100 



BOTANY 



The young seedling in this case responded to the influence of the 

 stimulus of light so as to grow out finally through the hole in the 

 box into the open air. Make this experiment, and see if you get 

 the same result. Vary the apparatus in any manner you can, and 

 plant some other seeds or grains. 



This experiment shows that another factor besides gravity influ- 

 ences the stem to grow upward. This growth of the stem to the 



Two stages in an experiment to show that green plants grow toward the light. 



light is of very great importance to a growing plant, because, as 

 we shall see later, food-making depends largely on the amount of 

 sunlight the leaves receive. 



Structure of a Bud. — If we cut a head of cabbage so that the 

 knife blade cuts through the long axis of the stem, we find that the 

 stem is much shortened or dwarfed, and that the leaves are so 

 placed as to cover it entirely. The cabbage is a big bud. If 

 we carry out our definition of a bud, starting with what we have 

 seen in the cabbage, we might say that a bud is a very much 

 shortened branch, or in reality '' the promise of a branch." 



