Ultraviolet light and puparial weight as factors in the autogeny of the fleshfly, Sarcophaga falculata

Light conditions and the puparial weight were assessed as factors that affect autogeny in Sarcophaga falculata. The frequency and degree of autogeny differed in flies originating from large or small puparia. The limitation of puparial weight range did not prevent the variation in the stage of autogeny. Autogeny was low in flies kept in complete darkness and was very high in uv irradiated flies. Removal of the ocelli before u.v. irradiation prevented most of the increase in autogeny, and it is assumed that the ocelli are the main transmitter of the u.v. effect on oögenesis. Neurosecretion was found within the cells of the ocellar nerve of adult flies. It is possible that this neurosecretion plays a rôle in the u.v. induced effect on autogeny.