RYDBERG: NOTES ON ROSACEAE 493 
with hesitation, the specific rank of these forms, on which Erythro- 
coma canescens Greene was based. 
Steversia ciliata (Pursh) G. Don. This species is confined to 
the Rocky Mountains and running down into the Cascades of 
Washington. It is found neither on the plains nor in the Sierra 
Nevadas. In most of its range it is associated with S. grisea and 
intermediate forms are not lacking; they are perhaps to be ex- 
plained as of hybrid origin. The center of its distribution is in 
the northern Rockies, while that of S. grisea is more common in 
the southern. Its range barely touches that of S. ¢riflora and 
only slightly overlaps that of S. canescens. 
Sieversia flavula (Greene) Rydb. It was only with reluctance 
I admitted this as a species in the North American Flora. It is 
rather local in the mountains of Wyoming and Montana. The 
following specimens have been seen. 
Wyominc: A. Nelson 829, 7501. 
Montana: Chestnut & Jones 105; Rydberg & Bessey 4414. 
Sieversia brevifolia (Greene) Rydb. This is a derivative of 
S. ciliata. It is confined to the mountains of central Utah. S. 
Watson 318, doubtfully referred here by Dr. Greene, I think should 
be referred to S. ciliata. The following specimens belong here: 
Uran: Panguitch Lake, Jones 6002g; Fish Lake, Jones 57792, 
54410; L. F. Ward 378. 
Sieversia Peckii (Pursh) R. Br. This and the three following 
form a distinct natural group, which is represented in Europe by 
Sieversia montana and other species. S. Peckii has been confused 
with S. radiatum or has been made a variety of the same. It is, 
however, perfectly distinct. It is confined to the mountains of 
New Hampshire and Maine. : 
Sieversia radiata (Michx.) R. Br. This is closely related to 
the northwestern S. calthifolia (Menzies) D. Don. It is con- 
fined to the region of which Roan Mountain is the center, and the 
majority of the specimens in our herbaria are from that very 
mountain. 
Sieversia calthifolia (Menzies) D. Don. This species is rather 
variable. In the high arctic regions it becomes stunted and more 
hairy (var. congesta), and then has a quite different appearance. 
Another cause for the many synonyms cited under the species 
