IS 77.] 
Southern Hemisphere. 
343 
the same time as that of the northern, as it occurred when 
the land stood relatively to the sea higher than it now does. 
There is the same objection to its being movements of the 
land that effected this, as there is to the theory of similar 
land movements in Great Britain, for the New Zealand 
geologists would send their country 3000 feet up into 
the air to allow the glaciers to descend to the present sea- 
level, and lower it 2000 feet to permit the gravels of the 
plains to be spread out, making a total movement of more 
than 5000 feet; yet after these enormous imaginary oscilla- 
tions, we find everywhere, as we do in England, the pre- 
glacial shell beds with their littoral species only within a 
a few feet of the present shore line. 
Let us now turn to the consideration of the question of 
the origin of the great plains of drift and silt that border the 
eastern and southern coasts. Dr. Haast, in his able essay 
on the structure and origin of the Canterbury Plains, con- 
sidered that the gravels were the exuviae from the great 
glaciers of the interior that had been spread out by the 
floods produced whilst it was melting. Some serious objec- 
tions have been urged against this view. The sheets of 
gravel wrap around the hills, and are spread right across 
the water-sheds between different river systems. They are 
nearly level for scores, or even hundreds of miles. Ranges 
of hills are isolated so that they rise up from the plains like 
islands out of the sea. The waters, necessary to overflow 
such an extent of country, would be raging torrents, which, 
instead of depositing sediments, would sweep everything 
before them into the ocean ; and would be rather agents of 
destruction and denudation than of deposition above the sea- 
level. There are beds of silt up to 800 feet above the sea- 
level at Banks’s Peninsula, and for the deposition of these 
beds we require the presence of tranquil waters, and not 
torrential floods. It may also be remarked that it is not 
probable that, even on the hottest day, sufficient ice could 
be melted to produce the quantity of water required to sub- 
merge the country next the sea shore beneath a flood several 
hundred feet deep. The very statement of the enormous 
quantity of water required seems to condemn the theory 
when we remember that every day the water produced 
would be carried off, if near the sea there was nothing to 
stop its outflow and dam it back. 
These considerations have led the generality of New 
Zealand geologists to adopt the theory that the great sea- 
ward plains are of marine formation, and that the gravels, 
sands, and loams were spread out when the land stood much 
