1018] The Grasses of Illinois 337 



d(L Central awn forming a loose spiral or strongly rcflexed and 

 hook-like; lemma 20 to 30 mm. long. A. ramossissivia 



h\\. Central awn differing slightly in length from the lateral ones, the latter 

 more or les^s horizontal ; glnmes almost equal in length, 

 c. Awns not over '6 em. long, glumes 9 to 12 mm. long. 



d. Leaf-blades smooth, not hairy; first glume longer than the 



second. A. purpurascens 



dd. Leaf-blades with long hairs near the base; first glume usually 



equal to, but sometimes longer than the second. A. stricta 



cc. Awns -1 to 7 cm. long; glumes 20 to 30 mm. long. A. oliganilui 



Aristida basiramea Eiigelm. 

 Forked Aristida. Tufted Triple-awn (Fig. 131) 



Gleason '10, 148. 



(Ailms branched, 8 to 24 inches tall; sheaths smooth, blades 1 to G 

 inches long, 1 to 2 mm. Avide ; panicles usually less than 6 inches long, 

 narrow, often partly included in the upper sheaths ; glumes pointed, 

 unequal, the first 8 to 12 mm., the second 12 to 14 mm. ; lemma about 

 10 mm. long, the middle awn 1 to 2 cm. long, the lateral awns 2 to 7 mm. 



This species is an annual growing in dry, sandy soil, and sandy 

 barrens. 



CHAMPAIGN CO. Urbana, Waite, Sept., 1888. JO daviess co. Without local- 

 ity, Pcpoon. HENDERSON CO. Oquawka, Pa-tterson 232; Oquawka, Traci/ in 1887. 

 ogle CO. Oregon, Waite, Sept., 1888. rock island co. Barstow, McDonald, 

 Aug., 1903 ; Osborn, Seymour, Sept., 1884. ST. clair co. Without locality, Bre7i- 

 del in 1850. 



Aristida desmantha Trin. and Eupr. 

 AVestern Aristida (Fig. 126) 



Culms branched, 1 to 2 feet tall ; sheaths loose, smooth ; blades 4 to 

 8 inches long, 1 to 2 mm. wide, roughened only on the upper surface; 

 panicle 4 to 8 inches long, a])out half as wide, the branches ascending ; 

 glumes shiny brown, about equal, 15 to 20 mm. long; lemma shorter, 

 the awns about equal, jointed to the lemma, reflexed and somewhat 

 coiled at base but not forming a spiral column. 



This species belongs to the southwestern part of the United States. 

 It is found in dry soil. 



ILLINOIS SPECIMENS: Without locality, Vasey. mason CO. Without local- 

 ity, M. S. Beib in 1861. 



Aristida dichotoma Michx. 



Poverty Grass (Fig. 128) 



Lapham '57, 545, 569 (Plate 2, Fig. 2); Patterson '76, 50; Flagg '78, 280; 

 Brendel '87, 88. 



Culms slender, much branched, usually branching at every node, 

 4 to 24 inches tall; sheaths loose, smooth; blades 1 to 3 inches long, 

 1 to 2 mm. wide, involute; panicles s])ike-like, 2 to 6 inches long; 

 glumes almost equal, 7 to 8 mm. lo"- - sharp-pointed ; lemma shorter, 



