494 RypsBerc: Nores oN ROSACEAE 
madrensis is overlooked by Dr. Wolf. P. sanguinea is described 
as new in the North American Flora. 
AUREAE 
As treated in the North American Flora, this group contains 
nine North American species. If one follows Dr. Wolf in laying so 
much stress on the form of the style, all the American species, except 
Potentilla maculata and P. Langeana, should be excluded from the 
AuREAE group. In this group the styles should be somewhat 
thickened upward, instead of downward. In some species the styles 
are perfectly filiform, not thickened either way. The result is 
that a distinct line can not be drawn between the CONOSTYLAE 
and the GompHosTYLAE of Dr. Wolf’s monograph. In the 
Avureak, Dr. Wolf has such diverse species as Potentilla maculata, 
P. elegans, P. Robbinsiana, and P. gelida. Of these, P. Robbin- 
siana at least does not have the styles thickened upwards. The 
RANUNCULOIDES group of Dr. Wolf is still worse. It contains not 
only the thick-leaved and thick-rhizomed Mexican and Central 
American species, of which it was made up in my treatment, and 
my SUBVISCOSAE and BREVIFOLIAE groups, but also such diverse 
species as Potentilla acuminata Hall (related to P. saxosa), P. 
flabellifolia Hook., P. fragiformis Willd., P. Townsendii Rydb., 
P. Palmeri Th. Wolf, and P. Sierrae-Blancae Rydb. Potentilla 
emarginata Pursh is placed with the AUREAE, while the closely 
related P. fragiformis is placed in RANUNCULOIDES. P. gelida 
Mey. is put in the former, and P. flabelliformis Hook., which S, 
Watson and other students of Potentilla have not been able to 
distinguish from it, is put in the latter group; P. perdissecta 
Rydb. or, as Dr. Wolf calls it, P. diversifolia var. decurrens (Wats.) 
Th. Wolf, is placed in the MuttijuGAr, while P. Ranunculus 
Lange, which can be separated from it only by the different root- 
stock (see below), is placed in the RANUNCULOIDES. P. Town- 
send and P. Palmeri and their relationship I have discussed 
before. Dr. Wolf's grouping in this case therefore is very artificial 
and unsatisfactory. 
I think that the group as constituted by me is more natural, 
although it could be subdivided into three subgroups. Potentilla 
Sierrae-Blancae stands alone, is not so closely related to the rest, 
