4 Agricultural Bacteriology. 



creasing in size. The bacteria increase in number in a 

 similar way, each cell dividing into two at each division. 

 The mother cell disappears and two daughter cells are 



FIG. 2. DIVISION OF BACTERIA. 



The bacteria increase in numbers through the divi- 

 sion of each cell into two cells. (After Novy.) 



formed, which in turn soon become mother cells and 

 thus the process is repeated. 



Arrangement of cells. Each kind of plant can be rec- 

 ognized because the cells forming it are arranged in a 

 certain definite way, different from the arrangement of 

 the cells in all other plants. The arrangement of the 

 cells of those kinds of bacteria that cling together after 

 the cell has divided often enables the experienced bac- 



A B c 



FIG,. 3. ARRANGEMENT OF BACTERIA. 



A, streptococci; B, sarcina; C, staphylococci. (After 



Novy.) 



teriologist to recognize different types. The cells may 

 be arranged in long or short chains. Such aggregates 

 of cocci are known as streptococci ; clusters of cocci re- 

 sembling bunches of grapes are called staphylococci. 

 Still other forms of cocci divide in such a manner as 



