence their total habit very materially, most ornithologists 

 have grounded their classification on the differences of 

 one or other of those parts : Kleine, for instance, on 

 the form of the toes ; Mohring, on the coverings of the 

 legs ; Brisson, on both, in combination with the nature 

 of the bill, &c. Linnaeus, in the plan of his System of 

 Birds, also adopts several parts, in combination with, in 

 general, a reference to the total habit ; although in it 

 practical application, he appears at times to have been 

 forgetful ; at least it is impossible to understand how 

 parrots, humming-birds, and crows, should be placed in 

 the same order ; or why he should have placed doves 

 and the common fowl in two separate ones, with other 

 approximations and divisions of the same nature. 



I have, therefore, allowed myself to make some devia- 

 tions from the Linnean system, and endeavoured to 

 divide the whole class among the following nine orders. 



LAND BIRDS. 



I. ACCIPITRES. Birds of prey ; with strong hooked 

 beaks, mostly with short, strong, knotty feet, and 

 large crooked sharp claws. 



II. LEVIROSTRES. With short feet, and very large, 

 thick, but mostly hollow, and therefore light, 

 bills. Parrots, toucans, &c. 



III. PICI. With short feet ; moderately long and small 



bills, and the tongue sometimes worm-shaped, 

 sometimes thread-like. The wry-neck, wood- 

 pecker, creeper, humming-bird, &c. 



IV. CORACES. With short feet, and the bill moder- 



ately long, tolerably strong, and convex above. 

 Ravens, crows, &c. 



V. PASSERKS. The singing birds, with swallows, &c. 

 The feet short, the bill more or less conical, 

 pointed, and of various length and thickness. 

 VI. GALLING. Birds with short feet, the bill some- 

 what convex above, and having a fleshy mem- 

 brane at the base. I have placed the doves in 

 this order, as they are far more closely connected 

 with the Gallinae than the Passeres, among which 

 Liimteus had placed them. 



VII. STRUTHIONES. Large land birds, unsuited for 

 flying The ostrich, cassowary, and dodo. 



