í \
those of Fuegia, separated by 140 degrees of longitude, rather than with those of Lord
Auckland’s group, which is nearer by about 50 degrees. But the featiu’es of the Flora of
Kerguelen’s Land are similar to, and many of the species identical with, those of the American
continent, constraining me to follow the law of botanical affinity in preference to that
of geographical position. Two alternatives presented themselves, each possessing some advantages
over the com-se which is now adopted, of dividing the Antarctic Botany into two large
sections : one, to consider each little island or group as a separate flora; but this would lead
to much repetition, and is not warranted by the amount of novelty exhibited in any of the
groups : the other, to unite all under one head; a plan certainly accompanied with many
advantages, but counterbalanced by the consequent delay of the work, for it would have obliged
tbe author to study the plants of two very different botanical regions at the same time. The
reinai'kable beauty and novelty of the vegetation iu Lord Aucldand’s and the iieighbonring
Islands also merited particular consideration. As it is, some plants described iu Part I. will
re-appear in the present; very few, however ; so few as to excite smprise, when it is remembered
that lands, far more remote from Tierra del Puego than those to the south of New
Zealand, possess the characteristics of the Fuegian Flora.
A certain affinity in botanical productions has often been traced iu widely severed countries,
and Professor E. Forbes* has lately brought geological causes to bear immediately upon
* Professor E. Eorbcs lias connected tlie similarity, long kiiowii to exist between tlie Floras of tlie west of Ireland
and Portugal, with certain geological characteristics belonging to both these now remote, but perhaps once nnited
countries. Thus he also connects the Afiiine Flora of Scotland ivith that of the Scandinavian Alps, and the botany of
the Channel coasts and islands with that of France (idd. ‘ Report of the Meetings of the British Association in Cambridge,
July 1845 ’). Uniformity of surface is generally accompanied by a similarity of vegetation throughout an
extended region. When such a surface becomes divided we are apt to conclude that the isolation of the lesser portion
preceded the migration of plants from the larger; in short, that the identity of the Norfolk and Suffolk Flora
with that ot Holland must be due to the fonner havung been peopled with plants hy the latter, subsequently to the
German Ocean having assumed its present position; and not that the two together formed an equally well clothed
and extended plain, reaching, as Hiunboldt believes, from North Brabant to the Steppes of Asia; its western portion
having been afterwards insulated by tbe influx of tbe North Sea. The uniformity of surface in the vast continent
of Africa is becoming daily more evident, as the mountains of the moon recede before the intrepid explorers of the
sources of the true Nile. It were natm-al to suppose that a barrier, such as they were conjectured to be, would ex-
liibit changes in the vegetation, equally marked with those produced by the Cordfllera, Himalayah, and other mountain
chains wherever they may occur. A further proof of the suspicious nature of the reports that any veiy extensive
and elevated land exists in Africa appears to me evident in the character of Abyssinian vegetation. Mi-. Brow-n
first showed that it possessed types of the Cape Flora, and lately I received the most ample confii-mation of these
views from M. Eichard, who exhibited to me a beautiful series of drawings of Abyssinian plants, made by the late
unfortunate French travellers, amongst which were numerous FroteacetE, Asclepmdm, Orchidea, Iriders, and Amarylli-
dea, of forms which the Cape alone was supposed to possess. Central Eastern Africa is perhaps the most interesting
spot in the world for a botanist; it contains not merely Cape orders, but others typical ot Madagascar, tlic
East Indies, Arabia, both the northern and western coasts of Africa itself, and on its high mountains those even ot
Em-ope. The uniformity of the surface and Flora of Australia is equally evident.
There ai-e, however, instances ot a sudden change in the vegetation occurring, nnaccompanied with any diversity
ill 1:
this suhject. Ill reference to this curious topic I would adduce, as corroborative perhaps of his
speculations, the general geographical arrangement of those islands, whose botany I am about to
describe as that of one country. They stretch from Fuegia on the west, to Kerguelen’s Land
on the oast, between the parallels 45° and 04° of south latitude. Throughout this portion
of the world the land cxliibits a manifest tendency eastward, from the extreme south of the
American continent; for there arc no fewer than five detached groups of islands between Fuegia
and Kerguelen’s Land, but none between the latter island and the longitude of Lord Auckland’s
group, nor between this last again and the western shores of Fuegia and Patagonia.
Tierra del Fuego and the neighbouring southern extremity of the American continent
appear to be the region of whose botanical peculiarities all the other Antarctic Islands, except
those in the vicinity of New Zealand, more or less evidently partake. It presents a Flora, characterizing
isolated groups of islands extending for 5000 miles to the eastward of its own position
; some of these detached spots are much closer to the African and Australian continents,
whoie vegetation they do not assume, than to the American; and they are all situated in
latitudes and under circumstances eminently unfavourable to the migration of species, save
that their position relatively to Fuegia is in the same dii-ection as that of the violent and prevailing
westerly winds*.
Tierra del Fuego itself is a crow-ded archipelago, forming the southern extremity of
of geological or other feature. The river Obi, in Siberia, whose direction is towards the north-west, from the latitude
of 50° to 67°, affords a most remarkable instance of this phenomenon, fii-st mentioned by Gmelin and aftei-wards by
Humboldt. Some of tbe most conspicuous trees attain either of its banks, but do not cross them, those of the regions
to the west of this stream re-appearing only on the confines of China. I have received from Baron Humboldt much
highly interesting verbal infoi-mation upon tbe distribution of organized beings in Siberia; the disappearance of some
animals and plants over a vast area, and their re-appearance in another, in obedience to no known law, are ven-
striking facts. I must content myself with referring to the preface to Gmelin’s ‘ Flora SAirica,’ for copious examples
of these seeming anomalies in the distribution of vegetables.
Many striking examples on the other band may be instanced, of countries closely approximated in geographical
position, but unlike in geological and other featm-es, presenting widely different botanical aspects ; such sudden changes
in the vegetation we may observe on tbe east and west flanks of the Andes and on the Himalayah; in the Floras of St.
Helena and Ascension, and the coast of Africa; or of Tristan d’Acunha and the Cape; of New Zealand aud Australia
; of Juan Fernandez and the Galapagos and the coast of America; of Madagascar and South Africa; but more
especially in the disparity that prevails between the Floras of the separate islands of the Galapagos and of the
Sandwich group.
* The prevalence of certain winds in favouring the migration of plants must not be overlooked, though too
much stress has been laid by some writers upon then- influence. An element that will can-y particles of dust for
lumdreds of miles through the upper regions of the afr, must be a powerful agent iu disseminating the sporules of
the lower orders ot plants; so much so indeed that I should imhesitatingly deny the necessity ot a double creation,
to account for the same species of Moss or Lichen inhabiting any two spots on tbe globe, however widely apart.
That cim-eiits of air are uot equally efficacious in wafting the seeds of the higher orders is proved by the absence
in the British Isles ot many common Em-opean plants ; though when once introduced by other means
they increase rapidly. IVe further see that the tide of vegetation (like the popidation) has, in the intertropical Pacific
Islands, set in a dii-ection contrary to the prevailbig winds, namely, from the Asiatic and uot from the American