[Vol. 2 



492 



ANNALS OF THE MISSOURI BOTANICAL GARDEN 



water. With that phase of the question we are therefore not 

 much concerned at present. With a distilled water prepared 

 as indicated, and with a specific conductivity which is approxi- 



mately 2X10 



6 



J 



have a water sufficiently pure for 



e consideration of other aspects of the question, and i 



m is directed to these. 



The evidence presented has inclined us strongly to the 



30 



to 



X) 



3 



25 



a) 



20 



o 



•H 



o 



m 

 P 



15 



10 



2 



4 



6 



8 



10 

 Days 



12 



14 



16 



18 



20 



Fig. 4. The conductivity curves for cultures in distilled water 20 

 days — after growth in full nutrient solution for 20 days. The initial 

 temperatures of the distilled water into which the roots were placed 

 were as follows : Nos. 21-24, 6.5° C; Nos. 25-28, 17.2°C; Nos. 29-32, 

 35 °C. 



that the fundamental basis of the deterioration of plants in 

 distilled water rests upon the food relations of such plants, 

 but that, on the other hand, an exosmosis of food materials or 

 nutrient salts is in no way responsible for the difficulty. It 

 is considered that the question of the food relation plays an 

 important role in the incipiency 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. 



