part only in the next parish. A man in his development runs for a little
while parallel with, though never passing through, the form of the meanest
worm, then travels for a space beside the fish, then journeys along with
the bird and the reptile for his fellow travellers: and only at last, after
a brief companionship with the highest of the four-footed and four-handed
world, rises into the dignity of pure manhood. No competent thinker of the
present day dreams of explaining these indubitable facts by the notion of
the existence of unknown and undiscoverable adaptations to purpose. And we
would remind those who, ignorant of the facts, must be moved by authority,
that no one has asserted the incompetence of the doctrine of final causes,
in its application to physiology and anatomy, more strongly than our own
eminent anatomist, Professor Owen, who, speaking of such cases, says ("On
the Nature of Limbs," pp. 39, 40)--"I think it will be obvious that the
principle of final adaptations fails to satisfy all the conditions of the
problem."

But, if the doctrine of final causes will not help us to comprehend
the anomalies of living structure, the principle of adaptation must
surely lead us to understand why certain living beings are found in
certain regions of the world and not in others. The Palm, as we know,
will not grow in our climate, nor the Oak in Greenland. The white bear
cannot live where the tiger thrives, nor _vice versa_, and the more
the natural habits of animal and vegetable species are examined, the
more do they seem, on the whole, limited to particular provinces. But
when we look into the facts established by the study of the
geographical distribution of animals and plants it seems utterly
hopeless to attempt to understand the strange and apparently
capricious relations which they exhibit. One would be inclined to
suppose _a priori_ that every country must be naturally peopled by
those animals that are fittest to live and thrive in it. And yet how,