Acclimatisation, strictly, the gradual adaptation of plants or animals to climates differing from those they have originally endured and at first injurious to them. The term is often confounded with domestication, the cultivation, that is, of foreign species that need not even be hardy: and with naturalization, the running wild of a hardy exotic species that may have come from a similar climate and not have required any adaptation. Acclimatisation may be brought about in the lifetime of an individual by its gradual transfer or by the physiological effects of the climate; but this can probably seldom effect much. It is more likely to succeed by transporting a considerable number of healthy adult individuals to some intermediate station and breeding from them, with careful selection of their hardiest offspring. Little has as yet been done in this direction. There are a good many Acclimatisation Societies in existence, of which perhaps the best known is the Paris Societe d'Acclimatation.