joins male and female is an instinct developed through ... natural selection" (p. 20). This is not the sexual instinct, for among animals, and quite probably also with primitive man, that instinct is powerful only at certain seasons of the year. Nor is it the social or gregarious instinct, for the anthropoid apes and lowest savages seem to live in families rather than in larger associations, and the scantiness of food probably compels this. It is rather the parental instinct, whereby the male is induced to co-operate with the female in aiding the offspring to survive. "Marriage is therefore rooted in family rather than family in marriage" (p. 22). Marriage exists among the higher monkeys and "human marriage appears to be an inheritance from some ape-like progenitor" (p. 50). Its development is connected with the decrease in the number of offspring and the lengthening of the period of infancy. The position thus reached is very ably maintained (pp. 51-133) against the many advocates of the opinion that "man lived originally in a state of promiscuity" and the conclusion reached that "there is not a shred of genuine evidence that promiscuity ever formed a general stage in the social history of mankind" (p. 133).
Proceeding to treat of courtship and the means of attraction he thinks it "beyond doubt that men and women began to ornament, mutilate, paint, and tattoo themselves chiefly in order to make themselves attractive to the opposite sex" (p. 172). Dress probably originated in the same way, perhaps aided by the need of protection but not by a regard for decency. "It is not the feeling of shame that has provoked the covering, but the covering that has provoked the feeling of shame" (p. 208).
Among mankind marriage is prohibited between near kin and often between widely different races. On the analogy of the antipathy existing between different species of animals, the latter is explained as based on an instinctive recognition of the commonly increased sterility of hybrids, while the prohibition of marriage between near kin is believed to find its source in the fact that a certain amount of difference between male and female is beneficial to the offspring. Hence an instinctive antipathy to incest has been fostered by natural selection, but the basis on which the instinct works is not kinship by blood but living under the same roof. Where remote relatives live together, the list of prohibited degrees is longer. Hence the basis of exogamy and of the classificatory system of relationship is largely the living together of many kinsfolk between whom marriage comes to be prohibited.
Dr. Westermarck is inclined to accept the theory that "organisms when unusally well nourished produce comparatively more female offspring; in the opposite case more male" (p. 471), and to explain polyandry as due to the scarcity of women in very poor countries. He concludes
