82 TRANSACTIONS OF THE 
and the experiment above noted seems to bear out that 
idea also. 
4. DISCUSSION AND CONCLUSION. 
It is believed that the evidence furnished is suf- 
ficient to support the conclusion that pure distilled water 
per se is not toxic or injurious to plants, and that various 
other factors enter in to cause the deterioration noted 
when plants are placed in that medium. 
Of course by qualifying the assertion to include pure 
distilled water only, we have thus eliminated the effect 
that may be produced by toxic substances in the dis- 
tilled water, no matter from whence derived. The 
abundance of work that has been done on the toxicity of 
various substances to plant tissues would of course lead 
us to expect injurious effects if such substances were 
present in any quantity in the distilled water. With that 
phase of the question we are therefore not much con- 
cerned at present. With a distilled water prepared as 
indicated, and with a specific conductivity. which is 
approximately 2x10-°, we have a water sufficiently pure 
for use in the consideration of other aspects of the ques- 
tion, and attention is directed to these. 
The evidence presented has inclined us strongly to 
the view that the fundamental basis of the deterioration 
of plants in distilled water rests upon the food relation of 
such plants, but that, on the other hand, an exosmosis of 
food materials or nutrient salts is in no way responsi- 
ble for the difficulty. It is considered that the question 
of the food relation plays an important role in the incip- 
iency of the disorder, but that this is quickly followed 
by factors which have been initiated as a result of the 
inimical food or nutrient relation. 
A plant must assuredly have food in order to thrive. 
The more food it has stored up in its tissues, the longer 
it can survive in a medium devoid of it. But because 
of the absence of available food it is believed that the 
tissues of the plant begin to become disorganized and 
in that condition fall a ready prey to bacterial and fung- 
ous action, which may then set in and play a very impor- 
tant part in the subsequent decomposition of the tissues. 
