The geology of the neighbourhoods of Flint, Mold, and Ruthin ...

—
38 CARBONIFEBOTJS BOCKS.
they are therefore frequently referred to in the text and in the
fossil-lists in this Memoir. The following list gives the names
employed by Mr. Morton, alongside of those which had come into
use by the Geological Survey :
Geological Survey- Mr. Morton.
Millstone G-rit -. - , -, .. .. r -. Cefn-y-Fedw Sandstone,
r The Black Limestone (North Flintshire) The Upper Black Limestone.
i The calcareous sandstone series (South
L Flintshire) - - -
- Arenaceous Limestone.
s
The grey and white limestone - XS^^SSKi.
The lower brown limestone - - The Lower Brown Limestone.
(1 ) The lower brown limestone.
We may conveniently commence the description of the
Carboniferous Limestone by tracing this subdivision from north
to south, and noticing the exposures of its junction with the
Wenlock Shale below.
North of Caerwys the base lies hid for a long distance under
Drift, but in the ravine of Coed Maes-mynan, near that village,
comes into full view. The limestone dips a little east of north at
17°, the Wenlock Shale in the opposite direction at 31°, the two
lying therefore nearly at right angles. The limestone is thinbedded
and impure, several argillaceous bands possessing a
peculiar porcellanous texture and conchoidal fracture. The
section follows :
—
Old quarry in the lower beds
....
of the limestone, Coed Maes-mynan.
Feet. Inches.
Black shaly limestone 2
Dark porcellanous limestone . . .
6
do. rubbly
9
4
1
9
10
Do. ,
,
Very hard black limestone with a hackley fracture
Sandy shale - - • - •
Very hard black limestone with a hackley fracture
Dp. . do. earthy . .
Do. do. decomposed into a soft yellow
sand or loam - - - -
Green and yellow shale with a sandy band -
Hard black hackley limestone * '">-
>
Porcellanous limestone
....
• - -
Hard black hackley limestone
Porcellanous limestone ...
Yellow sandstone
...
Hard black limestone, weathering to yellow sand
Porcellanous limestone
Hard black limestone, shaly below ^
Porcellanous limestone
Hard black limestone, sandstone, and green shale
Porcellanous limestone -
3
6
9
2
3
6
3
1
0+
19 2