Summary
An investigation of the effects of exposing Drosophila melanogaster to γ-rays and α-particle radiation of low- and high-LET has resulted in dose-mean longevity curves of the exponential type. The effect of low-LET particles was similar to that of 60Co, whereas the high-LET α-particles were more effective than the two other types of radiation with an RBE of 1·3. No protective effect of low doses (3 and 5 krads) was observed. No dose-rate effect was observed in the range 4 to 256 krads/min.