The Foxglove is generally taken as the type of this order, and it has a tubular corolla (see a in fig. 140) with a short limb (b), and a spreading calyx (c). There are four stamens of unequal length inserted on the base of the corolla
Fig. 140.—Foxglove (Digitalis).and hidden in its tube; and an oblong ovary (d), with a long style, and a two-lobed stigma (e). The fruit is a dry capsule with two cells, and numerous seeds. The flowers of the other genera are very irregular. In the Snapdragon, the corolla is what is called personate; and in the Calceolaria the lower lip is curiously inflated. The stamens also differ. In most of the genera there are four, but in Pentstemon there is a fifth, long and slender, and hairy at the point, but without any anther; and in Calceolaria and Veronica there are only two. Among the genera included in this order may be mentioned Buddlea, the flowers of which grow in ball-like heads; Paulownia, Maurandya, Mimulus, Alonsoa, and Collinsia. The Toadflax (Linaria), and several other British plants belong to it; but the Yellow Rattle (Rhinanthus), and some other allied plants, have been formed into a new order called Rhinanthaceæ; Chelone and Pentstemon have been formed into an order called Chelonaceæ; and Sibthorpia, Disandra, &c., into one called Sibthorpiaceæ. Trevirana or Achimenes, and Columnea, are removed to Gesneriaceæ.
The new order Cyrtandraceæ, including Æschynanthus, Streptocarpus or Didymocarpus, Fieldia, and Amphicoma, is introduced here: the first and last of these genera are new, and the others were formerly included in Bignoniaceæ.
ORDER CXLII.—LABIATÆ.
| Fig. 141.—A Labiate Flower. | Fig. 142.—Black Horehound (Ballota nigra). |
The plants belonging to this order include Mint, Sage, Thyme, and other kitchen aromatic plants, and several well-known British weeds. They are all distinguished by a tubular, bilabiate corolla with a projecting under lip (see a in fig. 141). In some plants the corolla is ringent, as shown in fig. 142, taken from Dr. Lindley’s Ladies’ Botany, in which a is the galea or helmet, and b the lower lip, which is three-lobed. There are four stamens, two of which are longer than the others, and the cells of the anthers differ from those of most other plants in spreading widely apart from each other, each being joined to the filament only at the tip. The pistil consists of four distinct carpels (c), a very long style lobed at the tip, and furnished with a very small stigma at the tip of each lobe (d). The flowers of some of the plants belonging to this order are disposed in a whorl round the stem; as, for example, those of the Dead Nettle (Lamium). Among the other plants belonging to the order may be mentioned the Bugle (Ajuga), and the Ground Ivy (Glechoma), both common but very pretty British weeds.