Hummingbirds have been truly called "Winged Gems." They are the smallest of birds, the usual plumage being a metallic green with throat or crown patches of the brightest of iridescent shining red, orange, blue or violet. Their nests are marvels of architecture being compactly and intricately made of plant fibres and downy feathers ornamented in some cases with lichens. Their flight is accompanied by a peculiar buzzing sound produced by their rapidly vibrating stiffened wing feathers. Their food is small insects and honey both of which they get chiefly from flowers.