16G JOURNAL OF THE ARNOLD ARBORETUM [vol. vr 



late, 7-12 cm. long, 1-3 cm. wide, subacute or obtuse, base narrowed, 

 cuneate, upper surface lustrous green, lower densely covered with pale 

 gray crustaceous indumentum, midrib impressed above, prominent 

 below, secondary veins inconspicuous; petiole 1-1.5 cm. long, glabrous. 

 Flowers 10-20 in rounded umbellate corymbs; rhachis 1.5-2 cm. long; 

 outer bud-scales glabrous, inner densely clothed with soft appressed 

 tomentum; pedicels 1-3 cm. long, clothed with short curled rufous brown 

 pubescence; calyx annular, pubescent, with 5 minute broad rounded or 

 triangular teeth; corolla white or pink with few purple-brown honey- 

 guides, wide-funnelform, about 3-4 cm. long, 3.5-4.5 cm. wide, 5-lobed, 

 lobes 1.5 cm. long, rounded or emarginate; stamens 10-12, included, fila- 

 ments unequal, flattened and villose at base; pistil equalling the corolla, 

 ovary ovoid, 4 mm. long, densely clothed with short appressed gray- 

 brown pubescence, style glabrous, stigma capitate lobed. Fruit not seen. 



Habitat: Formosa, central mountains between 1500 and 2000 in. altitude. 



The species is characterized by the pale gray under surface of its 

 leaves and by its pubescent pedicels, calyx and ovary. It is most closely 

 related to R. hypoglaucum Ilemsl., native of central China, which has 

 glandular and less strongly pubescent pedicels and calyx, and a glabrous, 

 narrow-ovoid ovary. Living plants of these two species are quite dif- 



ferent in appearance though their morphological differences appear 

 slight when written down. 



In mixed forests, rich in species of Oaks, at 5500 ft. altitude near 

 Tentana in Shinchiku prefecture, I found R. formosanum Ilemsl. in full 

 flower on April 6, 1918, and the above description is based on this mate- 

 rial. The species was quite common and often of large size and tree-like 

 in habit. The rounded trusses are of good size and the flowers white 

 or pink in color. First discovered by Augustine Henry in the southern 

 part of the island in 1894 this Rhododendron has since been found in 

 several districts and appears to extend along the central ranges from 

 south to north. It is the most beautiful species of its section known to 

 grow in Formosa and well worth introducing into gardens. 



7. Rhododendron simiarum Ilance in Jour. Hot. xxn. 22 (1884). — 

 llemsley in Jour. Linn. Soc. xxvi. 30 (1889). — Dunn & Tutcher in Kew 

 Bull. Misc. Inform, add. ser. x. 155 (Fl. Kwangtung & Hongk.) (1912). 



Rhododendron Ford it Hemsley in Kew Hull. Misc. Inform. 1S!>4, 5; in Bot. 

 Mag. cxxxil. t. 8111 (1900).— Bean in Flora & Sylva, m. 163 (1905).— 

 Dunn & Tutcher in Kew Bull. Misc. Inform, add. ser. x. 155 (Fl. Kwangtung 



& Hongk.) (1912).— Millais, Rhodod. 108 (1917); n. 143 (VJ'2l). 

 Bush about 2 m. tall, branches numerous, stout, when young clothed 

 with gray floecose tomentum, glabrescent; bud-scales glandular. Leaves 

 crowded at ends of branches, coriaceous, oblanceolate-oblong to lanceo- 

 late or oblong-lanceolate, 4-9 cm. long, ^ 15.5 cm. wide, obtuse or rounded, 

 base narrowed to petiole, upper surface of young leaves clothed with 

 floecose gray tomentum, later glabrescent, lustrous dark green, reticulate; 

 lower surface densely clad with pale gray or dun-colored crustaceous 



