CHAPTER XII 
BRYOPHYTES 
LESSONS XLVI AND XLVII 
The moss plant 
WHEN the asexual spores of the moss plant develop they 
produce a thready or filamentous growth—the protonema— 
which is not unlike some Alge. This grows in damp places, 
such as wet earth and decaying timber, and appears as a 
green coating. Sometimes from the cells of the protonema 
there grow small buds, which enlarge, finally becoming the 
leafy shoots of the moss plant. 
Vegetative structures.—(a) Protonema. After noting 
its general appearance, mount and study, and make a sketch 
showing the general structure. Are filaments all of one 
kind? How can you tell whether all are equally vigorous? 
Does the protonema differ from the filamentous Alge? If 
any buds of leafy shoots are present, make sketches showing 
their relation to the protonema. If your material is espe- 
cially favorable, show stages in the development of the leafy 
shoot from the bud. 
(b) The leafy shoot. Observe the arrangement of stem, 
leaves, and rhizoids. Sketch in detail a few cells from the 
leaf. How do you account for the different kinds of cells 
composing the leaf? 
Sexual reproduction.—(a) Antheridia and sperms. At 
the tops of some leafy shoots the leaves are spread out as 
an inverted umbrella, and at the tip of the stem, surrounded 
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