THE CONTINENTAL FLORA OF SOUTH SWEDEN 337 



distributed only in the east of South Sweden have a westerly limit of distribution 

 in the west of North Germany, while some species that have in Denmark and 

 western Scandinavia a westerly limit of distribution have a comparatively easterly 

 limit in North Germany. At the same time it must be pointed out that several 

 species distributed far to the west in North Germany are altogether lacking in 

 the east of South Sweden, while some of these species have occurrences in 

 Denmark and the west of Scandinavia. 



Cpiapter X. 

 Species belonging to the thin foliferous forests of Eastern Europe. 



Their IVlode of Occurrence. 



The thin foliferous forests that are here in question correspond to two types 

 of vegetation in the scheme on p. 233, namely the xerophilous thin foliferous 

 forest (»steppe forests*, dry wooded slopes, brushwood slopes etc.), and secondly 

 the mesophilous thin forests formed of trees which do not throw so much shade. 

 I have combined the types here in order to economize space, and also because 

 several species belonging to different types exhibit similar conditions of distribu- 

 tion in South Sweden. 



We have now passed over to types of vegetation which have their proper 

 domicile in the Middle European flora district, and which contribute to characte- 

 rize that district. In accordance with this fact we shall tind that the flora that 

 distinguishes the types of vegetation has a tolerably uniform composition throughout 

 the whole of Middle Europe. But the fact that there are better conditions for 

 the species falling under this head in continental regions than in maritime ones 

 is shown by the greater number of species in the flora of the lirst-named regions. 



We find both the types of forest that are now in question abundantly repre- 

 sented in the vegetation of Central Russia. 



The xerophilous thin foliferous forest is closely connected with the meadow 

 steppe in the matter of the composition of the flora. There is a connecting link 

 in the >•> steppe forests ». 



These consist of low-growing, thin coppices which appear here and there on 

 the steppes where the conditions of the ground are suitable, as near watercourses 

 or on mounds where the salt in the soil has been leached to a considerable depth 

 (cf. Tanfiljev 1894 and igo6 etc.). As regards the composition of the flora, I 

 can here give only a few slight indications and refer to other publications: e. g. 

 Chirjaev 1907, e. g. pp. 350, 351, 362, and 367 ; and 1910, e. g. pp. 350 and 362 

 [government of Kharkov!; Keller 1903, e. g. pp. 11, 23 [government of Saratov] ; 



