212 



CHAPTER XT. 



FORMER VICISSITUDES IN CLIMATE — continued 



WARM CLIMATE IMPLIED BY THE FOSSILS OF THE CHALK — CRETACEOUS 



REPTILES HOW FAR EXTINCT GENERA AND ORDERS MAY ENABLE US TO 



INFER THE TEMPERATURE OF ANCIENT CLIMATES EVIDENCE OF FLOATING 



ICE IN THE SEA OF THE WHITE CHALK OF ENGLAND WARM CLIMATE OF 



THE OOLITIC AND TRIASSIC PERIODS— WIDE RANGE OF THE SAME FAUNA 

 FROM SOUTH TO NORTH ABUNDANCE AND W T IDE RANGE OF REPTILES IM- 

 PLIES A GENERAL ABSENCE OF SEVERE COLD — THE NON-EXISTENCE OF CON- 



MAMMALIA 



IN HIGH 



LATITUDES PERMIAN FOSSILS— SUPPOSED SIGNS OF ICE-ACTION 



IN THE PERMIAN PERIOD— UNIFORMITY OF THE FOSSIL FLORA OVER WIDE 

 AREAS— MELVILLE ISLAND COAL-PLANTS— HOW FAR THE ABSENCE OF FLOWER- 

 ING PLANTS VITIATES OUR INFERENCES AS TO ANCIENT CLIMATES 

 WHETHER THE ATMOSPHERE WAS SURCHARGED "WITH CARBONIC ACID IN 

 THE COAL PERIOD— FOSSIL SHELLS AND CORALS OF THE CARBONIFEROUS 

 STRATA— CLIMATE IMPLIED BY THE REPTILES OR AMPHIBIA OF THE COAL 

 DEVONIAN PERIOD, AND SUPPOSED SIGNS OF ICE-ACTION OF THAT ERA 

 CONSIDERED -CLIMATE OF THE SILURIAN PERIOD— CONCLUDING REMARKS 

 ON THE CLIMATES OF THE TERTIARY, SECONDARY, AND PRIMARY EPOCHS. 



In the last chapter I endeavoured to trace back the history 

 of the changes of climate from modern times to the Eocene 

 period, and we found, that before we had carried back our re- 

 trospect as far as the Newer Pliocene deposits, proofs already 

 presented themselves, both organic and inoi 

 perature much colder than that now prevailing in European 

 latitudes. Although this Glacial epoch, as it has been called, 

 lasted for thousands, if not hundreds of thousands of years, it 

 was of so modern a geological date as to belong almost exclu- 

 sively to the time when the shells were the same as those now 

 living. The geographical range only of species was different, 

 because an arctic fauna was enabled by aid of the cold to invade 



temperate 



examination 



Miocene 



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