No. 20. 

 SPOROBOLUS WRIGHTII Munro in Herb. 



Plant perennial, coarse, with thickened bulbous base. 



Culms erect, not branching, terete, smooth and shining, 2 to 4 feet tall. 



Leaves; radical, few, scarious sheaths at maturity; of culm 4 or 5; sheaths 

 mostly exceeding internodes, closed, slightly hairy at the throat; blades flat or 

 involute, 2 or 3 lines wide, 1 to 2 feet long; ligule a minute fringe. 



Inflorescence a slender, erect, lanceolate panicle, 10 to 13 inches long; branches 

 mostly alternate, slender, erect-spreading, 1 to 4 inches long, bearing many shortly- 

 pedicellate spikelets on the outer two-thirds. 



Spikelets lanceolate, 1-flowered, 1 line long; first glume ovate, barely acute, 

 membranaceous, 1 -nerved, ^ to ^ line long; second glume same, but twice as large; 

 floral glume broadly lanceolate, acute, membranaceous, smooth, 1-nerved, f line 

 long; palet lanceolate, cleft at apex, slightly 2-keeled, § line long. 



Grain elliptical, compressed, brown, ^ line long. 



Plate XX; a, spikelet enlarged. 



A tall coarse grass, growing in dense tufts, commonly called Saccaton or Zac- 

 ate. Probably too coarse to be of agricultural value. 



Western Texas to southern California. 



