146 GEOLOGY OF THE ISLE OF WIGHT. 



Low water numerous fossil shells washed up by 

 the sea are often to he met with. 



On the north side of Gurnet Bay, about two 

 miles to the west of Cowes, the cliffs are com- 

 posed of alternating beds of clay and limestone, 

 the latter abounding in freshwater shells (espe- 

 cially in potamides, PL II. figs. 2, 8, 9) and gijro- 

 gonites. In Thorney (or Thorness) Bay, similar 

 strata are exposed, with layers of blue clay and 

 sand, containing marine shells.* In several loca- 

 lities along the northern shores of the Island, as. 

 for instance, between Ryde and Cowes, and near 

 Cowes, fluvio-marine clays appear on the sides of 

 the sloping banks; but the exact stratigraphies] 

 position of these beds is concealed by vegetation ; 

 they are probably the equivalents of the strata in 

 the northern end of Whitecliff Bay, that contain 

 an intermixture of marine and fluviatile shells. 



Beyond Newtown Bay, arc Hampstead (Mill's 

 (about three miles east of Yarmouth), consisting 

 of calcareous marls, with the usual fluviatile shells, 

 in great abundance. In this locality, leaves of 

 dicotyledonous plants,-}- occasionally occur ; and 

 Mr. Prestwich has recently discovered great nuin- 



i states thai the entire buckler with the bono of a tortoisi 

 obtained from Thorness Hay. Geol. Trans, vol. ii. i>. 290. 



i] u i" those found in the plastic clay at Newhaven, in Sussex, and 

 i Isof th( South Downs, ' /'/. I. 



