432 RyYvBERG: Rocky MounrAIN FLORA 
~~ but with narrower leaves than either. A. pudica Rydb. is re- 
lated to A. gnaphalodes and A. diversifolia, but in my opinion 
distinct. This is, of course, a matter of individual opinion. A. 
Purshiana is a northern plant with much broader leaves and denser 
inflorescence than the ordinary A. gnaphalodes. It is common 
in British America and Montana, has been collected in the Da- 
kotas, and one specimen from Nevada I have referred doubtfully 
here, but I have seen no specimens from Wyoming or southward. 
Perhaps this species is unknown to Professor Nelson. 
I must protest, however, against the reduction of Artemisia 
candicans Rydb., and A. floccosa Rydb. to synonyms of A. gnaph- 
alodes. Artemisia floccosa, as stated above, should take the place 
of A. paucicephala and A. gracilenta, and the A. candicans is re- 
lated to it. Using Nelson’s key, one would place it in A. pauci- 
cephala, but the heads are still broader, sessile in small clusters, 
nodding or spreading, instead of erect, and the tomentum is more 
loose. , 
Artemisia Underwoodii Rydb., A. Brittonii Rydb. and A. 
latiloba (Nutt.) Rydb. are made synonyms of A. ludoviciana 
Nutt. I doubt if Professor Nelson knew what the first two 
are. One specimen of A. Underwoodii, viz., Goodding 1034, 
was distributed from the University of Wyoming under the 
name A, silvicola G.E.O. Both A. Underwoodii and A. silvicola 
are perhaps more closely related to A. mexicana than to A. lu- 
doviciana. 
Artemisia Brittonii Rydb. has the leaves permanently tomen- 
tose on both sides and would be placed in A. gnaphalodes if Nelson's 
key were used. It is most nearly related to A. Purshiana, but 
has at least the lower leaves deeply lobed. 
Artemisia latiloba (Nutt.) Rydb. should be known as A. 
Hookeriana Besser. I have seen a duplicate of the latter in the 
Gray herbarium and there is no doubt that it is the same as my 
A. latiloba. It isa northern plant, not found in Wyoming and 
rare in Montana. It has the same leaf-form as A. elatior and A. 
Suksdorfii, but the inflorescence is denser and the involucre 
is densely tomentose. It is sometimes hard to distinguish from, 
and in the west seem to grade into, what has been known in Cali- 
fornia and Nevada as A. heterophylla Nutt. The latter name is 
+ ae a 
Noe AS Brey 
