are found both opposite and alternate leaves, as in the composite or sunflower family; and a single wild sunflower plant itself has opposite leaves below and alternate leaves above. 11. Of our forest trees, there are very few species with opposite leaves. If you see that the branches and leaves of a tree do not stand one opposite another on the stem, you can at once be sure that it is not an ash, a maple, or a buckeye, because all these trees do have opposite leaves. On the other hand, there are many trees having alternate branches and leaves, such as the oak, chestnut, elm, hickory, walnut, butternut, tulip-tree, magnolia, sycamore, alder, beech, birch, poplar, willow, sassafras, mulberry, hackberry, sweet-gum, linden, locust, and others. 1. WHO that has seen the sensitive plant has not noticed with wonder the strange sensibility of its leaves? When roughly brushed by the hand the plant makes three movements, thus described by Professor Gray. First, the numerous leaflets close in pairs, bringing their upper faces together and also inclining forwards; then the four branches of the leafstalk, which were outspread like the rays of a fan, approach each other; at the same time the main leafstalk turns downward, bending at its joint with the stem. So the leaf (for it is all one compound leaf) closes and seemingly collapses at the touch. In a short time, if left to itself, it slowly recovers the former outspreading position. 2. This movement which we may thus call forth in the sensitive plant is repeated by the plant of itself during the night. Various other plants fold up their leaves during the night, and this habit was called by Linnæus the "sleep of plants." 3. It was in the bird's-foot trefoil that Lin LEAVES OF SENSITIVE-PLANT. I næus first noticed the difference between the position of the leaves during the day and during the night. Scarcely had he made this discovery when he came to the conclusion that this change would be found not to be confined to this single plant, but would be general in vegetable life. From that time Linnæus, every night, tore himself from sleep, and in the silence of nature studied the plants in his garden. 4. At each step he discovered a new fact, and very soon satisfied himself that the change in the position of leaves during the night was observable in a considerable 1 This figure represents a piece of stem with two (compound) leaves; the lower one expanded, as it is when untouched: the upper leaf shows the posi tion which is taken, by quick movements, when roughly brushed by the hand. number of vegetables, and that in the absence of light plants quite changed their aspect, so that it became very difficult to recognize them. He further states that it was the absence of light, and not nocturnal cold, which was the principal cause of the phenomenon, for plants in hothouses closed themselves during the night just like those which were exposed in the open air. 5. The illustrious Swedish botanist made many observations on the diversity of position taken by leaves during the night, and he even attempted a classification of those differences. The most general idea which he sought to establish was, that the positions differed according as the leaves were simple or compound. Linnæus thought that the object, in these circumstances, was to place the young shoots under shelter from nocturnal cold and from the effects of the air. It is among the composite leaves, in short, that the difference between the waking and sleeping is most clearly indicated. 6. This strange sleep of plants vaguely recalls to us the sleep of animals. In its sleep the leaf seems to approach the age of infancy. It folds itself up, nearly as it lay folded in the bud before it opened, when it slept the lethargic sleep of winter, sheltered under the robust and hardy scales, or shut up in its warm down. We may say that the plant seeks every night to resume the position which it occupied in its early days, just as the animal rolls itself up, lying as if it lay in its mother's bosom. 7. What is the cause of the sleep of plants? It occurs in all states of moisture, and the length of their sleep is not influenced by any change of temperature. A celebrated French botanist supposed that the absence of light was the direct cause of the phenomenon. To assure him self of this, he subjected plants whose leaves are disposed to sleep, to the action of artificial light, furnished by two lamps, which were, when united, equal to five-sixths of daylight. The results were varied. 8. "When I exposed," he says, "the sensitive plant to the light during the night, and to the shade during the day, I observed that at first the plants opened and closed their leaves without any fixed rule, but after a few days they seemed to submit to the new conditions, and opened their leaves in the night, which was day to them, and closed them in the morning, which was their night. When exposed to a continuous light, they had, as in their ordinary state, periods of sleeping and waking, but each of the periods was shorter than ordinary. On the other hand, when exposed to continuous darkness, they still presented the changes from sleeping to waking, but very irregularly." 9. Returning to the sensitive plant, we may observe that it has to a certain extent the power of accustoming itself to a touch or shock. A botanist, carrying a sensitive plant in a carriage, noticed that the plant closed its leaflets and all its leaves drooped as soon as the carriage began to roll over the pavement, but by degrees it seemed to recover from its fright, and became habituated, so to speak, to the movements, for its leaves resumed their erect position, and its leaflets their full expansion. The carriage was then stopped for a time, and when it resumed its motion the plant responded by dropping its leaves as before, but after a time they expanded again, and so continued during the remainder of the journey. FIGUIER. Adapted. 17. THE FLOWER. dis-pens'er, that which bestows. |re-pro-duc'tion, act of reproducing. sym'me-try, proportion of parts. ten'e-ment, dwelling-place. 1. WHY comes the flower upon the plant? That fruit may come. And why the fruit? That it may hold, protect, and cherish the seed. And why the seed? That the plant may have offspring-that other plants may grow up and be as near like itself as one living thing can well be like another. 2. The flower is the beginning of the seed, the first step toward reproduction, and the fruit is the flower completed. If it does throw aside its floral ornaments, if it sheds its petals or any other adorning or useful parts of its blooming period, it still retains the maturing seed and ends in the ripened fruit. 3. Look inside of almost any flower and you will see embosomed in its petals the thread-like organs called stamens with little yellow knobs at their ends. Shake them; if they are ripe, they will give up the fine dust or pollen, so light that the breeze will blow it away. 4. Some flowers have few stamens, some have many, and of the latter the apple and cherry blossoms afford examples. Most of the different grasses have three stamens to each of their little flowers. Here for example is a head of timothygrass with its long thick bunch of flowers crowded together at the top of the slender stem. Early in the summer about June you may see the little stamens peeping out all around, three of them together, and their little golden knobs dangling in the breeze. Some plants have only two stamens on |