■254 POACE.E. 



pubescent above and below, 4-6 cm. long, 1-1.5 mm. wide. Pan- 

 icle often included at the base by the upper sheath, slender, race- 

 mose, 8-15 cm. long, rays mostly solitary, erect or spreading, dis- 

 tinct, distant. Spikelets mostly subsessile and extending the whole 

 length of the branches, 2-3 mm. long; empty glumes ovate, 1- 

 nerved, subequal or the first sliorter, 0.5-0.8 mm. long; floral 

 glume 3-4 mm. long, scabrous, 3-nerved, linear-lanceolate, the slen- 

 der awn 3-3 cm. long; palea scabrous, lanceolate, little shorter than 

 its glume. Grain l.G mm. long. 



Arizona, Pr ingle; California, U. S. Dept. Ayr kid. 310 from 

 J^ones, Orcuttj Mexico, Palmer 510. 



Texas to California and Mexico. 



30. M. spiciformis Trin. Fund. Agrost. 2:42 (1841), Mem. 

 Acad. St. Petersb. (VI.) 6, 2: 285 (1845). 



A very slender, much-branched and diffuse annual, 30-60 cm. 

 high, sheaths smooth, half to three-fourths the length of the inter- 

 nodes; ligule 1 mm. long; blade thin, flat, 6-10 cm. long, 1.5-2 

 mm. wide. In some of the lower axils are siiort turgid sheath-like 

 bracts containing fertile flowers with hyaline glumes. Above are 

 filiform branches bearing each a single spike, 8-15 cm. long with 

 more or less distant spikelets which are single or branching once or 

 twice. Terminal panicles thin, linear, 10-15 cm. long, rays in 

 twos or single, the longest 2-3 cm. long, bearing short branches and 

 10-20 spikelets, subsessile or on pedicels 2-3 mm. long. Empty 

 glumes of these spikelets 1-nerved. the second less than 1 mm. long, 

 but longer than the first; floral glume thinly pilose on the lower 

 iialf of the central nerve and the margins, scarcely 3 mm. long, gra- 

 'duaUy tapering into an awn 1-2 cm. long; palea 2 mm. long, grain 

 nearly as long as the palea. Sessile spikelets borne on a bearded 

 pointed callus 2 mm. long in the axils of stiff lanceolate bracts 

 about their own length, first glume awl-shaped, 1-2 mm. long, sec- 

 ond linear-lanceolate, 6 mm. long, with a single double nerve; floral 

 glume as long as the second glume, 3-nerved; palea pilose, rachilla 

 constricted, 1-2 mm. long, bearing 3 awns 5-10 mm. long. 



Mexico, 



31. M. brevifolia Scribn, ined. 



