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Problems of Bipolar Plant Distribttion 247contirrent and spared nothing: the entire Antarctic flora, save for the elements which hadextended their area into subantarctic regions and, perhaps, some single moss or lichen upona nunatak or ice-free cliff, fell a victim to the cold. In the later history of the vegetation ofthe globe there is not a seeond instance of such a magnificent destruction. It goes withoutsaying that the Ice Age of the N orth could not have the same effect, owing to the verydifferent geographical situation. Remarkably enough, this has seldom been thought of. Ican find no theory thai gives a better understanding of plant distribution in the far south -the remarkable disjunctions of area, the many strange, isolated gene:ra, the circumpolardistribution of special sections of world-wide genera, the small isolated families - thanthe bare fact that, during the Glacial Epoch, the entire flora of a big contirrent was wellnighextirpated.>> (SKOTTSBERG 1925 a, pp. 31-32.)>>The large Antarctic contirrent was long looked upon as a quantite negligeable in thediscussions on the evolution and migrations of animals and plants; in certain quarters thisaspect is still prevalent. This may not be very surprising, for the southern hemispherecertainly had appearances against it. With the exception of Australia the bulk of the landConsisted of scattered groups of islands harbonring a fragmentary flora, poor in species,which made a quite different and far less imposing picture than the compact boreal .world. The sea dominated entirely, the Antarctic lay ice-bound and lifeJess, nothing wasknown of its history, elirnatic changes etc. and no fossils had been found there. The discaveryof the extinct antarctic flora has completely changed the situation and has once againbrought Iife to the land of the ice age. There the Gondwana flora had its home; it was followedby a Mesozoic flora, and the Arcto-Tertiary flora of the northern hemisphere had itscounterpart in an Antarcto-Tertiary flora. This flora still exists though to a great extentsplit up owing to the present division of land and sea. Therefore, we may, with greater assuranceand greater consistency assign to this land sleeping under its ice covering a leadingrole in the history of Life, not the role of a colony populated from the northern hemisphere,but that of an austral dominion.>> (Translated from SKOTTSBERG 1940 a, p. 55.)Obviously these statements are incompatible with the >>monoboreal relic hypothesis>>.If any further proof against this hypothesjs be needed, it may be found inthe following fundamental statements in FLOlUN 's most recent work, based upona general reyjsion of >>the fossil conifers of southern lands>> (1940, pp. 91-92):>>20. A negative feature of great importance to the composition of the southern fossilconifer floras is the total absence in them of all now living typically northern genera of Cupressaceae,of all Taxodiaceae except Athrotaxis, of Pinaceae and Cephalotaxaceae, Taxaceae withthe exception of one Torreya-like form in peninsular India (and presurnably also of Austrotaxus),and of a considerable number of extinct genera discovered in northern lands. Fromthe Permian, and especially from the Jurassic, up to the present the conifer floras of southernlands are distinguished by very pronounced features from contemporaneous northernfloras. The differences we re as great in the Jurassic as in an y later period. As far as theconifers are concerned, the Jurassic floras were neither as uniform nor as widely distributedas has often been assumed. Under the influence of great changes in the geogenetic andelirnatic conditions, some interchanges between the conifer floras of the two hemispheresand migrations of genera, presurnably along the Malayan-Papuan and to a lesser extentthe Arrdean and Bast-African transtropical bridges, have certainly taken place. But veryfew northern genera appear to have erossed the equator to any considerable extent in pasttimes, which may on the contrary have occurred somewhat more markedly in southerngenera, just as has obviously been the case in a geologically fairly late period.The res11lts obtained contradiet the opinions of STUDT and others that all conifers originatedin the north temperate zone, or in the Arctic regions, and spread from thence to southernlands, including Antarctica. They point instead to the conclusion that the world's