The incoming of the Glacial epoch does not appear to have been accompanied by any acclimatization of the plants - the species belonging to temperate Europe were locally exterminated, and Arctic forms took their places.
But in most cases habit, however prolonged, appears to have little effect on the constitution of the individual, and the fact has no doubt led to the opinion that acclimatization is impossible.
The acclimatization of white men in tropical Africa generally is dependent largely on the successful treatment of tropical diseases.
In order, therefore, to have the best chance of acclimatizing any animal or plant in a climate very dissimilar from that of its native country, and in which it has been proved that the species in question cannot live and maintain itself without acclimatization, we must adopt some such plan as the following: i.
It has been recommended by C. Darwin, and at one of the early meetings of the Societe Zoologique d'Acclimatation, at Paris, Isodore Geoffroy St Hilaire insisted that it was the only method by which acclimatization was possible.