Abstract
As a result of several years work in the Anglo-Egyptian Sudan (Maxwell-Darling, 1934, 1936, 1936 a), it was concluded that the only outbreak centres of the Desert locust in north-eastern Africa were on the Red Sea coast. It appeared probable, however, that there existed other outbreak centres in Arabia, and unless those could be discovered and controlled, an outbreak originating in Arabia would spread into Africa and the Near East.