SOME STUDIES ON THE GERMINATION OF THE SEED OF ORYZA SATIVA. 115 
Similar data with the grains of Zea Mays (White Dent) show likewise 
the presence of a “semi-permeable ” septum. The measurement at the end 
of 72 hours in 24—29°C is as follows: 
aw Na Cl aM Na Cl Dist. water. 
20.78 % 26.49% 47.29% 
The vitality of the 
grains is not concerned 
with the selective 
permeability in Oryza 
as in other grain. The 
hulled grains (“ Kuma- 
moto ’’) are boiled for a 
few minutes with water 
to kill the embryo, 
and the semipermea- 
bility of the grain is 
tested. After 48 hours 
in the thermostat at 
28° C, the increase in 
weight in 1N NaCl 
and in distilled water 
is as follows :— 
1N NaCl 14.20% 
Dist. water 30.43% 
The seed covering 
of Oryza is found to be 
0 24 48 72 96 
Text-Fig. 1. Oryza sativa. Absorption of water by the grain. 
1 : 
(cf. Table I). « water, D-NNu Cl, cy NaCl. Ordinates, increase 
in wt.%; abscissa, no. of hours steeping. 
impermeable to sodium chloride, copper sulphate, mono-potassium phosphate, 
sulphuric acid, licium chloride, potassium bichromate, cane sugar, oxalic acid, 
and ammonium oxalate from the aqueous solution, but permeable to mercuric 
ehloride. A normal solution of mercuric chloride is absorbed just as easily 
as distilled water (See Table II). 
