MONOECIA.— TRIANDRIA. 33S 



* * Spikes several, aggregated into a head. 



7. C. cephalophora : spikes collected into an elliptical 

 head ; fruit ovate, scabrous on the margin above ; 

 about equal to the ovate subaristate glume. 

 IIAB. Hills. May. H. Culm 1—2 ft. high, ces< 

 pit., wiry; head subtri fid. 



* * * Spikes distinct, (not aggregated into a head.) 



a. Summit staminiferous. 



1. With 2 stiginas. 



3. C. bromoides : spikes 4 — 6, alternate, oblong, erect, 

 uppermost one sterile above, the rest pistilliferous 

 or androgynous (sterile above and below ;) fruit 

 erect, lanceolate acuminate, scabrous, nerved, bi- 

 fid, longer than the ovate-lanceolate glume. 

 HAB. Bogs. May. 1*. Culm 12—18 in. high, 

 slend. ; spik. sitbdist., h in* long. 



9. C. retrojlexa : spikes about 4, subapproximate, 



ovate, the lowest one with a short bract ; fruit 

 ovate-lanceolate, bidentate, scabrous on the mar- 

 gin, spreading and reflexed, as long as the ovate 

 acute glume. 

 HAB. Meadows, &c. May. U. Culm 8—12 in. 

 high, subhexang. ; spik. 3 — 4 — 5. 



10. C. rosea: spikes 4 — 6, remote, about 9-flowered ; 

 the lowest one with a setaceous bract overtopping 

 the culm ; fruit ovate, acuminate, diverging and 

 radiate, scabrous on the distinct margin, twice as 

 long as the ovate obtuse glume. 



IIAB. Moist woods, &c. May. H . Culm 12 in. 

 high ; spikes 1 in. distant, yell.-gr. 



11. C. disperma : spikes about 3, rather remote, 

 mostly 2-flowered, somewhat erect, the lowest 

 one bracteate ; fruit ovate, rather obtuse, nerved, 

 plano-convex, smooth, with a scabrous margin, en- 

 tire at the point, twice as long as the ovate, obtuse 

 submucronate glume. 



IIAB. iMountain woods. May — June. U . Culm 

 6 — 12 in. high ; fruit small. 

 12. C. Muhlenbergii : spikes about 5, ovate, crowded 

 at the summit of the culm, bracteate at the base •• 



