148 ISABURO NAGAT: 
By transferring the seedlings from the water to the moist-air chamber, 
the rate of development of the root becomes vigorous, while that of the shoot 
is very gradual, Twenty hulled grains (“Araki”) are allowed to germinate 
in distilled water at 27°C. At the end of 48 hours the average length 
of shoots was 10.55 mm; one of the grains was found to have a rootlet of 
2mm in length, the rest had none. After the measurement was made, the 
seedlings were placed on a moist filter paper and allowed to grow another 
24 hours at 27°C. Every one of them developed the root, and the average 
length reached was 11.65 mm. (Table X). 
TABLE X. Oryza sativa. 
Influence of oxygen on the development of radicle. 
Growth in length mm, 
first 48 hrs. in water next 24 hrs. in air 
Root 0.1 1.55 
Shoot 10.55 2.60 
The result is more pronounced in the case where the grains are brought 
to normal air from the oxygen free air in which they have been allowed to 
germinate (Table XT). 
TABLE XI. Oryza sativa, same as Table X. 
Growth in length mm. 
First 48 hrs. in oxygen NS 
free air 5 : - 
oxy. free air normal air 
in water 0 0 0 
Root! b 
on moist filter paper 0 0 10.3 
a in water less than 1 12.8 | 6.5 
Shoot ; 
won moist filter paper - 7.3 14.3 
As we see from the above figures, the development of the radicle vigor- 
ously commences as soon as oxygen becomes available. No growth of 
