Imms' General Textbook Of Entomology : Volume I: Structure, Physiology And Development

A single pair of antennae (homologous with the anten- nules of the Crustacea) is present and the head also bears a pair of mandibles and two pairs of maxillae, the second pair fused medially to form the labium. The thorax carries three pairs of legs and usually one or two pairs of wings.