338 



AUGUSTO BONAZZI 



represents only the final changes, we are in a position to estimate 

 the quantity of CO2 which should have been formed in the 

 process (table 3). 



CeHisOe + 6O2 ^ 6 CO2 + 6 H2O (2) 



The final result of this experiment is therefore to show that 

 more carbon dioxid is formed and more sugar consumed than 

 can be accounted for by the amount of oxygen consumed. 



The solution in the particular flask was the seat of vigorous 

 development, beginning with the formation of a ring at the point 

 of air-glass-solution contact, slowly clouding the whole solution 

 and later sinking to the bottom of the flask in the form of a 

 heavy deposit exhibiting the gray-brown pigmentation char- 

 acteristic of Azotobacter. 



The quantity of sugar unaccounted for may well have been 

 found in the cell body and secretions had an effort been made to 

 account for the whole. Since this was not done we are only 

 justified in assuming such a possibility. That some secondary 

 actions do take place in a culture of Azotobacter is shown by the 

 presence of 96.4 mgm. CO2 in excess of the theoretical amoimt. 

 We may safely assume at present that this quantity of carbon 

 dioxid is derived from a process of intramolecular respiration. 

 A proof of this may be found in a later part of this paper, under 

 the heading of Autophagy. This assumption is also in agree- 

 ment with the equation of Duclaux for aerobic organisms, and is 

 substantiated by the following experiment. 



Experiment 4-6. A large Fernbach flask fitted with the attach- 

 ments shown in figure 2, received 100 cc. of a solution of the 

 composition shown below: 



