454 HISTORY OF GEOLOGY AND PALAEONTOLOGY. 



correctly the geological age of the Magnesian limestone and 

 the Red Conglomerates of Devonshire with the Thuringian 

 Zechstein group and the Red Underlyer series respectively. 



Freiesleben, in 1807, gave an excellent systematic description 

 of all the sedimentary rocks of Thuringia between the Red 

 Underlyer and the Muschelkalk, comprising the whole 

 succession under the name of Kupferschiefer Gebirge (Copper 

 Slate Series). D'Omalius d'Halloy in 1808 termed the same 

 complex Terrain Peneen, intending to give expression to the 

 paucity of fossils in the rocks. Afterwards, in the second 

 edition of his Elemente der Geologic (1834), D'Omalius d'Halloy 

 confined the term " Terrain Peneen " to the Red Underlyer, 

 Copper Slates, and Zechstein groups, and transferred the 

 Bunter Sandstones with the Muschelkalk and Keuper series to 

 the Trias, a designation for these three younger formations 

 which had been introduced by Alberti. 



In 1841, Murchison revealed the fact that a diverse 

 lithological series of rocks, identical in age with the Red 

 Underlyer and Zechstein, covered vast areas in the province of 

 Perm and in the Eastern region of European Russia, and said 

 Russia must be regarded as the typical district for these 

 formations. He therefore proposed to give to the formations 

 in question the name of Permian System, and classified the 

 system as the youngest member of the Palaeozoic succession. 

 This name rapidly displaced D'Halloy's designation of Terrain 

 Pene'en, all the more as Geinitz and Gutbier, in their admirable 

 monograph (1848-49) on the fossils of the German Zechstein 

 and Red Underlyer, strongly recommended the name of 

 c< Permian System ." On*the other hand, Marcou objected to the 

 name proposed by Murchison, on the plea that many of the 

 geological sections of the Russian area were inaccurate, and 

 that the rocks which Murchison had there ascribed to the 

 Permian system were frequently of Lower Triassic age. 



Jules Marcou recognised in 1853, for the first time, the 

 Permian age of a series of dolomitic limestones, marls, shales, 

 and conglomerates covering a large territory between the 

 Mississippi and the Rio Colorado. The presence of the same 

 complex was afterwards determined by Shumard (1858) in 

 New Mexico; by Meek, Swallow, and Hawn in Kansas; by 

 Worthen in Illinois, Missouri, and Nebraska ; by Cope and 

 White in Texas. Marcou observed two well-marked divisions 

 in the American series just as in the European, and he 



