The author described the circumstances which led him, in 1863, to begin the investigation of these terraces, and showed he had traced their course along the Earn from Loch Earn to where they meet the tide. He had also examined the valley of the Teith, and had found the same deposits from the head of Loch Lubnaig to near Stirling. There are three different levels on which the terraces lie at different heights above the river bed. The lowest consists of the present banks of the stream and haughs or meadows; above this there is an intermediate terrace, which, in its turn, is surmounted by the highest. Owing to the effects of denudation, one or other of these levels is frequently interrupted or obstructed, but they are ever again found recurring, and the whole three present themselves so frequently as to show that this threefold terrace system is the true key to these valley deposits.