BALFOUR—NEW SPECIES OF RHODODENDRON. 95 
E.N.W. Yunnan. Mountains west of Fengkow. Alt. 
14,000 ft. Lat. 27° 40’ N. Flowers clear pure yellow. 
G. Forrest. No. 12,697. June 1914. 
E.N.W. Yunnan. Mountains of the Chungtien plateau. 
Alt. 13,000 ft. Lat. 27° 30’ N. G. Forrest. No. 12,731. 
July rgr4. 
E.N.W. Yunnan. Kari Pass, Mekong-Yangtze divide. 
Alt. 13,000 ft. Lat. 27° 40’ N. In rhododendron and mixed 
thickets. Shrub of 9-16 ft. Flowers (yellow ?). G. Forrest. 
No. 12,969. Aug. 1914. 
The rhododendron phylum which is represented on the 
Mekong-Salween Divide by Rh. Wardii, W. W. Sm. finds ex- 
pression to the East on the Mekong- Yangtze divide, the Chungtien 
plateau, and in the N.E. of the Yangtze bend in the plant here 
described as Rh. croceum, which diverges so much—in some 
characters clearly in relation to the drier environment—that on 
the evidence it must be kept distinct from the western type. 
Mr. Forrest has specimens from several localities, and they all 
agree in the characters which differentiate Rh. croceum from 
Rh. Wardii, near one another though these plants are. We 
want more of the Mekong-Salween plant for completion of the 
differential diagnosis, but the following characters suffice for 
recognition of the two species :— 
Rh. Wardii has adult leaves typically nearly elliptic with 
rounded summit in middle of which lies the horny mucro ; 
croceum has always oblong leaves which slightly taper at the 
apex into the mucro and are not usually rounded. ; 
The inflorescence in Rh. Wardii is quite umbellate; in Rh. 
croceum racemosely umbellate with a rhachis of about 1.5 cm. 
ng. 
ox 
. 
The caudate outer bracts of Rh. crocewm are not visible on 
any of the buds of Rh. Wardit. 5 
Both the calyx lobes and the outside of the corolla in Rh. 
croceum are gland-dotted; in Rh. Ward the calyx is more 
sparingly glandular and the corolla is eglandular. — 
The ovary in Rh. Wardii has many almost sessile red glands 
covering it; in Rh. croceum the glands which form an even 
denser covering to the ovary have long stalks and they are 
turned upwards to the top of the ovary. ; 
The capsule in Rh. Wardii is shorter and thicker and is 
sprinkled with short glands ; in Rh. croceum the longer thinner 
Capsule is densely covered with long-stalked glands. 
Rh. croceum belongs to a type of rhododendron which is 
presented in several species throughout Western China and the 
adjoining countries and which also appears in the Himalaya. 
The general features of the series may be briefly stated thus :— 
: R 
