ORDER XLIX.—AMPELIDEÆ.—THE VINE TRIBE.
The natural order Ampelideæ contains several genera, but of these only the Vine and the five-leaved Ivy are common in British gardens. It seems almost ridiculous to talk of the flowers of the Vine, as the bunches, even when they first appear, seem to consist of only very small grapes, which gradually become large ones. The flowers, however, though small and insignificant, are perfect, and they have each a distinct and regularly formed calyx and corolla. The calyx of the common Grape (Vitis vinifera) is very small, and remains on till the fruit is ripe; there are five petals (a in fig. 133), which never expand, but remain fastened together at the tip, detaching themselves at the base, when
Fig. 133.—Flowers of the Vine. it is necessary that they should give room to the ripening stamens (b). The petals, which form a kind of extinguisher, when they are raised by the five stamens, fall off (c), and occasion the chaffy appearance observable in clusters of Vine-flowers. The ovary is, when young, in two cells, each containing two seeds; and it is crowned with a nearly flat, round stigma, without any style. When the fruit begins to swell, the ovary becomes filled with a pulp, which is solid, and not contained in bags like that of the Orange; and the dissepiment that divided the two cells gradually wastes away. Two, and sometimes three of the seeds also frequently disappear, so that four seeds are rarely found in the ripe grape. The seeds themselves are bony, and covered with a jelly-like matter; and when they are cut open, they are found to consist of a large quantity of hard albumen, with a very small embryo at the tip. The Vine is a climbing shrub, with lobed leaves, which are frequently deeply cut; the bunches in which the grapes are disposed are called branched or thyrsoid racemes (see 137), and the tendrils, by which the plant climbs, are supposed to be abortive peduncles, drawn out into these long, flexible, curling bodies, instead of producing bunches of grapes. The footstalks of the leaves are articulated, and will separate from the branch without tearing them. The different species of vines differ from each other chiefly in their leaves; but in the American grapes the calyx is sometimes entire, and sometimes the stamens and pistils are in different flowers.
The five-leaved Ivy, or Virginian Creeper (Ampelopsis hederacea), differs very little from the Vine in the botanical construction of its flowers. The calyx is, however, almost entire, and the five petals separate in the same way as those of other flowers; but in other respects they closely resemble those of the Vines. The berries are small, and not palatable, though they might be eaten with perfect safety. The leaves are palmate, and they are divided into three or five stalked leaflets. The stems are climbing and rooting; and the leaves take a beautiful deep red in autumn. The genus Cissus also belongs to this order.
ORDER L.—GERANIACEÆ.—THE GERANIUM TRIBE.
The order Geraniaceæ contains several genera of well-known plants, the most popular of which are Pelargonium, Erodium, and Geranium, signifying Stork’s-bill, Heron’s-bill, and Crane’s-bill, which differ very slightly from each other. The greenhouse Geraniums, which are all either natives of the Cape of Good Hope, or hybrids raised in Europe from the species originally imported, were, till lately, all included in the genus Pelargonium; but what were sections of that genus have, by some botanists, been now made separate genera. As probably, however, this rage for giving new and different names to divisions and subdivisions will not be generally adopted, I will not trouble my readers with any other distinctions than those between the three leading genera; and even these, I think they will allow, appear very trifling. The calyx of the Pelargonium is in five sepals, and two of them end in a kind of spur; which is, however, not very perceptible, as it runs down the peduncle or footstalk of the flower, and grows to it, so as to seem only a part accidentally enlarged. The corolla is in five petals, the upper two of which are generally larger, and differently marked to the others. Sometimes there are only four, and sometimes there are six petals; but these are exceptions to the general rule. The perfect stamens vary in number from four to seven; but there are always ten filaments, which are dilated, and grow together at the base; and I was quite delighted with the sparkling gem-like appearance of the membrane which they form when thus united, when I looked at it through my little microscope. In the plant now before me (a hybrid called the Duke of Sussex), the upper parts of some of the stamens have turned into little petals, retaining the white membrane-like part at the base, and thus curiously exemplifying the manner in which double flowers are formed, which is always by the metamorphosis of the stamens, or of the stamens and pistil, into petals. The pistil of the Pelargonium appears, when young, to consist of a five-celled ovary, with a long slender style, the tip of which is divided into five slender curved stigmas. The cells of the ovary are, however, five one-seeded carpels, each having a separate style; and though both the carpels and styles appear firmly grown together when young, yet, in fact, they only adhere to an elongation of the receptacle (see a in fig. 134), which is here called the central axis, and from which, when ripe, they part with elasticity, and curl up, as shown at b; the styles, or awns, as they are sometimes called, being hairy inside.