98 



Rydberg: Phytogeographical notes 



American Endemic Alpine Plants 



More than one third of the alpine plants of the Rockies are 

 endemic and if the subalpine element found just over the timber- 

 line, or occasionally higher up, is included, this proportion is 

 increased to about half of all the species. Several of these are 

 apparently derived from circumpolar glacial or arctic plants. 



Southern Rockies 



Deschampsia alpicola 

 Ranunculus Macauleyi 

 Parrya platycarpa 

 Leptasea chrysantha 

 Muscaria delicatula 

 Muscaria micropetala 

 Saxifraga debilis 

 Saxifraga simulata 

 Potentilla modesta 



Northern Rockies 



Salix nivalis 

 Draba lonchocarpa 

 Muscaria monticola 

 Micranthes Rydbergii 

 Micranthes crenatifolia 

 Spathidaria Vreelandii 

 Phyllodoce empetriformis 

 Phyllodoce glandidiflora 

 Cassiope Mertensiana 



Circumpolar glacial or arctic 



D. caespitosa 

 R. nivalis 

 P. macrocarpa 

 L. Hir cuius 

 M. caespitosa 

 M. caespitosa 

 S. rivularis 

 S. cernua 



P. nivea (perhaps through P. 

 quinquefolia) 



Circumpolar glacial or arctic 



5. reticulata 

 D. nivalis 

 M. caespitosa 

 M. hieracifolia 

 M. nivalis 

 S. stellar is 

 P. coerulea 

 P. coeridea 

 C. tetragona 



Southern and Northern 



Rockies Circumpolar glacial or arctic 



Micranthes rhomboidea M. nivalis 



Micranthes arnoglosa M. nivalis 



Taraxacum scopulorum T. arcticum 



Salix saximontana S. reticulata 



Others have no close relative on this continent, but may have 

 the same origin as some Old World plants. A list of these is here 

 given with the nearest relatives abroad. 



