56 



OSWALD SCHREINER AND J. J. SKINNER 



TABLE V 



Effect of hypoxanthine on growth in cultures conlaining 8 p. p.m. of XH3 as nitrate 



FEBTILIZEB INGREDIENTS IN CULTUBE 

 SOLUTIONS 



GBEEN WEIGHT OF CULTUBE 



CULTURE NO. 



PsOs 



NH3 



KjO 



xanthine 



Wli-Vi inn r\ r» m 



hypoxanthine 





p. p.m. 



p. p.m. 



p. p.m. 



grams 



grams 



57 



0 



8 



72 



1.748 



2.150 



47 



8 



8 



64 



2.440 



2.772 



38 



16 



8 



56 



2.150 



2.470 



30 



24 



8 



48 



2.000 



2.628 



23 



32 



8 



40 



2.390 



2.692 



17 



40 



8 



32 



2.456 



2.850 



12 



48 



8 



24 



2.370 



2.640 



8 



56 



8 



16 



2.275 



2.450 



5 



64 



8 



8 



1.800 



1.920 



3 



72 



8 



0 



1.078 



1.100 



Growth in cultures icitli larger amounts of nitrates 



When the effect of the hypoxanthine in the series of cultures 

 already containing 16 parts per million of NH3 as nitrate is con- 

 sidered, it is found the effect is still less marked than either of 

 the above results. This is shown in Table VI, where the growth 

 with hypoxanthine, while still greater than the growth without 

 this ingredient, is nevertheless not so clearly marked as in the 

 two series of cultures already considered. The average increase 



TABLE VI 



Effect of hypoxanthine on growth in cultures containing 16 p. p.m. of XH3 as nitrate 





FERTILIZER INGREDIENT.S IN CULTURE 



GBEEN WEIGHT OF CULTURE 



CULTURE NO. 





SOLUTIO.NS 







NHj 



K2O 



Without hypo- 

 xanthine 



With 100 p.p.m. 

 hypoxanthine 





p.p.m. 



p.p.m. 



p.p.m. 



grams 



grams 



58 



0 



16 



64 



2.120 



2.224 



48 



8 



16 



56 



2.800 



2.500 



39 



16 



16 



48 



2.750 



2.900 



31 



24 



16 



40 



2.722 



3.059 



24 



32 



16 



32 



2.770 



3.094 



18 



40 



16 



21 



2.926 



3.000 



13 



48 



16 



16 



2.490 



2.500 



9 



56 



16 



8 



1.974 



2.100* 



5 



64 



16 



0 



1.270 



1.150 



