4 THE ESSEX NATURALIST.
tion of minor geological processes. Root-action is an agency
that one is rather apt to overlook, yet it has much influence
in breaking down the stratification to a considerable depth,
according to the size and age of the trees.
In addition, when a tree is blown down it not only tears
up a hole in the ground, but the roots often form a sheltering
wall standing on one side of the hollow. Primitive man would
surely take advantage of such natural shelters and adapt
them to his use. When digging in the submerged "floor" I
have noticed places where the relics run down into hollows a
foot or two below the general level, and of a size that might
result from the blowing down of a big tree. These irregularities
make precise levels unreliable as evidence of relative date,
unless there be some independent evidence to support it.
Burrowing Animals: the Netteswell Cross Section.—
While man sets traps for burrowing animals they, in revenge,
are very busy setting traps for the Pickwicks of archaeology, as
their industry often disarranges the Stratigraphical order. On
the other hand, even the rabbits have on occasion done me
useful service and revealed finds of much interest.
The most striking and clearest illustration of disturbance
that I have ever seen was in connection with a badger earth
revealed in a pit at Netteswell Cross near Harlow; the pit
concerned being the first to the south-east of the four cross roads.
On the lower slopes of the valley side there is a considerable
accumulation of hill-wash, and Mr. A. Santer Kennard's
examination of the shells has shown that this is of several different
dates within the Holocene Period. One patch yielded Trochulus
cartusiana, which is quite extinct in Essex, and Pomatius
elegans, which is extinct locally. At another spot P. elegans
occurred in the upper part with Helix hortensis and H. arbustorum
at a lower level. In places frog bones occurred in vast numbers.
The main deposit of the pit consisted of laminated loams,
sands and marls overlaid by gravel in the higher part of the pit,
the whole belonging to the Glacial Period; while one big block
of very Chalky Boulder Clay thrust into the deposits caused
much contortion.
The Glacial deposits in the lower north-western corner of
the pit, but nowhere else in either this or other neighbouring