Geographical Distribution. 213 
faunas and floras of the world, so that merely to 
enumerate the instances would require a separate 
chapter. 
Furthermore, the general argument thus presented 
in favour’ of descent with continuous modification 
adinits of being enormously strengthened by three 
different classes of additional facts. 
The first is, that the correlation in question— 
namely, that between a geographically restricted 
habitat and the zoological or botanical affinities of 
its inhabitants—is not limited to the now existing 
species, but extends also to the extinct. That is to 
say, the dead species are allied to the living species, 
as we should expect that they must be, if the latter 
are modified descendants of the former. On the 
alternative theory, however, we have to suppose that 
the policy of maintaining a correlation between geo- 
graphical restriction and natural affinity extends very 
much further back than even the existing species 
of plants and animals; indeed we must suppose that 
a practically infinite number of additional acts of 
separate creation were governed by the same policy, 
in the case of long lines of species long since extinct. 
Thus far, then, the only answer which an advocate 
of special creation can adduce is, that for some reason 
unknown to us such a policy may have been more wise 
than it appears: it may have served some inscrutable 
purpose that allied products of distinct acts of crea- 
tion should all be kept together on the same areas. 
Well, in answer to this unjustifiable appeal to the 
argument from ignorance, I will adduce the second 
of the three considerations. This is, that in cases 
where the geogiaphical areas are not testricted the 
