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another, until close to the site of the bridge under Woolavington 
Lane, when two beds, respectively 4ft. and 5ft. thick, of hard 
blue shale appear, separated by a bed of stone 14ins. thick. 
Underlying these strata are four or five beds of hard whitish 
limestone (White Lias), with beds of shale and stiff blue clay 
about 5ft. thick, and at the base Black Shales. These beds belong 
to the Rhetic formation, and they here form the nucleus of an 
anticlinal. Beyond the anticlinal the Lower Lias strata present a 
gentle synclinal structure, and the beds rise to the north at an 
angle of about 5 degrees. Farther on the Rhetic Beds again 
‘appear, and at the site of the farm bridge the Black Shales show 
a thickness of 12ft. Interstratified in these last are beds of 
fibrous carbonate of lime or “ beef,” one or two feet in thickness, 
‘and under these were some layers with nodules and crystals of 
iron-pyrites. In the lowest bed shown at the site of the farm- 
bridge some teeth and scales of fishes were found. Immediately 
above this there came a bed of bluish limestone, having nodules, 
hollow in the centre, and lined with crystals of carbonate of lime. 
In the Black Shales were also found besides the fish scales, many 
shells common to the Rhetic Beds, such as Cardiwm Rhaelicum, 
Pecten Valoniensis, and Avicula contorta. Further on by the 
Cossington Dingle this succession of peds somewhat abruptly ends, 
the latter part of the cutting being through clays and recent 
rubble. | 
Beyond tle Dingle the line enters another cutting, and, after 
passing through the Rheetic shales and clays, the Lower Lias is 
again found overlying the White Lias with its top layer, the 
“Dew Bed.” The strata here show signs of great disturbance, 
the limestones being very much dislocated, and in places the 
shales and beds of clays are tilted up and cut off within a chain’s 
length. The chief fossil found in the basement beds of the 
Lower Lias was Plewromya Crowcombeia in large numbers. A little 
further east the beds become regular, though frequently faulted. 
First we find shale and rubble cverlying limestone shale in light 
J 
