Questions.—What is said of one of the uses of leaves? What of the variety in their shapes? Mention some of these shapes. In what other things do leaves vary besides shape? What is said of the arrangement of leaves on their stems? What is said of their different sizes? What is said about observing the shapes of leaves?
CHAPTER XVIII.
MORE ABOUT LEAVES.
Beauty of common leaves.
Leaves are such common things that we do not think how beautiful they are. But take any common leaf into your hand and look at it. Take the leaf of the strawberry. See how prettily it is notched. Hold it up to the light and see the lines that run from the middle line to the edge. Then see the fine net-work between these lines. How delicate and beautiful! The leaf of the raspberry is even more beautiful than the strawberry leaf, if you pick it from a new shoot. See the fine points on its edge, and see how delicate are its lines and net-work as you hold it up to the light.
Ribs in leaves.
Observe the back of a leaf, and you will see ribs that spread out from the main rib in the middle to the edges. These are the frame of the leaf, just as timbers are the frame of a house. They are to the leaf what whalebones are to an umbrella. They give strength to it. Without them it would droop like a wilted leaf. It would not stand out straight and firm. The wind would blow it every way, like a rag tied to a stick.
You see these ribs very large in broad spreading leaves. They are large in grape-leaves, and in the leaves of the rhubarb-plant, or pie-plant, as it is often called.
In leaves that are very stiff and firm these ribs are so small, that at first you would say there were none. This is the case with the leaf of the pear and the orange. There is one strong rib running through in the middle of the leaf. But there are no strong ribs branching out from this. The leaf is so firm that it does not need them.
The upper and under side of leaves.
See the difference there is between the upper and the under side of a leaf. The upper is greener than the under side. In the grape-leaf the under side is covered with a very fine white fuzz. If you tear the leaf gently, you can see the delicate white fibres of this furze across the rent. In the silver-leaf poplar there is a silvery whiteness on the under side of the leaf. This makes the tree look very pretty as its branches are moved back and forth by the wind.
I have thus told you a few things about leaves. By looking at them yourselves you will see a great many things in them that will interest you. Look at them as you walk in the garden or roam in the field, and you will see that there is no end to the variety. And among them all you can not find one that is not beautiful when you examine it.
Leaves seen through the microscope.
Leaves are very beautiful if you look at them through a microscope. Take the most common leaf and look at it in this way, and you will be delighted. You will be surprised to find how much beauty there is in leaves that you knew nothing about before.
And now I will tell you about some leaves of a very singular character.
There are some leaves that are of very singular shape. I will mention only a few.
Leaf of the side-saddle flower.
Here is the leaf of the side-saddle flower, as it is called. It is shaped somewhat like a butter-boat. You see that it is open. It can hold considerable water. It has a kind of lip, which looks as if it were made in order that water might be poured out of it easily. This plant grows in some parts of this country. The flower is purple, and has a curious shape. It is on a stalk that stands up in the midst of about half-a-dozen of these leaves.
Chinese pitcher-plant.
One of the most singular leaves is that of the Chinese pitcher-plant. At the end of the leaf the main rib extends out like a tendril, and this ends in the appendage which is represented here. It is in the shape of a pitcher, and has, as you see, a regular lid. This is generally shut down, though, as you see it here, it is raised up. The rain can not, therefore, get in, and yet the pitcher is always full of water. It holds about a tumblerful. Now how do you think this water comes there? It is a part of the sap that comes to the leaf. The watery part of the sap is poured from thousands and thousands of little mouths on the inside of the pitcher; and so it is kept filled with water. This plant is quite common in the island of Ceylon. There it is called monkey-cup, because the monkeys sometimes open the lid and drink the water. And men sometimes drink from these leaves when there is no spring of water where they can quench their thirst.
Venus’s fly-trap.
The leaf of the Venus’s fly-trap, which grows in North Carolina, is a real trap for flies and other insects. Here you see the leaf as it is spread out, wide open. It looks as if there was no danger there. But let an insect alight on the leaf, and he is made a prisoner at once. The two parts of the leaf close together, as you see, and the points on the edges are locked together, so as to furnish bars to the prison. You see a little insect caught in this leaf that had lighted only on its very edge. He can not get away, and there, poor fellow! he must die a slow death. Of what use it is to have such traps for insects we do not understand.
Leaves of the fern.
This is the leaf of the common fern or brake. It is beautiful if you examine it, for it is very delicate. And it has one great peculiarity. The flowers of the plant are on the under side of the leaf. They are where you see the little round spots. If you look at the leaf with a microscope you can see the different parts of the flowers.
Thick leaves.
Most leaves are thin, but some are quite thick. This is the case with the leaves of the India-rubber tree. The wax-plant has thick leaves, which, with the flowers, look so waxy as to give the name to the plant. The flowers of the cactuses grow right out from the thick fleshy leaves, making these plants look very awkward, although the flowers are so beautiful. And it is a singular fact, that if one of the leaves is broken off and put into the ground it will take root and grow.
Live-forever.
Did you ever make a blow-bag, as it is called, of the leaf of the live-forever, as children very often do? If you have not, I will tell you how it is done. The leaf is rather thick, and is made of two layers. These you can separate at the stem-end of the leaf, and then by pinching the leaf and blowing into it you can make it puff out like a bag. You must do this very carefully, or you will break the layer on the under side of the leaf, which is very thin, while the upper layer is thick.
Ribbon-grass.
The leaf of the ribbon-grass, as it is called, is very singular in one respect. It is very prettily striped, but you can not find any two leaves that are striped exactly alike, any more than you can find two faces exactly alike among all the people on the earth.
Questions.—What is said of the beauty of common leaves? Tell about the ribs of leaves. What leaves have large ribs? How is it with the leaf of the pear and the orange? What is the difference between the upper and the under side of leaves? Tell about the grape-leaf. And about the leaf of the silver-poplar. What is said of the beauty of leaves as seen through the microscope? Tell