pheric conditions. (3) The rate of removal of Sr* from the stratosphere corresponds to 20 per cent per year or faster. In concluding, we want to repeat that this has been our interpretation of the data. The AEC is collecting information that, it is hoped, will eventually eliminate differences of opinion. Although everyone wants to obtain the best picture of fallout phenomenology, it should be emphasized that the differences in the physical aspects of fallout are still much smaller than the biological aspects. 338