518 WILSON EXPEDITION TO CHINA 



This species is locally very common, forming dense dwarf thickets. The leaves 

 vary from obovate to lanceolate or lanceolate-ovate, from shining to dull green 

 above, and are densely or sparsely lepidote. 



Rhododendron ambiguum Hemsley in Bot. Mag. CXXXVII. t. 

 8400 (1911). — Schneider, III. Haridb. Lauhholzk. II. 1043, fig. 615 a-c 

 (1912). 



Western Szech'uan: south-east of Tachien-lu, on rocks in woods, 

 alt. 3000-3300 m., June and October 1908 (Nos. 1324, 1324% 1324''; 

 bush 1-2 m. tall, flowers yellow) ; Mupin, woodlands, alt. 2600-3000 

 m., June and October 1908 (No. 1324^=; bush 1-2 m. tall, flowers 

 yellow) ; south-east of Tachien-lu, woods, alt. 3000-3300 m., June and 

 October 1908 (Nos. 1330, 1330''; bush 1-2.5 m. tall, flowers yellow); 

 Tachien-lu, thickets, alt. 2600-3300 m., October 1910 (No. 4240; 

 bush 1-3 m. tall); Mt. Omei, thickets, alt. 2300-3000 m., October 1910 

 (No. 4252; bush 2.5-4 m. tall); Mupin, thickets, alt. 2300-2800 m., 

 October 1910 (No. 4265; bush 2-3 m. tall); without precise locahty, 

 alt. 2600-3300 m.. May 1904 (Veitch Exped. No. 3943); Mt. Omei, 

 June 1904 (Veitch Exped. No. 5144) ; near Tachien-lu, alt. 3000-4500 

 m., A. S. Pratt (No. 848). 



The undescribed fruit of this species is cylindrical, 1-1.5 cm. long, 4-5 mm. wide, 

 furrowed, often slightly curved, lepidote. 



This yellow flowered species is very abundant in thickets and rocky, exposed 

 places throughout the regions mentioned above. Apart from the color of the flowers 

 there is very little to distinguish it from R. yanthinum Bureau & Franchet, which 

 has, however, leaves usually more brownish below and slightly more slender fruits. 

 Hemsley & Wilson {Kew Bull. Misc. Inform. 1910, 115) refer Pratt's No. 848 

 to R. concinnum Hemsley, but the flowers are obviously yellow in color. 



Group b. 

 Leaves only lepidote. Flowers purple. 



Rhododendron yanthinum Bureau & Franchet in Jour, de Bot. V. 94 

 (1891). 



Rhododendron Benthamianum Hemsley in Kew Bull. Misc. Inform. 1907, 

 319; in Gard. Chron. ser. 3, XLVII. 4 (1910). — Hemsley & Wilson in Kew 

 Bull. Misc. Inform. 1910, 115. 



Rhododendron concinnum Hemsley & Wilson in Kew Bull. Misc. Inform. 1910, 

 115 (non Hemsley). 



Rhododendron atroviride Dunn in Jour. Linn. Soc. XXXIX. 484 (1911). 



Western Szech'uan: Mupin, alt. 2000-2300 m., June and Oc- 

 tober 1908 (No. 1 196; bush 1-2.5 m. tall, flowers purple); same lo- 

 cality, thickets, alt. 1600-2500 m. (No. 3447; bush 1-2 m. tall, flowers 



