84 Rydberg: Notes on Rosaceae 



soniana were proposed as new, and P. crinita and P. Lemmoni 

 were transferred from the Leucophyllae group. 



Potentilla klamathensis is related to P. millefolia and P. Hick- 

 mani, but differs in the long, ascending, at last spreading pubes- 

 cence. Dr. Wolf cites a specimen under P. millefolia, from Goose 

 Lake. This is perhaps Cusick's specimen cited below, as P. 

 millefolia is unknown outside of California. The following speci- 

 mens belong to P. klamathensis: 



Oregon: Fort Klamath, Aug. 7, 1894, Leiberg 660; Swan Lake, 

 Klamath Co., 1896, Applegate 167; Goose Lake Valley, Aug. 19, 

 1 90 1, Cusick 2768. 



Potentilla versicolor resembles P. plattensis in leaf form, but 

 the younger leaves are tomentose as well as strigose, and the pedi- 

 cels are erect or ascending, not arcuate-spreading in fruit. The 

 species is therefore more closely related to P. ovina and P. wyo- 

 mingensis, but is distinguished by the tomentum. It is known 

 from the type locality only. 



Potentilla Nelsoniana is based on P. pinnatisecta A. Nels.,* 

 as to the description and specimens distributed by Professor Nelson. 

 He adopted the name from P. diversifolia var. pinnatisecta S. 

 Wats.f An examination of Watson's type shows that it is the 

 same as P. ovina J. M. Macoun.£ Dr. Wolf makes it a variety of 

 P. plattensis, stating: "I have tried for long time but in vain, to 

 find on specimens received from the author of the species (Mr. 

 Aven Nelson) himself characters specifically distinctive from 

 P. plattensis. ... In the organs of the flowers as well as in all 

 other important points, one can find between P. plattensis and 

 P. pinnatisecta even with the microscope no distinctions which 

 warrant a specific distinction . " Both Professor Nelson and myself 

 have studied the plants in the field. The main distinctions are 

 as follows : P. plattensis has a deep taproot with a short perennial 

 crown branching just at the surface of the ground and sending out 

 numerous, decumbent, or rarely ascending, leafy stems, with 

 numerous flowers on pedicels which at least in fruit are arcuate- 

 spreading. In both P. Nelsoniana and P. ovina there is a distinct 



*Wyo. Exp. Sta. Bull. 28: 104. 1896. 

 tBot. King's Exp. 87. 1871. 

 J Can. Rec. Sci. 6: 464. 1896. 



