Puslapio vaizdai
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tends to become obliterated, owing to the manner in which the bird lets itself down upon the eggs. It treads carefully among them, arranges its feet at the proper distance apart, then sinks back until its tarsi lie horizontally on the ground. This brings the bulk of the body outside a section of the ridge, and in working itself in so as to cover the clutch of eggs, the bird drags the sand, of which the ridge is formed, in with it. However, the ridge is rebuilt in a curious manner. The sitting bird, if excited in any way, especially if alarmed, pecks at the sand outside the nest and, lifting it in beakfuls, deposits it on the raised margin.

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Mr. Cronwright-Schreiner, probably the best authority regarding ostriches in a state of domestication, considers that monogamy is normal among these birds, and that such is the only condition quite favorable in the matter of the hatching out of the young. The subject is an interesting one, the evidence in favor of both monogamy and polygamy being very strong. My own experiences among wild birds led me to conclude that the usual breeding family consisted of a cock and two hens. Mr. Schreiner's main points are, (1) that a pair make the nest, and (2) that the best results ensue when there is only one hen. The circumstance of the pair making the nest is not, it is submitted, of any particular significance. The South African Bantu are a polygamous people, but no Bantu will marry more than one wife on one occasion. That the best results in the matter of incubation are found in monogamy is undoubted.

It may be that the ostrich is polygamous against his will, but in his natural condition his polygamy — or at least bigamy is hardly to be doubted. The original numerical proportion of the sexes is about equal, but

the males fight and kill one another after the manner of men; consequently there is a certain number of redundant females. When several of these attach themselves to an already married male, the consequences are apt to be disas

trous.

When a nest contains too many eggs, the latter cannot all be covered by the sitting bird. About twenty is the number giving the best results. Instances have been recorded of as many as a hundred and fifty eggs lying in and around a single nest. In such a case, not a single chick would be hatched out. However, the question as to whether the ostrich has been born polygamous, has achieved polygamy, or has had polygamy thrust upon him, must for the present remain unsettled.

The cock sits on the eggs from about four o'clock in the afternoon until about eight next morning. Although he sits for approximately sixteen hours to the hen's eight, the actual trouble incidental to hatching is more or less evenly apportioned between the two. About eight hours of the cock's sojourn are spent in sleep. He has an unbroken eight-hour period wherein to feed. The hen, on the other hand, has two fourhour periods. In feeding the birds stroll leisurely along, cropping suitable herbage on their course. In leaving the nest or returning thereto, the wild bird never takes a straight course. The motive underlying this is obvious.

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At the end of about six weeks the chicks will have hatched out. At first they are weak, utterly helpless creatures, with strange swellings on head, neck, and foot. However, within a few days they become active and, on the approach of danger, will scatter and take cover quite skillfully. They are a dull yellowish brown in color, with

irregular longitudinal stripes of darker brown on the neck. The body covering is of down, interspersed with thick, short feathers with pointed tips. These suggest minute porcupine quills. Before eating food the chicks pick up small stones wherewith to furnish their gizzards. During the later stages of incubation probably owing to want of exercise the parent birds become constipated; their excrement is emitted in small, hard lumps. This forms the first food of the chicks. The latter do not all emerge from the shells on the same day; it usually takes about four days for the whole brood to appear.

After the first chicks have advanced from their stage of helpless bewilderment and are able to move about, the cock-bird leads them for short excursions in the vicinity of the nest, where they begin to peck feebly at whatever herbage exists. It is not unusual to see the cock leading five or six chicks afield, while another five or six lie or crouch stupidly on the raised margin of the nest, and yet another five or six are cheeping within the yet unbroken prison of the shell. There is considerable difference of opinion on the point as to whether one of the parent birds breaks the shells to free chicks whose emergence is unduly delayed. My own strong opinion is to the effect that the wild hen does so, by carefully pressing the eggs with the sternum plate. During the final period of hatching, both male and female-especially the latterbetray great excitement, and will fiercely attack any animal which happens to come near. The cry of the chick is pitched in a high key. When the chick is very young the note is tremulous; it is always liquid and plaintive.

The observation of wild birds engaged in the process of hatching is one of the most difficult operations a naturalist can undertake. It is possible to

observe successfully only by locating the nest by day, and afterwards approaching it before dawn. Even this course is only occasionally successful. The level desert rarely contains any landmarks recognizable in the dark, so

- unless one be accompanied by a Bushman guide, and Bushmen nowadays are scarce there is considerable danger of missing the located spot. Moreover, there is always the chance of disturbing one or other of the hens resting in the darkness, and her flight may cause the cock to rise from the nest and decamp. However, let us assume success, and that, after a tramp of several hours across the darkened waste, we have reached the place appointed for observation. The pulsing stars are above and around - almost incredibly lustrous. In our journey we have disturbed many a wild creature in those mysterious avocations which are hardly even suspected by day. The long-drawn, nasal 'Yonk, yonk, yowe-e-aow' of many a questing jackal has sounded across the waste, awakening answers from kindred spirits far and

near.

At length we have reached the objective—a patch of low, loose bush some ten feet in diameter. About two hundred yards away is the nest; it will be in full view after day has come, for we are on an almost imperceptible rise. Pallid grows the east. For a while flaming Phosphor outshines the dawn, but soon merges into the general effulgence. Then the black, mound-like body of the sitting cock becomes visible. He lies as still as a rock, with his long, snake-like neck stretched straight before him on the sand, his wings and tail spread tent-wise over the raised margin of the nest. The white plumes are almost completely hidden under the drooping fringe of black feathers. Herein is an undoubted instance of protective coloration. The cock, being

jet-black, cannot be seen at night; the hen, which sits throughout the greater part of the day, is more or less the color of the desert sand. She thus attains a maximum of invisibility while on the nest.

At the appointed time the hens may be seen approaching - usually from different directions, but never in a straight line. They have, if the herbage be more than ordinarily scanty, perhaps slept miles away. At dawn they rose and started on their respective devious courses, cropping constantly at the herbage. When one of the hens has reached the vicinity of the nest, the cock will rise, carefully extracting his tarsi from among the eggs. As a rule the hen takes his place at once, but occasionally the eggs seem to be deliberately left to cool, as in the case of the domestic fowl. On one occasion I saw a cock come in swiftly from his feeding, sweep round the nest, and force the hen, which had left it, back to her incubation duties. He butted her with his breast-bone and showed every sign of indignation, flicking his wings and snapping his beak. It was evident that he considered that she had left the eggs for too long a period. The second hen usually sits on the edge of the nest, or, if eggs are lying outside the rim, she often sits on them. It was not possible to ascertain whether or not the same hen invariably took the most important position on the nest.

When the chicks have all become stronger on their legs, the parents lead them away to pastures they have already located, where suitable food is to be found. Should danger occur, the old birds utter a single note of alarm; then the cock hurries the brood away. Hissing violently, crouching forward and with her wings forming a fluttering shield before her body, the hen faces the enemy. This, it may be

noted, is the practice of all desert antelopes, whereas, in the flight of antelopes of the forest, it is the male which covers the retreat. To these rules there are, I think, no exceptions. But if, in the case of the ostrich brood, the danger be formidable and close at hand, the chicks will immediately scatter and squat, skillfully making use of any available inequality in the ground. Then the parents will endeavor to attract attention to themselves by falling to the ground and pretending to be injured. As the enemy approaches, the bird will spring up, run a short distance, and fall again. In this procedure the ostrich imitates the sand-piper with extraordinary exactness. The danger over, the chicks run about uttering their distinctive call. The parent birds do not reply; they move slowly about within the area containing the chicks, and their commanding height enables the latter to see and rally round them. The ostrich. knows its own chicks, and will kill any others seeking its protection.

One of the most remarkable habits of the ostrich is that of waltzing, or gyrating. So far as I have been able to ascertain, this habit is confined to domesticated birds. None of the old observers mention it. I have spoken to many Bushmen and others familiar with the ostrich in its wild state; not one of them had ever seen or heard of wild birds gyrating. I have personally had wild ostriches under observation from a place of concealment at every season and at each hour of the day, but never have I seen them gyrating. Yet among domesticated birds the practice is universal.

It is usually indulged in when they are released from an enclosure in the early morning. Then the birds will run swiftly for a short distance, stop suddenly, lift their wings, and spin rapidly round and round, using a perfect

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Taking into consideration the constant menace under which these birds exist in their natural environment, the general practice of gyration or of any exercise calculated to attract the attention of enemies, is unthinkable. The young wild ostrich survives only with difficulty, and largely owing to its inconspicuousness; probably not more than twenty per cent of those hatched out reach maturity. So far as one can judge, the gyration is a pure and simple expression of the joy of life-as natural a manifestation of healthy and exuberant vitality as is the dancing of children of all ages and climes. It is conventional, for all birds gyrate in exactly the same manner. It is to be accounted for only on the hypothesis of race-memory. Probably the ostrich did not always dwell in an environment of danger; countless ages ago the species may have had its origin in some vast Australian tract wherein carnivora were scarce. And now, when the age-long menace has been lifted from the domesticated birds, a hint whisper down the interminable, echoing corridors of the germ-plasm-may have awakened in them the long-dormant spirit of joy.

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Another remarkable habit of the

ostrich is that known as rolling. It is almost exclusively confined to the male bird. Under sexual excitement or anger a bird will sink down on his anklejoints with his tarsi horizontal, the tibia remaining erect. He will then open his wings forward and swish them alternately over his back. The head and neck, depressed backward, swing with the motion of the wings, the head striking the ribs on each side. The tail becomes widely distended. While thus engaged, the bird appears to be lost in an ecstasy of excitement; he becomes quite oblivious to his surroundings.

It is somewhat remarkable that erotic excitement and anger should be expressed in exactly the same manner. There is a kind of analogy to be found in certain behavior of the desert gazelle (Antidorcas euchore, miscalled the springbuck). This animal in its morning play expands and erects its dorsal mane of long snow-white hair, bends its back and sinks its head almost to the level of its hoofs. Then it bounds into the air, swaying from side to side. But if suddenly alarmed by an enemy, the gazelle acts in a precisely similar

manner.

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The ostrich emits several sounds, the best-known of which is the muffled roar known as the 'boom' or the 'brom,' which is uttered by the male bird either as a challenge to a rival or as a love-note to the hen. The sound is divided into three utterances, the first two being short and the third long, with an interval of about a second between. It is generated in a curious manner. The bird shuts its beak so tightly that no air can escape; then it empties the lungs into the œsophagus through the larynx, inflating the neck for its greater extent. The air thus flows backward over the vocal chords.

This sound has been compared to 'mourning' by the Prophet Micah; and at a certain distance, when some of the

elements have been subdued, it does convey a mournful suggestion. When heard close by, it suggests the utterance of an ox in pain, but at over a thousand yards it startlingly resembles the voice of the lion. The boom of the ostrich is but rarely heard by day, and the bird can utter it only when standing still. The other sounds are, respectively, a loud hiss of anger, a gurgle expressive of alarm, and the sharp note uttered to warn the chicks of danger.

The ostrich is usually a vegetarian, but his gizzard is a mill to which most objects capable of being swallowed are acceptable grist. It contains a number of large, rounded stones; almost invariably some of these are brightly colored. He will feed greedily upon locusts in the wingless stage, and apparently considers a young tortoise to be a tit-bit. Domesticated ostriches swallow the most extraordinary things; if one wears jewelry it is not safe to approach the fence of an enclosure in which friendly birds are kept. More More than one lady has discovered this to her cost. With a lightning-like sweep of its beak over or through a fence, a bird will annex a brooch, a locket, or any other glittering object. Tennisballs, kittens, the heels of glass bottles, cartridges, and small lengths of heavy wire, are among the articles which ostriches have been observed to swallow.

The plume of the ostrich is like nothing else in Nature. The nearest resemblance is to be found in an ephemeral thing - the foam of a breaking wave. It must be unthinkable ages since the wings of this bird subserved any use but that of beauty; their function in the matter of covering the eggs during incubation is quite secondary and could easily be dispensed with. The perfectly even barbs are soft as gossamer and, contrary to

the rule among birds that fly, quite disconnected and independent one of the other. The quills, from their point of emergence from the socket, become increasingly flexile and lithe. The plumes convey suggestions of luxuriant ductility, of effortless grace, of sumptuousness, and, above all, of purity. From very ancient days they have been used by man as a decoration, but not until quite recently by woman.

The beauty of the plumes of the ostrich and the mystery surrounding its habits, have ever attracted the interest of mankind. In ancient Egypt the plume, on account of the mathematical equality of the opposing barbs in point of length, in point of length, a peculiarity not present in the primary feathers of any other bird with which the Egyptians were acquainted-was regarded as the sacred symbol of Justice. Osiris was represented with two ostrich plumes in his crown. The hieroglyph for the plume was 'shoo.' This was probably onomatopoetic, and originated in the soft sound made by the plumes, when used as a fan.

The plume of the ostrich is in several respects the fairest thing which earth has produced. The creature which it glorifies is a member of an archaic class. Many of its congeners have disappeared; perhaps eliminated by the mammal carnivora; perhaps owing to their 'expensiveness,' as Lafcadio Hearn suggests in connection with the elimination of the dragons of the prime. One may see in certain museums the unbroken shell of the egg-fourteen inches in length-of the Epiornis, unearthed in Madagascar. The height of this bird possibly the roc of Eastern legend - may have been anything up to twenty feet. The Diornis of New Zealand-another gigantic relativewas probably in existence in the seventeenth century. Fossil bones of struthious birds have been found in

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