54 



Avery well markefl species, characterized by rigid basal leaves and densely flowered 

 dark-purple panicles, and especially by its rigid glumes and naked flowering 

 glumes. Distributed as Poa iinUuteraJis, with wliich it has no resemblance 

 excepting in its densely flowered panicle. 



POA LONGEPEDUNCULATA Scribn., sp. u. (PI. XI.) 



A slender, erect, and rather densely ca^spitoso grass, ."> to 7 dm. high, from short, 

 creeping rootstocks, with narrow basal leaves and long-exserted and densely 

 flowered panicles, 5 to 7 cm. long. Culms smooth, excepting just below the 

 panicle where they are minutely scabrous as is the main axis of the panicle. 

 Sheaths loose and crowded at the ba.se, minutely scabrous. Ligule about 1 mm. 



in length. Leaf-blades of the sterile 

 shoots .5 to 20 cm. long ; those of the 

 culm, two or three, the uppermost 

 rarely exceeding 1 cm. in length, 

 sometimes reduced to a unicronate 

 point, lowermost rarely more than 

 1 cm. long, 1 to 2 mm. wide, 

 minutely scabrous above and be- 

 low, conspicuonsly roughened near 

 the rigid apex. Panicle branches 

 1 to 2 cm. long, the shorter ones 

 flower-bearing to the base. Pedi- 

 cels scabrous. 8pikelets narrowly 

 oljlong-lanceolale, somewjiat com- 

 pressed, usually about (i mm. long, 

 3- to 5-flowered. Outer glumes 

 minutely scabrous on the keels, the 

 first 2-nerved, the broader second 

 glume 3-nerved, with broadly sub- 

 hyaline margins. Flowcringglumes 

 about 1 mm. long, minutely rough- 

 ened on the keel, especially near 

 the apex and finely pubescent on 

 the dorsal and marginal nerves near 

 the base. Intermediate nerves in- 

 distinct. Palea shorter than the 

 flowering glume, scabrous on the 

 nerves, and very minutely pubes- 

 cent between them, the apex hya- 

 line, adherent to the grain. 

 Loose, gravelly soil, summit of Sheep 

 Mountain, Laramie, Albany County, 

 "\Vyo., altitude 2,700 meters (Aveu 

 Nelson,, July 3, 1897). Rather scarce. 



AGROPYRON ELMERI Seiibn., 

 sp. n. (I'l. XIL ) 



A stout, erect ])erennial, !• to l."> tlm. 

 high, from st rong creeping rootstocks, with rather narrow, flat, erect, or ascend- 

 ing leaves and spikes 1.") to 20 cm. huig. Culms smooth. She.aths smooth, lower 

 ones longer than the internodes. Ligule about 1 mm. long, minutely fringed 

 along tlie edge, anricled. Lower leaves 20 cm. long, the upper (mes shorter, 

 4 to 6 111111. broad, stiigose-scabrous above, smooth beneath, long attenuate- 

 pointtsd; leaves of the innovations longer and narrower. .\xis of the spike not 

 readily breaking uj). S])ikelet8 approximate but. not crowded, comjiressed, 



-I'oa caj/illaris Scribii. 



h. flon'l. 



spikelet; 



