Secretion of Juvenile Hormone by the Corpus Allatum of Calliphora

Abstract

IT is now generally accepted that metamorphosis in insects is prevented throughout the larval stages by the secretion of the ‘juvenile hormone’ by the corpus allatum; but this has never been quite satisfactorily proved in the Diptera. Vogt¹ obtained some evidence that the corpus allatum restrains the development of the imaginal disks in the early stages of Drosophila, She also showed² that the corpus allatum of young Drosophila larvæ would induce yolk formation in adult Drosophila deprived of the corpus allatum ; and since the yolk-forming hormone is the same as the juvenile hormone³, this finding suggests that the hormone is present in the Drosophila larva. Vogt⁴ and Possompès⁵ also obtained evidence that the corpus allatum of the adult Drosophila and Calliphorawill cause partial and local inhibition in the formation of pupal or adult cuticle.