=A.= =The fruit a capsule=, ~most frequently with loculicidal
dehiscence, and many seeds in each loculus~.
=1.= GOSSYPIEÆ. The staminal-column is naked at the apex, blunted, or
5-dentate.--_Gossypium_ (the Cotton plant) has an epicalyx of 3 large
ovate-cordate leaves, an almost entire, low and compressed calyx.
Solitary flowers. Large, most frequently yellow, corollas. A 3–5-valved
capsule with many spherical seeds. “Cotton” is the seed-hairs developed
upon the entire surface of the seeds (Fig. 447), and consists of long,
1-cellular hairs, filled with air (and therefore white); these are
thin-walled, with a large lumen, and during drying twist spirally,
and come together more or less in the form of bands. They consist
of cellulose, and have a cuticle.--_Hibiscus_ has several, most
frequently narrow, epicalyx-leaves, a distinct 5-toothed or 5-partite
calyx.--_Abutilon_; _Modiola_.
[Illustration: FIG. 447.--_A_ Seed of _Gossypium_ with hairs; _B_
the same in longitudinal section.]
=2.= BOMBACEÆ. The staminal tube is more or less deeply cleft
into bundles, sometimes almost to the base; pollen smooth,
style simple with capitate, lobed stigma. Almost all plants
belonging to this group are trees, and in many instances have
large barrel-shaped stems, that is, swollen in the centre, and
sometimes covered with large warts. The wood is exceptionally
light and soft. The flowers are often enormously large, and have
beautiful petals; in some they unfold before the leaves. The
capsule-wall is sometimes closely covered on its inner service
with long, silky, woolly hairs, while the seeds themselves
are generally without hairs. These hairs, however, on account
of their brittle nature, cannot be used like those of the
Cotton-plant. Digitate leaves are found in the _Baobab-tree_
(_Adansonia_) from Africa, noted for its enormously thick, but
short stem, and in the American _Silk-cotton trees_ (_Bombax_,
_Eriodendron_, _Chorisia_). _Ochroma_, _Cheirostemon_, _Durio_,
and others also belong to this group. _Durio_ is noted for its
delicious fruits, which have a most unpleasant smell.
[_Bombax malabaricum_ is diplostemonous; the five sepal-stamens
repeatedly branch, and the filaments bear unilocular anthers;
the five petal-stamens bear bilocular anthers.]
=B.= =Schizocarps=, with 1-seeded fruitlets, most frequently nut-like
and reniform (Figs. 449, 451).
=3.= MALVEÆ, MALLOW GROUP. The carpels are arranged in one whorl
(Fig. 449); the number of stylar-branches equals that of the
carpels; fruitlets 1-seeded, reniform, indehiscent, but detaching
themselves from one another and from the persistent central column
(Figs. 450, 451).--~_Malva_ has an _epicalyx of 3 free leaves_. ~A
flower with 2 suppressed bracteoles is situated in the axil of the
foliage-leaves; one of these supports a homodromous foliage-shoot
which forms a repetition of the main axis, the other an antidromous
flower which continues the branching as a unipared scorpioid
cyme.~--_Althæa_, Rose Mallow, has an _epicalyx of 6–9 leaves united at
the base_.--~_Lavatera_, _Sida_, _Anoda_, _Bastardia_, etc., have no
epicalyx.~
[Illustration: FIGS. 448–451.--_Malva silvestris._]
[Illustration: FIG. 448.--The flower after removal of the
perianth (5/1).]
[Illustration: FIG. 449.--The fruit (5/1).]
[Illustration: FIG. 450.--A fruitlet (5/1).]
[Illustration: FIG. 451.--The same in longitudinal section.]
=4.= URENEÆ, have always only 5 carpels arranged in 1 whorl,
with 1 ovule in each loculus, and the fruit a schizocarp,
generally with nut-like fruitlets provided with warts and
hooks; but in some they dehisce by 2 valves (capsule). They
differ principally from the other groups _in having twice as
many stylar-branches as carpels_; the staminal tube is naked at
the point, blunt or 5 toothed.--The genera _Urena_, _Pavonia_,
_Malachra_, _Malvaviscus_ (with _berry-like fruits_) belong to
this group.
II. Carpels arranged in a spherical head in five groups opposite to the
petals.
=5.= MALOPEÆ, differ from all the others in having a large
number of fruitlets arranged irregularly in a round head, and
separating considerably from each other even before maturity;
there is, however, only 1 style, divided into a corresponding
number of branches (this condition may be considered to have
arisen from the branching [dédoublement] of 5 _carpels_).
_Malope_ has 3 large, heart-shaped (_Kitaibelia_ 6–9)
epicalyx-leaves, united at the base. _Palava_ has no epicalyx.
POLLINATION. The majority have protandrous flowers, and are
pollinated by insects. Between the basal portions of the 5
petals, there are 5 nectaries, protected from the rain by
hairs, _e.g._ in _Malva silvestris_. When the flower first
opens the numerous anthers occupy the centre of the flower, and
the still undeveloped stigmas are concealed in the staminal
tube; in the next stage the anthers are withered and empty,
and the stigmas protrude and assume their places (Fig. 452).
The large-flowered forms, it appears, are pollinated only by
insects; but self-pollination takes place in small-flowered
forms, as, for example, in _Malva rotundifolia_, in which the
stylar-branches, twisting themselves, place the stigmas in
between the undeveloped anthers.
[Illustration: FIG. 452.--_Anoda hastata_: _a_ the bud just
opened, the stigmas are concealed by the anthers; _b_ fully
opened flower in ♂-stage; the upper stamens are developed first,
and then the others in descending order; the stylar-branches
are now visible, and lie bent back on the staminal column; _c_
all the stamens project upwards, and all the anthers are open,
but the stylar-branches are still bent back; d the anthers are
emptied and the filaments shrunk together, but the styles have
now straightened themselves upwards, and the stigmas are in the
receptive condition.]
DISTRIBUTION. 800 species (63 genera), most of which are
natives of the Tropics, especially America. _Althæa_ and some
of the species of _Malva_ are natives of the temperate regions
of the Old World, the latter is also found in North America.
_Gossypium_ is tropical, no doubt especially Asiatic (_G.
herbaceum_ from India; _G. arboreum_ from Upper Egypt). Cotton
was introduced into Greece in the time of Herodotus, and was
cultivated in America before the arrival of the Europeans.
USES. Pungent and poisonous properties are entirely wanting;
_mucilage_, on the other hand, is found in abundance in all
parts of the plant. Medicinal: the root of _Althæa officinalis_,
leaves and flowers of _Malva_-species (_M. silvestris vulgaris_
and _borealis_) and _Gossypium_.--The seeds contain a large
quantity of _fatty oil_, which is in some cases extracted
(Cotton-seeds and others). _The seed-hairs of the Cotton
plant_ are the most important product of the order. The
cultivated forms of Cotton belong to several species: _G.
barbadense_, _herbaceum_, _religiosum_, _arboreum_ (Nankin),
_hirsutum_, and others. According to other botanists, there
are only 3 species. _Bast_ is obtained from _e.g. Hibiscus
cannabinus_ (Gambo-hemp, Africa), _Paritium tiliaceum_ and
_Sida retusa_. The fruits of certain species of _Hibiscus_
(_e.g. H. esculentus_, from Tropical Africa) are used in
tropical countries as a vegetable before they are ripe.--_The
colouring matter_ in the flowers of _Althæa rosea_, var.
_nigra_, is used for colouring wines, and hence is extensively
cultivated in certain parts of Europe.--_Ethereal oils and
sweet-scented flowers_ are rare; but several species possess
a peculiar musk-like odour (_Malva moschata_, _Hibiscus
abelmoschus_, and others).--Many are cultivated as _ornamental
plants_ on account of the large flowers, _e.g._ Hollyhock (_A.
rosea_, etc.), _Lavatera trimestris_, _Malope grandiflora_ and
_trifida_, _Malva_-species, _Hibiscus rosa sinensis_, _syriaca_;
_Sphæralcea_, etc.