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MOSSES AND THEIR ALLIES 
fungi. Specialization is shown in the cells which gather and 
conduct water, the beginning of the absorptive and conductive 
systems of plants. There is also the beginning of a system 
for getting oxygen. The life history of a moss represents 
the alternation of generations, a generation which reproduces 
by spore (asexually), and one which reproduces by egg and 
sperm (sexually). The generation which bears spores is the 
sporophyte, and that which bears eggs and sperms, the 
gametophyte. 
QUESTIONS 
In what respects are mosses more highly developed than algae, fungi, 
and lichens? Why do mosses require so much moisture? Give the life 
history of a moss. 
REFERENCES 
Bergen and Caldwell, Practical Botany. 
Leavitt, Outlines of Botany. 
Smallwood, Textbook of Biology. 
