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quarries near Sudburne pointed out to him by Mr. Bunbury. At 
Tattingstone the coralline crag consists chiefly of greenish marl, 
with discontinuous layers of stone, and the number of corals is 
very small; but both at that locality and Ramsholt, the red crag 
rests on denuded beds of the coralline. At Sutton, near Wood- ‘ 
bridge, Mr. Lyell was enabled to ascertain, by the assistance of 
Mr. W. Colchester, that the red crag in some places abuts against 
a vertical face of the coralline, as well as overlies it; and that 
in consequence of the irregularities in the outline of the face, the 
two deposits have a deceptive appearance of alternating. He also 
ascertained, in addition to the above evidence, that the older or 
lower strata must have acquired a certain consistency before the 
newer were accumulated, because the calcareous sand or comminuted 
shells and zoophytes, of which the former are composed, is perfo- 
rated to the depth of 6 or 8 feet from the surface by the tortuous 
borings of pholades, the shells of which are frequently found at the 
bottom of the tubes, the remainder of the perforations being filled 
with the sand of the superjacent red crag. The most northern 
point to which the coralline crag has been traced, is Sizewell Gap, 
several miles north of Thorpe. 
2. With respect to remains of mammalia being imbedded in 
undisturbed marine beds in the Norwich crag, Mr. Lyell stated, 
that an examination of this crag in the neighbourhood of Southwold 
and Norwich had convinced him, that instead of the deposit being 
purely marine, it is fluvio-marine, containing every where an inter- 
mixture of land, freshwater, and sea-shells, with the bones of 
mammalia and fishes. The formation is exposed along the coast, 
at Thorpe, near Aldborough, where it may be seen at low-water 
resting on the coralline crag; butit is most largely developed in the 
neighbourhood of Southwold, where the author examined it accom- 
panied by Capt. Alexander. In that district, it varies greatly in 
character, consisting of irregular beds of sand, shingle, loam, and 
laminated clay; but it appears to have been in some places tran- 
quilly accumulated, as specimens of Nucula Cobboldie, Tellina obliqua, 
and Mya arenaria, occur with the valves united, and not worn by 
attrition. In the same beds, however, are procured rolled fish- 
bones, and remains of the elephant, rhinoceros, horse, and deer. 
Capt. Alexander found at the base of the cliff, in a bed about 6 
inches thick and rich in marine shells, the tooth of a horse within a 
large Fusus striatus. That gentleman also possesses a tooth of a 
mastodon, washed out of the cliffs between Dunwich and Size- 
well. 
In tracing the Norwich crag from Easter Bavant northward to- 
wards Kessingland, Mr. Lyell found in it layers of flinty shingle ; 
and he consequently refers to this formation, those strata of sand 
and shingle, on the coast, which resemble the sandy portions of 
the plastic clay of the London and Hampshire basins. 
In some of the inland pits of Norwich crag near Southwold, the 
author found mammiferous remains associated with a variety of 
Cyrena trigonalis, a shell common in the freshwater deposit of Grays, 
and elsewhere. 
