hurricanes averaged 58 per cent more numerous with sunspot numbers above forty than with numbers below forty, while from July to September the difference amounted to 23 per cent. Even at this season some snow falls on the higher slopes, while the increased cloudiness due to numerous storms also tends to preserve the snow. Thus a great increase in the frequency of sunspots is accompanied by increased intensity of tropical hurricanes, especially in the cooler autumn and spring months, and results not only in a greater accumulation of snow but in a decrease in the melting of the snow because of more abundant clouds. At such times as the Permian, the general low temperature due to rapid convection and to the scarcity of carbon dioxide presumably joined with the extension of the lands in producing great high-pressure areas over the lands in middle latitudes during the winters, and thus caused the more northern, or mid-latitude type of cyclonic storms to be shifted to the equatorward side of the continents at that season. This would cause an increase of precipitation in winter as well as during the months when tropical hurricanes abound. Many other circumstances would cooeperate to produce a similar result. For example, the general low temperature would cause the sea to be covered with ice in lower latitudes than now, and would help to create high-pressure areas in middle latitudes, thus driving the storms far south. If the sea water were fresher than now, as it probably was to a notable extent in the Proterozoic and perhaps to some slight extent in the Permian, the higher freezing point would also further the extension of the ice and help to keep the storms away from high latitudes. If to this there is added a distribution of land and sea such that the volume of the warm ocean currents flowing from low to high latitudes was diminished, as appears to have been the case, there seems to be no difficulty in explaining the subtropical location of the main glaciation in both the Permian and the Proterozoic. An increase of storminess seems to be the key to the whole situation.