ANTARCTIC ADVENTURE AND RESEARCH 



This genus Glossopteris ranges from Upper Car- 

 boniferous to Rhaetic (Upper Triassic) period. Prob- 

 ably at Mount Buckley the beds are of Permo-Carbon- 

 iferous age just as they occur in the coal measures of 

 Australia. At the end of Carboniferous times, en- 

 vironments changed all over the world so that the old 

 Lepidodendron flora (of Lower Carboniferous days) 

 branched into two different types ; one without much 

 change in the Northern Provinces (Canada, Europe, 

 China) ; and the other developed into the southern 

 Glossopteris flora of India and the three southern con- 

 tinents. In most of these latter localities glacial de- 

 posits are commonly associated with the Glossopteris 

 ferns. Marked rings of growth occur in the trees of 

 Permo-Carboniferous times, indicating strong changes 

 in the seasons during the year. These are absent in the 

 Lepidodendron floras. Thus we are led to believe that 

 in the southern hemisphere and in India the configura- 

 tion of the land favored the growth of glaciers and 

 icebergs while in the northern province there were 

 extensive swamps and ice- free hills. Seward does not, 

 however, think that the paleobotanical evidence is fa- 

 vorable to a view involving an alteration in the position 

 of the earth's axis. But he inclines to a belief in an 

 Antarctic land on which were evolved the elements of 

 a new flora which spread in diverging lines over a 

 Paleozoic Continent (generally known as Gondwana- 

 land). 



Sir Edgeworth David has endeavored to estimate the 

 extent and possible value of the coal reserves in Ant- 

 arctica. The Beacon Sandstone is proved to cover 



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