336 RIKARD STERNER 



bution in North Germany are totally missing in Scandinavia, such as Dianthus 

 carthusianorum, Carex praecox, and Astragalus cicer. 



Summary. 



1 . The occurrences of the steppe species in South Sweden are situated in the 

 eastern part of that area, or are strongly concentrated there. They are found 

 mainly in the calcareous districts, on the great arable areas, on sandy fields, 

 and on the slopes of the os-ridges. 



2. The region in South Sweden within which the distribution of the steppe 

 species more or less completely falls can be defined thus: in the north the 

 boundary runs from the lower part of the Dalalven in an approximately south- 

 western direction across the plains of Vastmanland and Narke to the central 

 part of Vastergotland, where it turns off" in a south-easterly direction and passes 

 through Smaland down towards the Kalmar district. From here the boundary 

 runs westward, enclosing parts of Blekinge and Skane, though it should be ob- 

 served that several species distributed in the eastern part of Central Sweden are 

 altogether absent or rare in Skane and Blekinge. 



3. The present distribution of the steppe species in South Sweden seems, 

 as a rule — so far as we can form an opinion at present on such questions — 

 to be determined by the present geographical conditions of the region, its climate, 

 the nature of its soil and topography, in connection with the capacity of the 

 species to spread themselves. 



4. In some cases we are compelled to have recourse to another mode of 

 explanation — the species have occurrences that are relics of a distribution which 

 was wider in former days and which was made possible by more favourable 

 geographical conditions. 



5. The distribution of the species throughout Scandinavia and Denmark may 

 be said to be divided into two branches — an eastern one and a western one, 

 parted by the South Swedish highland. Many species have the western branch 

 marked by only a few isolated occurrences, which are probably mere relics, 

 while other species lack this branch altogether. But there are also some species 

 that have no eastern branch. 



6. The distribution of the species on the other side of the Baltic is usually 

 in accordance with the Scandinavian distribution: species restricted to the east 

 of South Sweden reach their western limit in the east of North Germany, while 

 species that are found in western Scandinavia and Denmark also have a di- 

 stinctly more westerly limit of distribution in North Germany. Nevertheless it 

 is to be noted that there are exceptions to this: one or two species that are 



