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FLORA AND FAUNA OF UTTARAKHAND

The Himalayan phenomenon of flora and fauna has been
rightly described by Salim AH in these words : "One of the-
things that makes trekking in the Himalayas so particularly deli-
ghtful is surely the constant change in the character of the plants
and birds that one meets as one climbs higher and higher, and
passes from one zone of altitude to another."
The controlling effect of mountain chains and hill ranges on
local climate and vegetation, and, therefore, on the distribution
of animal life, is wellknown. The Himalayas stretches across
our northern frontier like a gigantic wall, cutting off the Indian
plains of the Gangetic valley from the high plateau of Tibet and
Central Asia. They bar the northward passage of the moisture
laden wind currents, driven up seasonally from the south-west
through the Indian Sea and Bay of' Bengal to the land beyond.
This character offers an outstanding example of the role that
mountain ranges play in the character and local distribution of
animal life and vegetation. Botanists have long remarked upon
the general similarity of the flora of the higher slopes of such
widely separated mountain ranges as the Himalayas, the N2gms
and other hills of south-west India.
Truely, the Himakyas exercise profound influence on the