the Respiratory Exchanges of Leaves. 71 1 
floated on water. They were then placed between a folded sheet of moistened 
paper, and so inserted into the leaf-chamber. 
The first experiment is chosen as an example of the effect of a small 
dose of chloroform, insufficient to produce disorganization. 
Fig. 13. 
Experiment XII. September 24, i 9 ° 9 ‘ Dose, o*i c.c. for ten minutes, 
repeated after three hours. Temperature, 16-17° C. 
In this experiment the effect of the first dose of chloroform was 
a marked though relatively brief stimulation of both C 0 2 output and 0 2 
intake, more especially of the latter (Fig. 13). The second dose produced 
a similar though rather smaller effect. 
It is interesting to notice that the changes in the respiratory coefficient 
following the two doses are concordant, rising gradually from 0.7 — after 
the first dose in three hours to o-8, after the second reaching eventually 
0-9. The same change was shown by other experiments. 
The next two experiments are examples of cases in which the dose of 
chloroform was sufficient to produce disorganization. 
Experiment XIII. October 15, 1909. Dose, 0*3 c.c., administered in 
six doses of 0-05 c.c. each at intervals of two and a half minutes ; duration of 
exposure, fifteen minutes. Temperature, 15.7-17 0 C. 
After chloroform the leaves were curled and rather flaccid, and their 
rate of respiration had greatly diminished ; it fell still further to a very low 
level within six hours. In this case, however, unlike Helianthus and Cherry 
3 c 2 
