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CHAPTER I.-THE LEAF.

THE pupil will see from the picture what is to be done first, and how we are to proceed in commencing the study of plants. Having collected some specimens, let us begin with the leaf. On these printed leaves there is a language which children have already learned; there is also a language written by Nature on the leaves that grow: we will now learn to read that.

EXERCISE I.

The Parts of a Leaf.

THE beginner will gather some leaves, and find out the names of their parts by comparing them with the picture.

Petiole.

FIG. 1.

Blade.

Stipules.

BLADE. The flattened green part of the leaf.
PETIOLE.-The leaf-stalk.

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STIP'ULES. Small bodies at the base of the petiole, that look more or less like leaves.

NOTES FOR TEACHERS.-The exercises begin with leaves, because they are the simplest and the most common parts of plants, and because they present the greatest variety of forms, and are most easily procured. The aim of the first exercise is to teach the parts of a leaf and their names. It is likely that the first gathering of leaves will be done carelessly, and that,

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BLADE. The flattened upper part of the leaf. SHEATH.-A leaf-stalk surrounding the stem. LIG'ULE.-The scale-like stipule often seen between the sheath and the blade.

when compared with Fig. 1, the specimens will be found lacking in some of the parts there seen. This will make it necessary to repeat the exercise. At the second trial the leaves will be pulled with more care, and the pupil will seek for those having all the parts seen in the picture. Let him point out the parts in each of his specimens, and give them their names, repeating the process till he can do it without hesitation or mistake.

EXERCISE III.

Venation.

VENA'TION.-The lines seen upon the leaf-blade are called its venation.

Hold up a leaf between your eye and the light, and, if you see a net-work of irregular lines, it is a net-veined leaf; but, if you see no such net-work, as in Fig. 4, it is a parallel-veined leaf.

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LOOKING AND OBSERVING.-There are plenty of boys and girls who have always lived in a garden, and yet, if you asked them the difference between a potato-leaf and a bean-leaf, they could not tell you.. They have looked at potato-plants and bean-plants often enough, but they have never observed them.

When we observe a thing, we not only look at it, but, as we look, we think particularly about it. For instance, after these exercises, when you look at leaf, you will think, what parts has it? and, is it netveined or not? You will observe these particulars about it.

THE SCHEDULE.-That you may be sure to look at plants with care, and that your teacher may see what you think about them, little diagrams, called schedules, are used, in which you are to write down what you observe. They have questions written upon them, which you are to answer by studying the plants themselves.

FIG. 5.

Parts?

SCHEDULE FIRST, DESCRIBING FIG. 5.

Blade, Petiole, Stipules.

Venation? Net-veined.

NOTE.-It will be observed that the attention of the child is restricted to one additional point at each exercise. This will prevent the confusion of ideas which is liable to arise when several new features of plant-structure are presented to the mind at the same time.

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