PLIOCENE PEEIOD m ElfGLAND. 475 



quartz pebble, remaining on downs, even near the Lizard, at eleva- 

 tions of 360 and 400 feet*. 



Northwards from Hampshire the gravel of the great submergence 

 is extensively spread over the high grounds of Lower Tertiary and 

 Chalk in the north of Sheet 12 and south of Sheet 13, reaching 

 elevations of about 600 feet. North-east from this it ranges over 

 the Lower Tertiaries and chalk of the north-west part of Sheet 7 

 and south-east part of 46, gradually, however, falling to somewhat 

 lower elevations as it approaches the edge of the Chalky Clay in the 

 last-mentioned sheet. 



Beyond the chalk escarpment, running through Sheets 15, 14, 34, 

 13, and 46, and outside the limit of the Chalky Clay, the gravel 

 occurs over the Jurassic formatious up to elevations of 539 feet, 

 near Oxford (about the centre of the dividing line between Sheets 

 13 and 45), and to a greater height in the Cotteswold region, occu- 

 pying the east of Sheet 44. The gravels of this region are described 

 by Mr. Hull as reaching elevations of 700 feetf. Mr. Lucy, in a 

 paper on the gravels of the Severn, Avon, and Evenlode, and their 

 extension over the Cotteswold Hills, read before the Cotteswold Club 

 in 1869, and printed for private distribution, has confirmed this, 

 as has Prof. PhiUips also, in his ' Geology of the Thames Yalley.' In 

 this paper and another subsequently read before the Cotteswold Club, 

 Mr. Lucy describes the occurrence of flints in these gravels at ele- 

 vations exceeding 600 feet, and the gravels with quartz and quartzite 

 pebbles up to elevations of 750 feet ; but having found pebbles of 

 quartz and quartzite, which are so characteristic of these gravels, oc- 

 casionally at greater elevations still, he infers that the Cotteswolds 

 must have been entirely submerged. Of this, however, the evidence 

 does not appear to me reliable, so far as it has been made known. 



Patches of gravel at great elevations containing the remains of 

 marine mollusca, like those in the Moel-Tryfaen bed, occur on the 

 western edge of the Pennine in Sheet 81, the highest of which ap- 

 pears to be that found by Prof. Prestwich near the Setter Dog Inn, 

 above Macclesfield, the elevation of which is stated to be between 

 1100 and 1200 feet J, while that so long known from Mr. Trimmer's 

 discovery at Moel Tryfaen, near the Menai Straits, reaches the ele- 

 vation of 1350 feet. In describing Stage lY. I shall explain why it 

 now seems to me that the gravel of these great elevations belongs to 

 the present stage, and not, as I had long supposed, to the close of 

 the Glacial period §. 



* Budge in Trans. Eoy. Geol. Soc. Cornwall, vol. vi. pp. 1 & 91, and Tyack 

 in same, vol. ix., quoted by W. A. E. Ussher in ' The Posttertiary Geology of 

 Oornvfall,' printed for private circulation in 1879. 



t Hull, in Quart. Journ. Geol. Soc. vol. xi. p. 477. 



J Darbishire, in Geol. Mag. vol. ii. p. 296. They have also been found by 

 Mr. Close at 1000 and 1200 feet in the east of Ireland, near Dublin (Geol. 

 Mag. decade ii. vol. i, p. 194). 



§ This cardinal error (which I appear to have shared with all other geolo- 

 gists who have given attention to the Glacial Drift) misled me into supposing 

 that the submergence of the Weald had accompanied the formation of the 

 gravel marked / in fig. VI. (Quart. Journ. Creol. Soc. vol. xrvii. p. 3); for, as 



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