364 RIKARD STERNER 



Some few species are to be regarded as natural elements in the flora of South 

 Sweden: Cnidium venosum, Dianthus superbus, Inula britannica, Scutellaria hasti- 

 folia, and Veronica longifolia. These are found in natural wet meadows on river 

 banks; Cnidium, Scutellaria and Veronica also on the seashore. To these must 

 be added Petasites spurius, which in the south of Scandinavia, as in Russia, be- 

 longs to the colony-like vegetation of sandy banks and shores. 



The distribution of the species exhibits one or two remarkable features which 

 must here be briefly pointed out. 



Some species push out somewhat from a distribution region in the east of 

 Europe westwards over the Baltic flora region, while they are as good as entirely 

 absent from Central Europe. Such species are Cnidium venosum (Plate 20), 

 Ononis arvensis and Petasites spurius. Species with a mode of occurrence like 

 those named have evidently great possibilites of spreading from the east over 

 the Baltic lowlands (cf. pp. 242 and 371). 



Dianthus superbus has a distribution which possesses a certain amount of 

 interest. A great distribution area which comprises the whole of Eastern and 

 Central Europe extends into the Scandinavian Peninsula only, in the south, across 

 Denmark into Skane and into southern Halland, and, in the north, across to the 

 north of Finland into the extreme north of Norway. In Finland the species is 

 found only in the east and in the north. As it is widely distributed in the east 

 of the Baltic and the north-east of Germany, however, it is remarkable that it is 

 altogether lacking in the south-east of Sweden. 



Veronica longifolia, which is similarly distributed throughout Eastern and Central 

 Europe (and is also found all over Finland) has quite a different distribution in 

 Scandinavia. From Denmark it extends up along the west coast of Sweden from 

 the north-west of Skane in the south. In the Vanern districts it is found not 

 only on the shores of Lake Vanern, but also has occurrences on the uplands of 

 central Varmland and the interior of Dalsland. This distribution-area in the west 

 of Sweden is connected with a distribution-area in the south-east of Norway. In 

 the east of Sweden the species is found on the coast from the skerries of Ble- 

 kinge in the south as far as the river Tornealv, where there distribution is connected 

 with that in Finland. On the Swedish coast, however, there are certain gaps: it 

 should especially be noticed that the species is lacking in Smaland and on Oland 

 and Gotland. In the extreme north of Norway, moreover, the species extends 

 from north Finland to Alten and Inner Finmarken in the west. 



Thus this species, thanks to its distribution in Finland, has been able ro reach 

 the east coast of Central and Northern Sweden. It has also reached the coast of 

 Blekinge, probably across the south of the Baltic. But this species also is lacking 

 in a great part of the south-east of Sweden, in spite of its abundant distribution 

 in the east of Balticum and the north-east of Germany. 



