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deposit of sandy beds and clay, similar to that below, as 
well as some that is brown and quite like the ordinary boulder 
clay of the district, except in containing shells. Over this 
were sand and clay, and occasionally pure decomposed chalk, 
and then a mass of boulder clay of the usual description. 
The lower part of the section is much contorted, in the 
manner so common in the drift strata, as described in my 
paper on that subject, published in the Report of this 
Society for 1851, p. 220, and there attributed by me to 
the action of icebergs. It is also well worthy of remark 
that the same force which produced these contortions appears 
to have fractured some of the shells imbedded in the clay 
and displaced the fragments, which, nevertheless, may often 
be found within a short distance of each other. I have in 
my collection a number of specimens of Saxicava rugosa 
that show this fact to great advantage. Indeed, it seemed 
as though the exposed crag was only the upper portions of 
the contortions, and that the main bed was below the level 
of the beach, and might not have been exposed in the cliff 
if it had not been thus bent and raised up by lateral pressure. 
Some of the beds of the crag, as well as of the boulder 
clay, contain a considerable amount of carbonate of lime, 
which may be seen with the microscope to be due to the 
presence of decomposed chalk, the minute granules of it 
being often most easily recognisable by their peculiar form. 
If the clay in which the fossil shells occur be washed in 
a fine sieve, the sandy material obtained contains many 
Foraminiferae and Entomostraca, that may easily be picked 
out with a small wet camel's hair brush. By washing and 
sieving the sandy bed, and then, when dry, shaking it, the 
small shells, being lighter^ rise to the surface, and I found 
in it some differing from those that I met with in the washed 
clay. Above a dozen species thus procured, which vary 
in size from one-tenth to one-fiftieth of an inch, have been 
