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Westbrook the prevailing fossil is a small species of Astrea. 

 At Hannington Hill, neai' Highworth, CaryophylUa form the 

 entire mass of the Coral Rag, but at Steeple Ashton both these 

 genera are associated with Agaricia." 



In Yorkshire the Coralline OoUte is well developed, and 

 several reefs are found at Hackness, Ayton, Seamer, &c. I 

 am indebted to my friend John Leckenby, Esq., F.G.S., of 

 Scarborough, who kindly undertook, at my request, for this 

 paper, an examination of the Coral beds at Hackness, and 

 Ayton, &c., and has contributed the following important note 

 on the subject : — 



"In various parts of the district occupied by the Coralline 

 OoKte around Scarborough, are fotmd patches of Coral reef 

 sometimes occupying an area of fully an acre; and although 

 never attaining an altitude so high as the beds on the inclined 

 surfaces of which they rest, they are truly the uppennost beds of 

 the formation. 



"They are sometimes from 10 to 15 feet in thickness, and 

 consist of a series of layers of crystaUized Coral from 18 to 

 24 inches in thickness, of the species Thamnastroea concinna, 

 Goldf., (which is the T. micraston, PhiUips,) each layer being 

 separated by rubbly Clay and mud, in all probability being the 

 decomposition of each successive reef. The rock is quarried to 

 supply material for repairing the roads of the district, but it is 

 by no means so well adapted for the purpose as the adjacent 

 Calcareous Grit, which, at the cost of a Httle additional laboTir, 

 would fiu-nish a material much more durable. The crystalhne 

 Coral reef is quickly ground to powder, and its use affords less 

 satisfaction to the traveller than to the Geologist, as the blocks 

 which are stored up for use along the sides of the road yield 

 many a handsome specimen to adorn his collection. 



" The largest deposit is near the village of Ayton ; there are 

 others not quite so extensive : one near the village of Seamer, 

 another close to the hamlet of Irton, and others in the 

 neighbourhood of Wykeham and Brompton — the intervening 

 distances being about a mile in every case. 



M 



