45 THE NO A CHI AN FLOOD. 



continent from those of another 1 . The marsupials of 

 Australia and Polynesia are generically distinct from all 

 other animals on the globe except the opossum. The 

 elephant of Africa is not the same species as the elephant 

 of India : so with the lion, so with the rhinoceros. The 

 apes and bahoons of the old world are nowhere to be 

 found in America, nor the American monkeys anywhere 

 in the old world. In Madagascar, separated from Africa 

 by less than the breadth of England, all the species ex- 

 cept one, and nearly all the genera, are peculiar 2 . Every- 

 where species are found limited in their range by natural 

 barriers, such as climate, rivers, mountains, oceans. Are 

 we to suppose that the prisoners could scramble into 

 their prisons, and then suddenly became incapable of 

 scrambling out again ? Everywhere, as a rule, this 

 range is consistent with the hypothesis of an origin 

 central to the range, inconsistent with that of an origin 

 distant from it. Where, as on mountain ranges, we find, 

 contrary to the general rule, the same species in differ- 

 ent localities, the migration from the door of the ark 

 loses all semblance of probability, unless we are pleased 

 to imagine that creatures, now without the instinct of 

 migration, for a long time possessed it, and roamed 

 about the world through many a sultry plain to pick 

 out a hill-side here and there with a temperature suited 

 to their constitutions. But the exceptional phenome- 

 non, otherwise so hard to account for, Darwin has ad- 

 mirably explained, by pointing out that species adapted 



1 Lyell, 'Principles of Geology,' ii. 332. 2 Ibid. ii. 344. 



