ON THE RESERVE PROTEIN IN PLANTS. 
8l 
By exposure to boiling 5% NaCl solution the proteosomes 
were coagulated. This was observed with the petals of Punica 
and of Astilbe and the root of Thesium. 
Millon’s and biuret reactions are best made on objects free 
from tannin, as for instance, the root of Thesium. Both reac¬ 
tions were obtained after fixation of the proteosomes by dilute 
ammonia after the modification, described by Loew and Bokovny 
(Bot. C. 1889) ; biuret reaction was also obtained by boiling 
with a concentrated solution of copper sulphate solution, washing 
and moistening with concentrated solution of caustic potash. 
A small branch of Quercus dentata, showing in the young 
leaves as well as in the bark, during development in the spring, 
a large quantity of active albumen, was left for twelve days with 
the stem immersed in water. At the same time two of the 
leaves were placed in a small vessel with water. In the latter 
case, the respiration was of course restricted to a certain extent 
for obvious reasons. Both objects were placed in a corner of a 
room with only a moderate amount of lightfor twelve days, 
and then for two days in the dark. Now the leaves on the 
branch commenced to show brown spots, whereupon a micros¬ 
copical examination was made and it was found that there was 
no longer any starch in either case, but while the leaves on 
the branch no longer showed the reaction of active albumen, 
those kept in water still gave a moderate reaction. It might be 
objected here that there was just as much albumen still present 
in the former leaves, but it was only changed to passive albumen. 
But it has been shown by E. Schulze that protein compounds 
are transformed in plants kept in darkness into amido-acids, and 
that finally asparagin remains as a chief product. 
The gradual disappearance of the active albumen from the 
leaves stands in close relation to the formation of asparagin ; 
I found that while the fresh leaves of Quercus glandulifeva con¬ 
tained 0.218% of nitrogen in the form of asparagin (determined 
after Sachse- Kormann ), those kept for seven days in darkness 
contained 0.606%; therefore the asparagin was increased near¬ 
ly three times the original amount. 
A similar experiment was made with the leaves of Pœonia 
1) At the lower end of the branch a fresh surface was cut repeatedly in order to 
secure the sufficient ascent of water. 
