MACKENZIE: NOTES ON CAREX 
Lower bracts leaflet-like, much exceeding head. 
Perigynia obscurely nerved ventrally, the beak 
ferruginous at orifice, bidentate. 
Perigynia strongly ne . ventrally, the beak 
hyaline at orifice, bidentulate. 
Lower bracts scale-like, ae aca than or slightly 
exceeding head. 
Perigynia flat, except where distended by achenes 
about equally in front and behind. 
Perigynia strongly plano-convex. 
Perigynia’2.25-3.5 mm. in length. 
Margins of perigynia entire (or very ob- 
scurely subserrulate). 
Margins of perigynia strongly serrulate. 
Head stiff; culms stiff, smooth; leaf- 
blades averaging 2.5 mm. in width, 
light green 
Head nodding; culms very slender, 
roughened above; leaf-blades averag- 
ing 1.5 mm. in width, deep green. 
Perigynia 3.5 mm. or more in length. 
Perigynia beaks at tip and scales brownish 
or blackish tinged. 
Perigynia beaks at tip and scales reddish or 
Paget itis ripe 
ce PG 4 
lovee bracts at least strongly phates 
tant. 
sieges and scales strongly reddish 
ed; lower bracts not strongly 
ae tant. 
(*) Perigynia with thick firm walls. 
Perigynia strongly few- to several- 
nerved dorsally 
Perigynia nerveless or very 
nearly so v 
Spikes say capitate 
blades averaging 
wide; culms 3.5-12 es, 
hi 
Spikes not capitate, the 
head slender; blades 
averaging 1.5-2 mm 
wide; culms 1-5 dm. 
high 
gh. 
Culms slender; leaves 
ce) 
twenty perigynia. — 
603 
C. athrostachya. 
C. tenuirostris. 
C. microptera. 
C. integra. 
C. subfusca. 
C. teneraeformis. 
C. olympica. 
C. amplectens. 
C. sub-bracteata. 
C. gracilior. 
