ORNITHOLOGY. 



351 



fear, the dread of imminent danger, desire for society, 

 or longing for his mate, love, melancholy, &c., are 

 expressed by a variety of notes, which make a lan- 

 guage intelligible not only to birds of the same 

 species, but often to the other tribes. When one 

 of the songsters of the wood perceives a bird 

 of prey, the whole forest grows silent at his 

 warning voice. Birds are spread over the .whole 

 earth ; a few species extend even from the polar 

 circles to the tropics : their places of abode are 

 suited to their wants and peculiarities, and embrace 

 rocks and dens, trees and shrubs, earth and water. 

 Whilst wood-peckers and parrots pass all their time 

 upon trees, partridges, quails, &c., remain on the 

 ground ; storks and herons visit the marshes ; 

 swans and water-fowl live in rivers and ponds. 

 Birds are in general, very long-lived, although their 

 growth is rapid, and their period of procreation very 

 early. In quadrupeds, the duration of life usually bears 

 a certain proportion to the period at which they attain 

 their full powers ; but it is very different with birds. 

 A cock arrives at maturity in a year, and yet has 

 been known to live upwards of twenty years ; a linnet 

 fourteen ; parrots forty ; and eagles a hundred years. 

 From this longevity of birds, it is probable that they 

 are subject to few diseases. The only one which is 

 universal to them, if it can be termed a disease, is 

 moulting, or the operation of changing their plumage, 

 during the continuance of which, they are sickly and 

 disordered, and many die. This process, which oc- 

 curs every year, appears to be performed in the fol- 

 lowing manner: When the feathers have attained 

 their full size, the pen part; nearest the bird, grows 

 harder, and shrinks in its diameter, thus gradually 

 compressing, and finally obliterating the vessels 

 which supply it with nourishment, and thus becomes 

 an extraneous body, which is at last loosened in its 

 socket, and falls off. Whilst these changes are tak- 

 ing place, the rudiments of the new feather are form- 

 ing beneath, which rapidly attains its natural size, 

 after it has been protruded through the skin. This 

 process, it will be seen, is very analogous to the an- 

 nual shedding of the horns in the deer tribe. (See 

 Deer.) Most birds pair at certain seasons, and con- 

 tinue this conjugal union whilst the united efforts of 

 both are necessary in the formation of their tem- 

 porary habitations, and in the rearing and main- 

 tenance of their offspring. Some birds, however, 

 especially among those of prey, continue their attach- 

 ment to each other for a much longer period ; some- 

 times even for life. In general, birds are more pro- 

 lific than quadrupeds, and their productiveness is 

 visibly increased by domestication. There is a re- 

 markable circumstance connected with this subject, 

 and which is peculiar to the feathered race a bird, 

 when she has produced her usual number of eggs, 

 ceases, in ordinary cases, to lay. If, however, by 

 any accident, these eggs are destroyed, she will again 

 lay the same number. This is strongly marked in 

 the common hen, who, if her eggs are constantly 

 taken away, does not begin to hatch, but goes on 

 producing eggs to an almost indefinite extent. The 

 ovation of birds is considered as an important part 

 of their history, and is closely attended to by writers 

 on ornithology. Almost all birds incubate, or hatch 

 their eggs, by keeping them at a uniform tempera- 

 ture by brooding over them. The ostrich and casso- 

 wary, however, do not perform this maternal duty, 

 merely depositing their eggs in the sand, and leaving 

 them to be hatched by the heat of the sun. (For 

 the process of incubation, see Incubation') Before 

 laying, all other birds are directed by instinct to the 

 operation of building a nest or habitation for their 

 young. The nidification of birds has deservedly 

 been a subject of much admiration ; for they con- 



struct these temporary habitations with such exqui- 

 site skill as to exceed the utmost exertion of human 

 ingenuity to imitate them. Their mode of building, 

 the materials employed, and the situations selected, 

 are as various as the different kinds of birds, and yet 

 are all admirably adapted to their several wants and 

 necessities. They conceal them carefully from the 

 eyes of rapacious animals and of men, and their cau- 

 tion is greater in proportion to the dangers by which 

 they are surrounded. The materials are carefully 

 selected, and are generally united with great art. 

 In the larger number of species, the female is the 

 principal builder, whilst the male^carries the materials. 

 To give a detailed account of the construction of 

 nests, would swell this article beyond all due bounds. 

 Those who wish for full information on this interest- 

 ing subject, will find it pleasingly and elaborately 

 detailed in Rennie's Architecture of Birds. When 

 the building is finished, the female lays her eggs : 

 several water-birds lay but one, birds of prey two, 

 crows and ravens four, the titmouse from eight to 

 twelve, domestic hens forty to. fifty. The eggs dif- 

 fer in size, form, colour, &c., according to the pecu- 

 liarities of each species. After the warmth of the 

 brooding female (in many species the male assists 

 the female in this business) lias developed and ma- 

 tured the germ in the egg, the young breakout of the 

 shells, and the love, tenderness, and care now shown 

 by the parents are admirable. The mother warms 

 the naked brood under her wings, whilst the father 

 brings the choicest food. The feeble swallow defends 

 herself and her young ones, or dies together with 

 them ; the domestic hen runs along the pond with 

 cries of anguish when the young ducks which she 

 has hatched, have been carried by their instinct into 

 the water. When the young are produced, the next 

 object of parental care is their protection and sup- 

 port ; and these duties are fulfilled with astonishing 

 spirit and industry. The most timid become coura- 

 geous in defence of their progeny, and willingly ex- 

 pose themselves to danger to shield their tender and 

 helpless offspring. The young of those birds who 

 build on the ground are generally able to run soon 

 after they are excluded from the shell, and the 

 mother's care is confined to leading them to their 

 food, and teaching them how to collect it. It is far 

 different with those hatched upon trees ; they remain 

 in the nest for a long time, during which both parents 

 are sedulously employed in providing them with 

 a regular supply of food. When their plumage is 

 fully grown, they are gradually taught to fly, and, 

 qualified to provide for themselves, the parents for- 

 sake them, as no longer needing their care. Birds, 

 although the most marked of all the classes of ani- 

 mals, resemble each other so closely in their specific 

 characters, that their subdivision is extremely difficult. 

 Like the mammalia, their distribution into orders is 

 founded on the organs of manducation and those of 

 prehension. From the difference of these organs, 

 naturalists have arranged birds in various orders. 

 The following is that adopted by Cuvier in the last 

 edition of his Animal Kingdom : 1. BIRDS OF PREY 

 (accipitres, Lin.) ; distinguished by their crooked 

 beak and claws, by means of which they are enabled 

 to overcome and prey upon other birds, and even the 

 weaker quadrupeds. They hold the same rank 

 among birds as the carnivora among quadrupeds. 

 They all have four toes, and the nails of the great 

 and middle toes are the strongest. They form two 

 families, the DIURNAL and NOCTURNAL : the first 

 having nostrils inserted in a naked cere, three toes 

 before and one behind, without feathers ; eyes directed 

 sideways : the second having nostrils at the anterior 

 edge of the cere, which is more or less covered with 

 stiff hairs ; the external toe capable of being turned 



