nate fluviatile seams, and, in proceeding westward, instead of an occasional seam of Mytili or Myoe or a few Littorinoe, we get fossiliferous beds so like the Norwich Crag that they were always referred
Fig. 38. — Section of the Westleton Beds on the side of Runton Gap.
feet. feet.
a. Valley-gravel.
6. Boulder-clay 8 to 10
5. Beds of light-coloured sand and flint-shingle, with shells at X, and a freshwater peaty bed at X X 12 to 15
to that series. But Mr. Searles Wood, jun., on palaeontological evidence, places them on a higher zone. The difference between Mr. Wood and myself is, that I think the lowest beds " 2' " from Runton to Weybourne should be referred to the true Norwich Crag, whilst I would refer the upper shell-beds " 5 " to the Westleton series, instead of putting them all together, as I believe Mr. Wood does, into one zone, higher than either of these *. At this part of their range there is, with the exception of the presence of the more numerous fossils, little difference in their character from that of the same beds in the neighbourhood of Southwold, where the fossils are rare and, with few exceptions, in the state of casts and impressions only†.
Taking a line from Weybourne to Norwich, the Westleton beds are scantily exhibited over the Chillesford Clay at Burgh and Oxmead. At Coltishall they are more fully developed and contain a subordinate bed of iron-sandstone and clay-ochre, 1-1/2 ft. thick, which reposes upon a slightly denuded surface of the Chillesford Clay. At Horstead the Westleton shingle with crag- shells overlies the Chillesford Clay (ante, p. 459). This is the shelly bed to which Mr. S. Wood, jun., has applied the name of " Bure- Valley Crag." It is seen again at Belaugh‡, and still better at Wroxham. At the latter place there are two pits, in one of which a thin bed of Norwich crag, with numerous single valves of the Cyprina islandica, overlies the Chalk, and underlies a thin bed of clay, representing, probably, the Chillesford Clay, and in the other the same clay is overlain by a sandy crag characterized by the presence of numerous Tellina balthica.
I have already (ante, p. 456) shown the relation of the typical
- Quart. Journ. Geol. Soc. vol. xxii. pp. 547-549. The only other alternative
that I could admit is, that they all belong to the Westleton series.
† I have one perfect valve of Tellina balthica from near Pakefield.
‡ Freshwater shells again appear in these beds. I found, this autumn, in a pit near the Anchor Inn, Coltishall, Limnoea palustris associated with Tellina balthica, Mya arenaria, Cardium edule, Littorina littorea, and Cyprina islandica.
