these conditions have facilitated the development of an ideal and æsthetic love-literature which never would have appeared, and cannot even be understood, among nations where this division does not exist. On the other hand, the same causes have, as it is needless to point out, produced a literature and an art which, by their deliberate grossness, stand in the strongest contrast not only to the romantic utterances of civilised nations, but even to the more naïve products of primitive tribes. We cannot in this connection do more than indicate these general views, the validity of which may be easily tested by the reader by application to modern art. Within the boundaries of ethnological art—that is, between the stages of evolution represented by Tierra del Fuego on one side and ancient Mexico at the other end—there can, however, be found sufficient proofs of the general law which manifests itself more fully in the richer and more highly differentiated products of modern art. Love, although fundamentally one and uniform as a feeling, is in its utterances ever changing with changing conditions of life. If its ground is biological, its nuances are always determined by sociological influences. Without taking into due account all these nuances it is impossible to assert anything about the influences of sexual selection on art. The considerations adduced in this chapter have led to results which, by their negative character, may seem to be very unsatisfactory. It was shown first of all that artistic activities, in so far as they emphasise the qualities of either sex, must necessarily exercise an attractive influence on the opposite sex. From a psychological point of view we tried to prove that the various forms of self-decoration, such as are to be met with among primitive tribes, must have been eminently effectual as means of such attraction. But we were, on the other hand, compelled to admit that the primary origin of dress and ornaments in many cases could be quite as well explained without any reference to the relation between the sexes. Thus it became necessary to examine closely the dramatic and poetic art for the purpose of ascertaining in which tribes competition for the favour of the opposite sex can be assumed as a cause of the art. The ethnological evidence, as quoted in the works on sexual selection, appeared too incomplete and inconsistent to admit of any general conclusions being drawn, and it seemed indispensable to sift the information as well as to classify the instances. Instead of one all-explaining principle, which could be applied in all the various cases, we were confronted by a multitude of causes and conditions, all of which needed to be investigated separately and weighed against each other. A reader who thinks every discussion fruitless which leads to no dogmatic conclusion might perhaps object that our re-examination of this much-debated question has utterly failed in its purposes. We may, however, be allowed to