6 THE DARWINIAN HYPOTHESIS : i 
and only at last, after a brief companionship witn 
the highest of the four-footed and four-handed 
world, rises into the dignity of puremanhood. 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 incom- 
petence 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)—«TI 
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 versd, 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 
~~ Te) i) 
