1812 
president’s address. 
with outliers towards the west. From the characters of the 
Lepidodendron flora which then floiu’ished there, we conclude that 
the climate also was insular, — equable, moist and temperate, — at 
least in the maritime districts. Other considerations lead us to 
imagine high ranges of mountains in the interior, covei’ed with snow, 
and with numerous glaciers descending towards the lower ground. 
The southern Island of New Zealand may be adduced in illustra- 
tion of the supposed conditions of Eastern Australia at this 
period. A similar climate seems to have prevailed in the region 
iiow known as South Africa. I know nothing of the state of the 
southern extremity of South America at this time, but in Brazil 
this Holarctic Lepidodendron flora was abundant. 
The whole globe indeed seems to have enjoyed, for ages upon 
ages, a climate uniformly temperate, moi.st and equable, as is 
testified by the unanimous evidence of the fossil fauna and 
flora. But there came a time when these conditions, while 
remaining unaltered in the Northern Hemisphere, met with a 
partial reversal in the Southern. 
In the Northern regions the Lepidodendron flora continued in 
uudiminished luxuriance for vast periods of time, gradually 
yielding in the Permian to the presence of climates too 
severe or extreme, and to the competitions of hardier natures. 
But long before that period it had entii’ely disappeared from 
the South. A great change in the climates of South Africa 
and East Australia took place, affecting the Marine forms 
of life to an infinitesimal extent, if at all, but sweeping 
away the whole of the Terrestrial flora. This difierence in 
the results of the change, together with other considerations, 
leads us to suppose that it was probably consequent on a land connec- 
tion having been established between Australia and an Antarctic 
continent, with a coincident disruption of the previously existing 
communication between Australia and the great northern con- 
tinent. An extreme or continental climate, with an excessive 
range of temperature, accompanied by violent floods and corres- 
ponding droughts, now superseded the moist and temperate 
