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building up the strata containing the remains of its vast successions of plants and animals. These are now accounted for on the theory that geological time extends over millions of years. It is true that man reaches back comparatively little way into this immense lapse of time. Yet his first appearance on earth goes back to an age compared with which the ancients, as we call them, are but moderns. The few thousand years of recorded history only take us back to a præhistoric period of untold length, during which took place the primary distribution of mankind over the earth and the development of the great races, the formation of speech and the settlement of the great families of language, and the growth of culture up to the levels of the old world nations of the East, the forerunners and founders of modern civilized life.

Having now sketched what history, archæology, and geology teach as to man's age and course on the earth, we shall proceed in the following chapters to describe more fully Man and his varieties as they appear in natural history, next examining the nature and growth of Language, and afterwards the development of the knowledge, arts, and institutions, which make up Civilization.

CHAPTER II.

MAN AND OTHER ANIMALS.

Vertebrate Animals, 35-Succession and Descent of Species, 37-Apes and Man, comparison of structure, 38-Hands and Feet, 42-Hair, 44-Features, 44—Brain, 45—Mind in Lower Animals and Man, 47.

To understand rightly the construction of the human body, and to compare our own limbs and organs with those of other animals, requires a thorough knowledge of anatomy and physiology. It will not be attempted here to draw up an abstract of these sciences, for which such handbooks should be studied as Huxley's Elementary Physiology and Mivart's Elementary Anatomy. But it will be useful to give a slight outline of the evidence as to man's place in the animal world, which may be done without requiring special knowledge in the reader.

That the bodies of other animals more or less correspond in structure to our own is one of the lessons we begin to learn in the nursery. Boys playing at horses, one on all-fours and the other astride on his back, have already some notion how the imagined horse matches a real one as to head, eyes, and ears, mouth and teeth, back and legs. If one questions a country lad sitting on a stile watching the hunters go by, he knows well enough that the huntsman and his horse, the hounds and the hare they

are chasing, are all creatures built up on the same kind of bony scaffolding or skeleton, that their life is carried on by means of similar organs, lungs to breathe with, a stomach to digest the food taken in by the mouth and gullet, a heart to drive the blood through the vessels, while the eyes, ears, and nostrils receive in them all in like manner the impressions of sight, hearing, and smell. Very likely the peasant has taken all this as a matter of course without ever reflecting on it, and even more educated people are apt to do the same. Had it come as a new discovery, it would have set any intelligent mind thinking what must be the tie or connexion between creatures thus formed as it were on one original pattern, only varied in different modes for different ends. The scientific comparison of animals, even when made in the most elementary way, does at once bring this great problem before our minds. In some cases, more exact knowledge shows that the first rough comparison of man and beast may want correction. For instance, when a man's skeleton and a horse's are set side by side, it becomes plain that the horse's knee and hock do not answer, as is popularly supposed, to our elbow and knee, but to our wrist and ankle. The examination of the man's limb and the horse's leads to a further and remarkable conclusion, that the horse's fore- and hind leg really cor respond to a man's arm and leg in which all the fingers and toes should have become useless and shrunk away, except one finger and one toe, which are left to be walked upon, with the nail become a hoof. The general law to be learnt from the series of skeletons in a natural history museum, is that through order after order of fishes, reptiles, birds, beasts, up to man himself, a common type or pattern may be traced, belonging to all animals which are vertebrate, that is, which have a backbone. Limbs may still be recognised

though their shape and service have changed, and though they may even have dwindled into remnants, as if left not for use, but to keep up the old model. Thus, although a perch's skeleton differs so much from a man's, its pectoral and ventral fins still correspond to arms and legs. Snakes are mostly limbless, yet there are forms which connect them with the quadrupeds, as for instance, the boa-constrictor's skeleton shows a pair of rudimentary hind-legs. The Greenland whale has no visible hind-limbs, and its fore-limbs are paddles or flippers, yet when dissected, the skeleton shows not only remnants of what in man would be the leg-bones, but the flipper actually has within it the set of bones which belong to the human arm and hand. It is popularly considered that man is especially distinguished from the lower animals by not having a tail; yet the tail is plainly to be seen in the human skeleton, represented by the last tapering vertebræ of the spine.

All these are animals now living. But geology shows that in long-past ages the earth has been inhabited by species different from those at present existing, and yet evidently related to them. In the tertiary period, Australia was distinguished as now by its marsupial or pouched animals, but these were not of any present species, and mostly far larger; even the tallest kangaroo now to be seen is a puny creature in comparison with the enormous extinct diprotodon, whose skull was three feet long. So in South America there lived huge edentate animals, now poorly represented by the sloths, anteaters and armadillos, to be seen in our Zoological Gardens. Elephants are found fossil in the miocene deposits, but the species were all different from those in Africa and India now. These are common examples of the great principle now received by all zoologists, that from remote geological antiquity

there have from time to time appeared on earth new species of animals, so far similar to those which came before them as to look as if the old types had been altered to fit new conditions of life, the earlier forms then tending to die out and disappear. This relation between the older species of vertebrate animals and the newer species which have supplanted them, is a matter of actual observation, and beyond dispute. Many zoologists, now perhaps the majority, go a step farther than this, not only acknowledging that there is a relation between the new species and the old, but seeking to explain it by the hypothesis of descent or development, now often called, from its great modern expounder, the Darwinian theory. The formation of breeds or varieties of animals being an admitted fact, it is argued that natural variation under changed conditions of life can go far enough to produce new species, which by better adaptation to climate and circumstances may supplant the old. On this theory, the present kangaroos of Australia, sloths of South America, and elephants of India, are not only the successors but the actual descendants of extinct ones, and the fossil bones of tertiary horse-like animals with three-toed and four toed feet show what the remote ancestors of our horses were like, in ages before the unused toes dwindled to the splintbones which represent them in the horse's leg now. According to the doctrine of descent, when several species of animals living at the same time show close resemblance in structure, it is inferred that this resemblance must have been inherited by all from one ancestral species. Now of all the mammalia, or animals which suckle their young, those whose structure brings them closest to man are the apes or monkeys, and among these the catarhine or nearnostrilled apes of the Old World, and among these the group called anthropoid or manlike, which inhabit tropical

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