564 
BOTANY: A. R. HAAS 
dish after the distilled water had been added, and care was taken not 
to let the cover touch the water at any time. The two quartz dishes 
each contained 650 cc, and two smaller quartz dishes each contained 
50 cc. of pure distilled water. One of the large quartz dishes had 65 
corn seedlings growing in it while the other had 77 seedlings. The 
seeds never came in contact with the water. The seedlings were grown 
in the culture for 7 days. The water in the dishes was made up daily 
to the same volume as at the start and the evaporation was kept 
approximately the same in each dish by covering or uncovering the extra 
holes in the covers. At the end of 7 days the corn roots were about 6 
inches long and apparently free from brown spots. The water was then 
tested as in the other experiments, the CO2 being expelled from the 
samples by running hydrogen (free from impurities) through them for 
45 minutes each. 
TABLE 3 
Results after CO2 was expelled 
Quartz dishes containing seedlings Quartz dishes containing only water 
65 seedlings : Water Ph+ 8 . 04 No seedlings : Water Ph+ 7 . 88 
77 seedlings : Water Ph+ 7 . 88 No seedlings : Water Ph+ 7 . 88 
The two covers bearing the seedlings were then lifted from the top 
of the quartz dishes and by means of a sharp razor blade (that had been 
thoroughly cleansed) the roots were cut off a short distance below the 
seed and were allowed to fall into the dishes in which they had been 
growing. The tops and the attached seeds were discarded. The paraf- 
fin covers were put on the dishes and the holes in the covers were closed 
by laying several layers of filter paper over them. After two weeks, 
numerous brown spots appeared on the roots, and many of the roots 
became soft and gelatinous toward the tip. After 4 weeks from the 
time that the experiment was first begun, the water in which the roots 
were decomposing appeared brownish, but possessed no disagreeable 
odor. Analysis of the water was made as described before. 
TABLE 4 
Results after CO2 was expelled 
Quartz dishes without roots: control Quartz dishes containing cut-off roots 
Control quartz dish Water Ph"^ 7 . 88 Quartz dish with decay- 
Control quartz dish Water Ph+ 7 . 88 ing roots Water Ph+ 8 . 04 
Quartz dish with decay- 
ing roots Water Ph+ 8.04 
Two new samples of water were 
taken to verify the results: 
Quartz dish with decay- 
ing roots Water Ph + 8 . 04 
Quartz dish with decay- 
ing roots Water Ph -|- 8 . 04 
