3 main periods of imaginal development: juvenility, reproduction, ageing, were established in Acheta domestica and characterized by morphological and functional features of some organs (integument, wings, fat body, wing muscles, ovaries, and body proportions). Allatectomized crickets remain in the first period up till the day of death; this allowed to suggest that the hormone of corpora allata in imago controls the normal correlated development of different organs and tissues and ensures the transition to subsequent periods of imaginal ontogenesis. In allatectomized crickets of both the sexes, the duration of imaginal life is markedly longer and the fecundity of females is much lower. It is suggested that the hormone of corpora allata controls the life span and the fecundity independently.