Comparison of frequency patterns between whole-body and fractional mutations induced by X-rays in Drosophila melanogaster: E. Inagaki and Y. Nakao, Mutation Res., 3 (1966) 268–272. Page 269, lines 4 and 5 under Table I should read: “decrease with increasing dose in the ranges employed, i.e., 1.0 (6/6) at 1000 R, 0.38 (5/13) at 2000 R, 0.20 (6/30) at 3000 R, and 0.16 (3/19) at 4000 R.”