5. Linum perenne Linnaeus, Sp. Pl. 1: 277. 1753.
宿根亚麻 su gen ya ma
Linum sibiricum Candolle.
Perennials 20-90 cm tall. Taproot sturdy. Stems erect or ascendant, branched from base, woody at base. Leaves alternate, linear to linear-lanceolate, 2-4 cm × 1-5 mm, 1(or 3)-veined from base, base attenuate, apex acute. Flowers numerous, in racemose cymes, ca. 2 cm in diam., heterostylous. Pedicel 1-2.5 cm, erect or slightly excurved. Sepals ovate, 3.5-5 mm, 5- or 7-veined, margin entire; outer 3 sepals with apex acute; inner 2 sepals with apex obtuse. Petals blue to bluish purple, obovate, 1-1.8 cm. Styles distinct; stigma capitate. Capsule subglobose, 3.5-8 mm in diam., septicidal. Seeds brown, elliptic, flattened, 3.5-4 × ca. 2 mm. Fl. Jun-Aug, fr. Jul-Sep. 2n = 18.
Dry mountain slopes, sparse thickets, grasslands, dry plains, sandy and gravelly floodplains; below 4100 m. Gansu, Hebei, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shanxi, Sichuan, Xinjiang, Xizang, Yunnan [Mongolia, Russia; W Asia, Europe].