n8 



BOTANICAL GAZETTE 



FEBRUARY 



In order to determine whether or not the material thus extracted 

 by i per cent NaOH contained any forms of P not precipitated by 

 magnesia mixture, the phosphorus was determined in the insoluble 

 residue. Similarly total N determinations were made in the in- 

 soluble residue from another set of determinations. The difference 



Fig. 15. — Influence of extra heavy supplementary P fertilization on heavy N 

 fertilization: no. 41, heavy N and heavy P (warm house); no. 125, heavy N and 

 extra heavy P (cool house); no. 104, heavy N and heavy P (cool house); no. 63, 

 heavy N and extra heavy P (warm house). 



between total P (or N) soluble in 1 per cent NaOH gave the P (or N) 

 present in the NaOH extract. 



TABLE VI 



Effect of temperature on accumulation of soluble carbohydrates in barley 

 leaves (results of analysis of f 2 ) 



Tables VI-XII contain the results of the different determina- 

 tions. Table XIII gives the proportion of skeletal material in 



