744 



FLORA OF THE PERMIAN EPOCH. 



detained till the lower portion was firmly embedded in the rapidly 

 forming sandstone. The embedding of stems in strata of sandstone 

 is similar to what Gardner saw near the mouth of the Eio San Fran- 

 cisco, where coco-nut trees were found with their stems immersed to 

 the depth of 50 feet or more in the embankment of sand which 

 stretches along the shore. Phillips remarks, that the condition of 





'i,Jts i^v 



11 ' 



r 



i. 



v 1 -i- 



Fig. 922. 



the plants which compose the coal, the general absence of roots, the 

 fragmentary state of the stems and branches, the dispersed condition 

 of the separable organs, all confirm the conclusion that the plants 

 have been swept down from the land on which they grew by watery 

 currents, often repeated, and deposited in basins and large estuaries 

 of the sea, or, perhaps rarely, in lakes of fresh water. 



Flora op the Permian Epoch. — The nature of the 

 vegetation during the Permian period, which is associated with 

 the Carboniferous, under the reign of Acrogens, has not been 

 positively determined. Brongniart has enumerated the fossils in 

 three different localities, which he refers doubtfully to this period. 

 1. The flora of the bituminous slates of Thuringia, composed 

 of Algae, Ferns, and Coniferse. 2. Flora of the Permian sandstones of 

 Russia, comprehending Ferns, Equisetacese, Lycopodiacese, and Nog- 

 gerathiae. 3. Flora of the slaty schists of Lod^ve, composed of Ferns, 



Hg. 922. Vertical stems of fossil trees, Calamites chiefly, found in the Coal-measnres of 

 Treuil, near Saint Etienne. 



