502 Transactions. — Miscellaneous. 



the tertiary and secondary floras of New Zealand and Australia will help 

 much towards elucidating this problem, but the palaeo-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. 



