7 H 
Miller.—A Physiological Study of the 
Water Content .—The large amount of water which seeds and seedlings 
absorb during the process of germination is shown by the tables and curves. 
The per cent, of water in the hypocotyls and roots rises very rapidly, so that 
at Stage I, only three days after planting, it has almost reached the 
maximum. After that it rises but little and remains almost constant 
for all the other stages examined. The per cent, of water in the cotyledons 
rises more gradually and does not become constant until they are changed 
into foliage organs. When we consider the great need of water in parts 
Length of Time m days. 
Fig. io. Ash, per cent, on dry basis. 
of the plant where growth and cell-division are taking place, the results 
obtained are as one would expect. Since water not only has a tonic effect 
upon the activity of protoplasm but is also the most valuable asset which 
the growing cells have to enable them to stretch, it is to be expected that 
the per cent, of water would early become a constant in the hypocotyls and 
t-S 
10 
.s 
t 
— 
V 
-I 
-- 
-- 
-3 
/ *. a * y 6 j 0 ? /* •• '2 'a 
Lerujhh of Time in Days. 
Fig. ii. Ash, amount in grams per ioo seedlings. 
roots. In the cotyledons we would not expect the maximum amount of 
water to be present until the cells there begin to stretch and the cotyledons 
to function as foliage organs. 
Seeds planted in ordinary soil, and kept under the same conditions 
as those planted in sand, advance much faster than the latter during the 
early stages of germination. This is especially true in the length of time 
necessary for the hypocotyls to begin to show through the seed-coats a 
stage in the germination reached in twelve hours with seeds planted in 
rich loam and forty-eight hours with those in sand. This fact is probably 
