224 EVOLUTION IN BIOLOGY vi 



investigation were better calculated to inspire 

 distrust of the dogmas intruded upon science in 

 the name of theology, than those which relate to 

 the distribution of animals and plants on the 

 surface of the earth. Very skilful accommodation 

 was needful, if the limitation of sloths to South 

 America, and of the ornithorhynchus to Australia, 

 was to be reconciled with the literal interpretation 

 of the history of the deluge ; and with the estab- 

 lishment of the existence of distinct provinces of 

 distribution, any serious belief in the peopling of 

 the world by migration from Mount Ararat came 

 to an end. 



Under these circumstances, only one alternative 

 was left for those who denied the occurrence of 

 evolution namely, the supposition that the 

 characteristic animals and plants of each great 

 province were created as such, within the limits in 

 which we find them. And as the hypothesis of 

 " specific centres," thus formulated, was heterodox 

 from the theological point of view, and unintelli- 

 gible under its scientific aspect, it may be passed 

 over without further notice, as a phase of transi- 

 tion from the creational to the evolutional hypo- 

 thesis. 



8. In fact, the strongest and most conclusive 

 arguments in favour of evolution are those which 

 are based upon the facts of geographical, taken 

 in conjunction with those of geological, distri- 

 bution. 



