Effects of Exogenous Moulting Hormones on Puparium Formation in Calliphora

Abstract

Pupal sclerotization in holometabolous insects has been widely used as a basis for bioassays of moulting hormone activity (for review see Horn 1969), anJ there has been considerable interest in the mode of action of these hormones at the cellular level (Karlson and Sekeris 1966). It is surprising that the effects of exogenous moulting hormone on the time and mode of puparium formation in the intact dipteran larva have seldom been reported (except e.g. Fourche 1967, on Dro8ophila), especially in view of interest in the relative biological activity of the various ecdysone-group steroids in stimulating sclerotization (Ohtaki, Milkman, and Williams 1967).