CHAPTER V.

EXTENT OF VARIATIONS IN ANIMAL AND VEGETABLE

RACES; APPLICATION TO MAN.

I. THE question to which this chapter is devoted is one of those which I shall treat most fully in this course.

In fact, it has a special importance. Nearly all the polygenistic arguments are included in the following:-"The difference between the Negro and the White is too great for them to belong to the same species." These types are the two extremes in the human series. Therefore, if it can be shown that between the two extremes, the limits of variation are almost always greater in plants and animals than in man, we shall have undermined the foundation of the whole polygenistic doctrine.

Now, even if we leave plants out of the question, and there can be little doubt in respect to them; if we merely compare man and animals, organ for organ, function for function, we shall have no great difficulty in arriving at the conclusion, that this is really the case; so much so that we shall be led to ask the question, why the variability is less in man than in animals. The complete demonstration of this general fact would require more extended treatment than I am able to give. I shall, therefore, confine myself to citing some examples.

II. The colouring of the skin is one of the most striking characteristics, and one which is most apparent to the eye. This has given rise to the expressions White, Yellow, and Black, which are most improperly used to designate the three fundamental groups of mankind. We will first prove that these names possess the grave inconvenience of giving

rise to ideas which are entirely erroneous. Amongst the Whites there are entire populations, whose skin is as black as that of the darkest Negro. I shall only quote the Bishareen and other tribes inhabiting the African coasts of the Red Sea, the black Moors of Senegal, etc. On the other hand, there are yellow Negroes, as the Bosjesmans, who are the colour of light mahogany, or of café au lait, as Livingstone tells us.

It is no less true that colour is by far the most variable characteristic in man, and when we place the coal black Negro side by side with the fair White with his pinkish complexion, the contrast is striking. But this contrast is repeated in several races of animals, in the dog, for example, whose skin is generally blackish, but white in the white poodle. It is the same among horses, a fact which was known even to Herodotus, who pronounces white horses with a black skin as superior to all others.

The races of our domestic fowls alone present the three extreme colours observed in man. The French fowl has a white skin; in the cochin-china it approaches to yellow; it is black in black fowls. Sometimes they present a peculiarity similar to that which I mentioned in reference to the horse: a dark skin accompanying a white plumage as in the silk hen of Japan.

These same black fouls possess several interesting peculiarities from our present point of view. In Europe, melanism appears from time to time in our poultry-yards, and would infallibly spread if the fowls attacked by it were not destroyed. It is perhaps from want of this precaution that black fowls have been developed in various parts of the globe, among others in the Philippines, in Java, in the Cape Verd Islands, and upon the plateau of Bogota, all of which have been derived from European stocks. Melanism appears moreover, in groups of fowls which differ most strikingly in other respects, in the silk hen as well as in our ordinary races.

We see that black fowls are in no sense a distinct species, and that the appearance of the black colour is merely an

accidental character, which may be produced in races very dissimilar in other respects, and afterwards propagated by heredity. Why then admit that it has been otherwise in man? Again, melanism is more highly developed in fowls than in man. It has long been held as a recognised fact that the skull of the Negro is more darkly coloured than that of the White. The fact is true. But M. Gubler has proved that the skull of a very dark complexioned White was coloured exactly in the same manner as that of the Negro, and that this peculiarity was sometimes individual, and sometimes hereditary in certain families. In fowls also, melanism penetrates to the interior; but it is not only the meninges which present peculiarities similar to those presented by the black man. With them all the mucous, fibrous, and aponeu rotic membranes, even to the muscular sheaths, possess the same colouring. The flesh also assumes a repugnant appearance, and it is for this reason that the propagation of black fowls is prevented as much as possible.

The difference in colouring is easily explained. We now know beyond a doubt that the skin of the Negro is exactly the same in composition as that of the White. We find the same layers in both; the dermis, the mucous layer and the epidermis present exactly the same structure. The layers are merely thicker in the Negro. In these two great races, the mucous layer, situated between the other two, is the seat of colour. It is formed of cells which are of a pale yellow colour in the fair White, of a more or less brownish yellow in the dark White, and of a blackish brown in the Negro. External causes have, moreover, an influence upon the organ and modify the coloured secretion. Simon has shown that freckles are nothing more than spots upon the skin of the White presenting the characteristics of the skin of the Negro, and we know that an unusual exposure to the sun in the men and women of our race, and pregnancy in the latter, is sufficient to determine the formation of these spots.

Why, then, should it be thought strange that a number of

circumstances, a constant heat, a bright light, &c., should influence the whole body and perpetuate those modifications which in us are only circumscribed and transitory. In treating of the formation of the human races we shall have to bring forward facts which will clearly prove that this is not merely hypothesis.

Finally, the colour of the skin depends upon a simple secretion which is subject to modification under a number of circumstances, as is the case with many others. There is therefore nothing strange in the fact that some human groups, differing widely in other respects, should resemble each other in the matter of colour. This is the reason why the Hindoo (Aryan), the Bisharee and the Moor (Semitic), although belonging to the White race, assume the same, and even a darker hue than the true Negro. It also explains the fact that the colour of the Negro approximates in certain cases, to that of peoples belonging to the white stock who are more or less of a brown colour, or assumes a hue which exactly recalls that of the yellow races.

Thus, in man, as in animals, the aphorism is verified which was formulated by Linnæus in regard to plants :-nimium ne crede colori.

III. I shall not dwell at any length upon the modifications of the hair and villosities. They are much more apparent than real in man. Whether fair or black, fine and of a woolly appearance, as in the Negro, or coarse and stiff, as in the yellow and red races; whether the transverse section is circular as in the Yellow race, oval, as in the White, or elliptic, as in the Negro, the hair remains hair. The woolly fleece of our sheep, on the contrary, is in part of Africa, replaced by a short and smooth bair. In America the same is the case with the sheep of the Madeleine whenever they are left unshorn; and on the other hand, in the high plains of the Andes, the wild boars acquire a kind of coarse wool.

The practice of certain natives of shaving off all hair has made some travellers believe in the existence of human

races which are entirely hairless; the error has however been recognised. All men possess hair in the normal places. Hairless dogs and horses are, however, known to exist. In America, where the oxen have a European origin, the hair commences with becoming very fine and few in number with the pelones, and disappears entirely with the calongos; and if the latter do not increase in number, it is due to their being systematically destroyed from an idea that they are a degenerate race.

It is evident that in these several respects the variations are more extensive in animals than in man.

IV. This fact becomes more evident when it is possible to substitute exact measurements for merely general ideas, and to compare figures. The variations in size present this advantage, and it is interesting to compare from this point of view the extremes of some animal races with the extremes admitted in human groups.

We see that the variation between races is in the horse twice as great as in man, nearly three times in the sheep and rabbit, and four times as much in the dog. The difference is perhaps even more striking in the goat and ox, judging from the terms of comparison used by several travellers.

If, after having studied the various dimensions of the body, we compare the differences in proportion presented on the