724 Miller.—A Physiological Study of the 
composition there would from the standpoint of energy be most advanta¬ 
geous to the plant. This, however, cannot be taken as a criterion for the 
processes which take place in life, since often they seem to represent, as 
far as we can see, a useless waste of energy. To be certain, however, that 
oil-migration does take place, the oil which is found in the growing parts 
must be shown to be of the same composition as that of the reserve from 
which it is supposed to have come, and the possibility of oil-migration 
through plant-membranes must be more firmly established than it is at 
present. If the oil is not changed in its transportation, it is the only 
insoluble reserve, so far as is known, which is not. The fact that the 
amount of free acid in the oil does not reach a high amount at the earlier 
stages of germination does not necessarily indicate that the oil is being 
transported as neutral oil from its place of reserve. The oil may be broken 
down in the cotyledons and the products transported as soon as they are 
formed, so that no accumulation of them takes place. In fact, in the later 
stages, the amount of acid rises to § of the oily content of the cotyledons, 
and to over \ of that of the hypocotyls and roots. This appears, too, at 
a time when the greatest changes are taking place in the seedling, and 
indicates that an accumulation of acid takes place because of the inability to 
transport it as rapidly as it is formed. 
Summary. 
During the first three days after the planting of the seeds, the rudi¬ 
mentary roots and hypocotyls reach a length of 2-5 to 3-5 cm. 
The cotyledons have absorbed a quantity of water in that time equal 
to 50 % of their weight, while the per cent, of water in the hypocotyls and 
roots amounts to 90 % of their weight. During this time the most intensive 
respiration in the development of the seedling apparently takes place, for 
at the end of this period the total weight of the seedling amounts to only 
i that of the resting seed. Five-sixths of the sugar content of the coty¬ 
ledons, f of the oil, and almost £ of the protein has disappeared. The 
rudimentary hypocotyls and roots at first increase in length by the stretch¬ 
ing of the tip, but later in this period the cells of the growing point of 
the root become active and the increase in length is brought about in the 
usual way. 
As the development of the seedling advances, the depletion of the 
reserves in the cotyledons advances from the point nearest the hypocotyls 
to the end remote from it. The most marked change in the reserve 
products takes place between the time when the cotyledons are breaking 
through the ground and the period when they are fully developed into 
foliage organs. This occurred between the fifth and tenth days under the 
conditions of this experiment. 
