Virus Diseases of Plants

AN interesting discussion upon "Virus Diseases of Plants"was held during the meeting of the British Association at Liverpool between the Sections of Botany and Agriculture. These obscure maladies, which are of great economic importance, affect a great variety of cultivated plants and have lately received much attention from plant patho-logists. Formerly these diseases were attributed to general physiological degradation, notably in the potato, but since they have been shown to be markedly infectious, they are usually considered to be caused by organisms of ultramicroscopic size, which are disseminated largely by means of insects.