144 



GRAMINEAE. 



6. Muhlenbergia comata (Thurb.) Benth. 



(Fig. 325.) 



Hairy Muhlenbergia. 



Vaseya comata Thurb. Proc. Phila. Acad. 1863: 79. 1863. 



Muhlenbergia comata Benth.; Vasey, Cat. Grasses U. S. 39. 

 1885. 



Culms \-2% tall, erect, slender, smooth and glabrous. 

 Sheaths shorter than the internodes, smooth or slightly 

 scabrous; ligule about %" long, truncate, naked or mi- 

 nutely ciliate; leaves 2> / -5 / long, i"-z" wide, erect, 

 flat, rough; panicle often tinged with purple, 2 '-4' in 

 length, dense, branches %'-!%' long, erect; outer scales 

 of the spikelet equal, or the second a little the longer, 

 smooth, scabrous on the keel ; third scale shorter, 

 smooth and glabrous, bearing an awn 2-3 times its length, 

 the basal hairs silky, erect, fully as long as the scale. 





On prairies; Kansas (?), Colorado to California. 

 Sept. 



Aug.- 



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



(Fig. 326.) 



Agrostis tenuiflora Willd. Sp. PI. i: 364. 1798. 

 Agrostis pauciflora Pursh, Fl. Am. Sept. i: 63. 1814. 

 Muhlenbergia Willdenovii Trin. Unifl. 188. 1824. 

 Muhlenbergia tenuiflora B.S.P. Prel. Cat. N. Y. 67. 

 1888. 



Glabrous, culms 2-3 tall, erect, slender, simple or 

 sparingly branched, smooth. Sheaths usually shorter 

 than the internodes; ligule short and truncate; leaves 

 i^/i'-l' long, i // -4 // wide, narrowed toward the base, 

 acuminate, scabrous; panicle s'-o/ long, slender, its 

 branches 1'-$%' long, appressed; outer scales of the 

 spikelet unequal, half to two-thirds the length of the 

 third one, awn-pointed, scabrous; third scale iX"- 

 \%" long, scabrous, bearing an awn 2-4 times its 

 length. 



In rocky woods, Massachusetts to southern Ontario and 

 Minnesota, south to Alabama and Texas. Aug. -Sept. 



Slender Muhlenbergia. 



8. Muhlenbergia diffusa Schreb. Nimble 

 Will. Dropseed Grass. (Fig. 327.) 



Muhlenbergia diffusa Schreb. Beschr. Gras. 2: 143. pi. 51. 

 1772-9. 



Glabrous, culms i-3 long, decumbent, or often 

 prostrate or creeping and ascending, very slender, dif- 

 fusely branched. Sheaths shorter than the internodes, 

 loose; ligule short, fringed; leaves ^/t'-^/t' long, 

 # // -2 // w j(j e) scabrous; panicle 2 / -8 / long, slender 

 somewhat lax, its branches i / -2 / long, erect; outer 

 scales of the spikelet minute, the lower one often 

 wanting; the third scale, exclusive of the awn, about 

 \" long, strongly scabrous, particularly upon the 

 nerves; the awn ^"-2" in length. 



On dry hills and in woods, Maine and southern Ontario- 

 to Minnesota, south to Florida, Kansas and Texas. 

 Aug.-Sept. 



