Part 2

The fowl's egg is formed in the body of the hen, and is, in fact, part of her body inclosed in a shell and detached. It contains a minute rudiment of a fowl; and when it is kept at a proper temperature by the hen's sitting upon it, or otherwise for three weeks, this rudiment grows, or develops, at the expense of the materials contained in the yolk and the white, into a small bird, the chick, which is then hatched and grows into a fowl. The animal, therefore, is produced by the development of a germ in the same way as the plant; and, in this respect, all plants and all animals agree with one another, and differ from all mineral matter.

Thus there is a very broad distinction between mineral matter and living matter. The elements of living matter are identical with those of mineral bodies; and the fundamental laws of matter and motion apply as much to living matter as to mineral matter; but every living body is, as it were, a complicated piece of mechanism which "goes," or lives, only under certain conditions. The germ contained in the fowl's egg requires nothing but a supply of warmth, within certain narrow limits of temperature, to build the molecules of the egg into the body of the chick. And the process of development of the egg, like that of the seed, is neither more nor less mysterious than that, in virtue of which, the molecules of water, when it is cooled down to the freezing-point, build themselves up into regular crystals.

The further study of living bodies leads to the province of biology, of which there are two great divisions--botany, which deals with plants, and zooelogy, which treats of animals.

Each of these divisions has its subdivisions--such as morphology, which treats of the form, structure, and development of living beings, and physiology, which explains their actions or functions, besides others.

[Illustration]

LIFE GROWTH;--FROGS

(FROM A SONG OF LIFE.)

BY MARGARET WARNER MORLEY.[1]

[1] Copyright by A. C. McClurg & Co., 1891.

[Illustration]

Somewhat higher than the fish in the scale of life is the frog. Although he begins life as a fish, and in the tadpole state breathes by gills, he soon discards the water-diluted air of the pond, and with perfect lungs boldly inhales the pure air of the upper world. His life as a tadpole, although so fish-like, is much inferior to true fish life: for though the fish has not the perfect lung, he has a modification of it which he fills with air, not for breathing purposes, but as an air-sac to make him float like a bubble in the water. Will he rise to the surface? he inflates the air-bladder. Will he sink to the bottom? he compresses the air-bladder. But in the frog the air-bladder changes into the lungs, and is never the delicate balloon which floats the fish in aqueous space. When the frog's lungs are perfected, his gills close, and he forever abandons fish-life, though being a cold-blooded creature he needs comparatively little air, and delights to return to his childhood's home in the bottom of the pond. But although he can stay under water for a long time, he is obliged to hold his breath while there, and when he would breathe must come to the surface to do so. It is possible to drown him by holding him under water.

[Illustration: A FROG.]

As a feeder the frog relies upon animal life, which he expertly seizes with a tongue fastened by the wrong end, as compared with our tongues. He is a certain marksman, and when he aims at an insect the chances are that the insect will enter his stomach and be there speedily changed into a new form of animal life.

Although from the moment the gills disappear the frog is a true land animal, he is obliged, on account of the fish-like character of his young, to lay his eggs in the water. For this purpose the frogs enter the pools in early spring. The surface of every country pond swarms with the bright-eyed little creatures. They have awakened from a long, cold, winter sleep, to find the spring about them and within them. Life has suddenly become abundant and joyous. Their sluggish blood flows faster, their hearts beat quicker; they leap, they swim, they swell out their throats and call to each other in various keys. The toads are with them, and the pretty tree-frogs that change their color to suit their emotions. And all are rapturously screaming. Their voices are not musical, according to man's standard, but seem to afford great satisfaction to the performers in the shrill orchestra of the swamps, who thus give vent to the flood of life that sweeps through them after the still, icy winter.

As though the new spring-life were too plentiful to find room in the frogs and toads already existing, it calls for more frogs and toads; and new creatures are born to share the extra vitality. Like the flowers and the fish, the frogs, too, give forth new life. Within them, too, the miracle is performed. The tiny eggs of the one wake up and begin to grow. The tiny living bodies in the fertilizing principle of the other also wake up and begin to grow. But higher life is better guarded, because less prolific. The frog and the toad lay but few eggs as compared with the fish. Fish eggs may drop under the stones or float away, and so escape the vital touch of the fertilizing principle. There are so many that numbers may be lost and yet enough remain to continue the family. Not so with the frog family. No egg may be lost. So we find that the eggs of the frog are not dropped singly, like so many shot, but are bound together by a colorless, transparent, jelly-like substance, much like that found in the morning-glory seed, and which like that supplies nourishment to the young life, for the tadpole feeds upon it until he is able to seek other food. Moreover, instinct has taught the frog the need of extreme caution in the act of fertilization. Every egg _must_ be fertilized. As the time draws near for the dropping of the few eggs into the water, the male frog so places himself that the moment the eggs are being laid, he pours over them, one by one, as they fall into the water, the fertilizing fluid.

And thus the mystery of life is again repeated. The union of the living, microscopic bodies of the fertilizing principle with the new laid egg is followed by the growth of the two elements into a living creature, able to eat, to breathe, to see, to feel. In some unknown way the atom of fertilizing principle seems to have contained the whole life of the father-frog, for it can give to his sons and daughters any of his peculiarities, either of color, form, motion, or disposition; and the tiny egg seems to have contained the whole life of the mother-frog, and can give to her sons and daughters any of her peculiarities; though, as is true of all inheritance, the tadpoles, as the young frogs are called, share the natures of both parents, inheriting some peculiarities from the father and others from the mother.

[Illustration: A FROG.]

But, like other life, although the frogs may vary a good deal within frog limits, none of them can escape their own limits and enter into those of any other life. Once a frog, always a frog; and no frog-egg may hope to develop into a turtle, or a bird, or anything but a frog. The life in the fertilizing principle of the frog is sacred to frog eggs, and is lifeless in contact with any other.

Our common frogs, like many of the fishes, do not trouble themselves about the fate of their eggs after they are carefully laid in a safe place. They trust Mother Nature to see the little tadpoles safely through the perils of childhood, to help them change their dresses and get rid of their tails, and cut, not their teeth, but their arms and legs.

In Venezuela, however, there dwells a frog with well developed maternal instinct. The mothers have pockets on their backs, not for their own convenience, but as cradles for their babies. The fathers put the fertilized eggs into the pockets of the mothers; and there they remain, well guarded, until the young are able to care for themselves.

[Illustration: TADPOLES.]

THE MAN-LIKE APES

(FROM EVIDENCE AS TO MAN'S PLACE IN NATURE.)

BY PROFESSOR T. H. HUXLEY.

[Illustration: HEAD OF GORILLA.]

Sound knowledge respecting the habits and mode of life of the man-like Apes has been even more difficult of attainment than correct information regarding their structure.

Once in a generation, a Wallace may be found physically, mentally, and morally qualified to wander unscathed through the tropical wilds of America and of Asia, to form magnificent collections as he wanders, and withal to think out sagaciously the conclusions suggested by his collections; but, to the ordinary explorer or collector, the dense forests of equatorial Asia and Africa, which constitute the favorite habitation of the Orang, the Chimpanzee, and the Gorilla, present difficulties of no ordinary magnitude; and the man who risks his life by even a short visit to the malarious shores of those regions may well be excused if he shrinks from facing the dangers of the interior; if he contents himself with stimulating the industry of the better-seasoned natives, and collecting and collating the more or less mythical reports and traditions with which they are too ready to supply him.

In such a manner most of the earlier accounts of the habits of the man-like Apes originated; and even now a good deal of what passes current must be admitted to have no very safe foundation. The best information we possess is that based almost wholly on direct European testimony respecting the Gibbons; the next best evidence relates to the Orangs; while our knowledge of the habits of the Chimpanzee and the Gorilla stands much in need of support and enlargement by additional testimony from instructed European eye-witnesses.

It will therefore be convenient in endeavoring to form a notion of what we are justified in believing about these animals, to commence with the best known man-like Apes, the Gibbons, and Orangs; and to make use of the perfectly reliable information respecting them as a sort of criterion of the probable truth or falsehood of assertions respecting the others.

Of the Gibbons, half a dozen species are found scattered over the Asiatic Islands, Java, Sumatra, Borneo, and through Malacca, Siam, Arracan, and an uncertain extent of Hindostan on the mainland of Asia. The largest attain a few inches above three feet in height, from the crown to the heel, so that they are shorter than the other man-like Apes, while the slenderness of their bodies renders their mass far smaller in proportion even to this diminished height.

Dr. Salomon Mueller, an accomplished Dutch naturalist, who lived for many years in the Eastern Archipelago, and to the result of whose personal experience I shall frequently have occasion to refer, states that the Gibbons are true mountaineers, loving the slopes and edges of the hills, though they rarely ascend beyond the limit of the fig-trees. All day long they haunt the tops of the tall trees, and though toward evening, they descend in small troops to the open ground, no sooner do they spy a man than they dart up the hillsides and disappear in the darker valleys.

All observers testify to the prodigious volume of voice possessed by these animals. According to the writer whom I have just cited, in one of them, the Siamang, "the voice is grave and penetrating, resembling the sounds goek, goek, goek, goek, goek ha ha ha ha haaaaa, and may be easily heard at a distance of half a league." While the cry is being uttered, the great membranous bag under the throat which communicates with the organ of voice, the so-called "laryngeal sac," becomes greatly distended, diminishing again when the creature relapses into silence.

M. Duvaucel, likewise, affirms that the cry of the Siamang may be heard for miles--making the woods ring again. So Mr. Martin describes the cry of the agile Gibbon as "overpowering and deafening" in a room, and "from its strength, well calculated for resounding through the vast forests." Mr. Waterhouse, an accomplished musician as well as zooelogist, says, "The Gibbon's voice is certainly much more powerful than that of any singer I ever heard." And yet it is to be recollected that this animal is not half the height of, and far less bulky in proportion than, a man.

[Illustration: A GIBBON.]

There is good testimony that various species of Gibbon readily take to the erect posture. Mr. George Bennett, a very excellent observer, in describing the habits of a male _Hylobates syndactylus_ which remained for some time in his possession, says: "He invariably walks in the erect posture when on a level surface; and then the arms either hang down, enabling him to assist himself with his knuckles; or, what is more usual, he keeps his arms uplifted in nearly an erect position, with the hands pendent ready to seize a rope, and climb up on the approach of danger or on the obtrusion of strangers. He walks rather quick in the erect posture, but with a waddling gait, and is soon run down if, while pursued, he has no opportunity of escaping by climbing.... When he walks in the erect posture, he turns the leg and foot outward, which occasions him to have a waddling gait and to seem bow-legged."

Dr. Burrough states of another Gibbon, the Horlack or Hooluk:

"They walk erect; and when placed on the floor, or in an open field, balance themselves very prettily by raising their hands over their head and slightly bending the arm at the wrist and elbow, and then run tolerably fast, rocking from side to side; and, if urged to greater speed, they let fall their hands to the ground, and assist themselves forward, rather jumping than running, still keeping the body, however, nearly erect."

Somewhat different evidence, however, is given by Dr. Winslow Lewis:

"Their only manner of walking was on their posterior or inferior extremities, the others being raised upward to preserve their equilibrium, as rope-dancers are assisted by long poles at fairs. Their progression was not by placing one foot before the other, but by simultaneously using both, as in jumping." Dr. Salomon Mueller also states that the Gibbons progress upon the ground by short series of tottering jumps, effected only by the hind limbs, the body being held altogether upright.

But Mr. Martin, who also speaks from direct observation, says of the Gibbons generally:

"Pre-eminently qualified for arboreal habits, and displaying among the branches amazing activity, the Gibbons are not so awkward or embarrassed on a level surface as might be imagined. They walk erect with a waddling or unsteady gait, but at a quick pace, the equilibrium of the body requiring to be kept up, either by touching the ground with the knuckles, first on one side then on the other, or by uplifting the arms so as to poise it. As with the Chimpanzee, the whole of the narrow, long sole of the foot is placed upon the ground at once, and raised at once, without any elasticity of step."

After this mass of concurrent and independent testimony, it cannot reasonably be doubted that the Gibbons commonly and habitually assume the erect attitude.

But level ground is not the place where these animals can display their very remarkable and peculiar locomotive powers, and that prodigious activity which almost tempts one to rank them among flying, rather than among ordinary climbing mammals.

Mr. Martin has given so excellent and graphic an account of the movements of a _Hylobates agilis_, living in the Zooelogical Gardens, in 1840, that I will quote it in full:

"It is almost impossible to convey in words an idea of the quickness and graceful address of her movements: they may indeed be termed aerial, as she seems merely to touch in her progress the branches among which she exhibits her evolutions. In these feats her hands and arms are the sole organs of locomotion, her body, hanging as if suspended by a rope, sustained by one hand (the right, for example), she launches herself, by an energetic movement, to a distant branch, which she catches with the left hand; but her hold is less than momentary; the impulse for the next launch is acquired; the branch then aimed at is attained by the right hand again, and quitted instantaneously, and so on, in alternate succession. In this manner spaces of twelve and eighteen feet are cleared, with the greatest ease and uninterruptedly, for hours together, without the slightest appearance of fatigue being manifested; and it is evident that, if more space could be allowed, distances very greatly exceeding eighteen feet would be as easily cleared; so that Duvaucel's assertion that he has seen these animals launch themselves from one branch to another, forty feet asunder, startling as it is, may be well credited. Sometimes, on seizing a branch in her progress, she will throw herself, by the power of one arm only, completely round it, making a revolution with such rapidity as almost to deceive the eye, and continue her progress with undiminished velocity. It is singular to observe how suddenly this Gibbon can stop, when the impetus giving by the rapidity and distance of her swinging leaps would seem to require a gradual abatement of her movements. In the very midst of her flight a branch is seized, the body raised, and she is seen, as if by magic, quietly seated on it, grasping it with her feet. As suddenly she again throws herself into action.

"The following facts will convey some notion of her dexterity and quickness. A live bird was let loose in her apartment; she marked its flight, made a long swing to a distant branch, caught the bird with one hand in her passage, and attained the branch with her other hand, her aim, both at the bird and at the branch, being as successful as if one object only had engaged her attention. It may be added that she instantly bit off the head of the bird, picked its feathers, and then threw it down without attempting to eat it.

"On another occasion this animal swung herself from a perch, across a passage at least twelve feet wide, against a window which it was thought would be immediately broken: but not so; to the surprise of all, she caught the narrow framework between the panes with her hand, in an instant attained the proper impetus, and sprang back again to the cage she had left--a feat requiring not only great strength, but the nicest precision."

The Gibbons appear to be naturally very gentle, but there is very good evidence that they will bite severely when irritated, a female _Hylobates agilis_ having so severely lacerated one man with her long canines that he died; while she had injured others so much that, by way of precaution, these formidable teeth had been filed down; but if threatened she would still turn on her keeper. The Gibbons eat insects, but appear generally to avoid animal food. A Siamang, however, was seen by Mr. Bennett to seize and devour greedily a live lizard. They commonly drink by dipping their fingers in the liquid and then licking them. It is asserted that they sleep in a sitting posture.

Duvaucel affirms that he has seen the females carry their young to the water-side and there wash their faces, in spite of resistance and cries. They are gentle and affectionate in captivity--full of tricks and pettishness, like spoiled children, and yet not devoid of a certain conscience, as an anecdote, told by Mr. Bennett will show. It would appear that his Gibbon had a peculiar inclination for disarranging things in the cabin. Among these articles a piece of soap would especially attract his notice, and for the removal of this he had been once or twice scolded. "One morning," says Mr. Bennett, "I was writing, the Ape being present in the cabin, when, casting my eyes toward him, I saw the little fellow taking the soap. I watched him without him perceiving that I did so: and he occasionally would cast a furtive glance toward the place where I sat. I pretended to write; he seeing me busily occupied, took the soap, and moved away with it in his paw. When he had walked half the length of the cabin, I spoke quietly, without frightening him. The instant he found I saw him he walked back again and deposited the soap nearly in the same place from whence he had taken it. There was certainly something more than instinct in that action: he evidently betrayed a consciousness of having done wrong both by his first and last actions--and what is reason if that is not an exercise of it?"

The most elaborate account of the natural history of the Orang-Utan extant is that given in the "_Verhandelingen over de Natuurlijke Geschiedenis der Nederlandsche overzeeche Bezittingen (1839-45)_," by Dr. Salomon Mueller and Dr. Schlegel, and I shall base what I have to say upon this subject almost entirely on their statements, adding here and there particulars of interest from the writings of Brooke, Wallace, and others.

The Orang-Utan would rarely seem to exceed four feet in height, but the body is very bulky, measuring two thirds of the height in circumference.

The Orang-Utan is found only in Sumatra and Borneo, and is common in either of these islands--in both of which it occurs always in low, flat plains, never in the mountains. It loves the densest and most sombre of the forests, which extend from the seashore inland, and thus is found only in the eastern half of Sumatra, where alone such forests occur, though, occasionally, it strays over to the western side.

On the other hand it is generally distributed through Borneo, except in the mountains, or where the population is dense. In favorable places the hunter may, by good fortune, see three or four in a day.

[Illustration: HEAD OF ORANG-UTAN.]

Except in the pairing time, the old males usually live by themselves. The old females and the immature males, on the other hand, are often met with in twos and threes; and the former occasionally have young with them, though the pregnant females usually separate themselves, and sometimes remain apart after they have given birth to their offspring. The young Orangs seem to remain unusually long under their mother's protection, probably in consequence of their slow growth. While climbing the mother always carries her young against her bosom, the young holding on by the mother's hair. At what time of life the Orang-Utan becomes capable of propagation, and how long the females go with young is unknown, but it is probable that they are not adult until they arrive at ten or fifteen years of age. A female which lived for five years at Batavia had not attained one-third the height of the wild females. It is probable that, after reaching adult years, they go on growing, though slowly, and that they live to forty or fifty years. The Dyaks tell of old Orangs which have not only lost all their teeth, but which find it so troublesome to climb that they maintain themselves on windfalls and juicy herbage.