7 
CLXI, GRAMINEAE, 
6 3 \ aa é is 
Trize 1. STIPACEZ.—Infloresence panicled, Spikelets solitary, 1-flower- 
ed. Glumes membranaceous. Paleex mostly two, lower one coriaceous, 
involute, awned. 
1, ARISTIDA. 
Lat. arista, an awn; characteristic of the genus. 
Panicle contracted or racemose; glumes 2, unequal; palex pedi- 
cellate, lower one with 3 long awns at the tip, upper one very minute 
or obsolete. 
1. A. picHoTéma. Michx. Poverty Grass. 
Cespitose ; st. dichotomously branching; panicle contracted-racemose ; 
lateral awns very short, the intermediate one nearly as long as the palew, con- 
torted.—A slender grass, in sandy soils, U. S., common. Stems 8—12 high, 
branching at each joint. Leaves very narrow, with very short, open sheaths, 
and a very short stipule. Spikelets slender, on clavate peduncles. Aug. 
2. A. PURPURASCENS. Poir. 
St. erect, simple, filiform, 2—3f high; lws. very narrow, flat, erect, a foot 
in length, with short, open sheaths; panicle long, loosely spicate ; spikelets on 
short, clavate, appressed pedicels; awns nearly equal, divaricate, twice the 
length of the paler; palee often dark purple—. Sandy woods, Northern 
States. Sept. 
3. A. GRacitis. Ell. 
St. very slender, a foot or more high; lvs. setaceous, erect, with short 
sheaths, pilose at the throat; panicle very slender; spikeletssomewhat remote, ap- 
pressed ; lateral awns short, erect, intermediate one longer, spreading. - -2| Mass. 
and S. States. A grass of little value, as well as the other species of this genus. 
4. A. TuBERcULOsA. Nutt. Long-awned Poverty Grass. 
St. erect (declinate at base), 8—20/ high, rigid, with small tubercles in the 
axils of the numerous branches; nodes tumid; ls. long and narrow-linear ; 
panicle large, loose, simple ; spikelets pedicellate; glumes nearly 1’ long, linear, 
awned ; upper palee involute, the awns 2’ long, hispid upwards, twisted together 
to near the middle, thence finally horizontally divaricate—2 A very singular 
species, in dry prairies, Hl., Mead! July, Aug. 
