MACKENZIE: NoTEs ON CAREX—XII 365 
~ ing to his previous publications concerning its distinguishing 
characters or range; and this treatment is followed by Kiikenthal 
in the Pflanzenreich (4%°: 209). By other authors Professor 
Bailey’s name has been treated as a synonym of Carex albo- 
lutescens.* 
As shown however by the large number of specimens of 
Bailey’s variety which have been collected in recent years, it 
not only has an entirely different range from Carex albolutescens 
but it has several constant and well-marked points of difference, 
and is clearly entitled to specific rank. It is a northern species 
ranging from Saskatchewan to New Brunswick and south to 
Massachusetts, Connecticut and northern Pennsylvania. It 
occurs in a great variety of habitats varying from wet to dry, but 
seems able to thrive in much drier places than can Carex 
albolutescens. In the southern part of its range it seems only 
to be recorded from the higher elevations. It is not a coastal 
plain plant like Carex albolutescens, but like that species is not 
a species of limestone areas. 
As above stated Carex albolutescens is typically a coastal 
plant. It reaches its northern limit in eastern Massachusetts 
but has a very extensive range to the south, being found as 
far south as northern South America. In the more southern 
part of its range it gets into the mountains. 
The best technical character to separate the northern plant 
from Carex albolutescens is that in it the perigynia are nerveless 
ventrally, while in Carex albolutescens they are strongly several- 
nerved. But in addition to this the spikes are numerous (five 
to thirty) and densely aggregated; the green perigynia are more 
conspicuous than in Carex albolutescens, thus giving the heads 
a characteristic heavy, green, or in age brownish, appearance; 
the sheaths are looser, and the leaf-blades of the sterile culms 
are usually wider, being 4-5 mm. in width; in developed plants 
the lateral spikes also are truncate-rounded at base. 
Carex albolutescens has fewer spikes (three to ten), which 
are less densely aggregated; and the heads have a very character- 
istic silvery-green appearance; its sheaths are tighter than in 
the northern plant and the leaf-blades of the sterile culms are 
*The perigynium and the heavily spiked head, figured in the seventh 
edition of Gray’s Manual (f. 351) as Carex albolutescens, represent Bailey’s 
plant, and the head with five spikes represents genuine Carex albolutescens. 
