1/2 EVOLUTION OF TO-DAY. 



which is radically separated from those of the other. 

 And South American fossil monkeys are similar to 

 the present animals found there ; while the fossils 

 of Europe are closely related to the order of Old- 

 World monkeys now existing. Perhaps the best 

 illustration of this principle is afforded by Australia. 

 This strange land has no mammals except marsupi- 

 als, and, as we come to study the fossils of the 

 country, we find that they in like manner comprise 

 numerous marsupials, but no other mammals, and 

 these marsupial fossils are of such a structure as to 

 show a close relation to existing species. It cannot, 

 of course, be claimed that the present species were 

 created so closely related to the older inhabitants, 

 because the climate of Australia is especially 

 adapted to this form of animal ; for, as we have 

 already noticed, almost every European mammal is 

 able, not only to exist in Australia, but also to ex- 

 terminate the native inhabitants. But geology 

 readily explains this peculiar fauna. Australia was 

 formerly connected with Asia at a time when the 

 latter continent was filled with marsupials. But the 

 connection was soon lost, and when higher mammals 

 appeared in Europe and Asia they were unable to 

 get into the now separated Australia. The marsu- 

 pials which this land had originally received from 

 the north, had the whole continent to themselves, 

 and they therefore multiplied and expanded, giv- 

 ing rise to the present marsupial fauna, unmolested 

 by any of the higher mammals which were develop- 

 ing on the other continents. And numerous other 

 instances could be given, showing conclusively that 



