BOOK III. 

 PHYSIOLOGICAL BOTANY. 



INTRODUCTION. 



For the continual existence of plants on the earth, they 

 must first support their own lives for some time and must 

 next reproduce their kinds. 



That department relating to the maintenance of their 

 •own lives we term Physiology of Nutrition, and that relat- 

 ing to reproduction Physiology of Eeproduction. 



CHAPTER I. 



PHYSIOLOGY OF NUTRITION. 



In order to support their living functions, plants must 

 ■constantly receive proper food and must convert this into 

 bodily substances, because they consume continually the 

 latter for the performance of every function. These func- 

 tions are accomplished by the aid of several external forces 

 .such as light, temperature, etc. 



Section 1. NUTRITION PROPER. 

 1. TRANSPIRATION. 



If a tightly closed cylinder containing two or three 

 weighed leaves of the Tonasu and a dish of dry calcic 

 chloride of known weight be examined after exposing it to 

 "the sun for a few hours, it will be found that the leaves will 



