Certain birds are not content with their natural ornaments, however brilliant these may be, but give the rein to their æsthetic desire in a way that may be called human. Mr. Gould assures us that some species of humming-birds decorate the exterior of their nests with exquisite taste, making use of lichens, feathers, etc. The bower-birds of Australia (_Chlamydera maculata_, etc.) construct bowers on the ground, ornamented with feathers, shells, bones, and leaves. These bowers are intended to shelter the courting parades, and both males and females join in building them, though the former are more zealous in the work.[15] But in this erotic architecture the palm is carried off by a bird of New Guinea, the _Amblyornis inornata_, made known to us by M. O. Beccari.[16] This bird of rare beauty, for it is a bird of Paradise, constructs a little conical hut to protect his amours, and in front of this he arranges a lawn, carpeted with moss, the greenness of which he relieves by scattering on it various bright-coloured objects, such as berries, grains, flowers, pebbles, and shells. More than this, when the flowers are faded, he takes great care to replace them by fresh ones, so that the eye may be always agreeably flattered. These curious constructions are solid, lasting for several years, and probably serving for several birds. What we know of sexual unions among the lower human races suffices to show how much these birds excel men in sexual delicacy. Every one is aware that the melodious voice of many male birds furnishes them with a powerful means of seduction. Every spring our nightingales figure in true lyric tournaments. Magpies, who are ill-endowed from a musical point of view, endeavour to make up for this organic imperfection by rapping on a dry and sonorous branch, not only to call the female, but also to charm her; we may say, in fact, that they perform instrumental music. Another bird, the male of the weaver-bird, builds an abode of pleasure for himself, where he goes to sing to his companion.[17] Audubon has made one observation in regard to Canadian geese which is in every point applicable to the human species. The older the birds are, he says, the more they abridge the preliminaries of their amours. Their poetic and æsthetic sense has become blunted, and they go straight to their object.