Latham : Assimilation of Sterigmatocystis 



239 



in the substratum, where the amount of nitrogen fixed may become 



negative, that is to say 



from which nitrogen 



may be used in 



metabolism ; (3) the amount of nitrogen entering into the com- 

 position of the felt remains relativ^ely the same in normal and stim- 

 ulated growths ; (4) the optimal stimulation from a carbohydrate 

 point of view is not marked in nitrogen fixation where there is a 

 gradual decrease in the amount caused to combine. These six 

 series are wholly consistent within themselves. 



Table I 



It may be seen by reference to Table I that with the control 

 crops, those under normal conditions and without stimulation, 

 there was found an increase of nitrogen over that of the initial 



