404 PHYSIOLOGY OF BACTERIA 



To show graphically the meaning of this, Fig. 42 has 

 been used which represents the growth of Ps. fluorescens 

 after data obtained by Muller (1903). The dotted 

 lines in this curve illustrate the wrong assumption 

 made in the computation of the generation time at this 



Fig. 42. — Growth curve of Pseudomonas fluorescens. For the explanation 

 of the dotted and thin lines, see text. 



stage from the customary formula. It is impossible, 

 however, to compute generation times if we assume 

 an arithmetical increase as shown by the thin straight 

 lines, which represent the arithmetical averages. 



III. THE FERMENTING CAPACITY OF THE SINGLE CELL 



The various means of obtaining experimentally fer- 

 mentation without growth have been mentioned on p. 

 102. It is also possible, however, to eliminate the 

 disturbing factor of the multiplication of cells during 



