THE 13 A C T E R I A L N U C L H U S 65 



During the process ot genninaticMi the cell increases in size, except in the 

 case of myxobacteria which tend rather to diminish, the nucleic acid content 

 increases, and the nuclear material becomes large and readily stainable. This 

 is the period of the lag phase of the culture. In the logarithmic phase, which 

 immediately follows, the bacteria at first divide by simple fission alone, but 

 later this method is accompanied by others more complex, and eventually 

 the resting nucleus is restored. 



Fig. 26 

 THE GERMINATION OF THE RESTING STAGE 



A . The spore of a rough bacillus. 



B. The microcyst of Cytophaga sp. 



C. The resting cell of Bad. colt. 



The process is similar in each case. The wall may be shed or absorbed. The vesicular 

 nucleus is transformed into one or more bar-shaped bodies and these divide to give the 

 vegetative nucleus. 



E. THE SPHERICAL VEGETATIVE NUCLEUS 

 (7, 10, II, 17, 21, 26, 42, 50) 



The exact behaviour of the nucleus of the corynebacteria, mycobacteria 

 and cocci at cell division has not been recorded. It appears to be a simple 

 sphere, even when it attains to a size comparable with that at which the 

 double rod-shape of the primary nucleus of eubacteria may distinctly be 

 ,resolved by the microscope. In the reduction process which precedes the 



