340 Notice of Dr. Hooker's Flora of New Zealand. 
over run great risk of distortion in the hands of those who do not know 
the value of the evidence they afford. I have endeavored to enumer- 
ate the principal facts that appear to militate against the probability of 
the same species having ligt in more places (or centres) wit 
one ; but in so doing e only partially met the strongest argum 
how does it happen that Edwardsia grandiflora inhabits both New 
Zealand and South America? or Oxalis Magellanica both these local- 
ities and Tasmania? ‘The idea of span igir a by aerial or oceanic 
currents cannot be entertained, as the seeds of neither could stand ex- 
posure to the salt water, and they are er heavy to be borne in the air. 
Were these the only plants common to these uae sundered localities, 
the possibility of some exceptional mode of transport might be admit- 
ted by those disinclined to receive the doctrine of double centres; but 
the elucidation of the New Zealand Flora has brought up many sini r 
instances equally difficult to account for, and has developed innumera- 
ble collateral phenomena of equal importance, though not of so evident 
appreciation. Th re which all bear upon the same point, may be ar- 
i al as follows 
. Seventy-seven a iene are common to the three great pout oe 
ate masses of land, Tasmania, New Zealand, and South 
Comparatively few of these are universally disibted peta be 
the greater part being peculiar to the south temperate zo 
3. There are upwards of 100 genera, subgenera, or aye well- 
marked groups of plants entirely or nearly confined to New Zealand, 
Australia, e: extra- -tropical So ze America. These are represented 
y one or more species in tw more of these countries, and they 
thus effect a botanical ralaniaalip: or affinity between them all, which 
every botanist ie ene! es. 
4. 
ese three peculiarities are shared by all the islands in the south 
temperate zone aia luding even ‘Tristan d’Acunha, though placed so 
close to Africa), between which islands the transportation of seeds is 
even more unlikely than between Ai larger masses 0 
he plants of the Antarctic islands which are equally natives of 
New Zealand, Tasmania, and Australia, are almost invariably found 
only on the lofty mountains of these countries. 
Now as not only individual species, but groups i these, whether or 
ders, genera, or their subdivisions, are to a great degree distr yisled 
se la 
any other attribute of insularity, which indicates the nature of the vf 
culiarity of endemic species, The islands of each ocean ‘oe i 
i u 
others to the North Pacific ilsiate, others to those of the § en 
and others again to the Malayan Archipelago; just as there are 
