Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/481

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of that shell in it. "When I again visited it lately to collect more of the fossils, I found it sloped over.

The clay contained numerous impressions of the same shells as at Iken, and in the same condition ; but in the sand the shells themselves were preserved, mostly double and in the position in which they lived. They consisted of : —

Cardium. Nucula or Leda.

Mya truncata. Tellina.

Crossing the Aide, the hill at the back of Aldborough is capped by the Chillesford clay, with the sands under it, and we again find it at the brick-pit near "Warren House, one mile N. of Aldborough ; but in neither of these places have I found any fossils. Their relation at the latter place, both to the Red Crag and Coralline Crag, is clear, as shown in the following theoretical section : —

Fig. 20. — Section from the Railway to the High-road, near Warren House : height about 25 feet.

a. White sands and gravel. 2. Red Crag.

3. Chillesford Clay. 1. Coralline Crag.

3'. Chillesford Sand.

The shell-bed on the side of the road to Saxmundham shows also, apparently, the same relation to the Chillesford Clay, if we may judge by a bed of clay which crops out near the top of the hill.

These Chillesford clays form with the underlying sands the upper division of the Red Crag.

Before leaving this district, I must direct attention to some sections of much interest, both on the score of old physical geography and in evidence of the dependent relations of the Red to the Coralline Crag. To the first of these sections attention was originally directed by Sir Charles Lyell in 1838. In his description of the Crag at Sutton, Sir Charles pointed out that in the Bullock-yard pit on Mr. Colchester's farm the Red Crag abuts against the Coralline Crag, and that the latter is perforated by Pholades, showing the existence of an old cliff, and that this cliff was subsequently submerged and covered up with Red Crag. The further opening out of this section and some other sections on the opposite side of the hill show that there are two submerged cliffs, that they pass round the hill, and that the mass of Coralline Crag, forming the higher part of the hill, has been an old reef in the Bed-Crag sea. We have additional evidence also showing how great was the denudation and removal of the Coralline Crag, the debris of which is profusely scattered in some adjacent beds of the Bed Crag. The facts were of so much interest that I resolved to have a properly levelled section taken of the whole