i6 BRITISH MAMMALS 



EPOCHS 

 SECONDARY 



Period — Triassic (The beast-like Reptiles, A?tomodontla, begin to appear. 

 Mammals of a low, indeterminate, Monotreme type 

 make their appearance in Europe and North America.) 

 „ Jurassic (Birds originate from reptiles at the beginning of this period.) 

 ,, Cretaceous (The " Chalk " ages. Forms related to the Marsupial 

 or Metatherian Order of Mammals make their 

 appearance ; and perhaps at the close of this period 

 the first types of Eutherian orders — Insectivores, 

 Creodonts, Early Primates, and Ungulates — are 

 evolved. This is the great age of reptiles.) 



TERTIARY 



,, Eocene ("Dawn of recent times." Most of the known orders 

 [Oligocene] of Mammalia accomplish their definite differentiation 

 during this first period of the Tertiary Epoch.) 



,, Miocene (" More recent." Most of sh.^ families of the Mammalia 

 are developed during the Miocene. The flora and 

 fauna of England at this time suggest affinities with 

 tropical Asia and Africa.) 



,, Pliocene ("Still more recent." The modern genera are now 

 developed. The fauna of England and Wales at 

 this time recalls that of modern India, Malaysia, or 

 Africa. Man orig inates during this period in South- 

 eastern Asia, and spreads westwards towards Britain.) 



„ Pleistocene (" Most recent." During this period many modern 

 species are differentiated. Man becomes established 

 in England, Scotland, and Ireland, and elsewhere 

 all over the world. In the early part of the 

 Pleistocene the mammalian fauna of England and 

 Wales is that of Northern Africa, the Mediterranean, 

 and North Indian regions, gradually changing to a 

 Boreal (Siberian, North American) character, as the 

 icy ages, the Glacial sub-periods, supervene in the 

 British Isles and in much of Northern and North- 

 western Europe.) 



QUATERNARY 



„ Prehistoric (The age of Neolithic man ; of the origin of our 

 domestic beasts ; and of most varieties and sub- 

 species of existing mammals.) 



„ Recent (From the rise of human history, about eight thousand 

 years ago, to the present time.) 



