172 ON A SECTIO]S" AT WALTON COMMON EXPOSING LONDON CLAY ETC. 



remarked on the common occurrence of " pans " in permeable beds 

 near the surface. He thought the " mixed gravels " of the Author 

 resembled in construction those found around the edges of many of 

 the plateaux in the Bagshot district. 



Mr. Clement Eeid thought that contortion of beds, like that 

 described by the Author, occurs in districts where no ice-action has 

 taken place, and he suggested that they might be due to the move- 

 ment of a soil-cap like that of the Falkland Islands. 



Mr. MoNCKTON had carefully examined all the sections where 

 unconformity might be detected, and found himself quite unable to 

 arrive at any certain conclusion on the subject. He doubted 

 whether the variable clays described were entitled to be called 

 Eamsdell Clay, a name originally applied to beds in the Newbury 

 district. 



Dr. G. J. HiNDE was able to recognize among the pebbles from 

 the Plateau-gravel, flints with Hexactinellid Sponges from the 

 Chalk, and portions of hard sponge-beds from the Neocomian strata 

 to the southward at Godalming and Hindhead. 



Mr. J. Staekie Gaednek had seen the section in question, and 

 was strongly inclined to believe in an unconformity between the 

 London Clay and the Lower Bagshot. The former, he thought, was 

 marine, and the latter, in this particular section, freshwater and 

 fluviatile, and therefore deposited at a much later date. 



The Authoe agreed that the question of unconformability was a 

 very difficult one to decide. He simply argued for unconformability 

 on a small scale in this particular section. He thought that the fact 

 of the Wimbledon gravels containing northern rocks was a proof of 

 the diiference of their age from the Oatlands gravel. He insisted 

 on the difi'erence between the London Clay and the argillaceous beds 

 of the Bagshots. He did not insist on the identification of the clay 

 at Walton with the Ramsdell Clay. He was inclined to agree with 

 Mr. Clement Eeid that the contorting of the beds, in the particular 

 instance mentioned, was due either to a soil-cap or to moving 

 masses of snow, though there were difiiculties in accepting this 

 interpretation. 



