The explosive increase in the world's human population, with conse- quent need to feed an ever-increasing number of hungry mouths, and the largely resultant disturbances and pollution of the environment in which man must live and produce the things he needs, are forcing him to search for means of solving the first problem without intensifying the latter. Food production requires adequate assurance against the ravages of insects. In the last three decades short-sighted, unilateral and almost exclusive employment of synthesized chemicals for insect pest control has posed an enormous and as yet...