Abstract
The life history of Onesia accepta Mall. is described. This species is parasitic on the earthworm Microscolex dubius Fletcher. The first and second larval instars are passed under the skin and the third instar in the body cavity of the host. The feeding period of the maggot is approximately 20 days, and the pupal stage about 12 days.The external morphology of the three larval instars and of the puparium is described in detail.