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.