44 DISTRICT OF TABULAR HILLS. 



found about Cave. The lower calcareous grit and coralline oolite are 

 extremely well connected from Scarborough round the vale of Pickering 

 to Acklam, but they have not been seen further south. Whether the 

 calcareous rocks which range close under the wolds of Lincolnshire 

 belong to this formation, I have no means of ascertaining. The upper 

 calcareous grit covers the coralline oolite at Stonegrave, Oswaldkirk, 

 Ampleforth, and Wass bank, and, in lower ground, at Helmsley, Kirk- 

 dale, and Sinnington*. It also occurs, as Mr. Smith informs me, in the 

 same manner on Silpho Brow, near Scarborough. 



That all the strata of the tabular hills should be included in one 

 formation, appears to me satisfactorily demonstrated by the gradations 

 they present between each other. Thus the Kelloways rock changes 

 into the Oxford clay, which is still more evidently blended with the 

 lower part of the calcareous grit. The calcareous grit and coralline 

 oolite above, are so harmonized at their junction, that it is not easy to 

 mark the exact line ; and the similarity of character between the upper 

 and lower beds of calcareous grit completes the evidence which warrants 

 the combination of all these strata into one natural group. 



Whoever compares this series of strata with the coralline oolite for- 

 mation in Berkshire and Wiltshire, will find them extremely similar in 

 the mode of arrangement, in mineralogical composition, and organic 

 contents. The features which they impart to the country are much 

 alike in both districts, and the whole evidence in favour of their affinity 

 is complete and satisfactory. Yet the two districts lie wide asunder, 

 and in all the intermediate tract a great portion of the series is unknown. 

 From Acklam to the neighbourhood of Oxford, no coralline oolite or 

 calcareous grit appears at the surface, (unless the limestone before men- 

 tioned in Lincolnshire, belongs to these rocks,) and the Kelloways rock 

 has not yet been described between Huntingdonshire and the Humber. 

 This should teach us not to undervalue the evidence of organic remains, 

 for these are always useful and often necessary guides to determine the 



* See Phil. Mag. and Annals of Philosophy, April, 1828. 



