48 CYPERACEAE 



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

 September. 



3. C. monile Tuckerm. Culms 2-3 high : leaves \\ ff -^\^ wide : 

 staminate spikes 2-4 : pistillate 1-3, l'-2' long, narrowly cylindric, 

 many-flowered : perigynia somewhat inflated, 2i x/ long, strongly- nerved. 

 Abundant near Lake City and Sibley. May- June. 



4. C. lurida Wahl. lJ-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, 4" 

 long, the teeth l x/ -2 /x long : staminate spike solitary. Very 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 

 ('-!' long), the lower slender-stalked and drooping : perigynia %"-2" 

 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, 

 i'-lj' 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 /x -3 x/ wide : spikes 

 1-3, oblong, densely flowered, f'-ll' 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. imberbis Gray. Low swales in the Missouri River bot- 

 toms. Not common. May-June. 



9. C. aristata R. 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, l2 / -4 / long, 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// w ide : staminate spikes 1-3 : pistillate spikes 2-3, rather distant, 

 l / -2 / long, densely flowered : perigynia hairy, ribbed, 1 // in diameter. 



