THE MAMMALS, REPTILES, AND
FISHES OF ESSEX.
INTRODUCTION.
ESSEX, the tenth English county in point of
size, contains an area of some 987,623
acres. It is of irregular shape, and measures sixty-
three miles in length, from S.W. to N.E. On
the south, it is bounded by the Thames; on the
north, by the river Stour; the rivers Lea and Stort
divide it on the west from Hertfordshire; and
its eastern limit is the North Sea.
The sea-board of the county is deeply indented
by the four large estuaries of the rivers Thames,
Crouch, Blackwater and Stour, upon the shores of
which, as on the intervening sea-line, a wide margin
of marsh occurs, more or less broken into low-lying
islands and tracts connected with the mainland.
The shores of this marshy district consist of long
stretches of sand or mud, exposed at low water, and
intersected by creeks, many of them also dry at low