man's presence, exhibit, after a single generation, all the traits of their wild congeners, including extreme dislike and dread of man. On the other hand, many wild animals, especially those who have a minimum of instinct of inborn mental traits, and a maximum of reason, of acquired mental traits, such as monkeys, ichneumons, parrots, jackdaws, &c., exhibit in the first generation of captivity as thorough a subjection to man as the species longest domesticated, especially if during growth, and even during adult life, they are allowed no commerce with, and so can acquire no traits from, the wild members of the same species.
As regards man also, the inborn variations caused in him by "centuries of civilization" can only be such as are due to Natural Selection, acting under somewhat changed conditions. These, as will be seen, are often very important physically, but much less important mentally. It will be found that civilized man differs mentally from savage man almost exclusively in acquired traits, the difference in inborn traits being practically inappreciable, except in one instance, which, however, is of capital importance.
