1924] WILSON, THE RHODODENDRONS OF HUPEH 87 



sometimes more than 5-celled; corolla 5, 7 or 9-lobed; flowers terminal, rarely 

 terminal and lateral I. Eurhododendron. 



Shrubs with persistent or deciduous, non-lepidote leaves; ovary glabrous or tomen- 

 tose, never setose or lepidote; corolla rotate, subrotate or funnelform-campanu- 

 late; stamens 5 or 10; flowers lateral, solitary or in fascicles of 2 or more. 



II. Azaleas! rum. 



Shrubs or small trees with deciduous, or persistent, strignse or villose, sometimes 

 glabrous but never lepidote leaves; corolla funnelform to rotate, rarely campanu- 

 late; stamens 5-10; ovary usually strigose, rarely glabrous, never lepidote; 

 flowers terminal III. Anthodendron. 



Subgen. I. EURHODODENDRON Endl. 

 Rhododendron subgen. Eurhododendron Endlicher, Gen. PL 759 



(1839), emended. 



Rhododendron sect. i. Ponticum G. Don, Gen. Syst. ill. 843 (1834), including 



sections II, in and iv. 

 Rhododendron sect. in. Eurhododendron De Candolle, Prodr. vn. 721 (1839), 



including sections i, n and iv. 



KEY TO THE SECTIONS 



Leaves persistent, glabrous or tomentose beneath, never lepidote; ovary glabrous, 

 glandular or tomentose, never scaly; stamens 10 to 20; flowers several from a 

 terminal bud . 1. Leiorhodium. 



Leaves persistent, more or less clothed with lepidote glands; corolla rotate, cam- 

 panulate or funnelform; stamens 10; ovary lepidote; flowers several from a 

 terminal bud, rarely from terminal and lateral clustered buds. . .2. Lepipherum. 



Sect. 1. Leiorhodium Rehd. 



Rhododendron sect. Leiorhodium Rehder in Bailey, Stand. CycL 

 Hort. v. 2937 (1916). 



Rhododendron sect. Eurhododendron Maximowicz in Mem. Acad. Sci. St 

 P6tersb. s6r. 7, xvi. no. 9, 14 (Rhod. As. Or.) (1870).— Not Endlicher. 



KEY TO THE SPECIES 



Corolla 5-lobed. 



Leaves green on both surfaces. 



Leaves glabrous, except midrib below. 



Calyx annular, glabrous 1. R. sutchuenense. 



Calyx saucer-shape, villose 2. R. maculiferum. 



Leaves densely clothed with rufous, floccose tomentum on the under surface. 



3. R. deter sile. 

 Leaves pale gray or dun-colored on under surface. 



Indumentum uniform, firm, crustaceous; calyx annular with 5 minute, erect 



teeth 4. R. hypoglaucum. 



Indumentum not uniform, floccose and crustaceous; calyx membranous 

 with 5 prominent reflexed lobes 5. R adenopodum. 



Corolla 7-lobed. 



Leaves glabrous; petiole purplish, glabrous. 



Calyx annular, obscurely toothed; pedicels glandular. 



Flowers umbellate 6. R. Fargesii. 



Flowers racemose .7. JR. Houlstonii. 



Calyx saucer-shape, membranous with undulate teeth; pedicels not glandu- 

 lar or very rarely so 8. R. discolor. 



Leaves hairy; petiole bearded, glandular 9. /?. auriculatum. 



