Carex Cyperaceae 215 



Perigynia finely and closely ribbed 37. § Pseudo-Cyperi, p. 263. 



Perigynia coarsely ribbed. 

 Perigynia subcoriaceous; foliage or perigynia or both sometimes pubescent. 



38. § Paludosae, p. 264. 



Perigynia membranaceous; foliage and perigynia not pubescent (except peri- 

 gynia sometimes hispidulous in C. Grayii of § Lupulinae). 

 Perigynia obconic or broadly obovoid, truncately contracted into a long subu- 

 late beak 39. § Squarrosae, p. 266. 



Perigynia from lanceolate to ovoid or globose-ovoid, not truncately contracted. 



Perigynia 7-10 mm long; achenes 2-3 mm long, 1.25-2.5 mm wide 



40. § Vesicariae, p. 267. 



Perigynia 10-20 mm long; achenes 2.5-6 mm long, 2-4 mm wide 



41. § Lupulinae, p. 269. 



ARTIFICIAL KEY TO THE SECTIONS OF INDIANA CARICES 



Spike one. 



Perigynia strongly inflated, sessile or nearly so, not becoming reflexed; pistillate 



scales persistent 39. § Squarrosae, p. 266. 



Perigynia not inflated. 



Pistillate scales not foliaceous; perigynia not abruptly beaked. 



Pistillate scales deciduous; perigynia stipitate, at least the lower reflexed at 



maturity 35a. § Orthocerates, p. 263. 



Pistillate scales persistent; perigynia not reflexed. 



Perigynia rounded at the apex ; spike androgynous 



12. § POLYTRICHOIDEAE, p. 237. 



Perigynia abruptly tapering to a pointed, slightly bidenticulate apex; spike 



entirely staminate or pistillate 16. § Pictae, p. 243. 



Lower pistillate scales foliaceous; perigynia abruptly beaked 



13. § Phyllostachyae, p. 238. 



Spikes more than one. 



Stigmas two; achenes lenticular. 



Lateral spikes sessile, short; terminal spike usually androgynous or gynaecan- 

 drous. (Vignea.) 

 Culms arising singly or few together from long-creeping rootstocks; perigynia 

 not subterete. 

 Heads elongate, 2-7 cm long; culms not branching; perigynia thin- or wing- 

 margined; not plants of sphagnum bogs. 

 Perigynia thin- but not wing-margined, ovate orbicular, thick-plano-convex, 



3-4.5 mm long; spikes all androgynous; plants of wet habitats 



1. § Intermediae, p. 218. 



Perigynia narrowly wing-margined, oblong-lanceolate, plano-convex, 4.75-6 

 mm long; lowest spikes usually pistillate, the middle staminate, and 



terminal androgynous ; plants of dry sandy habitats 



2. § Arenariae, p. 218. 



Heads ovoid, 0.5-1.2 cm long; culms becoming decumbent and branching; 

 perigynia neither thin- nor wing-margined, oblong-obovate, thick-plano- 

 convex, 2.5-3.75 mm long; plants of sphagnum bogs 



3. § Chordorrhizae, p. 219. 



Culms cespitose, the rootstocks occasionally somewhat prolonged with short inter- 

 nodes but not long-creeping (except occasionally in C. disperma of § Heleon- 

 astes which has subterete perigynia). 

 Spikes androgynous, many-flowered; perigynia not subterete. 



Perigynia abruptly contracted into the beak; culms not flaccid and not 

 flattening in drying. 



Spikes few (generally 10 or fewer) , usually greenish 



4. § Bracteosae, p. 219. 



