矽镁马先蒿 xi mei ma xian hao

Herbs annual, to 30 cm tall. Roots slender. Stems with 4 lines of hairs. Proximal leaves opposite, distal ones in whorls of 3; petiole to 1.5 cm; leaf blade oblong, 1.5--2.5 X ca. 1 cm; segments 5--7 pairs, ovate to oblong-ovate, dentate, both surfaces densely lanulose. Inflorescences interrupted basally, long pubescent; bracts leaflike basally, rhomboidal apically. Calyx short cylindric, densely villous along veins; posterior lobe triangular, entire, lateral lobes larger, ovate, serrate. Corolla rose; tube shorter than calyx tube and galea; galea slightly falcate; lower lip shorter than galea, ciliate, middle lobe rounded, smaller than lateral pair. Filaments glabrous. Fl. Aug, fr. Sep.

* Alpine meadows, forests; 3500--4000 m. E and W Gansu, N Sichuan, E Xizang.