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 usually waste places. The habit is erect. The stem is branched, slender, finely furrowed, hollow. The root is spindle-shaped. The leaves are narrow, triangular, linear to oblong, bipinnate, the leaflets cut, linear, the pinnules opposite, the lobes narrow-pointed. The flowers are white, in irregular umbels, on slender stalks, with no partial involucre, and the general involucre may be reduced to 1 leaf, or absent. The carpels are aromatic, oblong, with short ridges. The styles are spreading. The plant is 1-2 ft. high, flowering in June and July, and is a herbaceous perennial.
The habitat of this plant is garden rubbish, cliffs, rocks and old walls, banks, roadsides, waste places. The plant is erect in habit, hairless, shining. The stems are much-branched, round, finely-furrowed, solid. The leaves are greenish, shining, triangular, tripinnate, with many, more or less stalkless leaflets, those of the lower leaves ovate to wedge-shaped, divided into three nearly to the base, toothed, those of the upper leaves ternate, lance-shaped, entire. The flowers are white or yellow, in regular, flat-topped umbels. The partial involucre is slender. The rays are numerous. There are 2-3 bracts, often divided, and many bracteoles. The fruit is ovoid, green. The slender styles are bent back. The plant is 9-18 in. high, flowering from June to August, and is a herbaceous perennial.
The habitat of this plant is waste places, waysides, roadsides, rubbish-heaps. The habit is erect. The stem is hairy above the nodes only. The leaves are tripinnate, the leaflets are ovate, pinnatifid. The flowers are in stalkless, lateral umbels, with a leaf opposite. The fruit is very narrow, linear, smooth, twice as long as the beak. The plant is 1 1/2 ft. high, flowering from May to Jul)', and is a herbaceous annual.
The habitat of this plant is waste places. The habit is erect. The stem is slender, leafy, hollow, round. The leaves are triangular, bipinnate, cut, the segments broad, round, wedge-shaped, ovate, scalloped, lobed, the upper leaves with more linear segments, fleshy, loose. The leaves are membranous. The flowers are white, small, very irregular, in an umbel, which is stalked, of 5-10 rays. The bracteoles are short, linear, acute. The carpels cohere. The styles are slender, wavy. The plant is 1-2 ft. high, flowering in June and July, and is a herbaceous perennial.