172 
If we compare the data secured from these two experiments, we find 
that in the first, with 2.5 cm. of cortex removed, there is a difference of 
over eight hours in the wilting of the corticated and decorticated stem; 
and in the second, with only 1 cm. of cortex removed, there is’a difference 
of only about three hours. Now, if we take for granted that the two 
corticated stems, if under same conditions, would have wilted at about 
the same time, we have in the decorticated stems for a difference of 1.5 
cm. of cortex removed about five hours difference in their wilting. 
It is not supposed that this will not vary, nor that stems from other 
plants will give the same data, for different stems take up water at differ- 
ent rates; but the following, maple, oak, aster cordifolius, wild cherry, 
Indian mallow, rose, bittersweet, dahlia and chrysanthemum, with which 
two experiments were tried from all but the rose and dahlia, gave a sim- 
ilar relation between the length of cortex removed and the time of wilting. 
With some of the experiments wilting was slow on account of so much 
moisture being present in the atmosphere, while in others it was rapid, 
due to the absence of moisture. But in no instance was it evident that 
the decorticated stem wilted sooner than the corticated one, though with 
the tomato and gladiolus the time was apparently the same. 
Aster cordifolius gave the best results. In the first experiment with it 
the corticated wilted in about forty-five hours; the decorticated, with 1 
cm. of cortex removed, wilted in about sixty-four hours. In the duplicate, 
the corticated wilted in about fifty-six hours; the decorticated, with 2 em. 
of cortex removed, wilted in about ninety hours. It was cloudy all the 
time that these two experiments were being carried on, and part of the 
time was raining, so that transpiration was slow. 
If we compare these two experiments we find that in the first there is 
nineteen hours’ difference in the wilting of corticated stem, and decorti- 
cated with 1 cm. of cortex removed, and in the duplicate there is thirty- 
four hours’ difference in the wilting of corticated stem and decorticated 
with 2 em. of cortex removed. The data secured from the other experi- 
ments, except those mentioned as giving no results, were not so marked 
as the aster. The data from the rose were furnished by Dr. Arthur. Only 
one experiment was tried but the result was good, the decorticated being 
almost as fresh as at first, when the corticated had wilted. 
It must be remembered that the results given are only approximate, 
as the eye had to decide when the stems had wilted. With the use of 
suitable apparatus we might discover a relation between the time of wilt- 
