Effect of the Removal of the Frontal Ganglion on the Development of the Gonads in Locusta migratoria L.

Abstract

THE complete cessation of growth and moulting which results from the removal of the frontal ganglion from nymphs of Locusta migratoria L. has already been reported¹. This effect was attributed to the failure of the release and/or production of neuro-secretory material from the endocrine system of the insect. Based largely on the work of Thomsen² and Strangeways-Dixon³, it was suggested that, in these operated animals too, protein metabolism was interfered with, or stopped. Highnam⁴ had shown that, in Schistocerca gregaria Forsk., cautery of the neuro-secretory cells prevented development of the terminal oocytes in the ovaries. It therefore seemed a useful check on our hypothesis to remove the frontal ganglion from fledgling male and female Locusta migratoria and to observe the results of this operation on the further development of the gonads.