CLASSIFICATION OF BACTERIA 107 



II. Family: Bacteriaceae Migula. 



The cells are cylindrical in shape. They vary in length 

 from short, almost spherical bodies to very long rods. Cell 

 division takes places in one direction in a plane perpendicular 

 to the long axis of the cell. Some of the members of this 

 family remain attached together, forming threads, while 

 others separate from each other soon after fission. 



Genus : Bacterium Ehrenberg. 



The cells are cylindrical, of longer or shorter length. 

 Threads are frequently formed. The cells do not possess any 

 organs of locomotion. Endospores are produced in some 

 few species, but in the majority no such formation occurs. 

 It is possible that endospore formation occurs only under 

 certain environmental conditions. 



Genus : Bacillus Cohn. 



The cells are cylindrical, of longer or shorter length. The 

 rods are sometimes oval in shape. Cells are motile and pos- 

 sess flagella which are distributed over the entire surface. 

 Endospore formation occurs with marked regularity. The 

 bacteria in this genus are motile only during certain periods 

 of their life. This period varies greatly in length and occurs 

 only in the vegetative stage. 



Genus : Pseudomonas Migula. 



The cells are cylindrical, of longer or shorter length. The 

 cells are motile and possess polar flagella. These flagella 



