author, on the basis of theoretical considera- 

 tions, refuses to acknowledge the action of this 

 physical factor on the development of plants, 

 then, upon getting positive results he ascribes 

 them to chance. That is what Seide did in his 

 experiments (1929)* with the ova of Ascaris 

 megalocephala . Observing in one experiment 

 an increase of 26% (as compared to the control) 

 in dividing irradiated ova, and failing to obtain 

 similar results upon repetition of the experi- 

 ment, he calmly proceeded to reject the first 

 experiment as "due to chance, " instead of 

 determining why the second experiment did not 

 succeed. Johnson [1931] acted in the same 

 way. Observing an increase in the green weight 

 of the plant after irradiating sunberry seedlings, 

 she assumed that it was due to chance and 

 deleted it from her count. On the other hand, 

 those investigators who are prejudiced in favor 

 of stimulation of X rays are even more guilty, 

 for they sometimes contrive their experiments 

 in such a manner as to include basic contra- 

 dictions. 



Nevertheless, the great bulk of experiments 

 and observations of plants exposed to the action 

 of X rays constitutes a unique body of biological 

 data, interesting both in their theoretical and 

 their practical aspects. 



Investigations Performed in the 

 Electrobiological Laboratory 



We were guided by the above considerations 

 when we decided to answer, by a series of 

 systematic experiments on the effect of radiation 

 on various species of plants, including agricul- 

 turally significant ones, the question posed by 

 our predecessors concerning the existence of 

 stimulating X-ray doses. But we expanded the 

 question of stimulation to include the question of 

 yield, and thus we not only brought the plants up 

 to the fruit -bearing stage of their development 

 but analyzed the yield as well. 



The experiments were first conducted in a 

 laboratory for the biontization of seeds which in 

 1935 became part of the All -Union Institute for 

 Fertilizers, Soil Science, and Agricultural 

 Engineering, and later of the All -Union Institute 

 for Electrification of Agriculture. When the 

 activities of the latter were terminated, the 

 laboratory was transferred to the Timiryazev 

 Agricultural Academy. 



Our experiments began in 1931, and our first 

 subject was rye. This was a good choice for, 

 as we shall see later, rye proved to be very 

 sensitive to X rays. 



Rye . In order to discover the principles 

 governing the process, we systematically in- 

 creased the dosage for each succeeding experi- 

 ment in the following order: 250, 500, 750, 

 1000, 2000, 4000, and 8000 r. Not content with 

 varying the X rays quantitatively, we also tried 

 qualitative variations in our experiments, i. e. , 

 we used hard and soft rays. Seeds soaked for 12 

 hours as well as sprouted ones were irradiated. 

 We shall present the findings of these experi- 

 ments separately. 



Rye sprouts (investigations of Breslavets , 

 Afanas'eva, and Medvedeva) . For irradiation 

 we used for the most part freshly sprouted 

 seeds of rye, but since we did not select the 

 sprouts for irradiation with sufficient care, 

 some of them attained 1/2 centimeter in size. 

 We believe that this difference in size is largely 

 responsible for the highly uneven manner in 

 which the irradiated sprouts came up. Immedi- 

 ately after irradiation the sprouts were planted 

 in flower pots, several per pot. The plants 

 grew there for 27 days, after which they were 

 planted, one at a time, in a heavily fertilized 

 plot of ground. While the plants were still in 

 the pots, before transplanting, they were photo- 

 graphed. In this photograph, differences in 

 their development (depending on the dosages 

 they had received) were clearly apparent. 



Table 2 

 (based on the data of Breslavets, Medvedeva, and Afanas'eva, 1935) 



Editor's note: h.r. and s.r. refer to hard and soft X rays respectively. 



15 



