170 GEOLOGY OF THE ISLE OF WIGHT. 



which are exhibited in the beautiful section of 

 Barton and Hordwell Cliffs, and of their peculiar 

 fossils, one may follow in imagination the gradual 

 silting up of an estuary, and its passage east- 

 ward into a pure river deposit. Leaving the 

 regular beds of London clay, which dip gradually 

 to the eastward, and are lost in the beach below 

 Beacon Bunny and Long-mead End, we meet with 

 a stratum of sand in which marine and freshwater 

 shells are intermixed, and one of clay containing 

 leaves and seeds, with an extensive layer of lig- 

 nite. Upon this is a bed whose organic contents 

 display a still nearer approach to freshwater origin 

 by the absence of the more decidedly marine 

 genera, as oliva, natica, &c, and the presence of 

 cyrena, potomomya, &c. in great abundance. Next 

 comes a layer of brown sand, containing rolled 

 fragments of bones of Palcvotherium , Trionyx, &c. y 

 which, from their appearance, may have been 

 transported from a considerable distance. Over 

 this rests a deposit of marl and white sand (No. 6 

 in Mr. Lyell's section), the latter in the state of 

 an impalpable powder; in this were deposited 

 nearly all the fossils above mentioned. The strata 

 incline to the east at an angle of about 5°. The 

 direction of the stream was no doubt westerly, 

 thai is, toward the marine beds; but at the spot 



