CHAPTER VIII 
TAXONOMY 
DIVISION I.— THALLOPHYTA 
Plants, the greater number of which, consist of a thallus, a body 
undifferentiated into root, stem or leaf. The group nearest to the 
beginning of the plant kingdom presenting forms showing rudi- 
mentary structures which are modified through division of labor, dif- 
ferentiation, etc., in higher groups. 
SUBDIVISION I.— PROTOPHYTA (SCHIZOPHYTA) 
A large assemblage of “fission plants” comprising the bacteria 
and blue-green algte. In the simplest types no nucleus is present, 
but as we arise in scale through the bacteria and blue-green algae, 
there is to be observed an open granular, gradually growing to a 
crescentic, chromatin mass that may be called a nucleus. A common 
method of asexual reproduction is possessed by these plants whereby 
the cell cleaves or splits into two parts, each of which then becomes 
a separate and independent organism. 
I. SCHIZOMYCETES — BACTERIA 
Bacteria are minute, unicellular, colorless, rarely weakly red or 
green colored, non-nucleate vegetable organisms destitute of chloro- 
phyll. They serve as agents of decay and fermentation and are 
frequently employed in industrial processes. According to the vari- 
ous phenomena they produce, they may be classified as follows: (a) 
Zymogens producing fermentation; ( b ) Aerogens producing gas; (c) . 
Photogens producing light; (d) Chromogens producing color; ( e ) 
Saprogens, producing putrefaction; (/) Pathogens, producing disease. 
Physical Appearance of Bacterial Colonies and Individual Forms. 
Because of their minute size — a space the size of a pinhead may 
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