338 BOTANICAL GAZETTE [aay 
No. 3—required 0.8°° of standard acid. 
No. 4—required 10.3°¢ of standard acid. 
No. 5—required 7 .6°° of standard acid.'9 
After six days in the incubator the quantitative estimations were 
repeated. 
No. 1—required 0.6°° standard acid=gain of 0.0°°. 
No. 2—required 1.9°° standard acid =gain of 1.3°°. 
0. 3—Tequired 1.3°° standard acid=gain of 0.5°°. 
No. 4—required 10.9°° standard acid = gain of 0.6°°. 
0. 5—required g.2°° standard acid =gain of 1.6°°. 
The results in the case of the phaseolin, the proto-proteose, and 
the deutero-albumose B are well defined; those with the hetero- 
albumose and the deutero-albumose A were not sufficiently marked 
to lead to a definite conclusion. 
A second experiment was tried with the four proteose preparations 
after the ammonium sulphate had been removed from the two deu- 
tero-proteoses. In these trials, instead of using the ereptase prepara- 
tion used in the previous experiment, an extract was made from some 
bean meal and filtered several times through pulp filters until it was 
nearly clear. Of each of the four proteoses 0.125%" was dissolved 
in 25°° of water. Ten cubic centimeters of the bean extract were 
placed in each of eight test tubes and four of the portions boiled. 
Ten cubic centimeters of each proteose solution were added to a boiled, 
and 10° to an unboiled, portion of the extract. Nine drops of toluol 
were added to each tube, the tubes corked, shaken, and kept in the 
incubator for sixty-five hours. At the expiration of that time the 
contents of all the test tubes were boiled and filtered. Of each 
filtrate 10° were removed to a clean test tube, 5°° of a ro per cent. 
sodium hydroxide solution added, and then dilute copper sulphate 
to the maximum biuret reaction. After standing for several minutes 
the strengths of the biuret reactions from the boiled and unboiled 
digestions of the different proteoses were compared. The reactions 
showed that all of the proteoses were attacked by the enzyme. boas 
portions of the filtrates not used in the comparative biuret reactions 
were employed to test for tryptophan. The unboiled digestions 
with proto-proteose, hetero-proteose, and deutero-proteose A gave 
9 The ammonium sulphate in the last two proteose preparations accounts for the 
high nitrogen in the filtrates from the tannic acid precipitates. 
Z 
Z 
Ne ee os ee RE en ee Pe ES SY a eT ee er he eee 
