46 



BOTANICAL GAZETTE 



[JULY 



experiments. The 



triangle 



represents the various cultures con- 



■ 



taining the fertilizer combinations, as is fully explained in fig. i 

 and the accompanying text. 



Under normal conditions, that is, without any toxic body present, 

 the greatest growth is found in those cultures low in phosphate and 

 about halfway between the nitrate and potash angles. 



This 



p„o 



5 



KoO 



Fig. 5. 



triang 



representation 



1 



growth 



in the 



uma 



greatest growth is diagramma 



marked 



When cumarin 



direction 



greatest 



may be diagrammatically shown by the circle marked cumarin 

 With quinone, this region of growth was shifted toward the potasl 

 angle, and with vanillin toward the nitrate angle, as illustrated ir 

 the diagram. 



