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Species and other Controversial Points. 
individual cases, being apparently of no effect when dealing with many allied 
species. This law, once stated, has evidently to be hedged round with 
various provisos, indicating the various causes which may modify its action. 
One, for example, which seemed to me so obvious that I did not mention it 
specifically, was that the law would only be strictly operative so long as the 
conditions remained constant — a change of climate or submergence of part 
of the country would clearly modify its operation. 
‘ So long as the law was only based upon the estimates given for 
distribution in Ceylon, so long was its foundation somewhat precarious, and 
as soon as possible I worked out another flora, that of New Zealand, but 
with actual distances of spread instead of estimates. This gave confirmatory 
evidence of the most satisfactory kind, the graduation of the endemic species 
from few of large spread down to many of small, and of the wides in the 
opposite direction, being very clearly shown, while at the same time the 
prediction which I made, that if New Zealand were divided into equal zones 
the endemic species would appear in them in numbers graduated up to 
a maximum (or sometimes two), was borne out by the facts in the most 
convincing manner, leaving no room for doubt that Natural Selection could 
not be the operative factor in causing their distribution. 
f That the longer a species has been in a country, the more area it should 
occupy, does not seem to be an unreasonable nor far-fetched explanation, but 
it leaves out of account the structural differences between species, and ignores 
Natural Selection, and thus runs much against the grain to many botanists, 
who still base their arguments (though often more or less unconsciously) upon 
it. In particular they have long been accustomed to look upon the endemic 
species of small areas as being the oldest in a country, instead of the youngest, 
and as being in some way expressly suited to the local conditions, though 
when pressed they are not able to suggest any very clear reason for their belief. 
There is nothing in the structure of most endemic plants to show that they 
are in any way adapted to local conditions, nor that they are any older than 
the species of wider distribution that accompany them, though not seldom 
something to show the contrary. 
‘ The essential facts which have to be explained in the floras of Ceylon 
and New Zealand (and observation on other floras shows that they are very 
general x ) are that the endemic and the widely distributed species in a given 
country are arranged in graduated series, showing an increase in number in 
opposite directions, the endemics increasing from those of wide to those of 
narrow distribution, the wides in the other direction. I have already shown 
that Natural Selection cannot account for such regular arrangement of 
distribution, which shows not only on the total, but also family by family. 
1 The case of England, or of other countries which have been completely altered by man, must 
be dealt with separately. The advent of man may soon become as important as a geological 
catastrophe or a serious change of climate- 
