OF TOT 



foil? W 



MICROBES A 



we have now to consider, may be assigned indifferently 

 to one or the other kingdom. 



Bory de Saint- Vincent, a naturalist belonging to 

 the early part of the century, and after him Hseckel, 

 have attempted to evade this difficulty by creating 

 between the animal and vegetable kingdoms an inter- 

 mediate kingdom, which they have named Protista, 

 indicating thereb3^ that it includes the first animals 

 which in the geological ages appeared on the earth's 

 surface. This kingdom of Protista includes the fol- 

 lowing groups, starting from the simplest and going 

 on to those which are more complex : 



*1. Monera (or Microbes, strictly so called; Schizouiycetes, Bac- 

 teria, Vibriones, ( tc.). 



2. Amorphous Rhizopoda (or Amoebae). 



3. Grega.'-imdae. 



4. Flagellata. 



5. Catallacta. 



6. Infusoria. 



7. Acinetae. 



8. Labyrinthulae. 



9. Diatomace^B. 

 *10. Myxomycetes. 

 *11. Fungi. 



12. Thalamophnra (Foraminifera or Rhizopoda with a calcareous 



skeleton). 



13. Radiolaria (or Rhizopoda with a silicious skeleton). 



The groups marked with an asterisk are those 

 which we propose to study in this work. For the 

 most part, the organisms assigned to them resemble 

 plants in their general characters. They are parasites 

 which derive their nutriment from other living beings. 



For this reason, many of these organisms are the 



