83

“The long lines of wasting cliff on the eastward-facing shore
present excellent sections of the deposits of which this low land
is composed, and these appear with scarcely any exception to
be those of the glacial or even yet more modern periods.

A few miles north of Lawn point, at the entrance to Skide-
gate, the most southern exposure is found in a low cliff or bank,
in which deposits evidently of glacial age are cut off above by a
gently undulating surface of denudation, and overlain by ten or
fifteen feet of superficial material which shows no sign of blending
with that below. The upper deposit consists of sand and well
rounded gravel, in regular and often nearly horizontal layers.
It has become in places quite hard, being apparently cemented
with ferruginous matter. Its lower layers hold some small
boulders, a few of which measure eighteen inches or two feet in
diameter. The lower deposit at the north end of the exposure—
which may be in all about two hundred yards in length— is a
typical boulder clay, with many half-rounded and subangular
stones and occasional boulders of some size. The matrix is
bluish-grey, hard and somewhat arenaceous. The whole is
irregularly mingled, and shows no sign of bedding. The boulders
were not observed to be striated, but smaller stones now loose
on the beach were so. Among the fragments pieces of lignite
from the Tertiary formation, which there is good reason to believe
underlies all this region, are quite abundant. When followed a
few yards southward this boulder clay begins to show bedding
and to become interstratified with hard clayey gravels composed
of well-rounded pebbles. The bedding of these is undulating
and rather irregular, and there is, as may be supposed, some local
unconformity by erosion between the different layers. A few
paces further on these become interbedded with, and are even-
tually replaced by, hard bluish-grey arenaceous clays, which hold
only occasional pebbly layers, but contain in abundance imper-
fect and broken specimens of several species of molluscs, among
which Leda fossa is the most common. A small Cardium-like
shell and fragments of a Balanus were also observed, but all
broken, and tender from partial decomposition.

In general appearance with their relation to the sea level,
and the shells found in them, these beds resemble very closely

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