| Evaporation of Water from Plants. 307 
_ plants in light causes an increase in transpiration. This may 
 beexplained by the fact that the energy of the light rays 
_ absorbed by the chlorophyll, which energy is ordinarily partly 
_ wed in assimilation, is here wholly free to effect transpiration. | 
In the BOTANICAL GAZETTE for February, 1893, is an arti- 
_ de by Albert Schneider on the ‘‘Influence of anesthetics on 
_ planttranspiration.” In this article Mr. Schneider attempts 
to show how M. Jumelle came to erroneous conclusions. 
Quoting from Mr. Schneider’s article: ‘‘Jumelle has lately 
been carrying on a controversy with Verschaffelt who main- 
tains that ether increases transpiration in the dark as well as 
inthe light. This Jumelle has attempted to disprove in his 
inal paper on anesthetized plants.” 
Mr. Schneider has evidently been a little careless in his 
reading or else has failed to indicate where he received his 
information. The only controversy, so far as I know, be- 
‘ween M. Jumelle and MM. Verschaffelt has been on the re- 
cagagtely dioxide to transpiration in the light and in 
iit re mentioned in this paper. M. Jumelle’s fi- 
cle (I. ¢.) has nothing in particular to say inregardto an- 
4 asthetized plants but deals wholly with the problem under 
P it cee eween himself and MM. Verschaffelt. Further 
Sp aga Says: ‘‘By way of criticism it must be pointed 
3 "a in the first place, Jumelle as well as Verschaffelt 
aed ste dagagd of plants in their experiments and hence 
> Richt ay ey are of little practical value.” This criticism 
justly made had these investigators used, for the 
re of ey : ? ’ 
Mater absorbed by the as did Mr. Schneider, the amount of 
: red as the ; zi 
_— beanthes, properly measured it, the results obtained from 
~ he used enti. 
“ how ; i 
me ee ies Investigators used branches as well as 
— Terning ne 
n 
: Petiments, sig to Part 111 of Mr. Schneider's article, ‘‘Ex- 
is made a ve fanspiration of entire plants”; first of all he 
wate; a 4 §reat mistake in assuming that the amount 
ce ae ea a the roots of a plant represents the 
spied.” By consulting Dr. Oscar Eberdt’s inves- 
