H. B. Hutchinson and N. H. J. Miller 101 



the others. Tlie number of pods produced by the j)kints was — (1) 4, 

 (2) 5, (7) 3, (10) 2, and (11) 2. 



Additions of dextrose had no appreciable efl'ect, probably owing to 

 the presence in the seedlings of sufficient available non-nitrogenous 

 material for the production of asparagine from the small amount of 

 ammonium salt employed. 



The results of the three series of experiments show that ammonium 

 sulphate is directly assimilated by wheat and peas and that, in the case 

 of peas, there was no difference between the plants supplied with 

 annnonium salt and those which had sodium nitrate. The wheat 

 plants, however, showed a decided preference for nitrogen in the form 

 of nitrate. 



PerceiitiKje of nitrugen in plants manared respectiveli/ luith 

 Aiumoniuin Salts and Nitrates. 



Reference to Tables 1, II, and III, will show that in each case in 

 which nitrogen was applied as ammonium salts, the dry matter of the 

 plants contained higher percentages of nitrogen than when sodium 

 nitrate was employed. Maze (loc. cit.), in his water culture experiments, 

 obtained similar indications, the percentages of nitrogen being as 

 follows: — 



Source of nitrogeu N. in dry matter 



Ammonium salt 3"43°/q 



Sodium nitrate 3'17°/o 



Table IV. Percentage of Nitrogen in the Mixed Herbage of the 

 Rothamsted Grass Plots. 



1858—73. t 1856—1861. 



Pitsch also shows {loc. cit.) that in the great majority of cases the 

 ammonia plants contain higher percentages of nitrogen than the nitrate 

 plants. Further confirmation is afforded by a comparison of the per- 



