772 ORDER 156. GRAMINE^E. 



m Awn between the 2 teeth, twisted ; glumes very large .............. DAXTHOIHA. 27 



m Awn dorsal below the middle (except in the cultivated Oat) ............. AVENA. 23 



ra Awn dorsal above the middle. Fls. 25. Teeth cuspidate ........... TRISETUM. 29 



Fls. 5 Go. Teeth acutish ............. B ROM us. 30 



TR. 8. FESTUCACE^E. (Spkl. 2 oo-fird. panicled, awnless, or the lower pale tipped with 



a straight bristle or awn. Glumes 2.) 



H 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 .......................... TRICUSPIS. 81 



q Both pales fringed, lower with 1 awn and 2 cuspidate teeth ................ UKALEPIS. 32 



r Glumes and pales keeled, herbaceous, 5-veined. Fls. glomerate ....... DACTYLIS. 38 



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



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



pale papery, gr. adherent .......... FESTUCA. 86 



E 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-veined, longer than the fls ................ ..... MELICA. 83 



8 Spikelets 2 50-fiowercd, all perfect. Pales usually thin, (u) 



u Lower pale keeled, 3-veined, membranous like the glumes .......... ERAGROSTIS. 89 



u Lower pale keeled, 5-veincd, usually cob webbed at base ..................... POA. 40 



U Lower pale convex-keeled, obscurely 9-veined. Pan. spiked ....... BEYZOPYRUM. 41 



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



u Lower pale convex-ventricous, cordate, obscurely veined .................. BRIZA. 43 



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



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



p "Woody, tall (the flowering branches low). Fls. short-awncd. . .AKUNDINAKIA. 4G 



Ta. 0. IIOEDEACEJ2. (Spkl. 1 10-fld., sessile, alternate in a spike. Eachis jointed.) 



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



V Spike single. Spikelets 1 -flowered, 3 at each joint ......................... HORDEUM. 43 



Spikelets 2 GO -flowered, several at each joint .............. ELYHUS. 49 



1 at each joint, (w) 



w Glume 1, in front of the spikelet which is edgewise to rachis ............. LOLIUM. 53 



W Glumes 2, opposite. Spikelet 3 CO -flowered ........................ TEITICUM. 51 



Spikelet 2-fiowered ............................... SECALE. 52 



TB. 10. CHLORIDES. (Spkl. in 1-sided jointless spikes, 1 co-flrd. Up. 11. abortive.) 

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



y Spikes raceme-like. Spkl. Avith several perfect fls .................. LEPTOCITLOA. 53 



y Spikes with sessile, 2-flowercd spkl., 1 fl. a rudiment .............. GYMNOPOGON. 54 



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



z Spikelets with 1 perfect flower, awnless, globular, no rudiment ....... MANISUEITS. 55 



awnless, oblong, with a rudiment ...... CYNODOX. 56 



awned, glume 8-lobed ............... EUSTACIIYS. 57 



z Spikelets with several perfect flowers. Fls. awnless ................... KLEUSINE. 53 



Fls. awned ............. DACTYLOCTEMUM. CO 



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



aa Spikes several or many. Flower with no rudiment .................. SPAKTIXA. CO 



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



aa Spiko solitary, recurved. Awns terminal and dorsal ................... CTEXIUM. C2 



TK. 11. SACCIIAHIE^E. (Spkl. in pairs or 8s, 2-llowered, the lower flower abortive. 



Fertile pales thinner than the glumes, except in No. C6.) 

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



CO Spikes monoecious, $ abortive, S below, both naked .................. TP.IPSAOUM. 63 



cc Spikes monoecious $ above panicled, 9 below enveloped in 7iusks ............ ZEA. 64 



CC Spikes uniform, terete. The pedunculate spkl. abortive .......... EOTTBCEI.LIA. 65 



compressed. Both spikelets fertile ............ STENOTAPHEUM. CG 



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



dd Both spikelets of each pair fertile. Lower fl. awned ............... EKIANTIICS. 67 



Flowers awnless .............. SACCHARUM. 68 



dd Only one spikl. of each pair fertile. Fls. and rachis hairy ........ ANDROPOGON. 69 



Fls. and rachis smoothish ....... SORGHUM. 70 



dd Tho lower spikelet on each spiko fertile, in a bony ehell ................... Coix. 71 



