Post-larval development of two rhythmical behavioural patterns: flight and song in the grasshopper, Omocestus viridulusS*

The ontogeny of two rhythmical outputs, wing-beat in flight and leg stroke in stridulation, was followed during post-larval development of the grasshopper 0.viridulus, The wing-beat frequency increases by a factor of c. 2; the repetition rate of the leg strokes remains constant. These results are discussed with respect to a hypothesis of neuronal economy within the CNS, and their biological significance.