Puparium Formation in Flies: Contraction to Puparium Induced by Ecdysone

Abstract
Larvae of the fly Calliphora erythrocephala (Meigen) were deprived surgically of their ring glands at an age prior to the appearance of ecdysone in the blood, and then injected with ecdysone. They contracted into the typical barrel-shaped puparium, before the onset of tanning. This proved that ecdysone controls the puparial contraction as well as tanning.