It need not be repeated that any race-mark is liable to deceive.
* * * * * We have sufficiently considered the use to which the particular race-mark of head-form has been put in the attempted classification of the very early men who have left their bones behind them.

Let us now turn to another race-mark, namely colour; because, though it may really be less satisfactory than others, for instance hair, that is the one to which ordinary people naturally turn when they seek to classify by races the present inhabitants of the earth.
When Linnaeus in pre-Darwinian days distinguished four varieties of man, the white European, the red American, the yellow Asiatic, and the black African, he did not dream of providing the basis of anything more than an artificial classification.

He probably would have agreed with Buffon in saying that in every case it was one and the same kind of man, only dyed differently by the different climates.

But the Darwinian is searching for a natural classification.

He wants to distinguish men according to their actual descent.