THE COAST-FLORA OF THE CLACTON DISTRICT. 20 J 
3. The ordinary level of the marsh or “ saltings.” 
4. The higher littoral meadow. 
In zone (2) Salicornia (in very succulent and richly ramified 
forms) and Spartina siricta (Bristle-grass) are the dominant 
species. Of common occurrence, especially in the more sheltered 
creeks, is Aster tripolium (Sea Aster). Spartina , a stiff, erect 
gregarious grass, advances furthest against the tide, forming low 
elevations in the soil of the open beach or fortifying the exposed 
bank of some creek. All the three species mentioned are 
excellent defenders of the land against the encroachment of 
the sea, and in many places they are agents in adding to the 
land. 
The sea-water rushes into the littoral marsh by a kind of 
inverse river-system, formed jointly by the backwash of the 
tide and the rain water. The vegetation of the level of the 
marsh varies considerably with its height. If it is low enough 
to be daily submerged in the tide, as it is the case with the 
Walton and Brightlingsea marshes, Poa maritima (the Glyceria 
or Sclerochloa of others) covers the soil with a dense tuft of its 
decumbent and floating stems. But sometimes the level is 
higher and only occasionally submerged. Then the vegetation 
is like that of the grey dune, characterised by its lowness, which 
dwarfing may be accounted for by drought, aggravated by a high 
degree of salinity and the exposure to wind : Salicornia her- 
bacea, Suceda maritima , Statice limonium (Sea Lavender), Aster 
tripolium, Inula crithmoides (Golden Samphire), Spergularia 
media (Sand Spurry). A very slight rise of the level gives origin 
to the growth of Alriplex portulaco'ides (Sea Purslane), whose 
silvery grey leafage fringes very prettily shallow stretches of 
Salicornia and Suceda. In autumn, when the latter turn deep 
red or rich purple, a brilliant picturesque effect rewards the 
botanist who visits the marshes in that season. 
The next zone is the least stable and the least defined. Lying 
at a level perhaps only a few inches above the former, flooding 
by the tide occurs still more rarely. There are several tracts 
of land on the Clacton coast which represent this zone. In 
ditches and muddy hollows occur Salicornia, Aster, Triglochin 
maritimum (.Sea Arrow-grass). But then follow large patches 
of land occupied by Scirpus maritimus and Juncus compressus , 
both gregarious and excluding nearly all other plants, where 
