CHAPTER IX. 



THE WEALDEN FORMATION NATURE OF RIVER DEPOSITS WEALDEN 



STRATA OF THE ISLE OF WIGHT EXCURSION TO BROOK BAY — CLIFFS 



FROM COMPTON CHINE TO BROOK POINT BROOK POINT — PETRIFIED 



TREES — STRUCTURE OF THE FOSSIL WOOD. 



The Wealden formation. — The lacustrine and 

 fiuviatile origin of the strata spread over the 

 northern part of the Island, was clearly denoted 

 by the prevalence of land and freshwater shells, 

 and the remains of aquatic and terrestrial plants; 

 and by the presence of bones of mammalia re- 

 lated to the Tapir, Peccari, &c, but referable 

 to extinct species and genera ; while the marine 

 and estuary shells, and other exuviae, in the de- 

 posits on which the freshwater beds were super- 

 imposed, afforded conclusive evidence that these 

 strata were formed in the basin of a comparatively 

 shallow sea. 



The cretaceous system, which so long engaged 

 our attention, displayed, on the contrary, an as- 

 semblage of sedimentary deposits that had been 

 accumulated in the profound depths of the ocean, 



