362 Rydberg: Notes on Rosaceae 



SIBBALDIA, SIBBALDIOPSIS, AND DASIPHORA 



No essential change has been made in the treatment of these 

 genera since the publication of my monograph of 1898. 



DRYMOCALLIS 

 This genus is exceedingly perplexing as to its numerous and 

 somewhat intcrgrading forms. It is by no means easy to draw 

 specific lines. As represented in the eastern United States it is 

 easily disposed of, as it is there represented by only one species, 

 D. agrimonioides (Potentilla arguta Pursh). In the Rocky Moun- 

 tain region there are at least nine forms which I have regarded as 

 species, and these increase to about two dozen in the Pacific 

 States. In the North American Flora there were admitted in 

 all 28 species. Of these the following were proposed as new: 

 Drymocallis corymbosa, D. foliosa, D. pumila, D. viscosa, D. 

 arizonica, D. amplifolia, D. oregana, D. laxiflora, D. albida, and 

 D. micropetala. Besides these, D. glandidosa monticola and D. 

 glandulosa incisa w T ere raised to specific rank and the name D. 

 agrimonioides (Pursh) Rydb. was substituted fori?, arguta (Pursh) 

 Rydb., as Geum agrimonioides both has page priority and was 

 based on the typical form. 



Drymocallis corymbosa was described from specimens included 

 in D. convallaria in my Flora of Montana. It differs from the 

 original D. convallaria in the flat-topped instead of racemiform 

 cyme, the rounded-obovate instead of rhombic-obovate leaflets, 

 and the conspicuously long-hairy stem and petioles. 



It is common from Alberta to Colorado, Idaho, Washington, 

 and British Columbia. 



Drymocallis foliosa was described from specimens which I had 

 formerly determined doubtfully as D. glutinosa Rydb., i. e., D. 

 valida (Greene) Piper. It is characterized by its large-leaved in- 

 florescence and its rhombic-obovate coarsely and incisedly toothed 

 leaflets. The following specimens belong to it: 



Montana: Bridger Mountains, 1896, Flodman 5Q6. 



Wyoming: Buffalo Fork, 1897, Tweedy 214; Encampment, 1901, 

 Tweedy 4148. 



Utah: Alta Mountains, 1899, M. E. Jones 1108. 



