Fig. 118.—The Carnation.
The Wild or Clove Carnation (Dianthus Caryophyllus), which may be considered the type of the order, has an erect stem, swollen at the joints, with connate leaves, (see a in fig. 118). The flower, when single, consists of five petals, each with a very long narrow claw (b), and a rather broad limb or blade (c) serrated at the edge. The calyx (f) is tubular, with five vandyked teeth, which are in fact the tips of five sepals, into which the tube of the calyx may be easily divided with a pin. The tubular form of the calyx is admirably contrived to support the long claws of the petals, and to keep them in their proper places; particularly when the flowers are double, as the weight of the petals in that case frequently bursts the tube of the calyx. Every one fond of pinks and carnations must have observed the miserable appearance of the flower when thus deprived of its natural support; and to prevent the premature destruction of prize-flowers by this misfortune, professed florists sometimes slip a curiously-cut piece of card-board over the bud, which remains on after the expansion of the flower, and prevents the petals from falling out of place. Some florists tie the calyx round with thread, instead of using a pasteboard ring, which answers the same purpose. At the base of the calyx are two, four, or six leafy appendages (g), resembling bracts, which are called the calycine scales. These imbricated scales are, however, only found in the genus Dianthus. There are ten stamens (d) unequal in height, but none of them longer than the ovary round which they are placed. The ovary and the stamens are concealed in the cup of the flower, but the former is furnished with two styles, terminating in two long stigmas (e), which project beyond the flower, and which, when magnified, appear delicately fringed.
The genus Dianthus includes the Carnation, the Pink (Dianthus plumarius), the Chinese Pink (D. sinensis), the Sweet William (D. barbatus), and many ornamental flowers. Of these the Sweet William has the claws of its petals bearded; the flowers are produced in bundles or fascicles; and the calycine scales are so numerous and awl-shaped, that they give a bristly appearance to the flowers. The different species of Soap-wort (Saponaria) differ from Dianthus, in having no calycine scales; and this is also the case with the berry-bearing Campion (Cucubalus baccifer), the fruit of which is a fleshy capsule or berry, which finally becomes black, and has a singular appearance in the centre of the cup-like calyx, which remains on till the fruit is ripe. The flower of this plant is white, and the petals have a two-cleft limb. All the numerous species of Catchfly (Silene) are also without calycine scales, and the petals are generally deeply two-cleft; but they are distinguished by having a crown of petal-like scales in the throat of the corolla. There are also three styles instead of two; and the capsules are three-celled at the base, ending in six teeth at the top. The species have frequently a glutinous frothy moisture on the stem, in which flies sometimes become entangled, and hence the English name of the genus. One species, the Bladder Campion (S. inflata), has been used as food, and its young shoots, when boiled and sent to table like Asparagus, are said to have the flavour of green peas. The different species of Lychnis and Agrostemma resemble Silene closely in every respect, except in the styles, which are five, instead of three; these two genera, Viscaria, and Githago, differ very slightly from each other; and several of the species are known by different names: thus Ragged Robin (Lychnis flos cuculi) is made by some botanists an Agrostemma; the Corn-cockle is sometimes called Githago segetum, and sometimes Agrostemma Githago; the common Rose Campion is called sometimes Lychnis, and sometimes Agrostemma; and the Rock Lychnis, or Red German Catchfly, sometimes Lychnis Viscaria, and sometimes Viscaria vulgaris.
ORDER XXVII.—LINACEÆ.—THE FLAX TRIBE.
The order Linaceæ is a very small one; and, indeed, it consists principally of the genus Linum. The Flax was formerly included in the Caryophyllaceæ, which it resembles in having five petals, five sepals, and five stamens; but it also resembles the Mallow in its capsules, and in its stamens growing together at the base; and the Cistus in its persistent calyx, and the disposition of its sepals. These links, which connect one order with another, and make them appear alike but not the same, form, I think, one of the most interesting parts of the Natural System. We are led on from one gradation to another, by scarcely perceptible shades of difference through the vegetable kingdom; and, indeed, through the whole system of creation: the beautiful harmony, and unity of design, visible throughout, bearing the strong impress of the Divinity whose power has made the whole.
The common Flax (Linum usitatissimum), though in its appearance only an insignificant weed, is a plant of great benefit to man. The fibres of the stem are used to make linen, and the seeds (linseed) are crushed for oil. The flowers are blue, and have five regularly-shaped petals, which are twisted in the bud; and a distinct calyx of five pointed sepals, two of which grow from a little below the others, as in the Gum Cistus; and, as in that plant, the calyx remains on till the seeds are ripe. There are five stamens, the filaments of which grow together slightly at the base, and there are five little points like filaments without anthers, rising between the stamens. The petals are connected with the ring formed by the united filaments, and sometimes the petals themselves grow slightly together at the base. The capsule consists of five two-celled carpels, grown together; each cell containing one seed, and each carpel terminating in a rather slender style, tipped with a ball-like stigma. When ripe, the capsule opens naturally, by dividing into ten valves, to discharge the seeds; which are flat and shining, with a large embryo. These seeds are called Linseed in the shops, from Linum, the botanical name of the plant; and, as is well known, they are not only used for various purposes, but oil is expressed from them. The stem of the common Flax, though it is only an annual, consists of woody fibre, like that of a tree in its young state; and it is this fibrous part that makes the yarn for thread, after it has been separated from the fleshy part, by steeping the stems for a long time in water. The perennial Flax (Linum perenne), which, as its name imports, lasts several years, differs in little else from the common kind, except that its sepals are obtuse, and its leaves are much smaller and narrower. Both these are natives of Britain. There are many other species, some of which have yellow flowers.