STUDIES ON AZOTOBACTER CHROOCOCCUM BEIJ. 



343 



solution was then used for the determination of the residual 

 sugar. The results are presented in tables 9 and 10. 



Expressing these values in terms of cubic centimeters of gas in 

 the total volume of the flasks at 0°C. and 760 mm. we have the 

 result shown in table 10. 



Fig. 3. a, culture flask; b, manometer tube (Hg rose to atmospheric pressure 

 when evacuated); c, evacuation tube and gas collector connection; x, paraffin 

 coating on rubber stopper. 



If now we consider all the oxygen disappeared to be used in a 

 process of combustion such as is expressed in equation 2 on 

 page 338, we have the data given in table 11. 



In the above data we find confirmation of the hypothesis 

 expressed above. Azotobacter utilizes the sugar first in the 

 building up of its cell substance and the preparation of non- 

 reducing substances; and slowly digests these "stores" of car- 

 bonaceous material in the process of later development in the 



