496 SOILS:' PROPERTIES AND MANAGEMENT 



experiments by various investigators, and their avail- 

 ability for the nutriment of higher plants : — 



Readily Assimilated 



Ammonium salts 

 Acetamide CH 3 . CO . NH 2 



Urea CO<wtt 2 



Barbituric acid (with calcium carbonate) 



CO \NH . CO/ CH5 



Alloxan CO<^ ' <g>CO 



Humates 



Assimilated 



Formamide H . CO . NH 2 



Glycine NH 2 . CH 2 . COOH 



Aminopropionic acid CH 3 . CH(XH 2 ) . COOH 



/NH, 

 Guanidine hydrochloride [C = NH HC1 



\NH 2 . 



Cyanuric acid CO<^t T tj ' p~/NH 



CO . NH 2 

 Oxamide 



CO . NH 2 



CH(NH 2 )COOH 

 Sodium aspartate 



CH 2 . COOH 



Peptone 



