2 INTRODUCTION 



indirectly dependent upon plants. The earliest "botan- 

 ical" interests were naturally in plants as food. But 

 it must have been discovered early in the history of man- 

 kind that some plants were not only not good to eat, but 

 positively poisonous, causing sickness or even death; 

 while others produced marked physiological effects, acting 

 some on one part of the body, some on another, like medi- 

 cine, and thus was early developed the study of plants 

 in order to ascertain their medicinal properties, and 

 their value in the treatment of diseases. This interest is 

 still reflected in the Spanish name for a drug store — 

 hotica. 



2. Relation of Plants to Man. — Thus we see that the 

 primary reason for our being interested in plants at all 

 was because they are intimately related to our physical 

 existence and well-being. As civilization advanced, 

 other uses for plants and plant products were discovered, 

 and thus other reasons for being interested in them. 

 They furnish all the wood of the world, and one has only 

 to consider for a moment how absolutely dependent we 

 are on wood, to realize still more vividly the intimate 

 relation between the life of plants and that of man him- 

 self. Our houses and furniture are of wood, our food 

 (the product of plants) is shipped in wooden boxes, 

 crates, and barrels, over rails supported by wooden ties; 

 most of the paper in use is made of wood pulp, and 

 innumerable articles in daily use — lead pencils, tool 

 handles, many musical instruments, et cetera — are made 

 largely of wood. Surely, it would be rather strange 

 if we did not have some interest, at least, in objects 

 so closely related to our daily lives, our welfare, and our 

 happiness. 



