arboretum it is named R. ponticum macrophyllum. The year of its intro

duction into British gardens is uncertain ; nor has it been inuch cultivated. . 4. R. Pu’rsun G. Don. Pursh's Rhododendron, or American Rose Bay. Identification. Don's Mill., 3. p. 843. Synonyme. R. máximum 3 album Pursh Fl. Amer. Sept., 1. p. 297. Spec. Char., 8c. Arborescent. Leaves cuneate-lanceolate, flat, glabrous, tapering gradually to the

base, paler beneath. Calycine segments oval, obtuse. Segments of corolla roundisb-oblong. Flowers white, and smaller than those of R. máximum. (Don's Mill., iii. p. 843.) A native of New Jersey and Delaware, in shady cedar swamps; where it forms a shrub growing from 6 ft to 8 ft. high, flowering from June to August. It was introduced in 1811, but is not common in col. lections.

5. R. CATAWBIE'NSE Michx. The Catawba Rhododendron. Identification. Michx. Fl. Bor. Amer., 1. p. 258. ; Don's Mill., 3. p. 843. Lodd. Cat, ed. 1836. Engravings. Bot. Mag., t. 1671. ; Lodd. Bot. Cab., t. 1176.; and our fig. 933. Spec. Char., 8c. Leaves short-oval, rounded, and obtuse at both ends, gla

brous, of a different colour beneath. Calycine segments elongated oblong. Flowers purple, disposed in umbellate corymbs. (Don's Mill., iii. p. 813.) It is a native of the high mountains of Virginia and Carolina, particularly near the head waters of the Catawba River, where it is a shrub, about 4 ft. high, flowering from June till August. Introduced in 1809, and now one of the most

933 common species in gardens. It is of more robust growth than either R. pónticum or R. máximum, but, in other respects, seems intermediate between them.

There are many hybrids in cultivation between it and the former species, though without names; partly from the minuteness of the shades of distinction between them, and partly from their having been raised by nurserymen who had not sufficient influence or energy to bring them under the notice of botanists. There are some very distinct varieties in the Knaphill Nursery.

Plants vary in price from 1s. to 5s. Varieties. . R. c. 2 Russelliànum Brit. Fl.-Gard., 2d s., t. 91., Don's Mill., iii.

p. 843.—Leaves oblong, finely tomentose beneath. Corymbs manyflowered. Flowers of a bright rosy red, approaching to crimson. A hybrid raised from the seed of R. catawbiense, impregnated by the pollen of R. arboreum, by Mr. Russell of Battersea. It is a very splendid variety, but somewhat tender. R. c. 3 tigrinum Hort. is a variety with a corolla much resembling

that of R. c. Russellianum, but with obvious spots on the inside.

6. R. CHRYSA'Nthum L. The golden-flowered Rhododendron.
Identification. Lin. Syst., 405., Suppl., 237. ; Don's Mill., 3. p. 843. ; Lodd. Cat., ed. 1836.
Synonyme. R. officinale Salisb., p. 121. t. 54.
Engravings. 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. ; Salisb. Par. Lond., t. 80. ; Gmel. Sib., 4. t. 54. Spec. Char., 8c. 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. Branches decumbent, beset with rusty stipula-formed scales. Flowers handsome, large, drooping, revolute, rather irregular, yellow. Stigma 5-lobed. (Don's Mill. iii. p. 844.) It is a native of Siberia, on the highest mountains; and of Caucasus, where it forms a low evergreen undershrub, growing from

6 in. to 1 ft. in height, and flowering in June and July. Pallas found it in Kamtschatka, growing in the hollows at the foot of mountains, and by the margins of stagnant pools. It is indigenous through the whole of Siberia, from Lake Baical to the river Lena; thriving equally on the tops of mountains covered with snow, and in the peat bogs of the valley. It was introduced in 1796, but is not common in collections, being very difficult to keep. The best plants, in the neighbourhood of London, are at the Knaphill Nursery, Woking, Surrey. This shrub has a place in the British materia medica, and is frequently prescribed as a substitute for colchicum, in the cure of the gout and rheumatism. Its value as a medicine was first discovered by Gmelin and Steller, when travelling in Siberia, who inform us that the Siberians have recourse to it in rheumatic and other affections of the muscles and joints. The manner of using the plant by the Siberians is, by putting two drachms of the dried leaves in an earthen pot, with about 10 oz. of boiling water, and keeping it nearly at a boiling heat for a night : this they take in the morning, and, by repeating the dose three or four times, generally effect a cure. It is said to occasion heat, thirst, a degree of de lirium, and a peculiar sensation of the parts affected. (Woodville.

7. R. CAUCA'Sicum Pall. The Caucasian Rhododendron.
Identification. Pall. Fl. Ross., 1. p. 46. t. 30.; Don's Mill., 3. p. 844. ; Lodd. Cat., ed. 1855.
Engravings Bot. Mag., t 1145.; and our fig. 934.
Spec. Char., 8c. Leaves ovate-oblong, clothed with

rusty tomentum beneath, rugged and green above.
Peduncles hairy. Bracteas elongated, tomentose.
Ovarium downy. Root creeping. Branches pro-
cumbent. Flowers purple or white, disposed in
umbellate corymbs.

Corollas rotate, with wavy, rounded segments. (Don's Mill., iii. p. 844.) A native of Caucasus, on high rocks, near the limits of perpetual snow; where it forms an evergreen shrub, growing ift. high, and flowering in August. It was introduced in 1803, but is rare in collections. There are plants at Messrs. Loddiges's, and at Knaphill.

934 Varieties. The following hybrids are among the handsomest rhododendrons in cultivation : * R. c. 2 stramineum Hook. Bot. Mag., t. 3422., has straw-coloured co

rollas. A plant of this variety in the Glasgow Botanic Garden, in April, 1835, was 2 ft. high, and 3 ft. in diameter, with the extremities of its fine leafy branches terminated with clusters of large, beautiful, straw-coloured flowers. The climate of Scotland seems to suit this, and some of the other species found in the coldest parts

of the Russian empire, better than that of the south of England. • R. c. 3 pulcherrimum Lindl. Bot. Reg., t. 1820. f. 2., is a hybrid, ob

tained by Mr. Waterer of the Knaphill Nursery, between R. arbo reum and R. caucásicum, in 1832. It is described as a most beau

tiful variety," quite hardy, and an abundant flowerer. • R. c. 4 Nobleánum Hort., Bot. Reg., t. 1820. f. 1., is a hybrid, very

much like the preceding one in all respects, except that its flowers

are of a deep and brilliant rose colour.

a

Segments of corolla ovate, a little undulated. Flowers pink, disposed in umbellate corymbs. Corollas funnel-shaped. Capsules elongated. (Don's Mill., iii. p. 844.) It is a native of Carolina, on the mountains, particularly at the head waters of the Savannah er, where it forms an evergreen shrub, growing to the height of 4 ft., and flowering in July and August

. Introduced in 1786, and frequent in collections. Variety.

935 R. p. 2 màjus Ker, Bot. Reg., t. 37.—Leaves

and flowers larger.

- 9. R. FERRUGI'NEUM L. The rusty-leaved Rhododendron. Identification. Lin. Sp., 562. ; Don's Mill., 3. p. 844. ; Lodd. Cat., ed. 1836. Engravings. Jacq. Obs., 1. p. 96. t. 16.; Fl. Austr., 3. 6. 255. ; Lodd. Bot. Cab., 65. ; Lob. Icon., 366. ;

and our fig. 936. Spec. Char., fc. Leaves oblong, attenuated at both ends, glabrous, shining

. and green above, but thickly beset with rusty dots beneath. Calycine segments dentately ciliated. Leaves like those of the box tree; when young, ciliated with a few hairs at bottom. Flowers of a beautiful rose colour or scarlet, disposed in unibellate corymbs, marked with ash-coloured or yellow dots. Corollas funnelshaped. Filaments hairy at bottom. (Don's Mill., iii. p. 844.) It is a native of the Alps of Europe, as of Switzerland, Austria,

936 Savoy, Dauphiné, and Piedmont; where this species and R. hirsùtum terminate lig. neous vegetation, and furnish the shepherds with their only fuel. It is an evergreen shrub, growing about 1 ft. high, and

flowering from May to July, Introduced in 1752, and frequent in collections. Variety. BR. f. 2 álbum Lodd. Cat., ed. 1836, has white flowers.

# 10. R. (? F.) HIRSU'TUM L. The hairy Rhododendron. Identification. Lin. Sp., 562.; Don's Mill., 3. p. 844. Engravings. Jacq. Austr., 1. t. 98.; Bot. Mag., i. 1853. ; Lodd. Bot. Cab., t. 479. ; Lob. Icon., 468.; and

B our

fig. 937. Spec. Char., &c. Leaves ovate-lanceolate, or elliptic,

acutish, ciliated, with rusty hairs on the margins, glabrous above, dotted and hairy beneath. Calycine segments fringed, bearded. Flowers pale red or scarlet, disposed in umbellate corymbs.Corollas funnelshaped. (Don's Mill., iii. p. 844.). It is a native of the Alps of Europe, and of Switzerland, Austria, Styria, Dauphiné, &c.; where it forms a shrub growing from 1 ft. to 2 ft. high, flowering from May to July. Introduced in 1656, and possibly only a variety of the preceding species.

937 Variety.

R. (f.) h. 2 variegatum has the leaves edged with yellow.

purple, size of those of R. dådricum, disposed in umbellate corymbs. Calyx purple. Filaments bearded at the base. Stigma capitate. (Don's Mill., iii. p. 844.) A native of Nepal, in Gossain. than ; where it is a shrub, growing from half a foot to one foot in height; but it has not yet flowered in England, where it is considered as a frame shrub. It was introduced in 1825; but we have not seen the plant.

R. macrophyllum D. Don (G. Don's Mill., iii. p. 843.) is a native of the north west coast of North America, where it was collected by Mr. Menzies; and there are specimens in Mr. Lambert's herba. rium ; but the plant has not yet been introduced. The petioles of the leaves are 1 in., and their disks from 7 in. to 8 in., long; and the flowers are smaller than those of R. máximum, and white.

§ ii. Lepipherum D. Don. Derivation. From lepis, a scale, and phero, to bear; leaves covered with small scales. Limb of calyx dilated, 5-lobed. Corolla campanulate or rotate. Stamens 10. Ovarium 5.celled. Leaves membranous, sometimes deciduous, but generally persistent. Shrubs, natives of Europe, North America, and the Himalayas.

12, R. LAPPO’NICUM Wahl. The Lapland Rhododendron. Identification. Wahl. Fl. Suec., p. 249. ; Don's Mill., 3 3. p. 845. Synonymes. Azalea

lappónica Lin. Fl. Suec., p. 64., Sp., t. 214., Fl. Lapp., ed. Smith, p. 59. L. 6. f. 1., Hook. Bot. Mag., 3106. ; A. ferruginea Hort. Engraving. Our fig. 938. Spec. Char., fc. Shrub, branched, procumbent. Branches divaricate. Corollas rotately funnel-shaped. Young branches obscurely pubescent, warted.

eaves oblong, obtuse, stiff, beset with honeycomblike dots, yellowish and scaly beneath ; deep green above; and pale green, and at length yellowish, beneath; thickly beset with hollow dots on both surfaces, which are covered by umbilicate permanent scales. Flowers crimson, disposed in umbellate corymbs, 5–6 to. gether, surrounded by large dotted scales, or bracteas. Calyx covered with yellow scales, ciliated. Segments of corolla unequal, and undulated. Stamens 5—8, equal in length to the corolla. Stigma capitate, 5-lobed. Filaments hairy at the base. (Don's Mill., iii. p: 845.) It is a native of the arctic regions of Europe, Asia, and North

938 America, where it forms a procumbent shrub, flowering in July. Introduced in 1825, but rare in collections.

# 13. R. DAU'Ricum L. The Dahurian Rhododendron. Identification. Lin. Sp., 562.; Don's Mill., 3. p 845. ; Lodd. Cat., ed. 1836. Engravings. Pall. F1. Ross., 1. p. 47. t. 32. ; Andr. Bot. Rep., t. 4.; Bot. Mag., t. 836.; Lodd. Bot.

Cab., t. 605. ; Amm. Ruth., 181. t. 21. Spec. Char., &c. Leaves deciduous, oblong, attenuated at both ends, glabrous, but sprinkled with rusty scales, especially beneath.

Limb of calyx 5-toothed. Corollas rotate. Roots knobbed, abounding in fibres. Stems twisted and knobbed in the wild state. Petioles downy. Leaves dotted on both surfaces, but ferruginous beneath. Before they fall in autumn, they become of a dusky red colour. The flowers rise before the leaves, from the tops of the branches, from buds which are composed of concave downy scales. Corolla purple. (Don's Mill., iii. p. 845.)' It is a native of Siberia, peculiar to the alpine tracts of Eastern Asia. It appears first at the mouth of the river Yenissei ; and beyond that, especially from the river Uda, in the pine woods, it begins to be common; but about the Baikal it is most abundant, and extends through the deserts of the Mongols to China and Thibet. At the Lena it becomes more rare; and beyond that it is much dwarfer, with more slender flowers, and narrower leaves. Pallas informs us that the leaves are narcotic, fragrant, and possess the odour of those of Lèdum palustre; and that, like it, they are used to drive away bugs, and also as tea. The fruit, he says, is employed for intoxicating fish, but in what manner, or for what purpose, he does not state. A shrub, growing from 2 ft. to 6 ft. high ; flowering from December to March. Introduced in 1780, and frequent in collections. 939

Variety. & R. d. 2 atrovirens Ker, Bot. Reg., t. 194., Bot. Mag., t. 1888., Lodd.

Cat., ed. 1836, is subevergreen. Leaves deep green, and shining

above. It is a native of Siberia. R. lepidotum Wall. (Royle Illust., p. 260. t. 64. f. 1.; Don's Mill., 3. p. 845.) is a native of Nepal, with the habit of R. däuricum, but with leaves of a thinner texture, and with every part of the plant beset with ferruginous scale-like dots. It grows to the height of 2 ft. or 3 ft, but has not yet been introduced.

§ iii. Chamæcistus D. Don. Derivation. From chamai, on the ground, and cistus, the rock rose ;

plants with the habit of species of Helianthemum. Limb of calyx foliaceous, 5-cleft. Corolla rotate. Stamens 10. Ovarium 5-celled. Di. minutive, prostrate, evergreen shrubs, with small membranous leaves. h 14. R. CAMTSCHA'Ticum Pall. The Kamtschatka

Rhododendron.
Identification. Pall. Fl. Ross., 1. p. 48. t. 33. ; Don's Mill., 3. p. 845.
Engravings. Gmel. Sib., 4. p. 126. No. 13. ; and our fig. 940.
Spec. Char., 8c. Leaves obovate, acutish, 5-nerved,

naked, ciliated, peduncles hairy, usually twin. Caly-
cine segments ciliated, foliaceous. Corollas purple,
rotate. (Don's Mill., iii. p. 845.) A prostrate shrub,
flowering in July; a native of Kamtschatka and the
Aleutian Islands, in muddy places on the mountains.
Introduced in 1802, but rare in British gardens. There 940
are plants at Messrs. Loddiges's.

h 15. R. CHAMÆCI'stus L. The Ground-Cistus Rhododendron.
Identification. Lin. Sp., 562. ; Don's Mill., 3. p. 854. ; Lodd. Cat., ed. 1836.
Engravings. Jacq. Fl. Austr., 3. t. 217. ; Bot. Mag., t. 488. ; Bot. Cab., t.

1491.; Michel. Gen., 225. t. 106. ; Pluk. Phyt., t. 23. f. 4.; and our fig. 941. Spec. Char., fc. Leaves oblong-lanceolate, attenuated at

both ends, stiffish, glandularly ciliated. Peduncles usually twin, and, as well as the calyxes, beset with glandular hairs. Corollas rotate, pale purple. A dwarf tufted shrub, with small leaves, about the size of those of a species of Helianthemum. (Don's Mill., iii. p. 845.)

941 A native of the Alps of Europe, as of Austria, Carniola, Mount Baldo, and near Salzburg; and in Eastern Siberia. It grows about half a foot high, and flowers in May and June. Introduced in 1786;

but seldom to be met with in British gardens. Having very small leaves, it may without impropriety be introduced in such ericetums as admit Dabæ cia, and other genera resembling the hardy heaths in general appearance.

9 iv. Pentanthèra D. Don. Derivation. From pente, five, and anthēra, an anther; flowers pentandrous. Sect. Char. Limb of calyx short, 5-lobed. Corolla funnel-shaped. Stamens 5.

Ovarium 5-celled. Leaves deciduous. This group includes the hardy azaleas of the gardens, which have mostly deciduous leaves, and are quite distinct in their appearance from the plants of the preceding groups of this genus, which are all evergreen and subevergreen. We, therefore, think that it would be much better to constitute this section the genus Azalea, and retain as names for the species those in common use. The convenience of such an arrangement, in gardens where there are so many hundred varieties of Azalea, where so many are being annually produced, and where these varieties are so much in demand, will be felt by every gardener. It may be perfectly true, according to the usual principles of forming genera, that Azalea and Rhododendron are not generically distinct; but, when the adherence to this rule of science, as it may be called, leads to so much confusion and inconvenience as in the present case, in practice, we certainly