76 CARL SKOTTSBERG, A BOTANICAL SURVEY OF THE FALKLAND ISLANDS. 



3) that, before the Ice Age, coniferous forests of Chilean type existed in the 

 islands, but that ± large areas were inhabited by oceanic heath or meadow not very 

 unlike the present one; 



4) that, to judge from the present distribution of the Conifers in question, 

 the climate was warmer, but not necessarily drier then now; 



5) that, with the deterioration of the climate which finally led to the Ice Age, 

 the forests disappeared, the tundra-like formation galning more and more ground; 



6) that the Falklands were never glaciated, but that the Ice Age was repre- 

 sen ted by the Period of Solifluction; 



7) that, during this time, a large number of species may have survived ; 



8) that, in postglacial times, many species immigrated from the West ; 



9) that the »termophilous» element in the flora probably did not survive the 

 solifluction, but immigrated in postglacial time; 



10) that this element rnay have come directly from its present habitat, but 

 also that at least two of the species + one endemic present difficulties; it is more 

 easy to understand their presence in the Falklands, if we assume that the climate 

 of Fuegia lias under gone postglacial changes, which permitted a number of termo- 

 philous species to extend their boundaries to the south. 



The iiiflueiice of man npoii the vegetation. 



It must be considered as certain that the colonisation of the Falklands has 

 exercised a great influence upon the flora and vegetation. In some cases historical 

 documents in the sliape of earlier publications on botany prove this, but we can in- 

 deed suppose, that there is hardly a plant association that has not been affected; it 

 is not necessary to assume that a larger number of species has been exterminated, 

 but I think that the frequency of numerous species has undergone considerable 

 change. Thus we k now that one of the most conspicuous associations, once widely 

 spread, now occupies very restricted areas : the Poa flabellata-association. To judge 

 from what has been said by J, D. Hooker, the cattle started the destruction, w^hich 

 made rapid progress after the introduction of sheep in 1850 — 60. If we compare 

 the statements in »Flora antarctica» with those of to-day, we come to the conclu- 

 sion, that the following species are likely to be destroyed by and by: Alopecurus 

 antarcticus, Carex trifida, HierocJiloé ^nagellanica, Poa antarctica, arundo and jlahellata. 

 Of these, Poa antarctica is still fairly common, but must have been really abundant 

 in earlier times. It is also stated that not few species are less common thenTO years 

 ago, especially Arabis 7nacloviana, Calandrinia Feltonii, Senecio Darwinii, Trisetum 

 subspicatum. It is also very probable that Veronica elliptica was once more com- 

 mon than now, for Mr. Felton told me that sheep use to nibble the bark, which 

 often kills the branches. 



Some species, as Carex acaulis and decidua, Draba falJdandica, Schizcea fistulosa, 

 Uncinia brevicaulis etc. have only been found once and not in the last 70 years. 



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