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any geologist. 
THE MEANING OF EVOLUTION 
Most of them will serve to keep very 
clearly before the mind of the ungeological the period 
which he is studying. Like all such tables, this must 
be read from the bottom up. This arrangement is 
used because the oldest rocks in the series are natu- 
rally at the bottom and the newest rocks are on the 
top, though occasionally a region is sufficiently upset 
partly to reverse the order. 
TABLE OF GEOLOGICAL TIMES 
MILLIONS OF YEARS AGO 
STAGES OF ANIMAL 
ERAS 
(VERY UNCERTAIN) DEVELOPMENT 
Age of Man 
Recent Life ies (Quaternary) 
‘enozoic ge of Mammals 
(Cenozoic) 5 Age of Mammal 
(Tertiary) 
seats 5 to 10 Age of Reptiles 
Age of Amphibians 
(Carboniferous) 
Ancient Life ne DEBS 
(Palzonoic) 10 to 25 (Devonian) 
2 Age of Invertebrates 
(Silurian and Cam- 
brian) 
Dawn Life Earliest Animals and 
(Eozoic) 25 to 50 Plants 
Having seen what the scientist supposes to be the 
method of formation of the earth itself, it will be 
