STEWART: FLORA OF LADAK, WESTERN TIBET 573 
GEOLOGY 
Although the geology of Ladak is not very well known, the 
following interesting facts are gathered from Burrard and Hayden 
(8) — 
‘All the geologic series is reproduced in Tibet from almost the earliest till 
modern times. Tibet, counting everything behind the great Himalayan range, 
consists of more than 20,000 feet of sediments, almost entirely of marine origin an 
represented by such rocks as slate, sandstone, conglomerate and limestone. Along 
to the Mediterranean. The region kept subsiding and subsiding and later was ele- 
vated. In Cambrian timesit is beiieved that Tibet and North America were joined, 
as the fossils are similar while they differ from those of Europe. At the close of the 
Cambrian this sea (the Tethys of Suess) linked up with the Palaeozoic sea of Europe. 
5 1 
“Crystalline and met r granite, gneiss and schist cover the greater 
part of northern Kashmir, including Baltistan and west to the mountains of Afghan- 
istan. To the east they run through northern Ladak. In eastern Kashmir they 
constitute much of Zanskar.”’ 
In view of the agreement among geologists that the elevation 
of the Himalayas has taken place in very recent time, and that 
Tibet, including Ladak, was under a sea which piled up tre- 
mendous sedimentary deposits until the Tertiary period, the flora 
can not be considered an old one. Nevertheless, the Russian 
botanist, Maximowicz (27), who worked on the plants of the un- 
tiring Tibetan explorer Prejevalsky, says that the flora is extremely 
ancient. 
As the Workmans and other travellers have remarked, Ladak 
and Baltistan are lands of rock ruin. In the summer the heat in 
the daytime is so intense and it is so cold at night that the moun- 
tains are cracked and crumbling and there are huge talus slopes 
at their feet. Even in the winter Moorcroft reports that the 
heat may be intense for an hour or two in the sun, making a 
great daily variation in temperature. 
CLIMATE 
Ladak is ainnet cloudless in the summer time and the glare 
from the bare rocks and the sand is so intense that travellers 
must wear smoked glasses and pith helmets and must take especial 
care to protect the skin. Sun temperatures are so high that it 
is a wonder that any plant can live out in the deserts. India is 
