Slender Muhly

Muhlenbergia monticola Buckl. Proc. Acad. Phila. 1862:
91. 1863.
Muhlenbergia sylvatica var. flexuosa Vasey, in Rothr. Bot. Wheeler's Surv. 284. 1878. (Type from Camp Crittenden, Arizona, Rothrock 6S1.)
Perennial; culms densely tufted, slender, erect or decumbent at base, glabrous, 30-50 cm. tall, branching at thelowerand middle nodes, leafy throughout; sheaths glabrous or scaberulous; ligule acute, 2-5 mm. long; blades 3-7 cm. long, narrow, flat or soon involute, 1-2 mm. wide, slightly scaberulous; panicles soft, narrow, contracted, 5-ip, sometimes 15 cm. long, the branches appressed or slightly spreading, scabrous, floriferous from base, the axis glabrous or nearly so; glumes unequal, scabrous on the keel, acute, mucronate, or erose at tip, the first about 1.5 mm. long, the second about 2 mm. long; lemma pubescent at base and on lower half of margin, tapering into a delicate flexuous awn 1-2 cm. long.
Type locality: Western Texas {Wright 731).
Distribution: Rocky hills and canyons, western Texas to Arizona and central Mexico.

Muhlenbergia tenuifolia (H.B.K.) Kunth, Rev. Gram. 1: 63 1829.*
Calamagrostis tenuifolia H.B.K. Nov. Gen. &; Sp. 1: 134. 1815.
Calamagrostis quitensis H.B.K. Nov. Gen. & Sp. 1: 133. 1815. (Type from southern Mexico.
The specific name seems to have been given inadvertently.) Arundo tenuifolia Poir. in Lara. Encyc. Suppl. 4: 704. 1816. (Based on Calamagrostis tenuifolia
H.B.K.) Arundo quitensis Poir. in Lam. Encyc. Suppl. 4: 704. 1816. (Based on Calamagrostis quitensis
H.B.K.) Not .4. quitensis Spreng. Calamagrostis mexicana H.B.K. Nov. Gen. S: Sp. 7: Corrigenda. 1825; Kunth. Syn. PI. 4: 473.
1825. (Name substituted for C. quitensis .) Muhlenbergia (alamagrostidea Kunth, Rev. Gram. 1: 63. 1829. (Based on Calamagrostis quitensis
H.B.K.. the name presumably changed because not appropriate, the type being from Mexico,
not Quito.) Muhlenbergia longiseta Benth. PI. Hartw. 28. 1840. (Type from Aguas Calientes, Mexico, Hart'jieg
24S.) Podosaemum lenuifolium Nees; Nees & Schauer, Linnaea 19: 690. 1847. (Based on Calamagrostis
tenuifolia H.B.K.) Muhlenbergia quitensis Hitchc. Contr. U. S. Nat. Herb. 17: 292. 1913. (Based on Calamagrostis
quitensis H.B.K.)
Annual; culms slender, glabrcus, loosely ccspitose, branched from lower and sometimes from the middle nodes, widely spreading, geniculate at lower nodes, 20-70 cm. tall; sheaths mostly shorter than the internodes, glabrous or scaberulous; ligule thin, about 2 mm. long; blades flat or loosely involute, scaberulous beneath, scabrous-pubescent on the upper surface, mostly less than 10 cm. long and 1 mm. wide; panicles numerous, usually purple, terminating the culms and branches, narrow but rather loose, nodding, mostly 8-15 cm. long, sometimes longer, the axis glabrous below, scaberulous above, the lower branches distant, ascending or finally spreading, as much as 4 cm. long, usually floriferous from near base, the branchlcts and very short pedicels appressed, or in anthesis spreading, scabrous-pubescent, the upper branches shorter, contiguous, all rather densely flowered; glumes narrow, unequal, acute, more or less awn-pointed, the awns shorter than the body, the first (excluding awn) 1-1.5 mm. long, the second 1. 5-2 mm. long; lemma terete, lanceolate, 2-2.5 mm. long, about 0.3 mm. wide, pubescent at base and on the minute callus, the pubescence extending up the contiguous margins more than half way to summit, the surface otherwise minutely scaberulous; awn very slender, scabrous, flexuous, more or less crisped toward the end, mostly 1.5-2 cm. long.
Tvpii locality: Mexico C'ty.
IJISTKIBUTION: Fields, open ground, walls, gulches, and sterile soil, Mexican Plateau; .Sipiifh America (without locality, Bolivia, Bang4S7).