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 algas. 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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