Susceptibility of Seventy Species of Flowering Plants to X-radiation.

Ten years of study of the effects of x-rays on different species of flowering plants has resulted in a grouping according to ray susceptibility which should be of value, since many investigators are engaged in studying the various ways in which radiation influences living organisms. When sufficient data concerning the morphological and physiological action of x-rays have been collected, it should be possible to give reasons for the ray resistance of some families as compared with the ray susceptibility of others. This paper deals particularly with the morphological effects produced on the above-ground parts of seventy different species distributed in thirty-five families; another paper (11) will discuss the action of the rays on underground stems or roots of twenty-two species. The susceptibility of species of Helianthus, Solanumi, Lycopersicumn, Vicia, Atriplex, Linunt, Nernophila, and Zinnia have been treated elsewhere (5, 6, 7, 8, 9, 10, 12).