37. Parnassia trinervis Drude, Linnaea. 39: 322. 1875.
三脉梅花草 san mai mei hua cao
Stems (1 or)2-4(-8), 7-20(-30) cm, with 1 leaf near base. Basal leaves 7-9; petiole brown-striate, 0.8-1.5(-4) cm; leaf blade oblong, oblong-lanceolate, or ovate-oblong, 0.8-1.5 cm × 5-12 mm, arcuate 3-5-veined with veins prominent abaxially, base subcordate, truncate, or attenuate, apex acute. Cauline leaf sessile, semiamplexicaul, similar to basal ones but smaller, sometimes with a few rusty brown, hairlike appendages at base. Flower ca. 1 cm in diam.; hypanthium turbinate. Sepals lanceolate or oblong-lanceolate, ca. 4 × 1.5 mm, 3-veined abaxially, margin entire, apex obtuse. Petals white, oblanceolate, ca. 7.8 × 2 mm, 3-veined, base cuneate into a claw ca. 1.5 mm, margin entire, apex rounded, entire. Anthers ellipsoid; filaments 1.5-2 mm; staminodes flat, ca. 2.5 mm, stalk ca. 1 × 0.7 mm, lamina ca. 1.3 mm wide, 3-lobed, lobes shortly clavate. Ovary semi-inferior, oblong; style ca. 0.5 mm; stigma 3-lobed. Capsule 3-valved. Seeds brown, glossy, oblong. Fl. Jul-Aug., fr. Sep.
* Moist places in valleys, marshy meadows, river beaches; 3100-4500 m. Gansu, Qinghai, Sichuan, Xizang.