io8 



BOTAXICAL GAZETTE 



FEBRUARY 



nitrogen leaves were in every case stiff and upright. By March 16 

 the "no phosphorus 1 ' series began to show the effect of the defi- 

 ciency. The "no potassium 1 ' series in the warm house showed the 



TABLE III 



Proportion of leaves (blade and sheath) and stems in 

 100 parts of total plants, based on green weight 



greatest lopping over on March 16. About April 1 the plants in 

 the cool house began to outstrip the plants in the warm -house in 

 their growth rate, and in particular in their tendency to maintain 

 an upright growth habit. The total amount of tissue formed at 



Fig. 3. — Nitrogen series, cool house: note vigorous upright condition of no. 85 

 as compared with sprawling condition of no. 23 (fig. 4). 



the higher temperature was about the same, but it was differently 



distributed, as will be apparent from the data given in table III. 



By April 19 all plants in the cool house had outstripped those in 



the warm house. The most striking difference between the two 



