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the explorer has not the advantage of profiting by their exist- 
ence, where food is scarcest. The boars are sometimes very 
large, covered with long black bristles, and have enormous 
tusks, resembling closely the wild boar of the Ardennes, and 
they are equally savage and courageous. 
“Another interesting fact, is the appearance of the Norwegian 
rat. It has thoroughly extirpated the native rat, and is to be 
found everywhere, even in the very heart of the Alps, growing to a 
very large size. The European mouse follows it closely, and, what 
is more surprising, where it makes its appearance, it drives, in a 
great degree, the Norway rat away. Amongst other quadrupeds, 
cattle, dogs, and cats are found in a wild state, but not abundantly. 
“The European house-fly is another importation. When it 
arrives, it repels the blue-bottle of New Zealand, which seems 
to shun its company. But the spread of the European insect 
goes on very slowly, so that settlers, knowing its utility, have 
carried it in boxes and bottles to their new inland stations.” 
But the most remarkable fact of all has been communicated 
to me since the above was printed, viz., that the little white 
clover, and other herbs, are actually strangling and killing out- 
right the New Zealand flax ( Phormium tenax), a plant of the 
coarsest, hardest, and toughest description, that forms huge 
matt ed patches of woody rhizomes, which send up tufts of sword-like 
leaves, six to ten feet high, and inconceivably strong in texture 
and fibre. I know of no English plant to which the New Zea- 
land flax can be likened, so as to give any idea of its robust consti- 
stitution and habit, to those who do not know it ; in some 
respects the great matted tussocks of Carex paniculata approach 
it. It is difficult enough to imagine the possibility of white 
clover invading our bogs, and smothering the tussocks of this 
Carex, but this would be child’s play in comparison with the 
resistance the Phormium would seem to offer. 
The causes of this prepotency of the European weeds are pro- 
bably many and complicated ; one very powerful one is the 
nature of the New Zealand climate, which favours the duration 
of life in individuals, and hence gives both perennials and 
annuals a lengthened growing season, and, in the case of some, 
more than one seed crop in the year. This is seen in the 
tendency of mignionette and annual stocks to become biennial 
and even perennial, in the indigenous form of Cardamine hir- 
suta being perennial, and in the fact that many weeds that seed 
but once with us, seed during a greater part of the year in New 
Zealand. Another cause must be sought in the fact, that more 
of their seeds escape the ravages of birds and insects in New 
Zealand than in England; the granivorous birds and insects 
that follow cultivation not having been transported to the 
Antipodes with the weeds, or, at least, not in proportionate 
numbers. 
