118 THE ESSEX NATURALIST.
showed this fourfold structure in the Bronze and Iron Ages
(Fig. 1).
Thus, the appearance of the county seen by these early
invaders would have shown a heavily forested tract passing
from the south-west of Essex across the landscape in a north-
easterly direction becoming more open as the chalkiness of the
Boulder. Clay increased, and probably changing to open park-
land on reaching the chalk country proper. This wide belt of
high forest must have covered the greater part of the county,
Fig. i. Vegetational Regions in Essex.
degenerating in the south-east to a lighter and more "leggy"
woodland growth on the broad stretch of coastal London Clay.
To either flank of this latter region the light soil belts would
have been visible by reason of their scrubby or open woodland
growth. The coast itself would have appeared as a wide marshy
tract threaded by a network of eastward flowing rivers.
The truth of this hypothesis may be vouched for by the
distribution of settlement sites belonging to those prehistoric
peoples known to have practised some form of agriculture.