1030 Saxifraga rivularis L.

This widespread, somewhat variable, mainly arctic species belongs to the circumpolar plants (Hultén, Circumpol. Il, p. 36 and map 27). A few lower taxa are distinguished, for instance var. flexuosa (Sternb.) Engl. & Irmsch. in E. Asia and northwestern N. America and the Rocky Mts. S. hyperborea R. Br., a form of S. rivularis according to Engler & Irmscher, is mapped separately (no. 1031). The S. rivularis populations in the mountains E of Lake Baikal and the Kolyma Range and in the mountains of Washington may belong to S. hyperborea. S. bracteata D. Don (syn.: S. rivularis var. laurentiana [Ser.] Engl.) in the Pacific region of E. Asia and northwestern N. America is mapped here.