While among the mammals this business of training is usually intentional and a family matter, attended to by the mother, with such invertebrates as bees and ants, in which the females are simply egg-laying machines, the mother's educational function is null, and the care of the young rests with the sterile workers. Yet the mental side of the maternal function subsists in mother ants in a latent state, and virgin females have been seen, according to Huber, busying themselves with the eggs and the larvæ. But as a rule the training in the nest is a grand social affair, committed to the female workers, who devote themselves with complete abnegation to their task, and seem to enjoy themselves in performing it. When the young have gone through their metamorphoses, their nurses, now become instructors, keep with them, guiding them through the labyrinth of the city in all its windings; and this education is probably carried much further than observers are able to follow it, for the working ants must be trained for their duties. Their industry is too complicated to be purely mechanical and blindly instinctive as is often supposed. But the observation of this training requires distinctions between individual ants which the human eye is hardly competent to make. Among the slaveholding ants the education consists largely in transforming certain inveterate tendencies. They make war upon another species, the brown ants, capture their young, and bring them up to be their own slaves, in ignorance of the species to which they belong, and of its traits. An equivalent to this transforming tendency of education may be found among the vertebrates, where, if we take the young early enough, we can disturb their hereditary functional manifestations to a considerable extent. Young chickens, raised apart, do not learn to drink by filling their beak and raising their head, but plunge their bill into the full vessel. Newborn babes soon lose the faculty of sucking if they are fed with the spoon.
All this is because, notwithstanding morphological differences, all living beings have something in common at the bottom; so that the physiological psychology of one species may illustrate that of others, and even of man. In short, we have good grounds for saying that all animals, whether vertebrates or not, but possessing nervous centers, however little developed, are susceptible of education; with all a suitable training long enough continued can to a certain extent derange the hereditary tendencies which we call instinctive, and even create new ones. These perturbations, these metamorphoses of native tendencies, are observable with special ease in domestic animals. We have a right to be surprised that, after having so successfully adapted the few animals with which we are acquainted to his service and use, man has not tamed many others. We may suppose
