MANUAL OF THE GRASSES OF THE UNITED STATES 261 



open woods, and rocky slopes, South Dakota to British Columbia, 



Fioure 513.— Sitanion jubatum. Pair of spiklets, X 2. (Type.) 



south to Missouri, 



Fioure 514.— Distribution of 

 Sitanion jubatum. 



and S. montanum J 



Texas, California, and Mexico (fig. 516). At high 

 altitudes plants often dwarf. Softly pubes- 

 cent plants have been differentiated as S. 

 cinereum J. G. Smith (the pubescence whitish) 

 and S. velutinum Piper; short-awned plants 

 as S. insulare J. G. Smith and S. marginatum 

 Scribn. and Merr.; rather small plants with 

 unusually slender awns as S. minus J. G. Smith, 

 and tall plants with coarse spikes as S. brevi- 

 folium J. G. Smith, S. longifolium J. G. Smith, 

 G. Smith. 



45. HYSTRIX Moench 



Spikelets 2- to 4-flowered, 1 to 4 at each node of a continuous flat- 

 tened rachis, horizontally spreading or ascending at maturity ; glumes 

 reduced to short or minute awns, the first usually obsolete, both often 

 wanting in the upper spikelets; lemmas convex, rigid, tapering into 

 long awns, 5-nerved, the nerves obscure except toward the tip; palea 



