As the advantages of neighbourliness dawned upon these children of nature, rules and regulations, for the control of the individual on behalf of the good order of the community, came into being; and among the earliest laws to be framed, we may be certain, were those for the regulation of marriage. These, as we may gather from the history of savage races to-day, did not concern themselves with chastity, at any rate before marriage, it was enough if they secured the right of possession, and excluded the dangers of close intermarriage. Promiscuity in the past was never the practice of any race, its existence to-day, among both savage and civilized people, is due in part to imperfections in the social scheme, and in part to the vagaries of individuals. That the sexual instincts form the bed-rock on which depends the survival of all races of animals, which, for their propagation, require the co-operation of separate sexes, is beyond dispute. And it is no less certain that in so far as the evolution of man is concerned, jealousy has been a powerful integrating factor. Among the higher animals apart from Man, both polygamy and polyandry are met with, and this with no apparent detriment to the race. It is significant, however, that polyandry is never met with among the mammals, and but rarely among the birds, when, as will be shown, this form of sexual relationship has been accompanied by a profound modification of the behaviour of the sexes in regard, not only to courtship, but to the offspring. The male has lost his masculinity, and the female her femininity. In human society both forms of marriage prevail, and there can be no doubt, from the history of such customs, that of the two types, polygamy is much to be preferred. It is certain that no race which practices polyandry can do more than hold its own, and that in a low grade of development. This cannot be said of polygamy, which might indeed be commended as a solution of some of our own social problems, were it not almost certain that the remedy would prove as bad as the disease.