438 ELEMENTARY GEOLOGY 
The crowning feature of the progress of life upon 
the globe, was the coming of man. How he came, by 
what ancestry, or by what means, it is impossible at 
present to say, nor can we state when he came. It is 
certain that man has lived upon the earth many thou- 
Ideal landscape of Cretaceous period. (After Haushofer.) 
sands of years; and it is probable that his time of life 
is to be numbered in scores of thousands of years. 
There is good evidence that he lived as a contemporary 
of the glacial period, which involved northern Hurope 
and America in an ice sheet, certainly many thousands 
of years ago. He also lived in association with types 
