They are indigenous or native; and exotic or foreign. 443. The parts of fructification consist of the calyx, or cup, which is the outer green covering of a flower. The corolla are the delicate leaves or petals of the flower generally coloured, and are the parts which constitute the beauty of the flower. Thectary, or nectarium, is the part within the corolla which secretes the honey. 444. The calyx and corolla are fine expansions of the outer and inner bark or rhind of the plant; and their evident purpose is, to protect certain delicate extensions of the pith and wood, which grow within the corolla, and are called the pistil and the stamen, by the peculiar organization of which the seed is produced. 445. The pistil is provided at its head with a gummy matter, and the stamen with a fine dust called pollen; and when the dust falls on the head of the pistil, it is there absorbed and carried down the style of the pistil to the germen or seed-vessel in the centre of the flower; where the seed is, in consequence, produced within a pericarp, afterwards called fruit. 446. Fruits, which afford us so many luxuries, are in fact, nothing more than the covering, or the natural means for protecting the seed of plants, and called, by botanists, Pericarps. Some pericarps are pulpy, as those of apples, pears, nectarines, &c. some are hard, as nuts; and some scaly, as the cones of fir-trees. Your contemplation further yet pursue; 447. It must not then be forgotten, that the design of the beautiful flowers which cover the earth is to create the seeds of future trees, that the leaves, or corolla, of the flowers are merely protections of the delicate pistil, stamen, and germen; that in this last are produced the seeds; and that for their protection is provided the pericarp, which we call the fruit. Go, mark the matchless workings of the POWER In colour these, and those delight the smell; To dance on earth, and charm all human eyes.--COWPER. 448. Linnæus seized on the variations in the num ber of stamens as a means of classing the vegetable kingdom into twenty-four denominations. Those flowers having one pistil, and but one stamen, he called mon-andria; those of two stamens he called di-andria; three, triandria; so on up to twenty stamens, and above twenty polyandri. When he found stamens in one flower, and pistils in another, on the same plant, he called them diœcia, and on different plants polygamia. When altogether invisible, cryptogamia, 449. Nothing can be more easy than to remember the names of these 24 classes; they are, 1. Monandria, one stamen. 6. Hexandria, six stamens, all of equal length. 8. Octandria, eight stamens. 9. Enneandria, nine stamens. 10. Decandria, ten stamens, filaments separate. 11. Dodecandria, twelve stamens to nineteen inserted on the receptacle. 12. Icosandria, twenty or more stamens, inserted upon the calyx or corolla. 13. Polyandria, many stamens. 14. Didynamia, four stamens, two long, two short. 15. Tetradynamia, six stamens, four long, two short. 16. Monadelphia, filaments united at bottom, but separate at top. 17. Diadelphia, filaments united in two sets. sets. 19. Syngenesia, filaments united, and five stamens. 20. Gynandria, stamens inserted on the pistil, or on a pillar elevating the pistil. 21. Monacia, stamens and pistils in separate corollas, upon the same plant. 22. Diæcia, stamens and pistils in distinct corollas, upon different plants. 23. Polygami, various situations; stamens only, or pistils only. 24. Cryptogamia, stamens and pistils inconspicuous. Obs. I have introduced beneath, a representation of the pistils and stamens of a few of the first classes; and the pupil will, doubtless,be led to observe them within any flowers which fall in his way in his walks or otherwise. Y WAY 01 450. The Triandria contains chiefly the natural tribe of grasses; the hexandria, the lilies. The Icosandria contains the edible fruits; the polyandria, has many poisonous plants. The Tetradynamia contains the natural tribe of flowers, which are antiscorbutic. The Monadelphia is composed chiefly of the mallow tribe. Diadelphia consists of the pea tribe, which produces edible seeds. Syngenesia possesses the compound flowers. And the cryptogamia contains the natural tribes of ferns, mosses, sea-weeds, and mushrooms. Obs.-The first order of the fourteenth class, denominated "didynamia gymnospermia," are all innocent or wholesome: those of the other order, are fetid, narcotic, and dangerous; being allied to a large part of the pentandria monogynia, known to be poisonous, as containing henbane, night-shade, and tobacco. The whole class tetradynamia is wholesome. Whenever the stamens are found to grow out of the calyx, they indicate the pulpy fruits of such plants to be wholesome. The papilionaceous plants are wholesome, except the seeds of the laburnum; which, if eaten unripe, are violently emetic and dangerous. Milky plants are generally to be suspected. Umbelliferous plants, which grow in dry or elevated situations, are aromatic, safe, and often wholesome; while those that inhabit low and watery places, are among the most deadly poisons. 451. Other distinctions in each class produce a division of the classes, called Orders. A further division of the orders, founded on distinctions in the nectariam, led to the Genera. Other divisions of the genera, in regard to the root, trunk, leaves, &c. lead to Species; and casual differences in species are called Varieties. 452, The natural substances found in all vegetables are, sugar in sugar-cane, beet, carrots, &c. gum or mucilage, which oozes from many trees; jelly, procured from many fruits; turpentine and tar from the pine; bitters, from hops and quassia; and the narcotic principle from the milk of poppies, lettuce, &c. 453. The vegetables of the greatest value to man, are those which produce gluten or starch; as wheat, potatoes, barley, beans, &c. Oils are produced by pressing the seeds or kernels of vegetables; as olives, almonds, linseed, &c. Volatile oils are distilled from peppermint, lavender, &c. Wax is collected from all flowers by bees. 454. Resins exude like gum from firs and other trees; and are known as balsams, varnishes, turpentine, tar, pitch, &c. Of this class, too, is Indian rubber; which is a gum that exudes from a certain tree in South America. Iron also mixes with the substance of most vegetables; and is the cause of the beautiful colours of flowers. Potash is obtained from the ashes of burnt vegétables; as kelp, vine, fern, &c. Obs. The classes monocía and dioecia, which have the pistil and stamens in different flowers, and on different plants, have the pistil fructifed by the bees and other insects, which enter the corolla to extract the honey from the nectarium. The pollen in those flowers which have stamens only, falls on their bodies, and is carried by them to the flowers which have pistils only. And it deserves to be noticed, as a proof of the contrivance of the DIVINE ARCHITECT of Nature, that when the pistil is shorter than the stamens, the flowers grow upright, that the pollen may fall from the anthers of the stamens or the stigma of the pistils; but when the pistil is longer than the stamen, the flower hangs downward, that the pollen, in falling, may be caught by the stigma of the pistil. -Who can paint Like Nature? Can imagination boast, And can he mix them with that matchless skill, And lose them in each other as appears THOMSON. |