FORM'ATION OF PROTEIDS ETC. 495 



nitrates assimilated apparently served in this case only for t!ie 

 production of amido-compounds. 



IV. EXPERIMENT WITH YOUNG BARLEY 

 PLANTS. 



On March 6, some young barley plants were taken from the 

 field, and put in a 0.2% solution of soduim nitrate, in diffuse day 

 light for 7 days at temperature of Min. 5°C and Max. I5°C. Thus 

 the plants had sufficient time to store up some nitrate. On the 

 13th the plants were removed from the solution, washed well, and 

 one portion of the plant was directly dried for analysis, while the 

 other portion was divided into 2 parts. One of these was ex2:>osed 

 to day light, and the other kept in the dark, both being put in a 

 ^% glucose solution half saturated with gypsum and once in every 

 4 days, they were transferred in solutions containing 0.1% KH2PO4 

 0.1% MgS04, half saturated with gypsum. During the experiment 

 the temperature was Min. 8°C. and Max. I5°C. After 7 days, the 

 plants were removed from the solutions, washed well, and dried for 

 analysis. 



IN 100 TARTS OF DRY MATTER. 





Control jjlants 

 dried on 

 13th 



Plants in day 

 light dried 

 on 20th 



Plants in dark 

 dried on 

 20th 



Total nitrogen 



5.1S 



5-34 



6.19 



All)uminoid nitrogen 



2.26 



1.71 



1.49 





0.25 



0.17 



O-30 





14-13 



10.69 



9-3' 



