PRESTWICH — WOOLWICH AND READING SERIES. 97 



Well-section, Ewhurst. 



Woolwich 



Feet. 



fy^. Red and blue mottled clay 20 



Blue clay with pebbles 15 



^ T) /I- J ^- Black clay with small oysters 15 



Series, 



A bright ore (iron pyrites) 3 



Coal {lignite) 7 > 



Green sand and gravel {flints) 2 



62 

 Chalk 17 



At Chinham, near Basingstoke, mottled clays prevail, as they do 

 also at Old Basing, where they are 50 to 60 feet thick, with only one 

 bed of yellow sand about 5 feet thick above and 2 feet of sand below 

 them. It is uncertain whether about 20 feet of fossiliferous brown 

 clay, overlying the sand and mottled clays, should not he included in 

 this division, but the railway section, when I saw it, was too imperfect 

 to admit of a satisfactory examination. A further investigation of 

 the organic remains at this locality would be desirable. 



At Odiham and Farnham these beds present but little variety, 

 consisting almost entirely of mottled clays about 30 feet thick. 

 The following is the section of a well at Dogmersfield Park near 

 Odiham : — 



Well-section, Dogmersfield Park. 



(A. Bond.) 



Feet. 



^ "'\a. Fine Ught bluish sand 25 



London Clay Blue clay with septaria 330 



I. Basement-bed of \b. Sand, quite green \\ 



the London Clayey a. Stone {septaria) 2|- 



Cg. Sand, quite green 1^ 



11. Woolwich and J •^- ^j^^' yellow, niottled red with some grey ... 5 



Readina Series. "^ ^- Clayey sand, bluish grey striped red 10 



^ ' \ d. Chocolate-coloured ciay mottled with grey... 11^ 



i^ c. Mottled light grey and red clay 15 



417 



East of Farnham the band of Ost?'ea Bellovacina is found on the 

 chalk. At Guildford we meet with the first traces of the Woolwich 

 shell beds. They form on the top of the mottled clays a thin stratum 

 with an eroded surface, on which reposes the " Basement-bed of the 

 London Clay" (see Section in Journ. Geol. Soc. vol. vi. p. 2G0, and 

 PI. I. Diag. B, Loc. sect. 6 in this volume). 



At Fetcham the sand bed immediately overlying the chalk is said 

 to be 35 feet thick*, and to be underlaid by a band of the Ostrea Bel- 

 lovacina. On the chalk hills south of Leatherhead are several out- 

 liers of the " Lower London Tertiaries " consisting chiefly of sands 

 and pebble beds. The most important one is at Headley-on-tbe-hill, 



* In open sections I have never seen it above 10 to 12 feet thick. 

 VOL. X. PART I. H 



