No, 32, 



TRIODI A ACUMINATA (Munro.) Vasey. (Tricuspis acuminata Munro in 



Herb.) 



Plant annual or short-lived perennial, tufted with rather bulbous base. 



Culms erect, slender, not branching, slightly compressed, smooth or sparsely 

 pubescent, 6 to 12 inches tall. 



Leaves ; radical, numerous, with short, tapering, compressed sheaths, and 

 flat or folded, abruptly pointed, pubescent blades, 2 to 3 inches long ; of culms 2 

 or 3 ; sheaths mostly shorter than internodes, close, nearly smooth ; blades like 

 those of radical leaves but shorter ; ligule a minute, bristle-like fringe. 



Ipflorescence a contracted, close head or panicle, 1 to 2 inches long, light colored 

 or often purplish, composed of 7 to 15 nearly sessile, densely flowered spikelets 

 or branches, \ to f inch long, sometimes interrupted below. 



Spikelets lanceolate, compressed, 9- to 12-flowered, 2 to 3 lines wide, 5 to 7 lines 

 long ; internode of pubescent rachilla less than \ line long ; first glume ovate, 

 acuminate, or awl-pointed, carinate, scarious, smooth, 1 -nerved, 2 to %\ lines long ; 

 second glume same but nearly + line longer ; floral glumes ovate, acuminate, 

 slightly obtuse or somewhat 2- toothed at apex, carinate, membranceous, pubescent 

 on the 3 nerves at base, 2 to 2-J lines long, 2 lateral nerves marginal, midnerve ex- 

 current in a short slender awn : palet lanceolate, finely pubescent on the two prom- 

 inent keels and at base, 1 to 1-| lines long. 



Grain irregularly spindle shaped, light-green, \ line long. 



Pla^e XXXII ; a, spikelet ; b, empty glumes ; c, floral glume ; d, palet. 

 Texas to Arizona, and Mexico. 



