108 BOTANICAL GAZETTE. 
the venation appearing as a pale network in the dark ground, 
Paler colors result if but little starch is present at the time of the 
experiment, , 
It will readily be seen how useful the above method is for the 
purpose of demonstrating the absence of starch from etiolated 
leaves, the white portions of variegated foliage, ete , and the 
sequel shows that the method affords means of obtaining far more 
ly 
reb 
in the evening may be quite empty of starch the next morning. 
This depends upon the temperature and health of the plant, but 
occurs normally during the summer in plants growing in the 
open. large number of experiments are given in support oe 
this, showing how the rapidity and completion of the process de- 
efore sunrise shows no trace of starch ; dhe 
plant during the day is found to be mare 
and more filled with starch towards the afternoon. ie 
: ome curious results were arrived at as to the effect of grow- 
ing parts on the rapidity of the emptying of the leaves; some 
re investigation. 
Differences in the wei ; feaven 
the color produced by th 
: € iodine test, as well as some other ob- 
Servations, lead to a bette 
ght of the leaves and in the intensity of 
runderstanding of a fact already knowD — 
Pes PF bn a eens Oe 
