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MISSISSIPPIAN PERIOD 



Fig. 374. Map showing the areas, in black, where the Mississippian system 

 appears at surface. The map also shows where the Mississippian system is thought 

 to exist, though buried (the lined areas), and the area from which it is thought to 

 have been removed by erosion (the dotted areas). By inference, also, the map shows 

 the relations of land and water during the Mississippian period. 



