1923] WILSON, THE RHODODENDRONS OF NORTHEASTERN ASIA 43 



Candolle, Prodr. vn. 727 (1839).— Maximowicz in Mem. Acad. Sci. St. 

 Petersb. ser. 7, xvi. no. 9, 18, t. 4, figs. 1-10 (Rhod. As. Or.) (1870).— 

 Franchet in Nouv. Arch. Mus. Paris, ser. 2, vi. 77 (PL David. I. 197) 

 (1883). — Hemsley in Jour. Linn. Soc. xxvi. 27 (1889). — Komarov in 

 Act. Hort. Petrop. xxv. 205 (Fl. Mandsh. in.) (1907).— Chipp in Bot. 



— Schneider, 111. Handb. Laubholzk. n. 475, 

 TTemslev & Wilson in Kew Bull. Misc. In- 



Mag. cxxxiv. t. 8198 (1908) 



figs. 315 p-q, S16g (1909).- 

 form. 1910, 117. — Pampanini in Nuov. Giorn. Bot. ItaL n. ser. xvn. 683 

 (1910) .— Rehder & Wilson in Sargent, PL Wilson. I. 513 (1913).— Bean, 

 Trees & Shrubs Brit. Isl. n. 368 (1914).— Rehder in Bailey, Stand. Cycl. 

 Hort. v. 2938 (1916).— Millais, Rlodod. 210 (1917).— Nakai, Fl. Sylv. 

 Kor. pt. vin. 30, t. 7 (1919).— Osborn in Garden, lxxxiv, 270, fig. (1920). 



Rhododendron Rosthornii Diels in Bot. Jahrb. xxix. 509 (1900). 

 Rhododendron Pritzelianum Diels 1. c. 510. 



A much-branched shrub, 1-2.5 m. tall, with branches rigid, twiggy, 

 lepidote and pubescent; bud-scales lepidote without, ciliolate, caducous. 

 Leaves persistent for one year, scattered, petioled, oblanceolate to lan- 

 ceolate, 1.5-4 cm. long, 0.5-1.5 cm. wide, acute or obtuse at apex, with a 

 gland-tipped mucro, narrowed at base to the petiole, dark green, finely 

 reticulate, with scattered lepidote glands above, densely covered with 

 pale- to rust-brown lepidote scales below. Flowers white, very numerous, 

 0.8-1 cm. across in terminal racemose clusters, rhachis pubescent, pedicels 

 ascending-spreading, slender, rigid, 1-2 cm. long, densely lepidote; calyx 

 persistent, shallow, saucer-shape, tube 0.5 mm. long with 5 lanceolate to 

 triangular teeth each 1-1.5 mm. long, lepidote, often ciliolate; corolla 

 rotate-campanulate, lepidote without, 5-lobcd, lobes spreading from about 

 the middle; stamens 10, exserted, filaments flattened at the base, glabrous; 

 pistil shorter than the stamens, ovary ovoid, lepidote, style glabrous, 

 stigma simple. Fruit oblong, lepidote, shining dark brown, 0.5-0.8 cm. 

 long, tipped with the persistent style; seeds fusiform, winged at the ends, 

 yellow-brown. 



Habitat. Mountains of northern Korea and westward through southern 

 Manchuria, the northern provinces of China to the borders of Thibet with 

 the southern limits of its range in the provinces of Hupeh and Szech'uan. 



This interesting Rhododendron was the first known Chinese species. 

 It has a greater range of distribution than any other Chinese Rhododendron 

 extending as it does from the mountains west of Peking to those of the 

 Chino-Tibetan borderland, and, growing in Mongolia and Korea. It 

 has the distinction also of being the only Chinese species hardy in the 

 Arnold Arboretum. As I know it in Hupeh and Szech'uan it grows on 

 cliffs and fully exposed places where it forms masses of irregular shape 



from 3 to 8 ft. through and tall. It is fairly common as a small bush on 

 the mountains behind Port Arthur in south Manchuria. In foliage and 

 flower it suggests a Ledum rather than a Rhododendron, and the leaves, 

 like those of other gland-dotted species, are fragrant. The species was 



