PART III 



SYSTEMATIC BOTANY 



CHAPTER XVIII 

 CLASSIFICATION OF PLANTS 



In the preceding chapters we have investigated the 

 structures and functions of the organs which constitute a 

 plant ; the development of plants ; and their perpetuation. 

 In the course of our study we have met with many indi- 

 viduals, and occasionally analogies and differences have 

 been pointed out. But, so far, no general attempt has 

 been made to classify and arrange the two hundred thou- 

 sand or so members of the vegetable kingdom. How are 

 we to discover the basis of a satisfactory classification ? 

 The question obtains its most interesting solution in a 

 review of the history of botanical science. 



History of systematic botany. There is little doubt that 

 in the early dawn of civilization the culture of plants was 

 studied from the utilitarian point of view : by the agri- 

 culturist to provide food for himself and his flocks and 

 herds, and by the physician to prepare useful medicines. 

 Among later nations, and especially among the Greeks 

 and Romans, the subject assumed a new aspect : attempts 

 were made to systematize the vegetable kingdom from the 

 data and facts which had accumulated and been recorded 



