Suggestions for Laboratory and Field Work to Precede 

 Chapter Twenty 



1. Make a field study of liverworts and mosses, noting especially 

 conditions most favorable to them. Examine underground parts 

 as well as above-ground parts. 



In winter a visit to a conservatory or greenhouse will enable 

 students to see these forms in a growing condition. 



2. Specimens of liverworts may be secured in spring from moist 

 rocks along streams, from the soil in clover fields, and from trees 

 in moist woods. In Marchantia, study particularly the thallus, 

 rhizoids, growing region, cupules, gemmae, and reproductive 

 branches. 



3. Of the mosses, Mnium and Polytrichum are particularly 

 good to show protomena, rhizoids, stem, leaves, and reproductive 

 structures. Compare the vegetative plant body of a moss with 

 that of a liverwort in its relation to water, light, and air. 



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