INTRODUCTION 



BOTANY 



PRELIMINARY. 

 BOTANY is the Science which treats of Plants. 



A plant is a cellular body, possessing vitality, living by 

 absorption through its outer surface, and secreting starch. 



This is a definition to which, in the existing state of know- 

 ledge, there seems to be no objection. Others define a plant 

 differently. 



Linngeus distinguished a plant from an animal by its grow- 

 ing and living without consciousness (Vegetabilia crescunt 

 et vivunt. Animalia crescunt, vivunt et sentiunt] and he 

 abandoned the old differences of locomotion and local nutri- 

 tion which were supposed to be peculiar, the first to animals, 

 the second to plants. Both Jungius and Boerhaave defined 

 a plant to be a living body, attached to another body by some 

 part of itself, through which part it obtains and attracts the 

 materials for nutrition, growth, and life. Ludwig regarded the 

 power of locomotion in animals as their sole distinction from 

 plants. But it is impossible to deny the power of locomotion 

 to Brittleworts (Diatomacea) or young Algals (see Lindley's 

 Vegetable Kingdom, p. 14) . Multitudes of aquatic Thallogens 

 are produced and nourished without any fixed point of attach- 

 ment, and when motion has all the appearance of being 



VOL. T. B 



