THE SUBGENUS ANTHODENDRON ENDL. 



Rhododendron subgen. Anthodendron Endlicher, Gen. 759 (1839), 

 emended. 



Azalea Linnaeus, Spec. 150 (1753), as to species 1-4. Desvaux in Jour. 

 Bot. Appl. I. 35 (1813). Roemer & Schultes, Syst. IV. 374 (1819), ex- 

 cluding species 12 and 13. Gray, Man. 268 (1848). K. Koch, Dendr. 

 II. 1, 171 (1872). Render in Bailey, Cycl. Am. Hort. I. 119 (1900), ex- 

 cluding A. albiflora, semibarbata, kamschatica. Britton & Brown, III. Fl. 

 11.558 (1897). Britton, M an. 698 (1901). Small in N. Am. Fl. XXIX. 

 41 (1914). 



Anthodendron Reichenbach in Moessler, Handb. Gew&chsk. I. 244, 308 (1827); 

 FL Germ. Exc. 416 (1831). 



Rhododendron sect. Pentanthera G. Don, Gen. Syst. III. 846 (1834). See 

 also page 124. 



Rhododendron a. Anthodendron, Endlicher, Gen. 759 (1839). 



Rhododendron subgen. Azalea Planchon in Rev. Hort. 1854, 43; with Tsusia as 

 distinct subgenus. Maximowicz in Bull. Acad. Sci. St. PStersbourg, XV. 

 229 (1870); in Mem. Acad. Sci. St. Pttersbourg, s<r. 7, XVI. 9, 24 (1870), 

 as section, with Tsusia as distinct section. Bentham & Hooker, Gen. 

 II. 601 (1876), as series, with Tsusia as distinct group. Gray, Syn. Fl. 

 N. Am. II. 1, 40 (1878). Dippel, Handb. Laubholzk. I. 410 (1889), with 

 Tsusia as distinct subgenus. Drude in Engler & Prantl, Nat. Pflan- 

 zenfam.IV. 1,37 (1889). Koehne, Deutsch. Dendr. 454 (1893), exclud- 

 ing Azaleastrum and Therorhodion. Rehder & Wilson in Sargent, PI. 

 Wilson. I. 516 (1913), excluding Chionastrum and Azaleastrum. Rehder 

 in Bailey, Stand. Cycl. Hort. V. 2937 (1916), excluding Azaleastrum. 



Shrubs or occasionally small trees with deciduous or half evergreen rarely 

 evergreen leaves, usually more or less strigose- or villose-pubescent, sometimes 

 glabrous, never lepidote-glandular. Flowers from a terminal bud, one or several 

 to many in umbel-like racemes. Corolla funnel-form to rotate, rarely campanu- 

 late, usually with a distinct often long and slender tube, rarely two-lipped and 

 divided partly almost to the base. Stamens 5 to 10, of unequal length. Ovary 

 5-celled, usually strigose and pubescent, rarely glabrous, never lepidote. 



The type section of the subgenus is Pentanthera and the type species Rhodo- 

 dendron luteum Sweet (Azalea pontica Linnaeus). In North America this subgenus 

 is represented by sixteen species. 



Our conception of the subgenus coincides exactly with that of Drude (I. c.), 

 while all other authors draw its limits narrower or wider, as shown in the syn- 

 onomy given above. In former publications I had included Azaleastrum and 

 Therorhodion in this subgenus, but as the inflorescens of these two groups is en- 

 tirely different from that of the type of this subgenus, I prefer to consider these 

 two groups as coordinate subgenera and restrict the sections belonging to Antho- 

 dendron to Tsutsutsi G. Don, Sciadorhodion Rehd. & Wils., Rhodora G. Don 

 and Pentanthera G. Don, of which the first two are exclusively Asiatic, while the 

 last two contain American and Asiatic species. It does not seem advisable to 



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