upon Respiration and Assimilation. 
1083 
and included in the cut-off shoots. Those shoots which were cut off 
immediately above their seed gave a much higher value for their respira¬ 
tion than those cut off half an inch above the seed. Presumably the 
actively growing stem respires more energetically than the nearly mature 
leaf-blades. 
For the above reason the curves cannot be compared directly by 
superposing them all with the same base line, but in Fig. 7 they are super¬ 
posed all starting from the same point— 
that of the normal respiration just when Chloroform 
the dose of chloroform is given. 
It is at once seen that the effects of 
the different doses fall into a progressive 
series from B to E, which we can easily 
compare by means of this schema. 
The falling interrupted line in the 
schema represents the curve of C 0 2 -pro- normal 
duction in a normal leaf cut off and kept in RES . R 
the dark. This serves as a standard of the 
respiration uninfluenced by chloroform. 
The smallest dose given in this sec¬ 
tion, o*i c.c., causes the C 0 2 -production to 
rise at once with an outburst which gra¬ 
dually dies away, but yet leaves the C 0 2 
as great as in the normal leaf, even after 
twelve hours, type B. 
Type C is given by a dose of 0-3 c.c.; 
here there is a similar initial outburst, but 
this falls off more quickly, so that it gets 
below the normal leaf after six hours ; then 
recovery sets in and the value of the normal 
leaf is attained. 
One c.c. of chloroform produces type 
D, in which the falling off from the initial 
outburst is still earlier and steeper, and is Fig. 7. 
followed by no sign of recovery; instead, 
the C 0 2 -production slowly diminishes hour after hour. With a much 
stronger dose, 10 c.c., we get type E, in which there is no detectable 
initial outburst, but the C 0 2 falls off rapidly from the beginning and the 
curve sweeps quickly down to zero. No doubt there is a brief outburst 
of C 0 2 here also, but this augmentation is more than masked by the great 
diminution of the C 0 2 during the remainder of the one- or two-hour reading 
taken immediately after chloroforming. 
Of these doses of chloroform all except the weakest caused the leaf 
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