Seasides and Strand Plants 
Most of these plants have smooth, more or less suc- 
culent leaves, for like Salicornia they have to endure 
from .o4 to nearly 5 per cent. of salt water. Now 
several experimenters have directly produced fleshy 
leaves, quite of this character, by supplying, for instance, 
garden wallflowers with salt instead of fresh water.® 
So that this fleshiness seems to be a fitting reaction 
caused by the salt, and also helping the plant to resist its 
poisonous effect by living in a thirsty sort of way. 
Such Armeria flats vary considerably. On the Clyde 
one may find exquisite dark green mats of: the Alga 
Vaucheria filling up the interstices between the other 
plants, and firmly attached to the dark mud by hundreds 
of rhizoids. The elastic strength of such a Vaucheria 
cushion is very remarkable, as one can see by cutting 
out a square foot and holding it up by onecorner. Such 
fat, dark soil as one finds along the Clyde is probably 
full of organic matter, but it is kept well aerated by 
various small worms. There may be as many as 
fifteen of their burrows in a square inch of surface. 
Cattle and sheep browse at low tide upon the 
Armeria flats, where indeed they grow fat and flourish 
exceedingly. 
But on the landward side, where the salt is being 
gradually drained out, and where the level of the soil 
has so much increased in height that even the highest 
tides but rarely extend to it, a new process is beginning. 
Rushes (J. lamprocarpus), sedges, and a few grasses 
(Agrostis, Festuca alba var. stolonifera) are beginning to 
encroach upon the Armeria country, and if they once suc- 
ceed in getting a root-hold, other weeds come in (couch- 
grass, cock’s-foot, Yorkshire fog, bird’s-foot trefoil, white 
clover, silverweed, and Crepis virens), and it is soon a 
seaside meadow. It is difficult to trace the later stages, 
for by the time that some of these weeds have effected 
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