C'HL0R1DE.E. 413 



tana, Ihward, Canby c(- Scribucr 376; Texas, Drumniond 300, 

 Bolander; Mexico, Fendler 901. 



From Illinois to Texas, Kansas, Colorado, Montana, and Cali- 

 fornia. 



90. (181). BOUTELOUA Lag. Var. Cienc. 2: Part 4, 134 (1805). 

 Grama-grass. Musquit-grass. Atheropogoii Muhl. Willd. 

 8p. ri. 4:937 (1805). Hetcrosteca Dcsv. Nov. Bull. Soc. 

 Philom. 2:188 (1810). Triathera Desv. 1. c. Corethrum Vahl, 

 Skr. Naturk. Selsk. Kiobenh. 6:85 (1810). Clwndrosmm Desv. 

 Journ. Bot. 3:68 (1813). Dinebra DC. Cat. Hort. Mons. 104 

 (1813) in part. Trmna H. B. K. Nov. Gen. et Sp. 1 : 178 

 (1815.) PoJyodon 1. c. 174 (1815). Heterostega Kunth, Mem. 

 Mus. Par. 2:73 (1815). Actinuchloa Willd. E. & 8. Syst. 2:22, 

 417 (1817). Eutriana Trin. Fund. Agrost, 161 (1820). Aris- 

 tidium Endl. Gen. 94 (1836). Triplathem Endl. 1. c. Nestlera 

 Willd. Steud. Nom. Ed. 2, 2:192 (1841). 



Under each synonym above given may be found synonyms for 

 species. 



Spikelets 1-2 flowered, complanate, sessile and densely crowded 

 in 2 rows on one side of a flattened rachis, rachilla continuous or 

 articulate above the lower glumes, bearing 1-3 glumes or bristles or 

 rarely staminate flowers above the single perfect flower. Empty 

 glumes 2, narrow, acute, keeled, equal or unequal; floral glume 

 broader, usually firmer, 3-toothed or 3-cleft at the apex; empty 

 glumes at the apex of the rachilla 3-5-awned or deeply divided ; 

 palea of the perfect floret narrow, hyaline, entire or 2-toothed. 

 Stamens 3, usually orange-colored or red. Lodicules 2, fleshy. 

 Styles distinct. Grain oblong, included, but not adherent. Slen- 

 der annuals or perennials, low or tall, blades narrow, flat or convo- 

 lute. Spikes single and terminal, or several on the side of the axis, 

 first erect, finally drooping. 



There are about 25 species, all American. Bentham divided the 

 genus into 3 sections, founded mainly on the inflorescence. Plants 

 of this genus are most abundant in the warmer and dryer portions 

 of North America, esj)ecially in western Texas, in Arizona and 



