§ 19. ORGANIC REMAINS OF THE WEALDEN. 391 



1 9. Organic remains of the Wealden. — The fossils of 

 the Wealden consist of leaves, stems and branches of plants 

 of a tropical character ; bones of enormous terrestrial 

 reptiles of extinct genera, and of turtles, flying reptiles, and 

 birds ; remains of fishes of several genera and species ; and 

 numerous fluviatile shells and crustaceans. 



The bones are, for the most part, broken and rolled, as if 

 they had been transported from a distance. They are more 

 or less impregnated with iron, and commonly of a dark 

 brown colour. Those in loose sand and sandstone are often 

 porous and friable ; those in the Tilgate grit, heavy, brittle, 

 and with the internal structure well preserved ; in fractured 

 portions imbedded in the limestone, the interstices are filled 

 with white calcareous spar, and the cancellated structure of 

 the bones is frequently permeated by the same substance. 



The fossil vegetables occur either bitumenized, or in the 

 state of sandstone casts ; carbonized leaves and twigs are 

 abundant in some of the strata, and the stems and branches 

 are sometimes silicified. 



columnar and in amorphous masses, veins and dykes — every where 

 occurs, and craters of extinct volcanoes are still visible. Elevations 

 and dislocations of the strata have taken place on an immense scale ; 

 and successive beds of basalt, amygdaloidal trap, and breccia, prove 

 the alternation of igneous action and periods of repose. Within a few 

 miles of the cascades of the river Columbia, and extending upwards of 

 twenty miles, trees are seen standing in their natural position, in a 

 depth of water from twenty to thirty feet. The trees reach to high, or 

 fresh-water mark, which is fifteen feet above the lowest level of the 

 tide ; but they do not project beyond the freshet rise, above which 

 their tops are decayed and gone. In many places the trees are so 

 numerous, that " we had to pick our way with the canoe, as through a 

 forest. The water of the river was so clear, that the position of the 

 trees could be distinctly seen down to their spreading roots, and they 

 are standing as in their natural state, before the country had become 

 submerged. Their undisturbed position proves that the subsidence 

 must have taken place in a tranquil manner." — Journal of an Exploring 

 Tour beyond the Rocky Mountains-) by the Rev. Samuel Parker, A.M. 

 New York. 1838. 



