3 
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. /encophylla, which does not ap- 
pear there. The Kew Index has also omitted P. /encophylla, 
which should take the place of P. Hippiana, being a year older, if 
it were not for the fact that it very likely is to be explained as a 
misprint. 2. Hippiana is sometimes very hard to distinguish 
from P. effusa, 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 soilthan P. efusa. It extends 
from New Mexico and Arizona to Minnesota and Saskatchewan. 
_»~ POTENTILLA HIPPIANA PROPINQUA DN. n. 
Fotentilla diffusa A. Gray, Mem. Am. Acad. 1849: 41. 1849. 
Not Willd. 
Potentilla Hippiana pulchenima §. Wats. Proc. Am. Acad. 
555, in part, 1873. Not P. pulcherrima 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. pulcherrima, which is a much taller plant. 
POTENTILLA AMBIGENS Greene, Erythea, 1: 4. 1893. 
It is strange that this very marked species should not have 
been described before 1893. It was collected by Hall and Har- « 
bour in 1862, Wm. A. Bell in 1867 and Geo. Vasey in1881. The 
first specimens were included by Dr. Gray in P. Hippiana. On 
the label of Bell’s specimens is written: “Durand suggests P. 
vwularis. Gray says no!—perhaps P. campestris.’ One of Dr. 
Vasey’s specimens is labeled Porentilla Thurberi,by 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 inlet, u 
_ Specimens have been examined: ee | 
