204 THE COAST-FLORA OF THE CLACTON DISTRICT.
On the outer edge of the dune, just above the high-water mark,
sometimes on the shingly storm-beach, occurs Cakile maritima
(sea-rocket), a succulent annual Crucifer with bright red flowers.
In similar places, though generally less exposed, the prickly Salsola
kali (Saltwort) may be found, which is also an annual species.
This latter, however, is not a genuine Halophyte, having pene-
trated into the interior of the continent of America and there
become a pestilent weed in the corn-fields. Then comes a
region where grasses are dominant : Triticum junceum, whose
leaves are frequently seen to be reduced to almost hair-like
shape, extremely dwarfed forms (not more than a foot in height)
of Arundo Phragmites (Common Reed) alternate with Carex
arenaria (Sand-Sedge) and Festuca ovina var. sabulicola (?)
(Sheep's Fescue). On the lee-ward edge of the dune Atriplex
babingtonii (Frosted Sea-Orach), whose protection against drought
is afforded by a coating of scaly meal, becomes dominant. An
occasional Beta maritima (Sea Beet) may occur in this con-
nection. Both near Stone Point, at Walton, and on Colne Point
near St. Osyth Suaeda fruticosa (Shrubby Sea-blite) forms a
kind of littoral bush-land, it being the only plant on the Clacton
shore with lignified stem. Above the reach of the highest tides
occurs Artemisia maritima (Sea-Wormwood) protected by a
dense hairy cover. There appear to be two growth forms, one
stout and erect, the other rather drooping, the former growing
on the exposed edge, the latter on the more protected, though
less saline, lee-side of the sea-wall. In shallow depressions
just behind the dune, which are filled with salt-water, Salicornia
and Suaeda maritima (Sea-blite) become dominant. These pools
are generally fringed by a zone of Atriplex portulacoides (Sea
Purslane), like A. babingtonii, covered with a white scaly meal.
I have already alluded to the fact that its leaves assume a profil-
lie and have become isolateral in consequence.
The bulk of the vegetation of the sandy shore is, however,
not Halophilous. The plants grow on the coast, not because
they have a liking for salt, but because they find on the dune
the soil they most require, and have learnt to put up with the
salt as an addition that does no more than accentuate the already
strongly Xerophytic character of their station.
There is a pretty sharp division into two associations :—
(I.) The vegetation of the open, white dune, with the shift-
ing sand;