CHAPTER VII 
SOME INTERESTING BRITISH PLANT GROUPS 
In the preceding chapters glimpses have been obtained 
of some of the wider aspects of plant life, particularly 
as seen on the hills and plains of our own country. 
The species composing our flora have been seen 
mostly, not as individuals, but as portions of regiments 
and armies, particular plants being mentioned but 
seldom, where required for purposes of illustration. 
In the final chapter it will be well to abandon this 
collective treatment, and glance at a few individual 
species or genera or small natural groups which 
possess features of interest of one sort or another. 
No systematic arrangement need be attempted: it 
will be pleasanter to ramble on, allowing our points of 
inguiry to turn up as they might on a country walk. 
A consideration of abnormalities in the manner in 
which plants obtain their food-supply—irregular 
nutrition, as it has been called—will raise some inter- 
esting questions, and will bring us up against some of 
the most remarkable species which are found in the 
British flora. The outlines of the method by which 
plants manufacture their food are familiar to all, and 
have been referred to already (pp. 75, 132). The roots 
absorb from the soil water containing dissolved salts, 
which is passed up by the stems into the leaves. The 
leaves extract from the air carbon dioxide. The 
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