A Glance at the map stows that within a short distance of the town of Nottingham there are Coal-measures, Permian, Bunter, keuper, and Lias rocks. A paper therefore on the district must of necessity be somewhat lengthy, but perhaps of all the greater interest as dealing with the border-land of the Palæozoic and Mesozoic epochs. The generally supposed unconformability between the Permian and Triassic rocks does not appear to exist in this area; while that between the Permian and the Coal-measures is very considerable.