

Vol. VI June: 12, iQi<. no^ ii 



JOURNAL O 



RESEARCH 



CONTENTS 



Page 



Effect of Rontgen Says on the Tobacco, or Cigarette, Beetle 

 and the Results of Experiments with a New Form of 

 Rontgen Tube - - --- - _ - 383 



G. A. RUIWER 



Stimulating Influence of Arsenic upon the Nitrogen-Fixing 

 Organisms of the Soil - - - - - - - 389 



J. E. GREAVES 



Transmission and Control of Bacterial Wilt of Cucurbits - 417 

 FREDERICK V. RAND and ELLA M. A. ENLOWS 



DEPARTMENT OF AGRICULTURE 



WASHINGTON, D.C 



\k\ 



WAeHINOTON : GOVERNMENT PRINTING OFFICE : l«t» 



