Exclusively trees or shrubs with simple, entire, scattered leaves
without stipules. They have a _strongly perigynous_, regular,
_4-merous_ flower. The receptacle (often coloured) envelopes a simple
gynœceum formed of =1= _carpel_ and with, in most cases, =1= ovule,
bearing on its edge 4 (or 5) petaloid sepals and, but rarely at the
same time, small, scale-like petals. The corolla is most frequently
entirely wanting (and hence these plants were formerly reckoned among
the Monochlamydeæ); frequently only one of the 2 whorls of stamens,
which are situated on the inner side of the edge of the receptacle, is
developed. The fruit is most frequently a _1-seeded_ berry or drupe, or
a nut which may be falsely berry-like, the partly persistent receptacle
being fleshy and enveloping it.
This family appears the most nearly allied to the Frangulinæ,
especially the Rhamnaceæ, and may be considered as a further
development of these in the direction of the petaloid
development of the receptacle and reduction of the corolla and
gynœceum, which in this instance only consists of one carpel.
Another deviation is that both the whorls of stamens are
present, while one of these is always wanting in Frangulinæ.
They also appear to be related to the Lauraceæ (see page 391).
Order 1. =Thymelæaceæ.= The flowers are most frequently ☿ (Fig. 483).
The receptacle is high, generally tubular, coloured, and bears on its
edge the 4-(or 5)-merous calyx, with imbricate æstivation. The corolla
is wanting or is represented by small scales. The stamens are situated
on the inside of the receptacle, and number 4 + 4 (or 5 + 5); stigma
capitate. 1 _pendulous ovule_ (Fig. 483 _B_), the _radicle pointing
upwards_. The fruit is most frequently a berry. ~A disc is sometimes
developed. Endosperm wanting or very slight.~
[Illustration: FIG. 483.--_Daphne mezereum_: _A_ flower; _B_
longitudinal section of pistil.]
_Daphne_ (Spurge-Laurel, Fig. 483) has a deciduous receptacle, often
coloured; sepals 4; petals absent; stamens 4 + 4. Berry.--_Gnidia_
(corolla); _Pimelea_ (2 stamens); _Thymelæa_; _Passerina_ and others.
400 species; chiefly in the warm, sub-tropical zone, especially
the Cape and Australia. Only _Daphne_ and _Thymelæa_ in
Europe. In the fruit and bark of some, for example _Daphne_,
pungent, burning and poisonous properties are found. The bark
of _D. mezereum_ (native and cultivated) and _D. laureola_ is
officinal. A specially tough bast is found in some species, for
example _Lagetta lintearia_ (Lace-tree, Jamaica), which is used
in weaving. Some are cultivated in gardens as ornamental shrubs,
especially species of _Daphne_.
Order 2. =Elæagnaceæ.= Shrubs or trees, which are easily recognised
by the covering of _peltate hairs_ found upon almost all parts of the
plant, causing them to assume a _silvery_ or rusty-brown appearance.
Stipules are absent; the leaves are simple, most frequently scattered.
Flowers (Figs. 484, 485) frequently unisexual. The sepals are
valvate, 2-4; the _corolla is wanting_; _stamens_ 4 + 4 or 0 + 4.
The ovule is _erect_ and _the radicle turned downwards_ (Fig. 486).
The fruit is a _nut_, but becomes _a false fruit_, being surrounded
by the persistent receptacle or the lower part of it, and thus
assuming a berry- or drupe-like appearance (Fig. 486). Endosperm
insignificant.--_Shepherdia_ (opposite leaves) has 4 sepals, 4+4
stamens, as in _Daphne_. Diœcious.--_Elæagnus_ (Silver-leaf) is ☿,
has 4–6 sepals, and 4–6 stamens alternating with them. _Hippophaë_
is diœcious; it has 2 sepals and 4 stamens in the ♂-flower (perhaps
properly speaking 2+2 stamens); thorny (stem-structures).
16 species; especially ornamental shrubs, _e.g. Elæagnus
argentea_, _angustifolia_; _Hippophaë rhamnoides_ and
_Shepherdia canadensis_. Northern Temp.
[Illustration: FIGS. 484–486.--_Elæagnus angustifolia._
FIG. 484.--Floral diagram.
FIG. 485.--Longitudinal section through the flower.