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THE VOICES OF BIBDS. 131
and autumn, a great variety of species may often be noticed in hedges and bushes, which seem to take a great delight in the utterance of a common cry. Again, when in confinement, birds may often be induced to sing by various noises, loud conversation, and above all, by instrumental music; though on wild birds these means would produce no other effect than to frighten them away.*
"In many cases also different species have a language, which serves for various purposes of mutual communication. For instance, ravens, crows, jackdaws, &c., understand and respond, both by voice and action, to each other's call. By imitating the call of the yellow-hammer, the fowler succeeds in taking the ortolan, the snow-bunting, the reed-bunting, the foolish-bunting, &c.: the cry of the chaffinch decoys the mountain-finch; and that of the siskin attracts the citronfinch and the redpole.
"These notes, if connected in a melodious succession, are called a song; if unconnected, a call. In some cases the call is the same, however different the emotions which it is intended to express: in others, it is very various. For instance, the chaffinch's call, when on the wing, is eyak! eyak! its expression of joy is fink ! fink.'—if angry, the same syllable is repeated more quickly; and trief! trief! is the sign of tenderness or melancholy. The raven's call— graab! graab !—is, on the contrary, the same under all circumstances; and the only indication of a change of emotion, is the degree of rapidity with which it is uttered.
* A singular instance of the effect of musical sounds fell under our observation, some few years ago, in the case of a favourite canary of our own. An Eolian harp had been placed in the casement of the room in which the bird was hanging, and scarcely had the wind swept over the strings, calling forth the mournful, sighing tones of the little instrument, than the poor canary, as though seized with a sudden insanity, flew wildly against the bars of its cage, striking both head and wings against them. The harp was removed; but the memory of the mournful tones seemed still to vibrate through the nerves of the wretched little bird. It continued several days in a most agitated state; and at length having loosened a wire in the cage, made its escape, and flew away through an open window. The fate of this canary was long a matter of speculation in the family, but was nearly forgotten when another little incident occurred which singularly recalled it.
My two youngest children discovered one day in the garden a young turtledove, which seemed much exhausted and half-famished. It sat listlessly upon a bough, and allowed the children to catch it; its poor little feet were bleeding, and altogether it was in a most miserable condition, as though it had been deserted by its companions on one of their mysterious migrations. The children tended it with the greatest possible love and care, and gradually it recovered its health and spirits. It naturally became a great favourite, and one day was carried by them into the room where they were taking their music-lesson. But before long the dove, like the canary of former years, was seized with a sort of insanity; it beat with its wings, and flew madly about its cage. The children carried it away into a distant room, hung a cloth over its cage, did all they could to soothe it, and then returned to their lesson. When the lesson was over, they hastened to their poor favourite, but it was dead!—Ed.
"What is called the song of birds is, in all cases, expressive either of love or happiness. Thus, the nightingale sings only during the pairing season, and the period of incubation, and is silent as soon as compelled to feed its young; while, on the contrary, the starling, the bullfinch, and the canary, sing throughout the year, except when dejected by moulting. It seems, in general, to be a prerogative of the males, by which they either invite or seek to retain the affections of the females. There are indeed a few species, e. g. the redbreast, lark, canary, &c, the females of which, especially if kept by themselves, manifest the capability of uttering a few notes like those of the male; but in general they only listen to the song of the males, in order to show their preference for the most accomplished singer. In a cage of canaries, the liveliest female always pairs with the best singer; and a female chaffinch, when wild, will choose out of a hundred males, the mate whose song is most pleasing to her."
Here are some interesting remarks from the same author regarding
The Plumage or Birds.
"The feathers of birds, the coverings of the featherless parts, and even the beaks and claws, are all, chemically speaking, formed of nearly the same materials; and nearly the same with the hair and cuticle of all animals, and even with the epidermis which covers living shells. This material is coagulated albumen, or nearly the same substance as white of egg when consolidated by heat, in which state it better resists the action of water than almost any other flexible substance. This substance is, especially in the upper or more coloured and glossy part of the feathers, combined
FEATHERS OF WATER-BIIIDS.
with oils and metallic substances in very minute portions; but in the down and the light-coloured feathers it is nearly pure.
"The under part of the clothing feathers, and also a small portion of almost all feathers near the tube or barrel, consists of down, but the exposed surfaces, even of the softest feathers, are smoothed so as to throw off the water. This
is the case even in those water-birds which pass the greater part of their time with the under part of their body immersed in water. On them, the down is abundant in proportion as the habits of the birds expose them to cold; and the external surface is waterproof, from its glossy texture, and (possibly ?) also from the oil with which the bird anoints it by means of its bill: but in all birds there is an external surface, adapted to prevent decomposition, and an inner downy matter, as a protection against the changes of temperature. The down is partly on the rootends of the feathers, and partly on the skin in the intervals between them, but the material is in all cases substantially the same; the difference is in the form, or in the colour, which generally approaches nearer to white in the down than in the feathers. When the bird remains all the year round in situations where there are great differences in the heat of the seasons, the down increases in quantity during winter; and when birds of a warmer climate are domesticated in a colder one, they become more downy. The form which the down assumes is often characteristic of the habits of the bird. In the ostrich there is none; in some birds it is a mere tuft at the origin of the webs, in others it is a second feather originating there; and there are all the intermediate states in different birds, and very considerable seasonal differences in the same bird.
"Different birds find their food in different states, both of the atmosphere and the waters; and very beautiful corresponding differences in their plumage may be traced. The plumage upon the raven, which braves the storm in the wilds, is very different from that of the gallinaceous or poultry races, which a slight shower drives to their cover or their perch; and ducks and other water birds, which seek their food peaceably on the banks, or by swimming in the shallow waters, have very different plumage from those which hawk about on the wing, in order to catch what the troubled sea brings to the surface. If the habit of the bird be to steal softly on its prey, then the feathers are fined off to exceedingly delicate points, so that it can glide silently through the air.
"The feathers of birds, while they remain perfect and firm in their connection, are really parts of a living animal, and as such they must be regarded as organs of feeling. They do not, probably, in themselves feel pain, but they are in intimate connection with parts which do. The epidermis in no animal appears to feel pain, even in those parts of the animal which are regarded as being more immediately the organs of sensation; but they very speedily transmit impressions to the parts that do feel. It is the same with hair, and with all the appendages of the cuticle, such as nails, claws, hoofs, and horns. The horse feels his footsteps in the dark, even when his hoofs are shod with iron; and he SENSE OF FEELING IN FEATHEBS. 135
feels not only the touch of a wall, a gate, or any other obstacle, but he feels the difference which such objects cause in the resistance of the air, and that enables him to avoid touching them.
"The horse feels his way by means of the hair, and birds must in like manner often feel their way by their feathers. Such must be habitually the case with owls and other nocturnal birds, which can fly darkling through thick woods and other intricate places; and though the owls have their eyes directed forwards, and not laterally, as many other birds have, they are by that means less capacitated for avoiding by sight, even admitting that they can see with the smallest possible portion of light, those obstacles which it would be the most awkward to encounter—those of course which would injure, entangle, or impede their wings. If one wing were to come in contact with a tree, or even with a leaf, the bird would be upset, as certainly as a man is, when in walking heedlessly he places one foot over a pit or ditch while the other is on the ground.
"The necessity of feeling with the feathers is not confined to nocturnal birds, but is essential to the safety of all the winged tribes, the feathers must therefore always be in a state of great perfection. Now though the shafts of many feathers and the larger ribs of the webs or bones of not a few, are of considerable substance and strength, all feathers are subdivided till the ultimate ramifications are exceedingly minute. Consequently, they produce very large surfaces to the air, in proportion to the quantities of matter they contain.
"Feathers are thus very much exposed to atmospheric action, which dries them, and renders them unfit for the functions that are required of them. They are also apt to be broken or torn in the flights, the wars, and the labours of their owners. They are therefore periodically shed and reproduced; and the reproduction usually takes place in such a way, so that the bird shall be in best feather at the very time when it has the greatest labour to perform.
"The resident native birds of countries where the heat of the year is comparatively uniform, moult gradually, and the same may be said of those that have their haunts in regions that are always cold, and where the food is comparatively