438 THE ECOLOGY OF PLANTS. 



Sea Rocket, Sea Spurge, Sea Holly, Sea Convolvulus, etc., and 

 further back come various plants which are not confined to 

 the seaside, but grow on stony places inland as well, e.g. Rest- 

 harrow, Gorse, Broom, Dyer's G-reenweed, Silverweed, Burnet 

 Rose, Carline Thistle. The Sea Bladder Campion is a charac- 

 teristic plant on most pebble beeches. 



415. Salt Marshes or mud-flats occur chiefly near the 

 mouths of rivers and along estuaries and creeks. Their vege- 

 tation is, on the whole, distinct from that of sand dunes, 

 though a few plants occur in both sand and salt mud, e.g. 

 Sea Milkwort, Sea Plantain, Thrift, Scurvy-grass, Saltwort. 

 Grass-wrack (Zostera) grows not only between the high 

 and low tide-marks, but often to a depth of thirty feet, form- 

 ing a green submarine meadow among the brown seaweeds 

 (Bladder- wrack, etc.), its matted rhizomes binding the silt 

 while its long leaves float in the water. The typical salt 

 marsh plants, however, grow where submerged only by high 

 tides, or a little above the high tide-mark. 



One of the most characteristic salt marsh plants, growing 

 just above high tides or partially submerged, then, is the 

 Marsh Samphire (Salicornia, with green or reddish cylin- 

 drical fleshy jointed stems, the leaves being reduced to small 

 opposite lobes at the joints where also the minute flowers are 

 produced). A little higher we usually find Sea Sweet- 

 grass (Glyceria maritima), Sea Arrowgrass (TriglocJiin 

 maritimum, with long narrow fleshy leaves in a rosette and 

 a long flowering- stem ending in a raceme of yellow-green 

 flowers), Sea Elite (Suaeda, allied to Saltwort but leaves 

 soft and fleshy and not spiny at the tip), Scurvy-grass, 

 Thrift, Sea Lavender (Statice, with creeping woody rhizome, 

 lanceolate leaves in a rosette, purple flowers in a curved 

 corymb), Salt Spurrey (Spergularia marina), Michaelmas 

 Daisy, Golden Samphire, Sea Plantain, Beet, Sea 

 Wormwood, etc. 



Some of the salt marsh plants extend a long way up 

 an estuary, often forming extensive reed- beds, the dominant 

 plant in which is frequently a variety of Bulrush (Scirpus 

 lacustris), and mingle with various marsh plants which can 

 stand a certain amount of brackish water, but are finally 

 replaced by the ordinary freshwater marsh plants. 



