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PROCEEDINGS COTTESWOLD CIJJB 
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Finally, there is a quarry just below Llandegveth Church. 
The yellow quartzose sandstone at the base of the Old Red 
Sandstone is seen below the Churchyard wall, and the top-most 
bed in the quarry is about 6 feet below that exposure. Here is 
seen one foot of brown sandstone, much ironstained, and below 
it, 9 feet of brown earthy sandstones and sandy shales. The 
base of the brown sandstone is crowded with Holopella gregaria. 
Though the Ludlow beds cannot be divided into sharply 
marked upper and lower divisions, one can say that the upper 
deposits are of the nature of sandstones and sandy shales, 
while the lower ones are sandstones with either thin calcareous 
layers or with bands of calcareous nodules. These deposits, 
however, are palaeontologically very similar except that Dayia 
navicula does not range into the topmost beds, and Holopella 
seems to be confined to the uppermost layers. 
III. (b). detailed account of the 
LLANGIBBY AREA. 
The Llangibby Anticline runs from near Llwyn-Celyn for 
about three miles northwards to Cwm Dowlais. There it meets 
a cross fault, beyond which nothing but Ludlow beds are seen, 
in which no anticlinal arrangement is to be found. 
On their Eastern side, the Silurian beds of the Llangibby 
Anticline dip to the South-East or South-South-East at very 
much the same angles as the neighbouring Old Red Sandstone 
beds, but that tlie junction between the two is a fault line is 
obvious from the following considerations : — 
(1) The top of the Wenlock Limestone at Cwm Dowlais 
is only about 300 yards from the Old Red Sandstone, and 
as the dip of the Ludlow beds is on the average 35°, their 
thickness must be about 500 feet. Since, in the Coed-y-paen 
Anticline, there are 1300 feet of Ludlow beds, much of these 
must be missing near Cwm Dowlais. 
(2) In a pit near the bottom of the valley, South of 
Llangibby Castle, Ludlow sandstones and shales very close 
to the Old Red Sandstone, are exposed, and are seen to be 
crumpled. 
