Vol. 51.] GREENSAND OF EAST SURREY. 105 



The sections about Abinger are described in my paper already 

 referred to. The cherty sandstones and sands seen at Raikes Lane, 

 Iiaikes Hollow, Abinger Lane, Wotton Lane, Coast Hill, at the 

 surface near the tower on the top of Leith Hill, and at the upper 

 part of the pit above Abinger Bottom, belong to the upper division 

 of Local Group 2. In the last pit named the junction of the upper 

 and lower divisions is seen, and it is there clearly defined, but I do 

 not imply that that is always the case. In dividing the beds of Leith 

 Hill into an upper and lower group, I wish only to say that the 

 higher horizons consist of the rubbly beds of sandy chert, while 

 more massive beds come in below ; it is not at all clear to me that 

 the division is at a constant horizon. This question is almost hope- 

 lessly complicated by the peculiar effects of surface-weathering upon 

 chert : rubbly beds are always, so far as I have observed, seen near 

 the surface, and at least it cannot be proved that beds so situated in 

 the exposures on the east of Leith Hill, where lower horizons crop 

 out, are not the result of surface- action. I have referred to this 

 difficulty in a former paper x and shall have to do so again later on 

 here. There can be no doubt, however, that the rubbly beds are 

 distinctive of the higher horizons in all the sections just mentioned. 



Characteristic sections of the lower division of Local Group 2 may 

 be seen, besides at Abinger Bottom, at the pit near Coney Wood 

 opposite Woodhouse Farm, at the old quarry above Coldharbour, 

 and at Boar Hill. There are other sections in both divisions, but 

 those noticed here are the important ones. The beds of massive 

 greensand of the lower division appear to be spicular in a high 

 degree, which probably accounts for their hardness. Casts of 

 spicules, and I think spicules also, may even be seen in freshly- 

 broken specimens, whilst old weathered specimens from Coldharbour 

 yield most beautiful examples of the sponge-origin of these beds. 

 Drew mentions the purple-coloured beds in this quarry 2 ; these 

 appear to consist almost entirely of sponge-remains (the colour, I 

 think, is due to peaty stain). 



The beds of Local Group 4, ironsand often very like the Folke- 

 stone Sands, may be seen on the east of Leith Hill at the 700-foot 

 contour in Bedlands Wood, on the ascent from Holmwood Common 

 by way of Folly Lane. The best exposure is, however, under the 

 tower at the highest point of the hill. At least 100 feet of sand is 

 seen here, and I estimate the total thickness of these beds at between 

 100 and 130 feet, but it is difficult to speak with any certainty, on 

 account of the slips. The sands are compacted into soft sandstone on 

 certain horizons. 



From 90 to 100 feet of cherty beds cap the sands at the top of 

 Leith Hill (under the tower). The thickness here given to the 

 lower chert-beds is arrived at by careful comparison of the levels at 

 the southern end of the hill. As much as 60 feet of the upper cherts 

 is seen at Coast Hill, the exposures about Abinger show rather less, 

 but the thickness here given to the Bargate Beds is seen about 

 Ahiugcr, and the junction of the last with the Folkestones is the 



1 Proc. Geol. Assoc, vol. xiii. (1893) p. 141. 



2 Mem. Geol. Surv. 'Geology of the Weald,' 1875, p. 121. 



