160 BOTANICAL GAZETTE [august 



tures containing creatinine, a difference of 19 milligrams in favor 

 of the creatinine cultures. 



Potassium. — The amount of potash stated as K 2 removed by 

 the plants in the total number of cultures was 760 milligrams in 

 the case of the normal cultures and 778 milligrams for the cultures 

 with creatinine. As with the phosphate, the creatinine cultures 

 removed a little more potash than the normal cultures, there being 

 a difference of 18 milligrams in favor of the creatinine set. 



Nitrogen. — The total amount of nitrogen stated as NH 3 removed 

 from the total number of solutions during the course of the experi- 

 ment was 560 milligrams for the normal cultures and 423 milligrams 

 for the creatinine cultures. The creatinine cultures though making 

 a larger growth used 137 milligrams less nitrate. 



Effect of creatine on growth 



Creatine is closely related chemically to creatinine, the latter 

 being the anhydride of creatine. Both probably occur in soils, 

 manures, and green crops, a discussion of which is given in the two 

 other papers referred to. Experiments in nutrient cultures with 

 creatine have been conducted similar to those with creatinine. 



The plants grew from April 22 to May 4. After the plants had 

 grown for several days, it was apparent that the effect of creatine 

 was very similar to that of creatinine. The leaves were broader, 

 and further developed than those of the normal culture. The roots 

 were longer and better branched. The plants growing in cultures 

 with creatine, which contained phosphate and potash but no nitrate, 

 were a great deal larger than similar cultures without creatine. 

 Like the creatinine, when small amounts of nitrate were in the fer- 

 tilizer mixture, the beneficial effect of creatine was not so marked, 

 and in the presence of larger amounts of nitrate creatine had no 

 additional effects. 



The total green weight of 66 cultures containing the fertilizer 

 salts only, that is the normal set, was 174.4 grams, against 186.8 

 grams for the 66 cultures containing 50 ppm. of creatine in addition 

 to the fertilizer salts. This is an increase for the creatine cultures 



1 



of 8 per cent over the normal cultures. 



Table V shows the effect of creatine on growth in a number of 



