462 S. V. WOOD, JTJN., ON THE NEWEK 



enveloped the northern part of the kingdom, and terminated in the 

 principal branch or branches of this river. The preglacial valley 

 through which this river flowed from North Britain appears to me 

 to have been that in which the town of Cromer stands, and in which 

 the greatest thickness of the beds described in Stage II. have accu- 

 mulated. At the time of the Crag this part of it stood higher than 

 now, its slope having been changed by the depression that intro- 

 duced Stage II., the relative height of the area in the south-east of 

 Sheet 68, and the adjoining parts of 6Q and 67, having also been 

 changed by the same cause, and by the great reversals of inclination 

 which England underwent during the period examined in this 

 memoir. The gentle slopes of this valley have, however, remained 

 unaltered by these movements for some miles on either side of 

 Cromer ; for while beneath that town the chalk sinks to low- water 

 mark or below it, it rises from there gradually both to the east and 

 west, so as to attain the beach-surface above high-water mark about 

 four miles to the east and two and a half miles to the west of the 

 town. On the surface of this flat valley of chalk grew the vegeta- 

 tion which has long been known as the Eorest-bed ; and in swamps, 

 meres, or tributary streams there were accumulated the clays with 

 land and fresh- water Mollusca and mammalian remains associated 

 with it. These beds are thus, in my opinion, of Crag age, and the 

 mammalian remains preserved in them those of the Mammalia which 

 then inhabited England — all those remains found in the Crag itself, 

 even the fluvio-marine portion, or most of the latter at least, being 

 derivative and belonging to inhabitants of some period or periods 

 antecedent. The clay with mammalian remains, which has its sur- 

 face penetrated by roots, and out of which a hollow has been 

 scooped and filled in with a laminated freshwater deposit, con- 

 taining at its base a bed of Unios at Kessingland and Pakefleld 

 Cliff (north of Sheet 49), and which is there overlain directly by the 

 Middle Glacial (c) and the Chalky Clay (d), is not of the same age ; 

 and though mammalian remains from it have, by the use of the 

 term " preglacial forest-bed," been confounded with those from the 

 beds just mentioned, this freshwater and mammaliferous formation 

 is later than the Crag, since it occupies a valley scooped through or 

 out of the Chillesford Clay, and at one end of this it rests on that 

 clay*. The eastern side of the original Crag valley in which these 

 forest-beds of Crag age thus accumulated extends from Cromer nearly 

 to the south-eastern extremity of Sheet 68 ; for to that distance these 

 beds show themselves along the coast beneath the formations of 

 Stage II. Yery near to this extremity these formations, thinning 

 much, sink below the beach-line, and the further extension of the 

 forest-beds becomes concealed ; and though the Contorted Drift rises 

 above the level of the sea here and there in the interval, it is not 

 until the north of Sheet 67 is entered that this formation rises to 

 any height above Ordnance datum ; but^s it does so, the cliff, which 

 should present a section of it, overlain by the Middle Glacial and the 



* See Section of this cHff by Harmer, Quart. Journ. Geol. See. vol. xxxiii. 

 p. 134. 



