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1. The Permian System of Rocks. 2. Theory of the Origin of 

 Coal. 3. Lines of Ancient Sea Levels. 4. On Masto- 

 dontoid and Megatherioid Animals. 5. The Chief Aim of 

 the Geological Society of London. By R. I. Murchison, 

 Esq., President of the Geological Society, &c. &c.* 



1. Permian System of Bocks. — On its eastern frontier, far 

 removed from the tract to which allusion has been made, the 

 uppermost member of the carboniferous limestones of Nor- 

 thern and Central Russia, distinguished by the presence of 

 multitudes of the foraminifer Fusulina^ is succeeded by the 

 most widely spread of the Russian systems ; to which, from its 

 occupying the whole of the ancient kingdom of Permia, we 

 have assigned the name of Permian. You have been told, 

 that this vast group is composed of limestones, marls, great 

 masses of gypsum, rock-salt and repeated alternations of cup- 

 riferous strata ; and that it contains a flora and a fauna, of 

 characters intermediate between those of the Carboniferous 

 and Triassic periods. The shells are, to a great extent, those of 

 our Magnesian Limestone or Zechstein ; and, like the conglo- 

 merate of that deposit near Bristol, the Permian rocks are dis^ 

 tinguished by the presence of Thecodont Saurians. The in- 

 terest attached to these vast deposits, which have been spread 

 out on the western flanks of the Ural Mountains, is increased 

 by the inferences which have been drawn, that springs and 

 currents holding much copper in solution must have flowed 

 from the edges of that highly mineralized and metamorphic 

 chain, while the Permian strata were accumulating. But the 

 great value of having worked out a fuller and richer type of 

 a group of strata between the Carboniferous and Triassic 

 epochs than any which exists in Western Europe, will be found 

 in the fossil shells, the plates of which are already far advan- 

 ced ; for, with some species hitherto known in the Zechstein. 



• From the Address delivered at the Anniversary Meeting of the Geological 

 Society of London* 17th February 1843. 



