7. Convolvulus arvensis Linnaeus, Sp. Pl. 1: 153. 1753.
田旋花 tian xuan hua
Convolvulus arvensis var. angustatus Ledebour; C. arvensis var. crassifolius Choisy; C. arvensis var. linearifolius Choisy; C. arvensis var. sagittatus Ledebour; C. arvensis var. sagittifolius Turczaninow; C. chinensis Ker Gawler; C. sagittifolius (Fischer) Liou & Ling.
Herbs perennial, with ± woody rhizomes. Stems prostrate or twining, to 1 m tall, glabrous or sparsely pubescent. Petiole 0.3-2 cm; leaf blade ovate-oblong to ovate, 1.5-5 X 1-4 cm, glabrous or pubescent, base hastate, sagittate, or cordate, apex obtuse, mucronulate; prominently 3-veined basally, upper parts pinnately veined. Inflorescences axillary, cymose, 1-3-flowered; peduncle 3-8 cm; bracts 2, linear, ca. 3 mm. Pedicel ca. 4 as long as calyx. Sepals unequal, 3.5-5 mm; outer 2 broadly oblong to obovate, shorter, abaxially sparsely pubescent or glabrous, margin ± ciliate, apex retuse; inner ones ovate-circular, margin membranous, apex obtuse or retuse. Corolla white or pink, broadly funnelform, 1.5-2.6 cm, midpetaline bands pubescent outside distally; limb shallowly 5-lobed. Stamens included, unequal; filaments minutely scaly basally. Disc cupular. Ovary ovoid, glabrous or sparsely pubescent. Stigmas cylindric. Capsule ovoid to subglobose, 5-8 mm, glabrous. Seeds 4 or fewer, dark brown or black, ovoid, 3-4 mm, tuberculate. Fl. Jun-Aug, fr. Jun-Sep. 2n = 24, 48, 50.
Cultivated areas, wasteland, roadsides, grassy slopes; 600-4500 m. Anhui, Gansu, Hebei, Heilongjiang, Henan, Hubei, Jiangsu, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Sichuan, Xinjiang, Xizang [Asia, Europe, North America, South America].