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AUGUSTO BONAZZI 



8.51 while the culture incubated twenty- three days gave a value 

 6.63 — of approximately equal magnitude. From these data we 

 can draw a very interesting set of figures if we consider the 

 actual ''ferment -power' ^ per day. The term ''ferment power'' 



10 20 30 



units of time 



Fig. 6. ♦ = value of 4 day period on 4 day basis; O = value of 4 day period 

 on 2 day basis (see text). 



as used by Pasteur and modified by Duclaux to include the time 

 element gives valuable indications as to the physiology of Azoto- 

 bacter (see table 17 and fig. 6). 



The term "ferment power" is here used to designate that 

 quantity of sugar consumed by the unit of dry cell substance in 

 the unit of time under the conditions of the experiments. This 

 concept leads us to the conclusion that during the early stages of 



