0'Ekilt.y— 0>? the Wade of the Coast of Ireland, 8fc. 99 



^appears on the stage, and to see how they are related to the vaiying 



conditions of life on the Continent." 



He then gives the following classification of the stages of the 



Tertiary Period : — 



Characteristics. 



I. Eocene ; or that in which the Mammalia now on the ) y ■ • j ■, 



Earth were represented bv allied forms belonginer to > V^°-, . ^ ^^ ^" 

 ■ ■■ J J J? -v D o J tamilies present, 



existing orders and iamilies. ; ^ 



II. Miocene ; in which the alliance between living and ) t • • 



fossil mammals is more close than before. / & S <*• 



III. Pliocene ; in which living species of animals appear. Living species. 



IV. Pleistocene ; in which living species are more abundant ) Living species abun- 

 than the extinct. Man appears. ) dant. Man appears. 



V. Prehistoric ; in which domestic animals and cultivated i Man abundant. Do- 

 fniits appear, and man has multiplied exceedingly > mestic animals, 

 on the Earth. J Cultivated fruits. 



VI. Historic ; in which the events are recorded in history. Historical record. 



(p. 14.) — He says : " The invasion of Europe by the Placental 

 Mammals is the great event which is the natui'al starting-point for our 

 inquiry into the ancient history of man, since the conditions by which 

 he was surrounded on his arrival in Europe form part of a continuous 

 sequence of changes from that remote period down to the present day." 



(p. 18.) — He gives a sketch map (fig. 3) of the geography of north- 

 western Europe in the Eocene Age, and having given the reasons which 

 enabled him to give its outline he says : 



(p. 23.) — "From these considerations (zoological, botanical, and 

 geological). Eocene Britain (and Ireland) may be taken to have foimed 

 part of a great continent extending north and west to America by way 

 of Iceland and Greenland, while to the north-east it was continuous 

 with Norway and Spitzbergen. It extended also to the south-west 

 across what is now the Channel to join the western parts of France. 

 This great north-western continent or ' Northern Atlantis ' as it may 

 be termed, existed through the Eocene and Miocene Ages, offering a 

 means of free migration for plants and animals, and it was not finally 

 broken up by submergence until the beginning of the Pleistocene Age." 



(p. 43.) — As regards the continuity with North America he states : 

 "The researches of Professor Heer into the forest vegetation of the 

 Continent, Britain, Iceland, Spitzbergen, Greenland, and Grinnell- 

 land prove that the whole of this portion of the Earth's siu'face was 

 diy land in the early Tertiary Period, offering free means of migration 

 to plants and animals from the Polar regions into America on the one 



