CYPEEACEAE 



47 



III. 



Inflorescence usually IJ' or more long, the 

 clusters compouud. 

 Beak of the perigynium longer than the body. 

 Beak 1-2 times length of body. 

 Beak 3-4 times length of body. 

 Beak of perigynium shorter than the body. 

 Perigynium and beak V long. 

 Perigynium and beak \\" or less long. 

 Scales acute to acuminate. 

 Leaves exceeding stem. 

 Stem exceeding leaves. 

 Scales obtusish. 

 Inflorescence usually less than \\' long, the 

 clusters rather simple. 

 Clusters strongly separated. 

 Leaves Y'-W wide. 

 Perigynia radiating. 

 Perigynia reflexed at maturity. 

 Leaves 2J"-4J" wide. 

 Clusters aggregated. 



Heads green when mature. 

 Leaves 'if'-i" wide. 

 Leaves Y'-^" wide. 



Head 6" or less long, the clusters hardly 

 recognizable. 

 Leaves V'-'i" wide. 

 Leave V or less wide. 

 Head 6" or more long, the clusters rec- 

 ognizable. 

 Heads yellowish at maturity. 



IV. 

 Perigynia widely spreading. 

 Perigynia not widely spreading. 

 Perigynia 2-5 times as long as wide. 

 Spikes narrowly cylindrio, 6"-12" long. 

 Spikes globular to short-oblong. 

 Spikes cone-shaped above. 

 Spikes bluntish. 

 Perigynia erect. 

 Perigynia spreading. 

 Perigynia less than twice as long as wide. 

 Heads greenish-brown. 

 Perigynia ovate. 

 Perigynia orbicular. 

 Heads silvery-green. 



32. G. stipata. 



33. C Crus-Corvi. 



31. C. conjuncta. 



35. C. vulpinoidea. 



36. C. xanthocarpa. 



37. C. SartwelKi. 



38. C. rosea. 



39. C. retrnflexa. 



40. C. sparganoides. 



41. C. eephdloidea. 



42. G. cephalophora. 



43. C. LeavenwoHhii. 



44. C. Muhlenbergh. 

 34. G. gravida. 



45. C. sierilis. 



46. C. Muahingumensis. 



48. C. scoparia. 



47. ^C tribuloides. 



49. C. crisiatella. 



50. G. straminea. 



51. G. featucacea. 



52. 0. Bickneim. 



1. C. Aaa-Giayi Bailey. 2°-3° high : leaves many, Z"-\\" wide : 

 pistillate spikes 1-2, V in diameter, perfectly globular, 10-30-flowered : 

 perigynia much-inflated, many-nerved, 6"-10" long. — In low, wet woods 

 near Lake City and Sibley. Bare. May-June. 



2. C. lupulina Mnhl. 2°-4° high : leaves 2i"-4" wide : pistillate 

 spikes 2-6, oblong-cylindrical, V-2Y long, densely many-flowered, sessile 

 of short-stalked : perigynia e^'-Q" long, much inflated, many-nerved. — 



