STUDIES ON AZOTOBACTEE CHROOCOCCUM BEIJ. 



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is worked over by the cells during the early stages of cultivation 

 and is then slowly utihzed by the cells in their later develop- 

 ment, during that period when the sugar curve runs about 

 parallel to the asymptote (to the axis X). 



In another experiment the following data were obtained, 

 corroborating the above statement. 



X* 



rime in da\js 



Fig. 4 



Experiment SI. Sugar consumption in large petri dishes of 

 20 cm. diameter: 



Sugar consumed 



Consumed per day during periods 



FIRST 5 DATS 



mgm. 



316.7 

 63.0 



NEXT 5 DATS 



mom. 



0.0 

 0.0 



Keeping in mind the fact that there are very few cells active 

 during the first five days, the number in fact being negligible 

 during the very first day or two, we can see that the first value is 

 much more than 63 mgm. of sugar consumed per day.* 



* Here it may be well to keep in mind the mathematical interpretation of 

 bacterial growth presented by Duclaux and discussed by him in volumes 1 and 

 2. This interpretation was later included by Rahn in his treatment of the fer- 

 mentive capacity of a single cell. Mich. Res. Bui. 10. 



