Introduction. 



One of the first questions a botanist asks about a plant is, 

 "Where did it grow," and the next is, "When and where did 

 you get it," Yet it is surprising how seldom these points are 

 noted, and how many collections are preserved without suffi- 

 cient data to guide us in the identification of the specimens. 

 If this book does nothing more than emphasize the importance 

 of observing these points it will do good. 



It will also aid in the appreciation of that new development 

 of botanical study, the science of Plant Ecology. It will teach 

 the novice how altitude, latitude, soil and environment affect 

 the vegetation of certain areas ; how certain plants are found 

 growing together because of the nature of the soil and of their 

 surroundings. If it also leads to the understanding of their 

 gradual adaptation to changed conditions it will give a broader 

 and more comprehensive view of plant morphology and lead 

 away from the mistaken idea that plants must and should con- 

 form to our artificial definitions, and make clearer the laws of 

 evolution. 



To feel that plants are living things, that individuality and 

 heredity are constantly struggling in them for ascendancy, 

 bringing about modifications which in course of time are suffi- 

 cient in amount and importance to create specific differences, 

 these are the underlying principles of the study of plants. 



That the love of Nature is gaining ground among us is shown 

 in many ways. The number of books and magazines dealing 

 with natural-history subjects in a popular way, increases yearly 

 to meet an increasing need. A constant demand exists which 



