6 HOW PLANTS GROW, 



6. leaves (Fig. 4, I, I) are generally flat and thin, green bodies, turning one face 

 upwards to the sky, and the other downwards towards the ground. They make 

 the Foliage. 



7. The Plant in Vegetation, We see that a plant has a body or trunk (in scien- 

 tific language, an axis), consisting of two parts, — an upper and a lower. The 

 lower is the Boot : this fixes the plant to the soil. The upper is the Stem : this 

 rises out of the ground, and bears leaves, which are hung out on the stem in the 

 light and air. The root takes in a part of the plant's food from the soil : this the 

 stem carries to the leaves. The leaves take in another part of the plant's food 

 from the air. And in them what the roots absorb from the ground, and what they 

 themselves absorb from the air, are exposed to the sunshine and digested ; that is, 

 changed into something proper to nourish the plant. For there is lio nourishment 

 in earth, air, and water as they are ; but vegetables have the power of making 

 these into nourishment. And out of this nourishment it prepares, the plant makes 

 more growth. That is, it extends the roots farther into the soil, and sends out 

 more branches from them, increasing its foothold and its surface for absorbing; 

 while, above, it lengthens the stem and adds leaf after leaf, or shoots forth branches 

 on which still more leaves are spread out in the light and air. 



8. So the whole herb, or shrub, or tree, is built up. A tiny herb just 'sprouted 

 from the seed and the largest tree of the forest alike consist of root, stem, and 

 leaves, and nothing else. Only the tree has larger and more branching stems and 

 roots, and leaves by thousands. 



9. The Plant in Eeprodnetion. After having attended in this way to its nourish- 

 ment and growth for a certain time, the plant sets about reproducing itself by seed. 

 And for this purpose it blossoms. Many plants begin to blossom within a few 

 weeks after springing from the seed. All our annuals, of which the Garden Morn- 

 ing-Glory (Fig. 4) is one, blossom in the course of the summer. Biennials, such 

 as the Carrot, Parsnip, Mullein, and the common Thistle, do not flower before the 

 second summer ; and shrubs and trees, and some herbs, do not begin until they are 

 several years old. 



10. The object of the Flower is to form the Fruit. The essential part of the 

 fruit is the Seed. And the essential part of a seed is the Germ or Embryo it con- 

 tains. The Germ or Embryo is a little plantlet in the seed, ready to grow into 

 a new plant when the seed is sown. Let us notice these organs one after the other, 

 beginning with 



