EFFECTS ON PLANT RESPIRATION 205 



Results obtained by the crude device employed for testing the 

 effects of the rays on anaerobic respiration seem to indicate that an 

 exposure to a radium-coated rod (a, /9 and j rays, and the emanation) 

 caused a retardation of the process in germinating pea seeds, and 

 the same kind of result followed exposure to 5 mg. of radium bro- 

 mide of 1,500,000 X in the sealed glass tube. In one experiment, 

 however, a decided increase in the evolution of gas followed expo- 

 sure to radium of 10,000 x in a sealed tube, and also exposure to 

 radio-tellurium. 



A comparison of the results seems to indicate^that anaerobic and 

 normal aerobic respiration of germinating pea seeds are affected in 

 the opposite manner by radium rays, the former being retarded, the 

 latter accelerated, but the data are quite too meager to permit of a 

 more definite statement. The question needs further experimental 

 investicration. 



