480 
Philippine Journal of Science 
1920 
was within twenty-four hours. The tube with its contents was 
weighed, the plant material was removed (and preserved for 
the dry- weight determination) , and the tube was finally weighed 
dry. From the data thus obtained the green weight and the 
water content of the tops were determined, the latter being fi- 
nally expressed as percentage on the basis of green weights. 
RESULTS 
AERIAL CONDITIONS OF THE EXPERIMENT SERIES 
Before proceeding to the presentation of the results obtained 
from the plants it will be well to present, once for all, the data 
that characterize the aerial conditions for the various experiment 
Table 4 . — Maximum and minimum temperatures and average daily at- 
mometric and radio -atmometric indices for the different experiment 
periods. 
• The atmometric index is the daily rate of water loss from standard white spherical 
porous-cup atmometer. The radio-atmometric index is the daily excess of water loss from 
standard black spherical atmometer, above that from the white. 
