CONCLUSION* 321 



subject. But this prosecution of the science must 

 remain for the research of others. Such desiderata 

 will always be an inducement to those engaged in the 

 study or cultivation of plants, to advance physiolo- 

 gical knowledge, and complete the imperfect sketch 

 herein-before given. 



By attending to the appearances of plants in every 

 stage of their growth, and marking the changes which 

 take place as they pass from one state to another, 

 thereby tracing effects to their causes, is the only way 

 of gaining a complete knowledge of the phenomena 

 of vegetation ; and, when thus attained, every mani- 

 pulation to which plants have been, or may be sub- 

 jected, will be readily and unerringly applied. 



The principal features of the book will be found 

 to be descriptions of the organs of plants the 

 proper distinctions of stems and roots, which have 

 not been before defined with sufficient accuracy the 

 constitutional structure and development of bulbs and 

 tubers the progressive growth of new wood and 

 bark, and other processes of vegetation, as exemplified 

 in trees and shrubs. 



A few practical essays are added on the principal 

 operations of the gardener, woodman, and husband- 

 man, showing the application of physiological know- 

 ledge, and serving as proofs of various assertions 

 made in some of the foregoing sections. 



In arriving at the various conclusions stated in the 

 foregoing pages, besides our own practical tests of 

 many previously published opinions, we have to 



Y 



