THE ORIGIN OF THE FAUNA AND FLORA OF NEW ZEALAND. 271 
sub-tropical, and 15 per cent. are endemic. As about 44 per 
cent. of the total flora is antarctic, 48 per cent. sub-tropical, and 
18 per cent. endemic, it would appear that the special adaptation 
of antarctic plants to cold regions has not availed them very 
much. For, composing 44 per cent. of the whole vegetation, 
they have only obtained to 48 per cent. of the alpine flora. 
Some of our Alpine species belong to quite sub-tropical genera— 
as Myrsine, Cyathodes, Dacrydium, and Phyllocladus ; but there 
is no large genus in New Zealand that is not represented by 
alpine forms. On the other hand only about 35 per cent. of 
the antarctic species are alpines, the other 65 per cent. living on 
the lowlands; and out of 56 antarctic genera, about one-half 
have no alpine species at all. Again, out of 189 New Zealand 
alpine species, only 13 are found elsewhere—g in Australia or 
Tasmania, and 4 in Fuegia—so that 93 per cent. are endemic. 
Out of 64 alpine genera only 17 are confined to the Alps, and 7 
of these are endemic. These facts show that our alpine flora 
has, on the whole, grown out of the lowland flora, and that the 
arrival of alpines, as alpines has been quite exceptional. The 
ancestral forms have arrived on the lowlands, and their descen- 
dants have gradually worked their way up the mountains. Mr. 
Wallace has remarked that alpine plants are particularly well 
placed for dispersal, on account of the high winds so common in 
mountains. ‘This is quite true, and explains their migration from 
mountain top to mountain top along a chain; but it will not 
apply to the spread of plants to distant islands, because, although 
more seeds of alpine than of lowland plants would be blown 
away, all would arrive on the island at or near sea-level, and 
thus the alpines would not find their accustomed station, while 
the fewer seeds blown or carried by birds from lower levels would 
have a better chance of living in their new home. Alpine plants 
might succeed if they were blown into higher latitudes, but they 
would have less chance than lowland plants in a migration to- 
wards the equator. So that in the case of a migration between 
New Zealand and an antarctic continent, alpine plants of the 
former would more readily pass to the latter than the antarctic 
plants to New Zealand. 
From these considerations it appears evident that antarctic 
plants would have but a slight chance of establishing themselves 
in New Zealand if it were of smaller dimensions than at present, 
and especially if the surrounding seas were warmer, as appears 
to have been the case in the oligocene and miocene periods. 
These plants must therefore have come either during cold periods, 
of which there is no evidence, or else they must have come dur- 
ing those periods of elevation in which New Zealand stretched 
more to the south. This last supposition is certainly the more 
reasonable, and it agrees well with the proportion of endemic 
species found in the antarctic and North Temperate elements. 
There must therefore have been a greater continuity of land be- 
tween Fuezia, Kerguelen’s Land, and New Zealand in both the 
eocene and the pliocene than there is now. Whether this land 
