100 FLORA. 



glabrous. Leaves 5-12.5 cm. long, 2-6 mm. wide, scabrous; panicle 5-11.25 cm. 

 in length, usually dense and interrupted, the branches 1.25-2.5 cm. long, erect or 

 appressed, the spikelets much crowded; outer scales of the spikelet acuminate, 4-6 

 mm. long, including the awn, smooth, or scabrous, especially on the keel; third 

 scale one-half to two-thirds as long, acuminate, the strongly scabrous midrib 

 excurrent in a short point. In wet places, Newf. to Br. Col., south to N. J., Mo. 

 and N. Mex. Aug. -Sept. (M. gtonu-rata Trin.) 



4. Muhlenbergia sylvatica Torr. WOOD MUHLENBERGIA. (I. F. f. 323.) 

 Culms 3-9 dm. tall, erect, branched. Leaves 5-17.5 cm. long, 2-6 mm. wide, 

 rough; panicle 7.5-17.5 cm. in length, somewhat lax, the branches 2.5-7.5 cm. 

 long, erect or ascending; outer scales of the spikelet 2. 5-3 mm. long, awn-pointed, 

 scabrous ; third scale equalling or somewhat exceeding the outer ones, strongly 

 scabrous, attenuate into a slender awn 2-4 times its length. In moist woods and 

 along streams, N. B. to Ont. and Minn., south to N. Car., Tenn., Neb. and thelnd. 

 Terr. Aug. -Sept. 



5. Muhlenbergia ambigua Torr. MINNESOTA MUHLENBERGIA. (I. F. f. 

 324.) Glabrous; culms 3 dm. tall or lower, erect, branched, smooth. Sheaths 

 shorter than the internodes; leaves 2.5-7.5 cm. long, 2-4 mm. wide, scabrous; 

 panicle 2.5-7.5 cm. long, rigid, its branches 1.25-2.5 cm. long, dense, appressed; 

 outer scales of the spikelet awn-pointed, unequal, the longer about 4 mm. in length 

 and exceeding the body of the third scale, which is scabrous, villous, and attenuate 

 into an awn 23 times its length; a fourth narrow awned scale is nearly always 

 present. Along a lake shore in Minn. 



6. Muhlenbergia comata (Thurb.) Benth. HAIRY MUHLENBERGIA. (I. F. f. 

 325.) Culms 3-7.5 dm. tall, erect, slender, smooth and glabrous. Sheaths shorter 

 than the internodes, smooth or slightly scabrous; leaves 6.2-12.5 cm. long, 2-4 mm. 

 wide, erect, flat, rough; panicle often tinged with purple, 5-10 cm. in length, dense, 

 branches 1.25-3.75 cm. long, erect; outer scales of the spikelet equal, or the sec- 

 ond a little the longer, smooth, scabrous on the keel; third scale shorter, smooth 

 and glabrous, bearing an awn 23 times its length, the basal hairs silky, erect, 

 fully as long as the scale. On prairies, Kans. (?) and Colo, to Cal. Aug. -Sept. 



7. Muhlenbergia tenuiflora (Willd.) B. S. P. SLENDER MUHLENBERGIA. 

 (I. F. f. 326.) Culms 6-9 dm. tall, erect, slender, simple or sparingly branched, 

 smooth. Sheaths usually shorter than the internodes; leaves 6.25-17.5 cm. long, 

 2-8 mm. wide, narrowed toward the base, acuminate, scabrous; panicle 1.25-2.25 

 dm. long, slender, its branches 2.5-8.75 cm. long, appressed; outer scales of the 

 spikelet unequal, half to two-thirds the length of the third one, awn-pointed, sca- 

 brous; third scale 2.5-3 mm. long, scabrous, bearing an awn 2-4 times its length. 

 In rocky woods, Mass, to southern Ont. and Minn., south to Ala. and Tex. Aug.- 

 Sept. 



8. Muhlenbergia diffusa Willd. NIMBLE WILL. DROPSEED-GRASS. (I. F. 

 f. 327.) Culms 3-9 dm. long, decumbent, or often prostrate or creeping and as- 

 cending, very slender, diffusely branched. Sheaths shorter than the internodes, 

 loose; leaves 3.75-8.75 cm. long, 1-4 mm. wide, scabrous; panicle 5-20 cm. long, 

 slender, somewhat lax, its branches 2.5-5 cm - l n g> erect, outer scales of the spike- 

 let minute, the lower one often wanting ; the third scale, exclusive of the awn, about 

 2 mm. long, strongly scabrous, particularly upon the nerves; the awn 1-4 mm. in 

 length. On dry hills and in woods, Me. and southern Ont. to Minn., south to 

 Fla., Kans. and Tex. Aug. -Sept. 



9. Muhlenbergia palustris Scribn. SWAMP MUHLENBERGIA. Culms slen- 

 der, weak, 6-io dm. long. Sheaths smooth and glabrous; leaves erect, 3-5 cm. 

 long, about 2 mm. wide, smooth beneath and rough above; panicle slender, con- 

 tracted, 1-1.5 dm. l n g> I* 3 branches appressed; spikelets, exclusive of the awn, 

 2.5-2.8 mm. long, the first scale shorter than the second, which is about one-third 

 as long as the spikelet; the flowering scale 2.3-2.5 mm. long, shortly 2-toothed at 

 the apex, bearing an awn between the teeth 5.5-8 mm. long, the callus hairy. In 

 a swamp at Washington, D. C. Sept. 



10. Muhlenbergia microsperma (DC.) Trin. SMALL-SEEDED MUHLENBER- 

 GIA. (I. F f . 328.) Culms 1.5-4.5 dm. tall, erect, finally decumbent or somewhat 

 prostrate at base, slender, diffusely branched. Leaves 1.25-6.25 cm. long, 2 mm. 

 wide or less, scabrous; panicle 5-10 cm. in length, slender, open, the branches 2.5 



