1902] THE STARCH OF EVERGREEN LEAVES 339 
Itis to be noticed that in Thea japonica the leaves from the 
first two plants showed no distinct opening of stomata, while : 
those from the third plant had open stomata. It seems, there- See 
tore, that there are some variations in the behavior of stomata of . 
‘thesame species, probably due more or less to the location of 
the plants. / | 
: Itis evident that many of the evergreen leaves examined 
_ lave stomata more or less open in day time during the 
SUMMARY. 
Jt The starch contents of evergreen leaves differ much at a 
sven time according to the different species. Monocotyledons 
erally contain less starch than dicotyledons, gymnosperms, 
_ M4 pteridophytes, or even none in some species. = 
_ > The starch in evergreen leaves, generally speaking, begins — 
bd “tease in November, reaching its minimum during January 
: the beginning of February, and increases again from the end 
. Many evergreen leaves in Tokyo and other parts of middle _ 
: ern Japan contain more or less starch in the mesophyll, — 
While ‘'S entirely absent in some species in the coldest time of © 
= starch found in evergreen leaves in winter is generally 
‘ Compared with that observed at other times of | 
‘tor : 
Th 
: ee a few species the starch is quite abundant. 
$ : es Starch is formed by photosynthesis in winter, though 
ra cog its translocation occurs in the same season. 
__'« Starch in the guard-cells becomes less or even entirel, 
_. ‘1 Many species, while a few species contain a moder: 
unt throughout the winter. ae SS 
: « majority of evergreen leaves in the northern part of 
ied lose the starch from the mesophyll and guard-cells 
While a little starch is still found in some species. os 
Starch content of evergreen leaves is generally more 
Spring than in late summer or early autumn. oe 
