CORALLINE CRAG. 
35 
At this spot the surface of the London Clay lies only 8 feet 
above the level o£ the Deben, and Prof. Prestwich considers that 
a lower zone of Coralline Crag exists here than is represented in 
the Bullock-yard Pit. 
On the opposite side o£ the river Deben^ at the large coprolite- 
working north-east of Waldringfield Church, Mr. Stollery, the 
foreman, told Mr. Whitaker that, in places, some 6 inches of 
Coralline Crag had been got beneath the nodule bed of the Eed 
Crag. 
At Trimley, about five miles south-south-west of the Sutton 
outlier, as already mentioned. Coralline Crag is said to have been 
observed in the digging of a ditch.* * * § The exact locality is not 
mentioned, and no trace of an outlier was observed during the 
progress of the Geological Survey of the district. Altogether 
the evidence seems insufficient to prove the occurrence of 
Coralline Crag here, and the bed may possibly be merely a 
light-coloured unoxidized portion of the Ked Crag, or even a 
derivative boulder from the older deposit. 
The only outlier of Coralline Crag that remains to be described 
is found at Tattingstone Hall, 4^ miles south-south-west from 
Ipswich and nearly 10 miles from the nearest of the other sections; 
but the pits opened in it are now overgrown. Mr. Charlesworth,t 
in 1835, speaks of the Coralline Crag as exposed for about 
70 yards. Its thickness was 6 feet, and in attempting to dig 
through it work was stopped by the appearance of water at the 
further depth of 2 feet Lyell,J writing in 1839, says that he 
caused a pit about 7 feet deep to be sunk in the yard at Tatting¬ 
stone Hall Farm, piercing the lowest part there exposed of the 
Coralline Crag, through green marls, with intervening layers of 
flaggy limestone, two or three inches thicks At the bottom of 
this pit I found marl of the same character, containing a large 
Nucula, Venus ovata^ and some other shells ; when the workmen 
were stopped by the quantity of water which flowed in. One of 
the flaggy beds of limestone was almost of a brick-red colour, and 
consisted chiefly of comminuted shells, like the green marl,’* 
Mr. Whitaker § saw the Coralline Crag in 1877, and describes it 
as evenly bedded, firm, made up of finely broken shells, mostly 
buffi, hardened into stony lumps in discontinuous layers; about 
5 feet, but has been deeper.” He also speaks of the outcrop as 
little more than a quarter of a mile along the bottom of the valley 
from north to south, and only an eighth of a mile wide at most. 
It is bounded westward by the narrow alluvium, on the other side 
of which London Clay crops out, and elsewhere by Red Crag, 
which comes on above, and the underground extent of the older 
Crag is probably small.” Prof. Prestwich’s illustration of the 
* J-wre. iVa^. ser. 3, vol. xiii.p. 203. 1864. The observation was, I believe, 
inserted by S. V. Wood, jun., on the authority of Mr. Acton, 
t Phil. Mag., ser. 3, vol. vii. p. 84. (1835.) 
j Mag. Nat. Hist., ser. 2, vol. hi. pp. 314, 315. (1839.) 
§ Ipswich, Hadleigh, and Felixstow(AfmozVs of the Geol. Survey')^ p. 27. (1885.) 
