146 GRAMINEAE. 
12. Muhlenbergia pungens Thurb. 
Prairie Muhlenbergia. (Fig. 331.) 
Muhlenbergia pungens Thurb. Proc. Acad. 
Phila. 1863: 78. 1863. 
Culms 6/-15’ tall from a creeping root- 
stock, erect from a decumbent branching 
base, rigid, minutely pubescent. Sheaths 
overlapping, crowded at the base of the 
culm, scabrous; ligule a ring of soft silky 
hairs; leaves 1/-2’ long, involute-setaceous, 
rigid, scabrous; panicle 3/-6’ in length, open, 
the branches 2/-214’ long, single, distant, 
much divided from near the base, the divi- 
sions apparently fascicled; spikelets on long 
pedicels, which are clavate-thickened at the 
apex; outer scales, when mature, equalling 
or often shorter than the body of the third 
one, scabrous, especially on the keel; third 
scale, when mature, 3’/-1’’ long, scab- 
rous, the awn shorter than its body. 
On prairies, Nebraska to Utah, south to Texas 
and Arizona, Aug.—Sept. 
26. BRACHYELYTRUM Beauv. Agrost. 39. 1812. 
A tall grass with flat leaves and a narrow panicle. Spikelets 1-flowered, narrow, the 
rachilla produced beyond the flower and sometimes bearing a minute scale at the summit. 
Scales 3; the outer small and inconspicuous, the lower often wanting; the third much 
longer, rigid, 5-nerved, acuminate into a long awn; palet scarcely shorter, rigid, sulcate on 
the back, 2-nerved Stamens 2. Styles short, distinct. Stigmas plumose, elongated. 
Grain oblong, free, enclosed in the scale and palet. [Greek, in allusion to the minute outer 
scales. ] 
A monotypic genus of eastern North America. 
1. Brachyelytrum eréctum (Schreb.) Beauv. Brachyelytrum. (Fig. 332.) 
Muhlenbergia erecta Schreb. Besch. Gras. 2: 139. pl. 
50. 1772-9. 
Brachyelytrum erectum Beauv. Agrost. 39. 1812. 
Brachyelyirum aristatum R. & S. Syst. 2: 413. 1817. 
Brachyelytrum aristatum var. Engelmanni A. Gray, 
Man, Ed. 5, 614. 1867. 
Culms 1°-3° tall, erect, slender, simple, smooth 
or rough, pubescent at and near the nodes. 
Sheaths shorter than the internodes, scabrous to- 
ward the apex, more or less villous especially at 
the throat; ligule about 3/’’ long, irregularly 
truncate; leaves 2/-5’ long, 3/’-9’’ wide, acuminate 
at both ends, scabrous; panicle 2-6’ in length, slen- 
der, branches 1/—3 long, erect or appressed; outer 
scales of the spikelet unequal, the upper less than 
one-third as long as the flowering scale, the lower 
minute or wanting; third scale, exclusive of the 
the awn, 4}2’’-6’ long, 5-nerved, scabrous, espec- 
ially on the midnerve, the awn erect, 9//—12/’ 
long; rachilla produced beyond the flower about 
half the length of the third scale and lying in the 
groove of the palet. 
Moist places, Newfoundland to western Ontario and Minnesota, south to North Carolina, Tenn- 
essee and Missouri. Ascends to 5000 ft. in North Carolina. July—Aug. 
