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formed parts. Their roots, when they have any, are usually intended to fix the plant to the rock or soil, rather than to draw nourishment from
it, as in the case of the large sea-weeds of our coast (Fig. 82), which are merely holdfasts to hind the plants firmly to the rock on which they grow. Mosses also take in their nourishment through their whole expanded surface, and therefore, chiefly by the leaves, but the stems also shoot forth; from time to time, delicate rootlets, composed of slender cells which grow in a downward direction, and doubtless perform their part in absorbing moisture. A moss is, therefore, like an ordinary herb in miniature, and exhibits the three general organs of vegetation—a root, a stem, and leaves.
But while the Mosses seem like ordinary herhs and trees in vegetation and external appearance, they are the same as the lowest kind of
composed of cellular tissues, strictly Bo called, and have no distinct vessels or ducts, and no true wood in their composition. The Mosses, along with the Algae, Fungi, &c., were, therefore, called Cellular Pl. De Candolle.*
5. All plants of a higher grade thia great authority distinguished by * name of VASCULARf Plants, because vascular and woody tissues entei into their composition when they are herbs, as well as when they form shrubs or trees.
The strength which woody tissue imparts enables vascular plants to attain a large sine, while mosses and other Cellular Plants are small, except when they live, like the sea-weeds, in water, which by supporting them, enables them to extend to any length. But although true mosses have no wood in their composition, yet the so-called Club mosses have. So also have the Ferns, the highest organised family of the lower grade of plants; and although these are mostly herbs, or plants with more or less woody stems creeping on or beneath the surface of the ground, yet in warm countries some species rise with woody trunks into tall and palm-like trees. But even these, like the humblest mosses, or the minutest moulds, spring from single cells or spores, and not from true seeds, and these spores are not produced by a flower.
Hence, plants of these lower grades are as a whole called Flowkrless or CRYPTOGAMoust plants, which, as has been already said, form one of the two great divisions of all plants—the other being the Flowering or Phanerogamous§ Plants, or those which bear true flowers, with stamens and pistils, and seeds in which is a living germ or plantlet.
2. THE FLOWERING PLANTS.
1. The growth of a flowering plant from the germ—that is, its germination—may be illustrated from any of the plants which blossom round us. Let us examine it as shown in the common garden bean, and in Indian Corn or Maize.
The cuts on the next two pages represent both at the commencement of germination, or sprouting.
2. In the " Fourth Eeader," p. 200, a description of the Embryo, or Germ, which is in all true seeds, is given. When you plant a bean the first sign of this germ waking into life is the appearance of a green point which shoots out and becomes the main root after a time. You see it in Figs. 85 and 86. It is the first offshoot from the embryo. A is a side view of the
* A great French botanist, born 1778, died 1841.
+ From Latin, vmculwa, a little vessel; hence, containing vessels, as veins, ducts, &c.
X From Greek, kryptos, concealed, gamos, marriage, meaning that their fructification is concealed.
5 From Greek, phancrot, open, and games, marriage.
bean, B is a side view of it with one of its seed leaves, or cotyledons * removed. These cotyledons are the food of the infant plant stored up for it, to supply its wants till it is able to draw nourishment from the air and earth for itself. In these two cuts r is the radicle, or root, p is the plumule, or bud which is the beginning of the stem, and will grow up between the cotyledons and at last break through the earth and develope into the growing stalk, with its leaves, &c.; a is only the point where one of the cotyledons has been cut off. You see how there was a germ in the bean from the first, which is only quickened and made to grow, by
Fig. 86. moisture, light, and heat. It is a true seed, bearing in it the embryo of a future plant, and supplying it with food while it is weak and tender.
3. A grain of Indian Corn shows the growth of a germ very strikingly. Here are five illustrations of it.
Let me explain the various parts of these. 1 is the dry grain of corn. You have often, no doubt, seen it. In 1 a this grain is cut through lengthwise; in 1 b it is cut across, so as to show the embryo within. * Greek, koiyledem, a cup.
In these sections p is the skin or rind; alb is a store of albumen on which, the young lant will live at first, c, a, r, col, are the embryo or germ
of this future plant—the living plantlet, ready, when the sun, the rain, and the soil enable it, to break out as a plant of Indian Corn. Of these letters