Vice-Presidenfs Address. 185 



solidated. The Mesozoic lands were larger than those of the 

 preceding Palseozoic era, but they were still penetrated in 

 many places by the sea, and warm currents could make theii' 

 way over wide tracts that are now raised above the sea-level. 

 Under such circumstances, approximately uniform conditions 

 of climate could not but obtain. 



Great geographical changes supervened upon the close of 

 the Cretaceous period. North America then acquired nearly 

 its present outline. Its Mediterranean sea had vanished, but 

 the Gulf of Mexico still overflowed a considerably wider 

 region than now, while a narrow margin of the l^acific border 

 of the continent continued submerged. In Europe elevation 

 ensued, and the sea which had overspread so much of the 

 central and eastern portions of our continent disappeared. 

 Southern Europe, however, was still largely under water, 

 while bays and inlets extended northwards into what are 

 now the central reofions of the continent. On to the close 

 of the Miocene period, indeed, the southern and south- 

 eastern tracts of Europe were represented by straggling 

 islands. In middle Cainozoic times, the Alps, which had 

 hitherto been of small importance, w^ere considerably upheaved, 

 as were also the Pyrenees and the Carpathians ; and a 

 subsequent great elevation of the Alpine area was effected 

 after the Miocene period. Notwithstanding these gigantic 

 movements, the low-lying tracts of what is now Southern 

 Europe continued to be largely submerged, and even the 

 central regions of the Continent were now and again occupied 

 by broad lakes, which sometimes communicated with the 

 sea. After the elevation of the Miocene strata, these inland 

 seas disappeared, but the Mediterranean still overflowed 

 wider areas than it does to-day. Eventually, however, in late 

 Pliocene times, the bed of that sea experienced considerable 

 elevation ; and it was probably at or about this stage that 

 the Black Sea and the Sea of Azov retreated from the broad 

 low grounds of Southern Eussia, and that the inland seas and 

 lakes of Austria-Hungary finally vanished. 



The movements of upheaval, which caused the Cretaceous 

 seas to disappear from such broad areas of the continental 

 plateau, induced many changes in the floras and faunas of 



