s is especially the case with birds.
Among the higher mammals polygamy is most common, but permanent unions
are formed, especially among the anthropoid apes. Thus strictly
monogamous marriages are frequent among gorillas and orang-utans, the
young sometimes remaining with their parents to the age of six years,
while any approach to loose behaviour on the part of the wife is
severely punished by the husband.[50] We find both the matriarchate
and patriarchate family; and we may observe the greatest difference in
the conduct of the parents in their care of offspring. Even a rapid
examination of these customs is worth while, for they cast forward
many suggestions on our sexual, domestic, and social relationships.

Let us take first the phenomena of courtship.

It is possible to give only the briefest outline of this fascinating
subject. We will begin with the law-of-battle. Courtship without
combat is rare among mammals; it is less common in many species of
birds. Special offensive and defensive weapons for use in these
love-fights are found; such are the larger canine teeth of many male
mammals, the antlers of stags, the tusks of elephants, the horns of
antelopes, goats, oxen and other animals, while among birds the spurs
of the cock and allied species are examples of sexual weapons.[51]

"The season of love is the season of battle," says Darwin. To those
who understand love there will be no cause of surprise in these
procreative explosions. There can be no doubt that such combats are a
stimulus to mutual sexual excitement in the males who take part in
them and the female who watches them. Throughout Nature love only
reaches its goal after tremendous expenditure of energy. Courtship is
the prelude to love. The question is--what form it shall take? It is
this that even yet we have not decided. But the importance of
courtship cannot be overlooked. We must regard it as the servant of
the Life-force. In the fine saying of Professor Lloyd Morgan,[52] "the
purpose of courtship reveals itself as the strong and steady bending
of the bow, that the arrow may find its mark in a biological end of
the highest importance in the survival of a healthy and vigorous
race."

Even the most timid animals will fight desperately under the stimulus
of sex-passion. Hares and moles battle to the death in some cases;
squirrels and beavers wound each other severely. Seals grapple with
tooth and claw; bulls, deer and stallions have violent encount