Elementary Plant Physiology 



CHAPTER I. 



INTRODUCTORY. 



THE plant is a living thing, an organism, which in its structure 

 shows a design appropriate to the nature of its functions, which 

 exhibits well-defined purposes in its actions, and which directs 

 all of its performances in accordance with the nature of impres- 

 sions received from external forces, or set up within its own 

 body. 



The course of .observations outlined on the following pages 

 is designed to enable the student to analyze the relations 

 between the structure and functions of the more impprtant 

 organs, attention being given chiefly to the higher plants, since 

 in them organs and functions attain their highest differentia- 

 tion ; to demonstrate the nature and purpose of the more im- 

 portant functions ; to follow some of the adjustments made by 

 the plant in the performances of its functions, changes in form 

 or structure in response to alterations in its environment ; and, 

 lastly, to delineate the correlations or intimate interrelations 

 existing among all of the organs of a plant, in accordance with 

 which any modification of the action of one is followed by 

 alterations in the functional performance of others. 



The following practical recommendations are made for the 

 successful accomplishment of the work outlined : 



