The virile hum of honey-and carpenter-bees descends from the flowery summits to the listener beneath, the contented music of a race dwelling overhead and nearer the skies than we. It is such an apple--Baldwin, pippin, or russet--gnarled and archaic in trunk and a bower of beauty above, which becomes the home-tree of that feathered gnome, the house-wren, a sprightly elf, living in the depths of a tree trunk and yet full to the brim of song. He may derive of the flowing sap some genial trait and takes to the apple as a swift to the chimney, or a redwing to the swamp. After the cold rains of late May have taken off the blossoms and with them the bees, the place becomes melodious with his song. It is thenceforth his estate, and he dominates it with his small personality. With him his house is his castle, and in true medieval fashion he barricades his door. Within is snug enough, but without it has a feudal and forbidding look,--a formidable barrier of twigs, erected perhaps against the house-sparrow or for fear the robber-owl may peer too closely. In this choice of a building site the bird reveals something of itself. Contrast the wren with the phoebe, a cliff-dweller, loving the contact of the ledge itself better than any bush or tree. The song-sparrow has an eye for the wild rose and the yellow warbler for apple blossoms, but the phoebe has some austere traits which make the stern rock more congenial to her. Some birds are architects, others builders merely. The vireos are a family of artists, whereas the improvident cuckoo will not even lay a proper floor to her nest. A look into some nests is a glance at the domestic life of a savage people, and yet we find the virtues we most esteem--patience, perseverance and fortitude. Hour in and hour out the faithful kingfisher flies from the nest to the fishing-ground, bringing each time a small fish. He is a primitive and industrious fisherman who gets an honest living by his skill and supports his family, yet he is under ban, while the dilettante whips the stream for his pleasure. The hoarse rattle of the kingfisher is an altogether barbarous chant with which he beguiles himself as with a hunting song. His is an austere temperament with no room for melody. But that he returns every year to the same nest--the ancestral hall--is evidence of some more domestic and kindly trait in his character. This nest is an excavation in the sand, high in a bluff, and is perhaps five feet deep,--a true cave, and its inmate a cave-dweller. We have thus both cave-and cliff-dwellers among us--primitive states of man still exemplified by birds. The cave-dweller had something in common with the kingfisher, which led him to burrow in the earth for a home.