X and neo-Y Mechanism of Sex-Determination in the Grasshopper, Thisiocetrus pulcher

Abstract

A NUMBER of instances of X and neo-Y mechanism of sex-determination is now on record in the Acrididæ¹. The purpose of the present communication is to record a further case found in the grasshopper, Thisiocetrus pulcher of the subfamily Catantopinæ, collected in the area adjoining the Biology Departments of the University of Calcutta. Only two male individuals could be found, on two separate occasions, in spite of extensive search. The observations reported here, therefore, are from sectioned preparations of the testes of the first, and Feulgen squash preparations of the testes of the second, specimen. A large number of dividing cells was obtained in both of them, which enabled us to study the behaviour of the sex chromosome complex during spermatogenesis.