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in what way the removal of the cortex at the cut end of a shoot would 
delay wilting. In the unprepared shoot used the wood-cells in touch with 
the water were only those exposed by the cross-section of the stem, but in 
the decorticated one, besides these, the cells from which the cortex had 
been removed, were also brought in touch with the water, thereby in- 
creasing the number of wood-cells in contact with the water in the de- 
corticated shoot. As it has already been shown that the cortex is a poor 
conductor of water, we can see that it will prevent the water from reach- 
ing the wood-cells beneath, but if removed from the shoot the water is 
brought in contact with these cells the same as with those exposed at the 
cut end of the shoot, and as results show, is taken up by them. 
The turgescence of a shoot depends upon the amount of water supplied 
to it in relation to the amount given off by transpiration, and this can be 
prolonged by providing a greater supply of water, or by decreasing the 
rate of transpiration. As the latter, however, is dependent upon the con- 
dition of the atmosphere, it is beyond our control; but the supply of water 
is not. Pressure can be used to increase this supply to the cut shoot, and 
by this guttation can be produced in the vigorous shoot, and turgescence 
can be restored in the wilted. But this is too inconvenient to be of much 
practical value in preserving cut shoots in fresh condition. If the supply 
of water to a cut shoot can be increased by removing the cortex from 
above the cut end, this will give a very simple method for prolonging 
turgescence, a method that all may employ who are lovers of cut flowers 
and delight to preserve them as long as possible. 
In the experiment mentioned, as the decorticated did not wilt as soon 
as the corticated shoot, the former must have received more water than 
the latter. If the end of a cut shoot that is in water be removed at differ- 
ent intervals so that fresh cells are exposed to the water, the shoot will 
not wilt as soon as it would if the fresh cells were not exposed. This is 
due to the fact that as the cells take up the water they act as a filter and 
stop all foreign matter present in the water, and so in time the cells are 
choked, and can not take up more water. When the cortex is removed 
more wood-cells are exposed, and it may be that the water is not taken up 
any faster by the shoot, but on account of the greater surface of cells 
exposed they do not choke so soon. But if the cells exposed by the cross- 
section do not overload the carrying capacity of the shoot, it should take 
up more water when the cortex is removed. 
