For many years past the Swedish geologists have been directing the attention of the scientific world to the curious phenomenon of the occurrence of submerged forests in certain of their inland lakes. In our own country such evidences of change of level are a familiar sight along our sea-coasts, and, if we bear in mind the extreme instability of the sea-level, their presence is little to be wondered at. In all bodies of water which hare no outlet—and the sea is only the largest of these—the surface-level is determined by the balance between supply and evaporation, and oscillation is inevitable. In the case of freshwater lakes, however, the level is determined within small limits by the overflow, and the occurrence of tree stumps in the position of growth beneath their waters presents therefore a problem of considerable interest.