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Falklands, etc.] evident, though to enumerate them would be out of place here; those between the latter island and Tristan d'Acunha are indicated by the genera Phylica and Geranium, and also by some of the Ferns and Lycopodia: as, however, it is also through those genera that the botany of Tristan d'Acunha resembles that of the Cape, it may fairly be doubted whether the apparent affinity with St. Helena is not imaginary. It is a very remarkable circumstance that while these three islands all possess some of the features of the African Flora, the predominant ones are absent ; thus, whilst the St. Helena Flora is allied, and exclusively so, to that of the Cape in Geranium, Melhania, and Phylica, it has no representatives of entire Orders, namely Proteacece, Putacece, Owalidece, Crassulacece, Ericece, Bestiacece, and many others, far more characteristic of the African vegetation than are any of the plants inhabiting St. Helena,

The other islands whose plants will find a place in this division of the 'Antarctic Flora' are situated south of the Indian continent, widely apart from the American, and so far as geographical position is concerned, belong to Africa or India; these are, Prince Edward's and Marion Islands, the Crozets, Kerguelen's Land, and the Islands of Amsterdam and St. Paul.

Of the two first-mentioned groups the vegetation is wholly unknown; the former, Prince Edward's and Marion, are small contiguous islets in the 47th degree of latitude and 38th of east longitude; they are of rather an undulating outline and evidently volcanic formation, from a little distance they appeared covered with grass. The Crozets are a group of much larger islands, situated in the 48th degree of latitude and between the 47th and 49th meridian, east of London: they are bold rocky masses, rising to a height of 6000 feet; some, though of considerable size, are quite inaccessible, and others enveloped by eternal fogs, whence almost the whole of its native flowering plants and several of its genera being peculiar. Various causes have, within the memory of man, reduced this flora to a mere shadow of what it once was, for when the island was discovered, it is described as entirely clothed with forest. The greater part of this was said to be destroyed by the introduction of goats and pigs, and by the bark of the trees being stripped for tanning, so that the flora is consequently now very limited both in number of species and of individuals. During the interval that elapsed between two visits which I paid to St. Helena, one very peculiar native plant, the Acalypha rubra, had disappeared, and two other handsome shrubby species of Melhania, with particularly showy flowers, had very recently become extinct; whilst the existence of some Wahlenbergia, of a Physalis, and a few of the peculiar arborescent Composite&aelig;, though thus far prolonged, is held upon a very precarious tenure. These plants are all well marked species, which on the destruction of the forests seem unable to accommodate themselves to their altered circumstances, perish, and are replaced by introduced species, exactly as is the case with various savage races of mankind, which do not suit themselves to the condition of the soil when altered by the European settler, but diminish in number and dwindle away even when violent measures have not been used for their extirpation. I may remark, that species in isolated islands are generally well defined; this is in part the natural consequence of another law which I have observed, that genera in islands bear a large proportion to the species, or in other words, that genera are small, seldom containing more than two or three species, and very frequently solitary representatives. It must be borne in mind that this well-marked character of the species in insular localities applies equally to mountainous as to planer islands. It might seem natural to suppose that a varied surface would have the effect of obliterating specific distinction, especially in small areas, as the Pacific Islands, the Galapagos, St. Helena, and the like, whose present contour is not the result of recent geological changes, and where time, the required element for developing such species as are the offspring of variation, has been granted.