19. Asarum forbesii Maximowicz, Bull. Acad. Imp. Sci. Saint-Pétersbourg. 31: 92. 1887.
杜衡 du heng
Herbs. Rhizomes vertical, 1-2 mm in diam., internodes 0.5-1 cm. Leaves solitary; petiole 3-15 cm, glabrous; leaf blade adaxially dark green with white blotches along midvein, broadly cordate to reniform-cordate, 3-8 × 3-8 cm, abaxial surface glabrous, adaxial surface with short hairs along midvein, base cordate, lateral lobes 1-3 × 1.5-3.5 cm, apex obtuse to rounded; cataphylls reniform-cordate or obovate, ca. 1 × 1 cm. Peduncle ascending, 1-2 cm. Calyx dark purple, cylindric to campanulate, 1.5-2.5 × ca. 1 cm; sepals connate beyond attachment to ovary, abaxially glabrous; tube subcylindric, 1-1.5 × 0.8-1 cm, not constricted at throat, adaxially tessellate, orifice ring less than 1 mm wide; lobes broadly ovate, 0.5-0.7 × 0.5-0.7 cm, base smooth. Stamens 12; filaments much shorter than anthers; connectives slightly extended beyond anthers, rounded. Ovary half-inferior. Styles free, apex 2-lobed; stigmas lateral. Fl. Apr-May.
* Forests, moist shady valleys; below 800 m. Anhui, Henan, Hubei, Jiangsu, Jiangxi, Sichuan, Zhejiang.
This species is used medicinally, known as 土细辛 (tu xi xin).