Abstract
Genetical tests of translocations produced in Drosophila sperm by 5000 r units of X-rays at 220 KVP filtered with 1/2 mm. Cu and 1 mm. Al showed 117 translocations (17.2 [plus or minus] 1.46%) when the irradiation was applied at 167 r/min. and 136 translocations (17.0 [plus or minus] 1.33%) when applied at 12.5 r/ min.