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c is the cotyledon, a is the plumule, or little feather which is to grow into the stem, &o. r is the young root, col is the root-sheath, through which the root will burst. Figures 2, 3, 4, 5 and 6, give the successive stages of germination. 3 a and 3 b are side and front views of the plant at the same stage. In all, p is the plumule; and r the radicle, or root. a a are irregular, or adventitious roots—as distinguished from the true root, b is the first leaf produced; the star, x, is the first leaf which opens apart from the Btem. S in No. 2 is the storehouse of albuminous food from which the germ draws its supply at first.
THE FORMATION OF FRUITS.
1. The Flower has been already described in the " Fourth Reader," p. 197; of the Fruit of plants there are many varieties.
1. A Simple Fruit is a seed vessel formed by the ripening of one pistil, with whatever may have grown fast to it in the flower. Simple fruits are most conveniently classed as Fleshy, Stone, or Dry Fruits.
2. The principal sorts of fleshy fruits are the Berry, the Gourd, and the Apple forms.
3. A Berry is fleshy or pulpy throughout. Grapes, tomatoes, goose
Fig. 92. Section of an Orange.
berries, currants, and cranberries are good examples. Oranges and lemons are only berries with a thicker and leathery rind.
The Gourd fruit is, in the same way, only a sort of berry with a harder rind. The squasb, the melon, cucumbers aud the bottle-gourd, are examples of it. A Pome, or Apple Fruit, is the well-known fruit of the Apple, Pear,
Fig. 94. Quince and Hawthorn. It is formed from a flower in which a number of pistils (Fig. 93) growing in one are united with the Calyx or cup of the flower, and this calyx, growing very thick and fleshy, makes the whole eatable part, or flesh, of the fruit. The real seed-vessels in the quince, apple, and the like, consist of the five thin parchment-like cells of the core, containing the seeds. But in the pear and apple the flesh of the core, namely all inside the circle of greenish dots seen on cutting the fruit across, belongs to the Receptacle* of the flower which here rises so as
to surround the real seed-vessels. Cutting the apple lengthwise these dots appear as slender greenish lines, separating what belongs to the core from what belongs to the calyx. They are the vessels which in tha blossom belong to the petals and to the stamens above.
• Tip of the flower stalk from which the parts of a flower spring.
We give an illustration of the parts of a flower to recall them to mind (Fig. 96). It is the hindweed. c, calyx, cor, corolla, d, disk, a cupshaped elevation in this case, surrounding the hase of the ovary, o. s, style, st, stigma. Fig. 97 shows how the different parts of a flower often grow together. It is a fuchsia, pp, pistil, d, disk, a, a, stamens. cor, corolla, c, calyx, ped, peduncle.
4. In the Haw the cells become thick and stony, and so form a kind of Stone Fruit, or Drupe (Fig. 98). Plums, cherries and peaches are
familiar examples of stone-fruit. The stone does not belong to the seed but to the fruit. It has the seed in it, with coats of its own.
5. Dry Fruits are those that ripen without flesh or pulp. They are of
Fig. 101. A grain of Indian Corn. Fig. 102. Fruit of the Maple.
two classes—the one bursting open and scattering their seeds, the other
keeping them till the seeds grow, or the seed-vessel decays.
Of the First Class, which do not burst open, the Nut is an example. Beechnuts, chestnuts and acorns (Fig. 99), are familiar examples. The Achene fruits, or the dry one-seeded, closed, small fruits, which are generally mistaken for naked seeds, are a second kind of this class of dry fruits (Fig. 100). The Grain is a third variety. Indian corn, wheat, &c., are examples. In the Achene the seed is found whole within; but, in the Grain, when the outer coating is cut, the covering of the grain adheres to the seed-vessel within (Fig. 101). Key fruits are such as those of the ash, elm, maple, &c. These form the fourth variety. (Fig. 102.)