1 "Mature spikelets falling entire from their pedicels (except for Arundinella and more or less persistent on a flat, indistinctly and tardily disarticulating rachis as in Stenotaphrum), all alike or differing in sex, size, shape, or structure; fertile spikelets usually with 2 florets, the upper bisexual or female, the lower male or sterile (rarely both bisexual as in Isachne spp.); rachilla not produced beyond the upper floret; lower glume occasionally suppressed." 2 1 "Mature spikelets mostly breaking up above the more or less persistent glumes or, if falling entire, then neither 2-flowered nor with the upper floret bisexual and the lower floret male or sterile; spikelets 1–many-flowered; rachilla often produced beyond uppermost floret." 67 2 "Male and female spikelets in separate inflorescences or in different parts of the same inflorescence and different in appearance; lemmas hyaline or membranous and thinner than the glumes." 3 2 "Spikelets all bisexual or with male, sterile and bisexual spikelets mixed in the inflorescence and so arranged that a male or sterile spikelet is near a bisexual spikelet or, if spikelets all unisexual, then the lemma of the fertile floret hardened." 4 3 "Male and female spikelets in different inflorescences on the same plant." Zea 3 "Male and female spikelets separated but in the same inflorescence; female spikelet surrounded by a hardened utricle." Coix 4 "Spikelets usually in pairs or threes with 1 sessile and the other(s) pedicellate, or more rarely both pedicellate with 1 shorter and the other longer pedicellate or rarely the pedicellate spikelet reduced to the pedicel or absent, those of each pair or trio alike in sex or different, falling entire at maturity; glumes often more or less rigid or at least firmer and longer than the lemmas (excluding awns); lemmas membranous or hyaline; in the bisexual or female spikelets the upper lemma often awned with an usually geniculate awn or the awn reduced or absent." 5 4 "Spikelets solitary, or if in pairs or threes then all virtually similar; glumes usually herbaceous or membranous, more rarely hardened, the lower glume usually smaller than the upper or sometimes completely suppressed; lower lemma (mostly sterile) usually resembling the upper glume in texture and often in size; upper lemma from papery to very tough and rigid, rarely hyaline (Neurachne, Thyridolepis), usually awnless (occasionally mucronate)." 31 5 "Internodes of the raceme axis and also the pedicels stout, more or less thickened upwards, 3-angled or rounded, often more or less hollowed out on one side." 6 5 "Internodes of the raceme axis and pedicels slender, cylindrical or flattened; lower floret of sessile spikelet sterile." 11 6 "Lower glume fringed on the keels with stiff scabrid, antrorsely-curved spines; raceme solitary, terminal, 1-sided; the sessile spikelets overlapping, accompanied by a pedicel that may or may not bear a rudimentary spikelet." Eremochloa 6 "Lower glume not fringed with stiff spines; raceme various." 7 7 "Internodes and pedicels fused to form roughly semi-cylindric internodes." 8 7 "Internodes and pedicels not fused together." 9 8 "Spikelets of each pair more or less similar." Hemarthria 8 "Pedicellate spikelet of each pair male or sterile." Rottboellia 9 "Racemes paired or digitate [rarely solitary]; lower glume of sessile spikelet more or less winged on the keels, the upper not awned; pedicels inflated." Ischaemum 9 "Racemes solitary; lower glume of sessile spikelet not winged, the upper awnless or awned; pedicels not inflated." 10 10 "Lower glume of sessile spikelet fringed with stiff hairs and apex elongated into two (sometimes partly fused) awn-like teeth or lobes as long as the body of the glume; upper glume awnless." Elyonurus 10 "Lower glume of sessile spikelet not fringed with stiff hairs and 2-toothed without an awn-like process; upper glume awned." Sehima 11 "Spikelets of each pair alike in sex and shape." 12 11 "Pairs (or threes) of spikelets dissimilar in sex and more or less in shape (or if those of some pairs of a raceme are alike then both male or sterile); fertile spikelets usually awned." 17 12 "Spikelets all pedicellate, 1 of each pair shortly, the other longer pedicellate." 13 12 "One spikelet of each pair sessile, the other pedicellate; spikelets awned." 14 13 "Spikelets awnless; panicles spicate, dense, whitish; culms from a long, creeping rhizome; blades narrow at the base." Imperata 13 "Spikelets awned; inflorescence of few–many racemes 10–25 cm long, much exceeding the primary axis; robust, caespitose perennial with linear leaves." Miscanthus 14 "Culms more than 1.5 m high when mature, with many-noded culms more than 2 cm diam.; leaves usually more than 5 cm wide; inflorescence large, paniculate, white; fertile lemma with a straight, short, terminal awn." Saccharum 14 "Culms less than 1.5 m high, culms with few nodes and less than 1 cm diam.; leaves less than 2 cm wide." 15 15 "Spikelets unawned though the apex of the lower glume of sessile spikelet with two (sometimes partly fused) awn-like teeth longer than the body of the glume." Elyonurus 15 "Spikelets awned; apex of lower glume without awn-like teeth." 16 16 "Caespitose perennial with narrow-linear leaves; racemes digitate or subdigitate, silky-villous with yellowish hairs." Eulalia 16 "Slender decumbent annual with lanceolate leaf blades; racemes 3–6, somewhat distant on a short axis, not manifestly villous." Microstegium 17 "Upper lemma of fertile spikelets awned from low down on the back; pedicellate spikelets reduced to their pedicels or these also absent and the sessile spikelets solitary; slender decumbent grass, rooting at the nodes, with lanceolate, cordate leaf blades." Arthraxon 17 "Upper lemma of the sessile spikelet awned from the tip or 2-toothed or 2-lobed and awned from the sinus, rarely awnless; caespitose grasses." 18 18 "Racemes in more or less compound espatheate panicles with the more or less elongated branches usually opposite or whorled on a more or less elongated axis." 19 18 "Racemes either espatheate and solitary, digitate or subdigitate, or in spatheate panicles." 23 19 "Joints and pedicels without a longitudinal depression, usually circular or elliptic in cross section." 20 19 "Joints and pedicels with a longitudinal depression, dumbbell-shaped in cross section." 22 20 "Sessile spikelets and grain more or less dorsally compressed at least when in flower, the lower glume never scabrous on the keels." Sorghum 20 "Sessile spikelets and grain more or less laterally compressed, the lower glume more or less scabrous on the keels." 21 21 "Racemes with 1 or 2 (rarely 3) joints (nodes), if regularly more than 1-jointed then the awn geniculate and twisted with a prominent column; leaf blades involute or convolute." Chrysopogon 21 "Racemes with 3–several joints (nodes) rarely less in the same panicle; awn bristle-like without a distinctly differentiated column, or absent; leaf blades flat or folded, the sheaths keeled." Chrysopogon 22 "Racemes with 1–8 joints (nodes); panicle open with capillary branches." Capillipedium 22 "Racemes with more than 8 joints; inflorescence of racemes on an elongated axis." Bothriochloa 23 "Racemes espatheate, digitate or subdigitate, rarely solitary; fertile spikelets dorsally compressed and the lower glume more or less 2-keeled, the callus short and obtuse; awn glabrous; culms simple or branching from the lower nodes." 24 23 "Racemes spatheate or gathered into spatheate panicles." 25 24 "Joints and pedicels with a longitudinal depression, dumbbell-shaped in cross section; racemes without spikelets at the base, the lower sessile spikelets all fertile and awned." Bothriochloa 24 "Joints and pedicels without a longitudinal depression, circular or elliptic in cross section; racemes sessile with the sessile spikelets of the lower 1–3 pairs sterile and awnless." Dichanthium 25 "Racemes falling entire at maturity either separately or together with their spathes, consisting of only 1 fertile spikelet subtended by a false involucre of sterile spikelets." Iseilema 25 "Racemes breaking up at maturity, the spathe and sometimes the lower (and then sterile) part of the raceme persistent." 26 26 "Fertile spikelet more or less terete (slightly flattened dorsally in Hyparrhenia), usually with a more or less pungent callus; awn, or at least its column, hairy; lower 1–few pairs of spikelets usually sterile." 27 26 "Fertile spikelet either dorsally or laterally compressed, the lower glume more or less 2-keeled; callus short and obtuse; fertile lemma 2-fid and awned from the sinus, the awn usually glabrous." 29 27 "Basal sterile spikelets forming a false involucre around the fertile spikelet on the 1-jointed (noded) racemes solitary in the ultimate spathes." Themeda 27 "Basal sterile spikelets not forming an involucre around the fertile spikelet; culms much branched from the upper nodes." 28 28 "Racemes paired on very slender peduncles in the ultimate spathes; callus subacute or acuminate." Hyparrhenia 28 "Racemes solitary on the ends of the culm branches, secund, the bases of the sterile spikelets subimbricate on the back of the raceme; callus very pungent." Heteropogon 29 "Racemes solitary on each peduncle, the rachis very slender and fragile." Schizachyrium 29 "Racemes in pairs or more or less digitate on each peduncle, the rachis not as slender or fragile." 30 30 "Racemes 2–4 on each peduncle, approximate or at length somewhat diverging, the rachis slender and fragile; pedicellate spikelet reduced to its pedicel." Andropogon 30 "Racemes 2, at first approximate but soon sharply deflexed, the rachis less markedly slender and fragile; pedicellate spikelets developed." Cymbopogon 31 "Spikelets disarticulating above the glumes." Arundinella 31 "Spikelets disarticulating below the glumes." 32 32 "Spikelets virtually all bisexual." 33 32 "Spikelets unisexual and the plants dioecious, the spikelets in more or less dense heads subtended by bracts, the female heads globose or hemispherical." 66 33 "Spikelets dimorphic, some chasmogamous on simple, spicate, terminal racemes, others cleistogamous, compressed; rigid, branching perennials." Cleistochloa 33 "Spikelets virtually all alike." 34 34 "Fertile lemma densely hairy with fine, white, more or less appressed hairs." Entolasia 34 "Fertile lemma glabrous on the back." 35 35 "Main axis of the panicle or racemes not disarticulating and the racemes persistent on the main axis, the spikelets not falling attached to the segments or, if so, then the spikelets or groups of spikelets variously subtended by bristles or by a spiny or bristly involucre." 36 35 "Main axis of the more or less spicate panicle readily or tardily or partially disarticulating into segments, the spikelets not subtended by bristles or an involucre." 65 36 "Spikelets not subtended by bristles or an involucre (rarely subtended by a corona of very short, fine hairs)." 37 36 "Spikelets (or some of them) or groups of spikelets subtended by 1 to several bristles that may be simple or fused into an involucre, or by branches bearing groups of bristles." 61 37 "Fertile lemma and palea not much harder than, or softer than the glumes." 38 37 "Upper lemma more or less thickened or indurate, or if subhyaline then the upper glume and sterile lemma acuminate or tapering into long points and the panicle branches produced beyond the uppermost spikelet, or else the spikelets concealed amongst silky hairs." 41 38 "Low spreading stoloniferous perennial in saltmarsh with leaf blades less than 2 mm wide." Alexfloydia 38 "Ceaspitose or stoloniferous perennials; if stoloniferous then leaves more than 3mm wide and not growing in saltmarshes." 39 39 "Spikelets less than 3 mm long, lower lemma shortly awned between 2 lobes; leaves sticky." Melinis 39 "Spikelets more than 3 mm long, lemmas awnless; leaves not sticky." 40 40 "Lower glume with a depressed vertical window surmounted by a thick transverse ridge bearing bristles." Thyridolepis 40 "Lower glume without a 'window' or ridge with bristles." Neurachne 41 "Glumes and sterile lemma with spreading, hooked or curved, tubercle-based hairs; fertile lemma thinly cartilaginous with flat hyaline margins; rigid, branching perennials almost shrubby or scrambling." Ancistrachne 41 "Glumes and lemma without spreading hooked or curved hairs." 42 42 "Both florets fertile, or if the lower floret male then its lemma very similar to the upper and hardened; glumes more or less equal and similar; spikelets globose, small, awnless." Isachne 42 "Lower floret male or sterile, its lemma usually differing in texture or size from the lemma of the upper floret; glumes usually unequal or dissimilar (rarely subequal and similar as in Ottochloa and then the spikelets not distinctly globose), the lower (very rarely both) suppressed." 43 43 "Lower glume rudimentary and forming, with the base of the rachilla, a swollen annular callus subtending the lower glume; fertile floret hardened, usually with a small apical mucro." Eriochloa 43 "Spikelet not subtended by a swollen annular callus." 44 44 "Fertile lemma thinly cartilaginous to indurate with more or less flat, thin or hyaline margins enveloping the margins of the palea; spikelets borne on (1-or) few–many-flowered spicate racemes that are digitately, subdigitately or racemosely arranged on a common axis, or rarely solitary." 45 44 "Either the fertile lemma with more or less inrolled thickened margins or the spikelets not borne on slender racemes on a common axis, or both." 47 45 "Lower glume subequal to the spikelet; sterile lemma with a subequal palea." Homopholis 45 "Lower glume less than 60% the length of the spikelet; sterile lemma with a minute scale-like palea that often remains attached to the base of the fertile floret." 46 46 "Fertile lemma shortly awned, the margins firm but thinner than the back; sterile lemma thinly cartilaginous like the fertile; upper glume densely ciliate along the outer nerves, the rigid cilia at first appressed then later spreading." Alloteropsis 46 "Spikelets unawned, occasionally the fertile lemma terminating in a very minute inconspicuous mucro; fertile lemma with thin, flat, hyaline margins; indumentum various but the upper glume not, and the sterile lemma very rarely, ciliate." Digitaria 47 "Spikelets awnless; fertile lemma rugulose or smooth." 48 47 "Either the glume(s) and/or the sterile lemma awned or mucronate, or the partial rachis produced into a long, awn-like point beyond the uppermost spikelet and then the upper glume and fertile lemma long acuminate; fertile lemma smooth." 58 48 "Inflorescence of variously arranged (rarely solitary), simple or compound, usually more or less secund, often spicate, dense or loose racemes, not an open, or contracted and cylindrical, panicle; spikelets often in pedicellate pairs or threes or solitary, alternately to the left and right of the median line of a usually triquetrous or compressed, dorsiventral rachis." 49 48 "Inflorescence either an open panicle or else contracted, cylindrical and spicate." 56 49 "Back of the fertile lemma abaxial, the lower glume (if present) adaxial." 50 49 "Back of the fertile lemma adaxial, the lower glume (if present) abaxial." 52 50 "Lower glume absent; racemes digitate or subdigitate." Axonopus 50 "Lower glume present and well developed; racemes arranged racemosely along the main axis." 51 51 "Upper lemma smooth and shiny, neither awned nor apiculate." Brachiaria 51 "Upper lemma coarsely or finely rugose or rugulose, usually awned or apiculate." Urochloa 52 "Rachis of the racemes produced into a distinct short bristle beyond the uppermost spikelet; spikelets often very convex on the back and more or less depressed on the face, secund on the short, slender, sessile, spicate racemes." Paspalidium 52 "Rachis of the racemes not produced into a bristle beyond the uppermost spikelet." 53 53 "Lower glume little shorter than the upper and similar in appearance, both glumes shorter than and exposing the fertile lemma; margins of the fertile lemma very narrowly hyaline and minutely ciliolate upwards, entirely covering the tip of the palea; delicate decumbent or scrambling perennials." Ottochloa 53 "Lower glume very much shorter than the upper or absent; spikelets shortly to very shortly pedicellate and usually more or less crowded or secund, spicate racemes." 54 54 "Lower glume generally absent." Paspalum 54 "Lower glume present." 55 55 "Fertile lemma rugose, very obtuse with an abrupt, usually scabrous or barbellate mucro; spikelets more or less flattened, glabrous or softly hairy." Urochloa 55 "Fertile lemma smooth and shining, acute or acuminately pointed, the margins inrolled below but more or less flat above and not enclosing the tip of the palea; spikelets turgid, often stiffly hispid." Echinochloa 56 "Inflorescence a contracted, cylindrical, spicate panicle; spikelets gibbous." Sacciolepis 56 "Inflorescence a large or small, more or less open panicle; spikelets not gibbous." 57 57 "Low spreading stoloniferous perennials in saltmarsh with leaf blades less than 2 mm wide; spikelets often appearing laterally flattened; inflorescences 3–6-flowered, the spikelets 3–4 mm long." Alexfloydia 57 "Caespitose or stoloniferous annuals or perennials; if stoloniferous perennials then leaf blades more than 2 mm wide, the spikelets usually appearing dorsiventrally flattened and more than 6 per inflorescence, and less than 3 or more than 4 mm long." Panicum 58 "Upper glume and sterile lemma concealed by copious, long, silky hairs and somewhat gibbous about the middle, awned from the slightly notched tip, laterally compressed; panicles spreading." Melinis 58 "Upper glume and sterile lemma glabrous or pubescent but not concealed by long silky hairs." 59 59 "Glumes subequal, herbaceous, the lower awned from the back of an entire apex; spikelets in small clusters or 1- or 2-nate, secund on more or less short, spicate racemes that are racemosely arranged on a common axis; weak ascending grasses with slender, several-noded culms and lanceolate leaves." Oplismenus 59 "Glumes very unequal, the lower not or scarcely awned; awns terminal (if present) on the upper glume and/or sterile lemma." 60 60 "Rachis not conspicuously produced beyond the uppermost spikelet; upper glumes and sterile lemma both usually hispid with more or less stiff or bristly hairs; upper floret bisexual; spikelets crowded in rows or irregularly along mostly simple, 1-sided, spicate branches of a panicle." Echinochloa 60 "Rachis conspicuously produced into a long awn-like point beyond the uppermost spikelet; upper floret usually female, much shorter than the lower male floret; panicles either loosely spicate or spreading." Pseudoraphis 61 "Spikelets solitary or several together in racemes distant along the axis and the racemes (or solitary spikelets) disarticulating as a whole from the main axis." 62 61 "Spikelets solitary or in clusters on the branches of more or less contracted, spicate (rarely open) panicles, the spikelets or clusters falling from the (common) pedicels." 63 62 "Spikelets several together on the racemes, the lowest or lower subtended by a bristle (the prolongation of the rachis of a reduced lateral branch) and the rachis prolonged as a bristle beyond the uppermost spikelet." Paractaenum 62 "Spikelets solitary on the branches and subtended by 3 or 4 sterile branches that terminate in bristle-like branches, very rarely bearing a second spikelet." Plagiosetum 63 "Bristles (rarely 1–few) persistent on the pedicels, the spikelets deciduous." Setaria 63 "Bristles or involucre falling with the spikelets at maturity." 64 64 "Bristles not united at the base, slender, smooth, antrorsely scabrous, ciliate or plumose, the spikelets solitary or in groups of 2–5." Pennisetum 64 "Bristles united into a burr-like involucre (more rarely only slightly united at the base) around a solitary spikelet or group of 2–7 spikelets." Cenchrus 65 "Spikelets falling entire (sometimes tardily) from the rudimentary pedicels, solitary or 2–5 (rarely more) on short spicate racemes that are more or less sunk in hollows (or at least closely appressed) on 1 side of a flattened, or spongy continuous or jointed common axis; stoloniferous perennials with rather broad, obtuse blades and short flowering culms; spikelets rarely maturing seed." Stenotaphrum 65 "Spikelets sessile, few together (usually 2–4) on short spikes on a readily disarticulating, flattened common axis, the spikes falling entire with a segment of the axis; annual." Uranthoecium 66 "Female heads about 2.5–3.5 cm diam., slightly bristly with the curved points of the bracteoles; male heads globose or hemispherical, 1–2 cm diam., the lowermost bract usually exceeding the head; rigid, branched bushy hummock-forming grass to 1.5 m high with stout creeping rhizomes; lunettes of inland lakes and inland sand dunes." Zygochloa 66 "Female heads large, about 20–30 cm diam., each spikelet solitary at the base of a long, spicate rachis; male spikelets few–many in sessile or pedunculate spikes clustered in a terminal head and often with other heads lower down on the stem, each spike about 2–4 cm long; plants forming tufts with long, trailing stolons on coastal sand dunes." Spinifex 67 "Shrubs or trees with woody, often tall persistent culms, very rarely perennial herbs; leaf blades flat, many-nerved, often with manifest transverse veins, usually with a petiole-like base and articulated with the sheath." 68 67 "Perennial or annual herbs with herbaceous or rarely somewhat woody culms; leaf blades usually sessile and not articulated with the sheaths, very rarely with a petiole-like base." 70 68 "Rhizomes short, pachymorph ('non-running') forming dense slow-growing clumps." Bambusa 68 "Rhizomes elongate, leptomorph ('running') forming extensive stands." 69 69 "Internodes more or less cylindrical." Arundinaria 69 "Internodes distinctly grooved." Phyllostachys 70 "Spikelets sessile or shortly pedicellate along 1 side of the rachis of digitate, solitary or scattered spikes or spicate racemes." 71 70 "Spikelets borne in open or contracted spicate panicles, less often in racemes or spikes but then the spikelets on both sides of the axis." 79 71 "Spikelets with 1 fertile floret, with or without 1 or more imperfect florets above it." 72 71 "Spikelets with 2 or more fertile florets." 76 72 "Fertile floret with 1 or more imperfect floret(s) above it; lemmas usually awned or mucronate." 73 72 "Fertile floret without an imperfect floret above it though often the rachilla produced and rarely bearing a minute abortive floret; lemmas usually not awned." 75 73 "Glumes subequal, the upper mucronate; lemmas awnless or mucronate." Eustachys 73 "Glumes unequal, acute, acuminate or aristulate; lemmas awned." 74 74 "Lemmas laterally compressed." Chloris 74 "Lemmas dorsally compressed." Enteropogon 75 "Glumes longer than the floret." Brachyachne 75 "Glumes shorter than the floret." Cynodon 76 "Axes of the spikes producing a bristle or acute point." Dactyloctenium 76 "Axes of the spikes ending in perfect or aborted spikelets, not projecting as a sterile bristle." 77 77 "Lemmas prominently lobed with the central segment tapering into a short, stiff, straight or terminally hooked awn." Astrebla 77 "Lemmas truncate, entire, erose or mucronate but not prominently lobed." 78 78 "Lemmas entire, acute." Eleusine 78 "Lemmas truncate or erose or minutely notched, rarely mucronate." Leptochloa 79 "Spikelets with 1 fertile floret, with or without 1 or 2 male or sterile florets below it." 80 79 "Spikelets usually with 2 or more fertile florets, or if with 1 fertile floret then with sterile florets above it." 110 80 "Stamens 3, 4 or 2; palea 2-nerved (except nerveless and without keels in Nassella); glumes (or at least the upper glume) well developed or occasionally minute." 81 80 "Stamens usually 6; palea 3–9-nerved; glumes very small and hyaline or reduced to an obscure rim at the apex of the pedicel or suppressed; aquatic grasses." 108 81 "Spikelets with 1 or 2 florets; glumes (or at least the upper) well-developed." 82 81 "Spikelets with 3 florets, the terminal floret bisexual, the lower 2 florets male or sterile and sometimes reduced to small or minute scales, articulate above the glumes, the florets falling together; glumes well developed or minute." 103 82 "Spikelets falling entire at maturity, either singly or in clusters, from the axis of slender, spicate panicles or racemes; lemmas delicate, 1–3-nerved." 83 82 "Spikelets usually breaking up at maturity, the rachilla disarticualting above the more or less persistent glumes, or if falling entire then with firmly membranous awned or 5-nerved lemmas." 85 83 "Spikelets in deciduous, burr-like clusters of 2 (in the N.S.W. species) to 6; lower glume minute or suppressed; upper glume 5-nerved and hispid or spinous with hooked spines on the nerves." Tragus 83 "Spikelets borne singly or very shortly pedicellate on the continuous axis of a solitary, terminal spike or spicate raceme." 84 84 "Lower glume absent; upper glume awnless or mucronate or with a very slender awn to 3 mm long; low, rhizomatous or stoloniferous perennials." Zoysia 84 "Glumes more or less equal and similar, tapering into long capillary awns; annual (in the N.S.W. species)." Perotis 85 "Lemmas more or less hardened and rigid at maturity, more or less terete or slightly dorsally compressed, with convolute or involute margins tightly enveloping the grain, with a terminal awn or awns or cleft into usually awned segments, rarely awnless." 86 85 "Lemmas hyaline or membranous at maturity and awnless or dorsally (sometimes only slightly so, almost subterminally) awned, or more rarely terminally awned from the entire and obtuse or minutely toothed apex, or if the lemma hardened then the awn clearly dorsal or the glumes ciliate on the keels or the spikelets and lemmas more or less laterally compressed." 92 86 "Lemma terminating in a single undivided awn." 87 86 "Lemma 3–5-cleft or 3–5-awned, or terminating in a single awn that branches above into 3 awns." 89 87 "Lemma usually several times longer than broad, narrow, cylindrical, sometimes slightly gibbous, tapering at the tip or sometimes slightly 2-lobed, convolute and totally enclosing the palea; awned from the apex of the lemma or from between its lobes, more or less persistent or tardily deciduous, twisted in the lower part, usually once or twice geniculate; callus longer than the breadth of the lemma, very oblique, sharp-pointed and bearded." Stipa 87 "Lemma short and broad; awn slender, deciduous; callus shorter than the breadth of the lemma." 88 88 "Lemma elliptic-oblong, not gibbous at the top; awn terminal and central from the minutely-lobed apex, straight, deciduous; palea 2-nerved, shorter than or subequal to the lemma." Piptatherum 88 "Lemma asymmetric, gibbous at the summit; awn eccentrically attached, deciduous; palea short, hyaline, without nerves or keels." Nassella 89 "Lemma 5-awned, the central awn stronger than the laterals, geniculate and twisted below the bend, the 4 lateral awns slender, straight or curved but not twisted." Pentapogon 89 "Lemma 3-cleft or 3-awned or the single awn 3-branched." 90 90 "Lemma deeply 3-cleft with each segment usually awned; body of the lemma shortly oblong or ovate, with a short, obtuse or scarcely pointed callus (in the N.S.W. species); palea deeply 2-cleft with each segment usually awned similarly to the lemma." Amphipogon 90 "Lemma 3-awned or the single awn 3-branched, cylindric or linear oblong with a pointed callus; palea not deeply cleft." 91 91 "Awns (or branches) more or less similar (at least in the N.S.W. species), straight or somewhat curved; lemma tightly convolute or pseudo-involute, concealing the palea; rachilla not produced above the fertile floret; glumes 1-nerved (rarely to 5-nerved)." Aristida 91 "Awns very unequal, the central much longer, very robust and geniculate and twisted below the bend, the laterals slender, straight or curved and not or scarcely twisted; lemma convolute, at the apex not concealing the palea which extends beyond the point of insertion of the awns; spikelets very large, the glumes 3–5.5 cm long and more than 5-nerved; rachilla produced beyond the fertile floret, sometimes bearing an aborted floret." Anisopogon 92 "Lemmas 1–3-nerved, awnless; glumes and lemma very similar in texture, thinly to very firmly membranous or hyaline, often somewhat shining; grain free (at maturity) in a delicate pericarp, falling free from the lemma and palea." Sporobolus 92 "Lemmas usually 3–5-nerved, frequently awned; glumes differing in texture from the lemma, usually longer and firmer than the hyaline lemma, but if shorter than the lemma or if the lemma is hardened then the glumes membranous and dull; grain usually with an adhering pericarp." 93 93 "Rachilla disarticulating below the glumes, the spikelet falling entire at maturity; panicles dense and spicate." 94 93 "Rachilla disarticulating above the glumes." 96 94 "Glumes both awned from the entire apex or from the sinus between the 2 obtuse, short lobes of the apex, the awns very delicate, 4–7 mm long; lemma very thin, with a broad, blunt, minutely toothed tip, awnless or with an awn to 2 mm long from the tip." Polypogon 94 "Glumes awnless, lemma membranous with a slender dorsal awn." 95 95 "Glumes more or less ciliate on the keel; inflorescence dense and spicate." Alopecurus 95 "Glumes not ciliate on the keels; panicle open or dense and contracted but not spicate." Agrostis 96 "Glumes either feathery-hairy, or glabrous, swollen, hardened and shining at the base." 97 96 "Glumes neither feathery-hairy nor swollen at the base." 98 97 "Glumes feathery-hairy, each tapering into a fine bristle; panicle dense, spicate, globose to ovoid or oblong-cylindrical; lemma narrowed into 2 teeth and bearing a dorsal geniculate awn." Lagurus 97 "Glumes glabrous, acuminate, at the base swollen, hardened and shining; lemma very blunt, minutely toothed, awnless or with a slender, dorsal, geniculate awn; panicles narrow-lanceolate, oblong or cylindrical, dense and spicate." Gastridium 98 "Glumes abruptly truncate with a short, rigid awn 1–2 mm long produced at the tip above the keel (in the species in N.S.W.), the keels fringed with cilia; spikelets oblong, very flattened, tightly packed in a dense, spicate, cylindrical panicle; lemma membranous, very blunt, awnless." Phleum 98 "Glumes obtuse, acute or acuminate but not abruptly truncate, and not or scarcely awned." 99 99 "Lemmas membranous or at least very thin, obtuse or truncate, smooth or softly hairy; panicles spreading or contracted but not or scarcely spicate; spikelets (at least in the N.S.W. species) less than 8 mm long; palea as long as to much shorter than the lemma or absent." Agrostis 99 "Lemmas thinly papery to hardened, more or less scaberulous or scabrous at least upwards, never completely smooth and shining; palea usually well developed." 100 100 "Spikelets 9–16 mm long; lemma lanceolate to narrow-lanceolate to oblong, obtuse, very compressed and keeled, awnless or with a minute dorsal awn behind the tip; panicles spicate, narrow-oblong to cylindrical, tapering upwards, dense, pale; coarse perennial on coastal sand dunes forming dense tussocks with stout rhizomes and long leaves." Ammophila 100 "Spikelets less than 9 mm long, or if longer then the lemma either 2-cleft and awned or mucronate from the sinus or entire and awned from near the apex with an awn twice or more the length of the lemma and the lemma linear." 101 101 "Glumes rigidly ciliate on the keel; lemma entire or 2-cleft with the lobes sometimes aristate, and awned or mucronate from the sinus, 5–11-nerved; panicle spicate, sometimes dense." Echinopogon 101 "Glumes smooth or scabrous on the keel but not ciliate; lemma entire or minutely (often 4-) toothed." 102 102 "Lemma lanceolate, or broad-oblong (and then very small), usually more or less hardened at maturity and usually minutely (often 4-) toothed at the apex, minutely or shortly awned or rarely awnless, the awn not twice as long as the lemma." Deyeuxia 102 "Lemma linear or very narrowly linear-lanceolate, entire or minutely notched with a slender dorsal awn twice to several times as long as the lemma." Dichelachne 103 "Lower florets male and with 2-nerved paleas; glumes well developed, half as long to as long as the lemma; panicle loose or loosely contracted; spikelets often brown and/or shining; plants often fragrant; lodicules present." Hierochloe 103 "Lower florets sterile and without paleas; plants fragrant or not fragrant." 104 104 "Upper or both glumes as longer or longer than the florets." 105 104 "Both glumes distinctly shorter than the florets, sometimes minute." 106 105 "Upper glume as long or longer than the florets, the lower about half as long, both thinly membranous; lower sterile lemma awned from high up on the back, the upper lemma with a stouter geniculate awn near the base; panicle spicate, 1–4 cm long; plants fragrant; lodicules absent." Anthoxanthum 105 "Both glumes longer than and concealing the florets; sterile lemmas reduced to small scales adhering closely to the base of the fertile lemma; fertile florets papery and tough, smooth and more or less shining though often thinly hairy; spikelets strongly laterally compressed, the glumes strongly keeled and often winged on the keels; panicle usually spicate, sometimes somewhat interrupted and branching; plants not fragrant." Phalaris 106 "Caryopsis elliptic in outline, strongly laterally compressed; stamens 6 or 3, rarely 1; sterile florets smooth, hairy, or transversely wrinkled, sometimes with appendages at the base; spikelets in contracted or open panicles or racemes." Ehrharta 106 "Caryopsis linear or oblong in outline, very turgid at maturity; stamens 2–6 but usually 4; sterile florets smooth or scabrous but neither hairy (except sometimes with small tufts of hair at the base) nor wrinkled; spikelets in narrow panicles or racemes." 107 107 "Caryopsis linear; stamens 2–6 but usually 4; sterile florets terminating in distinct, often long, awns, elongate, slender, scabrous, either with the callus very hairy or the lemmas with small tufts of hairs at the base, arranged in narrow, sometimes drooping panicles or racemes with capillary branches and pedicels; glumes small, sometimes minute." Microlaena 107 "Caryopsis oblong; stamens 4; sterile florets very obtuse or truncate to acuminate or mucronate but not awned, without tufts of hair at the base and the callus glabrous, arranged alternately on spicate erect racemes (in N.S.W. species) and with short stiff pedicels." Tetrarrhena 108 "Glumes small and hyaline; florets not compressed or keeled; palea 5-nerved, the lemma 7-nerved, both thinly membranous; coarse tufted perennials in or on the margins of moderately fast-flowing rivers." Potamophila 108 "Glumes reduced to a hyaline rim; florets strongly compressed; palea 2- or 3-nerved, the lemma 5-nerved; annual or slender rhizomatous perennials." 109 109 "Sterile lemmas absent, both lemma and palea 1-keeled and ciliate on the keels, the palea 3-nerved, the lemma 5-nerved; slender rhizomatous perennials." Leersia 109 "Two sterile lemmas present below the fertile lemma, keeled, the palea 2-nerved, the lemma 5-nerved; slender to robust, erect annual (in N.S.W.)." Oryza 110 "Lemmas or rachilla joints bearing long silky hairs that envelope the lemma (at least in fertile florets); lemmas awnless or with a straight awn from the tip, often thin; tall grasses with large plume-like panicles." 111 110 "Lemmas and rachilla joints either glabrous or hairy, if hairy the hairs either not enveloping the lemma or, if so, the lemma bearing a geniculate awn; low to moderately tall grasses." 113 111 "Leaves very long and crowded at the base of the culms; spikelets unisexual or bisexual; lemma of female spikelets covered with long hairs." Cortaderia 111 "Leaves distributed along the culms; tall stout 'reeds'; spikelets bisexual." 112 112 "Lemmas hairy; rachilla joints naked." Arundo 112 "Lemmas naked; rachilla joints hairy." Phragmites 113 "Glumes from 60% as long to longer than the lowest floret, sometimes as long as the spikelet and enclosing the florets; lemma awned from the back or from the sinus of a 2-lobed tip with a geniculate or straight awn or mucro (but the awn, when present, terminal and straight in Eriachne), or awnless; leaves never rigid and pungent-pointed." 114 113 "Glumes usually shorter than the lowest floret and with the upper florets distinctly exserted, rarely longer and then usually with firm dull margins like the lemmas or with the lemmas cleft into 9 lobes or awns or the leaves rigid and pungent pointed; lemmas awnless or with a straight or curved awn from the entire or 2-fid apex, or several-awned or -lobed; leaves rigid and pungent-pointed or not." 131 114 "Lemma awned from the back, or awnless (and then usually annuals), the apex entire or notched; ligule membranous." 115 114 "Lemma awned or with a mucro from the sinus of a 2-lobed tip, or awnless (and then usually perennials), or rarely the awn terminal (in Eriachne); ligule reduced to a row of hairs, or if membranous then erosely ciliate on the margins." 124 115 "Spikelets mostly 4–10-flowered; panicles loose or loosely contracted; spikelets about 1 cm or more long, scarcely compressed; lemma with a rather long geniculate awn from the back; aquatic or semi-aquatic grasses." Amphibromus 115 "Spikelets 2- or 3-flowered, or if up to 6-flowered then the awn short and straight; non-aquatic species." 116 116 "Florets 2 (or 3), 1 bisexual, the other male." 117 116 "Florets (or at least the lower pair) alike and bisexual." 118 117 "Lowest floret usually male and bearing a geniculate awn, the second bisexual and awnless, falling together at maturity." Arrhenatherum 117 "Lowest floret bisexual and awnless, the upper male with a short awn near the tip, the spikelets falling entire at maturity, compressed." Holcus 118 "Spikelets 1 cm or more in length, nodding; florets 2 or 3, the lower 1 or 2 usually awned from the back with a long geniculate awn; glumes closely 7–11-nerved; annuals." Avena 118 "Spikelets less than 1 cm long, erect." 119 119 "Spikelets strictly 2-flowered, with the florets subequal, very small." 120 119 "Spikelets 3–6-flowered or rarely with the third floret reduced and rudimentary." 121 120 "Glumes longer than the usually awned florets." Aira 120 "Glumes shorter than the awnless florets." Periballia 121 "Annuals with terminal or subterminal awns." Rostraria 121 "Perennials with dorsal awns or awnless." 122 122 "Panicles spreading; awns straight, from near the base of the lemma, mostly included within the glumes." Deschampsia 122 "Panicles dense and spicate; awns dorsal or awnless." 123 123 "Lemmas with a dorsal geniculate awn shortly exserted from the glumes." Trisetum 123 "Lemmas awnless or shortly mucronate." Koeleria 124 "Low tufted annuals with more or less thin soft leaves." 125 124 "Perennials (sometimes annuals) with more or less firm, wiry or hard leaves." 126 125 "Spikelets 2-flowered with the rachilla shortly produced; lemma thin, narrowed upwards into short, delicate lateral awns and with a longer, fine, geniculate central awn slightly twisted; leaf blades flat." Pentaschistis 125 "Spikelets about 5-flowered; lemma broad, rounded on the back, distinctly 5–9-nerved, with hyaline margins upwards, shortly 2-lobed with a mucro on the lowest lemma and a minute mucro on the upper lemmas between the lobes; leaf blades flat or rolled." Schismus 126 "Spikelets 2-flowered (rarely 1-flowered); lemma not lobed at the apex, awnless or tapering into a mucro or straight or curved (not twisted) awn." Eriachne 126 "Spikelets 2–several-flowered; lemma more or less 3-lobed, or 2-lobed or 2-cleft and with a mucro or awn from the sinus." 127 127 "Lower leaf sheaths woolly and swollen; drier areas of the State." Monachather 127 "Lower leaf sheaths not woolly and swollen." 128 128 "Awns less than 4 mm long, often reduced to a mucro or lemmas awnless and 3-lobed." 129 128 "Lemma deeply to shortly cleft, the lateral segments often tapering into short awns or points, the central awn more than 4 mm long, geniculate and more or less strongly twisted below the bend." 130 129 "Awn less than 4 mm long, often reduced to a mucro." Plinthanthesis 129 "Lemmas 3-lobed, awnless; low-growing alpine grasses." Rytidosperma 130 "Hilum more or less 30% as long as the grain, situated in a longitudinal groove; hairs of even length scattered over the back of the lemma." Chionochloa 130 "Hilum less than 30% as long as the grain, grain concave; hairs of the lemma arranged variously but usually of different lengths." Danthonia 131 "Lemmas cleft into 9 (in Australian species) subulate or lanceolate or awned lobes." Enneapogon 131 "Lemmas entire or up to 5-lobed or 5-awned." 132 132 "Inflorescence spicate with spikelets on opposite sides of the rachis of solitary spikes or spicate racemes; lemmas awnless or with a terminal awn." 133 132 "Spikelets borne in open or contracted spicate panicles; if arranged on opposite sides of the rachis then the lemmas awned or mucronate from a 2-fid apex." 144 133 "Lemmas usually 1–3-nerved; spikelets 1- or 2-flowered, more or less sunken in hollows or depressions in the articulate rachis, more or less enclosed by the glumes." 134 133 "Lemmas 5–9-nerved; spikelets 1–many-flowered, sometimes more or less sunken in depressions in the rachis but then 3- or more than 3-flowered." 136 134 "Glume 1, thin, very much shorter than the floret; lemma thinly hardened, shortly awned, 3-nerved; spikelets distant on the very slender rachis." Psilurus 134 "Glumes 1 or 2, leathery, longer than the floret; lemma awnless; spikelets rather closely spaced on the rachis." 135 135 "Lower glume very small or suppressed in the lateral spikelets, the upper glume broad and facing the rachis; lemmas of the first (and often only) floret with its back adjacent to the rachis of the spike." Hainardia 135 "Both glumes well developed in the lateral spikelets, placed side by side in front of the cavity in the rachis; lemma with 1 side adjacent to the rachis of the spike." Parapholis 136 "Lower (inner) glume absent on lateral spikelets; spikelets placed with the backs of alternate lemmas to the rachis." Lolium 136 "Both glumes developed; spikelets placed with either the backs of alternate lemmas or with 1 side of all the lemmas to the rachis." 137 137 "Spikelets 1-flowered, in clusters of 3 at each node of the rachis, the 3 falling together." Hordeum 137 "Spikelets solitary at each node of the rachis." 138 138 "Spikelets usually with 2 florets, the rachilla often produced above them; glumes narrow, rigid, acuminate or subulate pointed, 1-nerved; lemmas ciliate on the keels, awned." Secale 138 "Spikelets with more than 2 florets." 139 139 "Glumes very broad, mucronate or toothed or awned, bulging on the back, sometimes keeled above; spikelets 2–5-flowered, placed with 1 side of each of the lemmas against the rachis; lemmas abruptly pointed or awned." Triticum 139 "Glumes not bulging on the back, narrow to moderately broad; spikelets usually more than 5-flowered; lemmas tapering into an awn or awnless." 140 140 "Lemmas awned, the awn more than 50% the length of the lemma." 141 140 "Lemmas awnless or with an awn or mucro less than 50% the length of the lemma." 142 141 "Spikelets shortly pedicellate; awns straight; leaf auricles absent; plants annual." Brachypodium 141 "Spikelets sessile; awns often curving away from the lemmas; leaf auricles usually present; plants perennial." Elymus 142 "Plants strongly rhizomatous; lemmas awnless but may be sharply pointed." Elytrigia 142 "Plants without long rhizomes; lemmas more or less awned." 143 143 "Rachis of inflorescence 1.5 mm or more wide, glabrous but scabrous or ciliate on the edges; glumes more than 2 mm wide, obtuse." Thinopyrum 143 "Rachis of inflorescence 1 mm or less wide, pubescent; glumes 1.2 mm or less wide, acute." Australopyrum 144 "Lemmas usually 5–many-nerved, the nerves never in 3 distinct groups or with the leaves rigid and needle-pointed; plants with non-Kranz anatomy." 145 144 "Lemmas 1–3-nerved or the nerves in 3 distinct groups and then the leaves rigid and needle-pointed; plants all with Kranz anatomy." 159 145 "Spikelets dimorphic, the fertile and sterile intermixed on the same inflorescence." 146 145 "Spikelets all alike on the same inflorescence." 147 146 "Fertile spikelets with 1 bisexual floret, long-awned; sterile spikelets with many obtuse sterile lemmas; small annual with rather dense, somewhat 1-sided, oblong yellowish panicles with crowded groups of spikelets on short drooping branches." Lamarckia 146 "Fertile spikelets 2- or 3-flowered; sterile spikelets with numerous, rigid, awn-tipped lemmas; spikelets borne on 1 side of the main axis of a spicate panicle; annuals or perennials." Cynosurus 147 "Spikelets crowded in 1-sided clusters at the ends of a few, stiffly spreading, naked panicle branches, strongly laterally compressed." Dactylis 147 "Spikelets borne in loose or contracted panicles." 148 148 "Lemmas as broad as long, cordate at the base with outspread margins, closely overlapping, awnless; panicles loose, spreading or nodding." Briza 148 "Lemmas longer than broad and/or not cordate at the base." 149 149 "Lemmas laterally compressed and keeled (only slightly so in some species) and often with web-like hairs on the callus; spikelets small, less than 10 cm long; panicles usually loose and spreading at maturity, more rarely somewhat contracted; lodicules free, membranous." 150 149 "Lemmas rounded on the back at least in the lower part, sometimes slightly keeled upwards or spikelets large and more than 10 mm long." 151 150 "Plants usually less than 1.5 m high; ovary glabrous at apex; hilum punctiform, basal." Poa 150 "Plants often more than 1.5 m high; ovary hairy at the apex; hilum linear-elongate." Dryopoa 151 "Spikelets shortly but distinctly 3-toothed, the teeth equal or the central 1 mucronate; spikelets about 1.5 cm long, solitary or up to 3 on long capillary branches of a somewhat contracted panicle; lemma prominently nerved." Notochloë 151 "Spikelets obtuse or acute or notched but not obviously 3-toothed." 152 152 "Nerves of the lemma converging and the lemma narrowed towards the apex." 153 152 "Nerves of the lemma parallel, not or scarcely converging at the summit, awnless." 157 153 "Ovary with a hairy terminal appendage, the styles arising laterally below it; grain compressed; lemmas usually awned from the minutely notched tip or just behind it." Bromus 153 "Ovary without a hairy terminal appendage, the styles terminal though sometimes inserted rather far apart on the flat top of the ovary." 154 154 "Perennials; lemmas awned from the entire tip or mucronate or awnless; panicles usually spreading with slender branches." 155 154 Annuals. 156 155 "Lemmas rounded on the back; hilum elongated." Festuca 155 "Lemmas keeled throughout; hilum short, oval." Austrofestuca 156 "Lemmas subulate, tapering into a long awn; glumes very unequal; spikelets few on the usually erect, short, slender branches of a contracted panicle." Vulpia 156 "Lemmas awnless, rather obtuse, 2–2.5 mm long; glumes only slightly unequal; panicle 1-sided, stiff, shortly branched below, the spikelets on short thick pedicels." Catapodium 157 "Spikelets shortly pedicellate on short dense racemes that may be overtopped by the leaves." Sclerochloa 157 "Spikelets in open or contracted panicles." 158 158 "Nerves prominent; plants usually rather tall, usually aquatic or semi-aquatic; margins of sheaths fused at least below; lodicules firm, short, truncate, often fused; hilum linear, as long as the grain." Glyceria 158 "Nerves indistinct; plants rather low, usually in saline or alkaline soils or marshes; margins of sheaths free." Puccinellia 159 "Spikelets more or less densely arranged and very shortly pedicellate on a solitary terminal spike; lemmas awned or mucronate from a 2-lobed apex." Tripogon 159 "Spikelets variously arranged in open or contracted or spicate or interrupted panicles but not in simple spikes." 160 160 "Lemmas entire, awnless and not produced into awn-like points." 161 160 "Lemmas distinctly or obscurely notched and then often with a small mucro from the sinus, or awned, or at least truncate and more or less erose and then the spikelets racemose on elongate panicle branches." 163 161 "Plants dioecious; perennials with creeping rhizomes; usually on saline soils." Distichlis 161 "Plants monoecious; perennials or annuals, usually without creeping rhizomes; habitats various." 162 162 "Lemmas 1-nerved, thinly membranous; spikelets borne on the branches of a dense spicate panicle, 2- or 3-flowered." Thellungia 162 "Lemmas 3-nerved, various in texture; spikelets in open or contracted panicles, rarely in racemes or few together in spicate clusters or short branches." Eragrostis 163 "Blades hard, stiff, often pungent-pointed, flat or more commonly permanently folded (and then sometimes appearing needle-like); lemmas more or less distinctly 2-toothed or lobed, or emarginate." Triodia 163 "Leaf blades soft or rigid, neither very hard nor pungent-pointed; lemmas various but not 3-lobed or toothed." 164 164 "Spikelets racemose on elongate branches of the panicle, lemmas truncate and more or less erose or notched and sometimes mucronate but not or scarcely awned." 165 164 "Spikelets in dense, spicate, sometimes interrupted panicles on their spicate branches; lemmas short- or long-awned or tapering into awn-like points." 166 165 "Lemmas truncate and/or erose or minutely notched, not or scarcely mucronate, lateral nerves often shortly hairy." Leptochloa 165 "Lemmas rather distinctly notched and mucronate, fringed with hairs in the lower part." Diplachne 166 "Lemmas 3-awned and toothed on either side of the central awn." Triraphis 166 "Lemmas with a single awn or awn-like point" Elytrophorus