88 THE ORIGIN AND EVOLUTION OF LIFE 



as chemical messengers cause interactions in other organisms. 

 With the simplest bacteria which live directly on the lifeless 

 world we find that most of the fundamental chemical energies 

 of the living world are already established, namely: 

 (a) the colloidal cell interior, with all the adaptations of col- 

 loidal suspensions, including 

 {[)) the stimulating electric action and reaction of the metallic 

 on the non- metallic elements; for example, the accelera- 

 tions by iron, manganese, and other metals. Some bac- 

 teria carry positive, others negative ion charges; 



(c) the catalytic messenger, or enzyme action, both within and 



without the organism; 



(d) the protein and carbon energy storage, the primary food 



supply of the living world. 

 Thus the chemical reactions of bacteria are analogous to those 

 of the higher plant and animal cells. 



Considering bacteria as the primordial food supply, it is 

 the invariable presence of nitrogen which distinguishes the 

 bacteria making up their proteins; nitrogen is also a large con- 

 stituent of all animal proteins. 



Percentage or Elements in the Proteins ^ 



Carbon 50.0-55.0 



Hydrogen 6.9- 7.3 



Oxygen I g. 0-24.0 



Nitrogen 18. 0-19.0 



Sulphur 0.3- 2.4 



Bacterial suspensions manifest the characteristics of col- 

 loidal suspensions, namely, of fluids containing minute gelat- 

 inous particles which are kept in motion by molecular move- 



^ Moore, F. J., 1915, p. 199. Nucleic proteins contain a notable amount of phos- 

 phorus as well. 



