TRIANDRIA DIGYNIA 67 



Root perennial, creeping, nodose. Culm about 3 feet high, glabrous. Leaves 

 Hnear-lanceolate, scabrous on the margin and upper surface; sheaths striata 

 smooth : UguL short, retuse. Panicle linear-oblong, contracted, finally spreading 

 •nd somewhat nodding; branches short, semiverticillate. Glumes unequal, lower 

 one shorter than the florets. Lower pal caoflhest am incite Jl ore t with along con- 

 torted awn near the base. Loicer pa lea of the perfect Jloret mostly with a short 

 straight awn near the apex ; upper palea with a short aioi-likc rudiment at base. 



Hub. Cultivated grounds: not common. FL May. Fr. July. 



Obs. This plant was introduced to the notice of some of our farmers, a few 

 years ago, by the high-8 tunding name of "Grass of the Andes;' 9 but it did not long 

 command their altenti >n. It is. however, partially naturalized in 8< vera! neigh- 

 borhoods. I received my specimens from Gen. Ilarlman's farm, in Pike Land. 



2. A. palustris, Mx. Panicle rather loose and nodding ; spikelets 



2 to 3-flowcred : middle floret abortive, upper one pedicellate, with the 



lower palea bicuspidate, and awned below the tip ; lower floret mostly 



awn less. Jlfithl, Gram. p. 186. 



Trisetum palustre. Torr. Fl. I.j$vl26. Ejusd. Camp. p. 62. Beck, 



/Jot. p. 403. Eat. Man. p. 373. 



T. pratense. Florul. Cestr. p. 11. Also? Pursh, Am. I. p. 76. Not 



of Pers. 



Aim pallens. Ell. Sh. 1, /;. 151. Also, Afu/d. Catal. p. 11. Ejusd. 



Gram. p. 84. Not of Florul. Cestr. 



Marsh A vena. 



Root perennial. Culm 2 to 3 feet high, slender, glabrous, nodes contracted. 

 Leaves lance-linear, narrow, 2 to 4 inches long, nerved, slightly scabr us (glab- 

 rous, Mi/hi. Torr.): sheatKs striate, clabrous ; ligule oblong, lacerate, or fimbriate. 

 Panicle yell -wish green, oblong, rather loose, nodding, often somewhat secund; 

 branches semiverticillate. Spikelets all pedunculate, much compressed, gener- 

 ally 2-flowered, s in slimes with an intermediate abortive floret. Glumes nearly 

 equal, shorter than the florets, 3-nervcd, acute or mucronate, scabrous on the keel, 

 the upper one a little 1 >n<_rer. Superior Jloret on a hairy pedicel ; the lower palea 

 acuminate bicuspidate, with a contorted or bent awn, as long as the floret, inser- 

 ted below the tip; the upper palea shorter, with a pedicel or awn-like rudiment at 

 base, two thirds the Length of the palea. Loicer Jloret mostly awnless ; sometimes 

 the lower palea terminates with two minute bristly teeth, and a short, straight, 

 slender awn. 



Ilab. Swampy meadow grounds: frequent. Fl. June. Fr. July. 



Obs. From the l>"st examination I could give this plant, I have persuaded my- 

 self that it properly belongs to Arena. 



3. A. sattva, L. Panicle loose ; spikelets pendulous, 2- flowered ; 

 both florets perfect, the lower one mostly awned ; palea sub cartila- 

 ginous, closely embracing the seed. Willd. Sp. 1. p. 446. 



Common Avkxa. Vulgo — Oats. Common Oats. 



Gallice — Avoine cultivSe. German. — l)er Jfafer. Hispan. — Avena. 



"Root annual Culm 2 to 4 feet high* smooth. Leaves lanceolate, nerved; scab- 

 rous : sheaths striate, smooth, rather loose ; ligule lacerate. Panicle loose, some- 

 what nodding, spikelets all pedunculate, pendulous* Glumes nearly equal, longs/; 

 thwh the Jlorets, loose and membranous. Lower floret mostly awned on lift 



