resentative among living forms of the Hominidæ, the highest family of the order of Primates. To the species, man, Linnæus gave the scientific name of Homo sapiens, this being regarded by him as the primitive species which has diverged into several geographical varieties or races. Of these, at least three might well be regarded as distinct species. The form called by Linnæus Homo sapiens europaus includes not only the white men of Europe, but allied races of Africa and Asia, as the Moors, the Jews, the Turks, the Arabs, the Hindus and the Ainus of northern Japan. To Homo asiaticus belong

000

FIG. 282.-Upper teeth of man and the orang-utan: At left, of a Caucasian; in middle. of a negro; at right, of a grown orang-utan. The condition in the negro is between that in the orang-utan and that in the Caucasian. (After Wiedersheim.)

the Mongolian races, probably the Esquimaux and Aleuts of North America, and perhaps the American Indians (Homo americanus), with the Malays, the South Sea Islanders, and the Australians as well. Homo afer of Africa and adjacent islands comprises the kinky-haired negroes and negritos.

Structurally the members of the genus Homo are closely allied to the anthropoid apes. The actual differences in anatomy are very slight. The differences in degree of mental endowment are enormous, but it can be shown that these distinctions are, for the most part, of degree only, associated with the greater size and greater degree of specialization of the brain of man. Homologies of the closest sort exist, involving every element in structure as well as every function of the organism and every known mental attribute. The anthropoid or manlike apes constitute the family of Simiidæ. The principal species are the following, beginning with the lowest or most monkeylike: Hylobates, the gibbons, of several species, notable

The order of primates has been variously classified. It is conveniently divided into five principal groups: (a) the lemurs (including Lemurida, Cheiromyidæ, Galeopithecidæ, and still

thumb on each foot. Monkeylike in their feet and in their general habit, yet in appearance they have little to suggest affinity with man. In general make-up, they are superficially comparable rather with weasels, squirrels, and bats.

The New-World monkeys differ widely from the others. Technically they are distinguished by the diverging (platyrrhine) nostrils, and by the retention of the primitively larger number of teeth. Many of them have prehensile tails, and in habit and temper all are very unlike the more hardy and pugnacious monkeys of the Old World. All the Old-World monkeys as well as the apes and man have parallel nostrils, directed downward (catarrhine). Their tails, if present, are not prehensile, and in their habits and temper they approach progressively toward man. Catarrhine monkeys are known to have existed in the Miocene period. The anthropoid apes represent a high degree of

advancement within the same group which finds its final extreme in the genus Homo.

Considering structural characters alone, it is readily conceivable that man should have had an anthropoid ancestry, that the anthropoids should have sprung from an Old-World monkey stock, and that the Old-World monkeys in turn are derived from the lemurs. It is not supposable that any living species of man has sprung from any extant species of anthropoid ape. The point of juncture is clearly far back in the earlier Tertiary times, but morphological evidence points to the common origin of primitive man and the known anthropoids. It is, of course, certain that the intermediate forms when known

will not be strictly man-apes, nor ape-men, but rather primitive creatures uniting the possibilities of both. From that condition. men and apes have since

diverged and will continue to diverge.

There is no doubt of the truth of Huxley's statement:

"Thus whatever system of organs be studied, the comparison of their modifications in the ape series leads to one and the same result-that the structural differences which separate man from the gorilla and the chimpanzee are not so great as those which separate the gorilla from the lower apes."

FIG. 286.-Head of gorilla. (After Brehm.)

In fact, as Haeckel has observed,

"It is very difficult to show why man should not be classed with the large apes in the same zoological family. We all know a man from

an ape, but it is quite another thing to find differences which are absolute and not of degree only."

It may be broadly stated that man differs from the apes in the combination of the following characters: (1) Erect walk; (2) extremities differentiated accordingly, the great toe not being opposable, the other toes little prehensile; (3) articulate speech; (4) higher reasoning power. The erect walk is not an absolute character. The higher apes walk on their feet, touching the ground at times with their knuckles. The tailed monkeys

FIG. 287.-Face of gorilla. (After Brehm.)

walk like a bear, four-footed, and resting on the palms of their hands. The muscles in each case are the same, although in man the gastrocnemius and soleus are enlarged, forming the calf of the leg, while the expanded gluteus maximus forms the buttocks. Both buttocks and calf are scantily developed in the apes and monkeys, but the muscles forming them are essentially the same as in man.

The monkeys have been called Quadrumana, four-handed. because the foot like the hand is fitted for grasping, and the

great toe, like the thumb, is opposable to the other digits. But as Huxley has clearly shown, this modification involves no real change of structure. An examination of the bones and muscles involved at once shows that the hinder limb in apes and monkeys is truly a foot and not a hand. Part by part the hinder foot of the monkey is homologous with the foot of man, not with the hand (Fig. 281). The loss of the power of opposing the great toe, on the part of man, is a result incident to

the use of the hinder limbs for walking alone, and not for grasping. In some of the lower races of man the great toe stands apart from the others to a larger extent than in the European races.

In the apes there is a greater degree of mobility of the muscles of the scalp and the ear than in man, but there are very many cases of men who are able to move these muscles freely. The muscles of the tail in man are quite useless, as are also those of the higher apes, in which the coccyx or tail is scarcely more developed than in man.

In man, the wisdom teeth are usually rudimentary, but in the native Australians these teeth are the largest of the series, as is also the case with the apes (Fig. 282).

In structure it is clear that man agrees in all large matters