(the ankle-joint), open his wings, and then swing them
alternately backward and forward, as if on a pivot.... While
rolling, every feather over the whole body is on end, and the
plumes are open, like a large white fan. At such a time the bird
sees very imperfectly, if at all; in fact, he seems so
preoccupied that, if pursued, one may often approach unnoticed.
Just before rolling, a cock, especially if courting the hen, will
often run slowly and daintily on the points of his toes, with
neck slightly inflated, upright, and rigid, the tail
half-drooped, and all his body-feathers fluffed up; the wings
raised and expanded, the inside edges touching the sides of the
neck for nearly the whole of its length, and the plumes showing
separately, like an open fan. In no other attitude is the
splendid beauty of his plumage displayed to such advantage."
(S.C. Cronwright Schreiner, "The Ostrich," _Zoölogist_, March,
1897.)

As may be seen from the foregoing fairly typical examples, the
phenomena of courtship are highly developed, and have been most
carefully studied, in animals outside the mammal series. It may
seem a long leap from birds to man; yet, as will be seen, the
phenomena among primitive human peoples, if not, indeed, among
many civilized peoples also, closely resemble those found among
birds, though, unfortunately, they have not usually been so
carefully studied.

In Australia, where dancing is carried to a high pitch of
elaboration, its association with the sexual impulse is close and
unmistakable. Thus, Mr. Samuel Gason (of whom it has been said
that "no man living has been more among blacks or knows more of