Rhizomes shortly creeping, thick. Leaves grayish green on both surfaces, linear, 25--55 cm × 5--8 mm, 3--5-veined, base surrounded by persistent fibers. Flowering stems 50--60 cm, hollow, 1- or 2-leaved; spathes 3, green, lanceolate, 6--9(--16) cm × 8--10 mm, 2-flowered, apex long acuminate. Flowers yellow, 6--10 cm in diam.; pedicel 3--11 cm. Perianth tube 0.5--1.2 cm; outer segments with purple-brown stripes and spots, obovate, 6--6.5 × ca. 1.5 cm, claw with conspicuous, dark purple auricles on both sides; inner segments slanting outward, oblanceolate, 4.5--5 cm × ca. 7 mm. Stamens ca. 3.5 cm. Ovary 1.2--1.8 cm. Style branches dark yellow, 4.5--6 cm. Capsule ellipsoid-cylindric, 3--4 × 1.5--2 cm, 6-ribbed, apex not beaked. Seeds brown, semiorbicular. Fl. May--Jun, fr. Jun--Aug. 2 n = 40*.

There continues to be a great deal of confusion among the “Sibiricae” irises of SW China, and a thorough revision is needed based on field and laboratory studies. Some of the difficulty arises because species nos. 2--5 were described from cultivated material. It seems to one of us (Noltie), from herbarium specimens, that no distinction can be made between the two yellow-flowered species, Iris wilsonii (the earlier described) and I. forrestii, and that I. bulleyana is merely a purple-flowered form of the same species. Iris chrysographes and I. delavayi are probably distinct, though very difficult to recognize in the herbarium. The distributions given in the present account should be treated with caution as they are largely based on herbarium material.

* Forest margins, hillsides, meadows, damp riversides; 2900--4300 m. Gansu, Hubei, Shaanxi, Sichuan, Yunnan.