. Family CYPERACEA 31 
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10. Carex. 189. 
Sedges. 
Achenes mostly triangular, never lenticular; stigmas three. 
Perigynia long-beaked, beak usually as long as the body. 
Perigynia gradually narrowed into the beak. 
Beak entire. 31. C. durifolia. 
Beak toothed. 
Teeth small, never wide spreading. 
Perigynia about 12 mm. long. 1. C. lupulina. 
Perigynia about § mm. long. 2. C. lurida. 
Teeth longer, often spreading. 
Seales long awned, awn longer than body of scale. 
Teeth short, not wide spreading. 3. C. hystricina. 
Teeth longer, wide spreading, mature perigynia re- 
flexed. 4. C. comosa. 
Seales awnless or short awned. 
Teeth not wide spreading; perigynia usually rough. 
6. C. trichocarpa. 
Teeth longer, wide spreading; perigynia smooth. 
7. C. atherodes. 
Perigynia abruptly narrowed into the beak. 
Scales about as long as the perigynium; spikes not globose. 
18. C. longirostris. 
Seales about half as long as the perigynium; spikes globose. 
5. C. squarrosa. 
Perigynia with short beaks, or beakless; beak much shorter than 
the body. 
Beaks of the perigynia with two teeth. 
Perigynia glabrous or nearly so. 
Teeth very small, scale long-awned. 17. C. davisii. 
Teeth larger, scale short-awned. 8. C. lacustris. 
Perigynia pubescent. 
Teeth evident, perigynia densely pubescent. 9. C. lanuginosa. 
Teeth minute, perigynia less pubescent. 
Staminate spike over 1 cm. long. 29. C. pennsylvanica. 
Staminate spike small, less than 1 cm. long. 30 C. varia. 
Beaks of perigynia entire or wanting (See No. 29 and 30 above.) 
Perigynia 4-5 mm. long. 
Pistillate spikes dense, many-flowered. 19. C. grisea. 
Pistillate spikes loose, with few scattered flowers. 
20. C. amphibola. 
Perigynia usually not over 3 mm. long. 
Spikes 2 or more, the upper staminate. 
Pistillate spikes drooping. 16. C. limosa. 
Pistillate spikes not drooping. 
Pistillate spikes dense flowered: 
Bracts with blades much longer than the subtended 
spikes. 
Bracts mostly overtopping the terminal staminate 
spike. 21. C. granularis. 
Bracts rarely overtopping the terminal staminate 
spike. 22. C. crawei. 
Bracts with shorter blades, rarely more than twice as 
long as the subtended spike. 
