THE RHODODENDRONS
<mlyx, it is one of the most perfect plants of the whole, and in its characters of flower and.frnit is far more closely
allied to the typical or scarlet-flowered group, than is the section to which the Mowing belongs.
n . Moioiendron Falconer!, a white-flowered species, is eminently characteristic of the genus in habit, place of growth
and locality, never occurring below 10,000 feet. On the other hand it is peculiar in its ten-lobed corolla, numerom
stamens, and many-celled ovary, superb foliage and many-flowered capitula. This multiplication of parts and development
of foliage and trunk give it a striking appearance; but there is an almost total absence of calyx, an organ sufficiently
evident m other species. It is allied to a species discovered by the lamented Griffith in Bootan, the B. grande, Wight,
published in the Calcutta Joum. Nat. Hist. vol. viii. p. 176, [and since in Dr. Wight’s leones, vol. iv. p. 6. t. ISOS].-
m . A third white-flowered group contains but one Sikkim species, the B. argentemi, a very conspicuous tree at an
elevation of between 8,000 and 9,000 feet. In beauty of foliage it nearly equals the last mentioned (B. Falconen)
and the flowers are larger than in any but B. Balhoueia, and of (he same form as those of the scarlet group; the
stamens are of the normal number, but the ovarium is many-celled. Though evidently distinct, this species combines the
characters of most of the other groups. In sire of flower and colour, as already observed, it resembles B. DaBmsie,
as ,t does in its unusually membranous leaves;' in the colour of the flower, size of Mage, small calyx, and many-celled
ovarium, B. Falconer! ,~-wbile the number of stamens, general habit, silvery under-surface of leaf, &., connect it with
22. arboreum.3
IV. A singular set includes the dwarfish kinds to which B. cimabarinmi and B. Boylii belong. The flowers are
small, the corolla is subcoriaoeous, narrowed at the base of the tube, and its colour is a peculiarly dirty brick-red, somewhat
iridescent with blue in bud, and its lobes are rounded, subacute, not notched or wrinkled. The calyces are small,
coriaceous, and squamous in both; in one the lobes are remarkably unequal. In the number of stamens, cells of the
ovarium, fe., they agree with the usual characters of the genus.
V. Of the normal or typical group, indicated to be such by the number of species it contains, by the prevalence
of scarlet flowers, uniformity of corolla and number of parts, there are two subdivisions: one has a folly developed calyx,
m the other the oalyx is very small and coriaceous. B. laneifolium and B. barlatum represent the former section, in both
of which that organ is as conspicuous as in A M « , . B. arboreum, B. Wdllidm, and B. Campbell!*, belong to the
latter section. The species of this group known to me are all trees, of contracted range and gay flowers.
VI. The little B. elceagnoidee may be classed in another group; it is a ve^r alpine plant, of which I possess only
the foliage and fruit. Its scaliness (a character which seems most conspicuous in the smaller and more alpine species)
allies it to B. aimabarimm, but it is apparently single-flowered and ealyculate. -
The sub-Himalayan mountains are surely the centrum of this truly fine genus, distinguished by the number and
variety of its species and groups, by the great size and eminent beauty of several, which form conspicuous features in the
landscape over many degrees of longitude, .through a great variety of elevations, and clothe a vast amount of surface.
mpioil™ltS s h " I , ^ i S"i1 0" “ W“1 bS Se“ ' “ "Uh0"Sl1 “ B " * “ *■ — * H 8 especially in the deaae many-flowered
white and'scnly hencath^d r n T L p “ w Z lln “ ! ^ ^ ^ ^ — e, ea^data leaves,
thouJhmlleZ , h i Z T 0t ” me ” Kl hSrei k “ secies is the foliage tmly c o .-lc , conaceo« worn the better, ffiBS^BHBRS^^B^H
OF 8IKKIM-HIMALAYA. 11
The Neelgherries, Ceylon, and the Malay Archipelago contain, each, some species which prove the affinity of their
Floras to that of the Himalaya. The same is the case with the great mountains of Northern Asia, Central, Southern, and,
especially, Eastern Europe, the Ural, and Pontus. The genus extends even to the Polar regions, diminishing in the size
of the species and number as we recede from the Himalaya: in North America they appear again, though under a very
different aspect from that they present on the subtropical mountains of Asia.
Wide though this distinction is, it is far from uniform, the Himalaya itself offering most remarkable anomalies. My
friend Dr. Thomson (now engaged in a botanical mission to Thibet) informs me that the genus is not found in
Cashmere; nor, during all the wanderings of that intrepid and indefatigable naturalist in the Trans-Sutledge Himalaya
and Thibet, has he met with one representative of it. He detected, indeed, in the country south of the Chenaub, both the
22. arboreum and 22. campanulatvm, and which is probably their western limit.
In North-west India, the genus Rhododendron is first seen on the Kunawur hills, and advancing east, follows
the sub-Himalayan range for its whole length, the '‘species increasing in number as far as Sikkim and Bootan; thence
the genus is continued to the Mishmee hills, the eastern extremity of the range, crossing the Brahmaputra to that
lofty range which divides the water-shed of the Irawaddi from that of the Brahmaputra.
Though scarcely found, throughout this long line of upwards of 1,200 miles, below 4,000 feet, the Rhododendrons
still affect a warm and damp climate, where the winters are mild. The English naturalist, who is only familiar
with the comparatively small hardy American and European species, would scarcely expect this. A certain degree of
winter-cold and perpetual humidity is necessary; but the summer-heat is quite tropical where some of the genus
prevail, and snow rarely falls and never rests on several of those peculiar to Sikkim.
22. arboreum, according to Captain Madden, inhabits various localities between 3,000' and 10,000 feet: this is in
Kamaoon, where, of course, the genus would descend lowest; and the range is incomparably greater than that of any other
species, at least of those found in Sikkim.4 Dr. Griffith, after extended wanderings in Bootan, gives the limits of the genus
in that country as between 4,292 and 12,478 feet, which is a lower level by 3,000 feet than they are known to descend to
m Sikkim. In the extreme east of Assam, where the Himalaya itself diverges or sends lofty spurs to stem the
Brahmaputra, on the Phien Pass to Ava, Rhododendrons ascend from 5,400 to 12,000 feet, to the upper limit of
arboreous vegetation, and perhaps still higher.
During my limited excursions in Sikkim, I gathered eleven species (and I believe that more exist), a greater
number than Griffith obtained in Bootan; so that I cannot but regard this longitude as the head-quarters of the
genus in the Himalaya, and that chain as the especial region of the genus in the Old World. Here too I may
remark (as is the case with the Conifera of Tasmania and Gacteee of Mexico), the species are most limited in habitat,
where, numerically, the genus is the largest, the 22. arboreum, however, having a much wider range than any other
species found in Sikkim.
4 Dr. Hooker had here inserted "where R. arboreum is unknown,” that is, in Sikkim. But one of his own excellent figures, sent home
as representing a new species, is, I have no hesitation in saying, the true R. arboreum, coinciding entirely with the original figure of Sir James
E. Smith (Exotic Botany, Tab. 6), and with original specimens given me by the same distinguished botanist and existing in my own Herbarium.
or need we be surprised that Dr. Hooker should have fallen into this error, with few books and no authentic specimens to consult ;
especially when it is borne in mind that his eye had been accustomed to the plants that pass under that name in our gardens, but which
have been so hybridized by cultivators, either to increase their beauty or with the intention of rendering the offspring more hardy, that an
original plant or tree of Rhododendron arboreum is almost as rare in England as is the normal single-flowered state of the Corchorus
{Kerria) Japonica. Let it be further observed that other distinguished Botanists have confounded distinct species with the R. arboreum: I
ude especially to the plant so called by Dr. Wight of the Neelgherries (leones Plant. Ind. Orient, tab. 1201), which is the R. Nilagiricum
of Zenker Q?lant. Nilag. cum Ic., and of Bot. Mag. tab. 4881). No one who compares native specimens of these two plants can have
any hesitation in pronouncing them distinct. E d .
G 2