WOOTON AND STANDLEY FLORA OF NEW MEXICO. 107 



the central spikelet into a naked bristle; glumes 2, narrowly lanceolate, subulate, 

 or setaceous, rigid, persistent; lemmas lanceolate, rounded on the back, obscurely 

 5-nerved above, usually awned; palea shorter than the lemma, 2-keeled; stamens 3; 

 Btyles very short, distinct; grain sulcate, adherent to the palea. 



KEY TO THE SPECIES. 



Plants glaucous throughout 1. H. murinum. 



Plants not glaucous. 



Glumes 3 to 6 cm. long 2. H. jubatum. 



Glumes 1 to 2 cm. long. 



Awns spreading; spikes yellowish 3. H. caespitosum. 



Awns erect; spikes reddish or brownish green 4. H. nodosum. 



1. Hordeum murinum L. Sp. PI. 85. 1753. Wall barley. 

 Type locality: "Habitat in Europae locis ruderatis." 



Range: Native of Europe, widely naturalized in the United States. 

 New Mexico: Mangas Springs; Mesilla Valley. 



2. Hordeum. jubatum. L. Sp. PI. 85. 1753. Squirrel-tail grass. 

 Type locality: "Habitat in Canada." 



Range: Alaska and British America to California, New Mexico, and Missouri. 



New Mexico: Farmington; Carrizo Mountains; Tunitcha Mountains; Chama; 

 Raton; Sierra Grande; Magdalena Mountains; Pecos; Torrance; Rio Pueblo; Mora; 

 Pescado Spring; Santa Fe; Kingston; White Mountains. Plains and meadows, in 

 the Upper Sonoran and Transition zones. 



Often a troublesome weed in cultivated ground. 



3. Hordeum caespitosum Scribn. in Pammel, Proc. Davenport Acad. 7: 245. 1899. 

 Type locality: Edgemont, South Dakota. 



Range : Wyoming and South Dakota to northern New Mexico. 

 New Mexico: Farmington {Standley 6904). Dry hills and plains, in the Upper 

 Sonoran Zone. 



4. Hordeum nodosum L. Sp. PI. ed. 2. 126. 1762. Meadow barley. 

 Type locality: "Habitat in Italia, Anglia." 



Range: Temperate North America, Asia, and Europe. 



New Mexico: Tunitcha Mountains; Chama; Ramah; Grants Station; El Rito 

 Creek; Rio Pueblo. Wet ground, in the Transition Zone. 



73. SIT ANION Raf. 



Cespitose perennials with mostly flat leaves and terminal bearded spikes; spike- 

 lets usually 2, sometimes 3 or 1, at each joint of the rachis, 2 to several-flowered; 

 glumes many-parted from near the base or merely bifid, or subulate and entire, awned; 

 lemmas terminating in a single long awn, or trifid and 3 awned; palea as long as the 

 lemma, entire, bidentate, or 2-awned. 



KEY to the species. 



Glumes bifid from about the middle, the lobes abruptly divergent. 



Sheaths long- villous 1. S. molle. 



Sheaths not villous. 



Glumes 3 to 4 cm. long 2.' S. caespitosum. 



Glumes 2 to 3 cm. long 3. S. rigidum. 



Glumes entire, subulate-setaceous. 



Culm leaves long and flexuous 4. S. longifoKum. 



Culm leaves short, rigid, spreading. 



Lemmas 10 mm. long, glaucous 5. S. hrevifolium. 



Lemmas 7 mm. long, soft-pubescent 6. S. pubiflorum. 



