Moult inhibition in the insectDysdercus cingulatus (Insecta: Heteroptera) by the cerebral glands of the millipedeJonespeltis splendidus (Myriapoda,Diplopoda)

Summary Implantation of 2 pairs of cerebral glands of the diplopodJonespeltis into the newly-moulted 4th or 5th instar nymphs of the insectDysdercus delayed the moulting of these insects for a fairly long time. Implantation of cerebral glands into 1-day old 5th instars postponed the subsequent moult for a shorter period, whereas implantation of cerebral glands into 2-day old 5th instars had no effect. These observations suggested that a neurosecretory factor from the cerebral glands inhibited moulting in this insect, and in the case of 5th instar nymphs there was a critical period before which implanted glands were effective in moult inhibition.Acknowledgments. Prof. V.K.K. Prabhu is thanked for suggesting the topic and for guidance. The University of Kerala is thanked for the fellowship awarded. The laboratory facilities afforded are also gratefully acknowledged.