松潘乌头 song pan wu tou

Caudex oblong, ca. 3.5 cm. Stem twining, to 2.5 m, branched, glabrous or nearly so. Middle cauline leaves slightly long petiolate; petiole 2.5--6 cm; leaf blade pentagonal, 5.8--10 × 8--12 cm, herbaceous or papery, both surfaces sparsely pubescent, 3-sect; segments nearly sessile or distinctly stipitate; central segment obliquely rhombic; lateral segments obliquely flabellate, unequally 2-parted. Inflorescence 5--9-flowered; rachis and pedicels glabrous or sparsely retrorse or spreading pubescent; proximal bracts 3-fid, others linear. Pedicels 2--4 cm, with 2 bracteoles at middle or above; bracteoles linear-subulate, 3.5--4.5 mm. Sepals pale blue-purple, sometimes yellow-green or white, abaxially glabrous or sparsely pubescent; lower sepals 1.2--1.4 cm; lateral sepals 1.3--1.5 cm; upper sepal high galeate, 1.8--2.2 cm high, shortly beaked, middle 7--9 mm in diam., lower margin 1.4--1.5 cm, slightly concave. Petals glabrous or sparsely pubescent; lip 4--5 mm, slightly concave; spur incurved, 1--2 mm. Stamens glabrous or sparsely pubescent; filaments entire. Carpels (3--)5, glabrous or ovary sparsely appressed pubescent. Follicles 1--1.5 cm, glabrous or sparsely pubescent. Seeds ca. 3 mm. Fl. Aug--Sep. 2n = 16*.

* Forest margins, scrub; 1400--3000 m. S Gansu, Hunan, S Ningxia, E Qinghai, S Shaanxi, S Shanxi, N and NE Sichuan.