192 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 5 



males were later placed with unexposed females; in another series 

 exposed females were placed with unexposed males; and in the third 

 both sexes were exposed to the rays. The exposure varied from 4 to 

 16 minutes in the different experiments. 



In a few of the cases no eggs were deposited but such occurrences 

 were explainable by factors which had nothing whatever to do with 

 the Roentgen rays. 



In the case of the exposed males placed with unexposed females, 

 even when the exposure ran as high as 16 minutes, eggs were deposited 

 in normal numbers and were found to be viable. In fact, the larvae 

 were bred to maturity. Exactly the same is true of all of the experi- 

 ments in the series in which the exposed females were placed with 

 unexposed males. In the third series, however, in which both sexes 

 were subjected to the rays for the varying periods no fertile eggs were 

 deposited. In this case the control failed to produce eggs so that 

 no conclusions can be drawn. 



The foregoing gives but a meager outline of the numerous experi- 

 ments that were performed. The results are possibly open to crit- 

 icism on account of the methods of manipulation that were followed. 

 There is so much difference in the effects of the rays upon human 

 beings depending upon the penetration, the length of the exposure, 

 the amperage and voltage, that it is conceivable that under some 

 conditions insects may be affected. Nevertheless, in all of the work 

 we have done it is not apparent that the rays have had any effect 

 whatever upon the fertility or the development of the various stages of 

 the several species utilized in the experiments. At any rate the rather 

 considerable amount of work done has not shown that there are any 

 indications of any practical utilization of X-rays in the destruction of 

 injurious species. 



President F. L. Washburn: Any question to ask Mr. Hunter? 



T. J. Headlee: Mr. President, have they gone far enough to 

 determine whether the rays of light in any way affect the transmission 

 of characters? 



W. D. Hunter: In no way at all. 



E, W. Berger: Mr. Chairman, I have recently conversed with 

 a man in Florida who is interested in the big business affairs of that 

 State, and he told. me that they were planning to sterilize the eggs 

 of the tobacco beetle in Cuba by means of the X-rays. He told me 

 that he was interested in the subject and was working on it at that 

 time. He seemed to have no doubt at all that the thing would be 

 successful. It was altogether new to me, and, of course, Doctor 

 Hunter's results here are all contradictory to this man's results. 



