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five parts, which are joined together into one long beak which ends in five points; the seeds are covered with a skin and are shaped like a kidney, having often a long tip which is rolled round like a corkscrew.

12. Here we have a definition of the genus geranium; but many geraniums will answer to this description, so he goes on to describe some more special characteristics. The sepals in this particular specimen, he says, are joined together in one piece; the stem of the plant is woody, the joints are fleshy, the leaves are slightly feathered at the edge. These last marks are peculiar to that kind of geranium which he calls geranium gibbosum, and here we have the specific name. Any geranium which has the woody stem, the joined sepals, the fleshy joints, and the featheryedged leaves, will be the species called by Linnæus gibbosum.

13. You will see that by this system it is always possible to find out easily to what part of the vegetable kingdom your plant belongs and what its name is; and if, after you have traced its genus, there is no species which exactly agrees with yours, you then know that you have discovered a new species which has not been described before.

14. The other useful point in Linnæus's system was the accurate and precise terms he invented for describing plants. Before his time naturalists used any words which suited them, and, as different people have often very different ideas as to what is meant by long or short, round or pointed, etc., the descriptions were often of very little. value. But Linnæus could not work out his system without using very clear terms and explaining beforehand what he meant by them; and as his system of names was soon followed in other countries, botanists in all parts of the

world were able to recognize at once what was meant by the description of any particular plant.

15. Since the death of Linnæus very great advances have been made in the study of plants, and his artificial system has been for the most part replaced by the natural system of later botanists. Nevertheless his glory can never fade. If they are the greatest philosophers who bring together the largest number of separate facts under a common law, then does Linnæus rank high in this illustrious company, for his mighty hand it was that first seized the infinitely varied forms of vegetable life, from tropic palm to arctic lichen, that seized them, and, binding them together by the band of a great generalization, gave to the world, in one colossal bouquet, all the children of Flora,

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1. COMMIT a seed to the earth; plant, for example, a Lima bean at the depth of two inches in moist vegetable soil. The seed will not be slow to germinate: first swelling, and then bursting its outer skin, a vegetable in miniature will, after a time, slowly reveal itself to the observer. In the mean time two very distinct parts make their appearance: one, yellowish in color, already throwing out slender fibrous shoots, sinks farther into the soil,this is the radicle, or root; the other, of a pale greenish color, takes the opposite direction, ascends to the surface, and rises above the ground, — this is the stem.

2. This root and stem are the essential organs of vegetation, without which, when we have excepted certain vegetables of an inferior order, plants adorned with leaves and flowers cannot exist. How vast the difference between the verdant top of a tree, which rises graceful and elegant into mid-air, not to speak of the flower it bears, and the coarse, tangled mass of its roots and rootlets, without harmony, without symmetry! These organs, so little favored in their appearance, have, however, very important functions in the order of vegetable action.

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3. The chief offices of the root are two: in the first place, it attaches the plant to the soil, holds it in its place,

and prevents it from being overwhelmed by the elements. In the second, it feeds the plant by absorbing from the earth the sap necessary to its growth. How is this done?

4. The root branches again and again as it grows, throwing out numerous smaller branches. These hollow, threadlike rootlets suck up from the soil the water and other things which are to go through the stem or trunk and the branches to all the leaves. Here it is made into the perfect sap, which being distributed causes the plant to grow, to blossom, and to bear fruit.

5. The manner in which roots succeed in overcoming obstacles has always been a subject of surprise to the observer. The roots of trees and shrubs, when cramped or hindered in their progress, have been observed to exhibit considerable mechanical force, throwing down walls or splitting rocks; and in other cases clinging together in bunches, or spreading out their fibers over a prodigious space, in order to follow the course of a rivulet with its friendly moisture.

6. A celebrated botanist of the last century relates that, wishing to preserve a field of rich soil from the roots of a row of elms which would soon have exhausted it, he had a ditch dug between the field and the trees in order to cut the roots off from it. But he saw with surprise that those roots which had not been severed in the operation had made their way down the slope so as to avoid meeting the light, had passed under the ditch, and were again spreading themselves over the field.

7. There are some roots which are developed along the stem itself. These supplementary organs come as helps to the roots properly so called, and replace them when by any cause they have been destroyed. In the primrose, for

example, both the principal and the secondary roots springing from it perish after some years of growth, but the supplementary roots springing from the lower part of the stalk prevent the plant from dying.

8. In the tropical forests of America and Asia, the vanilla, whose fruit is so sought after for its sweet aroma, twines its slender stem round the neighboring trees, forming an elegant, flexible, and aerial garland, at once a grateful and pleasing ornament in these vast solitudes. The underground roots of the vanilla would not be sufficient for the nutriment of the plant, and the rising of the nourishing sap would take place too slowly. But Nature has provided for this inconvenience by the air-roots which the plant throws out at intervals along its stem. Living in the warm and humid atmosphere of tropical forests, the stronger shoots soon reach the ground and root themselves in the soil. Others float freely in the atmosphere, inhaling the moisture and conveying it to the parent stem.

9. A grand tree-the banyan, or the pagoda fig-tree-adorns the landscape of India, and presents the most remarkable development of aerial roots. When the parent stem has attained the height of some fifty or sixty feet, it throws out side branches in every direction, and each branch in its turn throws out supplementary roots, which descend perpendicularly in long slender shoots till they reach the ground. When they have rooted themselves in the soil, they increase rapidly in diameter, and soon form around the parent stem thousands of columns, each throwing out new lateral branches and new roots.

"The bended twigs take root, and daughters grow
About the mother tree, a pillared shade.”

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