224 VIGNETTES FROM NATURE. 



southern extremities. Hence, generally 

 speaking, we may expect to find the newest 

 and most modern types in the great northern 

 continents, and the oldest and most archaic 

 types in the tapering southern peninsulas and 

 islands. 



The fact is, however, it is now autumn 

 with the whole of our planet, and the last 

 great cold spell from which the northern 

 hemisphere suffered — the glacial epoch — has 

 somewhat interfered with the literal truth of 

 this rough generalisation. Climatically speak- 

 ing, our earth has seen its best days. We 

 are now growing colder from age to age, and 

 we may look forward in the distant future to 

 an absolute winter extending over the whole 

 globe, when its surface will be as dead and 

 changeless as that of the moon actually is 

 before our own eyes. Life, indeed, viewed 

 cosmically, is but a superficial phenomenon 

 produced by arrested solar radiation on the 

 outer crust of a cooling nebula, and it will 

 disappear some day, from this earth at least, 



