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6. Thus, regarding Neptune as the most distant of the planets, we find that Uranus, the next in order, revolves around the sun, to speak in round numbers, in one half of the time of Neptune; Saturn in one third of the time of Uranus; Jupiter in two fifths of the time of Saturn; the Asteroids, which supply the place of a missing planet, in three eighths of the time of Jupiter; and so on down to Mercury, the planet nearest the sun, whose time of revolution is not far from thirteen thirty-fourths of that of Venus, its nearest neighbor.
7. These numbers singularly correspond with those which denote the relative distances of the leaves of different species of trees, shrubs, and herbs, in their spiral revolutions around the central axis10 of their orbits.11 When we find the measures used in scanning "the plants, the poetry of earth," and "the stars, the poetry of heaven," to be the same, shall we doubt that one designer planned the whole ?*
JAX'-IL, the angle, on the upper side, form- 7 DI-VERS'-I-TY, variety. ed by a branch with a stem or leaf.
2 RE-GAL, kingly; royal.
3 PEST, plague; any thing very troublesome. 4 SPI-RAL, a line that winds like a screw.
5 BA'-SES, plural of ba'-sis, lower ends; that on which they rest.
8 MIS-CEL-LA'-NE-OUS, irregular; without rule.
10 AX-18, plural ax'-es, the central part of a stem; that around which any thing revolyes.
6 PRO-TU-BER-AN-CES, the little knobs or 11 ORB'-IT, the path or track of a revolving
* EXPLANATORY NOTE.-The following fractions show the distances around the stem from one leaf to another, in different species of plants:
In the third fraction in the series, 2 revolutions give 5 leaves; in the fourth, 3 revolutions give 8 leaves, and so on. It will be seen that the sum of any two consecutive numerators gives the next numerator. The same is also true of the denominators.
value of each fraction after the second is between
In the adjoining table the time of revolution of the planets is given in approximate or round numbers, and also the fraction or ratio of the time of one planet to the time of the one exterior to it.
It will be seen that these fractions, which nearly represent the ratio of planetary periodical revolutions, are the same as those which represent the law of Phyllotaxis, or Leaf Arrangement. The break in the series at the Earth, where the I ratio eight twenty-one is that of the year of Venus to the year of Mars, will be best explained in a =subsequent article on Astronomy.
"GOD might have made the earth bring forth
Enough for one and all,
The oak-tree and the cedar-tree
Without a flower at all.
"He surely might have made enough
For luxury, medicine, and toil
And yet have made no flowers."
3. These verses by Mrs. Howitt are very pretty, and, in a certain sense, very true; but, while it is admitted that God might have made and propagated' the oak-tree and the cedar-tree without flowers, it is manifest2 that he has not chosen to do so.
4. We read that, by Divine command, "the earth brought forth grass, and herb yielding seed after his kind, and the tree yielding fruit, whose seed was in itself, after his kind." The organs3 especially designed to secure the multiplication or propagation of plants are the flower, fruit, and seed; and they depend on each other in the order in which they are named.
5. It is true that plants are often multiplied by separation of shoots or buds, which, being complete in themselves, constitute an individual plant. Many leaves, as those of the orange and fig, may be separated from their stems, and, if carefully placed in the earth by their petiole or leaf-stalk, will take root and produce new plants. Dahlias,5 potatoes, and tulips are propagated from tubers or bulbs; roses, vines, etc., by cuttings or slips placed in earth; and appies, pears, and quinces by grafting or budding. This is, however, rather vegetable continuation and multiplication than reproduction.6
6. The flower, which Pliny fancifully called "the joy of the trees," is a peculiar kind of branch, consisting of a peculiar kind of leaves; and, whatever the laws are of the arrangement of branches with respect to each other, the same will regulate the arrangement of flowers. A leaf-bud, starting in all respects apparently like its fellows, becomes changed by some cause of which we are ignorant, although supposed to be by an increased supply of nutriment," and thus what would otherwise have been a branch or a leaf becomes a flower, perhaps of exceeding beauty in coloring, fragrant in odors, and producing a fruit luscious to the taste. Similar and equally important changes, which will be hereafter noticed, take place in other departments of Natural History.
7. A complete flower consists of four parts, or series of organs, viz., calyx, corolla, stamens, and pistil. (See Fig. 15.) The two former are rather ornamental than essential, as a flower, botanically speaking, can consist of stamens and pistil alone. Stāmens and pistils are the essential1o organs of a flower; but sometimes there is only one of these present, the other organ being in another blossom on the same plant, as in the Indian corn, where the ear is but half a flower, having for pistils what we commonly call the silk, while the tassel is the other half, containing the stamens.
8. This mode of flowering is seen in many forest trees, as the oak, beach, chestnut, birch, and walnut. Frequently, also, one half of the flower, or the blossom with one essential organ, is on one plant, and the other organ on another plant.
The several Parts of a complete Flower.
Fig. 15 shows the different parts of the flower of the Evening Primrose, Enothera fruticosa.
Pe, Pe, in the drawing on the left, are the petals of the flower, within which are the stamens surrounding the St pistil. The calyx, which is at the base of the flower, has been removed, but its four sepals may be seen turned down at s, on the stem at the right. Here the petals have been removed, the better to show the stamens, st, and the pistil, Pi. The top of the pistil of this flower is divided into four narrow stigmas; but in many plants it is a mere roundish knob. The letters a a show the anthers, or knobs on the top of the stamens. At o is the ō'-va-ry, which contains the seed. In many plants the ovary is at the lower end of the pistil, within the petals. At ov is shown the ovary, in a more advanced state, cut across. At Pol are showr grains of pollen from the anthers, highly magnified.
This is the case with the hop, hemp, willow, prickly-ash, and red cedar.
9. The calyx, which forms the outermost part of a complete flower, consists of one or more leaves, called sepals. Sepals are generally of a green color, and are arranged around the lower part of the flower. The term calyx, or cup, itself indicates its position to any one who can recall to mind the appearance of a rose-bud.
10. The corolla, which is in common language called the flower, consists of one or more leaves, termed pětals. Pětals are really leaves; but they differ from leaves constituting foliage much more than sepals. They are seldom green, but present the most brilliant colors, and perform but to a very limited extent, if at all, the breathing processes described under the head of leaves.
11. Corollas are mon-o-pet'-al-ous or pol-y-pet'-al-ous-that is, they have one pětal or more than one, according as they consist of one or more leaves. Beyond this distinction flowers are variously shaped, presenting to the eye a diversity as interesting in form as in color. Among the mon-o-pet'-al-ous, or one-leaved corollas, we find those that spread out the divisions of their petal in the form of a salver, others that diverge like the spokes of a wheel; some that, like the morning-glory, are shaped like a tunnel; some that are bell-formed; and others that, like the sage and snapdragon, are call ed labiate, or lip flowers, from their resemblance to the lips and mouth of animals.
12. The pol-y-pet'-al-ous, or many-leaved corollas, exhibit a still greater variety of forms. Among these may be mentioned those which, like the pea-blossom, are said to be butterfly-shaped, because they resemble the wings of a butterfly; those which resemble the lily, the rose, or the pink; those which are bell-formed, and salver-shaped, and wheel-shaped; and those which, as the cabbage, mustard, turnip, and wallflowers, are called cross-shaped, because their four petals are in the form of a cross. The seeds of all plants which have cross-shaped corollas are arranged in a kind of pod; and they are distinguished from other seeds by containing sulphur, the chemical effect of which is seen when a silver spoon is used
with mustard. The names of the principal forms of flowers are given in the explanation below.
13. But, besides those which have been mentioned, there are many very irregular flowers, such as the violet, columbine, 12 and nasturtion. Formerly the term nectary was applied to petals of unusual shape, especially when the flowers. were much frequented by bees; but this term is not now used by botanists as applicable to any distinct organ or part. Sometimes the general term perianth13 is given to the leaves of a flower when they are not readily distinguished as sepals or pětals.
14. We know not the causes which dispose11 the parts of some buds to become sepals, petals, etc., while others become leaves; but a flower is always prepared in the centre of a bud, or embosomed among its leaves a long time before they expand. In general a flower is formed rapidly, a few months at most being sufficient to pass it through all its stages of growth. In certain palms, however, some years appear to be required; and it is said that the rudiments15 of a flower may be discovered in the bud of a palm as many as seven years, in some instances, before the perfect flower expands.16
15. While annuals17 flower in a few weeks after their seeds are sown, biennials 18 demand some months, perennials 19 a longer time, and trees several years. Some, again, blossom in the winter, as the Christmas rose and the fragrant geranium; others in the earliest spring, as the snowdrop and the crocus; while others can not be made, by any known artificial means, to advance their time of flowering even a few weeks.
16. A great difference is also observable in the hours at
1. The flower called Phlox is salver-shaped; the botanical term for which is hy-pocra-ter'-i-form. 2. Woody Nightshade; wheel-shaped, or ro'-tate. 3. Tobacco; funnel-shaped, or in-fun-dib'-u-li-form. 4. Canterbury Bell; bell-shaped, or cam-pan-u late. 5. Mustard; cross-shaped, or cru'-ci-form. 6. Pink; pink-shaped, or car-y-ophyl-la-ceous. 7. Lily; lily-like, or lil-i-a'-ceous. 8. Catnip, Sage, etc.; lip-shaped or la'-bi-ate. 9. Pea, Bean, etc.; butterfly-shaped, or pa-pil-io-na'-ceous.