THE WEAEDEN FORMATION. 263 



in a period of unfathomable antiquity and of long- 

 duration. The innumerable relics of marine or- 

 ganisms showed that then, as now, the sea was 

 teeming with life ; while a few vestiges of ter- 

 restrial plants and animals attested the existence 

 of dry land, inhabited by oviparous quadrupeds 

 and clothed with vegetation, during the formation 

 of this series of oceanic deposits. 



The natural records of an antecedent epoch are 

 now before us, and we proceed to examine an 

 assemblage of strata, not of marine, but of fresh- 

 water origin, that was deposited ere the formation 

 of the cretaceous rocks commenced ; for these 

 fluviatile sediments constituted the sea-bottom, 

 over which was spread the first layer of the green- 

 sand (see p. 221). From the extension of these 

 deposits over the wealds of the south-east of 

 England, and from their fluviatile characters having 

 in the first instance been determined by observa- 

 tions on the strata and organic remains discovered 

 in those districts, the formation has received the 

 name of The Wealden. 



Before entering upon the examination of the 

 cliffs in Brook Bay, which will form the principal 

 object of the present excursion, a few general ob- 

 servations on river deposits, and on the information 

 to be derived from their investigation, as to the 



