289 
THE LOWER PERMIAN AT ASHFIELD BRICK AND TILE WORKS, 
CONISBOROUGH. 
BY ALBERT GiLLiGAN, M.sc. (Leeds), B.sc. (Wales), F.G.S. 
(Read November 25th, 1915.) 
This section has long been under observation by Yorkshire geol- 
ogists, but no detailed record has hitherto been given of the Lower 
Permian beds as exposed here within the last few years. The chief 
interest has been centred upon the Upper Coal Measures upon which 
the Permian rests, beds which have yielded a rich harvest of fossil-plants. 
The top-most bed of the Coal Measures is a fine-grained micaceous 
sandstone deeply stained with hematite. The surface of this sandstone 
is undulating, and in the hollows are found deposits of Permian age, 
consisting of conglomeratic material. The largest pebbles in this 
conglomerate are in general not more than an inch in diameter, but 
during a visit to the section in September, 1915, some large boulders 
up to eighteen inches in diameter, were found, which had been taken 
out of the conglomerate by the workmen. These boulders consisted 
of sandstone, identical with the underlying Coal Measure sandstone, 
and a dense siUceous sandstone also possibly a Coal Measure type. 
Intercalated with this conglomerate are beds of fine sand, which 
sand is in all respects, except colour, like the sand which occurs 
in similar stratigraphical positions along the edge of the Permian 
escarpment from North-east Durham to Yorkshire. As the section 
shows, this lowest bed is in its thickest part about 5 ft. 6 ins., but in a 
distance of 15 ft., it has thinned away to 15 ins. of fine sand with very 
few pebbles. Resting upon this bed and traceable right through the 
quarry is a bed of chocolate -coloured marl, the junction with the 
conglomerate being quite sharp. From this bed I obtained, some years 
ago, casts of Schizodus and these appear to be the only fossils present 
in the beds below the massive Magnesian limestone. The chocolate 
marl is succeeded by other thin bedded gre)^ and brown marls, with 
some of which ( as in beds E and H in section) are intercalated bands 
of buff -coloured limestones. 
It will be noted from the chemical analyses given in the appendix 
that the intercalated limestones are highly dolomitised, while the 
insoluble residue in all the marls is very high, the kaolin reaching 
