Suggestions for Laboratory and Field Work to Precede 

 Chapter Twenty-one 



1. Make a field trip to study ferns and their allies. Ferns are 

 common in rich woods and on moist cliffs. Equise turns may be 

 found along streams and railway embankments, and in swamps. 

 The club mosses occur in low grounds, in rich woods, and in moist, 

 sandy depressions along lake and sea beaches. Tropical forms 

 may be seen in conservatories and greenhouses. Note especially 

 the relative development of leaves, stems, and roots. Compare 

 them with the seed plants growing in the same habitats. Have 

 they any advantages over the mosses, liverworts, and algae that 

 live near them ? 



2. Examine growing plants and note how fern leaves unfold. 

 Note the sporangia and spores on the under sides of the leaves. 

 Plant some of the spores on moist soil in a flower pot and cover with 

 a glass plate. Examine the prothalli that develop from the spores. 



3. If field work is impossible, examine a collection of pressed 

 specimens of ferns and allied plants, in order to get an idea of the 

 great variety of forms belonging to these groups. 



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