To resume, monogamy is by far the most widespread form of marriage. This is explained by the relative number of men to women. It has often been stated that the number of individuals of the two sexes is nearly the same, and this has been used as an argument in favor of monogamy. But this statement is incorrect; sometimes it is the men, but more often the women, who predominate. Among the natives of Oregon there are seven hundred men to eleven hundred and eighty-five women. Among the Punkas and other races the number of women is two or three times greater than that of the men. In Kotcha-Hamba there is only one man to five women. Among other races there are, on the contrary, more men than women, especially in Australia, Tasmania, and Hayti. In the latter island there is only one woman to five men. In Cashmere there are three men to one woman. Among the negroes, on the contrary, the women predominate, sometimes in the proportion of three to one, but more generally as three to two. In Europe, more boys than girls are born on the average, but from the age of fifteen to twenty the numbers become equal, and after twenty the women predominate. This is due to the greater mortality among men, owing to war, the greater danger of masculine occupations, and also to alcoholism. In the fifteen largest towns in Switzerland alcoholism is the direct or indirect cause of death in 10.5 per cent. of men above the age of twenty. Among savages the women often take part in war, for instance the Amazons of Dahomey. Drinking habits are also the same or absent in both sexes, which equalizes matters. When the men predominate in these people, this is often due to infanticide committed on young girls, and also to overwork of the women. With the Cingalese the natality of boys is greater than that of girls, while in Asia Minor two girls, in Arabia even four girls, are born to one boy. The Arab says, "Allah has given us more women than men; it is, therefore, clear that polygamy is a divine commandment." =Production of Sexes at Will.=--I will say a few words on the question of the causes of production of the sexes. There is no want of hypotheses, assertions, nor even of experiments on this subject; but, we are obliged to admit that up to the present we know nothing certain. No one has yet succeeded in producing experimentally in animals males or females at will. According to one theory, which has created much impression, overfeeding produces females and underfeeding males. Although this appears to be true in certain cases among some animals, it is in no way proved in a positive manner.