502 Transactions.— Miscellaneous. 
the tertiary and secondary floras of New Zealand and Australia will help 
much towards elucidating this problem, but the paleo-botany of this 
part of the world is yet in its infancy, and very little is known on the 
subject. 
It may be considered that too much stress is laid in this explanation on 
the elevation and subsidence of great masses of land, but a little considera- 
tien will show that this is not the case. The deeply gouged-out character 
of our western lakes and sounds shows that they were cut out by ice, and 
to account for this we must either assume that the land stood very much 
higher than it does now, or the climate was very much more frigid. But 
even in the latter case we must assume a considerable elevation, as glacier 
action would cease at or very near sea-level, and our sounds are gouged 
down to great depths below present sea-level. Further, most of the low- 
lying eastern portions of this island have been formed at comparatively 
recent times by the denudation of our mountain chains, and most of this 
eastern coast is rapidly—one might almost say visibly—rising out of the 
sea. Again, the occurrence of fringing and barrier reefs in tropical seas is 
an almost certain mark of subsidence, as coral zoophytes cannot live at 
greater depths than about 120 feet, so that when we find these hugh masses 
of rock surrounding islands, and standing out of an ocean in some cases 
1,000 fathoms or more in depth, we are bound down to the conclusion that 
the base on which the zoophytes commenced their labours was only a few 
fathoms from the surface, though now 6,000 feet deep. 
In bringing these remarks to a close, I may just point out that a pro- 
bably most important factor has been throughout left out of our calcula- 
tions, viz., the physical changes which have affected the whole of our globe 
during comparatively recent geological epochs. Many theories have been 
advanced of late years to account for the glaciation of parts of the northern 
hemisphere, and the theorists have in some cases called in as auxiliaries all 
the powers of heaven and earth. But we may be sure that whatever causes 
could lead to results which are so apparent in one large portion of the 
world, must have at the same time caused great alteration in all other 
parts. But until we know with more certainty than we do at present what 
these great causes were, we cannot estimate what their effects on this por- 
tion of the world have been. 
