白喉乌头 bai hou wu tou

Rhizome unknown. Stem ca. 1 m tall, basally sparsely retrorse pubescent or nearly glabrous, apically spreading glandular pubescent. Basal leaf ca. 1, and proximal cauline leaves long petiolate; petiole 20--30 cm; leaf blade reniform or orbicular-reniform, ca. 14 × 18 cm, abaxially sparsely retrorse pubescent (hairs 0.5--0.8 mm), adaxially glabrous or nearly so, 3-parted; central lobe broadly rhombic, 3-fid; lateral lobes obliquely flabellate, unequally 3-fid. Inflorescence 20--45 cm, many flowered; rachis and pedicels densely spreading yellowish shortly glandular pubescent; basal bracts 3-fid, others linear, subequaling or longer than pedicels, to 3 cm. Pedicels 1--3 cm, with 2 bracteoles at middle or below; bracteoles narrowly linear or filiform, 3--8 mm. Sepals pale blue-purple, lower part white, abaxially pubescent; lower sepals ca. 1.1 cm; lateral sepals ca. 1.2 cm; upper sepal cylindric, 1.5--2.4 cm high, middle 4--5 mm in diam., beaked, lower margin 0.9--1.5 cm. Petals glabrous; lip linear, conspicuous; spur slightly circinate, longer than lip. Stamens glabrous; filaments entire. Carpels 3; ovary glabrous. Follicles 1--1.2 cm. Seeds obovate. Fl. Jul--Aug. 2n = 16.

Grassy mountain slopes, valleys, forests, forest margins; 900--2600 m. NW Gansu (Shandan Xian), N Hebei, Xinjiang [Kazakhstan, Kyrgyzstan, Mongolia, Russia (W Siberia)].