J.G. NEEDHAM & M.J. WESTFALL (1975, A manual of the dragonflies of North America, Univ. California Press, Berkeley-Los Angeles-London) classified the larvae of Anisoptera into three groups according to their haunts and habitats; climbers, sprawlers and burrowers. Among the climbers we can count the Aeshnidae and the Libellulidae. Their larvae can live swimming in open spaces, moving about and hunting among the waterweeds and underwater roots. Their legs are their main help in this kind of locomotion. The abdomen of the Aeshnidae is long, dorsally convex and flat-bottomed. In captivity lateral waving and vertical movements of the abdomen can easily be observed. These movements can also be seen when we hold and compress the larva of e.g. Anax imperator. The insect is even capable of setting intself free by movements of its abdomen.