92 



BOTANICAL GAZETTE 



[august 



any more definite relations can be established. From the data 

 at hand the following facts seem established : 



1. Plant juices are good conductors, and the conductivity is 

 due in large measure to the dissolved mineral substances, while 

 the organic compounds play a minor part. 



2. The specific conductivity of the juice obtained from the 

 roots of plants is always considerably less than that of the juice 

 obtained from subaerial parts. 



3. The specific conductivity generally increases progressively 

 from the root upward, although in some cases the sap from the 

 stem has a higher conductivity than that from the leaves. 



4. In the majority of cases the specific conductivity is a 

 rough measure of the relative amounts of ash present in different 

 parts of the plant. 



Paksons Collegk, 



Fairfield, Iowa. 



f 



