2i6 Lower Greensand. 



of the formation, on the north side of the Weald 

 at Maidstone. It rests on the Atherfield Clay. The 

 general grouping of the fossils in all this area corre- 

 sponds with that of the Isle of Wight. In Dorsetshire 

 and part of Somersetshire, at the south end of the 

 western escarpments of the Cretaceous rocks, the Lower 

 Grreensand is absent, and the Upper Grreensand rests 

 directly on the Lias and New Eed series. Further 

 north, the Lower Grreensand reappears in Wiltshire, 

 near Chapmanslade, about three miles east of Frome, 

 and in a long narrow band follows the direction of the 

 escarpment of Chalk, as far as the neighbourhood of 

 Devizes, where it widens for a space, and runs north 

 in a projecting tongue as far as Farringdon, where it is 

 known as the Sponge gravel. 



Beyond the Farringdon area, it is for a space of 

 twelve miles overlapped unconformably by the Grault, 

 to reappear a little south of Abingdon in a broad patch, 

 that extends eastward about six miles to Chiselhampton, 

 where it is again overlapped by the Grault, to reappear 

 in a narrow strip between Great Hazeley and the 

 neighbourhood of Thame. Several small outliers of 

 Lower Grreensand lie on the Purbeck strata, south, west, 

 and north of Aylesbury. At Leigh ton Buzzard it 

 appears in great force, covering all the country for 

 miles round Woburn, from whence it trends away to the 

 north-east, and disappears under the alluvium of the 

 Fens of Cambridgeshire, and runs along the east side of 

 the Wash, where, crossing under sea, it reappears in 

 Lincolnshire, and following the line of the chalk 

 escarpment runs in a NNW. line to the Humber. As a 

 whole this formation may be described as consisting of 

 yellow, grey, white, and green sands. 



In the Weald country and on the north-west 



