The human species

by A. de Quatrefages

The maximum individual variation is then 46·87.

Upon examining the table of M. Broca, we find that the white races are represented in the three groups. The Dutch of Zaandam figure among the megasemes between the aborigines of Mexico and those of North-west America. The Gallo-Bretons are placed in the same group, between the Chilians and the Indo-Chinese. The Whites form the great majority in the group of mesosemes, and are much the most numerous in that of the microsemes. One of their races indeed, the natives of Teneriffe, terminates the series, immediately preceded by the Tasmanians and Australians.

Thus, as far as the white race is concerned, the mean orbital index proclaims an intercrossing comparable with all that we have hitherto observed. The case is different with the two other fundamental types. They are distinctly separated by this character. All the yellow races are megasemes, for in my opinion the Lapps, considered by M. Broca to belong to them, are in reality allophylian Whites. All the negro races are mesosemes or microsemes. There is a difference of 4·03 between the aborigines of Brazil representing the last megasemes which have not been deformed, and the Papuans of Toud Island, who have, of all Blacks, the highest orbital index.

The usual intercrossing would undoubtedly reappear if we took individual variations into consideration. The difference 9·89 which separates the man of Cro-Magnon from the woman of the same race is sufficient proof.

M. Broca has studied the influence of sex and age upon the orbital index. I cannot follow him into these details, however interesting they may be. I will only remark, that, as in the case of the nasal index, it diminishes with the progress of evolution, and remains in all races greater in the woman than in the man. The latter preserves, then, throughout life, a certain infantile character.

This observation applies equally to races distinguished for the size of their orbital index. The yellow races, including the Chinese, present therefore, if compared with white races, an arrest of evolution. Yet the Chinese are far superior to all the microseme or mesoseme black races, and particularly the Australians and Tasmanians, who are only followed by the inhabitants of Teneriffe in the lowest places of the table. If we take the white as the normal type, we must regard these two populations as presenting an excess of evolution; but this excess is still more marked in the Guanches of Teneriffe, who, in their mode of life, are considerably superior to the Tasmanians and Australians.

A general conclusion follows from these facts, namely: that the characters resulting from an arrest or excess of evolution, are not of themselves a sign of superiority or inferiority.

M. Broca has, with great propriety, compared the orbital index of apes with that of man. As might easily have been foreseen, the laws of development are the same in the highest groups of apes as in man. The influence of sex and age are as noticeable in the gorilla, the orang, and in the chimpanzee as in our own races. It seems to be less striking in the lower apes.

The orbital index groups apes, like man, into megasemes, mesosemes and microsemes. But this character connects the anthropomorphous apes with the lowest types, with the cebidæ, and even the lemuridæ, which we now, from their embryogeny, connect with the ruminants or edentata. The genera of simiadæ are divided into three groups. M. Broca draws from these facts the very first conclusion that no value, as characterising gradations, can be attributed to the orbital index.

It is well known that in the Negro the entire face, and especially the lower portion, projects forward. This trait has been termed prognathism. In the living subject it is exaggerated by the thickness of the lips. But it is also apparent in the skull, and constitutes one of its most striking characters. M. Topinard has studied it in a special manner, and by a method of his own. He has with justice separated facial prognathism, which embraces the entire face, from the various maxillary and dental prognathisms, which distinctions I proposed some time ago. The index is here furnished by the relation existing between the height, and the horizontal projection of the region under consideration. But M. Topinard has recently replaced this index by the angle formed by the profile lines with the horizontal plane. This is a happy modification, as it presents a more precise idea to the mind.