222 R I K A R D S T E R N E R 



In Engler's survey of the flora districts of the world (Engler und Gilg IQI2) 

 South Sweden, in the north bounded by the northern limit of the oak or the 

 sudden transition between the Central Swedish lowlands and the coniferous forest- 

 region of Norrland, is for the most part classed with the Subarctic zone. Only 

 its southernmost part is supposed to belong to the Middle European flora district. 

 This part of South Sweden is divided between two different Middle European 

 flora provinces. The south-western part (Skane) is classed with a Svbatlantic 

 province of a maritime character, while the south-eastern part (Oland and Gotland) 

 is classed with a Sarmatian province, attached to the Pontic province, which com- 

 prises the steppe districts of the South-East of Europe. This division indicates a 

 continental-maritime dualism in the South Swedish flora. As a matter of fact, 

 such a dualism in the flora must be looked upon as highly characteristic of almost 

 the whole of South Sweden. The cleavage between a continental character and 

 a maritime character, in fact, forms a highly conspicuous feature of the South 

 Swedish flora. 



The continental element in the South Swedish flora asserts itself distinctly. A 

 comparatively great number of South Swedish species occur chiefly in the con- 

 tinental parts of Europe; and many of these species reach their definite western 

 limits in South Sweden. 



This feature of the South Swedish flora is in full agreement with the general 

 geographical character of South Sweden as being a transition region between con- 

 tinental East Europe and maritime West Europe. This appears clearly in the 

 climate. 



The South Swedish climate, however, sliows great irregularities in its continental- 

 maritime development. Topography — in the first place the contrasts between 

 the South Swedish highland^ and the surrounding lowlands — has a disturbing 

 influence on the even transition from more continental to more maritime climate 

 conditions in passing from the east to the west. Special stress should be laid on 

 the comparatively strong development of the continental and maritime character 

 which exists on the eastern and the western side of the highland respectively. 



A close examination of the distribution of continental species in South Sweden 

 will show how far they reflect the changes in the continental-maritime develop- 

 ment of the countryside. Hence we get an opportunity of examining the impor- 

 tance of certain geographical factors for the distribution of species. Regarding 

 the history of the flora and geographical conditions of former days we may at 

 the same time get comparatively safe starting points. South Sweden would seem 

 a very suitable area for a study of the distribution limits of continental species 

 in Western Europe. 



* In order to avoid a confusion with the Swedish province Uppland this may perhaps be regarded 

 the most suitable translation of »Sydsvenska hoglandetit . 



