XCU PBOCEEDINGS OF THE GEOLOGICAL SOCIETY. 



characterize the Cretaceous flora of Europe have not been found at 

 JN^ebraska. 



If we compare the plants of the Nebraska with the Tertiary plants 

 we find no identical species, but seven genera {Populus, Salix, Ficus, 

 Platanus, Andromeda, Diospyrus, and Magnolia), which are both 

 Miocene and still living ; thus the flora of the Nebraska is more 

 closely connected with the Tertiary than with the Cretaceous flora of 

 Europe. "We must also remember that we are acquainted with only 

 a small number of the American species, and, on the other hand, 

 that the Cretaceous flora of Europe is more allied to the Tertiary flora 

 than was generally supposed. In the Cretaceous flora of Moletein 

 in Moravia are found Ficus and Magnolia, which resemble Tertiary 

 species ; one of the Myrtacece, resembling the Eucalyptus rhododen- 

 droides, Mass., of Monte Boloa ; a Juglayis, and a Laurinea, analogous 

 to those of the Tertiary flora ; a Pinus, and two other Coniferce 

 belonging to the genus Sequoia, very abundant in Europe and 

 America during the Miocene period, and which is now found only 

 in California. 



As the Cretaceous fishes more closely resemble the Tertiary than 

 the Jurassic fishes, the Upper Cretaceous flora is also quite distinct 

 from the Jurassic, and is more allied to the Tertiary flora ; and it 

 appears that in America there is a closer connexion between the 

 Tertiary and the Cretaceous floras than in Europe. 



It is very remarkable that the plants of the Nebraska bear so 

 much resemblance to the living flora of America, whilst the Cretaceous 

 flora of Europe has rather an Indo- Australian character. Thus it 

 appears that since the Chalk period the flora of America has not un- 

 dergone so great a change as the flora of Europe ; and whilst the 

 Cretaceous flora of Europe is altogether different from the living 

 European flora, that of Nebraska contains eight genera which are 

 still living in America ; and it is remarkable that the greater part of 

 them are still found in the same latitude. 



I flnd in one of the last numbers of the ' Proceedings of the 

 American Philosophical Society, held at Philadelphia' *, an interest- 

 ing account by Mr. Lesley of a recent discovery of Lignite in iron- 

 ore at Pond Bank, in Eranldin County, Pennsylvania, and in which 

 he describes the importance of the discovery in a theoretical point of 

 view. Only one similar discovery had before been made, namely, in 

 Yermont, and, as Mr. Lesley observes, they reopen the discussion of 

 the age of the present Silurian, Devonian, and Carboniferous surfaces, 

 and suggest an entire revolution in the generally accepted modes 

 of regarding the production of Appalachian topography. The Lignite 

 was struck in a shaft 40 feet below the surface ; it contains large 

 logs of wood, which is partly converted into a brilliant cannel coal, 

 and the rest of it into common brown coal. Its extent is by no 

 means considerable ; and Mr. Lesley, dissenting from the views of 

 Professor Hitchcock, describes it as a mere plug of coal thrust ver- 

 tically downwards into a mass of clay. It is closely associated with 



* Vol. ix. p. 463. 



