ic
floras.

If the Fuegian flora was treated in the analogous way (and this would
incidentally show how far the Cordillera are a high-road of genera), I
should then be prepared far more easily and satisfactorily to understand
the relations of Fuegia with the Auckland Islands, and consequently with
the mountains of Van Diemen's Land. Moreover, the marvellous facts
of their intimate botanical relation (between Fuegia and the Auckland
Islands, etc.) would stand out more prominently, after the Auckland
Islands had been first treated of under the purely geographical relation
of position. A triple division such as yours would lead me to suppose
that the three places were somewhat equally distant, and not so
greatly different in size: the relation of Van Diemen's Land seems so
comparatively small, and that relation being in its alpine plants, makes
me feel that it ought only to be treated of as a subdivision of the
large group, including Auckland, Campbell, New Zealand...

I think a list of the genera, common to Fuegia on the one hand and on
the other to Campbell, etc., and to the mountains of Van Diemen's Land
or New Zealand (but not found in the lowland temperate, and southern
tropical parts of South America and Australia, or New Zealand), would
prominently bring out, at the same time, the relation between these
Antarctic points one with another, and with the northern or Arctic
regions.

In Article III. is it meant to be expressed, or might it not be
understood by this article, that the similarity of the distant points
in the Antarctic regions was as close as between distant points in
the Arctic regions? I gather this is not so. You speak of the southern
points of America and Australia, etc., being "materially approximated,"
and this closer proximity being correlative with a greater similarity of
their plants: I find on the globe, that Van Diemen's Land and Fuegia are
only about one-fifth nearer than the whole distance between Port Jackson
and Concepcion in Chile; and again, that Campbell Island and Fuegia
are only one-fifth nearer than the east point of North New Zealand and
Concepcion. Now do you think in such immense distances, both over open
oceans, that one-fifth less distance, say 4,000 miles instead of 5,000,
can explain or throw much light on a material difference in the degree
of similarity in the floras of the two regions?

I trust you will work out the New Zealand flora, as you have commenced
at end of letter