_Ricinus_ (Castor-oil) (Figs. 453–455); monœcious; the ♂-flowers,
situated in the lower portion of the inflorescence, have 5
perianth-leaves and a large number of branched stamens; the ♀-flower
has 3–5 perianth-leaves; 3 bifid styles. Leaves peltate, palmately
lobed. The seeds (Fig. 455) contain an abundance of fatty oil and
large aleurone grains.--_Mercurialis_ (Mercury): the perianth is most
frequently 3-merous; in the ♂-flowers 9–12 stamens; in the ♀-flowers
most frequently a _2-locular_ gynœceum.--_Phyllanthus_: Pr3 + 3, A3,
united in some and forming a column in the centre of the flower (Figs.
457, 458); _Xylophylla_ is a section of this genus.-- _Hura crepitans_
(Sand-box tree) has a many-carpellate gynœceum, which separates with
great violence when ripe.--A drupe is found in _Hippomane mancinella_
(the Mancinil-tree, W. Ind.)--_Alchornea (Coelebogyne) ilicifolia_ is
well known on account of its “parthenogenesis”; only the ♀-plant has
been introduced into Europe, but it nevertheless produces seeds capable
of germination; these have generally several embryos.
[Illustration: FIGS. 456–458.--_Phyllanthus (Xylophylla)
angustifolius._
FIG. 456.--Leaf-like branch with flowers (nat. size).