AGRICUI.TURAI, BOTAXY, CHEMISTRY AND PHYSIOLOGY OF PI^ANTS I427 



Table III. — Total nitrogen in various parts of .soybeans and fixation 

 at different periods [gms. per jar of ^ plants). 



Age 

 of plant 



Nitrogen 

 in tops 



Nitrogen 

 in roots 



Nitrogen 

 in nodules 



Nitrogen 



in whole 



plant 



Nitrogen 

 in seeds 



Nitrogen 

 fixed 



The green of the old leaves disappeared from the margins first, then the 

 whole leaves became yellow and dropped from the plant. The process 

 repeated itself until there was not nitrogen enough left to give colour to 

 another leaf, when a- pale green or even a yellow leaf was formed. The 

 whole appearance of the plants was very characteristic. 



II. Relative percentages of nitrogenous compounds in the various 

 parts of the soybean and coivpea at definite periods of growth. — Determi- 

 nations of total, soluble and insoluble nitrogen were made on the dry 

 matter of plants grown under specially controlled conditions. . Total 



