Influence of procaine HCl on larval development, adult lifespan and acid phosphatase activity in Musca domestica L

By treating larvae of Musca domestica L. with 4 x 10(-4%) procaine HCl we could shorten larval development, decrease larval mortality and increase number of adult offspring. A high concentration of procaine HCl (0.4%) caused a prolongation of the larval development, a lower pupal weight and a decreased number of adult offspring, which are, in our opinion, indications of a toxic effect. The effects of procaine HCl on ageing and acid phosphatase activity are not so clear. The distribution of subpopulations in a population and the correlation with acid phosphatase activity during adult lifespan are discussed.