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is completed the protoplasm is withdrawn to neighboring cells, 
where it may be of further service in the plant economy. The 
same hypothesis also explains the cause of the sudden disappear- 
ance of protoplasm in the autumn leaves of deciduous trees. The 
contents of the leaf cells, on the approach of cold or other dis- 
agreeable environment, suddenly wander back through the 
petioles into the stem, just as the plasmodium withdraws an arm 
when it comes in contact with anything disagreeable. 
This view, he says, is sustained by the fact that among the 
large numbers of fallen leaves already withered and sere, which 
he examined, no trace of protoplasm was found except in the guard 
cells of the stomatez. Here occurred both protoplasm and chloro- 
phyll grains. In all his previous examinations of healthy leaves, 
no trace of protoplasmic union between these cells and those sur- _ 
rounding them was found. Therefore it would be impossible for 
them to lose their contents by the means suggested. In answer 
to the question, how they obtained their supply in the first place ? 
he says they may have received protoplasm and chromatophores 
when first cut off from the neighboring epidermal cells, and that 
probably these contents were at first connected with those of the 
neighboring cells, and later the perforations were closed. Ac- 
cording to this notion they must have been obliged to furnish all 
their own organic nourishment after this separation occurred. 
The reason for this isolation he finds in the supposition that were 
they subject to the otherwise universal exchange of organic ma- 
terial they would, at times, be deprived of turgor=producing sub- 
stances, so fail in their office of opening and closing. 
In conclusion, he states that in germinating seeds no union 
exists between the protoplasm of the embryo and that of the 
neighboring cells, neither is it found between the haustoria of 
parasitical plants and the cells of their hosts. This facts offers no 
objection to his view, as according to it, only the organic materi- 
al, which is insoluble in water, is transferred by these protoplas- 
mic threads. Wortmann has shown that the change of starch to 
a material soluble in water is accomplished by diastase only in the 
holders of reserve material, such as starch-holding seeds, etc. 
Accordingly solutions occurs here which may feed the plant by 
osmotical processes. 
