_The Permo-Carboniferous Rocks._ In the Salt Range of the North-West of India an interesting series of sandstones alternating with limestones rests unconformably upon lower rocks. The sandstones are known as the Speckled Sandstones, while the limestones are termed the _Productus_ Limestones. The Lower and Middle Speckled Sandstones are succeeded by the Lower _Productus_ Limestone which is separated from the Lower division of the Middle _Productus_ Limestone by the Upper Speckled Sandstone; these are all of the Permo-Carboniferous period, while the upper part of the Middle _Productus_ Limestone and the Upper _Productus_ Limestone belongs to the Permian period. The fossils, largely invertebrates, are intermediate in character between those of Carboniferous and Permian ages. Similar fossils are found in the marine Permo-Carboniferous beds of the other areas which have been named above. The Lower Speckled Sandstone is of interest on account of the occurrence of boulder-beds within it, and this division of the sandstone has been correlated with the lowest (Talchir) stage of the Permo-Carboniferous strata of other parts of India, while the other Speckled Sandstones and those divisions of _Productus_ Limestone which are referred to the Permo-Carboniferous are correlated with the higher divisions of other parts. Special mention is made of the Talchir division, on account of the occurrence therein of boulder beds which have long been known, and whose glacial origin was inferred by Dr W. T. Blanford forty years ago. The accumulations shew signs of having been deposited in water, but the existence of large subangular, sometimes striated boulders therein, which must have come from distant sources, and the occasional occurrence of striated rock surfaces on the strata upon which the Talchir beds repose unconformably points to ice-action; this would not be so very remarkable if it were an isolated case, though sufficiently so, from the comparative nearness of the region to the equator; but researches conducted in different parts of the southern hemisphere have brought to light similar, and sometimes even more striking evidences of glacial action in widely distinct regions[93]. In Australia they have been found in New South Wales, Victoria, South Australia, East Australia and Tasmania; the Dwyka boulder-conglomerates of South Africa and certain deposits of similar character discovered by Prof. Derby in Southern Brazil have been referred to the same period, and their glacial origin has also been inferred. This widespread distribution of deposits which are generally contemporaneous, of which the glacial origin may now be taken as established, is extremely remarkable, and must be taken into careful consideration by those who put forward theories framed to account for former climatic changes.