“Because of its wide-open eyes the nocturnal bird of prey needs a subdued light like that of early dawn and of evening dusk. It is, therefore, at nightfall and at the first signs of daybreak that these birds leave their retreats and seek their prey. At these hours their hunt is a fruitful one, for they find the rats and mice, whether those that lurk about our houses and barns or those that live in the field, either fast asleep or on the point of going to sleep. Moonlight nights are the most favorable for the nocturnal bird’s purposes. Such nights are nights of plenty, affording opportunity for protracted hunting and many captures. “Let us follow the owl on its nocturnal expedition. The moment is propitious, the air is calm, the moon shines. The bird leaves its sylvan retreat; it skims over the open field, the meadow, the prairie; it inspects the furrows where the field-mouse lurks, the long grass where it burrows, the ruins of deserted buildings where both rats and mice scamper about. “Its flight is noiseless, its silent wing cleaving the air without the faintest sound. It is careful not to give the alarm to its destined victims. This noiseless flight it owes to the structure of its feathers, which are silky and finely divided. Nothing betrays its sudden coming, and the prey is seized without even suspecting the enemy’s presence. An extraordinarily keen sense of hearing, on the other hand, advises the bird of all that is going on in the neighborhood. Its ears, large and deep, perceive the mere rustle of a field-mouse in the grass. “The prey is seized with two strong claws warmly clothed in feathers clear down to the very nails. Each foot has four toes, of which three ordinarily point forward, and one backward; but, by a privilege common to nocturnal birds of prey, one of the anterior toes is movable and can point backward, so that the claw becomes divided into two pairs of equally powerful grippers when the bird wishes to seize, as in a vise, the branch whereon it perches or the victim struggling to escape. “A blow of the beak breaks the head of the captured rat. This beak is short and hooked, and the two mandibles have great mobility, which enables them, in striking against each other, to make a rapid clacking, a demonstration by which the bird expresses anger or alarm. “The mandibles open wide in the act of swallowing, revealing a mouth of ample proportions and a throat of excessive width. The prey, which has first been well kneaded by the claws, disappears down this throat, bones and all. Nothing is left of the rat or the mouse, not even the fur.