[From the Bulletin of ihk 1'okrby Botanical Club, 37 : 487-50.'. 1910.] 



Notes on Rosaceae — IV 



Per Axel Rydberg 



POTENTILLA {continued)* 



Permolles 

 This group contains only one species, PotentiUa pernwUis 

 Rydb. Dr. Wolf reduced this to a variety of P. Bias dike ana , 

 evidently without having seen any specimen. It has a pubescence 

 wholly unlike any species in the Graciles or the Nuttalliaxae 

 groups, and although somewhat related to these, I regard it as 

 distinct enough to be placed in a group by itself. Piper, who is 

 rather conservative in his treatment, regards it as distinct in his 

 Flora of Washington, f and cites three specimens. 



Candidae 



This group contains six species, of which four are proposed as 

 new. These are PotentiUa Elmeri, P. Pectcn, P. subvillosa, and 

 P. comosa. Of these, the last one is related to P. Bakeri, and the 

 rest to P. Candida. PotentiUa Pecten stands nearest to that species 

 and differs mainly in the leaves, which are green above, and in the 

 stem, which bears only a few small leaves. The following speci- 

 mens belong to P. Pecten: 



Montana: Bridger Mountains, 1897, Rydberg & Bessey 



4377- 



Wyoming: Cokerville, 1898, Aven Nelson 4647; Union Pass, 



A ven Nelson Q4J. 



*See Bull. Torrey Club 37: 375-386. 

 fContr. U. S. Nat. Herb. vol. n. 



487 



