=Molluginaceæ=
ll) Petals contorted:
=Linaceæ=
jj) Flowers unisexual; disk present or obscure.
=Euphorbiaceæ=
=GROUP 11. One carpel or more than one united carpels; ovules attached
to the central axis or to the base or apex of the ovary cell; ovary
superior; petals present, more or less united.=
a) Stamens the same number as and opposite to the corolla lobes:
b) Ovules solitary in the whole ovary or in each cell of the ovary;
style often lobed:
c) Trees or shrubs, often with hard wood:
d) Petals imbricate; hairs often stellate or medifixed; staminodes
often present, sometimes petaloid.
=Sapotaceæ=
dd) Petals valvate; hairs usually simple; usually no staminodes:
e) Inflorescence not leaf-opposed; leaves simple, without tendrils.
=Olacaceæ=
ee) Inflorescence leaf-opposed; leaves often compound; mostly
climbers with tendrils.
=Ampelidaceæ=
cc) Herbs or climbers:
d) Corolla lobes valvate; tendrils often present; inflorescence
usually cymose-paniculate, leaf-opposed; leaves usually with the
stipules adnate to the petiole; petals united at the base.
=Ampelidaceæ=
dd) Corolla lobes imbricate; no tendrils; inflorescence more or less
corymbose; petals united high up.
=Plumbaginaceæ=
bb) Ovules 2 or more in each cell; style undivided; placentas basal:
c) Trees or shrubs often with gland-dotted simple leaves; leaves
exstipulate.
=Myrsinaceæ=
cc) Herbs or climbers usually with compound stipulate leaves and
leaf-opposed inflorescence.
=Ampelidaceæ=
ccc) Herbs with opposite simple leaves and solitary or axillary
scarlet, blue or rose flowers; leaves not gland-dotted, exstipulate.
=Primulaceæ=
aa) Stamens the same number as the corolla-lobes and alternate with
them, or more numerous or fewer:
b) Stamens more than twice as many as the corolla lobes; flowers
unisexual; corolla lobes about 5; leaves stipulate.
=Euphorbiaceæ=
bb) Stamens as many as or up to twice as many as the corolla lobes or
fewer:
c) Stamens as many as or more numerous than the corolla lobes:
d) Flowers zygomorphic (irregular):
e) Petals united only at the base; seeds often pilose; ovules
pendulous.
=Polygalaceæ=
ee) Petals united high up into a tube:
f) Ovules numerous in each cell; herbs; corolla lobes 5.
=Solanaceæ=
ff) Ovules solitary in each complete or incomplete cell; habit
various; corolla lobes 4.
=Verbenaceæ=
dd) Flowers actinomorphic (regular):
e) Leaves opposite or verticillate, mostly exstipulate:
f) Anthers opening by apical pores or pore-like slits:
g) Leaves in whorls; woody shrubs or undershrubs with usually
very small leaves; stamens hypogynous.
=Ericaceæ=
gg) Leaves paired; herbs; stamens epipetalous.
=Gentianaceæ=
ff) Anthers opening by longitudinal slits:
g) Style single with often a large more or less capitate stigma:
h) Corona present in the flowers; mostly herbs or weak twiners,
often with milky juice.
=Asclepiadaceæ=
hh) Corona absent:
i) Leaves exstipulate:
j) Trees, shrubs or climbers often with milky juice; corolla
lobes contorted-imbricate or rarely valvate.
=Apocynaceæ=
jj) Herbs; corolla lobes imbricate; disk present.
=Scrophulariaceæ=
jjj) Herbs with spicate flowers and radical leaves; corolla
lobes imbricate; no disk.
=Plantaginaceæ=
ii) Leaves stipulate or sheathing at the base.
=Loganiaceæ=
gg) Styles with more than 1 separate stigma:
h) Stamens double the number of the corolla lobes; flowers
dioecious; endosperm copious, hard.
=Ebenaceæ=
hh) Stamens the same number as the corolla lobes:
i) Rudimentary stipules often present; stamens and corolla
lobes 4.
=Salvadoraceæ=
ii) Stipules absent:
j) Style gynobasic:
=Boraginaceæ=
jj) Style terminal:
k) Trees or shrubs:
l) Ovules numerous in each cell or, if solitary, then
corolla lobes valvate.
=Loganiaceæ=
ll) Ovules 1-2 in each cell; corolla lobes imbricate.
=Verbenaceæ=
kk) Herbs or herbaceous climbers:
l) Ovary imperfectly celled by the intrusive placentas.
=Gentianaceæ=
ll) Ovary perfectly 2-celled with axile placentas; style
simple.
=Solanaceæ=
ee) Leaves alternate or all radical or reduced to scales:
f) Leafless parasites destitute of chlorophyll; ovary 2-celled;
ovules 2 in each cell.
=Convolvulaceæ=
ff) Not parasitic or rarely so and then leafy:
g) Leaves densely covered with viscid gland-tipped tentacles,
mostly all radical; more or less stemless herbs.
=Droseraceæ=
gg) Leaves without tentacles:
h) Leaves stipulate:
i) Flowers unisexual; petals not bifid.
=Euphorbiaceæ=
ii) Flowers hermaphrodite; petals bifid.
=Chailletiaceæ=
hh) Leaves without stipules:
i) Stamens hypogynous or perigynous, free from the corolla or
slightly adnate to its base:
j) Anthers opening by terminal pores, often with appendages;
woody plants.
=Ericaceæ=
jj) Anthers opening by longitudinal slits:
k) Stamens 4-6:
l) Leaves gland-dotted; petals connivent by their claws;
disk usually conspicuous.
=Rutaceæ=
ll) Leaves not gland-dotted.
m) Petals only slightly united at the base:
n) Leaves pinnate or 1-3-foliolate.
=Connaraceæ=
nn) Leaves simple:
o) Stamens opposite the petals.
=Olacaceæ=
oo) Stamens alternate with the petals.
=Pittosporaceæ=
mm) Petals united high up, sometimes free at the base:
n) Trees or shrubs.
=Burseraceæ=
nn) Herbs.
=Campanulaceæ=
kk) Stamens more than 6:
l) Corolla tube fairly long; no disk; leaves not very small.
=Ebenaceæ=
ll) Corolla tube very short; disk present; leaves very
small.
=Tamaricaceæ=
ii) Stamens inserted on or adnate to the corolla tube:
j) Style gynobasic:
k) Style 1; fruit composed of pyrenes or nutlets; corolla
imbricate or contorted.
=Boraginaceæ=
kk) Styles 2; fruit a capsule; corolla plicate.
=Convolvulaceæ=
jj) Style not gynobasic, terminal:
k) Corolla valvate or plaited in bud (in the latter case the
limb may be somewhat twisted but not truly imbricate):
l) Ovules 1-4 in each ovary cell; stamens inserted towards
the base of the corolla tube.
=Convolvulaceæ=
ll) Ovules numerous (rarely 3-6) in each ovary cell.
=Solanaceæ=
kk) Corolla imbricate:
l) Herbs with radical leaves and flowers in slender spikes.
=Plantaginaceæ=
ll) Herbs, trees or shrubs; flowers not in slender spikes:
m) Ovules 1 in each cell; trees and shrubs.
=Boraginaceæ=
mm) Ovules numerous in each cell; herbs or small shrubs.
=Solanaceæ=
cc) Stamens fewer than the corolla lobes; leaves mostly opposite:
d) Flowers actinomorphic:
e) Stamen 1; climbers or shrubs; seeds winged; one calyx lobe much
larger than the others and petaloid.
=Loganiaceæ=
ee) Stamens more than 1:
f) Stamens 6-8 opposite the inner lobes of the corolla; ovules
solitary in each cell; trees or shrubs.
=Sapotaceæ=
ff) Stamens alternate with the corolla lobes:
g) Peduncle of the inflorescence adnate to the petiole; corolla
lobes or some of them 2-cleft.
=Chailletiaceæ=
gg) Peduncle not adnate to the petiole; corolla lobes not cleft
or only slightly so:
h) Ovules few (1-4) in each cell of the ovary:
i) Disk none; stamens 2; shrubs, trees or climbers; leaves
simple or pinnate.
=Olacaceæ=
ii) Disk present; stamens usually 4; shrubs or trees; leaves
simple or digitate.
=Verbenaceæ=
hh) Ovules numerous:
i) Corolla lobes minute, valvate, alternating with entire or
2-lobed appendages.
=Solanaceæ=
ii) Corolla lobes imbricate, without appendages.
=Scrophulariaceæ=
dd) Flowers zygomorphic:
e) Aquatic herbs with bladder-like leaves; stamens 2; anthers
1-celled; sepals 2; ovules on a free basal placenta.
=Lentibulariaceæ=
ee) Characters not as above:
f) Ovary not deeply lobed; style not gynobasic:
g) Ovules numerous in the whole ovary or in each cell of the
ovary, or if 2 then superposed:
h) Leaves pinnately compound; ovules numerous; seeds often
winged, without endosperm; shrubs or trees.
=Bignoniaceæ=
hh) Leaves simple; mostly herbaceous:
i) Ovules numerous; ovary 2-celled; seeds usually minute.
=Scrophulariaceæ=
ii) Ovules 1 to many; ovary 2-4 celled; seeds not on hook-like
funicles.
=Pedaliaceæ=
iii) Ovules few; ovary 2-celled; leaves rarely all radical;
seeds on hook-like funicles.
=Acanthaceæ=
gg) Ovule solitary in each cell of the ovary or if 2 then
collateral; herbs, shrubs or trees.
=Verbenaceæ=
ff) Ovary deeply 4-lobed; style gynobasic; leaves opposite or
verticillate; flowers often in whorls; stems usually quadrangular.
=Labiatæ=
=GROUP 12. One carpel or more than one united carpels; ovules attached
to the central axis or to the base or apex of the ovary cell; ovary
superior; petals absent.=
a) Calyx absent from the hermaphrodite and often from the female
flowers:
b) Moss-like or hepaticiform aquatic herbs with minute flowers; ovules
2 or more in a 1-celled ovary.
=Podostemonaceæ=
bb) Above characters not associated:
c) Flowers surrounded by an involucre margined by fleshy glands; male
flowers several to numerous and each consisting of a single stamen,
with a single female flower often stalked in their midst.
=Euphorbiaceæ=
cc) Flowers not as above:
d) Leaves stipulate, stipules sometimes adnate to the petiole:
e) Herbs or shrubs; flowers in dense spikes; petioles not dilated
and not enclosing the young bud.
=Piperaceæ=
ee) Trees or shrubs; flowers on a common open receptacle, the fruit
becoming immersed in it.
=Moraceæ=
dd) Leaves without stipules; herbs sometimes slightly woody at the
base; ovary 1-celled.
=Urticaceæ=
aa) Calyx always present:
b) Moss-like or hepaticiform aquatic herbs with minute flowers; ovules
2 or more in a 1-celled ovary.
=Podostemonaceæ=
bb) Above characters not associated:
c) Leaves opposite or verticillate, never all radical:
d) Leaves stipulate:
e) Flowers hermaphrodite:
f) Herbs, sometimes slightly woody at the base; leaves mostly
pinnate.
=Zygophyllaceæ=
ff) Herbs with simple leaves.
=Illecebraceæ=
fff) Trees or shrubs with reduced flowers; leaves simple.
=Ulmaceæ=
ee) Flowers unisexual:
f) Ovary 2- or more-celled, often deeply lobed; seeds usually with
a distinct caruncle.
=Euphorbiaceæ=
ff) Ovary 1-celled; ovary usually not lobed:
g) Ovule erect:
h) Filaments inflexed; mostly herbaceous with fibrous stems;
juice not milky.
=Urticaceæ=
hh) Filaments not inflexed; mostly trees and shrubs, rarely
herbs; juice mostly milky, the flowers often minute and arranged
on or inside an enlarged receptacle.
=Moraceæ=
gg) Ovule pendulous:
h) Not aquatic:
i) Filaments not inflexed in bud:
j) Fruit a drupe; flowers monœcious or subdiœcious.
=Ulmaceæ=
jj) Fruit a small dry achene; flowers diœcious.
=Cannabinaceæ=
ii) Filaments erect or inflexed in bud.
=Moraceæ=
hh) Aquatic herb with verticillate divided leaves.
=Ceratophyllaceæ=
dd) Leaves exstipulate:
e) Flowers unisexual; ovary usually 2- or more celled; seeds
usually with a distinct caruncle.
=Euphorbiaceæ=
ee) Flowers hermaphrodite; ovary 1-celled:
f) Stamens involute in bud; calyx more or less herbaceous, often
long and tubular, mostly covered with sticky glands.
=Nyctaginaceæ=
ff) Stamens erect in bud:
g) Sepals free or nearly so, calyx more or less dry and scarious:
=Amarantaceæ=
gg) Sepals more or less united, herbaceous.
=Ficoidaceæ=
cc) Leaves alternate or radical or reduced to scales:
d) Leaves stipulate:
e) Stamens monadelphous, usually numerous; calyx valvate:
f) Flowers usually hermaphrodite; hairs usually stellate.
=Sterculiaceæ=
ff) Flowers always unisexual; hairs often simple.
=Euphorbiaceæ=
ee) Stamens free or shortly connate only at the base:
f) Stamens the same number as the sepals and alternate with them.
=Rhamnaceæ=
ff) Stamens the same number as the sepals and opposite to them, or
more numerous or fewer:
g) Stipules ochreate, _i.e._, sheathing and more or less
membranous around the stem; fruit a small nut.
=Polygonaceæ=
gg) Stipules not ochreate:
h) Flowers hermaphrodite; stipules sheathing, sometimes adnate
to the petiole:
i) Leaves digitately lobed; stems herbaceous creeping.
=Rosaceæ=
ii) Leaves not digitate; erect or diffuse herbs.
=Molluginaceæ=
hh) Flowers unisexual; stems not creeping:
i) Ovary 3-celled, composed of 3 carpels; fruit a capsule.
=Euphorbiaceæ=
ii) Ovary 1-celled, composed of 1 carpel, fruit not a capsule.
=Moraceæ=
dd) Leaves exstipulate:
e) Leaves ternately compound; herbs; ovary composed of 1 carpel,
long-stipitate in fruit; flowers paniculate or racemose, very
small.
=Ranunculaceæ=
ee) Leaves compound; trees and shrubs:
f) Cultivated trees with milky latex; fruit a capsule, with
pendulous seeds; flowers unisexual; leaves digitate.
=Euphorbiaceæ=
ff) Indigenous trees or shrub; latex not milky; leaves pinnate.
=Sapindaceæ=
eee) Leaves simple:
f) Stamens circinnately involute in bud; calyx tube often rather
long; ovary 1-celled; ovule 1, basal.
=Nyctaginaceæ=
ff) Stamens sometimes inflexed but not circinnate in bud:
g) Stamens more or less connate into a central column; ovule
erect; seeds with ruminate endosperm.
=Myristicaceæ=
gg) Stamens free or the filaments shortly connate only at the
base:
h) Stamens distinctly perigynous; sepals connate into a tube
below:
i) Twiners; flowers in axillary spikes, racemes or panicles;
ovule solitary, basal.
=Basellaceæ=
ii) Herbs; stamens numerous; flowers solitary or clustered in
the axils of the leaves.
=Ficoidaceæ=
iii) Trees or shrubs; calyx mostly long and petaloid; leaves
frequently small and evergreen; stamens definite; anthers
opening by slits.
=Thymelæaceæ=
hh) Stamens hypogynous or slightly perigynous if accompanied by
a disk:
i) Flowers arranged in an involucre (cyathium) margined by
glands; male flower reduced to a single stamen, the female to a
single stipitate ovary.
=Euphorbiaceæ=
ii) Flowers not as above; stamens more than 1:
j) Trees or shrubs:
k) Flowers unisexual; ovules solitary, pendulous; seed with
straight embryo.
=Euphorbiaceæ=
kk) Flowers unisexual or polygamous; ovules 2 in each cell,
collateral or the lower ascending; embryo spirally twisted.
=Sapindaceæ=
jj) Herbs:
k) Calyx scarious; flowers often in spikes or heads; ovule 1
in a 1-celled ovary.
=Amarantaceæ=
kk) Calyx herbaceous; flowers more or less paniculate; ovule
1 in a 1-celled ovary.
=Chenopodiaceæ=
=GROUP 13. One carpel or more than one united carpels; ovules attached
to the central axis or to the base or apex of the ovary cell; ovary
inferior; petals present, free from each other.=
a) Leaves opposite or verticillate; never all radical; rarely reduced
to scales:
b) Leaves stipulate:
c) Stamens opposite the petals and the same number.
=Rhamnaceæ=
cc) Stamens alternate with the petals or more numerous:
d) Ovary composed of 2-6 carpels; 2-6 celled; flowers rarely
congested; ovules pendulous; mostly maritime trees or shrubs.
=Rhizophoraceæ=
dd) Ovary various; flowers rarely in heads; ovules ascending or
attached to the central axis; trees, shrubs or herbs.
=Rosaceæ=
bb) Leaves exstipulate:
c) Trees, shrubs or climbers:
d) Stamens numerous; leaves gland-dotted; style simple with a small
capitate stigma or rarely 3-4 lobed.
=Myrtaceæ=
dd) Stamens as many to twice as many as the petals:
e) Stamens the same number and opposite the petals; mostly
parasitic shrubs or trees; calyx usually much reduced.
=Loranthaceæ=
ee) Stamens the same number and alternate with the petals or more
numerous:
f) Anthers opening by a terminal pore; filaments often jointed;
leaves often with 3-9 longitudinally parallel nerves.
=Melastomataceæ=
ff) Anthers opening by longitudinal slits; calyx mostly valvate;
ovules 2 or more; fruits mostly winged; endosperm absent; flowers
in heads, spikes, racemes or panicles.
=Combretaceæ=
cc) Herbs:
d) Anthers opening by a terminal pore; leaves mostly with
longitudinally parallel nerves; filaments often jointed.
=Melastomataceæ=
dd) Anthers opening by longitudinal slits:
e) Ovules numerous on placentas pendulous from the apex of the
1-celled ovary.
=Saxifragaceæ=
ee) Ovules 1-4, pendulous from the top of the ovary cells.
=Halorrhagaceæ=
aa) Leaves alternate or all radical:
b) Flowers unisexual:
c) Flowers mostly zygomorphic; stamens mostly indefinite in number;
no tendrils; stipules paired.
=Begoniaceæ=
cc) Flowers actinomorphic; stamens definite or rarely many, usually
3; anthers often curved or twisted; tendrils present or absent; no
stipules.
=Cucurbitaceæ=
bb) Flowers hermaphrodite:
c) Leaves stipulate:
d) Herbs; leaves usually compound or much dissected, sometimes
peltate; sepals very small; fruit composed of 2 indehiscent
mericarps.
=Umbelliferæ=
dd) Trees or shrubs:
e) Stamens the same number and opposite the petals; leaves entire
or toothed.
=Rhamnaceæ=
ee) Stamens alternate with the petals or more numerous or fewer;
flowers mostly in umbels; leaves compound, rarely simple; fruit a
berry or drupe.
=Araliaceæ=
cc) Leaves exstipulate:
d) Stamens as many as and opposite to the petals; often parasitic on
other trees and shrubs; corolla usually brightly coloured.
=Loranthaceæ=
dd) Stamens alternate with the petals or more numerous; not
parasitic:
e) Herbs:
f) Ovules more than 1 in each ovary cell; ovary mostly 4-celled.
=Onagraceæ=
ff) Ovules 4 in a 1-celled ovary; flowers monœcious or polygamous,
not umbellate.
=Halorrhagaceæ=
fff) Ovules solitary in each cell; usually pendulous; flowers
umbellate; carpels separating in fruit into 2 indehiscent
mericarps.
=Umbelliferæ=
ee) Shrubs or trees:
f) Petals entire or at most toothed; ovary 1-celled.
=Combretaceæ=
ff) Petals entire, 2-lobed or laciniate, often involute; ovary
4-celled.
=Rhizophoraceæ=
=GROUP 14. One carpel or more than one united carpel; ovules attached to
the central axis or to the base or apex of the ovary cell; ovary
inferior; petals present, more or less united.=
a) Leave opposite:
b) Leaves stipulate, entire, stipules mostly inter- or intrapetiolar;
anthers free from each other; corolla always actinomorphic.
=Rubiaceæ=
bb) Leaves exstipulate:
c) Anthers free from each other; ovules mostly pendulous:
d) Leaves not gland-dotted; stamens definite; shrubs, mostly
parasitic on trees; flowers usually not in heads and not surrounded
by bracts.
=Loranthaceæ=
dd) Leaves gland-dotted; stamens mostly numerous; trees or shrubs;
flowers cymose or fasciculate.
=Myrtaceæ=
cc) Anthers mostly connivent or in pairs around the style:
d) Ovule solitary erect; flowers mostly in heads surrounded by an
involucre of bracts.
=Compositæ=
dd) Ovules numerous; flowers usually not in heads and not surrounded
by bracts.
=Campanulaceæ=
aa) Leaves alternate or radical:
b) Anthers free from one another:
c) Stamens the same number and opposite the corolla lobes:
d) Herbaceous, leaves not gland-dotted.
=Primulaceæ=
dd) Trees and shrubs:
e) Not parasitic; leaves often gland-dotted; corolla short.
=Myrsinaceæ=
ee) Often parasitic; leaves not gland-dotted; corolla often long.
=Loranthaceæ=
cc) Stamens alternate with the corolla lobes or more numerous or
fewer:
d) Flowers hermaphrodite; stems not climbing; anthers straight.
=Campanulaceæ=
dd) Flowers unisexual; stems often climbing by tendrils; anthers
often sinuous or twisted.
=Cucurbitaceæ=
bb) Anthers united into a ring around the style or flowers unisexual:
c) Flowers not in heads surrounded by a common involucre.
=Lobeliaceæ=
cc) Flowers in heads surrounded by a common involucre.
=Compositæ=
=GROUP 15. One carpel or more than one united carpels; ovules attached
to the central axis or to the base or apex of the ovary cell; ovary
inferior; petals absent.=
a) Parasitic herbs destitute of chlorophyll, the leaves reduced to
scales; ovules nude or with a single integument:
b) Flowers densely crowded; fruits nut-like, 1-seeded; ovule solitary,
pendulous.
=Balanophoraceæ=
bb) Flowers solitary, large; ovules numerous.
=Hydnoraceæ=
aa) Not parasitic or if so then more or less woody and often with
normally developed leaves:
b) Leaves stipulate:
c) Flowers unisexual, stamens and ovules few, the latter solitary;
trees or shrubs.
=Moraceæ=
cc) Flowers hermaphrodite; stamens the same number and alternate with
the sepals.
=Rhamnaceæ=
bb) Leaves exstipulate:
c) Ovules pendulous from the apex of the ovary or from the apex of a
basal placenta:
d) Not parasitic; stamens inflexed in bud, often double the number
of the sepals; fruits often winged.
=Combretaceæ=
dd) Mostly parasitic; flowers small and leaves often reduced;
stamens erect in bud, the same number and opposite the sepals; fruit
not winged.
=Santalaceæ=
cc) Ovule 1, erect; mostly parasitic; flowers often brightly
coloured.
=Loranthaceæ=
ARTIFICIAL KEY TO THE FAMILIES OF MONOCOTYLEDONES REPRESENTED IN THIS
FLORA.
a) Flowers very small, arranged on a spadix, more or less enclosed by a
green or coloured spathe; erect, creeping or climbing herbs; rootstock
often tuberous or thick and fleshy.
=Araceæ=
aa) Flowers not arranged as above:
b) Small or minute floating plants not differentiated into stem and
leaves and with much reduced flowers consisting of 1-2 stamens and a
sessile ovary either naked or enclosed in a membranous perianth,
anthers 1-2 celled; ovary 1-celled; ovule 1 or more on a basal
placenta.
=Lemnaceæ=
bb) Characters not as above; if aquatic plants then usually with well-
developed leaves:
c) Ovary apocarpous, of more than 1 carpel:
d) Submerged aquatic plants:
e) Perianth-segments 1-3, white or coloured.
=Aponogetonaceæ=
ee) Perianth-segments 4 and herbaceous, or absent.
=Potamogetonaceæ=
dd) Not aquatic or if so then not submerged:
e) Carpels indehiscent; ovules 1 to few, basal or on the inner
angle of the carpel; marsh or aquatic herbs.
=Alismataceæ=
ee) Carpels dehiscent; ovules numerous on reticulately branched
parietal placentas; scapigerous marsh herbs with milky juice;
stamens usually 9.
=Butomaceæ=
eee) Carpels or fruit indehiscent, trees or shrubs with simple
stems and usually large, often palmate leaves.
=Palmaceæ= (part)
cc) Ovary syncarpous or carpel solitary:
d) Ovary superior:
e) Flowers in the axils of membranous or more or less dry bracts
(glumes) arranged in spikelets mostly arranged in spikes, racemes,
panicles or heads; carpel solitary; perianth of small scales or
bristles or absent:
f) Stems usually triangular, solid and without nodes; leaf-sheaths
mostly closed all round the stem and usually without a ligule;
filament often attached to the base of the anther; ovule basal;
seed free from the pericarp.
=Cyperaceæ=
ff) Stems mostly cylindrical and hollow between the nodes; leaf-
sheaths nearly always split down one side and often terminating in
a distinct ligule; filament usually attached to the back of the
anther; ovule attached laterally; seed more or less adnate to the
pericarp.
=Gramineæ=
ee) Flowers usually with a distinct perianth or at any rate not in
spikelets, etc., as above; ovary usually composed of more than 1
carpel:
f) Flowers mostly hermaphrodite or if unisexual then not collected
into involucrate heads or dense spikes:
g) Ovules on parietal placentas; fertile stamens 3: all the
perianth-segments petaloid; aquatic herbs; stamens 3 or 1.
=Pontederiaceæ= (part)
gg) Ovules on axile or basal placentas; fertile stamens usually
6:
h) Perianth present:
i) Perianth-segments 2-seriate, the outer herbaceous, the inner
petaloid; leaf-bases sheathing.
=Commelinaceæ=
ii) Perianth-segments all more or less petaloid:
j) Aquatic floating herbs with long petioles sheathing at the
base; 3 upper stamens included, 3 lower ones more or less
exserted.
=Pontederiaceæ=
jj) Not aquatic or rarely subaquatic; stamens 6, more or less
equal;
=Liliaceæ=
hh) Perianth absent or very rudimentary; carpel 1; submerged
aquatics with branched filiform smooth or muricate stems,
flowers diœcious or monœcious, axillary, small.
=Naiadaceæ=
ff) Flowers unisexual, collected into involucrate heads or dense
spikes:
g) Flowers in dense involucrate heads; low herbs often stemless
with mostly densely crowded leaves.