2 PRACTICAL BOTANY 



thousands of individuals. We cannot enumerate all the kinds 

 of places in which plants find lodgment and grow. They 

 occur in all the seas, as well as in the fresh waters, on every 

 kind of soil from the wettest swamps to arid deserts, on 

 rocky cliffs and the bark and leaves of trees. Microscopic 

 forms sometimes occur in myriads in the blood of animals, 

 and most soils teem with them to the depth of several inches 

 below the surface. 



It is a notable fact that some plants are the smallest and 

 others the largest of living beings, and it is evident that 

 plants are on the whole by far the most conspicuous of living 

 things. 



2. Plants and animals. A little thought about the things 

 upon which common animals feed will show that plants 

 directly or indirectly supply food for animals. Many animals 

 get their food directly from living plants, in the form of roots, 

 leaves, seeds, fruits, etc., and these are called herbivores 

 (plant eaters). Those animals called carnivores, which eat 

 the flesh of other animals, are dependent upon plants, since 

 their prey are plant feeders or may live upon those that are 

 plant feeders. In one way or another all animals are dependent 

 upon plants for food. 



3. Plants and the industries. Man is also directly or in- 

 directly dependent upon plants for his food. His animal food 

 is indirectly derived from plants, his bread is made from the 

 seeds of plants, and there is a constantly growing list of foods, 

 spices, and flavors that are prepared from roots, stems, leaves, 

 seeds, and fruits. 



Much of the work in which men are engaged is performed 

 by domesticated animals as beasts of burden, or is concerned 

 with rearing domesticated animals or growing plants for the 

 market. These animals could not be cared for were it not pos- 

 sible to feed them with the products of domesticated plants, 

 and many of the kinds of work for which beasts of burden 

 are used would not exist were it not for the need of growing 

 plants for the world's uses. 



