Rydberg : Notes on Rosaceae 499 



In neither case did I find a single specimen that could be referred 

 to P. nivea. At the Colorado station it was associated with P. 

 saxinwntana and P. uni flora, but was easy to distinguish, especially 

 from the latter. In the collections at the New York Botanical 

 Garden there are eighteen sheets of P. quinquefolia, representing 

 sixteen localities. I have seen perhaps as many more localities 

 represented in other herbaria, and have seen no sheets on which 

 it was mixed with P. nivea proper. We have only four sheets of 

 P. nivea from the Rocky Mountain region. When I visited Copen- 

 hagen in 1901, I confused P. rubricaulis with it and named a 

 specimen of the latter P. snbquinata. This was due mostly to 

 the fact that I had a wrong idea of P. rubricaidis Lehm. and had 

 applied the latter name to what appears in the North American 

 Flora as P. rubripes Rydb. Dr. Simmons has cleared up P. 

 rubricaulis Lehm. in such a way that nothing more needs to 

 be said, except perhaps that he could have made plainer the dif- 

 ferences between the trifoliolate P. rubricaulis var. arctica and 

 • P. nivea L., taken in such a broad sense as Dr. Simmons has done. 

 Of the specimens collected by Pedersen and referred to P. sub- 

 quinata by me, no. 496, as represented in the New York Botanical 

 Garden herbarium, is a form of P. nivea L., with some quinate 

 leaves. It is intermediate between P. nivea macrophylla and P. 

 nivea snbquinata. Nos. 113 and 233 belong to P. nipharga Rydb., 

 which also sometimes has quinate leaves. The other numbers 

 are not represented here. There is none referable to P. quinque- 

 folia, which seems confined to the Rocky Mountains of the United 

 States and Northwestern Canada. 



Closely related to P. quinquefolia, perhaps a depauperate 

 variety thereof, is P. modesta Rydb., described as new in the North 

 American Flora. It is confined to two mountain chains in Utah. 

 It differs from P. quinquefolia, besides in the smaller stature, in 

 the linear and obtuse instead of lanceolate and acute bractlets, 

 the golden yellow petals only 4 mm. long, and the dense inflores- 

 cence, reminding one of that of P. Hookeriana. The following 

 specimens belong to it: 



Utah: Mount Barrette, July 26, 1905, Rydberg & Carlton 

 7261, 7259, and 7258; Sierra La Sal, 1899, C. A. Purpus G, Q, 

 and R. 



