OUTLINE STUDY OF SEEDS AND SEEDLINGS. 21 5 



In the germination of a seed, the first part to begin growth is 

 the root. The squash plant is helped out of the seed-coat by 

 means of a little knob. One root only always appears first, and 

 no matter in what position the seed lies, the root wall take 

 a course vertically downward. After the appearance of the main 

 (or tap) root, the stem begins to grow. Branch roots do not 

 grow downward like the main root, but more nearly horizontal. 

 The root is covered in a definite region with numerous root hairs, 

 which never extend quite to the tip of the root. 



By careful questioning on the part of the teacher, the pupil 

 should be taught that the greatest need of the plant is water, that 

 the most abundant supply is in the soil, and that the plant needs 

 to be held fast where it can get water. Therefore, the best good 

 of the plant makes it necessary for the root to grow downward, 

 first to hold the plant fast, second to absorb water for the plant. 

 If the root did not grow downward (curving when necessary) 

 no matter in what position the seed is placed, then gardeners 

 and farmers would have laboriously to plant every seed root 

 downward or else man}' would perish on germination. 



By growing laterally, the branch (secondary) roots hold the 

 plant more firmly in the soil, and at the same time enable the plant 

 to secure water from a wider area. 



The fine white root-hairs are parts of the root by which it 

 absorbs the water from the soil. If they grew at the very tip of 

 the root, they would be liable to injury, as the root pushed its 

 way through the soil during growth. 



How THE Stem Lifts Itself into the Air. 



Watch carefully for the first signs of the planted seeds break- 

 ing the surface of the soil. How does the bean seedling break 

 ' the ground ? Does the tip of the stem appear first ? Do all the 

 different seeds planted break through the soil in the same way ? 

 Describe. Do all the seeds of the same kind break the ground in 

 the same manner? 



Rule a horizontal line across a sheet of pad paper to represent 

 the surface of the soil, and at the left make a drawing to show 

 how the bean seedling breaks through the ground. Save the 



