STUDIES ON AZOTOBACTER CHROOCOCCUM BEIJ. 



339 



Deep well water 250.00 cc. 



K2HPO4 0.05 gram 



Glucose 5.00 grams 



Ca(N03)2 + 4H2O 0.316 gram 



Calcium carbonate was added in the quantity of 0.5 gram. 



The total volume of the apparatus was of 2666 cc. and the 

 addition of the solution left 2566 cc. of air space. After sterili- 

 zation and inoculation with a pure culture of Azotohader chro- 



FiG. 2. a, culture flask; 6, d, e, gas collecting chain; c, mercury valve; z, paraflBn 

 and plaster of paris seals over ground glass joints. 



ococcum the apparatus was incubated at about 25°C. for fifty- 

 two days, after which period a gas analysis was made. Com- 

 paring the results obtained at the end to the values at the start 

 of the experiment we may calculate the gas exchanges in the 

 culture as shown in table 4. 



