680 NOTES TO BOOK XVIII. 



have not failed to contribute their share to the latest 

 advances in the science. The following order of strata 

 proceeding upwards is now, I think, recognized throughout 

 Europe. The Silurian ; the Devonian, (Old Red Sand- 

 stone ;) the Carboniferous ; the Permian, (Lower part of 

 the new Red Sandstone series ;) the Trias, (Upper three 

 members of the New Red Sandstone series ;) the Lias ; 

 the Oolite, (in which are reckoned by M. D'Orbigny the 

 Etages Bathonien, Oxonien, Kimmeridgien, and Portlan- 

 dien ;) the Neocomien, (Lower Green Sand,) the Chalk ; 

 and above these, Tertiary and Supra-Tertiary beds. Of 

 these, the Silurian, described by Sir R. Murchison from 

 its types in South Wales, has been traced by European 

 Geologists through the Ardennes. Servia, Turkey, the 

 shores of the gulf of Finland, the valley of the Missi- 

 sippi, the west coast of North America, and the moun- 

 tains of South America. Again, the labours of Prof. 

 Sedgwick and Sir R. Murchison, in 1836, 7, and 8, aided 

 by the sagacity of Mr. Lonsdale, led to their placing cer- 

 tain rocks of Devon and Cornwall as a formation interme- 

 diate between the Silurian and Carboniferous Series ; and 

 the Devonian System thus established has been accepted 

 by Geologists in general, and has been traced, not only in 

 various parts of Europe, but in Australia and Tasmania, 

 and in the neighbourhood of the Alleghanies. 



Above the Carboniferous Series, Sir R. Murchison and 

 his fellow-labourers, M. de Verneuil and Count Keyser- 

 ling, have found in Russia a well-developed series of rocks 

 occupying the ancient kingdom of Permia, which they have 

 hence called the Permian formation ; and this term also 

 has found general acceptance. The next group, the 

 Keuper, Muschelkalk, and Bunter Sandstein of Germany. 



