ORDER 155. GRAMINE^E. 381 



9 Inflorescence paniculate. ..(3) 



2 Inflorescence strictly spicate, spikes equilateral... (5) 



2 Inflorescence strictly spicate, spikes unilateral... (6) 



3 Glumes none (or minute and the stamens 6). ..(a) Tribe 1 



3 Glumes present, at least 1 conspicuous. . .(4) 



4 Pales of the flower thin and soft, often awned... (6) Tribe 2 



4 Pales of the flower coriaceous, * tipped with awns... (/) Tribe 4 



* awnless. ..(9) Tribe 5 



i Spikes cylindric, the spikelets condensed all around... (e) Tribe 3 



Spikes nrismatic, spikelets sessile in rows...(p) Tribe 9 



6 Spikelets rounded on the back, appressed to the rachis.. .(q) Tribe 6 



6 Spikelets acutely keeled on the back, imbricated on each other... (x) ) T 'b 10 



7 Upper tis. of the spikelet abortive.* Fls. in unilateral spikes... (x) ' "" 



* Flowers paniculate... (i) Tribe 7 



7 Lower flower of the spikelet abortive. . .(8) 



8 Pales coriaceous, firmer in texture than the glumes. Paniculate... (g) Tribe 8 



8 Pales membranous, thinner than the glumes. Spicate. ..(bb) Tribe 11 



9 Flowers in 2- or 4-rowed, * equilateral spikes... (e) Tribe 9 



* unilateral spikes. ..(x) Tribe 10 



9 Flowers in panicles more or less diffuse. . .(10) 



10 Pale awned at the tip or awnless... (n) Tribe 8 



10 Pale awned on the back or below the tip...(fc) Tribe 7 



1. ORYZE.E. (Spikeleis l-jlowered, panicled. Glumes obsolete. Stamens 16.) 



a Flowers perfect, flattened laterally, awnless. Glumes 0. Stam. 2 or 3. Cut Grass LEERSIA. 1 



Glumes minute. Stamens 6. Rice ORYZA. 2 



a Flowers monoecious, both kinds in the same panicle. Stamens 6. Indian Rice. ZIZANIA. 3 



a Flowers monoecious, each kind in separate panicles. Stamens 5 12. S LUZIOLA. 4 



i. AGROSTIDE^E. (Spikelets 1-jloiccred, panicled. Glumes and pales thin. Grain frtc.) 



6 Flowers surrounded at base with a tuft of long, silky hairs CALAMAGROSTIS. 10 



b Flowers naked or thinly bearded at base. . .(c) 



c Glumes both long-awned and longer than the awned pales POLYPOGON. 9 



c Glumes both awn-pointed (or minute and the pale awned) MUHLENBERGIA. 8 



c Glumes awnless, conspicuous. . .(d) 



d Pale stalked in the glumes, awned on the back, monandroui. Siceet Reed CINNA. 7 



d Pale sess. in the glumes, 3-androus, acute, awnless. Glumes' shorter. . . . SPOUOBOI.US. 6 

 obtuse, often awned on back. Bent fa-'. .AGROSTIS. 5 



3. PHLEOIDE./E. e Glumes united at base, awnless. Pale 1, awned ALOPKCURUS. 11 



e Glumes distinct, mucronate. Pales 2, awnless. Timothy PHLEUM. 12 



e Glumes distinct, pointless. Pales 2, awnless CRYPSIS. 13 



4. STIPACE^E. / Awn of the flower simple, straight, deciduous ORYZOPSIS. 16 



/ Awn of the flower simple, twisted, very long STIPA. 15 



/ Awn of the flower triple or 3-parted. Poverty Grans ARISTIDA. 14 



6. PANICE.E. (Spikelets 2-flwd., lower flower abortive. Glumes very unequal, g Pale coriaceous) 

 g Spikelet apparently 1 -flowered, the lower glume wanting and the single abortive pale 



supplying its place. Flowers spicate, unilateral PASPALUU. 17 



Flowers diffusely panicled, all alike. Millet Grass MILTOM. 18 



Flowers paniculate, 2 sorts, one under ground AMPHICAKFUM. 19 



O Spikelet evidently 2-flowered, both glumes present, abortive flower neutral or ...(h) 



h Flowers paniculate, without awns or spines. Pale cartilaginous. Pinic G PANICUM. 20 



without awns or spines. Pales herbaceous PENICILLARIA. 21 



with the glumes and pale coarsely awned. Cock-spw. . .OPLISMENUS. 22 



h Flowers spike-panicled, each with an invol. of awned pedicels. Fox-tail SETARIA. 23 



each with a hardened, burr-like invol. Burr Grass... CENCHRUS 24 



6 PHALARIDE^E.i Sterile flowers 2 minute rudiments. Panicle spicate PHALARIS 25 



i Sterilo flowers 2 awued pales. I'anicle spicate~~^. .^AxTnoxATmnrii 26 



i Sterile flowers both 2-valved, . Panicle open HIEROCHLOA. 27 



/. AVENE^E. (Spikelete'2- <x>-floicere<l, painclf.d. Glumes large. Pale awned below thr tip.) 



fe Spikelet with 1 perfect flower and 1 awned staminate flower above. Sojl Grass HOLCUS. 28 



below ARRHENATHERUM. 31 



* Spikelet with definitely 2 perfect flowers. Pale snbentire, awn dorsal AlKA. 2J 



A Spikelet with 2 or more perfect flowers. Pale 2-toothed at tflkx. . .(TO) 



