i6o 



GRAMINEAE. 

 Rough-leaved Bent-grass. (Fig. 363.) 



2. Agrostis exarata Trin. 



Agrostis exarata Trin. Unifl. 207. 1824. 

 Agrosiis asperifolia Trin. Mem. Acad. St. Petersb. 

 (VI.) 6: Part 2, 317. 1845. 



Culms i-3 tall, erect, or sometimes decumbent 

 at the base, simple, smooth and glabrous. Sheaths 

 usually shorter than the internodes, smooth or 

 roughish; ligule i // -3^ // long, more or less decur- 

 rent; leaves i / -8 / long, i // -4 // wide, generally erect, 

 flat or involute, scabrous; panicle contracted, 2)^'- 

 10' in length, often interrupted or glomerate, the 

 branches i^'-^' in length, erect, spikelet-bearing 

 to the base; spikelets crowded, i // -2 // long, the 

 outer scales subequal, scabrous, especially on the 

 keel; third scale from less than one-half to three- 

 fourths the length of the second, obtuse or sub- 

 acute; palet minute. 



Manitoba to Alaska, south. to Wisconsin, Nebraska, 

 Texas and California. Aug. -Sept. 



3. Agrostis Elliottiana Schultes. Elliott's Bent-grass. (Fig. 364.) 



Agrostis arachnoides Ell. Bot. S. C. & Ga. i: 134. 



1817. Not Poir. 1810. 

 Agrostis Elliottiana Schultes, Mant. 2: 202. 1824. 



Culms 5 / -i4 / tall, erect, slender, simple, smooth 

 and glabrous. Sheaths shorter than the internodes, 

 smooth or slightly scabrous, strongly striate; 

 ligule \" long; leaves rough, YZ'-^' long, i /A 

 wide or less; panicle 2 / ~5 / in length, usually 

 narrow, sometimes open, the branches slender, 

 naked below, erect or ascending, the lower I'-i^' 

 long; spikelets ^ ff long; outer scales subequal, 

 scabrous on the keel, acute; third scale about three- 

 quarters as long as the first, erose-truncate, acute or 

 2-toothed, bearing a very finely filiform flexuous 

 barbellate awn, 2-4 times its length, inserted just 

 below the apex; palet short. 



In dry soil, South Carolina to Kentucky and Mis- 

 souri, south to Florida and Texas. May-July. 



4. Agrostis canina I,. Brown Bent-grass. .(Fig. 365.) 



Agrostis canina I,. Sp. PI. 62. 1753. 



Culms i-2 tall, erect, slender, simple, smooth and 

 glabrous. Sheaths shorter than the internodes; ligule 

 W-\ l A"\on%\ leaves i'-3' in length, i" wide or less, 

 scabrous; panicle i'--]' in length, contracted in fruit, 

 the branches slender, naked below, ascending or 

 spreading in flower, the lower i'-2 l A' long; spikelets 

 i" long, on appressed pedicels, the outer scales sub- 

 equal, acute, strongly scabrous on the keel; third scale 

 about two-thirds the length of the first, obtuse, smooth 

 and glabrous, bearing a straight or somewhat bent 

 dorsal awn i"-2" long, inserted just above the middle; 

 palet minute or none. 



In meadows, Newfoundland to Alaska, south to Penn- 

 sylvania and Tennessee. Native northward; naturalized 

 om Europe southward. A variable species. July-Sept. 



