Westermarck recognizes at the same time that the preference given to virgins has also a biological basis in the instinctive masculine feeling of jealousy in regard to women who have had intercourse with other men, and especially in the erotic charm for men of the emotional state of shyness which accompanies virginity.

(This point has been dealt with in the discussion of Modesty in vol.i of these _Studies_.) It is scarcely necessary to add that the insistence on the virginity of brides is by no means confined, as A.B.Ellis seems to imply, to uncivilized peoples, nor is it necessary that wife-purchase should always accompany it.

The preference still persists, not only by virtue of its natural biological basis, but as a refinement and extension of the idea of woman as property, among those civilized peoples who, like ourselves, inherit a form of marriage to some extent based on wife-purchase.

Under such conditions a woman's chastity has an important social function to perform, being, as Mrs.Mona Caird has put it (_The Morality of Marriage_, 1897, p.

88), the watch-dog of man's property.