INTRO DUCT ION. 15 



Tims the Cornbrash is isolated amongst clays. The upper part is here 

 characterised by Alectryonia. 



23. Yaxley oe Stilton. — Under one or other of these names numerous and 

 important fossils have been recorded, but nothing can be seen in the district at the 

 present time. The fossils were obtained from an opening between the two places 

 named, now grassed over, but originally sunk through Oxford (May till it reached 

 hard beds referred to the Cornbrash. These do not seem to have been pierced, 

 so that it resembles the pit at Sutton Benger, in Wilts. 



24. Peterborough. — Along the sides of the united railways north of Peter- 

 borough Station a considerable area of Cornbrash is exposed, three or four feet in 

 thickness, but part of it is left as a floor, so that the base is not visible. It is 

 probably thicker than when last seen at Kineshade, twelve miles to the west, as it 

 spreads over an area at various deviations in the city and extends by the roadside 

 as far as Walton. But the best exposure made in the area is near Castor, where 

 is a quarry on the west side of Milton Park. Here is seen eight feet of pretty 

 solid stone weathering in the usual irregular lenticles. This is said to rest upon 

 clay. The rubbly character of the base is not shown, but the higher bed is 

 indicated by the abundance of the Macrocephalites in it. 



25. Area north of Peterborough. — In the undulating country north of Peter- 

 borough to the neighbourhood of Lincoln numerous Cornbrash localities have been 

 quoted, but they are mostly unverifiable at the present day, as was to be expected. 

 I have not found in this area any locality yielding a section through the Cornbrash 

 so as to show its complete development. All sections are only shallow openings. 

 One is seen on the road towards Market Deeping, four miles out of Peterborough, 

 behind an Oxford Clay pit. Signs of the Hanthorpe pit, where Terehratula 

 bentleyi was first found, are still recognisable. At Quarrington, on this side of 

 Sleaford, a road-stone quarry still exists. At Roxholme a typical shallow opening- 

 is worked while it lasts. At Sudbrook, east of Lincoln, there is still the edge of 

 the old working that has yielded so many fossils, and six miles further on a new 

 shallow opening has been made, at Walton. 



26. Outliers to the West oe the Continuous Range. — The outliers that are 

 found near Northampton owe their position to having been let down by faults 

 along with the strata on which they rest. In the case of Stowe Ninechurches 

 these consist of a complete sequence of beds from the Oxfordian Clays to the 

 Upper Estuarine Beds. It is plain from this that the Cornbrash must be 

 included. Mr. Beeby Thompson, who first described it, assigns a single bed to 

 the Cornbrash, the upper part of which contains characteristic fossils, the lower 

 part containing only the demoid forms which are common to more than one 

 horizon. This exposure is also remarkable for the last presence of the Forest 

 Marble, known by the quality of stone and the presence of vegetable remains, 

 and still only demoid fossils — that is, fossils common also to the Cornbrash. Other 



