48 CYPERACEAE 



Low wet woods from Sibley to Atherton. Locally abundant. May- 

 September. 



3. C. monile Tuckerm. Culms 2°-3° high: leaves W'-2\" wide: 

 staniinate spikes 2-4 : pistillate 1-3, V-2' long, narrowly cylindric, 

 many-flowered : perigynia somewhat inflated, 2V' long, strongly-nerved. 

 Abundant near Lake City and Sibley. May-June. 



4. C. lurida Wahl. l2°-3° high: leaves long and rough: pistillate 

 spikes 2-4, densely flowered, erect, spreading or drooping, sessile or short- 

 stalked, 9'^-24^^ long : perigynia 10-nerved, inflated, slender-beaked, A" 

 long, the teeth V-2'' long : staminate spike solitary. — Verj- common in 

 bogs along the bluffs west of Sibley. June-July. 



Var. exundans Bailey. Pistillate spikes all long-stalked. — Occasionally 

 occurs with the type. 



5. C. hystricina Muhl. Like the last, but pistillate spikes shorter 

 {Y-\Y long), the lower slender-stalked and drooping : perigynia l"-^" 

 long, little-inflated, 15-20-nerved, the beak strongly toothed.— With the 

 last, but matures from May-June before C. lurida is noticeable. 



6. C. Frankii Kunth. l°-2° high, with long rough leaves and similar 

 bracts, much longer than the culm : pistillate spikes 3-5, very dense, 

 V-\Y long. 4'^ in diameter : perigynia abruptly contracted and depressed 

 at the summit, from the center of which depression arises the slender beak. 

 —Common in wet grounds throughout. June-September. 



7. C. typhinoides Schwein. 2°-3° high: leaves 2'^-3'^ wide : spikes 

 1-3, oblong, densely flowered, Y-W long, 6^^ in diameter, the terminal 

 staminate at base; perigynia obovoid, widely spreading or ascending, 

 beaked, twice the length of the inconspicuous scale. Bogs west of Sibley. 

 Not common. May-June. 



8. C. trichocarpa Muhl. l°-4° high, stout : leaves and bract exceed- 

 ing the culms: staminate spikes 2-6: pistillate spikes 2-5, cylindric, 

 l/_4/ long: perigynia long-conic, 4''^-5'^ long, many-nerved, tapering 

 into a stout 2- toothed beak, smooth : scale hyaline, shorter than perigynia. 

 Our form is var. imherhis Gray. — Low swales in the Missouri River bot- 

 toms. Not common. May-June. 



9. C. aristata li. Br. Resembles the last, but sheaths pubescent : spikes 

 sometimes 5' long: perigynia slender: scales terminating in an awn of 

 their own length.— Abundant around Fish Lake near Sibley. May-June. 



10. C. riparia Curtis. Culms 2''-4° high : leaves rough, long and 

 broad : staminate spikes several : pistillate spikes 2-4, U'-4Mong, usually 

 erect, loosely flowered below : perigynia ovate-lanceolate, not inflated, 

 few-nerved, coriaceous : scale exceeded by perigynia.— Low swales and 

 swamps, especially along the Missouri River. Common. May-June. 



11. C. lanuginosa Michx. Culms 2°-3° high, rough above : leaves 

 l//-2^^ wide : staminate spikes 1-3 : pistillate spikes 2-3, rather distant, 

 1^-2^ long, densely flowered : perigynia hairy, ribbed, V^ in diameter, 



