3. The Amphibious Yellow Cress (N. amphibium).—An erect plant, two or three feet high, with fibrous root and creeping runners, flowering from June to September, moderately common on the banks of muddy streams. Its leaves are narrow-oblong, three or four inches long, deeply toothed, or cut into narrow lobes; and the flowers are yellow, similar to those of the other species, and similarly arranged, but with petals twice as long as the sepals. The pods are broad, only about a sixth of an inch long, with a rather long style.
In the marshes of the South of England we may often see the Marsh Mallow (Malva officinalis or Althæa officinalis), of the order Malvaceæ, flowering during August and September. Its stem is hairy, with erect flowering branches two or three feet high; and the leaves are shortly stalked, thick, velvety, broadly ovate, and sometimes divided into three or five lobes. The flowers are shortly stalked in the axils of the upper leaves, or sometimes collected into a terminal raceme. Round each one is a whorl of several narrow bracts, shorter than the calyx, and united at their bases. The calyx is five-lobed; and the corolla consists of five broad, rose-coloured petals. This plant is shown on [Plate V], Fig. 4.
The Great Hairy Willow-Herb.
The Marsh St. John's-wort (Hypericum Elodes—order Hypericaceæ) is a somewhat shaggy little plant, common in the bogs of many parts of Britain, more especially in West England and Ireland. It varies from a few inches to a foot in length; with prostrate stems rooting at the base; and rounded, opposite leaves without stipules. Both stem and leaves are clothed with white, woolly hairs, the latter on both surfaces. The flowers, which bloom during July and August, are of a pale yellow colour, and form a few-flowered, terminal panicle. They have five small, oval sepals, fringed with little red-stalked glands; five petals, about three times as long as the sepals; and many stamens, united to more than half way up into three bundles. (See [Plate V], Fig. 6.)
The Blue Marsh Vetchling or Marsh Pea (Lathyrus palustris—order Leguminosæ) is occasionally to be met with in boggy places, flowering from June to August. It is a smooth plant, with a weak, winged stem, two or three feet long; and pinnate leaves consisting of from two to four pairs of narrow, sharp leaflets, and terminating in a branched tendril. At the base of each leafstalk are two narrow, half arrow-shaped stipules. The flowers are of a bluish purple colour, and are arranged in one-sided racemes, of from two to six flowers on long stalks. The pods are smooth and about an inch in length. This plant is represented on [Plate V], Fig. 5.
The Purple Loosestrife.
Some of the Willow-herbs (Onagraceæ) are very partial to wet and boggy places. A few species of other habitats are described in Chapters [X] and [XI], and these, together with the members that come within the range of the present chapter, are readily distinguished by their willow-like leaves and the very long inferior ovaries of their flowers. We shall here note three species—
1. The Great Hairy Willow-herb or Codlins and Cream (Epilobium hirsutum).—A large, erect, hairy plant, from three to six feet high, with numerous underground suckers, and a stout, round, branched stem. Its leaves are opposite, sessile, often clasping the stem, narrow, and finely toothed. The flowers are nearly an inch in diameter, of a deep rose colour, arranged in terminal, leafy racemes. They have four broad, notched, spreading petals; eight erect stamens; and a four-lobed stigma. The plant is common in wet places, and flowers during July and August.