American Botany. Watson in his Bibliographical Index has no 

 reference to any of the editions of Eaton's Manual and gives Eaton 

 & Wright as a reference under P. lcHcophylla,vi\\\ch. does not ap- 

 pear there. The Kew Index has also omitted /-". IcneopJiylla, 

 which should take the place of P. Hippiaiia, being a year older, if 

 it were not for the fact that it very likely is to be explained as a 

 misprint. P. Hippiana is sometimes very hard to distinguish 

 from P. eficsa, and the two seem to grade into each other. P. 

 Hippiana is, however, as a rule larger, silky as well as tomentose ; 

 the branches are more erect and the bractlets nearly equalling the 

 acute sepals. The species grows on the plains and the foot hills of 

 the Rockies, but generally in richer soil than P. effusa. It extends 

 from New Mexico and Arizona to Minnesota and Saskatchewan. 



POTENTILLA HiPPIANA PROPINQUA n. n. 



Potcntilla diffusa A. Gray, Mem. Am. Acad. 1849: 41. 1849. 

 •Not Willd. 



Potentilla Hippiana piilclicnima S. Wats. Proc. Am. Acad. 

 555, in part, 1873. Not P. piilcherrinia Lehm. 



The stem is more diffuse or ascending, rather low ; the leaflets 

 are more approximate and more silky, scarcely at all tomentose, 

 often green above. In the latter case they resemble somewhat 

 those of P. piilcJierrinia, which is a much taller plant. 



Potentilla AMBiGENS Greene, Erythea, I : 4. 1893. 



It is strange that this very marked species should not have 

 been described before L893. It was collected by Hall and Har- 

 bour in 1862, Wm. A. Bell in 1867 and Geo. Vasey in 1881. The 

 first specimens were included by Dr. Gray in P. Hippiana. On 

 the label of Bell's specimens is written: " Durand suggests P. 

 rivularis. Gray says no! — perhaps P. cainpestris." One of Dr. 

 Vasey's specimens is labeled Potentilla Thurberi,hy whom I do 

 not know. 



P. ambigens is the tallest of the group, 6-7 dm. high, rather 

 sparingly grayish silky. The leaflets are 3-4 cm. long, coarsely 

 serrate and more or less decurrent on the rachis. The following 

 specimens have been examined: 



