Aug. 15,1914 
Oxidases in Potatoes 
39i 
OXIDASE ACTIVITY OF THE JUICE OF THE SHOOTS 
The procedure was very much like that used with healthy potato 
plants. The first experiments were carried out on the whole shoot of 
the plants. The results are summarized in Table IX. 
There is no definite tendency observable in these results. The diluting 
influence of the stems is apparently more than compensated for by the 
Fig. 13.—Curve showing oxidation of pyrogallol in the presence of the juice of potato tubers. 
relatively higher oxidase content of the foliage of the older plants. Ail 
of the plants were started at the same time, so that from the viewpoint 
of age the results are comparable. As is shown by Table IX, no direct 
correlation can be found between the age or weight of the shoot and the 
oxidase content. These results are further discussed, together with other 
data on diseased foliage, on page 399. 
OXIDASE ACTIVITY OF THE JUICE OF THE LEAVES 
The results obtained in working with the foliage of curly-dwarf potato 
plants rather than with the whole shoots are given in Table X. 
