NOTE ON CKYPTOGAMS 



177 



NOTE. All the details of fertilization and of the development of 

 the generations are omitted from this book, because they are subjects 

 for specialists and demand more training in research methods than 

 the high -school pupil can properly give to plant study. Cryptogams 

 are perhaps as many as phenogams, and for this reason it has been 

 urged that they are most proper subjects for study in the school. 

 This position is untenable, however, for the best plant subjects for 

 youth are those which mean most to his life. It is said, also, that 

 they are best for the beginner because their life -processes are rel- 

 atively simple in many cases ; but the initial study of plants should 

 be undertaken for the purpose of quickening the pupil's perception 

 of common and familiar problems rather than for the purpose of 

 developing a technical knowledge of a given science. 



Tree ferns are inhabitants of the tropics. 

 They are often grown in choice greenhouses. 



