GRAAflNEAE. IOI 



cm. long or less, ascending or erect; outer scales of the spike let unequal, obtuse or 

 rounded at apex, about one-third the length of the third scale, which is 2.5-3 mm - 

 long, exclusive of the awn, and strongly scabrous; awn 1.2-2.4 cm - in length. In 

 dry soil, Kans. to Cal., south to Mex. 



11. Muhlenbergia capillaris (Lara.) Trin. LONG-AWNED HAIR-GRASS. 

 (I. F. f. 329.) Culms 4.5-12 dm. tall, erect, simple, smooth or nearly so. Sheaths 

 smooth, the lower short and overlapping, the upper ones much longer; leaves 1.5-3 

 dm. long, 2-4 mm. wide, scabrous; panicle 1.75-3 dm. in length or more, diffuse, 

 the capillary branches 1-2 dm. long, at length widely spreading; spikelets on long 

 hair-like pedicels which are clavate -thickened at the apex; outer scales unequal, 

 acute or short-awued, slightly scabrous; third scale, exclusive of the awn, 4 

 mm. long, about twice as long as the first one, scabrous, the awn 6-18 mm. in 

 length. In dry sandy or rocky soil, Mass, to N. J. and Mo., south to Fla. and 

 Tex. Panicle usually light purple. Sept. -Oct. 



12. Muhlenbergia gracillima Torn FILIFORM MUHLENBERGIA. (I. F. f. 

 330.) Culms 1-3.5 dm. tall, from a slender creeping rootstock, erect, slender, sim- 

 ple, rigid. Leaves 2.5-5 cm * ^ on S> involute-setaceous, smooth or somewhat sca- 

 brous, rigid, the basal numerous, usually strongly recurved, the 1-3 culm leaves 

 erect or ascending; panicle 5-22.5 cm. in length, open, the branches finally widely 

 spreading, 2.5-7.5 cm. long, filiform; spikelets about as long as the filiform pedi- 

 cels, which are clavate-thickened at the apex ; outer scales unequal, usually awn- 

 pointed or short-awned, slightly scabrous; third scale 2.5-3 mm - l n g> longer than 

 the outer ones, sometimes twice as long, scabrous ; awn 2-4 mm. long. On prairies, 

 Kans. to Colo., south to Tex. and N. Mex. Sept.-Oct. 



13. Muhlenbergia pungens Thurb. PRAIRIE MUHLENBERGIA. (I. F. f. 

 331.) Culms i-5~3-75 dm. tall, from a creeping rootstock, erect from a decumbent 

 branching base, rigid, minutely pubescent. Sheaths crowded at the base of the 

 culm, scabrous; leaves 2.5-5 cm - l n g> involute-setaceous, rigid, scabrous; panicle 

 7.5-15 cm. in length, open, the branches 5-6.25 cm. long, single, distant, much di- 

 vided from near the base, the divisions apparently fascicled; spikelets on long ped- 

 icels, 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, 1.5-2 mm. long, scabrous, the awn shorter than its body. 

 On prairies, Neb. to Utah, south to Tex. and Ariz. Aug. -Sept. 



32. BRACHYELYTRUM Beauv. 



A tall grass with flat leaves and a narrow panicle. Spikelets I -flowered, nar- 

 row, 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 want- 

 ing; 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 east- 

 ern N. Am. 



I. Brachyelytrum erectum (Schreb.) Beauv. BRACHYELYTRUM. (I. F. f. 332.) 

 Culms 39 dm. tall, pubescent at and near the nodes. Sheaths more or less villous, 

 especially at the throat; leaves 5-12.5 cm. long, 6-18 mm. wide, scabrous; panicle 

 5-15 cm. in length, slender, branches 2.5-7.5 cm. long, erect or appressed; outer 

 scales of the spikelet unequal, the upper less than one-third as long as the flower- 

 ing scale, the lower minute or wanting; third scale, exclusive of the awn, 9-12 mm. 

 long, scabrous, especially on the midnerve, the awn erect, 1.8-2.4 cm. long. Moist 

 places, Newf. to western Ont. and Minn., south to N. Car., Tenn. and Kans. 

 July-Aug. 



33. HELEOCHLOA Host. 



Perennial tufted grasses with flat leaves and spicate or paniculate inflorescence. 

 Spikelets i-flowered. Scales 3 ; the 2 outer empty, somewhat unequal, membran- 

 ous, acute, ciliate-keeled ; the third scale similar, a little longer ; palet shorter, 

 hyaline, 2-nerved. Stamens 3. Styles distinct. Stigmas plumose. Grain 

 oblong, free, loosely enclosed in the scale. [Greek, signifying meadow-gras>.j 



