u8 



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 ) 





p 



Culture no., treatment, and time of sampling 



Direct reducing 



sugars (as 



glucose ) 



44. 



24. 

 41. 



108. 



87. 



104. 



High N 4 p.m., April 24, 1918 warm 



High N 9 a.m., April 25, 1918 warm 



High P and N 3 p.m., April 25, 1918 warm. 



High N 6 p.m., April 24, 1918 cool 



High N 10 a.m., April 24, 1918 cool 



High P and N 5 p.m., April 24, 1918 cool.. 



Percent- 

 age Fa 



1599 

 19.83 

 10.62 



20.20 



23.17 

 25.08 



Total sugars 

 after mild 

 hydrolysis 

 (as glucose) 



Percent- 

 age total 

 leaf 



5.27 

 6.69 



346 

 6. 11 



6.44 

 759 



Percent 

 age Fa 



29.41 

 26.84 



18.55 

 45.79 

 36.99 



39-90 



Percent- 

 age total 

 leaf 



9.7i 

 905 



505 

 13.88 

 10.29 

 12.08 



8° 



W 



o 



< 



Z 



u 



u 



o 



< 



OS 



'- 



w 



u 



<X *i r> 



<ZH 



H S» t 



o ^ £ 



H C > 



O.I5252 

 O.I5342 

 0.06535 



o . 26007 



O.I8985 

 0.22I42 



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

 tions. Table XIII gives the proportion of skeletal material in 



