PLANTS. 43 



aimlessly fluttering, swaying, and bending, but are 

 changing their positions to get as much air and 

 light as possible. Some plants, such as sunflow- 

 ers and field peas, are great lovers of light. 

 They bend the upper parts of their bodies toward 

 the sun, and follow it in its daily course. They do 

 this so that their leaves and blossoms may get a 

 large amount of light and heat. Others, such as 

 poplar trees, are so made that their leaves flutter 

 in the slightest breeze, thus presenting first one 

 side then the other, to the air and light. Such 

 plants do not have as many leaves as those that 

 have less movement. Each leaf does a large 

 amount of work, hence there is a saving in the 

 amount of exposed surface. 



Besides movement in one place,- plants such as 

 ferns, Solomon's seal, blood-root, and many others, 

 move slowly from place to place. They do so by 

 means of their underground stems. Such stems 

 grow horizontally in the ground in the direction of 

 the most plentiful supply of food. At one end of 

 the underground stem is a large bud. This bud, in 

 growing, pushes continually forward, while the 

 opposite end gradually dies away. All along the 

 stem are lateral buds. These yearly send up 

 branches or leaves for the necessary supply of air 

 and light, and the production of seeds. Such 

 plants are perennials, and live the longest; in fact, 

 they practically never die, except in cases in which 

 the underground stem is destroyed. They simply 



