. Botany for young people and common schools. How plants grow, a simple introduction to structural botany. With a popular flora, or an arrangement and description of common plants, both wild and cultivated. Botany. 22 HOW PLANTS GROW FROM THE Pea (Fig. 42), and of all such plants, is dicotyUdonous, that is, has a pair of cotyledons, or seed-leaves, which is what the word means. Therefore all such plants are called Dicotyledonous Plants. 49. Pine-trees, and plants like them, generally have more than two cotyledons, in a circle ; so their embryo is said to be i^hj- cotyUdonous ; meaning &
. Botany for young people and common schools. How plants grow, a simple introduction to structural botany. With a popular flora, or an arrangement and description of common plants, both wild and cultivated. Botany. 22 HOW PLANTS GROW FROM THE Pea (Fig. 42), and of all such plants, is dicotyUdonous, that is, has a pair of cotyledons, or seed-leaves, which is what the word means. Therefore all such plants are called Dicotyledonous Plants. 49. Pine-trees, and plants like them, generally have more than two cotyledons, in a circle ; so their embryo is said to be i^hj- cotyUdonous ; meaning " with several or many ; Fig. 49 is a ma2:nified view of a Pine-seed, divided len^jthwise, and showing the long and straiglit embryo lying in the middle of the albumen. The slender lower part is the radicle or stemlet; the upper part is a cluster of cotyledons or seed-leaves, in a close bundle; three of them can be seen as it lies, and there are as many more behind. Fig. 50 is this embryo as it comes up from the seed, its cotyledons (six in number) expanding at once into a circle of slender, needle-shaped leaves. 50. It is a pity these three words are so long; for the pupil should fix them thoroughly in his memory; because these differ- ences in the embryo, or plantlet in the seed, run through the whole life of the plant, and show themselves in many other dilferences which very strikingly distinguish one class of plants from another. Let it be re- membered, therefore, that Moiiocotyledonous Plants, or Monocotyledons, are those which have only one cotyledon or seed-leaf to their embryo. Dicotyledonous Plants, or Dicotyledons, are those which have a pair of cotyledons or seed-leaves to their embryo. Polycotyledonous Plants, or Poly cotyledons, are those which have more than one pair of cotyledons or seed-leaves to their embryo. Analysis of tlie Section. 24. Flowers produce Fruit; this, the Seed; of this the essential part is the Embr3'-o which grows. 25. It is
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