xii INTRODUCTION 



actively alive. We do not observe directly efforts that they 

 are making to accomplish their life work. It is only by 

 careful watching and observing that we can even begin to 

 obtain any conception of their actual activities. On this 

 account, it is especially necessary to keep in mind the fact 

 that the plant is a living thing. 



3. Life-History. Each and every living thing has what is 

 called a life-history ; /.<?. there is a certain beginning of its 

 own separate life, which runs through certain stages, and 

 there is finally an end to the life of that separate individual 

 at least ; i.e. it dies. This sequence of events from birth on 

 to death is the life-history. With an ordinary flowering plant 

 the life-history of the independent individual begins with the 

 germinating seed, goes through the stages of seedling, mature 

 plant, blossoming, fruiting, and ends with the mature seed. 

 The parent dies, living on only in its offspring. Every plant, 

 being a living thing, has a certain definite life-history, and 

 this must be borne in mind throughout the work. 



4. Struggle for Existence. We ordinarily think that a 

 plant simply grows and do not consider it a matter needing 

 any forethought or trouble of any kind. But when we come 

 to look at plants carefully, we find that forethought, or in other 

 words, provision, exists by means of which seeds of different 

 plants have a chance to get to favorable places for germina- 

 tion ; that when there they may be able to hold their own 

 to a certain degree, and not be crowded out by their neigh- 

 bors ; that certain ones can protect themselves against graz- 

 ing animals ; and that in every way each plant tries to obtain 



