CHAPTER Vlir. 



THE FIRST FORESTS OF MODERN TYPE. 



FOR a long time it was believed by geologists that a great 

 and mysterious gap separated the Upper Cretaceous 

 from the oldest Tertiary formations ; and in Western Europe, in 

 so far as physical conditions and animal life are concerned, the 

 severance seemed nearly complete. Oceanic deposits, like the 

 Upper Chalk, are succeeded by beds of littoral and estuarine 

 characters. The last and some of the greatest of the Me- 

 sozoic Saurians have their burial-places in the Upper Cre- 

 taceous, and appear no more on earth. The wonderful 

 shell-fishes of the Ammonite group, and the cuttle-fishes of 

 the Belemnite type, share the same fate. With the earliest 

 deposits of the Eocene Tertiary came in multitudes of large 

 Mammalia heretofore unknown, and the Cetaceans appear 

 in the sea instead of the great marine lizards ; while shells, 

 corals, and crustaceans of modern types swarm in the waters. 

 Thus it is true that a great and apparently somewhat abrupt 

 change takes place at the close of the Cretaceous, and ter- 

 minates for ever the reptilian age. Even in regions like 

 Western America, where physically the later Cretaceous 

 shades gradually into the earlier Tertiary, so that there have 

 been doubts as to the limits of these several periods, the 

 same great change in animal life occurs. 



But a link of connection has at length been found in the 

 history of the vegetable kingdom. The modern flora came 



