No. 49. 

 ERAGROSTIS PURSHII Shrad. 



Plant annual, diffuse, spreading fi'om a tufted base. 



Roofs sometimes secondary from lower nodes, seldom branched. 



Culms ascending, often prominently geniculate, slightly compressed, and 

 grooved or flattened above each sheath, smooth, often branching below, 15 to 20 

 inches tall. 



Leaves of sterile culms rather numerous, with flat or slightly involute blades 

 3 to G inches long; of stem 3 or 4; sheath 1 to 2 lines wide, 4 to 7 inches long; 

 ligule a spreading tuft of fine white hairs 1^ lines long. 



Inflorescence a rather loose, oblong panicle, 5 to 7 inches long; rachis angular, 

 somewhat flexiious, branches 1, 2, or 3 in a place, 2 to 4 inches long, with few or no 

 hairs at the axis, bearing 12 to 20 aj)pressed sjjikelets on angular, twisted, hispid 

 pedicels of varying lengths. 



Spikelets linear-lanceolate, 5- to 10-flowered, 2 to 3i lines long; intornodcs of 

 slender rachilla J line long; first glume ovate, acute, minutely hispid on back 

 above, 1-nerved, ^ line loiig; second glume same as first but nearly twice as large; 

 floral glumes broadly ovate, acutish, convex, scarious, 3-nerved, f to nearly 1 line 

 long; palet linear-oblong, minutely i^ubescent on the 2 nerves, | line long, arched, 

 remaining on the rachilla after the seed falls with the floral glume. 



Grain amber colored, ol)l»ng, ^ line long. 



Plate XLIX; a, spikelet with pedicel; h, empty glumes; h', end h", apexes 

 of empty glumes; c, floral glume, dorsal and side view; d, jsalet. 



Texas to Arizona and Mexico. In the Northern States this species seems to 

 be confused with Eruyrosfis jjilosa. 



