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 features 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 course 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 the author to study the plants of two very different botanical regions at the same time. The remarkable beauty and novelty of the vegetation in Lord Auckland's and the neighbouring Islands also merited particular consideration. As it is, some plants described in Part I. will re-appear in the present; very few, however; so few as to excite surprise, when it is remembered that lands, far more remote from Tierra del Fuego 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 in widely severed countries, and Professor E. Forbes[1] has lately brought geological causes to bear immediately upon
- ↑ Professor E. Forbes has connected the similarity, long known to exist between the Floras of the west of Ireland and Portugal, with certain geological characteristics belonging to both these now remote, but perhaps once united countries. Thus he also connects the Alpine Flora of Scotland with that of the Scandinavian Alps, and the botany of the Channel coasts and islands with that of France (vid. '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 of Holland must be due to the former having been peopled with plants by 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 Humboldt believes, from North Brabant to the Steppes of Asia; its western portion having been afterwards insulated by the influx of the 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 natural to suppose that a barrier, such as they were conjectured to be, would exhibit changes in the vegetation, equally marked with those produced by the Cordillera, Himalayan, and other mountain chains wherever they may occur. A further proof of the suspicious nature of the reports that any very extensive and elevated land exists in Africa appears to me evident in the character of Abyssinian vegetation. Mr. Brown first showed that it possessed types of the Cape Flora, and lately I received the most ample confirmation of these views from M. Richard, who exhibited to me a beautiful series of drawings of Abyssinian plants, made by the late unfortunate French travellers, amongst which were numerous Proteaceæ, Asclepiadeæ, Orchideæ, Irideæ, and Amaryllideæ, 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 of Madagascar, the East Indies, Arabia, both the northern and western coasts of Africa itself, and on its high mountains those even of Europe. The uniformity of the surface and Flora of Australia is equally evident.
There are, however, instances of a sudden change in the vegetation occurring, unaccompanied with any diversity
