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Fio. 406.— ii Flower of Dicentra uptetahilia : one of the outer petals U removed : • pedicel ;
ca ihe outer, ci the inner petals ; /stamenB. B The three stamenB of one side, aeen from
within : /filaments ; a the middle complete anther ; a, a, the lateral half«anthers. C Flower-
bud, wibh the sepals, which soon fall off*, still adhering (k) ; (nat, size). Diagram of Fumi-
tory.

petals is spurred, and consequently the flower is irregular and laterally zygo-
morphio. In Corydalis the fruit is a two-valved capsule with numerous parietal
seeds : some species, e,g, C, cava and solidat have a tuberous rootstock ; others,
as C. lutea and aurea, have rhizomes. Fumaria ojfficinalii and others (Fumi-
tories) are common in fields ; the ovaries contain but few ovules, and of these
only one ripens to a seed ; fruit globose, indehiscent.

Order 3. Cbuciferje. Flowers regular, isobilateral : floral for-
mula K2 + 2, 0x4,^2 + 22, O^K The four petals form a whorl,
alternating with the four sepals as if the latter formed one whorl ;
^ there are, however, three perianth- whorls, as

in the two preceding families ; bnt whereas
in them only the outermost whorl is sepa-
loid, in this family the two outer whorls
are sepaloid, and the innermost, which alone
is petaloid, is a whorl consisting of fonr
instead of two members. The two outer
stamens are lateral, as in those families ; the
two inner ones, which in most Fnmariacc88
are apparently divided, are here duplicate, having longer filaments
(Fig. 407 Bhh) than the outer ones (a) ; hence the flower is tetra-
dynamofcs. There are usually four, sometimes more, glands at the




Fio. 406.— Diagram of the
flower of Gracifene.



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DIC0TYLED0NE8 : POLTPETAL^ : THALAMIFLORfi.



603



base of the stamens (Fig 407 J? d). The ovary consists of two
carpels with the ovnles in two longitudinal rows on the connate
margins of the carpels ; these two parietal placenta are connected
by a membranous growth which, as it is not formed of the margins
of the carpels, mnst be regarded as a spurious dissepiment (Figs.
407 D* E*v, 342 Cw). When the fruit opens, the pericarp splits
into two valves corresponding to the carpels, leaving their mar-
gins, as a frame or repluM, bearing the placentfiB with the spurious
dissepiment attached : the seeds remain attached to them for some
time (Fig. 342 C, p. 530).




F/ G''



1 1 "©■ I



r^^



Fio. 407.— Flowers, fruits, and embryos of various Cruciferse. A Flower of Brassica (nat.
size) ; 8 pedicel ; h k calyx ; c corolla. B The same after removal of the perianth (much
mag.): a a the two outer short stamens ; h the four longer inner ones; /the ovary ; n the
stigma ; d gland. C Siliqua of BrasBica : v dissepiment. 2) Augustiseptal silicula of Thlaspi .
B Latiseptal silicula of Draba. V* and B* Diagrammatic transverse section of the preced-
ing : V dissepiment; s seed. F Indehiscent silicula of Isatis. G Jointed siliqua of Raphanu*
Baphanistrum : g style ; III separate segments. K-U Diagrams of differently-folded
embryos, with transverse sections : r radicles ; c c cotyledons.

The flowers are in racemes in which the bracts are suppressed ;
when the lower pedicels are longer than the upper ones, the raceme
becomes a corymb, and then the lower flowers are usually zygomor-
phic, the petals turned towards the periphery being larger than
those directed towards the axis of the inflorescence, as in Iberis.

The form of the fruit is of importance in the subdivision of this
order. In some genera it is much longer than it is broad, when it



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604 PART III. — THE CLASSIFICATION OF PLANTS.

is termed a siliqua, (Figs. 407 0, 342 C) ; in others, it is not mnch
longer, or aboat as long as it is broad, when it is termed a siliaila
(Fig. 407 D and J^). The latter is commonly somewhat com-
pressed in one direction ; either parallel to the dissepiment, that is
to say laterally (Fig. 407 E and E*), so that the dissepiment lies
in the direction of the greatest diameter, when it is latiseptal ; or
perpendicularly to the dissepiment, that is in the median plane,
so that the dissepiment lies in the narrowest diameter, when it is
angustiseptal (J) and D*). Fruits with only one or a few seeds, and
which are indehiscent, are confined to only a few genera, such as
Isatis (Fig. 407 F), So likewise is the jointed siliqua, which haa
transverse dissepiments between the seeds ; when they are ripe it
divides transversely into segments, as in Raphanus (^ig. 407 (?).

The seed is exalbuminous. The embryo is folded in the secMi
in various ways ; the radicle may lie in the same plane as one of
flat cotyledons (Fig. 407^, when the cotyledons are said to be
iticumbent, Notorhizem (the diagram being O ||) ; or the radicle
may occupy the same position, the cotyledons being folded (Fig.
407 /), when the cotyledons are said to be incumbent and folded^
OrthoploceoB (diagram of section O ^) ; or, thirdly, the radicle may
be lateral to the two cotyledons (Fig. 407 JT), when the cotyledons
are said to be accumbenty Pleurorhize(B (diagram O =) : more
rarely the cotyledons are spirally rolled so that in a transverse
section they are cut through twice, Spirolobece (diagram O || ||) ;
or, finally, they may be doubly folded, and be seen four times in
a section, Dtplocolobeoe (diagram O || || || ||). The seeds contain
much fatty oil.

Sub-order 1. Siliquosjb. Fruit a siliqua, much longer than it is broad.

Tribe 1. Arabidete. Q =. Cheirantkut Cheiri^ the Wall-flower, and Matthiola
annxM and incanat the Stocks, are cultivated as garden-plants. Na$turtitun
officinale is the Water-cress. Barbarea vulgarii is the Tellow Bocket. Carda-
mine (incl. Dentaria) also belongs to this tribe.

Tribe 2. Si$ymbrie<e. Q \\. Si$ymbrium officinale^ the Hedge-Mustard, is
common on rubbish heaps ; ani Erysimum, the Treaole-Mustard, on walls, eie.
Hesperis is the Dame's Violet.

Tribe 8. Bratticea. Q ^' ^he species and varieties of Brassica are much
cultivated. Brassica oUracea is the Cabbage, with the following varieties ;
acephala, Scotch kale, Cow-cabbage or Borecole ; bullata, the Savoy-cabbage ;
capitata, the red and white Cabbage ; catUorapay with the stem swollen at the
base, is the Kohl-rabi ; Botrytts^ with connate fleshy peduncles and abortive
flowers, is the Broccoli (asparagoides) and the Cauliflower {cauUJlora) ; gemmifera^
with numerous lateral leaf -buds, known as Brussels-sprouts. Brauica cam-
pestris is the wild Navew; it includes the following sub-species: Rapa^ the



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DICOTYLEDONES : POLYPETALJE : TitALAMIFLOR-fi. 605

wild Turnip, with bright green hispid leaves and flat corymbs of flowers, among
the cultivated varieties of which is the var. depressa^ the Turnip : Napus^ the
wild Rape, with glabrous glaucous leaves and long racemea of flowers, several
varieties of which are cultivated for their oily seeds, and one (var. esculenta,
the Teltow Turnip) for its fleshy root: Napobrassica, the Turnip-cabbage,
including Butahaga^ the Swedish Turnip. B, campettris oleifera is the true
Colza or Coleseed, from the seeds of which colza-oil is obtained. Bratniea
{Sinapis) nigra and alba are the black and white Mustard. Bras»ica Sinapis
{Sinapit arvensU) is the Charlock or Corn-Mustard. To this tribe belongs also
the genus Diplotazis.

Sub-order 2. SiLicniiOBJB. Fruit a silicula.

A. Latisepta, The dissepiment is in the longest diameter of the silicula.
Tribe 4. Alyninea. Q ■"• Cochlearia ojieinalii is the Scurvy-grass ; C.

Armoraciay the Horse-radish, has a thickened root. Alyssum calycinum and
Draba {Brophila) vernal the Whitlow-grass (Fig. 407 £), are common weeds :
Lunaria biennii is Honesty.

Tribe 5. Camelineie. O ■■ • ^<> ^^^^ tribe belong Camelina(Gk>ld-of- pleasure),
and Subularia, the Awl- wort, an aquatic plant.

B. AngtutUepta. The dissepiment is in the shortest diameter of the silicula.
Tribe 6. Lepidinea, Q R . Capsella Bursa Pastorii^ the Shepherd's Purse,

is common, as also various species of Senebiera and Lepidium (Cresses).

Tribe 7. Thl^ispidea. Q "" * ^&riouB species of Thlaspi, the Penny-Cress,
are common. To this tribe belong also the British genera Iberis (Candytuft),
Tee^dalia, and Hutohinsia.

Sub-order 8. NucuMBMTACEiE. Silicula indehiscent, few-seeded.

Tribe 8. UatidetB, Isatis tinetoria^ the Woad, has compressed, pendulous,
unilocular, one-seeded fruits (Fig. 407 F) : the leaves yield a blue dye.

Sub-o^der 4. Lohentacsjs. Fruit a siliqua or silicula, constricted into one-
seeded segments (lamentaeeoui) (Fig. 407 G).

Tribe 9. Cakilinea, Silicula two-jointed.
This tribe contains the genera Cakile, the Sea-
Boeket, and Crambe, the Sea-Kale.

Tribe 10. Raphanea, Silicula more or less
moniliform. Raphanut satiwu is the Radish ;
JR. RaphanUtrum, the Wild Radish or White
Charlock, is a common weed.

Order 4. Capparidaceje. Flower iso-
bilateral ; formula K2 + 2,Cx4yA2 +
2* or X , G^^ or x : stamens 4 or more,
when 6 very rarely tetrad jnamons :

sfyneeceam borne on a special proloncra- '"'•• 408.— Flower of CapparU
7. £ ,, . , 1 Arltr\ tptttOM (nat. 8i«e): .pedicel; k

tion of the axis (gy nopbore, p. 495) calyx; c copoIU; a stamens; /

(Fig. 408 t). Fruit a siliqua or a berry, gynaeceum on (0 gynophore.

The flower-buds of CapparU $pinoia from the South of Europe are known as
Capers.



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606 PABT III. — THE CLASSIFICATION OF PLANTS.

Order 5. RESEDACBiK. Flowers irregular, dorsiventral : sepals
and petals 5-8, the latter laeiniate : stamens nameroas : carpels
2-6 connate, forming a unilocular ovary, open at the apex, with
numerous ovules ; seed without endosperm : inflorescence a
raceme, without bracteoles.

Reseda Luteola^ the Dyer's Weed, or Weld, yields a yellow dye ; JR. odorata is
Mignonette.

Order 6. Cistacej;. Flowers usually actinomorphic and penta-
merous : the two external of the 6ve sepals are generally smaller,
and sometimes they are absent : stamens numerous, in conse-
quence of multiplication : carpels 3-10, forming a uni- or multi-
locular ovary; ovules orthotropous ; seed with endosperm.
Trees or shrubs with generally opposite stipulate leaves.

CistuB has 5-10 carpels forming a chambered or completely multilocular ovary.
Citttu ladanifemSf creticus, and other species, grow in the south of Europe ;
a balsam is derived from them. Helianthemum has a unilocular trimerous
ovary : Helianthemum vulgaret the Rock Bose, is an under-sbrub which grows
wild on dry soils.

Order 7. BiXACEiE. The seed of Bixa orellana, a native of

America, yields an orange- col cured dye known in commerce as

Annatto.

Order 8. Violacej:. Floral formula Kb, 05, A6, (?<« : flowers

always borne laterally : ovules anatropous : fruit a loculicidal

capsule (Fig. 4090): seed
with endosperm. The
indigenous species have
irregular dorsiventral
flowers ; the anterior in-
ferior petal is prolonged

, into a hollow spur (Fig.

I 409 ^ cs) in which the

nectar secreted by the
spur-like appendages of

F,G.409.-F«,la tncolor. ^ Longitudinal section of *^'® ^"^"^ ^°.^®^ StameUS

flower: « bracteole on the peduncle; I sepals; U ap- Collect.S (Fig. 409 A fs).

pend^e ; c petaU ; c. Bpur of »he lower pe»ta , /. rpj^^ ^^ j^ ^ produced
glandular appendage of the lower stamens ; a an- '^ ^

thej-8 (after Sachs). B Ripe fruit: fc caljx. C After at the baSC (Fig. 409

dehiscence : p parietal placenUe ; s ^eeds. (Mag.) ^ lg\

Viola is the Violet, Pansy, or Heart's-ease :— many species, as F. odorata, the
Sweet Violet, have only an underground stem which bears cataphyllary leaves,




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DICOTYLBDONKS : POLTPETAL-S : TBALAMIFXORA.



607



and which throws op petiolate foliage-leavei, and hracteolaie pednneles each
bearing a single flower : V, odarata has mnners, but hirta and eollina haTe
none:— in others, ae V, canina^ the Dog-Violet, the main stem is above ground
and bears the foliage-leayes : — in V. mirahilis these two forms are so combined
that, in tbe spring, flowers are developed from the rhizome which have large blue
petals but are always sterile ; it is not till later that inconspicaons (deistoga-
mons, p. 453) flowers with minute petals appear on the leafy stem, and these
only are fertile: — in V, tricolor and its allies the Btipolea are leafy and
pinnatifid.

Cohort V. Sarraceniales. Flowers regular, generally actino-
morphic, sometimes monochlamydeoas : stamens often numerous,
ovary syncarpons, uni- or malti-locular ; placentation various;
seeds many, with endosperm ;
leaves adapted in various ways
for the capture of insects.

Order 1. SARRACENIACEiB.

Flowers 5j visually dichlamy-
deous, hemicyclic : stamens 15
or more : ovary either unilocular
and more or less chambered, or
3- or 5 -locular ; placentation pa-
rietal or axile : leaves pitchered
(Pig. 410).

This order includes the three her-
baceous genera Sarracenia, Darling-
tonia, and Heliampbora. Tbe two
former have pentamerous dichlamy-
deoQS flowers, each borne' singly on a
peduncle; the sepals and petals are
in } arrangement, and the stamens
are indefinite in Sarracenia and 15 in
Darlingtonia ; carpels 5, antisepalous
in Sarracenia, antipetalous in Dar-
lingtonia: they grow on moors and
marshes in North America. Heliam-
pbora bears its flowers in racemes ;
the flower has a simple petaloid peri-
anth, indefinite stamens, and a trilooolar ovary; it is a native of British
Guiana.



Fie» 410.— Leaves and flowers of Sarra-
cenia purpurea {\) : the leaf to the left has
been ont aoroes.



Order 2. NEPENTHACEiK. Flowers dioecious, monochlamydeous,
tetramerous : stamens generally 4-16, coherent into a central
column : ovary quadrilocnlar, with axile or somewhat supei^cial
placentation: leaves pitchered (Fig. 37, p. 58).

V. 8. 6. R R



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608 PART III. — THE CLASSIFICATION OP PLANTS.

Tbi« tropical order includes the single genus Nepenthes, with aboot 40
species, chiefly, inhabiting the Malay Archipelago, but extending to Ceylon,
Australia, the Seychelles, and Madagascar: they are mostly climbing shrubs
with leaf-tendrils.

Order 3. DROSERACKiB. Flowers 5» ^^chlamydeons, generally
pentamerous : stamens 5 or 5" : carpels 2-5 ; ovary nsually uni-
locular with parietal placentiB : leaves not pitcliered.

Herbaceous plants, constituting the six genera Dionea, AldroTanda, Boridula,
Byblis, Drosera (the Sundew) and Drosopbyllum : in Dionsa, Aldrovanda, and
Drosophyllum, the gynseceum consists of 5 antipetalous carpels, and the OTary
is unilocular ; in Drosera and Boridula the gyneceum is usually trimerous, the
ovary unilocular in the former, trilocular in the latter ; in Byblis it is dimerous
and bilocular. The leaf -blade of Dionsba (Venus* fly-trap) and of Aldroranda
is sensitive to touch, tbe two halves closing sharply along the middle line when
irritated : the leaves of the other genera are provided with irritable glandular
tentacles (see Figs. 42, 43, p. 66). Aldrovanda (A, vetieuloia) is a rootless,
floating water-plant.

Cohort VI. Guttiferales. Flowers usually cyclic, generally
actinomorphic, and pentamerous: sepals usually free, with
imbricate sBstivation: stamens usually indefinite: gynsoceum
syncarpous, ovary uni- or multi-locnlar : seed ezalbaminoas.

Order I. Hypericacejb. Formula usually Kb, C5, -40 + 5oo,
&^^ ; or ^0+ 3oo, QQ)- Sepals sometimes united at the base: sta-
mens usually indefinite and polyadelphous ;
when in five bandies, the bundles are super*
posed on tbe petals ; this position of the
stamens is generally attributed to the sup-
pression of an outer whorl of stamens which.
is indicated by staminodes in species of all
the genera : ovary uni- or multi-locular, or
Fio. 411. — iMagram of many-chambered ; capsule septicidal ; ovules
Hypericum, numerous, anatropous; placentie parietal or

axile. Herbs or under-shrubs with decnssate entire leaves, which
are dotted over with translucent oil-glands ; ezstipnlate.

Tbe following are examples of the different relative numbers of staminal
bundles and of carpels : —

Staminal bundles 5, carpels 5 : Hypericum calycinwn,

Staminal bundles 8, carpels 3 : U. humifutum^ hirtuttLm, moiUoMim, per*

faratum, undulatunif barbatum,
Staminal bundles 5, carpels 8 : H, Androiamum, hircinum, elatum*
Staminal bundles 8, carpels 5 : H, pepUdifoUum,
All these species, except the last (St John's Worts, or Tutsans), occur wild in
Britain.



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DIC0TYLED0NE8 : POLTPITALJ: : THALIMIFLOR*. 609

Order 2, Tamabicaoba. Flowers 4- or S-merous, with one op
two whorls of stamens : calyx gamosepaloas : ovary nsaally tri-
meroas, nnilocnlar, with basal or parietal placentation : capsnle
locnlicidal : seeds with hairs : flowers in racemes or spikes.

This order inolodes the shmbs known as Tamarisks: Mjrioaria, Tamariz,
Beaomoria, and Fonqoiera. Myriearia {Tam&rix) germanica has monadelphoos
stamens. Tamarix gaUiea (or T, angliea) has become natoralised in England.

Closely allied with this order and with the Elatinaee» is the small order of
FRANKBNiAcSiB ; the flower resembles that of Tamariz in the gamosepalons
oalyz and in the morphology of the gynascenm : Frankenia UbvU, the Sea-Heath,
occurs in salt-marshes in Britain.

Order 3. Elatinaogjc. Small water-plants, with entire stipulate
leaves opposite or in whorls: flowers 3-4-meron8 ; formula Kn^
Cn, ^n + n, ff^ ; solitary, without bracteoles, borne in the axils of
the foliage-leaves: ovary multilocular.

E, hexandra and Hydfopipfr (Waterworts, or Water-peppers) ocenr, bnt not
commonly, on the margins of lakes in England.

Order 4. TERNSTBOiMUCEiB, Perianth spiral ; the calyx is not
clearly distinguishable from the numerous bracteoles : stamenA in-
definite: ovary multilocular. Trees or shrubs with scattered,
generally coriaceous, entire leaves, without stipules.

CamelUa japonica is a faTonrite ornamental shmb : Tkea eHnetuU^ of which
the dried leaTes are tea; black and green tea are varieties resulting only from
the mode of drying the leaf.

Order 5. Glusiacej: (Guttifkrb). Trees or shrubs with di-
clinous flowers.

Order 6. DiPT&ROCARPACEiB. Trees : leaves usually stipulate :
the gamosepalons calyx enlarges very much during the ripening xA
the fruit.

Dryohalanopt Camphora, a natiye of Sumatra, yields the Borneo Camphor.

Cohort VIL Mai vales. Flowers cyclic, generally pentamerous
and actinomorphic : calyx often gamosepalons, with valvate aesti-
vation: corolla with usually contorted aestivation: stamens typi-
cally in two whorls, frequently obdiplostemonous, sometimes
branched, and often connate : carpels usually five and then anti-
petalous, often forming a multilocular ovary : seed usually with
endosperm.

Order ]. TiLUCBii. Sepals usually free: stamens 10 or
indefinite, sometimes polyadelphous ; in the indigenous species the



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610



PART III. — THE CLASSIFICATION OF PLANTS.



Itl



staminal ivhorl opposite to the sepals is sappressed, and there are
5 antipetalons staminal bundles; anthers 4-localar, opening by
pores or valves : gynsBceara usually completely syncarpous ; style
1 ; ovary usually 5-locular, each loculus containing two ovules ;
but the fruit is generally only one-seeded. Mostly trees or
shrubs: leaves alternate, stipulate.

The only indigenoos genus is Tilia, the Lime-tree. It has oblique leaves with
deciduous stipules ; the annual shoots have not a tenxunal bud. The inflor-

escenoe is oymose, few* flowered : the
peduncle is adnate to the leafy bract ;
this is brought about in the following
manner: in the axil of the leaves
there is usually a bud» together with
an inflorescence (Fig. 412) : the bract
(Fig 412 h) and the bud-scale, which
is opposite to it, are the first two
leaves of the axillary shoot which is
terminated by the inflorescence, the
peduncle of which is adnate to the
bract for some distance : the bud is a
winter-bud developed in the axil of
the above-mentioned bud-scale. The
inflorescence itself terminates in a
flower ; other flowers are borne in the
axils of its two braoteoles, and other
flowers again may be developed in the
axils of their bracteoles, and so on.
7. platyphyllos, the large-leafed Lime,
has a few-flowered inflorescence, and
leaves which are bright green and
downy on the under surface : T. cor-
data has an inflorescence which con-
sists of a large number of flowers, and
has small leaves which are bluish-
green and pubescent with red hairs on
the under, surface. T. nUgarU is the
common Lime. In the American
species the innermost stamens are
staminodia. Gorchorus, in the East
Indies, yields Jute, which consists of
the bast- fibres.



Fio. 412.— Inflorescence of the Lime, TUia
platyphyVos: a branch; h petiole with
ftzillary bud. Attached to the pednncle is
the bract (H) : k calyx ; e corolla; s stamens;
/ovary; kn flower-bud (nat. site).



Order 2. Stkrculiack*.
Calyx gamosepalous : andrcBcium obdiplostemonous ; the stamens
which are opposite to the petals are 5 or multiple, sometimes
more or less monadelphous ; those which are opposite to the



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DIC0TTLBD0NE8 : POLYPETALiE : THALAMIFLORJC. 611

sepals are staminodes or they are suppressed : anthers 4-Iocalar :
the corolla is sometimes wanting : gynsecenm usually syncarpons,
with a single style and a 5-localar ovary with 2-qo seeds in each
loculns. Flowers sometimes diclinous (Sterculieae).

Theohromo Cacao is a tree of tropical America, the seeds of vhich contain a
nitrogenous snbstaDce Theobromine and a fixed oil ; from them Chocolate is
prepared. The seeds of ola acuminata^ a tropical African tree, have similar
properties.

Oi*der 3. Malvacea. Calyx nsnally gamosepalous, frequently
invested by an epicalyx (p. 494) ; the corolla is adnate at the
base to the androecium : the typically obdiplostemonous androe-



FI6.4I3.— il Flower of Malva Alc4a (nat.size): k calyx; c corolla; < connate stamens,
with the anthers (a); n stigmata. B Fruit of AlthcBa ro8«a enclosed in (k) the calyx: oic
epicalyx. C The same after the removal of the calyx. D A single coccus of the same in
loiigitadinal section : • seed ; w radicle ; •( cotyledon of the embryo (mag.).

cium is a long tube (Fig. 413 A) consisting of five monadelphons
nsualiy branched stamens which are opposite to the petals, each
branch bearing a bilocular anther ; there is sometimes an inner
series of staminodes opposite to the sepals : carpels 5-qo ; styles
many, connate; the gynsBcenm is sometimes almost apocarpous
(Malopese) ; usually syncarpous with a multilocular ovary, split-
ting into cocci (Fig. 413 G D), with usually one ovule in each
coccus (p. ^30), or a loculicidal capsule (Hibiscese), Under-
shrubs or herbs : leaves stipulate and genei'ally palmately veined.

Malva, the Mallow, has an epicalyx of three bracteoles. Hibiscus has one of
many bracteoles, and Altbsa has one of 6-9 bracteoles : Althaa rosea is the



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612 PART m«*^THB CLASSIFICATION OF PLAIITS.

Hollyhook/and A, qffieinaUt is the Marsh-mallow : seTeral species of MalvA are
indigenoas, M. tyloettrit, rottmdifolia, and mo9chata : Oostypium herbaeeum
(with the Tars. religio$um and hinutum) and G. arboreum in Egypt and the East
Indies, and O. barhadenae (with rar. peravianum) in America, yield Cotton,
which consists of the long bairs on the testa of the seed,

SSBIES IL— DISCIFLOB^.

Flowers typically encyclic and generally pentamerons, often
obdiplostemonons : sepals free or coherent : petals in a single whorl :
stamens nsnally definite, and hypogynons: a disc is nsnally present :
gynaecenm generally syncarpons.

Cohort I. Geraniales. Flowers nsnally pentamerons throngh-
out; formula Kb, (75, | ^5 + 5, G® ;' generally obdiplostemonons:

the carpels are opposite to the petals :
ovary nsnally 5-locnlar, with 1 or 2
suspended ovnles; the micropyle is
directed inwards: disc various or
wanting.

Order 1. Geraniaceje. Disc usually
represented by a gland at the base of
and outside each of the antisepalous
stamens : flowers nsnally aotinomor-
phic : stamens connate at the base :
the carpels are prolonged into a car-
pophore (Fig. 414 A a) ; two ovules in
each locnlus; the fruit is septicidal
from below upwards, the awns of the
separating carpels (cocci) rolling up
n i^^g' ^1^ ^)' Seed devoid of endo-

sperm. Herbs ; leaves simple, stipn-

Tig. 414.— Fruit of Geraniom. A \atQ
Before, B aOer dehiscence ; • pe- *

dicel ; / locali of the ovary ; ainB Geranium has 10 stamens : in most species



Online LibrarySydney Howard VinesA student's text-book of botany → online text (page 60 of 83)