GROUPINGS AND GENERAL RELATIONSHIPS 13 



ation into roots, stem and leaves. Sometimes the entire 

 plant consists of a single cell, that is, is unicellular. In 

 other cases it may consist of a chain of cells united to form 

 more complex structures, though this is never the case with 

 bacteria, yeasts, or molds. The group Thallophyta has 

 three important subdivisions. The first is that of the algae, 

 forms containing green coloring matter or chlorophyll. 

 The second group is that of the fungi which differ from the 

 algae in that they do not possess chlorophyll. It includes 

 such forms as yeasts, molds, puffballs, mushrooms, mil- 

 dews, etc. The third subgroup is that of the Schizophyta 

 or fission plants in which multiplication is of some other 

 type than that of simple cell fission. One of the subdivi- 

 sions of this group is that of the Schizomycetes or bacteria. 

 In the following scheme of classification an attempt is made 

 to show the various important subgroups of the Thallo- 

 phyta. Those subgroups which contain organisms to be 

 studied in bacteriology are designated by bold-faced 

 type. 



GROUPS OF THALLOPHYTA SHOWING POSITION AND RELATION- 

 SHIPS OF BACTERIA, YEASTS, AND MOLDS 



Thallophyta. Simple plants, never differentiated into 

 roots, stems and leaves. 



A. Unicellular plants, multiplying by cell fission only. 



1. Without chlorophyll. Bacteria or Schizomycetes. 



2. With chlorophyll. Blue-green algae or Schizo- 



phyta. 



B. Unicellular or multicellular. Multiplying by means 



other than simple cell fission. 



1. Without chlorophyll, the fungi, including the 



yeasts, molds, mildews, smuts, rusts, puffballs, 

 mushrooms, etc. 



2. With chlorophyll, including the seaweeds, pond 



scums, water silks, etc. 



