398 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



plentiful, sheep are removed from it on account of the injury inflicted by the sharp- 

 pointed spikes which work into their feet and disable them. When young, especially 

 before blooming, it is readily grazed by stock, but even then the plants too easily pull 

 up by the roots, the feed therefore being mixed with sand to an annoying extent. In late 

 autumn, after the spikes have fallen off, the grass apparently affords but little nutri- 

 ment and stock avoid it as much as possible. Associated with it in this country is 

 usually found Aristida humboldtiana, which has similar characteristics and which 

 adds to the injurious effects. 



HERBARIUM SPECIMENS. 



Arizona: Mearns 1122, San Pedro River near Mexican Boundary; 924, south of Bisbee. 

 Rothrock 701, Riley's W T ell (near Tucson). Smart 429,. Camp McDowell. 

 Rusby 891, Beaver Creek. Tourney 802 and in Seymour's Grasses 84, Tucson. 

 Griffiths 1523, 3343, Tucson; 1922, Cochise; 1818, Mescal; 1928, Pearce; 3379 and 

 3418, Santa Rita Forest Reserve. Jones 6065, Canaan Ranch. Wilcox, Fort 

 Huachuca. Blumer 1705, Paradise. Hitchcock 3490, 3507, 3510, Tucson; 3665, 

 Patagonia. 



California: Orcutt, San Diego. 



New Mexico: Mulford 1000, Florida Mountains. Metcalfe 702, Silver City. CocJce- 

 rell 18, Jarilla Junction. Plank 43, Socorro. Wooton 1053, Las Cruces; 411, 

 Donna Ana County. Mearns 2340, Dog Mountains; 924, south of Bisbee. Hitch- 

 cock 3756, Deming. 



Texas: Cockerell 14, Fort Bliss. Plank 8, Llano; 63, El Paso. Nealley, Laredo. 



Mexico: Palmer 1353, 1354, Soledad, Chihuahua; 162, Guaymas; 1650, Lodiego; 1547, 

 Culiacan; 7, Yaqui River; 177 and 714a, Durango; 859, Carmen Island; 697, 

 Alamos. Pittier 474, Tlahualilo, Durango. Brandegee, Culiacan; 4, San Jose del 

 Cabo, Lower California. Schaffner, San Luis Potosi. Pringle 477, Chihuahua; 

 4592, Tequila. Parry & Palmer 941, San Luis Potosi. Hitchcock 3638, Nogales; 

 3594 and 3533, Hermosillo; 3549, Guaymas; 3527 and 3519, Llano. Rose 2490, 

 San Juan Capistrano. Nelson 6329, Casas Grandes, Chihuahua. 



South America: Stuckert 10624, 12791, 13764, and 20114, Argentina; Kneucker Gram. 

 Exsic. 448; Kurtz Herb. Argent. 12670. 



20. Bouteloua pringlei Scribn. 



Bouteloua pringlei Scribn. U. S. Dept. Agr. Div. Agrost. Circ. 30 : 4. 1901. Type, 

 Pringle 8374, collected in the mountains above Iguala, Guerrero, Mexico, October 24, 

 1900, in the National Herbarium. 



description. 



An erect, cespitose perennial, a meter high, resembling B. curtipendula in general 

 appearance and habit; culms erect, simple; nodes and internodes smooth, but sheaths 

 densely papillose-hairy upward, nearly smooth below, rather loose, with a small, 

 densely hairy ligular region; blades long, flat, 5 to 7 mm. wide, more sparingly papil- 

 lose-hairy; inflorescence racemose, the lower spikes showing a slight tendency to 

 become compound, about 30 cm. long, the spikes arranged bilaterally but so curved 

 or twisted, especially above, as to appear unilateral; spikes variable in size, small 

 above and passing gradually into larger ones below, and finally by indistinct grada- 

 tions into spike-bearing branches in the lower portion of the incipient panicle; spike- 

 lets 4 to 5 mm. long, not pectinate, consisting of a single floret and a rudiment repre- 

 sented by a very short prolongation of the rachilla; first glume nearly 3 mm.. long, 

 with hispid keel, the second densely hairy, nearly 4 mm. long, lanceolate, acuminate; 

 lemma ovate, long ciliate hairy on the edges and terminating in three short, equal, 

 hispid awns, about 4 mm. long; palet oblong, terminating in two short, hispid awns; 

 rudiment very short, often difficult to distinguish; caryopsis oblong, 2 mm. long, 0.3 



