102}. ScHARFF. — S7m)' Reflections on the Irish Alpine Flora. 119 



Ireland that, owing to the mild winters, the}' do not need 

 any protection. Alpine plants in fact do not tolerate 

 extremes of temperature, and it always seems to me strange 

 that so many botanists connect the presence of fossil 

 remains of alpine plants with a former prevalence of an 

 arctic climate. When we wish to grow the rarer species 

 of alpines successfully in the plain, we do not expose them 

 to the cold blasts of winter. We grow them under glass 

 in a frame where they are surrounded by a rather mild 

 temperature and effectively protected from climatic 

 extremes. Most of the alpine plants of Switzerland cannot 

 spread into the lower regions of the country because they 

 would be exposed there to drought, and to extreme cold in 

 the winter. And for this reason horticulturists find it 

 impossible to grow many of the alpines in the open air 

 in the lowlands of central Europe. The wide range and 

 discontinuous distribution of many of the alpine plants 

 indicate that the}'^ could not have spread from east to west 

 or from north to south as long as the climate of Europe 

 resembled the one we have now. It has been suggested 

 that it was during the Glacial Epoch that these plants 

 spread or wandered as we may say across vast stretches 

 of country and thus reached their present habitats. This 

 suggestion is founded on the fact that the remains of a few 

 plants such as Salix polaris, Dryas ociopetala and Betiila 

 nana have been discovered in the lowlands of central and 

 western Europe. But of these only Dryas octopetala can 

 be considered a truly alpine plant, and to judge from its 

 extensive range it must be of great antiquity. Dryas 

 octopetala, as well as all other alpine and northern plants 

 found in Ireland, grows there naturally and apparently in 

 a perfectly healthy condition, in a temperate oceanic 

 climate almost at sea-level. Considering that most of the 

 true alpines can be grown in the lowlands of Ireland, does 

 it not seem as if we might formerly have had similar 

 climatic conditions spread all over the European continent ? 

 Would not such conditions favour the geographical 

 distribution of alpine plants ? Prof. Brockmann-Jerosch 

 indeed supports the view that the cHmate of Europe during 

 the Ice Age must have been oceanic and that the Ice Age 



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