* Abbot, C. G., “Solar Radiation,” Proceedings of the Ohio State Educational Conference, 11th annual session, April, 1931. Ohio State University Bulletin, Vol. 36, No. 3, pp. 412–414, Sept. 15, 1931, Columbus Ohio. See also, Smithsonian Institution Report, 1930: Report of the Division of Radiation and Organisms, pp. 11–12; New Researches on the Effect of Light Waves on the growth of plants, by F. S. Brackett and E. S. Johnson, pp. 255–265.