We have now another question to consider. Should these white, yellow, or black men, to whom we must add, as we shall see later on, those who are brown and red, all of whom differ one from another in the colour of their skin, in height, in their physiognomy, and in their outward appearance, be grouped into different species, or are we to regard them merely as varieties of species—that is to say, races? To fully understand this question and to form a judgment of what will result from it, we must ascertain what is understood in natural history by the word species, and by the word race or variety of species. We will therefore commence by explaining the meaning of species in zoology.
The hare and the rabbit, the horse and the ass, the dog and the wolf, the stag and the reindeer, &c., are not likely to be taken one for another. Yet how greatly do dogs differ among themselves in size, in colour, and in their proportions. What a difference there is between the mastiff and the Pyrenean dog! The same observation applies to horses. How different we find in size and outward appearance the large Normandy horse, the London dray horse, or the omnibus horse of Paris, and the small Corsican or Shetland horses which we can carry in our arms! And yet no one is mistaken in them: whether he differ in size, or in the colour of his hair, we always recognise a horse, and never mistake him for an ass; in the mastiff as well as in the bulldog, we shall always recognise a dog. However greatly a rabbit may vary in size and colour, it will never be taken for a hare. The Breton cow, slight and frail, is nevertheless as much a cow in the eyes of a farmer, and the rest of the world, as a full-sized Durham. The same reflection applies with equal force to birds. The turkey which exists in the wild state in America, certainly differs very much from the black or white turkey acclimatized in Europe; but there is no mistake that both of them are turkeys, and nothing else.
The vegetable kingdom will furnish us with similar facts. Take, for instance, the cotton plant on its native soil in America, and you will find that it differs from the cotton plant cultivated in Africa and Asia. The coffee plant of the South American plantations is not similar to the same shrub which exists in Arabia, whence it came in the first instance. Wheat varies with latitude to a most extraordinary extent, &c. The cotton plant, however, is always the cotton plant, whatever be the soil upon which it grows; the coffee plant and wheat are always the same vegetables, and one is not liable to be deceived in them. The action of climate and soil upon vegetables, these same causes taken in connection with nutrition upon animals, and finally the mixture which has taken place between different individuals, explain all these differences, which affect the external appearance, but not the type itself.
We mean by species, when applied either to animals or vegetables, the fundamental type, and by variety or race the different beings which result from the influence of climate, of nutriment, and of mixture with individuals of the same species. The species dog gives birth to the varieties or races known under the names of bull-dog, spaniel, mastiff, &c. The species horse gives birth to the races or varieties known under the names of the Arabian, English, Normandy, Corsican, &c. The species turkey produces the varieties known as the wild turkey, the black and the white turkey. In the vegetable kingdom, the cotton plant species produces the American and the Indian cotton; the bramble produces the innumerable varieties which are known to us as rose-trees.
But, the reader will say, how are we to distinguish race from species, and does there exist any practical means of deciding whether the animal under consideration belongs to a species or a race? We reply that such a means does exist, which enables us to speak with certainty in every case. It is of importance that this should be made known in order that every one may test it for himself.
Take the two animals in question, unite them, and if that connexion of the sexes results in the production of another individual, capable of reproduction, this will indicate race or variety. If, however, the union of the two individuals is unproductive, or the offspring is itself barren, this will indicate two individuals of different species.
In spite of observations and experiments made in the course of many thousand years, reproduction has never been procured by mixture of a rabbit with a hare, a wolf with a dog, a sheep with a goat. It is true that hybrids are obtained between the horse and she-ass, and between the ass and the mare, but it is well known that the individuals produced by this mixture, namely, the quadrupeds termed mules, are barren animals, incapable of reproduction with one another.
This rule is not confined to the animal kingdom, but it obtains also among vegetables. You can obtain artificial production from a pear tree by applying, with suitable precautions, the pollen of the flowers of one pear tree to the stamens of those of another. Fruit will be formed, and the seed which that produces will in its turn be productive. But if you attempt to perform the same operation between a pear tree and an apple tree, you will obtain no result whatever. This, again, is the practical method which enables botanists to distinguish varieties from species. The test of artificial fecundation between one plant and another, which it is desired to distinguish as regards their species, serves to solve the difficulties which are met in attempting to determine the position of a plant in botanical classification.
The word species therefore is not a fictitious term, a conventional expression invented by the learned to designate the classifications of living beings. A species is a group arranged by Nature herself. Fruitfulness or barrenness in the products of the mixture are the characteristics which Nature attaches to variety or to species; those groups therefore appear to us as though they had a substantial foundation in the laws which govern living beings, and we do but render in speech what we observe in Nature.
When, moreover, we reflect, we easily understand that if Nature had not instituted species the most complete disorder would have reigned throughout living creation. By intermixture the animal kingdom would have been overrun by mongrels who would have confused every type, thus permitting of no discernment in this crowd of incoherent products. The whole animal kingdom would have been given over to inextricable confusion. In like manner, if plants had been capable of infinite variety through the mixture of different species, brought about by the industry of man, or by the effect of the wind bearing through the air the fertilizing pollen, there would be nought but trouble and disorder among the vegetable population of the globe.
Species therefore has a necessary, providential, and fixed existence. Impossibility of union is the distinctive qualification which nature assigns to this group of living beings. Reproduction is possible only between members of the same species, and the differences produced in their offspring by the soil, nutriment and surrounding circumstances, determine what we call race, or variety.
The principle which we have just enunciated, will in its application to man enable us to decide whether the individuals that people the globe, belong to different species of men, or simply to races or varieties; in other words, whether the human species is unique, and whether the different human types known to us, the white, black, yellow, brown and red-man, belong or not to races of the human species.
The reply to this question will doubtless have been anticipated. If we apply the rule stated above, all men that inhabit the globe belong to one and the same species, since it is a fact that men and women, whatever be their colour, can marry, and their offspring is always reproductive. The Negro and white female by their union produce mulattoes; mulattoes and mulattresses are reproductive, as are also their descendants—marriages between members of the red or brown races are fruitful, and, what is more, the fecundity of the descendants of mongrels is superior to that of men and women of the same colour.
Unless, therefore, we regard men as a solitary exception among all living beings, unless we withdraw them from the operation of the universal laws of nature, we must come to the conclusion that they do but form a certain number of races of one and the same species, and all descend from one primitive unique species.
Men are brothers in blood: this principle of universal fraternity imposed by nature, may