HUGHES : INGLEBOROUGH. 
189 
hill over which the Mountain Limestone rises in an anticlinal 
dome, partly due to original deposition along an elevated rounded 
ridge, and partly to the obstruction offered by the protruding 
mass during subsequent settling down and compression of the 
overlying rocks under the pressure of superincumbent strata. 
This, of course, affects the basement boundary line, which, 
therefore, bulge-s out to the N.W. Coincident with this change 
of conditions on the sea bottom, we find here a large number of 
fossils at the base of the limestone, and even among the stones of 
the basement conglomeratic breccia. We first notice that the 
fragments of the Green Slate Series in the Basement Bed are 
larger than the average. This is well seen under the cliff W.N.W. 
of Twisleton Dale House. A little further east, and more nearly 
due north of the house, there are alternations of beds of con- 
glomerate 8 to 18 inches, with dark grey limestones 12 to 24 
inches in thickness. These beds dip about 10° N.E. in conse- 
quence of the dome-like structure above described. In them 
there are found abundantly fine, well-preserved specimens of 
coral and other fossils. A little further on, N.W. of the sheep- 
fold, which is X. of the stepping stones, we find near some springs 
several feet of irregular conglomerate and clayey debris at the 
base of the Mountain Limestone, and a little more than 200 
yards further to the N.E. there is a black, fossiliferous limestone 
associated with the basement conglomerate. 
The outcrop of the Basement Bed is now entirely obscured 
by drift and alluvium, but it must curve round and cross the 
valley south of the natural feature known as God's Bridge, 
where the river runs under horizontal beds of limestone. About 
200 yards S.W. of this the black limestone is exposed in the 
river bed, and a crushed black limestone with fossils is seen 
again near Light Water Spring, and near by a calcareous con- 
glomerate is seen resting on slate. It appears, therefore, that 
a black, fossiliferous limestone occurs at intervals on both sides 
of the valley from near Dale House to God's Bridge, and this 
has never, as far as I know, been thoroughly worked for fossils. 
Full fists should be made from this well-marked and easily 
recognised zone in the very base of the Mountain Limestone of 
our district. 
