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of the law being not merely to preserve the game, but to signalize the sanctity of this instinct.

The brooding instinct rises like a fever, reaches a culmination at the time the eggs hatch or shortly after, and then rapidly subsides. At the same time there is a corresponding depression of fear, which returns with the waning of the brooding impulse. Thereafter brooding becomes more intermittent, being determined in some degree by the intensity of light, and weather conditions, with the difference that fear is now in the ascendentascendant [sic], and the element of intelligence, at the plane of association at least, is not lacking. At its first manifestation it affords a beautiful illustration of a pure instinct, adapted to the preservation of the offspring, though attended at times by what blind and costly sacrifice of life can well be imagined.

At the command of the brooding instinct, or at the sight or touch of the eggs, and later of the young, the whole nature of the bird is quickly changed. In his experiments with noddy and sooty terns, Watson found that while neither bird recognized its own egg, the habits of a laying noddy could be almost immediately changed into those of a "sitter" by placing an egg in its nest. Before the appearance of the egg, this bird is shy and easily disturbed, but contact with an egg, and an artificial one at that, seemed to change its disposition