CHAPTER XVII 
MOSSES, LIVERWORTS, AND FERNS 
248. Introductory. The mosses belong to the second great 
division of the plant kingdom, the bryophytes, which means 
“moss plants.” All small, green plants are commonly called 
mosses, but when we discover what kinds of plants mosses 
are, we shall see how incorrect such a general use of the 
term is. The bryophytes also include another group, the liver- 
worts, which are peculiar and infrequently noticed plants. 
The mosses, on the contrary, are extremely abundant and 
grow in almost all kinds of places. The ferns (pteridophytes, 
which means “feather plants,” or “fern plants”) constitute 
the third great division of the plant kingdom and will be con- 
sidered after the bryophytes. It is so much easier to get clear 
notions of the bryophytes by a study of the mosses, that we 
shall give our chief consideration to them, rather than to the 
liverworts, which are simpler in some ways but less common 
and less easily studied than mosses. 
249. The moss plant. Careful observation of any common 
moss will enable one to see that it has green, leaf-like struc- 
tures arranged around a very small stem. Sometimes also 
there appears upon this leafy stem a slender stalk with a 
swollen, pod-like tip, or capsule (fig. 203, C). In this tip many 
simple asexual spores are formed, and if we follow the life 
round of the moss, beginning with the development of one of 
these spores, we shall get a good notion of the nature of the 
structures of the moss plant. 
Upon the germination of the asexual spore there grows 
from it a filament, or thread, which looks so much like the ale 
that it is often extremely difficult to distinguish it from them. 
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