Chapter II: ACROGYNÆ. The apex of the stem or of certain branches is adapted (13)

The INFLORESCENCES are often double unipared scorpioid cymes;
the bud of the second bracteole is developed, that of the first
suppressed; in some cases both the bracteoles are suppressed
(_Myosotis_, _Omphalodes_, etc.), but in other instances all
the first bracteoles (_a_) only are suppressed, and the others
are then situated in two rows towards the under side of the
coiled axis, while the flowers are situated on the upper side.
Displacement of the branches or of the floral-leaves sometimes
takes place. The flowers are often red at first, and later on
become blue or violet; they hardly ever have any smell. The
fruit entirely resembles that of the Labiatæ, but the radicle
of the latter is turned downwards. The fruitlets present small
differences which have systematic importance; they are hollow or
flat at the base, attached to a flat or columnar receptacle, etc.

=1.= HELIOTROPIEÆ. This group deviates from the characteristics mentioned above in the undivided ovary and terminal (“apical”) style. In this, as well as in the fact that in some genera (_Tournefortia_, _Ehretia_, etc.) the fruit is a drupe, it connects this order with the Cordiaceæ. _Heliotropium_, _Tiaridium_, and others have schizocarps.

=2.= BORAGEÆ, BORAGE GROUP. Style gynobasic; fruit a schizocarp.

=A.= The throat of the corolla is without ligules, or with very small ones.--_Pulmonaria_ (Lung-wort); funnel-shaped corolla; a whorl of hairs in the corolla-throat.--_Echium_ (Viper’s-bugloss) has zygomorphic flowers, the plane of symmetry almost coinciding with that of the very well-developed inflorescence (through the fourth sepal); the corolla is obliquely funnel-shaped, the style is more deeply cleft at the apex than in the others; stamens 2 longer, 2 shorter, and 1 still shorter.--_Cerinthe_ has a tubular corolla with five small teeth and two bilocular fruitlets. The bracts are large and leafy, and, like all the rest of the plant, are _almost glabrous_.--A few _Lithospermum_-species have a naked corolla-throat; others have small hairy ligules, which do not close the corolla-throat. The fruitlets are as hard as stone, owing to the presence of carbonate of lime and silica.--_Mertensia_ (_Steenhammera_); _Arnebia_; _Nonnea_ (small ligules).

=B.= The corolla-throat is closed by, or in any case provided with _ligules_, _i.e._ scale-like bodies or small protuberances, situated in the throat of the corolla _opposite_ the petals, and which are invaginations or _internal_ spurs of the petals (Fig. 572 _D_).--The nuts in _Cynoglossum_ (Hound’s-tongue) bear _hooked bristles_ over the entire surface, or, in _Echinospermum_, only on the edge. The following have smooth nuts:--_Symphytum_ (Comfrey) has a cylindrical, campanulate corolla, and prolonged-triangular, pointed ligules.--_Borago_ (Borage) has a rotate corolla with projecting, emarginate ligules; the stamens have a horn-like appendage, projecting upwards from the back of the filament. The fruitlets are hollow below.--_Anchusa_ (Alkanet, Fig. 572). The corolla is salver-shaped; the ligules small, hairy protuberances. _A. (Lycopsis) arvensis_ has an S-curved corolla-tube.--_Myosotis_ (Forget-me-not, Fig. 573); rotate corolla with small (yellow) protuberances in the throat; scorpioid cyme without floral-leaves; fruitlets flat.--_Omphalodes_; fruitlets hollow at the back, with a scarious, turned-in, toothed edge.--_Asperugo_ (Mad-wort); the calyx grows after flowering, becoming large, compressed, and deeply bifid.

CROSS-POLLINATION is most commonly effected by insects
(especially bees). There are a great many contrivances for
pollination; some flowers are protandrous (_Echium vulgare_,
_Borago officin._), others are heterostylous (long-and
short-styled: _Pulmonaria officin._); the corona (ligules) is
a protection against rain, and excludes certain insects. Some
are barren when self-pollinated (_Pulmonaria officinalis_,
_Echium vulgare_); others which have but little honey, may,
failing insect-pollination, fertilise themselves, and in
_Myosotis versicolor_ this regularly occurs by the growth of the
corolla during flowering, so that the anthers are brought into
contact with the stigma. Honey is secreted on the hypogynous
disc.--About 1,150 species, growing especially in the northern
temperate zone, _Mucilage_ is found (_e.g._ in the _officinal_
root of _Cynoglossum officinale_, in the root of _Symphytum_):
red _dyes_ are found in some roots (_e.g._ Alkanet-root, the
root of _Alkanna tinctoria_, which is also medicinal; S. E.
Europe, Asia Minor); some are _poisonous_: _Cynoglossum_,
_Echium_, _Anchusa_, etc. Several species are ornamental plants.
_Heliotropium_ (Peru) is cultivated chiefly on account of its
pleasant scent; essential oils are otherwise very rare.

Order 3. =Verbenaceæ.= The majority are shrubs; a few are herbs or trees (Teak-tree); some are lianes. The branches are often square. The leaves are opposite or verticillate, without stipules; in some compound. The inflorescences are racemes, spikes, capitula, or dichasia. Five sepals; five petals in a gamopetalous, zygomorphic corolla, which is often bilabiate, but rarely to such an extent as in the Labiatæ, and the upper lip in some is larger than the under, in others smaller; stamens four didynamous, or two; the ovary is entire (not grooved or divided), 1- or 2-locular, or, as in the Labiatæ, divided into four loculi with an _erect_ ovule in each, but in some the anterior carpel is suppressed. One _terminal_ style. The fruit is, _e.g._ in _Verbena_, a 4 partite schizocarp with nut-like fruitlets; in _Vitex_ (digitate leaves) a drupe with a 4-locular stone; in _Clerodendron_ a similar fruit, with four free stones; in _Lantana_ a bilocular stone, or two unilocular stones. The radicle is _turned downwards_. Endosperm small or absent.--_Lippia_, _Stachytarpheta_, _Bouchea_, _Priva_, _Citharexylon_, _Callicarpa_, etc.--The Verbenaceæ are closely allied to the Labiatæ; they differ especially in the ovary not being 4-lobed with gynobasic style, but undivided, almost spherical or ovoid with a terminal style. Again, the leaves are not so constantly opposite, and the inflorescences are various.

730 species; especially in the Tropics; there are several in
America, especially _Lantana-species_; shrubby weeds.--Many of
those mentioned are ORNAMENTAL PLANTS, especially _Verbena_;
_Vitex agnus castus_ is a S. European shrub. _Lippia citriodora_
(S. Am.) etc., have strongly-scented leaves; the Teak tree
(_Tectona grandis_) is one of the largest trees in East India,
and has a very hard wood.

_Avicennia_ is allied to this order; it inhabits the Mangrove
swamps on tropical coasts. The endosperm emerges from the ovule,
carrying the embryo with it; the embryo ultimately bursts the
endosperm and lies free in the loculus of the fruit; this is
then filled by the embryo with its large, green cotyledons,
which are borne on an already hairy or rooted stem. The seedling
thus developed falls from the tree, together with the fruit, and
strikes root in the mud. One special cell of the endosperm at
an earlier period becomes a highly-developed organ of suction,
growing into a much-branched sac, very rich in protoplasm.

Order 4. =Labiatæ.= The special characteristics are: the _square_ stem, the _opposite leaves_ (without stipules), the inflorescences which are formed by _two double unipared scorpioid cymes_, the _labiate_ corolla, the 4 _didynamous_ stamens (the posterior being entirely suppressed) (Fig. 574), and the _4-partite schizocarp_ with _nut-like fruitlets_. The floral formula is S5, P5, A5 (the posterior stamen is generally absent), G2.

They are chiefly aromatic plants (herbs, shrubs, _e.g._ Lavender, or trees), volatile oil being formed in internal cells or in the glandular hairs, which cover all green parts. The stem is always more or less markedly square; the leaves are borne upon the flat sides, and are simple and penninerved, but vary in the other characters. The inflorescences are double unipared scorpioid cymes, which may be situated at some distance from one another in the axils of the foliage-leaves (Fig. 575 _A_), but frequently when the subtending leaves are bract-like, they are crowded into spike-like inflorescences (_Lavandula_, _Mentha_, _Salvia_, etc.), each of the so-called “whorls” (verticillaster, glomerulus) being a double unipared scorpioid cyme (Fig. 574). (Solitary flowers are found in _e.g._ _Scutellaria_, and _Origanum_). The calyx is strongly gamosepalous, 5-toothed, often bilabiate (Fig. 575 _B_). The corolla is strongly bilabiate (Figs. 575, 576, etc.), with 2 lobes in the upper lip and 3 lobes in the under lip (an approach to regularity occurs only when the upper lip is small, and thus resembles one lobe, as in _Mentha_ (Fig. 578) and _Lycopus_, so that the corolla approaches the 4-merous corolla of _Veronica_ and _Plantago_). The posterior stamen in the diagram (Fig. 574*) is entirely suppressed; in most of the genera the posterior lateral stamens are the smaller (Fig. 575 _D_), and are entirely suppressed in some (see below); in others, _e.g._ _Nepeta_, they are the longer. 2 stamens are found in _Salvia_, _Rosmarinus_, _Lycopus_, etc. The two halves of the anthers are often separated from one another, and are placed at an angle with each other. The gynœceum has 1 style with a bifid extremity (Fig. 575 _C_) bearing the stigma; the true bilocular ovary is divided by a false partition-wall into 4 loculi, each with 1 erect ovule (Fig. 575 _H_). These 4 loculi project so strongly that the ovary becomes deeply 4-lobed with the style situated in the centre of the lobes and at their base, “gynobasic” (Figs. 575, 579). A ring-like, often crenate, nectary surrounds the base of the ovary (Fig. 575 _G_, _H_). The embryo in this order, as in the _Verbenaceæ_, is directed downwards (Fig. 575 _J_) (it is directed upwards in the _Boraginaceæ_, which have an entirely similar fruit). _Endosperm absent._

The 142 genera are mainly distinguished according to the form of
the calyx and corolla, the number, direction, and length of the
stamens, the forms of the nuts, etc.

=1.= AJUGEÆ, BUGLE GROUP. Calyx 10-nerved; the upper lip is small; 4 stamens. The ovary is not so strongly lobed as in the following group, so that it is most nearly allied to the _Verbenaceæ_. The nuts are reticulately wrinkled. _Ajuga_ (Bugle) has a very small upper lip. The upper lip of _Teucrium_ (Germander) is deeply cleft, and the two lobes are bent on their respective sides towards the under lip, which in consequence appears to be 5-lobed, and the upper lip to be wanting.

=2.= STACHYDEÆ, BETONY GROUP. The calyx is 5- or 10-nerved. The upper lip of the corolla is most frequently _strongly arched_ or helmet-shaped; 4 stamens, the _anterior pair the longer_ (Fig. 576).

=a.= A somewhat regular and 5–10-dentate calyx with _projecting_ stamens.--_Stachys_ (Betony, Woundwort); the lobes of the under lip are rounded off. The anterior filaments, after pollination, _bend outwards_. _Betonica_--_Ballota_ (Horehound); the calyx is funnel-shaped, and has triangular, long, pointed, awn-like teeth.--_Galeopsis_ (Hemp-nettle) has two conical protuberances on the under lip between the lateral and the central lobes. The anthers open by 2 _unequal_ valves. _Lamium_ (Dead-nettle, Fig. 576) has dentate, lateral lobes on the under lip. _L. album_ (White Dead-nettle), _L. rubrum_, etc. _Galeobdolon._--_Leonurus_; _Phlomis_.

=b.= Tubular, regular, often 10-toothed calyx and _concealed_ stamens.--_Marrubium vulgare_ (Fig. 577); 10 calyx-teeth, hooked at the apex; many almost spherical whorls of flowers in the axils of the foliage-leaves, at some distance from one another.--_Sideritis._

=c.= Strongly bilabiate calyx, the lips _closing together_ after flowering.--_Scutellaria_ (Skull-cap); the two lips of the calyx are entire, the upper lip has a large spur, and drops off on the ripening of the fruit. The flowers are generally solitary and turned to one side.--_Prunella_ (Heal-all); the calyx is compressed, its two lips are strongly dentate, the upper lips closing slightly round the under. The stamens have a tooth-like projection beneath the anthers.

=3.= NEPETEÆ, CATMINT GROUP. 13–15 nerves in the calyx; this deviates from the other groups in the _posterior stamens being the longer_. The upper lip is slightly arched. _Nepeta_ (Catmint), also _Glechoma_ (Ground Ivy), with regular, and _Dracocephalum_ with irregular calyx.

=4.= SATUREIEÆ, MINT GROUP. The upper lip is _flat_, most frequently ovate, or almost spherical, and emarginate (Fig. 578). The calyx is most frequently 5–10-nerved. 4 stamens, _the anterior being the longer_; rarely, 2 stamens only.--_Mentha_ (Mint, Fig. 578) has a regular, 5-dentate calyx, a small, almost regular, 4-partite corolla, and 4 erect stamens of nearly equal size. The verticillasters are many-flowered, and are often collected into cylindrical inflorescences. Herbs.--_Lycopus_ (Gipsy-wort); corolla almost regular. 2 stamens, the posterior lateral ones are wanting. _Preslia_: 4-dentate calyx, 4-partite, regular corolla; 4 stamens of equal size.--_Thymus_ (Thyme, Fig. 575) has a strongly bilabiate calyx, the throat being closed by a whorl of hairs (Fig. 575 B). The corolla is distinctly labiate. Under-shrubs, with small entire leaves; verticillasters few-flowered and separate.--_Origanum_ (Marjoram); spike or capitate inflorescences with the flowers solitary in the axils of the rather large and distinctly 4-rowed (often slightly coloured) floral-leaves. _Melissa._ _Calamintha._ _Clinopodium_ (Wild Basil). _Satureia._ _Hyssopus_ (Hyssop); small, entire leaves; the verticillasters are situated unilaterally in a slender, spike-like inflorescence. _Lavandula_ (Lavender); shrubs with verticillasters collected in cylindrical, long-stalked inflorescences; the calyx is tubular, has 13–15 nerves, the posterior tooth is much larger than the others. Stamens and style do _not_ project. ~_Coleus_ differs, among other characters, in having united filaments; the stamens and style are bent down and concealed in the boat-shaped under lip.~

=5.= MONARDEÆ, SALVIA GROUP. _Only the 2 anterior stamens are developed._--_Salvia_ (Fig. 579); calyx deeply bilabiate; the upper lip of the corolla is generally strongly compressed. Rudiments of the two lateral stamens are present. The connective in the two fertile stamens is long and filamentous, and bears at the upper end a normal half-anther, but at the lower one a barren, often broader portion, against which the insect is obliged to push its proboscis during its visits to the flowers, causing the pollen-bearing half-anther to be pressed down against its back. Floral-leaves often coloured.--_Rosmarinus_ (Rosemary); a shrub with leathery linear leaves, with rolled back edge. A small tooth on the filament represents the barren half of the anther. _Monarda._

The POLLINATION is generally effected by insects, especially
bees; the under-lip is the landing-stage and the pollen is
deposited on their backs. Cross-fertilisation is promoted by
dichogamy; honey is secreted by an hypogynous disc and collected
in the corolla-tube. Some genera are homogamous (_Lamium_,
_Galeopsis_, etc.); others are dichogamous (protandrous); a
few are _gynodiœcious_: ♀-and ☿-flowers in various relative
sizes (_Glechoma hederaceum_, _Thymus_, _Salvia pratensis_,
and others). The entrance of uninvited guests to the honey is
often rendered difficult by whorls of hairs, etc. In numerous
instances the upper lip protects the pollen from rain.
_Cleistogamy_ is found _e.g._ in _Lamium amplexicaule_.

2,700 species; distributed over the entire globe, but the
greater number in Mediterranean countries (especially in the
Eastern regions), where many are shrub-like.--Poisonous and
acrid properties are absent. On account of their _volatile oils_
they are principally used as _condiments_, for _perfumery_
and in _medicine_ (the officinal parts are therefore nearly
always “folia” and “herba,” in _Lavandula_ the flowers, and
the volatile oils extracted from them). Such are:[39]_Mentha
piperita_ [+] (Peppermint)--menthol is obtained from this
species and from _M. arvensis_--_M. viridis_ [+] (Spearmint),
_M. crispa_ (Curly-mint), _Thymus vulgaris_ (Garden Thyme),
_Melissa officinalis_ (S. Eur.), _Hyssopus officinalis_
(Hyssop, S. Eur.), _Origanum majorana_ (Marjoram, from the
Mediterranean), _O. vulgare_ (Wild Marjoram), _creticum_,
_smyrnæum_, etc., _Salvia officinalis_ (S. Eur.), _Rosmarinus
officinalis_ (oil of Rosemary, S. Eur.), _Lavandula vera_ [+]
(oil of Lavender, S. Eur.). Also: _Satureia hortensis_ (S.
Eur.), _Ocimum basilicum_ (E. India), _Pogostemon patchouli_
(E. India), etc.--As _ornamental_ plants, _e.g._ _Monarda_,
_Plectranthus_, and _Coleus_ (foliage-plants, often with red
stems and leaves), _Stachys lanata_ (white, woolly), _Phlomis_,
_Salvia_-species, _Perilla_, etc.

Order 5. =Selaginaceæ.= 130 species; small, most frequently
heath-like shrubs or herbs, mainly from S. Africa. They
differ from the other Nuculiferæ especially in the bilocular,
transversely-placed anthers of the 4 stamens (2 stamens
divided as far as the base (?)). The ovary has 2, or by
suppression only 1 loculus, each with 1 ovule, and the fruit
is a schizocarp dividing into two, or is a 1-seeded nut.
Radicle turned upwards.--A few are ornamental plants (_Selago_,
_Hebenstreitia_).

Order 6. =Globulariaceæ.= 12 species; especially in the
Mediterranean. They form an analogy to the Compositæ, and in the
main resemble _Jasione montana_ in appearance, the flowers being
crowded into a spherical head (hence their name) and supported
by bracts, but _without_ involucre; the ovary is _unilocular_
with 1 pendulous ovule. The _1-seeded nut_ is enveloped by the
persistent calyx. The corolla is more or less labiate, the
upper-lip is often absent as in the ligulate corollas of the
Astereæ; stamens 4, didynamous, with transversely placed anthers
opening by one transverse cleft. The leaves are scattered,
simple, entire, and generally form a rosette. _Globularia._

Order 7. =Stilbaceæ.= Heath-like shrubs. The ovary is bilocular;
1 erect seed in each loculus, or the posterior cell is empty.
_Stilbe._ 7 species. S. Africa.

Family 32. =Contortæ.=

_Hypogynous_, regular, ☿, gamopetalous flowers (Figs. 581, 582), which are generally 5- or 4-merous, with 5 or 4 stamens (with the exception of _Oleaceæ_ and _Jasminaceæ_ which have _only_ 2 stamens, alternating with the carpels). The gynœceum is formed of 2 (nearly always median) carpels. The corolla _very frequently has twisted æstivation_ (the upper edges of the petals being free; Fig. 581 _A_), and hence the individual lobes of the corolla are oblique, but the flower as a whole is regularly actinomorphic. A nectary, in the form of a honey-secreting ring or glands, is often found round the base of the ovary.--The leaves, with a few exceptions, are _opposite_ and _without stipules_. Endosperm large (Fig. 581 _C_), except in _Jasminaceæ_ and _Asclepiadaceæ_.

The Apocynaceæ and the Asclepiadaceæ, on account of the free
ovaries, without doubt represent a more primitive form, but the
Asclepiadaceæ on the other hand form an offshoot on account of
their peculiar pollen-masses. The Loganiaceæ form a transition
to the Rubiaceæ.

The orders are:--

A. STAMENS 5. 1, Gentianaceæ; 2, Apocynaceæ; 3, Asclepiadaceæ;
4, Loganiaceæ.

B. STAMENS 2. 5, Oleaceæ; 6, Jasminaceæ; 7, Salvadoraceæ.

Order 1. =Gentianaceæ= (=Gentians=). _Glabrous_ herbs, without latex; the opposite, undivided and _entire_ leaves are often slightly united at the base; many have rosette-like radical leaves. _Stipules absent_. The flowers are generally borne in regular, dichotomously-branched _dichasia_ (Figs. 580, 581 _A_), which finally become transformed into unipared scorpioid cymes; the parts of the flower are 4–5-merous as far as the gynœceum, which is 2-merous; the calyx frequently is almost polysepalous; the corolla has distinctly twisted æstivation (the upper edges being free) (Fig. 581 _A_), except _Menyantheæ_. The carpels are _entirely_ united, and most frequently form a _1-locular_ ovary with 2 _parietal placentæ_ bearing many ovules (often in several rows, Fig. 581 _D_, _F_). _Capsule_, 2-valved, with septicidal dehiscence, the incurved edges bearing the seeds (Fig. 581 _D_, _F_).

=1.= GENTIANEÆ.--_Gentiana_ (Gentian) has most frequently a tubular, campanulate or funnel-shaped corolla, sometimes with teeth between the corolla-lobes and fringed in the throat of the corolla; _G. lutea_ has a rotate, yellow corolla.--~_Swertia_: rotate corolla; each lobe has at its base 1–2 nectaries, with fringed edges.~

_Erythræa_ (Centaury, Fig. 581); corolla most frequently salver-shaped. The anthers ultimately become spirally twisted (_E_). The style prolonged, deciduous. The flower has the _Lobelia_-arrangement, _i.e._ the median sepal is anterior; the corolla is rose-coloured (in the native species). The capsule is semi-bilocular (Fig. 581 _F_, _G_).--~_Cicendia_ has a low creeping stem, fine as a thread, and small, yellow flowers, 4-merous (without twisted anther).--_Chlora_ (Yellow-wort) 6–8-merous.~

=2.= MENYANTHEÆ. _Menyanthes_ (Buck-bean) deviates in several respects from the type of the order. The leaves are _scattered_ and, in _M. trifoliata_, trifoliate; the corolla has _valvate_ æstivation; the testa is also very hard (thin in the true Gentians). They are aquatic plants with creeping rhizome; the flowers borne in racemes, with terminal flower, heterostylous. The corolla is funnel-shaped with a very hairy throat.--~_Limnanthemum_ with floating leaves, like the Water-lilies.~

575 species; distributed over the entire globe, but most
numerous in _Alpine_ districts. Neither poisonous nor nutritive
plants are found, but several are used in medicine on account of
the _bitter_ properties so prevalent amongst them. OFFICINAL:
the roots of _Gentiana lutea_. The roots of other species,
_e.g._ _G. purpurea_, _punctata_ and _pannonica_ (Europe) and
the leaves of _Menyanthes trifoliata_ are medicinal. Some are
grown as ornamental plants on account of the pure (often deep
blue) colour of the flowers.

Order 2. =Apocynaceæ= (=Periwinkles=). Trees and shrubs (also lianes), less frequently herbs, generally _with latex_. The leaves are opposite, simple, entire, _without stipules_; the flowers are regular; corolla-lobes oblique, æstivation twisted. The stamens are individually free, and the _pollen-grains are free_ or at most united in fours (see Asclepiadaceæ). The two carpels have 2–∞ ovules, in all cases there is only 1 style and a capitate stigma, which towards the base is widened out into a disc-like table (stigma-disc) abstricted in the centre; but the carpels in most of the genera (_e.g._ those mentioned below) are entirely separate, and the fruit consists of two _follicles_, the seeds of which often have a tuft of _woolly hairs_ projecting from the micropyle, less frequently of two drupes. In some other genera there is a 1-locular (provided with 2 parietal placentæ) or a 2-locular ovary becoming a 2-valved capsule or a berry. Endosperm abundant.

_Vinca_ (Periwinkle) has a salver-shaped corolla, which is twisted to the left in æstivation (_i.e._ the left edge of the petals is free); nectaries 2, alternating with the carpels; the summit of the style is hairy. Follicles; seeds without hairs. ~Mostly creeping, perennial, evergreen plants, whose large flowers are apparently axillary; in reality they are terminal, but by the development of the bud in the axil of one of the two uppermost leaves, they are thus displaced over the other leaf of the pair (a helicoid sympodium being formed).--_Plumeria_, _Tabernæmontana_, _Cerbera_ (drupe). _Aspidosperma._~

_Nerium_ (Oleander). The leaves are in whorls of 3. Corolla funnel-shaped, in æstivation twisted to the right, and with a corona resembling that of _Lychnis_. The anthers are prolonged at the base and each also bears at the apex a long, linear, hairy appendage; these finally become spirally twisted. Follicles; seeds hairy. _Apocynum_, _Echites_, etc. _Epigynum_ is epigynous.

124 genera, 1,000 species; principally in the Tropics. Only 2
species of _Vinca_ are natives of this country; the following
are cultivated as ornamental plants:--_Vinca minor_, _V. major_,
_V. (Lochnera) rosea_, _Amsonia salicifolia_, _Nerium oleander_
(Eastern Mediterranean). The _latex_ of some is _poisonous_
(_Tanghinia venenifera_, _Cerbera_). Caoutchouc is obtained from
others (_Hankornia_, _Landolphia_, _Vahea_, etc.). Tough bast is
frequently developed. The bark of _Aspidosperma quebracho_ and
the seeds of _Strophanthus hispidus_ are used in medicine (also
for African arrow-poison), the latter is officinal.

Order 3. =Asclepiadaceæ.= A natural and easily recognised order, closely allied to the Apocynaceæ, having, like it, frequently a poisonous latex, opposite, single, entire leaves and fundamentally the same floral diagram and floral structure (S5, P5, A5, G2); but in some the æstivation of the corolla is valvate. The carpels here also have _free ovaries_, but are united for some distance above into a _large, shield-like, 5-angular head_, having on its underside the true stigmas, and the fruit always consists of 2 _follicles_; seeds most frequently numerous and _hairy_ at the micropyle (“vegetable silk”); endosperm scanty.--The order is distinguished from the Apocynaceæ and from all other plants also, except the Orchids, by having all the pollen-grains in each of the =2= loculi of the anthers (true 2-locular anthers) united into _one waxy, club-shaped pollen-mass_ (“pollinium”), for the purpose of pollination by insects. These heavy masses, in order to secure pollination (as in the case of the Orchids), must be attached to sticky discs (corpuscula); there are 5 corpuscula, one at each of the corners of the 5-angular stylar-head (alternating with the anthers), and to each of these are attached 2 pollinia, one from each of the anthers situated on either side (thus each anther gives its right pollinium to one corpusculum and its left to another). The stamens are frequently united at the base, and each bears on the back a variously formed, petaloid appendage, termed a “cucullus.”

A peculiar relative position (and therefore a good, distinctive characteristic) is often found in the _inflorescence_, which is cymose; it is placed _between_ the two leaves of a whorl, nearer to one than to the other. ~The leaf-pairs are placed obliquely in the floral region, at acute and obtuse angles, and not at right angles (as in the purely vegetative parts); the inflorescences are placed in two rows only which are nearly 90° from each other, and the two contiguous to one another are antidromous; they are in reality terminal, each on its own axis, and the entire floral portion of the shoot is a unipared scorpioid cymose sympodium; in addition, complications also arise through individual parts becoming united.--Herbs and shrubs, some twining or climbing.~

In _Asclepias_ the corolla is bent back and there is a cup-like cucullus, from the base of which protrudes a horn-shaped body, bent inwards.--_Vincetoxicum_ has a rotate corolla and a ring-like, 5-lobed cucullus, without internal prominences.--~_Stapelia_ (especially from S. Africa) is remarkable on account of its Cactus-like, leafless stems and large, brownish flowers, often with carrion-like smell. _Periploca_ has more powdery pollinia (S. Eur., etc.); _Hoya carnosa_ (Wax-flower; Trop. Asia) is a climber, and has small, annual, flower-bearing dwarf-branches. _Ceropegia._~

201 genera with 1700 species, distributed over all tropical
countries; few outside these limits: no native species. Several
are used in medicine on account of the pungent properties of the
latex. Condurango-bark of _Gonolobus condurango_ is medicinal.
Caoutchouc is obtained from the latex of some (_e.g._ from
_Cynanchum_). The seed-hairs, which are most frequently shining,
silk-like, and white, are not sufficiently pliant to be of much
value. Ornamental plants in our gardens: _Asclepias_-species,
etc.

Order 4. =Loganiaceæ.= Ovary single, with two loculi, in
structure resembling the Rubiaceæ, but superior. 360 species
are included in this order; the majority are tree-like, some
lianes which climb by tendril-like branches. The _interpetiolar
stipules_ of some species are very characteristic (as in
Rubiaceæ, to which they maybe considered to be closely related).
The fruit is a capsule or berry. The most familiar genus
is _Strychnos_, which has spherical berries with an often
firm external layer, and compressed seeds with shield-like
attachments; endosperm abundant. The leaves have 3–5 strong,
curved nerves proceeding from the base.--_Spigelia._--They
have _no latex_, as in the two preceding orders, but many are
_very poisonous_ (containing the alkaloid “strychnine,” etc.);
the South American arrow-poison, urare or curare, is made from
various species of _Strychnos_, also an arrow-poison in the East
Indian Islands (Java, etc.). OFFICINAL, the seeds of _Strychnos
nux vomica_ (“Vomic nut,” Ind.). The seeds of _Strychnos
ignatii_ (Ignatius-beans, medicinal), and others are poisonous.

Order 5. =Oleaceæ.= The leaves are always opposite. The inflorescences are racemes or panicles. The calyx and corolla are _4-merous_, more or less united, free in some species; the corolla has most frequently _valvate_ æstivation. All four forms of fruit occur (see the genera). _Ovules pendulous_, 2 in each loculus (Fig. 583 _C_). Endosperm oily.--_Syringa_ (Lilac) and _Forsythia_ (anthers somewhat extrose) have _capsules_ with loculicidal dehiscence and winged seeds.--_Fraxinus_ (Ash) has _winged nuts_ (samara) (Fig. 583 _D_); trees with most frequently imparipinnate leaves; the flowers are _naked_ and sometimes unisexual (polygamous), the Manna Ash (_F. ornus_) has however a double perianth with 4 free petals (Fig. 583 _a_); in the native species, _F. excelsior_, the flowers open before the foliage appears.--_Ligustrum_ (Privet) has _berries_.--_Olea_ (_O. europæa_; Olive) has _drupes_; the pulp and seeds of the ellipsoidal fruits are rich in oil. The lanceolate leaves are grey on the under surface, being covered with stellate hairs. In the wild state it is thorny (modified branches).--_Phillyrea_; _Chionanthus_.--Few species of _Linociera_ have 4 stamens.

180 species; chiefly in the northern temperate zone. The
_Olive-tree_ (_Olea europæa_) has been an important cultivated
plant from ancient times (Olive oil, Provence oil, “Sweet oil”).
The best oil is extracted from the fruit-pulp. The fruits are
edible. Home: Western Asia, Eastern Mediterranean. TIMBER:
the Ash (_Fr. excelsior_). OFFICINAL: the Manna Ash (_Fr.
ornus_), cultivated in the Mediterranean countries for the
sake of its saccharine juice, which flows out and coagulates
into “Manna.”--The following are ornamental plants: species of
_Ligustrum_ and _Syringa_ (introduced in the 16th century, from
S.E. Europe and Asia), _Forsythia_ (China, Japan; the large,
yellow flowers are borne on dwarf-branches with scale-like
leaves, before the opening of the foliage-leaves), _Chionanthus_.

Order 6. =Jasminaceæ.= The æstivation of the corolla is
_imbricate_; the _ovules are erect_; seeds almost without
endosperm; radicle directed downwards. The number of lobes
in the calyx and corolla is not 4, but _e.g._ 5, 8, 10,
and variations are sometimes found in the same individual.
The fruit is a berry or capsule. Many species are twiners,
and their scattered or opposite leaves are most frequently
imparipinnate.--120 species; especially in Trop. Asia (E.
India). Some _Jasminum_-species are cultivated as ornamental
shrubs in the warmer districts on account of their elegant
foliage, and beautiful, sweet-scented flowers, the essential
oil of which is also used in perfumery; the best known are: _J.
sambac_ and _grandiflorum_. _Nyctanthes arbor-tristis_ opens its
sweet-scented flowers only at night (E. India).

Order 7 (?). _Salvadoraceæ._ 8–9 species; Asia,
Africa.--_Salvadora._

b. Tetracyclicæ with epigynous flowers.

Family 33. =Rubiales.=

_The leaves are always opposite or verticillate. The flower is epigynous_, ☿, 5-(or 4-) merous, with the usual sympetalous diagram; 2–5 carpels. The inflorescences are frequently dichasial. The sepals are small, reduced to teeth, and become almost entirely suppressed in the higher forms.--The flower is regular in _Rubiaceæ_ and some _Caprifoliaceæ_, but in other genera of this latter order (especially of _Lonicereæ_) it is unsymmetrical. In several genera of the order first mentioned the loculi of the ovary contain many ovules, but in the last the number of loculi and ovules becomes reduced. This is to some extent connected with the nature of the fruit which is many-seeded in most instances, namely a capsule or berry, but in others nut-like. Endosperm is present.

The family on one side is allied to the Contortæ (not only
through the _Loganiaceæ_ but also through the _Apocynaceæ_), and
may be regarded as an epigynous continuation of this family; on
the other side it is allied to the Valerianaceæ and Dipsacaceæ.
Many points of agreement with the _Cornaceæ_ and _Araliaceæ_ are
also found, and in fact several Caprifoliaceæ are distinguished
from these by hardly any other feature than the gamopetalous
corolla.

Order 1. =Rubiaceæ.= Leaves opposite (or verticillate), undivided and entire, with _interpetiolar stipules_ (Fig. 586). Flowers epigynous and hermaphrodite, _regular_, 4- or 5-merous with the usual arrangement (Figs. 585, 588–590); corolla gamopetalous, in æstivation often valvate; ovary _frequently 2-locular_.

There are no external characters which at once distinguish
this exceedingly large order, as in many other natural orders
(Compositæ, Umbelliferæ, etc.), but the _opposite_ leaves with
_interpetiolar stipules_ form an excellent mark of recognition.
It is divided into many sub-orders and groups, especially
characterised by the nature of the ovary (1 or several ovules
in each loculus), and of the fruit (schizocarp, berry, drupe,
capsule).--The corolla is bilabiate in 4 genera; its æstivation
in some is twisted; in _Capirona_, etc., the filaments are of
unequal size. The ovary is semi-epigynous in _Henriquezia_, etc.
In _Morinda_ all the fleshy fruits coalesce into one multiple
fruit.

=1.= CINCHONEÆ. The fruit is a 2-valved _capsule_, with many winged seeds (Fig. 585). _Cinchona_ (Quinine, Fig. 584). Trees and shrubs with the foliage and inflorescence somewhat resembling _Syringa_; the corolla also being of a lilac colour, more or less salver- or funnel-shaped, and frequently edged with a fringe of hairs (Fig. 585), is somewhat similar to that of _Menyanthes_. Their home is the Andes from Bolivia to Venezuela, varying in altitude from 1–3000 metres. There are now large plantations in Java and E. India. ~(The name “quinine” is of Indian origin; that of the genus “_Cinchona_,” is from the Spanish Duchess Cinchon, who in 1638 first introduced the bark into Europe.) The following are closely allied: _Cascarilla_, _Remijia_, _Ladenbergia_, _Manettia_, _Bouvardia_, etc.~

=2.= GARDENIEÆ. Trees and shrubs, frequently having a many-locular berry. _Randia_, _Gardenia_, _Genipa_, _Hamelia_, etc.

=3.= COFFEEÆ. Only 1 seed in each of the two loculi of the ovary; _the fruit is a drupe with 2 stones_. _Coffea_ has an ellipsoidal fruit about the size and colour of a cherry; the two thin-shelled, parchment-like stones are enclosed by a thin layer of pulp; the two seeds are flat on the side turned to one another, which has also a deep, longitudinal groove curving to the sides. The endosperm is hard, horny and greyish (without starch); the small embryo lies in the lower end near the circumference. The Coffee-plant (_C. arabica_) is a small tree, or more frequently, and especially in plantations, a shrub with large dark-green leaves and scented, white flowers. Its home is in Tropical Africa; it is now cultivated in many tropical countries. _C. liberica_, W. Africa.--_Cephaëlis_ (_C. ipecacuanha_, Fig. 586; the roots are officinal).--~_Psychotria_, _Chiococca_, _Ixora_, _Hydnophytum_, _Myrmecodia_, etc.~

=4.= SPERMACOCEÆ. Chiefly small shrubs and herbs, many of which are weeds in tropical countries. The stipular sheaths bear numerous bristles at the edge. _Spermacoce_, _Borreria_, _Diodia_, _Richardsonia_, etc.

=5.= STELLATÆ. _Herbaceous plants with_ verticillate leaves (Figs. 587, 588–590); _the stipules are large, leaf-like_, and resemble the lamina of the leaves, so that _the leaves appear to be placed several in a whorl_, while in reality there are only two opposite leaves, the stipules of which project _freely_, and are not erect (Fig. 587).

In some cases there are apparently 4 leaves in the whorl, and then 2 of these are leaves, and the other two are their interpetiolar stipules. When there are apparently 6 leaves, then the two of these which are opposite each other are leaves, and the other four are stipules; if there are several members in the whorl, then a division of the stipules has taken place. The proof of this theory is founded upon the fact that not more than 2 of the leaves of the whorl ever support buds (which, in addition, are seldom of equal vigour), and also that the whorls do not alternate with each other, which, according to the rules of the position of the leaves, they should do if all the members of a whorl had equal value. If there are, for instance, 4 members in two successive whorls, they stand right above one another, and do not alternate. The development and anatomical relations (the branching of the vascular bundles) also point to the same conclusion.~--All the other groups of the order have only 2 small scale-like interpetiolar stipules, or they form at the base of the leaf-stalks an interpetiolar sheath, having often a toothed edge (Fig. 586).--Another characteristic feature in this group is that the calyx is rudimentary, the corolla _valvate_ (Fig. 588), and that each of the two loculi of the ovary has only 1 ovule. The fruit is a _schizocarp dividing into 2 fruitlets_ (Fig. 590). ~The forms of the fruit, as well as many other characters, as, for example, the epigynous flower, the rudimentary calyx, the two free or almost free styles, present interesting analogous resemblances to the polypetalous order of the Umbelliferæ.~ This group has its home chiefly in the temperate regions of the northern hemisphere, especially about the Mediterranean; it is the only group which occurs in this country, represented by 4 genera.

FIG. 588.--Diagram.

FIG. 589.--Longitudinal section of flower.

FIG. 590.--Longitudinal section of fruit (3/1).]

_Galium_ (Cleavers) is almost destitute of a calyx; it has a small _4-partite, rotate corolla_, 4 stamens, and 2 free styles. The fruitlets are _nut-like_. The inflorescence is a paniculate dichasium passing into helicoid cymes.--_Asperula_ (Woodruff) is distinguished from the above by its salver- or funnel-shaped corolla. 1 style.--_Rubia_ (Madder, Figs. 587–590) has almost the same form of corolla as _Galium_, but (most frequently) a _5-merous flower_, and the fruitlets are “_drupes_.” ~_Sherardia_ (Field Madder); the flowers are clustered in closely arranged cymes surrounded by _an involucre_; _the calyx has 6 distinct teeth_, while the number of petals and stamens is 4. The corolla is funnel-shaped.--_Vaillantia._ _Crucianella._~

The DISTRIBUTION OF SEEDS, in some instances, is promoted by
hooked appendages on the fruitlets (_e.g._ _Galium aparine_).

The small flowers of the Stellatæ are frequently collected
in compact inflorescences, and are therefore rendered more
conspicuous; slight protandry is found in some, self-pollination
in the species which are less conspicuous. Many species are
heterostylous. _Myrmecodia_, _Hydnophytum_, and other genera
have large tubers (hypocotyledonous stems), whose labyrinthine
cavities and passages are inhabited by ants.

About 4,500 species; tropical or sub-tropical except the
Stellatæ; especially American. The tropical ones are mostly
trees.--Several are ~OFFICINAL~ on account of the large
amount of _alkaloids_ and _glycosides_ which they contain. The
most important are the Cinchonas (_Cinchona calisaya_, _C.
succirubra_, _C. officinalis_, _C. micrantha_, etc.), whose bark
contains the well-known febrifuge and tonic, Quinine, Cinchonin,
etc.; Quinine is also found in _Exostemma_, _Ladenbergia_, and
_Remijia_. The root “Ipecacuanha” (an emetic) from _Cephaëlis
ipecacuanha_ (Brazils). Caffeine is officinal. The use of the
seeds of the coffee plant (“the beans”) was first known in
Europe in 1583.--There are only a few which contain _aromatic_
properties, principally among the Stellatæ (coumarin in
_Asperula odorata_, the Woodruff), in which group _colouring
materials_ are also found. The root and root-stalks of _Rubia
tinctorum_, the Madder (S. Eur., Orient., Fig. 587), were
formerly largely used for dyeing, but are now superseded by
the analine colours. Red dyes are also obtained from the roots
of species of _Asperula_ and _Galium_. Gambier is a splendid
colouring material, obtained from _Uncaria gambir_ (S.E. Asia),
which is used in dyeing and tanning.--The order does not furnish
many ornamental flowers.

Order 2. =Caprifoliaceæ.= This order agrees with the Rubiaceæ in having opposite leaves and an epigynous flower, most frequently 5-merous with the ordinary tetracyclic diagram, but in some species it is zygomorphic; the corolla has imbricate æstivation, _carpels 3–5, most frequently 3_ (not 2, which is the most usual number in the Rubiaceæ). The fruit is generally a _berry_ or a _drupe_, but the most important, and in any case most easily recognisable feature, is the _absence of stipules_; in exceptional cases, where they are present, they are not interpetiolar, and are most frequently small.--~The majority of plants belonging to this order are shrubs or trees. Compound leaves sometimes occur. Stipules only appear in a few species of _Lonicera_, _Sambucus_ and _Viburnum_; in the common Elder (_Sambucus nigra_) they are in some instances glandular and small, but in other cases larger and more leaf-like (upon long, well-developed shoots); in the Dwarf Elder (_S. ebulus_) they have the normal leaf-like form; in _Viburnum opulus_ they are present as narrow lobes at the base of the petiole; in others they are completely absent. The leaves are frequently penninerved, rarely palminerved. The calyx, as in the Stellatæ and Aggregatæ, is often very insignificant.~

=1.= LONICEREÆ, HONEYSUCKLE GROUP. This has _campanulate or tubular corollas_ which are often zygomorphic; in connection with the length of the corolla the _style is long, filamentous_, and most frequently has a large, capitate stigma. There are _several ovules_ in the loculi of the ovary, and the fruit is most frequently a _berry_.

_Lonicera_ (Honeysuckle). Shrubs, sometimes twiners. The corolla in some species is considerably bilabiate (Fig. 591), with 4 lobes in the upper lip, and 1 in the under lip, but in others more regular, tubular, or campanulate. The flowers are either borne in capitate inflorescences, which are compound and formed of closely compressed 3-flowered dichasia (sect. _Caprifolium_), or in dichasia with 2 flowers (the terminal flower is wanting). The ovaries and fruits coalesce in some (sect. _Xylosteum_). ~The opposite leaves in some species unite with each other and form a broad collar encircling the stem (Fig. 591). Above the primary bud 1–2 accessory buds are often found in the leaf-axils.--_Diervilla_ (_Weigelia_); with a 2-locular, 2-valved capsule.--_Symphoricarpus_ (Snowberry) has an almost regular, funnel-shaped corolla; a peculiar feature is found in the ovary which has 4 loculi, the 2 median having many ovules in 2 rows, all of which are aborted; the 2 lateral ones, on the other hand, each have only 1 ovule which is developed. Different forms of leaves are frequently found on the same branch; they are entire or lobed.~

=2.= SAMBUCEÆ, ELDER GROUP (Fig. 592). This has a _rotate_, _regular corolla_, extrorse anthers, a very short and thick (or almost absent) _style_, with tripartite stigmas, and only 1 pendulous ovule in each of the 3 (-5) loculi of the ovary. The fruit is a “_drupe_” with 1–3 (-5) stones. The inflorescence is made up of _cymes grouped in an umbel-like arrangement_.

_Sambucus_ (Elder, Fig. 592) has _imparipinnate_ leaves and a “drupe” with 3 (-5) _stones_. Between the calyx and the style a disc remains on the apex of the fruit. _S. nigra_ with black fruit; _S. racemosa_ with red fruit; _S. ebulus_ is a perennial herb; the others are woody.--_Viburnum_ (Guelder-rose) has _simple_ leaves (penninerved or palminerved, entire, dentate or lobed), and a “drupe” with only 1 _stone_, which is compressed, cartilaginous, and parchment-like; 2 of the loculi of the ovary are aborted. ~(In _V. opulus_ the marginal flowers of the inflorescence are barren, and in that case their corollas are generally specially large; the cultivated _Viburnum_ has only barren flowers, with large corollas.)~

=3.= LINNÆEÆ. _Linnæa borealis_ (the only species) is an extreme form of the order; it has a 2-flowered dichasium, funnel-shaped, slightly bilabiate corollas (2/3); 4 didynamous stamens. Two of the 3 loculi of the ovary have several ovules which are not developed, while the third has only 1 ovule, which developes into a seed. The fruit is a nut, which is enveloped by the two large bracteoles, which are covered by sticky, glandular hairs, and serve as a means of distribution. It is a small undershrub.

[_Adoxa_, which was formerly classed in this order, appears,
according to recent investigations, to be more properly placed
among the Saxifraginæ.]

In cases where the flowers are small, as in _Sambucus_ and
_Viburnum opulus_, they are rendered conspicuous by being
arranged in closely-packed inflorescences; they are massed
together and form large surfaces, and in the last named are
still more conspicuous on account of the barren, but large
ray-flowers, which are of service in this respect. Honey is
secreted in the nectaries at the base of the styles. In the
genera with rotate flowers, as _Viburnum_ and other Sambuceæ,
the honey lies so exposed and in such a thin layer, that only
flies and insects with short probosces can procure it; bees,
however, visit these flowers for the sake of the pollen. There
is hardly any nectar in the Elder; self-pollination frequently
takes place. The flowers of the Caprifoliaceæ, which, with their
long corolla-tube are adapted for evening-and night-flying
insects with long probosces, open in the evening, and at that
time give off their strongest scent.

DISTRIBUTION. 230 species; especially outside the Tropics in the
Northern Hemisphere. In this country they are found especially
in hedges and as under-shrubs.--OFFICINAL: the flowers and
fresh fruits of the Elder (_S. nigra_), the fruits (“berries”)
being also used in the household. ORNAMENTAL SHRUBS: species of
_Lonicera_, _Symphoricarpus_, _Diervilla_, which are chiefly
from N. Am., _Abelia_ and _Viburnum_.

Family 34. =Dipsacales.=

The leaves are _opposite and without stipules_. The flower (Figs. 593, 595, 598, 599, 600) is _epigynous_, _zygomorphic_ or _asymmetrical_, 5-merous with S5, P5, stamens typically 5, but by suppression _never more than 4_, sometimes less, carpels 3–2. The calyx is more or less insignificant, and almost suppressed in the extreme forms. The ovary has 3–1 loculi, but _only one loculus_ has an ovule, which is _pendulous_ with the micropyle _turned upwards_ (Fig. 594). Fruit a nut. Embryo straight, with the radicle _pointing upwards_ (Fig. 597), without or with endosperm.

The inflorescences are distinct dichasia in Valerianaceæ, but in Dipsacaceæ and Calyceraceæ they are crowded together into capitula.

This family is closely allied to the Rubiales through the
Valerianaceæ, which have almost the same structure as many
of the Caprifoliaceæ. It attains the highest development in
the Dipsacaceæ, which are composite plants, but differs from
Compositæ in the position of the ovule, etc.

Order 1. =Valerianaceæ.= Herbaceous plants or under-shrubs with opposite leaves, often pinnate; stipules absent. The flowers are borne in _dichasia_ and in _scorpioid cymose inflorescences_ and are _entirely without any plane of symmetry_ (Fig. 593). The calyx and corolla are 5-merous, but the calyx is frequently very insignificant and ultimately a pappus, as in Compositæ; the corolla is frequently saccate or produced into a spur at the base. Most frequently, only 3 (4–1) of the 5 stamens are developed; these are free. Carpels =3=, which form an inferior _ovary_, often with 3 _loculi_, but only _1 of the loculi_ contains =1= _pendulous, anatropous ovule_ (Figs. 593, 594 _A_), the other loculi are empty and shrink up more or less completely. (Compare Fig. 593 _A_, _B_). Style 1, stigma tripartite. Endosperm absent; embryo straight, with the radicle directed _upwards_.

The inflorescences are dichasia, or unipared scorpioid cymes
with the branches developed in the axil of the second bracteole.
Both the bracteoles are generally present and frequently form
4 very regular, longitudinal rows on the branches of the
inflorescence.--5 stamens do not occur (except perhaps in
_Patrinia_). The suppression of stamens and carpels takes place
most readily on the anterior side of the flower and that turned
towards the first bracteole (_a_) (Fig. 593), whose branch is
suppressed in the dichasium; after this the posterior median
stamen is next suppressed.

By the vegetative characters as well as by the inflorescence
and the flower, the order is allied to the Caprifoliaceæ and
especially to the Sambuceæ.

In the least modified (oldest) forms, _Patrinia_ and _Nardostachys_, there is an almost regular flower, a 5-merous calyx, 4 stamens, and 3 loculi in the ovary, 2 of which however are barren. The stamens in _Valerianella_ are reduced to 3, in _Fedia_ to 2 (posterior), and the calyx is less distinctly 5-dentate; the 2 empty loculi in the ovary are still visible. _Fedia_ has a small spur at the base of the corolla. _Valeriana_ has a very reduced, hair-like calyx (pappus), an unsymmetrical, salver-shaped corolla with a _sac-like_, nectariferous spur at the base, 3 stamens and only 1 loculus in the ovary (Figs. 594, 593). _Centranthus_ (Fig. 593) is still further reduced. The corolla has a spur and only 1 stamen; ~unipared scorpioid cymes with 4 rows of bracteoles. In the last two genera there is a peculiar wall in the corolla-tube, which divides it longitudinally into two compartments (indicated by a dotted line in Fig. 593), one of which encloses the style. This wall is low in _Valeriana_, but in _Centranthus_ it reaches as far as the throat.--The rays of the _pappus_ are pinnately branched and rolled up before the ripening of the fruit. 12–20 in number (Fig. 594 _A_, _B_).~

_Val. officinalis_ and others are protandrous: in the first
period the stamens project from the centre of the flower (Fig.
595 _a_), the stigmas in the second (_b_) when the stamens have
become bent backwards. (_V. dioica_ is diœcious with large ♂-and
small ♀-flowers).--275 species; especially from the temperate
and colder parts of the northern hemisphere of the Old World,
Western North America and the Andes.--_Bitter_ properties are
characteristic, such for instance as the volatile acid and
volatile oil of _Valeriana_; these occur especially in the
rhizomes. OFFICINAL; the rhizomes of _V. officinalis_.--The true
Indian “Nardus,” an important medicine and perfume in India,
is extracted from _Nardostachys_ (Himalaya). A variety of
_Valerianella olitoria_ is sometimes used as salad.

Order 2. =Dipsacaceæ= (=Teasels=). Herbs with _opposite_ leaves without stipules. The flowers are situated in compact capitula each with an involucre. A characteristic feature of the order is that _each flower_ of the capitulum has a _gamophyllous_ “_epicalyx_” (Figs. 597, 599, 600), which envelopes the inferior ovary. The flowers (Figs. 599, 600) are ☿, 5-merous (S5, P5, stamens typically 5, G=2=), but the calyx often expands at the edge into a membrane with 5, or an indefinite number of bristles or teeth (pappus, Figs. 597, 600), and the _zygomorphic, funnel-shaped corolla_ is sometimes 5-lobed and bilabiate (2/3), but most frequently 4-partite (Fig. 599), the two lobes of the upper lip coalescing into one lobe, as in certain Labiatæ, _Veronica_ and _Plantago_; the æstivation is _imbricate_.

FIG. 598.--Inflorescence (the flowers in a zone below the apex
commence to flower first).

FIG. 599.--Flower (4/1).

FIG. 600.--The same in longitudinal section.]

_The stamens are never more than 4_, the posterior one _remaining undeveloped_; they _usually have free anthers_ which generally project considerably (Fig. 599). The ovary is unilocular with 1 _pendulous_ ovule and bears 1 _undivided style_; fruit a nut with 1 _seed, containing endosperm_ and with the radicle turned _upwards_ (Fig. 597).

The flowers do not always open in centripetal order, a fact
which may be observed especially in the Dipsacaceæ, in which a
zone of flowers round the centre of the capitulum opens first,
and the flowering then proceeds both upwards and downwards
(Fig. 598). This has probably some connection with the fact
that the capitulum has arisen from the coalescence of several
dichasial inflorescences. In species of _Scabiosa_ the flowers
open simultaneously at the circumference, or in a zone at the
centre.--The morphological explanation of the “_epicalyx_”
is not quite certain; in all probability it is formed from
two united bracteoles, for an “epicalyx” is distinctly formed
in this way in one of the Valerianaceæ, _Phyllactis_.--The
_ray-flowers_ are larger and more irregular, labiate or
ligulate, than the disc-flowers, yet not in so high a degree as
in the Compositæ.

=A.= A scarious bract to each flower. _Scabiosa_ has a 5-lobed corolla; the “epicalyx” has a dry, scarious, often finally large collar, and the true calyx is formed of long bristles (generally 5) (Fig. 597). _Succisa pratensis_ (Devil’s-bit) has a 4-lobed corolla, the collar of the “epicalyx” is herbaceous; the calyx as in the preceding.--_Pterocephalus._--_Dipsacus_ (Teasel); large, spiny and stiff-haired herbs with capitula, or short, thick spikes on which both the involucral-leaves and bracts project considerably, and are stiff and spinose (Fig. 598). The “epicalyx” has short teeth, or is almost entire. ~The leaves of the stem unite together in pairs, so that shallow cups are formed round the stems in which rain-water may collect.--_Cephalaria._--_Morina_: the flowers are falsely verticillate as in the Labiatæ; the calyx has 2 laterally-placed, entire, or emarginate lobes; 2 stamens, or 2 large and 2 small ones.~

=B.= Bristles, but _no_ true bract to each flower. _Knautia_; the corolla is 4-partite, the calyx cup-like, with many bristles or teeth on the edge.

POLLINATION is in many species effected by insects. The
honey is secreted by a ring round the base of the style. The
flowers in our native species are considerably protandrous.
Gynodiœcious flowers also occur.--150 species; especially in
the Mediterranean and the Orient; the order is not represented
in the South Sea Islands, Australia and America.--The heads of
the true Teasel (_Dips. fullonum_) are used for carding wool, on
account of the elastic bracts, which are hooked at the point.
The order has bitter properties; tanin, etc.; but no species are
used in medicine or the household.--_Scabiosa atropurpurea_,
etc., are used as ornamental plants.

Order 3. =Calyceraceæ.= This order resembles the Compositæ in
the valvate æstivation of the corolla and the more or less
united stamens, and the Dipsacaceæ in the undivided style,
pendulous ovule and endosperm. The calyx is frequently composed
of 5 distinct scales. An “epicalyx” is wanting.--20 species;
America.

Family 35. =Campanulinæ.=

The flower is _epigynous_, perfect, with 5 sepals, 5 petals, and 5 stamens in regular alternation, and =3= (2–5) carpels. The sepals in all cases are _distinct_, but narrow and pointed, so that the æstivation is open. The corolla is gamopetalous with (as in the Compositæ) _valvate_, or slightly infolded-valvate æstivation. The stamens are nearly always _situated on the torus_ without being united to the corolla (Figs. 601, 604). The anthers adhere or unite and form a tube with introrse anthers from which the pollen is swept out by the projecting, brush-like hairs on the style (as in the Compositæ). The ovary is =3=-(2–5) locular, _many ovules_ in each loculus. The fruit is generally a _many-seeded_ capsule (or berry). Embryo in the centre of a fleshy _endosperm_.--The majority are herbs with scattered leaves, without stipules. The presence of _latex_ and _inulin_, together with the tubular formation of the anthers, the pollination, etc., indicate a relationship with the Compositæ.

The _Cucurbitaceæ_ are by some authorities placed in this family
as being most closely related to the Campanulaceæ. Although the
corolla is most frequently gamopetalous, and other similarities
to the Campanulaceæ are present, yet on account of the structure
of the ovule, and for other reasons, the Cucurbitaceæ are
here placed in the Choripetalæ. The Campanulinæ without doubt
proceed upwards to the Compositæ, with which, in addition to
the occurrence of inulin and laticiferous vessels (Cichorieæ),
there are many corresponding features both in the structural
and biological relations (epigyny, valvate æstivation of the
corolla, tendency of the anthers to adhere or unite, protandry
with a stylar-brush, etc.) The inflorescence of _Jasione_ is
almost identical with that of the Compositæ.

Order 1. =Campanulaceæ= (=Campanulas=). The flowers are _regular_ and in some only semi-epigynous, 5-merous, except in the gynœceum which is 3-merous (the unpaired, median carpel being generally posterior), more rarely 2–5-merous, and has a corresponding number of stigmas and loculi in the ovary; the placentation is axile with a large number of ovules. The median sepal is posterior. The stamens frequently have broad, free bases (Fig. 601 _H_) which cover the nectariferous upper surface of the ovary; the anthers only fit loosely together, and become separated as soon, as the pollen is shed (Fig. 601 _G_), 1 long style, which is studded by sweeping-hairs (stylar-brush), which ultimately become invaginated; the stigmas do not unfold until the stamens have shed the pollen (Fig. 601 _E_, _G_). Fruit a capsule.--Herbs, more rarely under-shrubs or shrubs, with latex and scattered, undivided leaves without stipules. The inflorescence is most frequently a raceme or spike _with_ terminal flower.