772 ORDEB 156. GRAMINE^E. 



m A\vn between the 2 teeth, twisted ; glumes very large DANTHOXIA. 27 



m Awn dorsal below the middle (except in the cultivated Oat) A VENA. 28 



m Awn dorsal above the middle. Fls. 2 5. Teeth cuspidate TKISETUM. 29 



Fls. 5 00. Teeth aeutish BROMUS. 30 



TB. 8. FESTUCACE^E. (Spkl. 2 oo-flrd. pauicled, awnless, or the lower pale tipped with 



a straight bristle or awn. Glumes 2.) 



n Glumes definitely 2, all the lower fls. of the spkl. perfect, (o) 

 n Glumes several, indefinite, the lower fls. abort, and glume-like, (p) 

 O Lower pale 3-cuspidate at apex, fringe-bearded below, (q) 

 O Lower pale mucronato or awn-pointed (except in 1 Festuca). (r) 

 O Lower pale obtuse or acute, not at all awned. (s) 



q Upper pale naked, lower with 3 cusps and 2 teeth TUICUSPIS. 31 



q Both pales fringed, lower with 1 awn and 2 cuspidate teeth UKALEPIS. 82 



r Glumes and pales keeled, herbaceous, 5- veined. Fls. glomerate DACTYLIS. 33 



membranous, 3-veined. Pan. spicate KCBLEKIA. 34 



r Gls. and pales rounded on the back, both coriaceous. Grain free DIARRHENA. 35 



pale papery, gr. adherent FESTUCA. 86 



8 Spkl. 2 3-flrd. with some abortive terminal fls. Pale papery, not keeled, (t) 



t Upper glume broad-obovatc, shorter than the flower EATONIA. 37 



t Upper glume oblong, 7 9-veincd, longer than the fls MELICA. 88 



a Spikelets 2 50-flowered, all perfect. Pales usually thin, (u) 



U Lower pale keeled, 8-veined, membranous like the glumes ERAGROSTIS. 39 



U Lower pale keeled, 5-veined, usually cobwcbbed at base POA. 40 



U Lower pale convex-keeled, obscurely 9-vcincd. Pan. spiked BUYZOPYRUM. 41 



U Lower pale convex, 7 ( 5)-veincd, never webbed at base GLYCERIA. 42 



U Lower pale convex-ventricous, cordate, o'iscurely veined BRIZA. 43 



p Herbaceous. Fls. glabrous, awnless, falcate-pointed UXIOLA. 44 



Fls. silky-villous at base. Tall, stout PHRAGMITES. 45 



p Woody, tall (the flowering branches low). Fls. short-awned. .. AKUXDINARIA. 46 

 TB. 9. HORDE ACE.E. (Spkl. 110-fld., sessile, alternate in a spike. Kachis jointed.) 



v Spikes several. Spikl. solitary at each joint, 1 -flowered LEPTURUS. 47 



v Spike single. Spikelets 1-flowered, 3 at each joint HORDEUM. 4S 



Spikelets 2 00 -flowered, several at each joint ELYMUS. 49 



1 at each j'.iint. (w) 



W Glume 1, in front of the spikclet which is edgewiae to rachis LOLIUM. CO 



W Glumes 2, opposite. Spikelct 3 00 -flowered TRITICUM. 51 



Spikelet 2-flowered SECALB. 52 



TB. 10. CHLORIDES. (Spkl. in 1-sided jointless spikes, 1 00-flrd. Up. fl. abortive.) 

 x Spikes very slender, many, in an equilateral raceme, (y) 



y Spikes raceme-like. Spkl. with several perfect fls. LEPTOCIILOA. 53 



y Spikes with sessile, 2-flowered spkl., 1 fl. a rudiment GT.MXOPOOON. 54 



x Spikes slender, several, digitately arranged above, or, in No. 55, axillary, (z) 



Z Spikelets with 1 perfect flower, awnless, globular, no rudiment MANISURUS. 55 



awnless, oblong, with a rudiment CTNODON. 5fi 



awned, glume 3-lobed EUSTACIIVS. 57 



Z Spikelets with several perfect flowers. Fls. awnless ELEUSINE. 58 



Fls. awned DACTYLGCTEMUM. 50 



x Spikes thick and dense, 1 CO. Spikl. with 1 perfect flower, (aa) 



aa Spikes several or many. Flower with no rudiment ... SPARTINA. 60 



aa Spikes 1, few, or many. Flower with a terminal rudiment BOUTELOUA. Cl 



aa Spike solitary, recurved. Awns terminal and dorsal CTENIUM. 6J 



TR. JL SACCHAUIE^E. (Spkl. in pairs or 3s, 2-flowerod, the lower flower abortive. 



Fertile pales thinner than the glumes, except in No. CO.) 

 bb Fls. (the fertile) imbedded in the cavities of glabrous, jointed spikes, (cc) 



CO Spikes monoDcious, i abortive, 9 below, both naked TKIPS A.CUM. Co 



CC Spikes monrecious t above panicled, ? below enveloped in ftuste ZEA. 64 



CC Spikes uniform, terete. The pedunculate spkl. abortive ROTTB(ELLIA. 65 



compressed. Both spikelets fertile STENOTAPIIEUM. CG 



bb Fls. not imbedded, spicate or panicled, mostly long-bearded, (dd) 



dd Both spikelets of each pair fertile. Lower fl. awned ERIANTHTS. C7 



Flowers awnless SACCHARUM. CS 



dd Only one spikl. of each pair fertile. Fls. and rachis hairy ANDP.OPOOOX. 60 



Fls. and rachis smoothish SORGHUM. 70 



dd The lower spikclet on each spike fortile, in a bony shell Cois. 71 



