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JUNE, 1921)
TRANS-HIMALAYAN REMINISCENCES IN PALI LITERATURE
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pasture lands of Central Asia, perhaps with occasional settlements in some well-watered and sheltered valleys. A look at the map of Asia showing the vegetation zones makes it clear that even after making allowance for the great changes which have taken place in the climatic conditions of Central and Northern Asia since the times of which we are talking, it is safe to assert that these pasture lands must have been situated in the central mountain area and the de pressions around them, with sufficient water to form rich grass lands. North Siberia is a frozen waste. South of it, there are temperate forests bordered by small patches of cultivation, and further down, vast expanses of very poor soil, perhaps fit only for growing grass, and barren wastes in the form of deserts, though not unrelieved now.and then by oases formed by rivers with an inland flow. In Southern and Eastern Asia, bordering the sea, there are rich cultivable lands which have formed the cradles of Asiatic civilisation. In geological times a good deal of the waste land of Central Asia was covered by seas, which made the climate mild enough for sustaining vegetable and animal life of a higher order. West of the central mountain mass, a great sea connected the isolated inland waters with the Mediterranean on the one hand and the Arctic Sea on the other, and has left indelible traces of its existence in the configuration of the land as well as in the fossil remains which it has left em bedded in the soil. In the same way, to the east of the central meridional mountains, in the Tarin basin and the depression represented by the desert of Gobi, it is believed that a great sea covered the land, though there are geologists who hold that the desert has been formed entirely by ærial denudation, i.e., by the wind-blown rock-debris from the marginal mountain chains. It has been asserted by competent authorities that during the glacial and the post-glacial periods the vegetation of Turkestan and of Central Asia was quite different from what it is now and was similar to the conditions which at present prevail in Siberia or North Europe. The extremely rapid desiccation of Central Asia has brought about great changes in the fauna and flora of the Thienshan and other central Asiatic regions. All these considerations point to the fact that in the nomadic stage, the Aryans, at least the Indo-Iranic branch of the Aryans, moved about the pasture lands of Central Asia with occasional settlements in the sparsely-scattered sheltered valleys or in the oases formed by the rivers, which carried the drainage of the central mountain mass into inland seas or lost themselves in the sands of the deserts into which they flowed.
The theory of a more northern habitation for the earlier Aryans does not in any way do violence to geological evidence. In the interglacial period, the northern parts of the hemisphere we live in are supposed to have been more equable and milder than at present, the mean temperature being higher and there being a greater precipitation of moisture. As a consequence of this, vegetation flourished far north where it can now hardly exist. Sir Archibald Geikie sayg46 that "the frozen tundras of Siberia appear then (in the interglacial period) to have supported forests which have long since been extirpated, the present northern limit of trees lying far to the southward." Among the fauna of this period are to be found the huge pachyderms, such as the Mammoth and the Rhinoceros, which roamed in the forests and over the grassy plains of the old world. When the glacial deluge came again, they seem to have survived the extreme cold and to have gone back to their old haunts after the climate had become less severe, if it is a significant fact of Palæontology that signs of the existence of man in the shape of the rude stone implements which he used at a remote age are found along with the skeletonal remains of these animals.
46 Text Book of Geology, Vol. II, p. 1316.
