34 PLANT ASSOCIATIONS 
help us to identify the association should we en- 
counter it again; there will be others—dependent 
species—which are attracted by the shade, or shelter, 
or other advantages which the growth of the domi- 
nant plants affords: and there will be others, again— 
probably many—of wide distribution, which are 
merely as much at home here as elsewhere. But all 
grow here because they are better fitted for the 
particular conditions prevailing than are the other 
plants of the surrounding area. On Farleton Fell, 
for instance, among the most abundant species 
which fill the crevices of the limestone plateau are 
two ferns—the Limestone Polypody (Polypodium 
Robertianum) and the Rigid Buckler Fern (Lastrea 
rigida). Though there is rocky ground of many 
kinds in the Lake District, these two plants are never 
found save on similar outcrops of the Carboniferous 
Limestone, and they are clearly specially fitted for 
life in the hollows of this rock. But the same rock 
crevices also harbour many species which are found 
equally on the soils derived from the slate rocks or 
sandstones. To take another instance: many of our 
most familiar spring flowers are woodland plants— 
the Primrose (Primula acaulis), Wood Anemone 
(A. nemorosa), Wild Hyacinth (Endymion non- 
scriptum). These rejoice in the humus soil which is 
formed from the dead leaves of preceding years; 
they flower before the trees are in full leaf, thus 
securing plenty of light and air for their period of 
growth; and they are accustomed to have their stems 
and roots protected from summer heat by the leafy 
canopy overhead. Transplanted into an adjoining 
sunny pasture they will soon die out. They are 
