[Biological activity of precozen I on Musca domestica and Aedes aegypti]

Paper presents the results of the study of biological effect of precozen I--preparation with antijuvenile type of action on flies and mosquitoes. Parenteral administration resulted in reduced rate of imago hatching, alterations in female reproductive system, hereditary sterility. Treatment of flies' as well as mosquitoes' larvae caused various moult alterations: prologation of development stages, reduced chitinization. Multiple effects of precozen I on insects, characteristic both of hormonal preparations and chemosterilants, were observed.