EVIDENCE FROM PALAEONTOLOGY 87 



is essential to a comprehension of the huge mass of 

 facts which have already been gathered. It is further 

 possible to make an approximate determination of 

 the relative chronology of the rocks and fossils in 

 different regions and continents, a determination 

 which is of the utmost importance, as will appear 

 later. In the following sketch of palseontological 

 evidence, it is not practicable to avoid all mention of 

 the technical terms used in designating the divisions 

 of geological time and so a table of these terms is 

 appended. 



Cenozoic era 



Mesozoic era 



Permian period 



Carboniferous period 



Devonian period 

 Palaeozoic era 1 Silurian period 



Ordovician period 

 [ Cambrian period 

 Pre-Cambrian eras. 



N. B. The arrangement of the table is such that the most ancient 

 times are at the bottom and the latest at the top; the epochs of the 

 Mesozoic and Palaeozoic eras are omitted as unnecessary. 



If, neglecting all details, we survey the great and 

 ever-changing procession of life, as it is recorded in 



