ENUMERATION OF THE SPECIES 

 SECT. I. RHODORA G. DoN 1 



Rhododendron sect. Rhodora G. Don, Gen. Syst. III. 848 (1834). 

 Endlicher, Gen. 759 (1839). Dippel, Handb. Laubholzk. I. 417 

 (1889), as section of subgenus Azalea, excluding his Nos. 29 and 31. 

 Koehne, Deutsch. Dendr. 455 (1893), as section of subgenus Azalea, 

 excluding his No. 36. Zabel in Mitt. Deutsch. Dendr. Ges. XI. 26 

 (1902), in part. 



Rhodora Linnaeus, Spec. ed. 2, 561 (1762); Gen. ed. 6, 218 (1764). Will- 

 denow, Spec. I. pt. 2, 866 (1798). De Candolle, Prodr. VII. 719 (1839). 

 Gray, Man. 267 (1848); ed. 5, 309 (1867). Britton & Brown, III. Fl. II. 

 560 (1897). Britton, Man. 699 (1901). Small in N. Am. Fl. XXIX. 44 

 (1914). 



Hochenwartia Crantz, Inst. II. 468 (1766). 



Rhododendron sect. Azalea, ser. 2, [subser.J b, Maximowicz in M6m. Acad. 

 Sci. St. Petersb., se"r. 7, XVI. No. IX. 28 (1870). Bentham & Hooker, 

 Gen. PI. II. 601 (1876), as subser. 2, in part. Drude in Engler & Prantl, 

 Nat. Pflanzenfam. IV. 1, 37 (1889), as subgenus Azalea, 4. 



Biltia Small, Fl. S. E. U. S. 884 (1903); in N. Am. Fl. XXIX. 48 (1914). 



Deciduous upright shrubs without strigose pubescence, densely or loosely 

 branched, sometimes irregularly dichotomous, but not whorled; branchlets gla- 

 brous or pilose to hirsute, winter-buds of many imbricate scales, glabrous or pu- 

 berulous. Leaves scattered or crowded at the end of the branchlets. Flowers 

 from a terminal bud, the leafy shoots from separate lateral buds; corolla two- 

 Lipped, or rotate-campanulate, rarely campanulate; stamens 10, or in one species 

 7 or occasionally 5 or 6, not or jonly little longer than the corolla, usually declinate; 

 ovary pubescent or glabrous and stipitate-glandular. Capsule usually with rather 

 thin valves. 



The type species of this section is R. canadense Torr. The section contains five 

 species, of which two are native of eastern North America and three are Japanese. 

 All these species are very distinct from each other and may be divided into three 

 groups. The first group, containing only R. canadense, is characterized by the 

 deeply two-lipped corolla, the lower lip divided nearly to the base, the glandular- 

 pubescent and sparingly setose ovary, the puberulous branchlets and the to- 

 mentulose under side of the usually oblong leaves and the glandular-puberulous 

 narrowly oblong capsule. The second group with three species, of which R. Vaseyi 

 is one, has a rotate-campanulate slightly two-lipped corolla, a stipitate-glandular 

 but otherwise glabrous or sometimes quite glabrous ovary, an ovoid to oblong 

 glandular-hirsute or stipitate-glandular or glabrous capsule, and glabrous or pilose 

 leaves and branchlets. The third group, consisting only of R. nipponicum, has a 

 campanulate nearly regular corolla, with the lobes shorter than the tube, a glandu- 



1 See page 91 for the Old World species of this section. 

 119 



