ERICACEAE. XLIII. RHODODENDRON. 



843 



D. Don, in edinb. phil. journ. 17. p. 152. Rhodoraceae, Juss. 

 gen. 158. Anthers 2 -celled. Ovarium free. Hypogynous disk 

 nectariferous, rarely ornamented with scales. Buds strobile- 

 like from imbricated scales. Leaves flat, having the extremity 

 of the midrib callous. 



XLIII. RHODODE'NDRON (from fiofav, rhodon, a rose, 

 and StvZpnv, dendron, a. tree ; in reference to the terminal bunches 

 of flowers, which are usually red). Lin. gen. no. 548. Schreb. 

 gen. no. 746. Gaertn. fruct. 1. p. 304. t. 63. Juss. gen. 158. 

 D. Don, in edinb. phil. journ. prod. fl. nep. p. 152. Azalea 

 species of authors. Rhodora, Lin. Chamaarhododendros,Tourn. 

 inst. t. 373. 



LIN. SYST. Penta-Decdndria, Monogynia. Calyx 5-parted. 

 Corolla somewhat funnel-shaped, or campanulate ; rarely rotate 

 or 5-parted ; limb 5-cleft, somewhat bilabiate ; upper lip the 

 broadest, and usually spotted. Stamens 5-10, usually exserted, 

 declinate ; anthers opening by 2 terminal pores. Capsule 5-celled, 

 5-valved, rarely 10-celled and 10-valved, as in R. arboreum, 

 with a septicidal dehiscence at the apex. Placentas simple, an- 

 gular. Seeds compressed, scobiform, winged. Shrubs or trees, 

 usually evergreen. Leaves alternate, quite entire, terminated 

 by a spacelate apex, or yellow gland. Flowers terminal, corym- 

 bose, showy. 



SECT. I. PO'NTICUM. Limb of calyx short, 5-lobed. Co- 

 rolla campanulate. Stamens 10. Ovarium 5-celled. Leaves 

 coriaceous, evergreen. 



1 R. PO'NTICUM (Lin. spec. 562.) 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. Tj . H. Native of Asia Minor, at 

 Pontus ; and of Gibraltar, Iberia, and Caucasus, in wet places in 

 beech and alder coppices. Pall. fl. ross. 1. p. 43. t. 29. Jacq. 

 icon. rar. 1. t. 78. Lam. ill. 364. Curt. bot. mag. 650. Leaves 

 sometimes becoming ferruginous beneath. Corolla purple, large, 

 with ovate, acute, or lanceolate segments. Calyx minute, 5- 

 toothed, somewhat cartilaginous. This is a very common plant, 

 of which there are a great many varieties. The most remark- 

 able are those with white, red, or bluish flowers, and striped 

 leaves. Tournefort has related that the flowers of this species 

 were reputed to impart a noxious quality to honey ; this Giilden- 

 stadt contradicts, and imputes it to Azalea Pontica. 



far. ft, obtusum (Wats, dendr. brit. t. 162.) leaves subcordate, 

 coriaceous, obtuse ; calyx very short, unequally and undulately 

 crenated. ^ H. Native of Pontus. Shrub 3-4 feet high. 

 Flowers purple. 



Var. y, myrtifbliitm (Lodd. bot. cab. 908.) leaves small ; 

 flowers purple. ^ . H. Native of Gibraltar. 



Var. S, Smilhii (Sweet, fl. gard. n. s. t. 50.) leaves lanceolate, 

 clothed with white tomentum beneath ; corymbs many-flowered ; 

 ovarium tomentose, 10-celled ; flowers of a rosy purple, ap- 

 proaching to crimson, elegantly spotted with black. ^ . H. A 

 hybrid, raised by Mr. Smith, of Coombe Wood, from the seed of 

 R . Ponticum, impregnated by the pollen of R. arboreum. 



Pontic Rhododendron or Rose-bay. Fl. May, June. Clt. 

 1763. Shrub 6 to 12 feet. 



2 R. MA'XIMDM (Lin. spec. p. 563.) arborescent ; leaves 

 elliptic-oblong, acute, convex, bluntish at the base, whitish or 

 rusty beneath, glabrous ; calycine segments oval-obtuse : seg- 

 ments of corolla roundish. T? . H. Native from Canada to 

 Carolina, on the mountains near rivulets and lakes. Sims, bot. 

 mag. 951. Lam. ill. 364. Schmidt, abr. t. 121. Mill. fig. 229. 

 Catesb. car. 3. t. 17. f. 2. Flowers pale red, in umbellate 

 corymbs, studded with green, yellow, or purple protuberances. 



Largest Rhododendron or American Rose-bay. Fl. June, 

 Aug. Clt. 1736. Shrub 10 to 15 feet. 



3 R. FURPU'REUM ; arboreous ; leaves large, oblong-elliptic, 

 flattish, acute, bluntish at the base, green and glabrous on both 

 surfaces ; segments of corolla oblong, obtuse. Fj . H. Native 

 of Virginia and Carolina, on the highest mountains, near lakes. 

 R. maximum y, purpureum, Pursh, fl. amer. sept. 1. p. 297. 

 Flowers large, purple. Calycine segments obtuse. This shrub 

 approaches near to R. Ponticum, but it differs in its foliaceous 

 calyx, and otherwise. It grows to an immense size ; its stem 

 is often found 18 inches and more in diameter, and its foliage 

 triple the size of any other species. 



Parp/e-flowered Rhododendron. Fl. May, June. Clt. ? Tree 

 20 feet. 



4 R. PU'RSHII : arborescent ; leaves cuneate-lanceolate, flat, 

 glabrous, tapering gradually to the base, paler beneath ; caly- 

 cine segments oval, obtuse ; segments of corolla roundish- 

 oblong. !?. H. Native of New Jersey and Delaware, in 

 shady cedar swamps. R. maximum ft, album, Pursh, fl. amer. 

 sept. 1. p. 297. Flowers white, smaller than those of R. 

 mdximum. 



Pursh' s Rhododendron. Fl. June, Aug. Clt. 1811. Shrub 

 6 to 8 feet 



5 R. MACROPHY'LLUM (D. Don, mss. in herb. Lamb.) leaves 

 lanceolate, acute, glabrous on both surfaces, as well as the pe- 

 duncles, rounded at the base ; ovarium bristly. Vj . H. Native 

 of the north-west coast of America, where it was collected by 

 Menzies. Petioles an inch long. Leaves 7-8 inches long. 

 Flowers copious, smaller than those of R. mdximum, white. Caly- 

 cine lobes short, rounded. Filaments glabrous. 



Long-leaved Rhododendron. Shrub. 



6 R. CATAWBIE'NSE (Michx. fl. bor. amer. 1. p. 258.) leaves 

 short-oval, rounded, and obtuse at both ends, glabrous, of a 

 different colour beneath ; ealycine segments elongated, oblong. 

 Tj . H. Native on the high mountains of Virginia and Caro- 

 lina, particularly on the head waters of the Catawba River. 

 Sims, bot. mag. 1671. Lodd. bot. cab. 1176. Flowers purple, 

 disposed in umbellate corymbs. 



Var. ft, Russellianum (Sweet, fl. gard. n. s. t. 91.) leaves oblong, 

 finely tomentose beneath ; corymbs many-flowered ; flowers of 

 a bright rosy red, approaching to crimson. ^ . H. A hybrid, 

 raised from the seed of R. Catawbiense, impregnated by the 

 pollen of R. arboreum, by Mr. Russell, of Battersea. 



Catanba Rhododendron. Fl. June, Aug. Clt. 1809. Shrub 

 4 feet. 



7 R. BRACHYCA'RPUM (D. Don, mss. in herb. Lamb.) leaves 

 elliptic-oblong, obtuse, clothed with rusty tomentum beneath, 

 rounded at the base ; ovaries 5-celled, and are as well as the 

 peduncles hairy. ? ^ . H. Native of Japan. Petioles half 

 an inch long. Leaves 3 inches long. Calycine lobes very 

 short, roundish, revolute, callous. Style elongated. Stigma 

 clavate. 



Short-fruited Rhododendron. Shrub. 



8 R. CHRYSA'NTHUM (Lin. 

 syst. 405. suppl. 237.) leaves 

 acutish, attenuated at the base, 

 oblong, glabrous, reticulately 

 veined, and of a rusty colour 

 beneath ; flowers and buds 

 clothed with rusty tomentum ; 

 pedicels hairy ; calyx hardly 

 any ; segments of the corolla 

 rounded ; ovarium tomentose. 

 1? . H. Native of Siberia, on 

 the highest mountains, and of 

 Caucasus. Pall. itin. append. 

 p. 729. no. 87. t. N. f. 1-2. 

 fl. ross. 1. p. 44. t. 30. Woodv. 

 med. bot. 433. t. 149. Plenk, 



5 p 2 



FIG. 141. 



