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the east to the west of the country, the latter scarcely occurs west 
of long. 112°. In Central and Western China, with the exception 
of the above two species and R. Mariesii, no Rhododendron occurs 
below 4000 ft. Above this altitude they occur in woods and 
forests in increasing numbers, reaching their optimum at about 
11,000 ft. In the regions traversed by me, 15,500 ft. was 
the altitudinal limit of the genus. Farther west, however, it is 
somewhat higher. Rhododendrons are social plants, and at certain 
altitudes form immense thickets. t low levels, miles of the 
hillsides often are ablaze with the scarlet F. indicum. Up to 
9000 ft. the Rhododendrons occur in constantly increasing 
numbers, in company with mixed dicotyledonous trees and shrubs 
and conifers. Above 9000 ft. they form the predominant shrubby 
vegetation, either as undergrowth in the conifer forests or above the 
tree limit, where they form impenetrable thickets. In late May and 
June these areas present a scene of indescribable beauty. 
In stature, Chinese Rhododendrons vary from tiny plants six 
inches high (R. nigro-punctatum) to trees 40 feet high (R. calophy- 
tum). But omitting extremes, they are as a rule bushes from 
6-20 feet high and as much in diameter 
Epiphytic species are rare, and only two, R. dendrocharis and 
- moupinense, have been met with. The first-named is very 
common on coniferous trees, especially on Abies Fargesii and Tsuga 
yunnanensis. &, moupinense occurs on evergreen oaks and dicoty- 
ledonous trees generally. Both species are dwarf and twiggy, and 
at a distance are suggestive of species of Loranthus, But whilst 
true epiphytes are rare in the depths of coniferous forests, a large 
percentage of the Rhododendron bushes occur growing on the 
rotting trunks of fallen forest giants. 
In colour the Chinese Rhododendrons range from the purest white, 
the clearest and richest yellow, the varying shades of red, the 
deepest and richest shades of crimson, to the darkest purple. In size 
the flowers may vary in diameter from less than a third of an inch 
(R. anthopogonoides) to three inches, R. excellens. With rare excep- 
tions (R. sinense, R. indicum, R. micranthum, R. Mariesii, and 
possibly a few others) all the species are remarkably local, whether 
in longitudinal, latitudinal or altitudinal range. With the exception 
of R. stamineum none of the Hupeh species occur in western 
Szechuan. Very few of Pére Delavay’s Yunnan species are to be 
found even in South Szechuan although the regions are contiguous, 
The species collected by Pére Bodinier in Kweichau Province are 
nearly all different from those collected in the adjoining provinces 
specimens, made by Mr. G. Forrest and presented by Dr. Bayley 
Balfour, F.R.S. i 
16106 A2 
