Reconquest of the Water 
But to be quite frank about this subject, the reader 
ought first to spend six months in careful microscopic 
examination of all the alge and diatoms to be found 
in all the ponds and rivers in his district, then he should 
try to describe them, preferably in dithyrambs or 
leonine verses and not in plain prose. 
On the shores of many of our fresh-water lakes and 
tarns one finds occasionally another very curious and 
unusual flora. The plants are submerged and consist 
of tiny leaf rosettes which are exceedingly like one 
another except when in flower, although as different 
botanically as they well could be. There are species 
of Litorella (Plantaginacez), Lobelia Dortmanni, Subu- 
laria (Cruciferz), Isoetes, Heleocharis acicularis, &c.* 
These little rosettes of linear leaves are generally 
planted amongst stones, which as well as themselves are 
covered over with the usual golden-brown diatom crust, 
or with entangled webs of algz. 
It is said that it is specially where the waves are 
strong, and perhaps where the ice grinds along the 
shore in winter, that this Litorella association replaces 
reeds and marsh plants. 
Along many of our Scotch rivers also, a very inter- 
esting process can be followed. The river flows 
between banks some 7 to ro feet high, which it 
has cut out of its flood plain. At the foot of these 
banks, certain plants are always trying to establish 
themselves, and especially where the water is shallow. 
The most prominent is Phalaris arundinacea, a grass 
whose tough rhizomes are tied down amongst the 
stones by strong anchoring roots. This grass is very 
important to the neighbouring proprietors, whose land is 
being saved by it from the constant encroachments of 
the current when in flood. 
* Vallisneria, which is not British, is extremely similar. 
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