Phases of Locusts and their Interrelations

The theory of phases of locusts put forward as a working hypothesis by the senior author (Uvarov, 1921) has led, as might have been expected, to further researches in that direction, but the results obtained have been in some cases apparently contradictory. A summary of the work done on these phases has been published recently in a book (Uvarov, 1928), and we do not propose to repeat it here, the purpose of the present joint paper being to discuss very briefly certain aspects of the problem in the light of new observations made by Predtechensky (1928) in Russia and by the junior author in Madagascar.