The lower Himalayas to the south of Sikkim, and the tarai, or plains, which extend from the south of these ranges as far as the northern borders of Purnea district.
The Himalayas not only form a double wall along the north of India, but at both their eastern and western extremities send out ranges to the south, which protect its north-eastern and northwestern frontiers.
Like other plateaus, the great plateau of the centre of Asia, stretching from the Himalayas to Bering Strait, 2 has on its surface a number of gentle eminences (angehaufte Gebirge of K.
A large semi-circular tract, comprising the valleys of the Gogra and the Gumti, has long been separated from the remainder of the great plain as the kingdom of Oudh; and though since 1877 it has been under the administrative charge of a lieutenantgovernor, it retains certain features of its former status as a chief-commissionership. The province includes the whole upper portion of the wide Gangetic basin, from the Himalayas and the Punjab plain to the Vindhyan plateau, and the lowlying ricefields of Behar.
The great range of the diurnal variation of barometric pressure during the afternoon hours, - which is the more striking, since at Rurki, Lahore, and other stations near the foot of the Western Himalayas this range is less than in the open plains.
As the period advanced, along the very line that had been occupied by the nummulitic sea (Tethys) the crust began to be folded up, giving rise to the Alps, Carpathians, Caucasus, Himalayas and other mountains, some of the early Tertiary marine formations being now found raised more than 16,000 ft.
The higher mountains have a special flora showing close agreement over wide intervals of space, as well as affinities with the mountain flora of the eastern Mediterranean, the Himalayas and IndoChina (cf.
In the western hemisphere they range along the Mexican highlands and the Andes far into the tropics, while in the Old World the genus, well represented in the Himalayas and the hills of China, exists likewise in the peninsula of Malacca, in the Indian Archipelago and Malaya to the Philippine Islands and Borneo.
The Himalayas in the north of the district attain a height between 7000 and 8000 ft., one peak reaching an elevation of 8565 ft.; the highest point of the Siwalik range is 3041 ft.
In point of age it is very much older than either the Himalayas to the S.