380 J. F- BLA.KE AND W. H. HUDLESTON ON 



The above list is by no means exhaustive ; but it may be deemed 

 fairly characteristic of the Rag horizon in this locality. Species here 

 seem to have attained, as regards individual growth, their maximum 

 development ; and some forms such as Astarte ovata are nearly twice 

 the size of those occurring in the oolites. It is quite possible that 

 in this way species really occurring in the lower beds, having as it 

 were outgrown themselves, are no longer recognized. 



1. The Cement-Stone. — There is no section on North -Grimston 

 Hill where this formation can be seen in actual superposition 

 upon the Coral Rag. In the neighbourhood of the great quarries, 

 south-west of the line of section, the slope of the hill and the dip 

 of the beds are so rapid that a considerable portion of the cement- 

 stone has fallen completely over, and may actually be seen in the 

 railway-cutting with the dip apparently reversed. It will be 

 necessary therefore to follow the line of section (fig. 22) in order to 

 read the sequence. 



From the northern edge of the escarpment the Coral Rag keeps 

 the surface of this salient promontory as far as the Wharram road ; 

 and the section cuts that road at a point where the Rag ceases to 

 appear on the lower side. Here, as indicated in the section, we 

 find the Cement-stone in situ ; and there is every indication that it 

 forms the surface of the slope from this point in a south-easterly 

 direction. It is quarried extensively at the point marked " 300 

 feet," just above the railway (y of the section). There are 28 feet 

 of beds exposed here, making, with 8 feet more proved by boring, a 

 total of 36 feet without reaching the bottom. The dip in the 

 upper part of the quarry is about 4° S.S.E. ; but lower down, 

 towards the railway, these dips increase rapidly, keeping pace appa- 

 rently with the surface-slope. Fragments of a similar kind of stone 

 are met with in Burdale beck, on the south bank of which is an 

 old quarry in one of the harder beds, whence the stone used in 

 building Wharram church is said to have been extracted. A short 

 distance south of this is Lord Middleton's brickyard, unfortunately 

 now no longer worked. This is unmistakable Kimmeridge Clay, 

 Avith abundance of selenite, fragments of deltoid oysters, and the 

 sept aria characteristic of that formation *. The sequence is the 

 same as at Hildenley. On the north side of the brickyard the 

 " hard stone " was proved at a depth of 12 feet ; but on the south 

 side none was found at twice that depth, showing that the supra- 

 coralline beds are getting deeper, or failing in a southerly direction. 

 This " hard stone " is of very inferior quality to the cement stones 

 of the principal quarry, and is probably higher in the series than 

 any there proved ; it contains more sand, and has some of the 

 features of a calc-grit. , 



The lithological aspect of the Cement-stone, as shown in the 

 principal quarry, and in numerous exposures in the valley between 

 the Corallian ridge of Langton-Grimston and the Chalk escarpment, 

 is quite that of a " lias;" that is to say, it consists of hard argillo- 



* Stories are told of cartloads of septaria and many Ammonites having been 

 taken away by the farmers. 



