CKOMER FOREST-BED. 
179 
the valves united— as in the CJnio-bed ” at Sidestrand. This 
gravel is seldom laid bare, as it lies beneath the beach level. 
Ninety yards south of this point, shelly Crag directly underlies 
the mammaliferous clays of the Rootlet-bed, rising apparently to 
about half-tide level. Eighty yards further, carbonaceous gravel 
again descends to low-water and has here yielded a good many 
bones. 
For some distance south the section calls for no remark, the 
Rootlet-bed being of the ordinary character, and containing 
scattered bones throughout. About a quarter of a mile north 
of the old Coast Guard Station, six to twelve inches of peat with 
seeds overlie the Rootlet-bed. Then the Forest-bed soon rises 
and tends to thin out, so that the Chillesford Clay reappears 
above the beach. About 80 yards from the flagstaff at Kes- 
singland Mr. Blake found a hollow full of black silt, occupy¬ 
ing the lower-part of the Rootlet-bed. From it he obtained wood, 
seeds, fish-bones, scales of Perch, and bones and teeth of the 
characteristic Upper Pliocene vole, Arvicola intermedins. (Fig. 42.) 
Fig. 42. 
Arvicola intermedins, Newt, (lower jaw, broken to shoiv the 
fanged teeth). 
Twice natural size. 
This is the most southerly point at which the Forest-bed has 
yielded fossils. The weathered soil can be traced as far as the 
end of the cliff; though this part of the section is usually 
obscured by sand dunes, and has not produced fossils. 
Where the cliffs recommence, at Covehithe, the Forest-bed has 
disappeared, and pebbly sands rest directly on the Chillesford 
Clay. There may possibly be a trace of the old land-surface, for 
the upper part of the clay is penetrated by roots. These, however, 
are considered by Mr. Whitaker to belong to recent plants! 
The only other deposit that is at all likely to represent the 
Forest-bed, is the clay with lignite, above the Crag in the cliff 
at Walton Naze (see p. 83). This deposit is usually referred to 
the Chillesford Clay, and in the absence of fossils nothing more 
can be said about it. 
On attempting to compare the fossils of the Cromer Forest-bed 
with those of the underlying Crag, we meet with considerable 
difficulty. In the one case we are dealing mainly with a land 
fauna and flora; in the other, with little but marine mollusca. 
This has often led geologists to think that a considerable break 
