lO INTRODUCTION 



4. Vegetable Physiology, the study of the action of liv- 

 ing plants and their organs, their mode of growth and re- 

 production, and their various movements for adjustment 

 to their surroundings, as the attraction of roots toward 

 moisture and of leaves toward light. 



5. Ecology, the study of plants in their relations to ex- 

 ternal conditions, or, to use a more convenient term, their 

 environment. This is one of the most interesting and 

 important of all the departments of botany, and presents 

 many points of direct practical concern to the farmer. 



6. Taxonomy, called also Systematic or Descriptive 

 Botany, the study of plants in their relationships to one 

 another. Its work is to note their resemblances and differ- 

 ences, and by means of these to classify or distribute 

 them into certain great groups called famihes or orders, 

 and these again into lesser groups of genera and species. 

 This work of classification was formerly considered the 

 chief end of the study of botany, which thus too often de- 

 generated into a mere mechanical drill in hunting down 

 plants and labeling them with hard names. The ten- 

 dency at present is to ignore this part of the subject 

 altogether, which is nearly as great a mistake as the old- 

 fashioned error of thinking that the study of botany con- 

 sisted merely in learning a string of hard words. One of 

 the chief pleasures to be derived from botanical studies, 

 for most of us, consists in being able to know and recog- 

 nize the various plants we meet with. The first thing we 

 all ask on seeing a new shrub or flower is, "What is it ? " 

 and this question can be answered satisfactorily only by 

 referring each to its proper class or order. 



7. Learn to know the Common Plants. — These five sub- 

 divisions make up the study of botany, as generally taught 

 in the schools. They apply to all plants, and the only 

 practicable way for most of us to learn them is by a study 

 of the common vegetable life about us. 



