14 Manual of Veterinary Microbiology. 



II. Organization of microbes. 



Structure and chemical composition. — The structure 

 of microbes may be compared to that of a cell with- 

 out nucleus. The existence of the latter is not gener- 

 ally admitted, although some authorities believe they 

 have observed such a structure. 



The content is a kind of protoplasm which Nenki 

 has designated by the name of mycoprotein, a homo- 

 geneous, or sometimes granular, substance generally 

 devoid of color. Under certain circumstances it may 

 contain brilliant corpuscles (spores), starch grains (in 

 the Sarcina), and granules of sulphur (Beggiotoa). 



The periphery is formed by a thin and flexible, or 

 thick membrane, the nature of which is not well 

 known. Most authors look upon it as a carbo-hydrate 

 allied to cellulose ; its resistance to acids and alkalies 

 seems to support this view. Others regard it as a 

 layer of mycoprotein difierentiated from the proto- 

 plasm. 



Sometimes this membrane emits vibratile cilia ; at 

 other times it is surrounded by a zone of a mucilagi- 

 nous aspect, capable of swelling up in water and form- 

 ing a transparent capsule to the germ (pneumococcus). 



III. Situation and distribution of germs in nature. 



The part which these beings play in nature being 

 known, it is easy to understand that they should be 

 found wherever there is organic matter to be reduced. 

 We find them, indeed, pullulating in all places where 

 there are no special conditions prejudicial to their life. 

 We will notice their distribution in the most impor- 



