INTRODUCTION 
xlvii 
the ridges are bare and open, while the more elevated portions are 
covered with forest. Probably the cause of this is the greater 
humidity of the higher slopes, which attract the rain clouds, while 
the lower ranges are dry. The currents of air which sweep up the 
valleys may ^ also in part be the cause of the bareness of the ridges 
opposite their summits. 
At Theog, nearly eight miles from Fagu, the cultivation is 
principally of barley, which is sown in early spring, and reaped 
in the beginning or middle of June, according to the season. 
Beyond Theog the road is covered with brushwood on the left 
hand, but bare on the right. The highest part of the road is 
about two miles beyond Theog, and has an elevation of about 
9,000 feet. The northern face of this hill is prettily wooded with 
the holly -leaved oak. 
The ravine immediately below Mattiana is crossed at an eleva- 
tion probably a little above 6,000 feet, as the trees of the temperate 
region, such as the holly -leaved oak [Quercus dilatata ] and woolly 
oak [< Q . incana\, Andromeda , and Rhododendron, continue to the 
very bottom of the descent ; and Pinus excelsa is common on the 
eastern slope, a little way above the stream. On the banks of 
this there were a few trees of an Acacia [ Albizzia mollis ] common 
in the low$r forests. I observed also a laurel, an olive, Rhus, 
and the common Toon, Cedrela Toona [more likely C. serrata ], all 
indicative of the commencement of a subtropical vegetation, 
which no doubt must be abundant on its banks a very few miles 
further down. Few of the plants observed in the valley were dif- 
ferent from those common around Simla ; a species of Caragana, 
a leguminous genus abundant in Siberia and in the interior and 
more dry parts of the Himalaya, was perhaps the most inter- 
esting. 
The ascent from the ravine was well wooded in its lowest part 
with oak and pine. A few trees of a very handsome poplar, 
Populus ciliata, a tall, widely branching, large-leaved tree, 
occurred in its lower part, as did also Benthamia fragifera [ Cornus 
capitata ] and a yew, apparently undistinguishable from the com- 
mon European species. 
The ripening of the apricot in a valley, among forest, at an 
elevation of 7,000 feet indicates an undoubted diminution of the 
rainfall. Very little change, however, is observable in the wild 
vegetation till the upper part of the last steep ascent, when a 
number of species make their appearance which are strangers to 
the more external ranges. A species of hazel [ Corylus Colurna ], 
as a tree, and Lappa, Achillea, Leonurus, Cheiranthus, and Rumex 
acetosa, as herbaceous plants, may be mentioned as instances, as 
