Fisher — Denudations of Norfolk. 545 



Norwich, Ilorstead, and Coltishall, and I see no reason to doubt that the rem- 

 nants of ferruginous shelly gravel adhering to the surface of the Chalk on the 

 beach at Lower Sherringham belong to iL 



Section at the base of cliff at the first point west of Lower Sherringham. 



a. " Laminated beds," sand, gravels, and clays. 



b. Ferruginous gravel cemented by iron oxide; a piece of deer's horn was found in it. Pro- 



bably the Elephant bed. 2ft. oin. 



c. Blueish grey sandy clay, micaceous, and containing drifted lumps of the same. Probably 



the Forest bed. 2ft. 6in. 



d. Ferruginous pan, with large flints and abundance of Cyprina Islatidica, Probably Nor- 



wicli Crag. ift. 6in. 



e. Chalk rising above the beach, ift. 6in. 



N.B. — This is the most complete section which I have seen, and if the strata are correctly 

 determined, it shows the entire sequence. 



The appearance of the chalk at Bungay, and of the Upper Norwich Crag at 

 Aldeby, near Beccles, would lead us to place the junction of the two deposits some- 

 where between Beccles and Bungay,^ and it may be remarked that, on account of 

 the low level always occupied by the Crag, there is reason to believe that when 

 we approach the boundary of that formation, we are in the neighbourhood of its 

 veritable coast line. Moreover, the abundance of the bones of gigantic probos- 

 cidians, found at Horstead and Norwich (but especially at the former place) among 

 the flints which constitute the base of the deposit, prove that at those points the 

 land could not have been far distant. We have no data at present, that I am 

 aware of, for determining the nature of the coast line of the Crag sea, but it was 

 probably a line of cliffs extending in a direction somewhat parallel with the present 

 eastern coast of Norfolk, and about twenty miles westward of it. 



In the neighbourhood of Yarmouth, however, a different condition of things 

 must have obtained ; for there the London Clay covers up the Chalk, - and owing to 

 the softer character of that stratum, it is probable that the sea was deeper over it, 

 and the Crag deposit probably somewhat modified in its character. 



Indeed there seems to have been from early post-Cretaceous times a depression 

 of erosion in the course of the valley now occupied by the Waveney and Little 

 Ouse, which separates the counties of Norfolk and Suffolk. In the well section 

 at Diss, given by Mr. Gunn,^ 200 feet of superincumbent strata were pierced before 

 the Chalk was reached, and then only 330 feet of chalk-with-flints were found re- 

 maining ; whereas at Norwich 1050 feet is the thickness of that bed. At Yar- 

 mouth the Chalk was not passed through, so that we learn nothing from the sink- 

 ing there respecting an early excavation of the Chalk. 



' See Trimmer's Geology of Norfolk, Jour, of |R. Agricultural Society, vol. vii., p. 449, note. 

 * Prestwich, Quart. Jour. Geol. See, vol. XVI., p. 449. 

 ' Geology of Norfolk, p. 7. 



