62 



CONTEIBUTTONS FROM THE NATIONAL HERBARIUM. 



Distrihtil ion (if rliiirurtrrixl ic II iKlsonid ii siiecies — C'(jntiiiiiecl. 



THE ARCTIC ZONE. 



This is sharply iiinrkcHl by the high altitude timber line. As before 

 explained, this line extends to a much higher altitude, TOO meters 

 or more on Mount Rainier, on the ridges than, in the draws between. 

 This, in general, is true of all the northweslern mountains. On the 

 highest mountain peaks flowering plants extend \\p to 3,200 meters 

 (10,500 feet) altitude. The lower portion of this zone, except 

 where there are rock outcroppings,. is covered with a dense carpet of 

 grasses and flowers. Among the more abundant of the former are 

 Festuca viridifla, Poa arctica, and Agrostis rossae. Among the more 

 conspicuous flowers in the damper places are a buttercup {Ranun- 

 culus suksdorfii), a marsh marigold {Caltha leptosej)ala) ^ and a shoot- 

 ing star {Dodecatheon 'je-jfreyi). On the drier slopes Pidsatilla occi- 

 den tab's raises its curious tasseled heads of akenes; a lupine {Lupinus 

 subalpini/s) forms great masses of blue; a painted cup {Castilleja 

 oreojjola) makes mats of dull crimson, and a cinquefoil {Potentilla 

 faheJJifoJla) furnishes an abundance of yellow. Even more con- 

 spicuous are the two ''■ heathers," PhyUodoce emjyetrifonnis and 

 Cassiope mcrfeyisiana^ the former with clusters of rose-j)urple flowers, 

 the latter with the clusters pure white. 



Along the rills a beautiful blue gentian {Gentiana cahjeosa), the 

 crimson mimulus {Mhnulus lewisii), and the yellow arnicas make 

 parti-colorecl borders. 



Two small- plants, a saxifrage {Saxifruya foh/iic/) and Luthea 

 pectinata are conspicuous only because they form dense mats. 



