CYPEEACEAE. 53 



XXX. LUPULINAE. 



Pistillate spikes globose or subglobose : style straight. 



Scales strongly awned : pistillate spikes 1-12-flowered : 



leaf -blades 2.5-7 mm. wide. 77. C. intumescens. 



Scales obtuse to slightly cuspidate: pistillate spikes 



6-30-flowered : leaf -blades 5-9 mm. wide. 78. C. Asa-Grayi. 



Pistillate spikes oblong or cylindric : style abruptly bent. 79. C. lupulina. 



1. C. retroflexa Muhl. Leaves mostly shorter than the culm; blades 1-2.5 mm. 

 in width: culms slender, 2-5 dm. tall: lower bract bristle-form: spikes 4-8, 

 subglobose, 4-10-flowered, the upper all close together: staminate flowers termi- 

 nal: scales ovate, acuminate, deciduous, about as long as the perigynia: peri- 

 gynia ovate, radiating or reflexed at maturity, about 3 mm. long, smooth, 

 compressed, but biconvex, corky-thickened at base, each tapering upwardly into 

 a 2-toothed beak about J the length of the body. M. Rather rare, in thickets. 

 Limestones. Spr. 



2. C. rosea Schk. Leaves soft; blades flat, 1-2.5 mm. wide or less, shorter 

 than the culm: culms slender or filiform, rough above, 3-7 dm. long: lower bract 

 1-6 cm. long: spikes 2-8, subglobose, 3-8 mm. in diameter, 2-15-flowered: 

 scales ovate-oblong, white-hyaline, obtuse or acutish, persistent, as long as the 

 perigynia: perigynia ovate-lanceolate, flattish, bright-green, radiately spread- 

 ing, nerveless, shining, 2-4 mm. long, each narrowed into a stout 2-toothed 

 roughened beak about i the length of the body. Common, in woods. Sum. 



3. C. Muhlenbergii Schk. Leaves usually shorter than the culm; blades 2-5 

 mm. wide, somewhat involute in drying: culms slender, erect, 3-angled, rough, 

 at least above, 3-9 dm. tall: bracts bristle-form, very short: spikes 4-10, ovoid 

 or subglobose, close together in an oblong head, the lower distinct : scales ovate- 

 lanceolate, rough-cuspidate or short-awned, narrower and about length of the 

 perigynia: perigynia broadly ovate-oval, 3 mm. long, strongly nerved to nearly 

 nerveless, ascending or spreading, each with a short 2-toothed beak. N. M. 

 Rather rare, on dry hillsides. Sandstones and shales, limestones. Spr. 

 and sum. 



4. C. cephalophora Muhl. Leaf -blades 2-4 mm. wide: culms slender, rough 

 above, 2.5-7 dm. tall: bracts of the lower spikes bristle-form: spikes few, sub- 

 globose, clustered in a short-oblong head 8-20 mm. long: scales ovate, rough- 

 cuspidate or awned, the body strongly exceeded by perigynia: perigynia ovate, 

 2.5 mm. long, pale, nerveless or very faintly few-nerved, each tipped with a 

 2-toothed beak about i the length of the body. M. Rather common, on dry 

 hillsides. Spr. and sum. 



5. C. sparganioides Muhl. Leaf -blades flat, 2.5-10 mm. wide, the lower very 

 short; sheaths white or pale: culms rough, 3-angled, 5-9 dm. tall: spikes 6-12, 

 oblong or subglobose, 5-8 mm. in diameter, the upper aggregated, the 2-4 lower 

 ones commonly separated: lower bracts developed: scales ovate, acute or cuspi- 

 date, at least as long as the body of the perigynia : perigynia flat, ovate, 3 mm. 

 long, spreading or radiating, pale, narrowly wing-margined, usually few-nerved 

 on the outer face, the rough 2-toothed beak the length of the body. Rather 

 rare, in woods and thickets. Sum. 



6. C. vulpinoidea Michx. Many leaves exceeding the culm; blades 2-5 mm. 

 wide: culms stiff, 3-angled, rough above, 3-12 dm. tall: bracts bristle-like, 

 numerous: spikes ovoid-oblong, 4-8 mm. long, very numerous in a cluster, 313 

 cm. long: scales lanceolate, acuminate or awned, about as long as the perigynia, 

 but narrower: perigynia ovate, 2-2.5 mm. long, greenish-yellow, flat, several- 

 nerved on the outer face, nerveless or faintly 1-3-nerved on the inner, each 

 tipped with a lanceolate 2-toothed beak about I as long as the body. Common, 

 in low meadows or swamps. Sum. 



7. C. prairea Dewey. Leaves light-green, mostly shorter than the culm; blades 

 plicate, 1-3 mm. wide: culms 3-10 dm. tall, very rough near the top: spikes 



