202 



EFFECTS ON PLANT RESPIRATION 



o 



Experiment 80. 

 Effect of radium rays on respiration 

 of germinating wheat grains. 



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ooi 



2. Effect on Anaerobic Respiration 



Experiment 8i 



Three seeds of the pea {Pisum sativum)^ soaked in tap-water over 

 night, were freed from their seed-coats and then found to weigh 1.41 

 gm. They were placed in a test-tube of mercury inverted over a 

 mercury bath. In the tube with the peas, and in contact with them, 

 was placed a celluloid rod coated with " Lieber's radium coating " of 

 10,000 activity. Thus the seeds came under the influence of the a 

 rays and the emanation, as well as of the /9 and y rays. 



The control test-tube contained three seeds, also weighing, without 

 their seed-coats, 1.41 gm. 



Observations were recorded as follows : 



Volume of Gas Evolved 

 Time of Observation 

 April 15, 5:00 P. M. 

 " 16, 10: 18 A. M. 

 " 17, 4: 30 P. M. 

 " 18, 9:20 A.M. 

 " 18, 6:40 P. M. 

 " i9i 9: 30 A. M. 



