INFLUENCE OF THE ALKALI SALTS UPON THE GROWTH OF RICE PLANTS. 25 I 
magnesium chloride 1/2000 Mol., calcium chloride i/roooo Mol., sodium 
sulphate i/ioo Mol., sodium chloride 1/100M0L, sodium carbonate 1/200- 
1/1000 Mol., and sodium bicarbonate 1/200 Mol. 
To verify the results obtained in the above experiment, we planned 
another series of experiments in the following manner. 
On June 13th (1912), 25 rice seeds of almost uniform size and specific 
gravity (1.158-1. 185) were sown in beakers, about 5.5 cm. in diameter and 
7 cm. deep, each containing 30 cc. of 1/2, 1/5, 1/10, 1/50, 1/100, 1/500, 
1/1000 and 1/5000 normal solutions of each salt, while distilled water 
served as control. These beakers were kept in a room of ordinary tempera- 
ture and covered with a glass plate until the seedlings attained a height of 
about 1 5 mm. The evaporated water was supplemented with distilled water 
from time to time to keep solutions always in their initial concentrations. 
After 36 days, the difference in their development was very striking 
when the measurements were made as shown in Table I p. 252. 
In this case as in the previous experiment, the growth of the seedlings 
was also injured or stimulated by each salt according to the concen- 
tration. In the concentration at which the toxic action ceased, the stimu- 
lating action began and attained its maximum point in certain dilution. 
The growth was injured by magnesium sulphate in concentration of greater 
than 1/100 normal and highly stimulated by 1/500 normal. Magnesium 
chloride was also toxic in concentration greater than 1/100 normal and 
attained its highest stimulating point in concentration of 1/5000 normal. 
The toxic concentration of calcium chloride, sodium sulphate, sodium 
chloride, sodium carbonate and bicarbonate was each in concentration greater 
than 1/100, 1/50, 1/100, 1/100, 1/50 normal respectively and their highest 
stimulation was reached in dilution of 1/1000, 1/100, 1/100, 1/500 and 
1/500 normal respectively. 
For the sake of convenience of comparison, the concentration of toxi- 
city and stimulation of the seven salts in the above two experiments are 
brought together in Table II p. 252. 
1) It is assumed that the plant is ill affected by the salts, if the length of root be half that 
of control plants, even though the length of leaf be greater than that of the control leaf. 
