ocr., 1899. ] PLANTS. 165 
Arnica merriami Greene.! 
Common in the heather meadows and along the edges of streams in 
most parts of the Hudsonian 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 Squaw Creek, under the 
alpine hemlocks, where it is very common. 
Arnica longifolia D. C. Katon. 
Jommon in moist places in the Canadian zone, chiefly on the banks 
of streams. (Identified by Professor Greene.) 
Arnica viscosa Gray. 
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 slopes 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. 1t reaches the extreme south end of Shasta Valley and 
penetrates a short distance into the bordering forest of ponderosa pines, 
where it mixes with NKunzia 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 formof Artemisia ludoviciana is common in places just below Wagon 
Camp, along the upper edge of the Transition zone. When the species 
and subspecies now lumped under the above name are properly defined, 
several useful zone plants may be added to their appropriate lists. 
Macheranthera shastensis Gray. Shasta Alpine Aster. 
[=Aster shastensis 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 in 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. 
