So Frederic Czapek. — The Anti-ferment Reaction in 
Weight of alcoholic extract .... 
Thereof soluble in water 
Titration with AgN 0 3 ...... 
Residue after extraction with alcohol 
The part soluble in water titrated with 
I. 
0-0189 g. 
0-0148 g. 
0.75 cc. 
2*0327 g. 
II. 
0-0188 g. 
0-0146 g. 
0.75 cc. 
2-0725 g. 
Control. 
0-0154 g. 
0- 0102 g. 
no reduction. 
1- 4802 g. 
>S N0 3 
0-50 cc. 
no reduction. 
Insoluble in water ....... 
Insoluble in alcohol and soluble in water 
2-0031 g. 
0-0296 g. 
2-0442 g. 
0-0283 g. 
1-4564 g- 
0-238 g. 
In this experiment only 2-25 cc. of silver solution were consumed for 
the substances soluble in water and alcohol. By far the larger quantity of 
the reducing substances was soluble in absolute alcohol, as shown by the 
high titration value of the alcohol extract, a smaller quantity of them was 
insoluble in alcohol and only soluble in water. This last portion, reducing 
Fehling’s solution and giving the well-known test with phenyl-hydrazine, 
must contain principally sugar. The fitness of the Baumann method for 
investigating the processes of metabolism in geotropically stimulated roots 
was still to be tested by investigating the increased values obtained by 
silver titration in the case of alcoholic and watery extracts of geotropically 
stimulated roots in comparison with unstimulated specimens. 
Two sets of unstimulated roots and two sets of roots stimulated by 
thirty minutes in a horizontal position were used for analysis. A control 
experiment was included, and the arrangement was otherwise as in the 
above described instance : — 
Not stimulated. 
I. The glasses .... 1-0468 g. 1-4197 g. 
II. Glasses with root-tips . 1-0678 g. 1-4461 g. 
III. The tips alone . . . 0-02 tog. 0-0264 g. 
IV. Alcoholic extract soluble 
in water ..... 0-0082 g. 0-0093 g. 
V. Alcoholic residue soluble 
in water ..... 0*0182 g. 0-0214 g. 
Titration of IV. .... 0-7500. 0-7500. 
Titration of V ..... 0-50 cc. 0-50 cc. 
Stimulated. Control. 
1-3377 g- 1-0858 g. 1-3925 g* 
1-3503 g. I- 1 1 13 g- 1-3925 g- 
0-02 26 g. 0-0255 g. 
0-0087 g. o-oio8g. 0-0053 g. 
0- 0172 g. 0-0190 g. 0-0131 g. 
1- oocc. i-oocc. — AgNO s 
0-50 cc. 0-50 cc. ,, 
The same test was carried out by rubbing up the fresh root-tips 
directly with glass-powder and absolute alcohol ; the subsequent pro- 
ceedings were the same. 
Not stimulated. Stimulated. Control. 
I. Alcoholic extract soluble 
in water 0*0081 g. 0*0084 g. 0-0093 g. 0-0087 g. 0-0048 g. 
II. Alcoholic residue soluble 
in water ..... 0-02 ng. 0-221 g. 0-0223 g. 0-240 g. 0-0170 g. 
