Staphylococci 



y .--"^^ 



y /' 









./ 



Streptococci 



Pneumococci 





Typhoid bacilli 



Anthrax bacilli 





-s.-- 



Glanders bacilli 



Spirillum undula 

 (Showing Hagella) 



TYPES OF BACTERIA 



Cholera spirilla 



Spirillum rubrum 



United States Army Medical Museum 



Bacteria are divided into three main groups according to the general shape of the 

 cell: round-cell, or coccus, type, in which the cells cling together either in chains or 

 in clumps; rod-shape, or bacillus, type; and spiral, or spirillum, type. Some bacilli 

 and some spirilla move by means of cilia. Each group includes pathogenic, or disease- 

 producing, bacteria 



