MIDDLE LIAS : MARKET HARBOROUGH. 231 
Survey Map) has been generally taken on top of the stiff blue 
clays, that belong in part to the zone of Ammonites margaritatus. 
Thus near Welton Station, clays, yielding Ammonites marynri- 
tatus, A. Engelhardti, and also Lower Lias species, have been 
dug in a brick-yard. (See pp. 166, 226.) 
" The exact boundary between the Lower Lias and the Marl- 
stone, north and east of Weedon [Beck], is uncertain, the ground 
being thickly covered with drift."* 
Outliers of Marlstone occur at Bodington, Napton Hill, Upper 
Shuckburgh, Welton, Watford Gap, and Barby Hill.f 
Marlstone (hard calcareous sandy and ferruginous rock) has 
been quarried near Brockhall and Whilton, and the rock has 
been exposed near Long Buckby and Watford. The lower beds, 
consisting of sandy and ferruginous shales and clays, with hard 
concretions, have been opened up at Murcot, near Long Buckby, 
and at Winwick. As remarked by Mr. Aveline, inliers of Marl- 
stone may occur to the south-east, near Cottesbrook, in the valleys 
of the Stowe and Callender brooks, -where some rock-beds were 
observed during the progress of the Geological Survey, but the 
beds occupy too small a space to be clearly represented on the 
inap.J 
North-east of Elkington the Marlstone appears to be repre- 
sented by soft beds of sandstone an 1 sandy marl, while in the 
neighbourhood of Welford the beds are concealed by Drift. 
Leicestershire, Rutlandshire, and Lincolnshire. 
The poor development of the Marlstone (as a rock-bed) in 
parts of this region, was shown in cuttings of the railway between 
Northampton and Market Harborough, near Oxenden Magna, 
where according to Mr. Aveline the beds are represented by 
sandy shales and a few concretionary beds ; nevertheless the beds 
form a striking escarpment at East Farndon and the Holthorpe 
Hills, north of Sibbertoft. In the outlier at Guinley no bard 
beds were seen, soft ferruginous sand being observed beneath a 
covering of Drift. 
The lower beds of the Middle Lias were shown in a brick- 
yard at Little Bowden, south of Market Harborough station : 
FT. IN. 
M' 1 11 f Slightly micaceous and sandy shale?, with, at base, 
< ochreous nodules with Ammonites margaritatus 
I and Gasteropoda - 5 
Lower f Grey shales passing down into blue clay, with 
Lias. 1. Ammonites capricornus - - - 55 
* Aveline and Trench, Geol. part of Northamptonshire, p. 5. In this work, 
fossils from the Middle and Upper Lias are not separated. 
| Rep. Rugby School Nat. Hist. Soc., for 1869, p. 27, and 1878, p. 44. 
j Geol. parts of Northamptonshire and Warwickshire, p. 6. 
Aveline and Howell, Geol. of part of Leicestershire, p. 5. 
