THE TERM “ PLANT-COMMUNITY.” 15 
looked upon as living organisms with special forms more or less 
suited to the circumstances under which they live. Swamps, forests, 
bogs, and grassland, as will shortly be explained, are examples of 
distinct kinds of vegetation, and some of the units of such are the 
tussocks, the trees, and the shrubs. For the names and genetic 
relationship of these in the first instance a flora must be consulted. 
It is from a study of vegetation and its components rather than 
from floristic investigations that the story of a plant may be gathered. 
Those striking features of the landscape which stamp our country 
as New Zealand—swamps, forests, grassland, bracken-clad_ slopes, 
and manuka thickets—impress upon one the fact that the plants 
do not grow haphazard, but that some combination of conditions 
allows only definite sets of plants to occupy definite stations. These 
combinations of plants are called plant-communities—a comparison, 
but not very close, with human communities. Many plant- 
communities are less easy to recognize than are the swamps, 
forests, and so on—their delimiting requiring close observation 
combined with special knowledge and experience. 
A student investigating the vegetation of a fairly large area 
will soon perceive that plant-communities are not all of one kind. 
Unfortunately, there is as yet no recognized consensus of scientific 
opinion as to how they should be classified or what the names of 
the classes should be. In this book the conception of Professor 
Warming, as expressed in his “‘ Oecology of Plants,” is, with some 
modification, followed. The method to be adopted is, however, of 
no great moment, as long as the terms proposed are used with a 
definite meaning, so that their signification can be clearly understood. 
Taking the case of New Zealand, it has been found that those 
specially common botanical features of the landscape, the forest for 
both Islands, and the tussock-grassland for the South Island, when 
examined by one who knows the names or appearance of a majority 
-of the plants, differ considerably in their constituent members accord- 
ing to the latitude or altitude above sea-level of the plant-community 
‘n question. In other words, though the general appearance of a piece 
of either plant-community may be almost the same everywhere, it is 
the result of different combinations of species which, however much 
they differ in their relationship, are, when in combination, similar in 
outward aspect to those of other parts of the community, no matter 
where they may be situated. The forest of northern Auckland and 
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