OCT., 1899.] PLANTS. 1 65 



Arnica merriami Greene.' 



Coninvoii in the lieatlier meadows and along the edges of streams in 

 most parts of the Hndsonian zone. This new species has just been 

 described by Professor Greene from specimens collected by us on the 

 moist banks of the small west arm of Upper Hquaw Creek, under the 

 alpine hendocks, where it is very common. 



Arnica longifolia D. C Eaton. 



Common in moist places in the Canadian zone, chiefly on the banks 

 of streams. (Identified by Professor Greene.) 



Arnica viscosa (xray. 



This singular species, which differs strikingly in appearance and 

 habit from most members of its genus, grows in dense patches, usually 

 2 or 3 feet in diameter, among the bare lava rocks on steep sloi)es near 

 timberline. On the south side of Shasta it was fairly common and 

 flowering abundantly in August. (Identified by Miss Eastwood.) 



Artemisia tridentata Nutt. True Sagebrush. 



Sagebrush is unknown in the region about Shasta except in Shasta 

 Valley, which it invades and overspreads from the Klamath country 

 on the north. It reaches the extreme south end of Shasta Valley and 

 penetrates a short distance into the bordering forest of ponderosa pines, 

 where it mixes with Kunzia tridentata. Pushing southeasterly over 

 Shasta Valley it reaches the gap at Sheep Rock. Its zone position is 

 Upper Sonoran and Transition. 



Artemisia ludoviciana Nutt. 



A foTmoi Artemisia ludoviciana is common in places just below Wagon 

 Camp, along the upper edge of the Transition zone. When the species 

 aiul subspecies now lumped under the above name are properly defined, 

 several useful zone plants may be added to their appropriate lists. 



Machaeranthera shastensis Gray. Shasta Alpine Aster. 



[^ Aster sltastensis Auct.]. 



A dwarf alpine species abounding on the bare rocky pumice slopes 

 in the neighborhood of timberline, and common also on the borders of 

 the heather beds iu the glacial meadows. This is the type form. A 

 related but unnamed form, usually a foot and a half or more in height, 

 is common and widely distributed on the lower slopes, chiefly in the 

 upper part of the Transition and lower part of the Canadian zones. 



Oreastrum alpiginum (Gray) Greene. 



Common in the neighborhood of timberline, particularly in moist 

 places. (Identified by Professor Greene.) 



' Pittonia, IV, p. 36, March 17, 1899. 



