The above stated results of experiments may be summed up in following statements: 1. The germination of air-dried seeds and of steeped seeds was accelerated by the irradiation of X-rays. 2. The acceleration of germination is obviously shown in the seeds X-rayed in the air-dried condition, and the dose of 5H-10H seemed to be an optimum. 10H especially showed an evident acceleration of germination (refer to Germination Table 3). 3. In the further growth after germination, pants grown from the seeds irradiated after 12 hours' steeping were worse than plants grownfrom the seeds X-rayed in the air-dried condition. In the latter case, between the state of growth of the controls and that of X-rayed material there appeared no great difference. But in the former case the irradiated showed the better growth in an earlier stage. 4. In the case of steeped-irradiated material, 15H seedlings generally grew well. The 5H, 7H and 10H seedlings were poorer in growth than the controls at the time of germination, but in the further growth stages surpassed them. 5. The acceleration of germination varies with the current (in the case of the same material and the same hour of exposure) and the hour of irradiation (in the case of the same material and under the same current) in a definite tube.