1900] ROCKY MOUNTAIN HERBARIUM 203 
Arnica caespitosa.— Low (1~2°"), matted, sometimes forming 
beds several decimeters across, with moderately large woody 
horizontal rootstocks from which spring numerous thick fibrous 
roots, the whole forming a dense turf: the numerous stems 
erect, sparsely short-lanate as is also the base of the involucre: 
leaves nearly glabrous or sparsely ciliate-woolly, three or four 
pairs on the stems and some fascicled ones on the sterile 
‘rewns; crown leaves mostly oblanceolate, petioled, 4-7™ 
long (including the petiole); basal stem leaves very small 
(often wanting), obovate as also the next larger pair; upper 
leaves lanceolate : heads one to five, large for the size of the 
plant, mostly three (a terminal one and a pair from the upper- 
— axils); pedicels moderately stout, 2-5 long: involucres 
turbinate ; bracts linear-oblong, sub-acute, almost equaling the 
disk ; fays 8-10, ascending, rather broad: akenes linear, white- 
pubescent, about 5™" long, equaling the white, glistening pappus. 
rite eage ed of nearly alpine stations; occurring: in patches > 
dias ieee a Sa It may be recognized by its Ces pitose habit an 
whic bah , urbinate head (the rays are ascending also), and the 
pubescent akenes, 
Collections of it ar 
no. 6717, € no. 5785, Druid peak, Yellowstone park, July 12; 
Teton mountains, Aug. 16, 1899. 
Laramie, Wyo. 
