STUDIES OF SPORE-PLANTS 233 



222. Cryptogams and Phanerogams. Spore-plants are 

 often called cryptogams, which means hidden reproduction, 

 and was given when their life-histories were not well under- 

 stood. The term phanerogams, applied to seed-plants, 

 means evident reproduction, and was applied because the 

 conspicuous flowers are obviously connected with reproduc- 

 tion. 



I. HIGHER SPORE-PLANTS: FERNS AND MOSSES 



The ferns and mosses, and their relatives, are distinguished 

 by the possession of structures which are similar to and per- 

 form the functions of the roots, stems, and leaves of seed- 

 plants. These are lacking in the lower spore-plants ( 235). 



FERNS 



223. General Structure of a Fern Plant.* Any common 

 kind or species of ferns may serve as material for illustrating 

 this study and for parallel laboratory work. The fern plants 

 are like the seed-plants in having roots, stem, and leaves 

 (also called fronds). The stem of our ordinary ferns is com- 

 monly on the surface or slightly buried in the soil ; but the 

 tree-ferns of tropical countries, often seen in greenhouses, 

 have upright stems. The prostrate stem (rootstock) of 

 ordinary ferns grows from a terminal bud, and since the stem 

 lives for many years and the leaves usually only one summer, 

 the stem is continually advancing and sending up new leaves 

 farther and farther away from the position of the first ones. 

 The stem may branch ; and since the older part of the stem 

 dies and decays, it frequently happens that the branches get 

 separated from the main stem and become separate plants. 



The root, stem, and leaf of ferns are similar in structure to 

 those of seed-plants. In the stems are vascular bundles con- 



* Concerning laboratory work on ferns : The teacher should provide 

 the students with materials for demonstrations or laboratory study of the main 

 points in the following description of ferns. See "Teacher's Manual." 



