CAREX 



(b) Lateral pistillate spikelets many-flow- 

 ered, cylindric, 2-8 cm. long 

 x. Beak conspicuously 2-toothed, the teeth 



often 1-2 mm long; stigmas 3 

 (x) Perigynia hairy 

 m. Perigynia 5-8 mm. long, tapering 

 gradually into a beak about as 

 long as the body; teeth spread- 

 ing, 1-2 mm. long C.aristdta 

 n. Perigynia 2-4 mm. long, abruptly 

 beaked, the beak about one-third 

 as long as the body; teeth less 

 than 1 mm. long C.lanuginosa 

 (y) Perigynia smooth 

 m. Staminate spike usually 1 ; scales 

 with a rough awn 2-4 times 

 longer than the ovoid base C. hystridna 

 n. Staminate spikes usually 2 ; scales 

 acute or with an awn not longer 

 than the lance-ovate base 

 (m) Perigynia spreading hori- 

 zontally at maturity, usually 

 2 mm. or less wide at base C. utriculdta 

 (n) Perigynia ascending, usually 



2.5-3 mm. wide at base C. monile 

 y. Beak minutely or not at all toothed 

 (x) Beak as long or longer than the 



body; stigmas 3 



m. Spikes brown, 1-2 cm. long; peri- 

 gynia densely crowded, lanceo- 

 late, tapering gradually into a 

 beak about as long as the body C. abldta 

 n. Spikes pale green, 2-5 cm. long; 

 perigynia often separate, round- 

 ish, abruptly narrowed into a 

 slender beak longer than the 

 body C. longirostris 



(y) Beak none up to one-third as long 



as body ; stigmas 2 as a rule 

 m. Perigynia inflated ; beak about as 



long as body C.saxdtilis 



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