CHAPTER XVI 
BRYOPHYTES (MOSS PLANTS) 
Liverworts and Mosses 
General Discussion. —In the study of the Myxomycetes, 
Bacteria, and Fungi, not much attention was given to evolution- 
ary tendencies, for these groups are supposed to be degenerate 
forms ard have contributed nothing of importance in the way of 
evolution. But in taking up the study of the Bryophytes, we 
return to the study of evolution which will be emphasized 
throughout the remaining groups, the aim being to see how 
Flowering Plants could have originated. 
The Bryophytes include two large groups of plants — Liver- 
worts (Hepaticae) and Mosses (Musct) — although the term 
refers to Mosses. The Mosses are more conspicuous and more 
familiar to most people than the Liverworts, but they are no 
more important in the study of evolution. 
The Bryophytes are of practically no economic importance. 
They are of very little value for food and rarely harm other 
plants. They make their own food and therefore do not need 
to prey upon other plants. The only reason for studying them 
is that they have contributed to evolution, and a knowledge of 
them is necessary for an understanding of the higher plants. 
The Bryophytes are supposed to have originated from the 
Algae, and the advancements made by the Algae, such as the 
establishment of multicellular plant bodies, food-making by 
photosynthesis, development of gametes and sex organs, and the 
differentiation of gametes and other cells, are resumed and some 
of them carried farther by the Bryophytes. 
Most Algae live in the water while the Bryophytes in most. 
part live on the land. The Bryophytes are considered the first 
and most primitive land plants. The Algae are exposed to water 
while most Bryophytes are exposed to the drying effects of the 
air. Most Algae soon die when removed from the water and 
exposed to the air, for they are not protected against loss of water 
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