28 



Spikelets short-pedicellate, narrowly ovate, acute, 2 or rarely 3 mm. long; first 

 glume acute or acuminate, 3-nerved, one-half as long as the spikelet; second 

 glume broadly ovate, acute or apiculate, 5-nerved, nearly equaling the spikelet 

 in length; third glume similar to the second, 5-nerved, equaling the flowering 

 glume, subtending a lanceolate, hyaline palea; glumes pale, with prominent 

 green nerves; flowering glume narrowly ovate, acute, short-apiculate, striate, 

 nearly smooth, obscurely transversely wrinkled below, the inclosed palea simi- 

 lar in texture and markings, convex. 

 Colorado to Arizona, Texas, Mexico, and South America. June-October. 



Specimens examined. — Colo- 

 rado: Canyon City, 780 

 Jones 1878, 4 Eastwood 

 1892, 979 Shear 1896. 

 Arizona: No locality, 

 Palmer 1869, Vasey 1889, 

 19, 21 Emersley 1890; 

 Bisbee, 858, 926 Mearns 

 1892; Tucson, Pringle 

 1884, 805 Tourney 1892, 77 

 Tourney 1894; Gila Val- 

 ley, 334 Rothrock 1874; 

 Fort Verde, 939 McDougal 

 1891;,, Fort Huachuca, 

 Wilcox 1894. New Mexico: 

 No locality, 2094 Wright 

 1851-52; Mesilla, 60Woo- 

 ton 1897; Rincon, 41, 44(f, 

 63 Jones 1884; Albuquer- 

 que, 85 Tracy 1887; Las 

 Cruces, Vasey 1881; Man- 

 gos, Metcalfe 1897, Smith 

 1896. re.ra&- No locality, 

 Nealley 1877; Western 

 Texas, 799 Wright 1849; 

 Maraniflas, Havard 1883; 

 Mesquite Bay , Ravenel 

 1869; Pinto Creek, Kin- 

 ney Co., 83 Hall 1895; 

 San Diego, Smith 1897; 

 Painted Cave, Val Verde 

 Co., 115 (in part) Nealley 

 1892. Mexico: Guaymas, 

 340 Palmer 1887; San 

 Bernardino ranch, Mexi- 

 can boundary, 746, 771, 

 781 Mearns 1892; San Luis Mountains, 2101 Mearns 1893; White Water, 2313 

 Mearns 1893. 

 This common southwestern grass has been variously referred by American authoi-s 

 and collectors to Setarla caudata and Setaria setosa, but is at once distinguished 

 from these species by its pale aspect, cylindrical panicle, long glaucous leaves, 

 and long first and third glumes. Setaria caudata in Bui. No. 12, Div. Bot. U. S. 

 Dept. Agr., "Grasses of the Southwest," pi. 5 (1891), and in "Bot. of Western 

 Texas," Contr. U. S. Nat. Herb. 2: 510 (1894), Chumiemphis caudata in Beal 

 Grasses of N.Am. 2:157 (1896). 



Fig. 15. — Ghcetochloa coinposita: spikelet showing seta, two views 

 of the spikelet, anil dorsal view of theflowering glume. 



