Certain birds are not content alone with the display of natural ornament, but make use of further aesthetic appeal in the construction of their homes in a truly beautiful manner. Some species of humming-birds are said to decorate the exterior of their nests in great taste with lichens, feathers, etc. The bower-birds of Australia construct bowers on the ground, ornamented with shell, feathers, bones and leaves. Both sexes take part in the building of these abodes of love, which are used for the courting parades. But an even more delightful example of the rare sexual delicacy in courtship is recorded by M.O. Beccari of a bird of Paradise of New Guinea, the _Amblyornis inornata_.[81] "This wonderful and beautiful bird 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, so that the eye may be always agreeably flattered. These curious constructions are solid, lasting for several years, and probably serving for several birds." It is, I think, by such cases as these that we may come to realise the extraordinary power of sex-hunger. It seems to me that many of us are still walking in sleep; fear holds our eyes from the truth. But as we look back to the complex and often beautiful manifestations of love's actions among our animal ancestors, we begin to perceive that unanalysable something called "beauty," which is the glory that has arisen out of that first simple impelling hunger, which drove the male cell and the female cell to unite. This is how I see things--Life knows no development except through Love. II.--_Further Examples of Courtship, Marriage, and the Family among Birds_ It is especially upon the efflorescence of male beauty among birds that Darwin founded his celebrated theory of sexual selection. The motley of display seems endless, beautiful plumes, elongated feathery tresses, neck-ruffs, breast-shields, brightly-coloured cowls and wattles occur with marvellous richness of variety.