That “one touch of Nature which makes the whole World kin” is surely nowhere more obvious than in the “Courtship” of Animals. For the “Beasts that Perish,” no less than Man himself, are stirred by the same emotions; the Fever of Love runs as high in them as in ourselves; and its modes of expression are not so different, though they may superficially appear to be so. The nature of these differences and their interpretation, it is the purpose of this book to set forth.

Charles Darwin laid the foundation for the study of this phase of Animal behaviour in his masterly work on the “Descent of Man,” a work which has been much criticized and much misunderstood since Carlyle’s crude abuse of it as the “Gospel of Dirt.” Darwin was the first to show us that the fierce battles, and strange antics, which characterize so many of the “Lower Orders of Creation” under the exaltation of the Sexual emotions are manifestations fraught with tremendous consequences to the race.

The facts which he brought to light, and the discussions to which they have given rise, have, however, unfortunately been too commonly regarded as merely interesting to those who have a liking for Natural History.

This is a most unfortunate mistake. For such facts have a vitally important bearing on the very problems of social well-being which now loom so largely among us. “Reform” is in the air. Its protagonists are busy amongst us with schemes for our regeneration, among which “Sex-problems” are made to occupy a very conspicuous place. But no good can come of their cogitations so long as they fail to realize the springs of behaviour in this regard. The facts herein set down will, it is hoped, help much towards this end.