CHAPTER III 



Life in Tertiary Times 



r T^HE rising up of the Pyrenean, Alpine, and Himalayan 

 ^ mountain chains gradually gave to the world its present 

 contours. The seasons became more marked. The torrid, 

 temperate, and frigid zones were on their way to their present 

 limits, though the polar regions were throughout favoured 

 with a temperate climate. Plants took on the forms in which 

 they still appear to-day. New Protozoa, the Nummulites 

 with lenticular shells, round like coins, invaded the seas in 

 such quantities that the first half of the Tertiary has been 

 called the " nummulitic period ". They make their first 

 appearance in the Pyrenees, Istria, and Egypt, in 

 layers where we still find a few survivors of the large 

 Mosasaurian and Dinosaurian Reptiles, whereas in these 

 same layers in Patagonia we see the oldest known placental 

 Mammals appearing for the first time and in considerable 

 numbers. 



At the opening of the Eogene, which corresponds to the 

 first half of the Tertiary, western Europe and North America 

 were joined by a strip of land which probably comprised 

 Scotland, Ireland, Cornwall, Brittany, the Central Plateau, 

 the Iberian Meseta, and the eastern coasts of North America, 

 and which was here and there broken up into archipelagoes. 

 From time to time communication between Europe and 

 America was sundered, notably in the middle of the Neogene, 

 and was again established for a time toward the end of the 

 same period, after which it was completely broken, and the 

 North-Atlantic continent was formed. 



The Sino-Siberian continent remained isolated. It was 

 probably the home of the even-toed Mammals which, on 

 several occasions, suddenly appeared in Europe during the 

 Lutetian and Ludian Periods, for Anoplotheriam already 

 existed in Asia at that time. The Afro-Brazilian continent 



