68 PROCEEDINGS COTTESWOLD CLUB 1901 
down to the same level as the Carboniferous Limestone 
in which it occurs, and having been bored by the same 
animals anterior to the deposit of Inferior Oolite. Still 
further affording the observer relative dates for these per- 
forations, he will find that the beds of Inferior Oolite itself 
are thus bored, and by the same kind of animals, as can 
be seen in the quarries at Doulting, on the south of the 
Mendips, and near Ammersdown, on the north.” After 
this denudation the Mendips again slowly sank, and the 
late “Inferior Oolite” sea crept over the denuded 
Mesozoic Rocks, and on to the Paleozoic Rocks, and 
thus in the well-known section at Vallis, the CZypeus-grit 
rests upon the Carboniferous Limestone. In other parts, 
it rests upon Old Red Sandstone, Lower Limestone 
Shales, Carboniferous Limestone, Millstone-grit ; and, 
near Mells on the Coal Measures and ‘“ Dolomitic Con- 
glomerate.” Where the upper beds of “ Inferior Oolite” 
rest upon the Carboniferous Limestone, the surface of 
the latter is remarkably even.* In places, as on the top 
of the hill between Holwell and Leighton, oyster shells 
are found adhering to its denuded surface. 
There is no definite evidence of the final submergence 
of the Mendips in the form of Lower Oolitic dykes, such 
as exists in the case of the Liassic beds at Guerney Slade. 
Prof. Lloyd Morgan? has pointed out that the Oxford 
Clay is a formation of wide extent, as well as of com- 
parative uniformity in thickness and character, so that no 
doubt it was deposited in deeper water than the Oolitic 
limestones that had preceded it. Since the “Inferior 
Oolite” and the Fuller’s Earth at Whatley tell us that 
the sea had crept far up the flanks of Mendip, he con- 
siders it probable that Mendip and Blackdown were 
1 “Geological Observer,” (1853), p. 486. 
2 “The Mendips: A Geological Reverie,” p. 255. 
