278 LIAS OF ENGLAND AND WALES: 
Gayton brickyard, N.W. of Ellsworth, showed the following 
section : 
FT. In. 
f Blue and brown clay with scratched Chalk- 
Boulder Clay 4 stones, flints, &c. - - - 20 to 25 
(Even or gently undulating line.) 
fBlue slightly micaceous clay, with small 
TJ j. I nodules, and slightly calcareous concre- 
"| tionary seam, with Ammonites bifrons, 
[. Nucula Hammeri, &c. - - - 25 
Mr. Thompson records also Ammonites Holandrei, A. serpen- 
timis, Belemnites, Cerithium, DentaUum liassicum, and Inoceramus 
dubius. Fossils are rare, and he considers the clay to belong to 
the " Unfo?siliferous Beds."* 
A lesser thickness of the same beds is exposed in another brick- 
yard near Gayton wharf. The upper portion of the Upper Lias 
clay, beneath the Boulder Clay, is here seen to be very much 
contorted : a feature produced by Glacial action (see Fig. 89). 
A boring at Gayton, was carried through about 8 feet of Drift 
and Upper Lias, 20 feet of Middle Lias rock-beds, and 553 feet 
of other beds of Middle and Lower Lias.f 
The clays extend over a considerable area eastwards to Preston 
Deanery aud Horton, and they have been worked for brick-making 
at Wooton. 
The Upper Lias clay is well shown in brickyards at Northamp- 
ton ; in one known as the Vigo pit, ou the southern side of the 
town, and in three pits near the Kingsthorpe Road on the northern 
outskirts of the town. The clays are exposed beneath a covering 
of the Basement-beds of the Northampton Sands, (ironstone, and 
ferruginous sandstone with nodules), 2 or 3 feet of which beds are 
exposed in places. Beneath, there is usually from 18 inches to 
2 feet of grey shaly and ferruginous clay, which passes down 
into the ordinary blue clay with nodules of argillaceous limestone. 
At Vigo brickyard we see about 30 feet of clay. The fossils met 
with at these localities include the following : 
Ammonites bifrons. 
communis. 
. crassus. 
exaratus. 
heterophyllus. 
Holandrei. 
lythensis. 
serpentinus. 
Nautilus astacoides. 
Belemnites striolatus. 
Voltzi. 
Cerithium. 
Area. 
Inoceramus dubius. 
Leda ovum. 
Pleuromya costata. 
According to Mr. B. Thompson they indicate beds on the horizon of his 
Lower and Middle Leda-ovum Beds. 
Lower down the Nen valley we find brickyards here and there, at Castle 
Ashby, north of the Midland railway-station, Wellingborough, and between 
"Wellingborough and Finedon (Lower Leda beds) ; west of Wellingborough, and 
E. of the L. and 1ST.W. Railway Station (Upper Leda Beds) ; Higham Ferrers 
(Lower Leda Beds) ; and Irthiingborough.J 
* Journ. Northampton Nat. Hist. Soc., vol. iv. p. 215. 
t H. J. Eunson, Quart. Journ. Geol. Soc., vol. xl. p. 484 ; and B. Thompson, 
Middle Lias of Northamptonshire, p. 45. 
J Paper in Journ. Northamptoushire Nat. Hist. Soc., vol. v. p. 62. 
