THE PETRIFIED FOREST. 397 



trees had been snapped, or wrenched off, at a 

 short distance from the ground. Some were two 

 feet in diameter, and the united fragments of one 

 of the prostrate trunks, indicated a total length 

 of between thirty and forty feet. In many ex- 

 amples portions of branches remained attached to 

 the steins. The external surface of all the trees 

 I examined was weatherworn, and resembled that 

 of posts and timbers of groins and piers within the 

 reach of the tides, and subjected to the alternate 

 influence of the water and the atmosphere. There 

 were no vestiges of the bark in a carbonized state, 

 nor of the natural external surface of the steins, 

 as in the prostrate trees at Brook Point in the 

 Isle of Wight (see p. 281.)* 



The cycadeous plants occur in the intervals 

 between the trees, and the dirt-bed is so little con- 

 solidated, that I dug up with a spade several spe- 

 cimens that were standing erect, in the position in 

 which they originally grew. These plants, though 

 related to the Cycadeae (p. 290), are referred by 

 M. Adolphe Brongniart to a new genus, which he 



* In the Botanic Gardens in the Regent's Park, there are several magni- 

 ficent specimens of the Portland trees, with the trunks remaining upright in 

 the mounds of stone, and the silicified roots extending into the bituminous 

 rubble of the dirt-bed. They are placed near the foot of the artificial mount 

 in the pleasure grounds. A great part of the stone-work of the cascade in 

 the Colosseum in the Regent's Park, is constructed of fragments of the fossil 

 wood of Portland. 



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