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.
=A.= Capsule opening at the side by pores and small valves: _Campanula_
(Canterbury-bell); the corolla is bell-shaped, rarely almost rotate;
capsule obconical. ~The pores of the capsule are found near the top of
the fruit when it is erect, and near the base when it is pendulous, so
that the seeds are not liberated unless the capsule is forcibly shaken,
and they are thus ejected to a considerable distance.~--_Phyteuma_
(Rampion) has free petals, which for a long time adhere at the
apex and form a tube round the stamens (Fig. 601); inflorescence
compact, spike-like or capitate, in the latter case resembling
that of the Compositæ, and frequently with an involucre similar to
the one possessed by this order. ~_Specularia_ (rotate corolla,
prismatic capsule), _Michauxia_ (flower 8-merous).--_Symphyandra_ has
syngenesious anthers.~
=B.= Capsule with valves at the apex, loculicidal dehiscence:
_Jasione_; the petals are almost free. The anthers are united at the
base (syngenesious). The flowers are situated in capitate umbels with
involucres.--_Wahlenbergia_; _Platycodon_.
[Illustration: FIG. 601.--_Phyteuma spicatum._ Flowers and parts
of flowers in various stages of development.]
=C.= Berry: _Canarina_; flower, 6-merous; leaves opposite.
Protandry is general (Fig. 601). 510 species; principally in temperate
countries. Several genera furnish ornamental plants, but are of
little use for other purposes. The roots of some _Campanula_-and
_Phyteuma_-species are large and may serve as pot-herbs (_C.
rapunculus_, _P. spicatum_).
Order 2. =Cyphiaceæ.= In this order the corolla is zygomorphic and the
stamens free, hence it is intermediate between orders 1 and 3.--About
24 species; Africa.
Order 3. =Lobeliaceæ= (=Lobelias=). This order may briefly be described
as Campanulaceæ with _zygomorphic_ flowers and anthers _united into
a tube_, in most cases slightly bent; generally 2 carpels and an
_inverted_ position of the flower, _i.e._ the median sepal is turned
anteriorly (Fig. 602) (a position which is found to occur within the
Campanulaceæ). A twisting of the peduncle takes place even before
flowering (as in the Orchids) so that the ordinary position of the
5-merous Dicotyledons appears to be restored. The zygomorphy of the
flower is especially present in the corolla, which has a _bipartite_
under-lip and a _tripartite_ upper-lip, and is, in _Lobelia_,
anteriorly (apparently posteriorly) deeply cleft (Fig. 602). There
is 1 style, but the stigma is capitate and bilobed and surrounded
at its base by a _whorl of hairs_, which assists in pollination
(as a stylar-brush) in the same manner as the sweeping-hairs in the
Campanulaceæ and Compositæ. There is _no terminal flower_ in the
spicate, or racemose inflorescences.--_Lobelia_ has a capsule, several
others have berries. ~_Isotoma_ (regular flower); _Heterotoma_ has a
spur; _Siphocampylos_; _Lysipoma_ (pyxidium); _Clintonia_ (1–locular
fruit). _Metzleria_ (all the petals are free).~
[Illustration: FIG. 602.--Diagram of _Lobelia fulgens_.]
[Illustration: FIGS. 603, 604.--_Lobelia syphilitica._
FIG. 603. Flower (2/1).