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.
[Illustration: FIG. 593.--_A_ Diagram of _Valeriana officinalis_.
_B_ Diagram of _Centranthus_.]
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.
[Illustration: FIG. 594.--_Valeriana_: _A_ ovary (longitudinal
section); _B_ ripe fruit.]
[Illustration: FIG. 595.--_Valeriana_: _a_ flower in the ♂ stage;
_b_ in the ♀.]
[Illustration: FIG. 596.--_Centranthus ruber._ Flower, its
lowermost portion (the ovary and spur) in longitudinal section.
(Mag.)]
[Illustration: FIG. 597.--_Scabiosa atropurpurea._ Fruit in
longitudinal section. Inside the “epicalyx” may be seen the fruit
drawn out into a beak, with straight embryo and radicle directed
upwards.]
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_.
[Illustration: FIGS. 598–600.--_Dipsacus fullonum._
FIG. 598.--Inflorescence (the flowers in a zone below the apex
commence to flower first).
FIG. 599.--Flower (4/1).