250 



LYELL'S ELEMENTS OF GEOLOGY. 



Fossil Plants of the Coal Strata. 



than those which we find in the fronds of different genera of 

 living ferns, which do not in the present state of the globe attain 

 the size of trees. 



Lepidodendra. — Another class of fossils, very common in 

 the coal -shales, have been named Lepidodendra. Some of these 

 are of small size, and approach very near in form to the modern 



Fig. 256. Fig. 257. Fig. 258. 



Lepidodendron Sternbergii. Coal-measures, near Newcastle. 



Fig. 256. Branching trunk, 49 feet long, supposed to have belonged to L. Stern- 

 bergii. (Foss. Flo. 203.) 

 Fig. 257. Branching stem with bark and leaves of X. Sternbergii. (Foss. Flo. 4.) 

 Fig. 258. Portion of same nearer the root ; natural size. (Ibid.) 



Lijcopodiums, or club-mosses, while others of much larger 

 dimensions are supposed to have been intermediate between these 

 and coniferous plants. The annexed figures represent a large 

 fossil, Lepidodendron, forty-nine feet long, lately found in Jar- 

 row Colliery, near Newcastle, lying in shale parallel to the 

 planes of stratification. Fragments of others, found in the same 

 shale, indicate by the size of the rhomboidal scars which cover 

 them a still greater magnitude. The living club-mosses, of 

 which there are about 200 species, are abundant in tropical cli- 

 mates, where one species is sometimes met with attaining a 

 height of three feet. They usually creep on the ground, but 

 some stand erect, as the L. densum, from New Zealand. (Fig. 

 259.) 



Calamites. — These fossils have a jointed stem, longitudinally 

 striated, and are supposed by M. Brongniart to have been allied 

 to the Equisetacece, or horse-tail tribe ; aquatic plants which, in 

 a living state, are only two or three feet high in our climates, 



