1099 
upon Respiration and Assimilation . 
the continuous chloroforming of Section II, it will be found that a continuous 
concentration of n c.c. of chloroform per litre of air-current produces the 
same type of effect as an initial dose of 2 n or 3 n c.c. 
6. The other effects of chloroform upon Barley leaves are (1) destruc¬ 
tion of chlorophyll and (2) exudation of water through the stomata. In 
Cherry Laurel leaves we find in addition (3) browning of the leaf and (4) de¬ 
composition of the cyanogenetic glucoside. 
Effect of chloroform upon assimilation in leaves. 
7. Very minute doses of chloroform, which have no detectable effect 
in the dark, arrest assimilation in a lighted leaf and cause C 0 2 to be given 
out in the light. 
8. If the chloroform is given for a short period and at a very low 
concentration, then upon its removal the leaf may partially recover its 
assimilative power. 
9. Quite moderate doses of chloroform completely abolish the assimi¬ 
lative power. 
10. Larger doses of chloroform abolish all traces of assimilation so 
quickly that a leaf in the light reacts exactly the same as a leaf in the dark 
and shows the characteristic initial outburst of C 0 2 and the other stages 
described under the heading of respiration. 
In conclusion, I should like to express my thanks to Dr. F. F. Black¬ 
man for the use of his special apparatus and for his help in correlating 
these experimental results. 
