1920] 



SNOW— DIA PHRA GMS 



3" 



the 



3f moisture, and was found, upon being tested with 

 to register 2 mm. too low. As the variation in 



en 20 mm., it was not thought necessarv to correct 



TABLE X 



Growth and structure of Scirpus validus: culm i grown under atmospheric 



pressure; culm 2 grown under 60-80 mm. pressure 



Culm no. 







1 

 2 



9S-I3S 

 95-135 



135-173 

 J 3S-i73 





Diameter 



in MM. 



1.85 

 1.79 



1.86 



i-95 





Walls in mm. 



Outer 





0.130 

 0.123 



O.I33 

 0-I35 



Inner 



O.058 



. 065 



O.082 



Spaces 



Large 



7 

 4 



12 



7 



Small 



17 

 15 



12 

 15 



Diaphragm 



distance 



IN MM. 



Growth 



(mm. per 



hour) 





2.50 

 2.36 



2.41 

 2.29 



0.62 

 0.52 



0.80 

 0.89 



TABLE XI 



Increase in diaphragm distance in mm. 



Region 



No. 1 over no. 2 



95 



59 

 135 

 173 



039 

 0.19 



0.12 



* Before the experiment. 



TABLE XII 



Diaphragm distance and rate of growth of Scirpus validus 



UNDER REDUCED ATMOSPHERIC PRESSURE 



Experiment no. 



I 



Culm no 



Average distance 



between diaphragms 



in mm. 



11 



in 



1 

 2 



2.96* 

 4.76 



3 96 



* 



1 .90* 



2.96 



318 



2.46* 

 2-33 



Average growth rate 

 in mm. per hour 





I.02* 



0.43 

 O.32 



O.84* 

 O.62 



O.44 



O.70* 

 O.68 



* Control culms grown under greenhouse conditions. 



for this error. On the average 5 liters of air passed through the 

 apparatus per hour. Culm 1 was the control and culm 2 the 

 experimental one. Tables X, XI, and XII give the results. 



