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question put to him, writes : " The Carboniferous series is so inconstant when very large 
areas are concerned, that no description of lithological succession applies to the whole. 
If you turn to p. 119 of the last edition of my 'Physical Geology and Geography of 
Great Britain ' (1878), you will see the order of succession for Wales and the Bristol 
and Mendip country, omitting the yellow sandstone with plants, Ireland, &c. In Derby- 
shire the Millstone-grit begins to get much interstratified with shales, and what Binney 
called the Ganister beds come on in Lancashire above the Millstone-srit. If the 
Ganister is in South Wales, Logan and DelaBeche did not recognise it. North of 
Derbyshire, part of Yorkshire, and in great part of Northumberland and Durham, the 
Millstone-grit gets more and more mingled with shales, and in Northumberland and its 
borders the Carboniferous Limestone also gets so largely interstratified with shales and 
sandstones that the limestone, as such, is but moderately developed, while in Cumber- 
land and Westmoreland the limestone is very massive and thick, as a whole. There are 
beds of coal in the Carboniferous Limestone series in Northumberland, and in Scotland, 
in Edinburghshire ; about Dalkeith half the coals of that coalfield are below the Millstone- 
grit and limestones, for there are several thin beds of limestone." 
At p. 119 of his ' Manual of Geology ' Prof. Ramsay says : " In the south and middle 
of England, the Carboniferous rocks consist chiefly of limestone at the base, and Coal- 
measures above. Including the South of Wales, the Eorest of Dean, the Somersetshire 
and other areas, a typical section of the beds is as follows : 
Feet. Feet. 
Coal-measures . 
1000 to 12,000 
Millstone-grit .... 
500 „ 1,000 
Yoredale rocks. 
100 „ 1,000 
Carboniferous or Mountain limestone 
500 „ 2,500 
Carboniferous limestone- shales 
100 „ 500 
Yellow sandstone with plants, Ireland, &c. 
100 „ 200 
Generally resting on Old Red Sandstone." 
He adds, " The yelloio sandstone bed often forms a passage from the Old Red Sandstone 
to the Carboniferous rocks, and the plants have Carboniferous affinities. The accom- 
panying sliales in Pembrokeshire and elsewhere contain numerous fish teeth, Spirifers, 
Productus, and a few Lingulas and the Carboniferous TAmestone, which is more than 
2000 feet thick in South Wales and in Somersetshire, is so highly fossiliferous that it 
may be stated that the whole of the limestone once formed parts of animals. The 
lowest 500 feet consists chiefly of fragments of Bncrinites. The Yoredale rocks of 
Yorkshire have no precise lithological parallel in South Wales and Somerset. They 
consist chiefly of shales and sandstone, Avith marine shells, and occasional land plants. 
The Millstone-grit of South Wales is comparatively unfossiliferous, but sometimes con- 
