Fernald and Long,— Variations of Potentilla palustris 7 
*the more common American form (C. angustifolium Raf.)," with 
leaflets “linear-oblong,” extends “south to New England, Minnesota, 
Wyoming, and California"; thus seeming to indicate that the com- 
mon American plant has recognizably narrower leaflets than the 
European. In their study of this species, however, the writers have 
been unable to make out any definite difference in the shape of leaflets 
to separate from the European plant the common plant of southern 
British America and the Northern States, which extends southward 
at least to New Jersey, Pennsylvania, Ohio, Indiana, Illinois, Iowa, 
Wyoming and California. In the plant of Europe (fig. 1) the leaflets 
are, of course, variable in size and form, but they have in general an 
oblong-lanceolate to oblanceolate outline, and the various Eurasian 
specimens are readily matched by specimens from Canada and the 
northern United States. In the Eurasian plant the terminal leaflet 
of the primary leaves varies (in a rather small series of specimens 
examined) from 2-7 (average 4) cm. in length, though some of the 
European plates show that they may be longer. In a much larger 
American series the common plant has the terminal leaflet ranging in 
length from 2-10 (av. 5.2) em. In the Eurasian plant the terminal 
leaflet ranges from 0.9-2.7 (av. 1.6) em. wide, in the American from 
0.7-3.8 (av. 1.8) em. wide. Expressed as a proportion, the breadth of 
the terminal leaflet in the Eurasian plant is 4453 as great as the length; 
in the common American plant the terminal leaflet is $—3 as broad as 
long, but it should be noted that the plants with narrowest leaflets 
come for the most part from the West — Montana, Washington, 
Oregon, etc. and are undoubtedly the extreme which was separated 
by Rafinesque as Comarum angustifolium (fig. 2). Similar plants 
with the leaflets only $ as broad as long are found at scattered points 
eastward and the variant seems to be merely an extreme of the series 
rather than * the more common American form," for as already stated, 
the majority of American specimens seem to the writers quite in- 
separable from the Eurasian material. 
The small-leaved plant of Labrador and Alaska (and the islands of 
northeastern Asia), however, which Rafinesque separated as Comarum 
angustifolium, var. parvifolium and which Rydberg identifies as the 
typical form of Comarum palustre, impresses us as sufficiently distinct 
for varietal recognition. The characters emphasized by Rafinesque, 
the small cuneate or elliptic leaflets and the few flowers (“branches 
uniflore"), seem to be reasonably constant in nearly all plants from 
