Falkland*, etc.] FLORA ANTARCTICA. 211 



this subject. In 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 east, between the parallels 45° and 04° of south latitude. Throughout this portion 

 of the world the land exhibits a manifest tendency eastward, from the extreme south of the 

 American continent ; for there are 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 Auck- 

 land'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, cha- 

 racterizing isolated groups of islands extending for 5000 miles to the eastward of its own posi- 

 tion ; some of these detached spots are much closer to the African and Australian continents, 

 whose 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 direction as that of the violent and pre- 

 vailing westerly winds*. 



Tierra del Fuego itself is a crowded 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 (i7°, affords a most remarkable instance of this phenomenon, first mentioned by Gmelin and afterwards by 

 Humboldt. Some of the 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 Uaron Humboldt much 

 highly interesting verbal information upon the 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 very 

 striking facts. I must content myself with referring to the preface to Gnieliu's ' Flora Sibirica,' for copious exam- 

 ples of these seeming anomalies in the distribution of vegetables. 



Many striking examples on the other hand may be instanced, of countries closely approximated in geographical 

 position, but unlike in geological and other features, presenting widely different botanical aspects ; such sudden changes 

 in the vegetation we may observe on the east and west flanks of the Andes and on the Himalayan ; in the Floras of St. 

 Helena and Ascension, and the coast of Africa ; or of Tristan d'Acunha and the Cape ; of New Zealand and Aus- 

 tralia ; 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 their influence. An element that will carry particles of dust for 

 hundreds of miles through the upper regions of the air, must be a powerful agent in disseminating the sporules of 

 the lower orders of plants ; so much so indeed that I should unhesitatingly deny the necessity of a double creation, 

 to account for the same species of Moss or Lichen inhabiting any two spots on the globe, however widely apart. 

 That cru-rents of air are not equally efficacious in waiting the .seeds of the higher orders is proved by the ab- 

 sence in the British Isles of many common European plants ; though when once introduced by other means 

 they increase rapidly. We further see that the tide of vegetation (like the population) has, in the intertropical Pa- 

 cific Islands, set in a direction contrary to the prevailing winds, namely, from the Asiatic and not from the American 



