DEPOSITS AND ELEVATION. 35 



Note as to ^' Pholas'^ -holes at high levels in Derby- 

 shire, from the Proceedings of the Society, ist Oct. 1867. 



Mr. Darbishire referred to a paper ^' On tlie Existence 

 of a Seabeach on the Limestone Moors near Buxton^' 

 (Trans. Manchester Geol. Soc. v. p. 373), in which Mr. 

 John Plant, F.G.S., had described as seabeach the surface 

 of the limestone rock as the same is seen when bared of 

 sward and surface clay above the quarries on Grin Edge 

 and Harper Hill, south-west of Buxton, and to Mr. Plant^s 

 conjecture that this worn surface probably extended nearly 

 to the crown of the hills. 



His own observation had marked on each hill, above 

 the stratum whose upper surface exibited those indications 

 of supposed sea-wear, a stratum of somewhat different tex- 

 ture still subsisting in the shape of a slight vertical cliff or 

 reef. This bed had not been worn in the same manner as 

 the so-called " beach " (that is to say, with many interla- 

 cing fissures leaving a close chevaux-de-frise of limestone 

 points), but rather in great blocks with round, curved 

 edges or holes. 



In connexion with this bed Mr. Darbishire had obtained 

 specimens from each hill, exhibiting what he believed to 

 be the remains of the burrows of Pholas or some similar 

 shells. 



On the top level of Grin Edge, close to the ruins of the 

 tower, one stone had a group of seven holes. They were 

 placed like Pholas-holes as he had collected them on Great 

 Orme^s Head; and, though the sui'face of the stone about 

 them was much worn, taken along with the specimen next 

 described, it seemed more fitting to ascribe to them a 

 similar origin than to attribute them to the natural wear 

 of the stone, notwithstanding the variety and singularity 

 of many of the forms in which atmospheric or aqueous 

 corrosion affect the limestone rock. 



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