Savage dances sometimes serve the purposes of courtship, and, of course, the wild intoxication of movement which they lead to is itself calculated to produce sexual excitement. Notes on obscene dances may be found in the works of Waitz-Gerland (Australian), Turner (Samoan), Ehrenreich (Brazilian), Powers (Californian), Fritsch (Zulu), and others. When such dances serve the purposes of courtship they are not uninteresting. When they consist of a wild _mêlée_ in which participators and spectators are thrown into a condition of ecstasy, the idea of discriminating choice on the part of the women is difficult to apply. There is, however, no such difficulty in the way of my theory that violent excitement is a necessary preliminary. I give two examples from the bird world: “The black-headed ibis of Patagonia, which is almost as large as a turkey, carries on a strange wild game in the evening. A whole flock seems to be suddenly crazed; sometimes they fly up in the air with startling suddenness, move about in a most erratic way, and as they near the ground start up again and so repeat the game, while the air for kilometres around vibrates with their harsh, metallic cries. Most ducks confine their play to mock battles on the water, but the beautiful whistling duck of the La Plata conducts them on the wing as well. From ten to twenty of them rise in the air until they appear like a tiny speck, or entirely disappear. At this great height they often remain for hours in one place, slowly separating and coming together again while the high, clear whistle of the male blends admirably with the female’s deeper, measured note, and when they approach they strike one another so powerfully with their wings that the sound, which is like hand-clapping, remains audible when the birds are out of sight.”[519] In cases where this sort of orgy, indulged in by flocks of birds, serves sexual purposes, as it probably often does, my theory proves to be more explanatory than Darwin’s, and the same may be said of our general dance with its direct appeal to such stimuli. It is much less likely that some of the dancers will single out special partners than that participant and spectators alike will be thrown into an ecstatic state in which all restraints are cast off.