This section is from the book "British Wild Flowers - In Their Natural Haunts Vol5-6", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
The habitat of this plant is cultivated ground, fields, and waste places. The habit is erect. The plant has a heavy odour. The stem is stout and branched. The leaves are large, long-pointed, broadly ovate, heart-shaped, pale green, membranous, angular, toothed, the teeth large, distant, 2-4 on each side, 3-5 nerved at the base. The flowers are in loose, axillary, nearly leafless corymbs or spikes, in large clusters. The perianth does not cover the utricle. The seeds are coarsely minutely pitted, not keeled, opaque, large. The plant is 6 in. to 3 ft. high, flowering in August and September, and is a herbaceous annual.
The habitat of this plant is waste places near houses, towns, and villages. It may be a native on the beaches of Kent, Sussex, Dorset. The habit is erect or ascending. The plant is nearly devoid of hairs, rather strong smelling. The branches are prostrate. The leaves are ovate, rhomboidal, triangular, wedge-shaped below, where they are entire, acute, unequally sharply toothed above, bright green, shining, mealy when young. The leaf-stalk is not so long as the blade. The upper leaves are narrower, coarsely toothed. The flowers are in short, dense spikes, with spreading branches, the flowers cymose. The perianth-segments have a slight keel, and nearly cover the utricle, having a narrow membranous border. The seeds are acute, sharply keeled, minutely granular, dotted, opaque. The plant is 6 in. to 1 1/2 ft. high, flowering in August and September, and is a herbaceous annual.
The habitat of this plant is waste places. It may be native on muddy shores. The habit is erect or ascending. The plant is smooth, shining. The stem is leafy throughout, and has alternate bands of green, white or red. The leaves vary considerably. They are triangular, rhomboidal to ovate, entire, irregularly toothed, blunt or acute, wavy, or entire below, 3-nerved at the base. The flowers are in erect, dense, leafy, panicled, compound, terminal and axillary spikes. The flowers are frequently incomplete and crowded, the terminal flower 5-cleft. The calyx is 4 or 5 cleft. There are 1-2 stamens. The perianth-segments are not keeled and cover the utricle. The seeds are very small, vertical, smooth, shining, brown, obscurely keeled or blunt. The pericarp is very loose. The plant is 2 in. to 3 ft. high, flowering from April to October, and is a herbaceous annual.
The habitat of this plant is rich waste places. The habit is prostrate. The stems are usually spreading, widely-branched, shining, smooth. The leaves are green above, white, bluish-green, meal)' below, oblong, wavy toothed, blunt or round, wedge-shaped below. The flowers are in short, erect, simple, leafless, terminal and axillary, dense spikes. The perianth-segments are keeled and almost cover the utricle, leaving a narrow membranous border. The seeds have an acute keel, and are reddish, very small, the horizontal ones largest, the others vertical, netted, granular. The plant is 4-18 in. high, flowering from July to September, and is a herbaceous annual.
The habitat of this plant is waste places and cultivated ground.
The habit is erect or prostrate. The plant is dark-green, mealy. The lower leaves are opposite, spear-shaped (hence hastata), triangular, the lobes spreading, horizontal, acute, entire, and the upper leaves are lance-shaped, entire. The flowers are in simple or panicled spikes, interrupted, leafy below. The fruiting perianth-segments are triangular, rhomboidal, united below, prickly on the back, longer than the fruit. The seeds are large and small, the former dark-brown, rough, flattened, the smaller black, smooth, shining. The plant is 6 in. to 4 ft. high, flowering from July to September, and is a herbaceous annual.
The habitat of this plant is cultivated ground and waste places. The habit is more or less erect. The leaves are mainly opposite, triangular, spear-shaped, with spreading lobes, the upper ones also spear-shaped. The flowers are in dense spikes, panicled, the terminal short. The perianth-segments are blunt, scarcely exceeding the utricle, and are ovate to triangular, prickly on the back, united only below. The seeds are thick, black, polished, some dark-brown, larger, and with large perianths. The plant is 6-24 in. high, flowering from June to October, and is a herbaceous annual.