EVERY generation produces a number of young naturalists, some of whom seek a career in which they can follow their interests. Of these a proportion have in the past turned to entomology, and it is to be hoped that they will continue to do so in the future. The proceedings of a recent conference held in London, the Second International Congress of Plant Protection, and a remark in the presidential address to the Society of Chemical Industry1 tend to support the view—much fostered by interested parties at the present time—that entomology in its applied aspects is no longer the province of the biologist, but is rapidly becoming, if it has not already become, that of the chemist and physicist. Sir David Rivett, in the address referred to, said, “When for example one approaches a problem of pest insect control, may it not well be that a physicist, aided by a mathematician and guided by a chemist, will prove of more value than any other worker?"