§ 1. I n a former communication* I gave an account of some features of the Pleistocene deposits along the coast of Aberdeenshire, showing that in certain localities remains of marine animals occur of a character similar to those met with in the later tertiary beds of the Clyde district, and, like them, indicating the presence of a colder sea. The following pages are devoted chiefly to the Drift of the interior of the country and of the higher grounds, more especially as regards that part of Scotland lying between the Moray Firth and the Firth of Tay. In the lower parts of this district we find the drift-beds and brick-clays covered by a widespread accumulation of water-rolled gravel, often of great thickness and destitute of fossils. It is poured out in greatest profusion towards the mouths of valleys, and pervades all the river-basins I have examined, decreasing in extent as we ascend their course. It is not, however, confined to the neighbourhood of those streams, but also covers many tracts where no river appears to have existed. All along the valley of the Dee, from the seaport of Aberdeen to Braemar, which is situated nearly sixty miles into the interior, this upper rolled gravel is everywhere to be found diminishing, however, greatly in quantity towards the head of the valley. At Aberdeen it forms large swelling mounds and little hills, on which a great part of the city and its suburbs is buit. In many places it is spread out