CHAPTER XIV 
THALLOPHYTES (Continued) 
Myxomycetes and Bacteria (Thallophytes lacking food-making 
pigments) 
There are three groups of Thallophytes — the Myxomycetes, 
Bacteria, and Fungi — which are characterized by the lack of 
food-making pigments. Having no chlorophyll or other food- 
making pigments, they are unable to carry on photosynthesis and 
consequently must depend upon other organisms for their food. 
Many obtain their food from the decaying bodies of other or- 
ganisms, while others attack living organisms. 
As to how these plants arose, we are not certain. Although 
some are the simplest of plants, they must have been preceded by 
green plants, for otherwise there would have been no food for 
them. They are no doubt degenerate forms of green plants, 
having lost their food-making pigments as a result of their acquir- 
ing the habit of taking food from other organisms. As will be 
seen later in the study of these groups, the Bacteria have some of 
the features of the Blue-green Algae, while the Fungi present a 
number of features found in the Green or the higher groups of 
Algae. But for the Myxomycetes we have no definite suggestions 
of any relationships with other groups of plants. 
Being dependent plants, these Thallophytes are supposed to 
have evoluted backward, rather than forward. The Fungi, the 
most complex of the group, present nothing new over the Algae 
in the way of evolution. To the evolutionists these groups offer 
very little that is of interest. They concern us chiefly because 
of their economic importance. 
Myxomycetes (Slime Molds) 
The plant body of the Myxomycetes, commonly called Slime 
Molds, consists of a large slimy mass of protoplasm not enclosed 
by cell walls, and hence the term myxomycetes from myzos 
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