160 



HORDEAE 



I. CYPERUS L. 



Tufted or single stemmed, aimiuil or ijerennial grass-like herbs 

 15 inches high or less, with i)asiil leaves, triangular steins, and 

 flowers in head-like clusters (.r miKiually branched umbels subtend- 

 ed by one or more leaf-like Lracts; spikelets flattened or cylindric 

 glumes deciduous or if persistent the spikelets falling entire; glumes 

 2-ranked; flowers perfect; perianth none; stamens 1 to 3 ; achene 

 without a tubercle. 



PlanlH small. 2 to G inches high, annual; tips 

 of bracts subulate, conspicuously reflexed, 

 inflort'scence capitate. 

 Plants much taller than 6 inches, perennial 

 (rarely annual) ; tips of bracts mostly erect, 

 sometimes spreading. 

 Spikelets ovate to ovate-oblong, 4 to 5 mm. 

 long, crowded at tiie ends of the rather 

 long subequal rays of the umbel. 

 Spikelets linear to narrowly oblong. 



Spikelets narrowly oblong; scales of the 

 flowers not overlapping, especially in 

 fruit, very strongly nerved. 

 InHoiescence a compoiuid umbel with un- 

 equal rays. 



Inflorescence crowded, subcapitate. 

 Spikelets linear; .'^cales of the flowers over- 

 lapping fixini one-half to two-thirds 

 their length. 



Spilcelets deciduous as a wliole when ma- 

 ture. 



Spikelets with few, usually 2 or 3 

 flowers. 



Spikelets with 6 to 9 flowers. 

 Scales of spikelets falling away from the 

 rachllla. 



Uachilla narrowly winged, the wings 

 adiuUe, plants stout, stoloniferous; 

 spikelets loosely clustered. 

 Wings of the lachilla not adnata, form- 

 ing scales anterior to the flower. 

 Spikelets <lensely crowded; fiowers 

 nun.erous, about 20 to the spikelet; 

 scales of the flower not bordered 

 with led; plant stout. 

 S[)ikelets fewer, loosely clustered; 

 flowers 12 or le.ss: scales red-mar- 

 gined: i)lant slender. 



1. C. inflexus. 



C. cyrtolepsis. 



C. rusbyi. 



C. fendlerianus. 



C. uniflorus, 

 C. speciosus. 



C. esculentus. 



C. cri/thrurhizos. 

 C. Nphucclatus. 



I. CyperUS inflexus Muhl. in the mountains of the south- 

 er.) and southwestern part of the State; in the Upper Sonoran 

 /one. 



