1922] Fernald & Weatherby,—Varieties of Geum canadense 47 
VARIETIES OF GEUM CANADENSE. 
M. L. FERNALD AND C. A. WEATHERBY. 
As anyone who has critically examined any considerable series of 
specimens must be aware, Geum canadense Jacq. is a variable species. 
Rydberg (N. Am. Fl. xxii. pt. 5: 403 (1913) ) has segregated two of its 
forms as species; but had he seen material from a wider range his 
conclusions might have been different. Far from being, as he states, 
confined to the prairie region, his G. camporum, or a plant answering in 
all respects te’*“°'description, is apparently the commonest form of 
the group as far east as central New York and, beyond that, occurs 
in considerable quantity in northern and eastern Maine, New Bruns- 
wick and Nova Scotia, in eastern Massachusetts and rarely at scat- 
tered stations elsewhere in New England. Two of the characters— 
the shape of the petals and the length of the upper internode of the 
style—which he uses to distinguish G. camporum from G. canadense, 
break down completely: indeed, so far as the latter is concerned, we 
have seen only one specimen, and that referable to what we here call 
var. texanum, in which the upper internode is short enough to fit the 
measurement, “scarcely 1 mm. long,” given by him for G. canadense. 
In all other characters G. camporum and G. canadense pass almost 
imperceptibly into each other: the former can hardly be kept up as a 
species by anyone who accepts the category of variety at all. G. 
Meyerianum Rydb. (G. agrimonioides C. A. Meyer) appears to be only 
an inconstant foliage form, its pinnate lower leaves occurring in indis- 
criminate combination with all other characters in the group, and to 
be unworthy of any recognition. 
As understood by the writers, G. canadense exhibits six recognizable 
trends, which may be distinguished as follows: 
a. Upperinternode of the style conspicuously, though sparsely, 
bearded with stiff white hairs; body of the carpel ipae E 
sparsely appressed-pubescent as well as hispid with long 
setae: outer surface of sepals, petioles and stems with at 
least a few long hairs, or the stems sometimes glabrate. b. 
b. Flowers and fruiting heads with 30—60 carpels; these, 
when mature, with mostly broadly ovate to obovate 
bodies 2.5-3 mm. long: peduncles (except for the glands, 
when present) typically, but by no means always, finely 
puberulent only, or with a few, scattered tong hairs: 
leaves thin in texture; blades of the median cauline leaves 
5-10 em. long, rarely shorter, the terminal segment 
mostly acute. c. 
