Some throats that have apparently the same structure as far as the scalpel and microscope can distinguish have marvelously different powers of delivery. MacGillivray has pointed out that the Rook and the Hooded Crow seem to have just as complex an apparatus for their sepulchral utterances as the Nightingale and the Blackbird. But where loudness of sound is required without regard to range and quality there are some notable conformations, as in the Whooping Crane and the Howling Monkey. This Monkey has large cavities communicating with the glottis, and the air reverberates as it passes the larynx so the most deafening noises are produced. Birds sing and other animals yell, roar, and snort, not for love-making purposes, but rather because of the joy of life that is in these creatures, and it manifests itself in this way as well as in the gambols of the Lambkin or the antics of the Monkey. The voice of the Mule is the sweetest sound in the world--to some other Mule. But it is sweeter still to the Mule that makes the joyful sound. Placzeck notes that a bird frequently sings lustily when he knows himself to be entirely alone. "In the spring-time of love, when all life is invigorated, and the effort to win a mate by ardent wooing is crowned with the joy of triumph, the song reaches its highest perfection. But the male bird also sings to entertain his mate during the arduous nest-building and hatching, to cheer the young and, if he be a domesticated bird, to give pleasure to his lord and the Providence that takes care of him, and in doing so to please himself. Lastly, the bird sings--by habit, as we call it--because the tendency is innate in the organs of song to exercise themselves." In other words, animals have the apparatus for making noises provided them in their organs of breathing, and because they have them they use them and are delighted with them, each in his own kind. Finding them a source of joy unto themselves it is not to be wondered at that they employ their voices in their love-making because they feel that what pleases themselves so much must not be without effect upon their loved ones. [Illustration: AFRICAN LION. Copyright 1898, by Woodruff and Staley.] THE AFRICAN LION. Amid the far-off hills, With eye of fire, and shaggy mane upreared, The sleeping Lion in his den sprang up; Listened awhile--then laid his monstrous mouth Close to the floor, and breathed hot roarings out In fierce reply. --EDWIN ATHERSTONE. (1821)