1 78 S. A. ADAMSON : AMONGST THE YORKSHIRE OOLITES. 



' slickensides ' — that is, polished surfaces arising from the sUpping, 

 and therefore grinding, of the chalk (similar to those we see so often 

 in the coal measures) — or whether it was a form of incipient crystalli- 

 sation ; or, again, all that is left of some low form of animal life. 

 Some good examples were brought away for careful examination 

 afterwards by the microscope. Arrived at the summit of the hill, a 

 magnificent expanse of country presented itself, affording a good 

 opportunity for the Rev. E. Maule Cole, M.A., to describe the 

 general contour and physical geology of the district. To the left 

 were Acklam Wold and other hills of the chalk, passing northward 

 the Oolitic hill of Langton Wold, then succeeded the Howardian 

 Hills and a view of Ryedale, whilst to the extreme right could be 

 seen the moorlands and Tabular Hills. This striking panorama 

 was further enhanced by the cloudless sky and bright sunlight. 

 Descending, the Wharram Road was taken in the direction of 

 North Grimston, and on the road-side a small outcrop of coral rag 

 was noted. The party now arrived at the large North Grimston 

 Limestone Quarries on either side of the Wharram Road, which 

 present such a full section of the coral rag proper or Upper Coralline 

 Oolite. This section (said to be the finest development of coral rag 

 in England) is so valuable that a brief description in descending 

 order may be quoted for reference : — ' Buff-coloured limestones with 

 yellowish markings ; beds of white stone, seldom hard and crystalline 

 like the series below\ Indications of corals moderate ; flints rare. 

 Beds less shelly than low^er series. The foregoing have a thickness 

 of about 20 feet. Then succeeds a thin parting of soft yellowish 

 brash, followed by about 1 7 feet of white sparry and compact lime- 

 stones in strong, massive blocks, which become largely charged with 

 flint, especially about 6 feet above the base of the series. The great 

 shell bed in this part of the section is about 3 feet thick, and is a 

 mass of splendid fossils, all of them the finest and largest of their 

 kind. In the west end of the lower quarry, on the south side of the 

 road, the urchin beds are well developed. These beds were observed 

 to dip rapidly to the south, probably a dip of about 25 degrees.' 

 The line of railway was now pursued to Settrington, and in the cut- 

 ting here and there some good sections of coral rag and coralline 

 oohte, part of the old coral reef, were disclosed. The quarry near 

 Settrington Station was then examined. Here the upper part is 

 coral rag, resting upon coralline oolite. Professor Green secured at 

 this quarry a good specimen of Isastrcea. Return was then made by 

 rail to Malton. Passing through the town, the site of the old Roman 

 camp was visited, and the section in the railway-cutting of the 

 ancient refuse heap or midden was pointed out. The noted section 



Naturalist, 



