G. M. Tuomson.—On the Origin of the New Zealand Flora. 487 
Zealand and those of South America, Europe, and the antarctic regions 
respectively, and further pointing out some remarkable Pacific Island 
peculiarities in our flora, Hooker concludes by stating that the existing 
botanical relationships ‘‘ cannot be accounted for by any theory of trans- 
port or variation,” but that they are ‘“ agreeable to the hypothesis of all 
being members of a once more extensive flora which has been broken up by 
geological and climatic causes.” 
Leaving out of account minor speculations on this subject, we may next 
consider the second writer named, who deals—although indirectly—with 
the question. 
Prof. Hutton’s theory*, deduced from the distribution of the struthious 
birds in the southern hemisphere, is that there formerly existed a great 
‘‘antarctic continent stretching from Australia through New Zealand to 
South America, and perhaps on to South Africa. This continent must have 
sunk, and Australia, New Zealand, South America, and South Africa, must 
have remained isolated from one another long enough to allow of the great 
differences observable between the birds of each country being brought 
about. Subsequently New Zealand must have formed part of a smaller 
continent, not connected either with Australia or South America, over which 
the moa roamed. This must have been followed by a long insular period, 
ending in another continent still disconnected from Australia and South 
America, which continent again sank, and New Zealand assumed somewhat 
of its present form.” 
It is of course assumed that this former extensive antarctic continent 
existed at a date anterior to the first occurrence of either in Aus- 
tralia or South America, and consequently that all subsequent immigrants 
from Australia, or from the islands lying to the north, must have found 
their way across the intervening expanses of ocean. Professor Hutton recog- 
hizes many of the difficulties in the way of this theory, as, for example, the 
Occurrence of grass-birds (Spheneacus) in both Australia and New Zealand, 
and the existence of the genus Ocydromus (woodhens, ete.) in New Zealand, 
Lord Howe’s Island, and New Caledonia; as the birds of both these genera 
are almost or quite unable to fly. 
The examination of our fresh-water fish leads him to the « 
“either that our connection with Australia was later than with South 
America, or that in the old continent New Zealand and Australia were 
- Inhabited by one, and South America by another species” of the grayling 
family. ae ee prove that — a bead 
Fe ea 
On the Geographical Relations of the BZ. Fauna, by Captain Er Ww. bans tc me 
Ze NZ. a es p. 227. . ae 
