472 Rydberg: Phytogeographical notes 



Scirpus pauciflorus Swertia pajustris 



Scirpus caespitosus *Pyrola idiginosa 

 Bistorta bistortoides Veronica Wormskjoldi 



Bistorta vivipara *Elephantella groenlandica 

 Ranunculus affinis Amarella scopulina 



Thalictrum alpinum Amarella strictiflora 



Vaccinium oreophilum Antennaria nardina 

 Primula Parryi 



To this formation belong also the following species restricted 

 to a part of the region: 



Southern Northern 



Caltha rotundijolia Caltha leptosepala 



Ranunculus stenolobus Caltha Cheledonii 



*Senecio atratus 

 Ligusticum Porteri 



Willow bogs 



These willow bogs are not exclusively alpine, as most of the 

 species there are found also in the subalpine region. They are not 

 so common in the southern Rockies as they are in the northern. 

 In Colorado, the shrubby species consist mostly of Salix glaucops 

 and Betula glandulosa, although other species of willows, as for 

 instance S. chlorophylla, are not rare. Kalmia microphylla is very 

 local there. In the northern Rockies the number of species is 

 increased. More species of Salix are found and S. chlorophylla 

 becomes more predominant. Alnus sinuata is added to Betula 

 glandidosa. Sometimes, especially in pockets on the northern 

 slopes, the predominant plants are ericaceous, viz., Kalmia 

 microphylla, Ledum glandulosum, Phyllodoce empetriformis , and 

 P. glanduliflora. In the Canadian Rockies evidently are added 

 to these, Arctuos and Oxycoccus. The herbaceous plants are 

 mostly the same as in the sedge bogs, Elephantella and Pyrola 

 tdiginosa being conspicuous, especially in the subalpine regions. 



The shrubby plants characteristic of the willow bogs are the 

 following: 



Salix chlorophylla Salix saximontana 



Salix glaucops Salix monticola 



