CORACIIFORMES, an order of birds comprising 14 fam ilies of doubtful mutual affinities, and including the oil-bird, frog mouths, kingfishers, rollers, bee-eaters, motmot, hoopoes; horn bills, nightjars, swifts and hummingbirds (qq.v.). In the most recent classifications, the oil-bird, frogmouths and nightjars are separated as the order Caprimulgi f ormes and the swifts and hum mingbirds as the order Micropodiformes. (See ORNITHOLOGY.)