270 GEOLOGY OF THE ISLE OF WIGHT. 



(p. 215), from Dr. Fitton's Memoir; to which 

 reference must be made for details, which though 

 of great value in a scientific point of view, possess 

 but little interest for the general observer.* 

 The Wealden strata forming this line of coast, 

 consist of laminated clays, shales, and loosely 

 coherent sands, full of freshwater shells and crus- 

 taceans, with lignite, and in some strata abundance 

 of pyrites ; layers, a few inches in thickness, of 

 tough bluish argillaceous shelly limestones, some 

 being composed chiefly of bivalves, and others of 

 univalves ; sands, with concretionary nodules of 

 calcareous compact grit and sand-rock ; and varie- 

 gated clays, mottled with different shades of red, 

 yellow, blue, green, and grey; waterworn bones 

 of reptiles occur throughout. But the subdi- 

 visions of the Wealden are in a great measure 

 arbitrary, for the same fossils, and the same litho- 

 logical characters, pervade the entire series. 

 Beds of sands, clays, and argillaceous limestones, 

 and calciferous grits, almost identical in mineral 

 composition, and containing similar organic re- 

 mains, are found alike in the upper and lower 

 part of the series; indicating a similar condition 

 of the land and water throughout the Wealden 

 epoch. In that part of Sussex over which my 



<•> "I. Trans, vol. iv. second series, p. 197 — 220. 



