GRAJIINE^. (grass FAMILY.) 551 



upper sheaths ; palese rough-hairy, unequal, awl-pointed, 2-3 times as long as 

 the rough-keeled glumes and linear grain. (Agrostis aspcra, il//c/ir, A. clan- 

 destina, Sprencj.) — Dry sandy soil, Florida, and northward. July and Aug. — 

 Culms -2°- 3° high. Sheaths hairy at the throat. 



2. V. vaginseflora, Ton-. Annual; culms low, clustered, bearing con- 

 cealed panicles at every joint, the teYminal one partly exserted ; leaves short, 

 smoothish ; paleaj ovate, smooth, one third longer than the smooth glumes and 

 oval grain. (Agrostis Virginica, Muhl. Crypsis Virginica, iV««. ) — Dry bar- 

 ren soil. North Carolina, and northwai'd. September. — Culms 6' -12' high. 

 Leaves 2' - 4' long. 



7. AGROSTIS, L. Bent-Grass. 



Tufted usually tender grasses, with flat and narrow leaves ; the small 1 -flowered 

 spikelets racemose on the hair-like clustered branches of the open panicle, on 

 thickened pedicels. Glumes 2, nearly equal, longer than the paleae. Palete 2, 

 the lower one commonly awned on the back, 3-5-nerved, the upper 2-nerved, 

 occasionally minute or wanting. Stamens 1-3. Styles or stigmas 2. Grain 

 free. 



§ 1. TRICHODIUM. Upper palea minute or waniinr;, the lower aivnless, shorter 

 than the unequal acute rouyh-keeled glumes. 



1- A. elata, Trin. Culms stout, erect; leaves flat (1"- 2" wiflc) ; branches 

 of the panicle flower-bearing above the middle. (A. dispar, Michx. i) — Swamps, 

 North Carolina, Curt;s. September, y. — Culms 2° -3° high. Panicles large 

 and diffuse. 



2. A. perennans, Gray. Culms slender, decumbent at the base; leaves 

 flat (l"-2"wide); branches of the panicle short, flower-bearing from below 

 the middle ; spikelets whitish. (T. pereimans. Ell.) — Swamps and river-banks, 

 Florida, and northward. July and Aug. IJ. — Culms l°-2° high. 



3. A. SCabra, WiUd. Culms slciuler, erect ; leaves short ; branches of the 

 panicle long, hair-like, hispid, bearing the purple spikelets near their summits. 

 (T. laxiflorum. Ell.) — Sterile soil, Florida, and northward. June and July. 

 (j) — Panicle usually as long as the culm. 



§ 2. AGROSTIS Proper. Upper palea man/ fest : the lower common li/ awned on 



the hack. 



4. A. alba, L. Culms ascending from a creeping base ; panicle spreading 

 in flower, contracted in fruit; glumes (whitish) nearly equal, rough-keeled; pa- 

 leae hairy at the base, the lower twice as long as the upper one, awnless or short- 

 awned. — Damp soil, Florida, and northward. Introduced. — Culms l°-3° 

 long. 



5. A. rupestris, AH. Culms slender, erect; panicle small, oblong, with 

 erect smooth branches ; glumes lanceolate, nearly equal, rough-keeled ; lower 

 palea one third shorter than the glumes, short-awned below the middle, the uppet 



one minute. — High mountains of North Carolina, and northward. July 



Culms 1° high. 



