460 S. Y. ^OOD, JTJIT., 01^ THE NEWEE 



tioned, the Walton Crag is overlain by alternations of laminated clay 

 and sand. The elevation of this in the cliff is between 50 and 60 feet ; 

 and at about the same elevation* at Hawks Mill, Needham Market, 

 in the Gipping valley, six miles N.W. of fig. I. a, I found a section 

 of highly micaceous laminated clay passing up into micaceous sand t 

 If this be not the Chillesford Clay, then I think we may infer that 

 the laminated deposit, unconformably covering the Walton Crag is 

 not that clay either, and that this and the rest of the southern part 

 of the Eed Crag remained in the state of land ; but if it be, then 

 the depression described carried the sea not only over the Walton 

 bed, but also up the Gipping valley, though by what route, unless the 

 intervening area was submerged, is not appareut ; for, with the ex- 

 ception of the two patches at Walton and I^eedham, not a vestige 

 of the Chillesford Clay or sand occurs south of Butley, although the 

 Eed Crag ranges south of that place for twenty miles. The Red 

 Crag between the Deben and the Orwell attains, even in its unaltered 

 condition, i. e. with shells, to an elevation of nearly 80 feet at one 

 place (Bealings), and stiU higher at another spot near Sparrow's 

 Nest, three quarters of a mile north of the line of fig. I. a (where it 

 was erroneously shown as a boulder in the sections of the ' Intro- 

 duction to the Crag Mollusca,' Supplement) ; but generally, in 

 both this and in its altered or decalcified condition of red sand, 

 occasionally containing casts of shells, it lies at and below 60 feet, 

 being overlain, without any distuiguishing linet, by from 20 to 

 30 feet of the yellow sand marked ? in fig. I., which seems to me 

 to be a continuation of the Lower Glacial sand hi. Throughout 

 its range from this limit northwards the base of the Chillesford 

 Clay, however, though from the deeper water of the estuary in that 

 direction it descends to Ordnance datum on the coast in the north 

 of Sheet 49, never exceeds, and, I think, nowhere quite reaches, 

 an elevation of 50 feet, which is about that of the patches at Walton 

 and Needham ; and the mollnscan remains preserved in the upper- 

 most beds of the Crag thus overlain show no transitional character 

 to connect them with the shell-bed just under the Chillesford Clay, 

 as do the upper beds of the Eed Crag at ChiUesford and Butley. 

 If, therefore, this clay overspread the intervening area, it doubtless 

 did so unconformably to the Crag of this part, as it does at Walton ; 

 and possibly the highest eminences of this, such as those at Bealings 

 and Sparrow's Nest, were not covered by it. However this may 

 have been, the Chillesford Clay seems to have been completely re- 

 moved over nearly all the marine part of the Eed-Crag area ; and 

 this I infer can only have taken place by the waters of the Lower 

 Glacial sea under which the sands h 1 accumulated, and which sea, 

 removing this clay, covered with its sands the chief part of the 

 south-east of Sheet 50, as well as the extreme north-east of 48, 



* All the elevations mentioned in the paper have reference to Ordnance datum. 



t This had its laminjs at one end turned up to the vertical, evidently by that 

 pressure of the ice, during the later part of the Chalky Clay, vrliich gave rise to 

 the features described in Stages III. and IV. 



\ As to this see the remarks as to Wilford-bridge section in Stage II. 



