THE VEGETABLE WORLD. 281 



remains of species of Tangle, accompanied by sea animals, 

 of which solitary representatives were already exhibited in 

 the preceding Cambrian formation. The species of Tangle 

 met with, manifest a great general agreement with those 

 forms now occurring in the tropics. It must not, of 

 course, be forgotten, that the Grauwacke has as yet been 

 carefully examined almost solely in England and Germany, 

 and that in these very places its layers have been so 

 enormously disturbed and altered by the subsequently 

 upheaved rocks, and by the action of the glowing masses 

 of these, that certainly many of the remains enclosed 

 within them must have been destroyed in those revolutions. 

 In Russia, on the other hand, this formation appears to 

 occur to an extraordinary extent in undisturbed stratified 

 condition, lifted very slowly and quietly above the 

 surface of the sea ; and from these we shall, hereafter, 

 first obtain an accurate knowledge of these oldest marine 

 deposits. 



In the second period, numerous islands were formed, the 

 soil of which, consisting for the most part of layers of the 

 former period, supported a rich land vegetation. A part 

 of England and Scotland, the country of the Rhine, the 

 Erzgebirge and the Sudeten, central France, the Vosges, 

 northward, a part of Sweden and Norway, the Alleghanies 

 in North America, and some other points, may with 

 certainty be named as such groups of islands, upon which 

 was developed a vegetation quite tropical in its character, 

 but wholly strange in its individual forms, and consisting 

 in great part of races of plants which have now totally 

 disappeared from the earth. A few Palms and some 

 Cycadacese, some gigantic Equisetums or Horsetails, twelve 

 to twenty feet high, are found scattered in thick woods of 

 arborescent Ferns, which alternate with Lepidodendrons 

 (Club-mosses, rising up into mighty trunks), Sigillarias 



