Apparent gradations in colour are occasionally observed among different members of one and the same tribe. As with ourselves, circulatory disorders are not absent among the aborigines, and such materially affect the quality of colour in the aboriginal’s skin. Simple anaemia, or even a temporary blanching of the tissues, through nervousness or fright during the time of an examination, will affect the appearance of the skin. In the same way, full-bloodedness, or a passing flush, will deepen the shade, the injection of blood into the underlying tissues being clearly noticeable through the epidermis. Pathological conditions like jaundice are also frequently developed in the aborigines, and impart to their skin a sickly ashen hue; in this case the yellow colour of the conjunctiva usually indicates the disorder. The likelihood of any such conditions being present should be carefully investigated before applying the standard colour tables of modern anthropologists.
The oldest systems of colour-classification divided the races of man into five groups—the white, the yellow, the red, the brown, and the black. But nowadays, even the layman knows that such hard and fast divisions are impossible. We find that among individuals of one particular race, whatever its so-called, and somewhat arbitrary, colour might be, there exist noticeable variations in shade. Red Indians have yellow or brown skins almost as frequently as a genuine red; the “white” races of Europe often have so dark a “complexion” that they are in reality brown; and the skin of a negro at times has a distinctly reddish or brownish hue.
Early anthropologists thought that the “dust or tawny” colour was due to the accumulation of carbon in the external layers of the integument. But since the introduction of the microscope, which made the study of thin sections of human skin under great magnification possible, it was found that the colour is due to living cells, which carry pigment in their protoplasm, and are more or less migratory.
In the Australian aboriginal, these pigment-cells lie quite superficially in the skin. Some years ago Professor Klaatsch, of Heidelberg University, when in Australia, managed to obtain the corpse of an aboriginal, which he consigned to a large tank holding an ordinary preserving fluid. Hermetically sealing the lid of the tank, the Professor shipped the specimen to Europe, where it was to be dissected. Some months later, I joined him at Breslau University, and together we opened the tank. Imagine our surprise when we beheld what one might describe as an anthropological contradiction—a “white blackfellow!” It took us some time to recognize in the form in front of us that of the aboriginal we had seen in Australia. What had happened was that, during the continued movement of the preserving solution during the transport, the superficial layers of the skin had been removed, and, with them, the colour too. In other parts, the skin had blistered and become detached, leaving more or less adherent strips of epidermis in which the colouring matter could be recognized.
I have seen a similar condition of things in corpses of aborigines, in the remoter districts of the Australian bush, where the dead are placed to rest on artificial platforms in the branches of trees. When, during the processes of decomposition, the skin peels off, and is washed away by the rain, the corpse assumes a pinkish white colour, resembling the body of a white man, some time dead. No doubt it was on this account that, in the early days of European settlement, it was a general belief among the aborigines that the white man was one of their own dead warriors returned to life in a different colour. We have a classical example in the experience of the escaped convict, William Buckley, who lived for thirty-two years among the natives of Victoria, the latter regarding him as their dead chief returned to life transformed. It is quite possible that this belief, which is so common among the tribes, originated from the fact that the natives themselves had observed, as Professor Klaatsch and I did, that the decomposing bodies of their dead might, under certain conditions, become very much lighter in colour.
Throughout the Northern Kimberley district the natives maintain that a dead tribesman will “jump up all-the-same whitefellow” in colour.
A singular case, illustrative of the shallowness of pigmentation in the epithelium of an aboriginal’s skin, was reported from Canowie Sheep Station by the late Rev. Tenison Woods. A native, suffering from an obstinate skin disease, was “dipped,” like a sheep, in a solution containing soft soap, tobacco, and arsenic, the last-named in the proportion of one ounce to the gallon of water. The native became very ill, lost his hair, and his finger and toe-nails. Eventually he became better, but his skin peeled off. He was then described as “presenting the appearance of a magpie during the time the process of decortication was going on.” Finally his skin became “smooth and as glossy as marble.”
In pemphigoid skin-eruptions, when blister-like bullae develop over different parts of the body, the lesions left in the skin for a while are pinkish and unpigmented. Scars resulting from a cut or burn remain red for a considerable time, but eventually turn the same uniform colour as the rest of the skin.
Under normal conditions, one may often find patches of pigment on mucous surfaces of the inner lips and mouth. The pathological condition known as leucoderma is, on the other hand, rather frequently observed among the different tribes of Australia. I have seen natives, both in the north and south of this continent, whose skin over certain areas was devoid of pigment; the hands and feet seem particularly prone to be thus affected.