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AMERICAN JOURNAL OF BOTANY 
[Vol. io, 
species, compared with over 800 in Australia. In short, the differences be¬ 
tween the floras of the two main divisions of Australasia far outweigh the 
resemblances, and we must conclude that each country owes comparatively 
little to the other for contributions to its flora. 
The Fuegian Element 
Of special interest is the occurrence in New Zealand of many species 
either identical with, or closely related to, those of Patagonia and the 
adjacent regions. 
Between the Chatham Islands east of New Zealand, and Juan Fernandez 
off the coast of Chile, lies almost exactly one fourth the circumference of 
the globe, and there is absolutely no intervening land. In spite of this, the 
relationships between the vegetation of the two regions are perfectly ob¬ 
vious, and indicate unquestionably the former existence of land communi¬ 
cation of some sort. No less than 68 genera are common to the two regions, 
and many of these are peculiar to them, although there are widespread 
genera as well. 
Scottsberg, 9 one of the more recent students of this interesting problem, 
recognizes three categories of these common genera: 1, predominant Austral¬ 
asian genera, with American representatives; 2, Andine or Patagonian 
genera, with Australasian representatives; and 3, bicentric genera, con¬ 
sidered to be remnants of an ancient antarctic flora. Examples of the first 
category are Astelia, Lomatia, Orites, Drimys, Drapetes, Pseudopanax. 
The second type may be represented by Enargia, Fuchsia, Pernettya, 
Jovellana, Ourisia. Of the third, Oreobolus, Libertia, Nothofagus, Laure- 
lia, Muehlenbeckia, Gunnera may be mentioned. 
Twenty-five species are recognized as identical between New Zealand 
and Patagonia, and about the same number are doubtfully distinct. 
As we have already indicated in a previous paper, this Fuegian element 
is also strongly developed in Tasmania, and to a lesser degree in Victoria 
and the higher mountains of New South Wales and Queensland. 
Conclusion 
It is generally admitted that the present land surface of New Zealand 
is very much reduced from an earlier period. This is indicated both by the 
extent of shallow sea surrounding the islands, and also.by the distribution 
of the vegetation. Both of these facts point to a union of the islands into 
a single mass of much greater extent, and this at a recent period, geologically. 
The great preponderance of the Malayan element in the vegetation 
indicates land extensions to the north, and this is borne out by soundings. 
There are two submarine ridges extending northward from New Zealand. 
9 Scottsberg, C. Notes on the relation between the floras of subantarctic America and 
New Zealand. Plant World 18: 129-142. 1915. 
