584 ARBORETUM ET FRUTICETUM BRITANNICUM. 



10-celled and 10-valved as in 7?. arboreum, with a septicidal clehiscence at 



the apex. Placentas simple, angular. Seeds compressed, scobifonn, 



winged. (Don's Mill.) 



Leaves simple, alternate, exstipulate, deciduous, or evergreen ; quite 



entire, terminated by a sphacelate apex, or yellow gland. Flowers terminal, 



corymbose, showy. Shrubs, usually evergreen ; natives of Europe, Asia, 



and North America. 



In the Azalea division of this genus the species are almost entirely decidu- 

 ous, with quite entire alternate leaves, terminated by a withered tip, or yellow 

 gland ; and terminal, corymbose, showy flowers. All the species thrive best 

 in sandy peat, kept rather moist ; and they are propagated chiefly by layers 

 and seeds. 



i. Ponticum D. Don. 



Sect. Char. Limb of calyx short, 5-lobed. Corolla campanulate. Stamens 10. 

 Ovarium 5-celled. Leaves coriaceous, evergreen. (Don's Mill., iii. p. 843.) 



* 1. R. PO'NTICUM L. The Pontic Rhododendron, or Rose Bay. 



Identification. Lin. Sp., 562. ; Don's Mill., 3. p. 843. 



Engravings. Pall. Fl. Ross., 1. p. 43. t. 29. ; Bot. Mag., t. 650. ; and our fig. 1100. 



Spec. Char., fyc. Leaves oblong-lanceolate, glabrous on 

 both surfaces, attenuated towards the thick petioles, 

 with a streak on the upper surface, of a wide lanceolate 

 form. Racemes short, corymbose. Leaves sometimes 

 becoming ferruginous beneath. Corolla purple or 

 purplish pink, large ; with ovate, acute, or lanceolate 

 segments. Calyx minute, 5-toothed, somewhat carti- 

 laginous. (Don's Mill.) An evergreen shrub ; Pontus 

 (now Armenia), in Asia Minor. Height 10 ft. to 

 12ft. Introduced in 1-763. Flowers purple; May 

 and June. Capsules brown ; ripe in September. 110 ^ fl . p<5nticum . 



Varieties. 



M.R. p. 2 obtiisum Wats. Dend. Brit. t. 162., Don's Mill., has the leaves 

 subcordate, coriaceous, obtuse, and the calyx very 

 short, and unequally and undulately crenated. It 

 grows from 3 ft. to 4 ft. high, and has purple flow- 

 ers. Wild in Armenia. 



a R. p. 3 myrtifolium Lodd. Bot. Cab. t. 908. (and our 

 fig. 1101.), Don's Mill., has the leaves small, and 

 the flowers purple. It is a native of Gibraltar. 

 R. p. 4 Smithn Swt. Brit. Fl.-Gard. n. s. t. 50., 

 Don's Mill., has the leaves lanceolate, and clothed 

 with white tomentum beneath ; corymbs many- 

 flowered ; ovarium to- 

 mentose, and 10-celled. 

 The flowers are of a rosy purple, ap- 

 proaching to crimson, elegantly spotted 

 with black. A hybrid, raised by Mr. Smith, 

 at Coombe Wood, from the seed of R. 

 ponticum, impregnated by the pollen of 

 R. arboreum. 



R. p. 5 Ldw'ii Gard. Mag. vol. xi. p. 190. 

 Corolla white ; the upper segments marked 

 by a few dull scarlet spots. This is a 

 most striking variety, originated by M. 

 Jacob Makoy. 

 R. p. 6 azaleotdea ; R. azaleoides DesJ. ; 



R. p. /3 subdeciduum Andr. Bot. Rep. t. 1102 . . p . Ma!eeid 



