3<-ov^v^ Inmi A>o»t&^. No. 60. 

 TRISETUM BARBATUM Steud. Syn. PL Gram. 229 (1855). 



PZm?i perennial, few. culms in a stool, with fibrous roots. 



Culms erect, or decumbent at the base, often branched below, smooth, leafy nearly 

 to the panicle, 2 to 3 feet tall. 



Leaves of the culm 3 or 4; sheaths sparsely retrorsely hispid, half open above, 

 shorter than the interuodes; blades scabrid, sparsely hairy or nearly smooth, 2 to 3 

 lines wide, 3 to 6 inches long; ligule obtuse, erose, 1 line or less long. 



Inflorescence a loose, open, or often rather constricted, erect or fiexuous panicle 

 4 to 8 inches long; rays 2 to 5 at each of the 4 to 6 nodes, scabrid like the axis? 

 unequal, 3 inches long or less, spikelet-bearing toward the ends. 



Spikelets loosely 3- to C-flowered, 7 to 10 lines long; first empty glume very nar- 

 rowly ovate, subulate-acute, carinate, membranaceous and smooth, except the promi- 

 nent, slightly hispid keel, 3 to 4 lines long; second empty glume lance-ovate, acute, 

 often involute subulate, slightly hispid on the keel, 3-nerved, 5 to G lines long; floral 

 glume lanceolate, with two teeth, each about £ line long, at the apex, jmbesceiit 

 throughout, 5- to 7-nerved, 5 to 7 lines long; awn arising at the base of the sinus, 

 rather coarse, hispid and slightly twisted below, bent, £ to § inch long; palet linear, 

 thin, ciliate on the keels above, 4 to 5 lines long; grain spindle-shaped, reddish-brown, 

 subtranslucent, 3 to 4 lines long; internode of rachilla slender, about 1£ lines long. 



Plate LX; a, first empty glume; 6, second empty glume; c, floral glume, side 

 view; d, floral glume, dorsal view; e, palet, not opened; /, grain. 



Southern California. The description in Botany of California seems to include in 

 some characters the variety major Vasey, which differs from the type in having larger 

 spikelets and broader empty glumes moie or less plainly 3- and 5-nerved, respectively. 



Prof. Thurber, in Botany of California, is authority for the reference of this species 

 to T. barbatum Steudel, and only from description. The name does not occur in Four- 

 nier's Graminees Mexicaiues, and we have seen no authentic specimens of the species. 



