Summary: | The known palaeontological and stratigraphical evidence is used as a basis for the construction of maps of the continents showing the extent of their inundation by the sea in Sakmarian time in the Upper Palaeozoic. In the northern hemisphere apart from India the evidence is sufficiently reliable to give reasonable maps, and the great extent of the inundations suggests that the climate would be considerably modified from that of today; no undoubted Sakmarian glacials occur there. In Southern continents and India, the "Gondwana" biogeographical province has made correlation with the northern continents controversial, but reasons are given for assuming that "Gondwana" glacial deposits were at least in part Sakmarian; the resultant maps show that the "Gondwana" land surfaces were but little reduced in area, and that the main glacials (except for India) lie within a belt between 40{ring operator} S and 20{ring operator} S. Present lack of knowledge of Sakmarian conditions in Antarctica makes reconstructions of climatic belts too hazardous for possible use in enunciating or checking hypotheses of continental drift and polar wandering.
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