126 Knud Jessen: Rosaceæ. 



temperate forms, viz. Rubus saxatilis, R. arcticus and Alchi- 

 milla vulgaris; they have extended more or less further to- 

 wards the north, and have in several places passed beyond 

 the Polar Circle. To these Sorbus americana may also be 

 referred. This and the two Rubus-species have endozoic 

 or at least synzoic fruit-dispersal, and the Rubiis-species 

 (especially R. arcticus) have attained a very wide distri- 

 bution. 



Alchimilla alpina is presumably an Alpine form, which 

 has probably during the Glacial period migrated north- 

 wards and has in Scandinavia passed over the Polar 

 boundary (Buser in Schröter; 1. c). 



12.— 3.— 1914. 



