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south-west. In Liddesdale, therefore, the lower and upper cement- 
stone groups form one continuous series, with no intervening 
zones of marine limestone. The open sea must have stretched 
towards the south and west, while the land lay to the north, 
traces of its margin being still recognisable about the flank of 
Carter Fell. 
8. The Canohie Coal group comprises a series of strata about 800 
feet thick, containing thirteen coal-seams, which include an aggregate 
thickness of 39 feet of coal. The lower seams are intercalated with 
marine limestones, so that their low position in the Carboniferous 
series admits of no doubt. It is remarkable, however, that the 
plants associated with these coals are true Coal-measure forms, as 
determined by Mr. B. Kidston. The Canohie group is overlaid by 
reddened sandstones lying below the Permian (St. Bees) sandstones, 
which cover them unconform ably. It is therefore impossible to 
follow the upward section further in the Esk valley. In Liddesdale, 
however, the Canohie coals may be traced running towards the north- 
east, and becoming much attenuated in their progress. They dip 
below the upper cement-stone group No. 9. 
9. Over the horizon of the Canohie coals in Liddesdale comes a 
group of blue shales and cement-stones, with several thick bands of 
sandstone and seams of coal on different horizons. Those beds 
present this ordinary “ cement-stone ” facies of the upper division 
of the Scottish Calciferous sandstones. 
10. The Plashetts and Lewisburn coal lie above the cement-stone 
group No. 9. 
11. The southern margin of Liddesdale is marked by a con- 
spicuous group of sandstone, of which the bottom beds cap the 
eminence of the Larriston Fells, and likewise rise into Peel Fell. 
The name of “ Fell Sandstones ” has been given to them. They 
must vary much in thickness, owing to the very lenticular character of 
their individual beds. In Liddesdale they may be 1000 feet thick. 
They cover a large area in Northumberland, and form a well-marked 
geological group lying immediately below the Main or Scar limestone, 
where the ordinary phase of the Carboniferous limestone reappears. 
It is evident that the central part of the thick cement-stone 
groups of Upper Liddesdale lies on the same horizon as the marine 
zone of Gilnockie below Langholm. There can be little doubt that 
the Scottish cement-stone series generally is a less thoroughly 
