422 LOWER OOLITIC ROOKS OF ENGLAND : 
the western side of the valley the Great Oolite Limestone was 
exposed in trial-pits. The formation consists of hard earthy and 
shelly limestone, with (on top) a band crowded with Ostrea 
subrugulosa. Above, there was to be seen the Great Oolite 
Clay, comprising brown, grey, green, and purplish racy clay, with 
an included band of hard marl Cull of oysters, chiefly Ostrea 
subrugulosa. Overlying the Great Oolite Clay, came the Corn- 
brash, with Ostrea flabelloides, Grcsslya peregrina, &c. ; and this 
formation was overlaid by clays and sandy strata belonging to the 
Kellaway's Beds. 
Further west there was a cutting in Great Oolite Clay and 
Cornbrash, the position of which indicates the presence of a fault 
(of no great magnitude), which traverses the ground in a direction 
a little west of north, and about 300 yards west of Elder wood 
Farm.* The section of the beds, in descending order from west 
to east, was as follows : 
FT. IN. 
Oxford Clay. Kellaways Beds, seen south of Home 
Bottom Farm, 
Cornbrash. Rubbly and flaggy limestone. 
"Nodular compact and shelly limestone, in"| 
brown racy clay. I -, /, 
Clay with" race " : Ostrea subrugulosa and [ 
Purple clay 
Ostrea-bsmd - - - - ^ 6 
Green clay 
_Traces of red ironstone nodules - 
The Great Oolite Limestone, which must come on below, was 
not here exposed. 
Shallow cuttings in chalky Boulder Clay extend from the 
south of Pells and Dobbin Woods to a little west of the disused 
Little Bytham and Edenham Railway. Along portions of th : s 
tract large blocks of fossiliferous Great Oolite Limestone w*-re 
brought from the cutting on the west, to be broken up for ballast. 
On either side of the disused railway the Boulder Clay was seen 
resting on Great Oolite Clay. The Boulder Clay here, as in 
other exposures along this Midland railway, contains numerous 
glaciated Chalk-stones, together with flint and a good deal of 
Jurassic material. It is, however, noteworthy that Oxfordian 
fossils (Gryphcea dilatata) occur here amid the Chalk detritus, 
while further west Lower Oolitic material is noteworthy, and still 
farther west I found many Lower Lias fossils. In the cutting 
to which attention is now directed, and which is to the north-east 
of Little Bytham station (on the Great Northern Railway), the 
Great Oolite Clay presents its usual characters of grey and green 
clay and loamy clays, with Ostfrea-bands, and with nodules of red 
* This little fault was not shown on the Geological Survey Map, and consequently 
the beds above the Great Oolite Limestone to the east of it, were not represented 
in the little spur on which Elderwood Farm stands. In other respects the new 
railway confirmed the mapping of the strata, by Prof. Judd, with the exception of 
the fact noted further on p. 423. 
