214 



OKDEK CXL. GKAMIM i; . . IM--1 AMII.V. 



Spikeletn ill |i:ilin li N. old II linn It i null in li-il. 



nil nppareiill)- rareuioe. 



t Palea atcnltte of ei(A inconepicuotu amu. 



4. Aoaosna, Glumes equal, or the lower somewhat longer. Paleas thin, 

 not coriaceous, obtuse, upper smaller ; one often minute or wanting. Stamen* 



Dr. 



NA. Lower plume somewhat shorter than the upper one; lower 

 pale* with a short. Inconspicuous awn on the back below the tip ; upper pale* 

 1 -nerved. Stamen 1. 



6. MfiiLEXBKaoi A. Olumes usually acute or mucronate ; lower one (smaller, 

 often minute, usually shorter. Palcat mostly shorter than the glumes, sur- 

 rounded by short bain at base ; lower 8-nerved, usually mucronalo. Stamens 8. 



8. CAlAMAoaAsns. Splkclets with a rudimentary, plumoee pedicel, (;:inn<- 

 mostly nearly coual, longer than the flower. I'alcm surrounded at base by 

 a toft of white brUtlcs ; lower palea awnless, or with a rather Inconspicuous awn 

 attached to the back. Stamens 8. 



81. Mii.irw. Snfkelcta without any rudimentary pedicel ; glumes apparently 

 i, equal. Pali-e 2, coriaceous Stamens 8. 



8<X PIIAI.AKH. Bplkelets with 2 rudiments of abortive flowers, 1 on each 

 aide of the perfect flower. Paleie shorter than the equal glumes. 



1 1 Palter tcith a eontpieuotu am*. 



(. McnLricititniA. Lower glume smaller than the upper, sometimes 

 minute. Palee 2, herbaceous. Awn of the lower palea single, not jointed on 

 Its apex. 



7. BKACIITU.YTKUV. Splkcleta with the filiform pedicel of an abortive 

 flower lodged in the groove of the emarglnate, upper palea; lower glume none ; 

 upper minute. Stamens 2. 



t. Oinonis. Glumes nearly equal Paleffi equal; lower coriaceous, en- 

 veloping the upper, with the awn jointed on to the apex. Stamens 8. 



10. Aab-nriA. Qlnmes not equal, often mucronate. Lower palea with 8 

 awns at tip, much larger than the upper. 



* Flower*, primarily at li :i - 1. arranged In dimple 

 or nearly simple pike. 



t Spike simple or nearly simp/*, terminal. 



a Piu.ti-M. Spike simple, dense, cylindrical Glumes mncronate or awned. 

 Pale* both present, awnless. 



24. Ili.ittir.i-K. Splkelets In threes at each joint of the rachls. Glumes side 

 by aide, mucronate, awned. Lower palea awned at apex. 



1 1 Spttet more than one. 



11. Si-ABTixA. Spikes very densely many-flowered; few or many. In a 

 terminal raceme. Glumes acute or awned ; upper one larger than the awnless 

 palee. 



84. PAIFALVV. Splkelets loosely arranged In 2 i rows, on one side of the 

 flattened raeuis. orbicular. Spikes few. 



88. PANICUM. Flowers oolong, crowded In clusters of 2 8, In 1-sided, ap- 

 proximate, slender spikes. 



Jl. Spiteleti really t-Jtowered, the upper perfect, the lower stamlnate or 

 neutral, and in the latter cane usually reduced to a tingle palea, *o that the 

 flotcer appean to hate 2 glumtt and 8 pa'.ea. 



88. PASICCM. Splkelets single, with the terminal flower perfect, not sur- 

 rounded by bristles, arranged In racemes, panicles, or compound spikes. 



84. BETARIA. Splkelets surrounded by several or many .bristles, and ar- 

 ranged In a cylindrical more or loss compound spike. 



85. AwDRorooo*. Spikelets In pairs, one pedicellate and sterile ; the other 

 with the terminal flower perfect and awned, all arranged in ftnlkes or racemes. 



86 B6RGHI *. Spl kelets In clusters of 2 3, 1 only with the terminal flower 

 perfect and awned, the others sterile or mere rudimentary pedicels ; all ar- 

 ranged In panicles. 



87. Zti. Flowers monojclons; barren flowers In terminal, numerous spikes; 

 fertile In aolltary, lateral spikes, Inclosed In a leafy involucre of numerous bracts. 

 Styles long and slender, much exsert. 



C Splteleti really t-Jlowered, 2 of them imperfect or abortive, mottly 

 reduced to tinyle paU<r, 



98. HoLcira. Splkelcta In contracted panicles; lower flower abortive or 

 obsolete ; middle flower perfect ; upper flower staiulnate. 



49. AirrnoxAirniDK. Splkelets In nearly simple, cylindrical spikes ; the two 

 lateral flowers neutral, reduced to awned palea: ; middle flower perfect, with 

 awnless palea. 



D. Glumtt containing more than 2 Jloicen, or if only 2 lioth are perfect. 



Spikelrls in |.:iin. 1, -, ivhirh iir. often mueli con- 

 traded aind .pike-like. 



t fencer palea wl&a contpicvout aim. 



12. DACTTLB. Splkelcta 8 t-flowered. In denw, 1-lded clusters, forming a 

 crowded panicle. Glumes awned, somewhat rough and dilate on the back, as 

 alao the lower palea. 



17. FmrAcA. Bplkelcts 810 flowered, In open panicle*, or contracted, 

 nteate one*. Olumes unequal Palea) rounded on the back, entire, awned at 

 the apex. 



18. lir..'.m. Splkoleta 6 11 flowered. In loose, at length drooping panicles. 

 Olunwa unequal Lower palea mostly 2-cleft, with a straight awn In-low the tip. 



25. AlaA. Kplkelets with 2 perfect flowers, rarely a third Imperfect one. 

 Flowers balry at baae. Lover palea awned on the back below the middle. 



M. HASTHMM . H|iikelets , -flowered, In a loose, raccmow panicle. Lower 

 pale* S-toiitbed at apex, with an wn eompoeed of the three twisted nerves 

 rlatng from between the teeth. 



IT. ATEKA. rtplkrlrt* ft- .floered; uppermost Imperfect Glumes nn- 



eqiul. Lnwor palea ronmlcd on tin- back, with a twisted awn, consisting onr> 

 ( Hi,- ml. idle norro, and arising on the back below the 2-clcft tip. 



1 1 Loirrr palea ntcnla*. 



18. Oi.TctKiA. Bplkelets nearly terete, 81:1 

 .-. the rachis separating Into pleeos 

 inn -iinal, persistent after the falling of the flowers. Palen 



II. liuizorTKirM. Dlodons. Bplkelcts compreswd, 5 10-flowereil, In a 

 I'ieato panicle. Leaves revolnte. 



i. Splkelets compressed, 2 7-flowereil, In open pi- 

 with more or lew of a web-like down, but not bearded at Date. < 

 touthcd. deciduous, together with the larger, 6-nerved, lower palea. 

 KAOBosrn. Spikelets compressed, 2 40-flowi r 



. 



not webUil or bearded at base. Palrae free from the . |olet 8- 



ncrveil : upper one persistent after the rest of the flower liai fallen. 



17. Kr-Mi'-rA. t^plkoletaS 10-flowered; flowers not webbed nor bearded at 

 base. Palea rounded on the back ; upper one adhering to tin- 

 which Is somewhat downy at apex. 



1!'. 1'iiRAGiiiTES. Splkelets 8 7-flowered; flowers with a 

 beard at base ; lower flower neutral or with 1 stamen ; the others perfect with 

 8 stamens. Glumes very unequal 



.Spikelets in simple, terminal spike*. 



20. Tarncm. Splkelets 8 10-flowored, attached singly t" the join 

 rachls, with the side against It. Glumes 2, on opposite sides of the splkelet. 



21. SECAL*. Splkelets solitary at each joint of the rachb, 8 8-flowered. 

 Glumes 2 op|xlte, subulate, shorter than the flowers. 



22. LoLiru. Splkelets 6 9-flowered, solitary at the joints, and . 

 edgewise. Glume single on the outside of the spikclets, r\< t-]>t nt tlu- terminal 

 splkelet which ha/i 2. 



28. fii-Tuus. Splkelets 2 7-flowerod, In clusters of 2 4 at each joint ..i iliu 

 rachls. Glumes slue by side on Uie front of the spikclet, rarely nn< . 



1. LEfeESIA. 

 Spikclete l-flowere<l, compresscJ, perfect, in 



arranged in panicles. Palcas 2, compressed, cimimi -. a nl.--. 

 in -,-irly equal; lower broader. Stamens 1 0. Stigmas plumose, 

 Per. 



1. L. oryzoides. Cut-Graft. 



Culm rough backwards, with hooked prickles, as also the lanceolate loav.-s ; 

 panicle sheathed at base, with numerous diffuse branches; stamens 8; palcn 

 whitish, cillate on the keel A common and very rough grass in wet grounds, 

 well known by the booked prickles of its stem and leaves, which are sharp, 

 rough, and readily cut the flesh. Culm 12 It lifgh. Aug. 



2. L. Virginica. }\ r hil< (!r<t?f. 

 Culm slender, branching, gcnlcnlate or decumbent at base, clotlu-d wltli r,-- 



curved bristles at the nodes ; leaves linear-lanceolate, rough bnckw .-ml-, b ut not 

 so much as In the last ; sheaths rough backwards ; panicle simple ; flowers ap- 

 pressed on the slender branches; stamens 2; paleie greeubh, slightly cillate. 

 A more slender species than the last, with the stem and leaves much less rough) 

 and a simpler panicle. Culm 15' 2U' high. Aug. 



2. ZIZAXIA. 



Flowers monoecious. Spikclcts 1-flowcrcd, both kin.ls in tlio 

 game panicle. Glnmes miwtlj' wnntinp. 1'alc.r of llir luin-.-n 

 flowers awnless, of the fertile, with a straight awn. 

 Styles 2. Per. 



1. Z. aqudtica. l,i,li,i,i i 



Culm hollow, smooth, tall; leaves flat, very lone, llnear-lai- 

 serrulate ; panicle very large, pyramidal ; lower branches spreading, stamina! i- ; 

 upper branches erect, pistillate ; pedicels of the pl.-IIIIalo flowers clava!< 

 palea with a long awn; grain linear. A tall, aquatic grase, on tl 

 borders of streams, and of swamps, salt or fresh. Culm 4 S ft. high. Tim 

 spikelcts and fruit are wry declduoua. Bather common. July Aw. 



::. rm.KUM. 



Glumes 2, curinato, much longer than tin- |.:ilr.v. niiirriiiiitti-nr 

 nwncd. Paleee 2, uiiiMjunl, li-un<-at'-, im Imli-il in Ihc glumes. 

 Stamens 3. J'T. 



1. P. pratensc. Timothy. Herd's Gruff. 



Ciilui erect, simple, smooth, sometimes bulbous at base; leaves flat, glau- 

 cous; flowers In a long, dense, simple, terminal, cylindrical spike; glumes dil- 

 ate on the back, truncate, tipped with a very fliort awn ; anthers purpl 

 very valuable speck*, frequently cultivated for bay, and thoroughly naturalized. 

 Culm 24 ft high. June July. 



4. AGBOSTI3. 

 l-ll"iTed, paniculate. Glumea 2, subc<(iiul, .<r ilic 



