196 Rhodora [NovEMBER 
show rosulate basal leaves, while of the 210 individuals in the Gray 
Herbarium from Scandinavia, Siberia, Alaska, and from Greenland 
to Newfoundland and the Magdalen Islands fully one-third lack such 
rosulate foliage; and, incidentally, the Gmelin plate shows the original 
Siberian material naked at base. Although, as already stated, the 
plant of Colorado and Wyoming, as well as of Alberta and Manitoba, 
is inclined to be taller and more fastigiate and to have more slender 
leaves and calyx-segments than most other material, it would be 
most difficult to distinguish plants from Como, Colorado (coll. Hughes) 
with lanceolate leaves from Gmelin's plate or from many specimens 
from Labrador, Anticosti or Gaspé, while the more extreme Rocky 
Mountain plant is well matched by a specimen sent out by Besser 
from Irkutsk on the Angara River entering Lake Baikal in Siberia. 
The occurrence of this extreme form with linear leaves near the mouth 
of Angara River is significant, since Gmelin, who illustrated a broader- 
leaved individual, said of the original collection of P. rotata “Planta 
haec in palustribus ad ANGARAE fluvui ostium in lacum Baical et 
deinceps Bargusini occurrens" (Gmel. l. c. 112). In other words, 
P. fontana, although the more general form in the Rocky. Mountains, 
is also found in the type-region of P. rotata. The anthers of many 
Colorado specimens are longer than those of many maritime or more 
boreal plants, but some Colorado plants show small anthers; and 
some plants from about the Gulf of St. Lawrence, differing in no other 
character from the plants with small anthers, have anthers quite as 
long as in the more extreme Rocky Mountain individuals. The 
writer is, therefore, unable to keep apart even varietally the Rocky 
Mountain plant. 
Nelson (and others before him), in supposing Pleurogyne rotata (or 
Lomatogonium rotatum) “to skirt the northern boundary of the conti- 
nent, from Labrador and Greenland to Alaska," makes a considerable 
assumption. Outside Colorado and adajcent Wyoming the species 
is definitely known in America from southwestern Greenland, south- 
eastern Labrador, Newfoundland and eastern Quebec (south to the 
Magdalen Islands); on the southwest shores of Hudson Bay in Kee- 
watin, thence locally across Manitoba and Saskatchewan to Alberta, 
and somewhere on the Mackenzie; and from southern and western 
Alaska into Siberia. In other words, we have no definite knowledge 
that L. rotatum skirts “the northern boundary of the continent from 
Labrador...to Alaska," for east of an indefinite station on the Mac- 
