s reduced to small scales or
hairs. The flowers are usually surrounded by more or less dry leaves
(glumes, paleae) which are closely set, so as to nearly conceal the
flowers. The flowers are either hermaphrodite or unisexual.

[Illustration: FIG. 87.--Types of _Glumaceae_. _A_, a sedge, _Carex_
(_Cyperaceae_). [Male], the male; [Female], the female flowers, x 1/2.
_B_, a single male flower, x 2. _C_, a female flower, x 2. _D_,
fruiting spike of another _Carex_, x 1/2. _E_, a single fruit, x 1. _F_,
the same, with the outer envelope removed, and slightly enlarged. _G_,
section of _F_, x 3. _em._ the embryo. _H_, a bulrush, _Scirpus_
(_Cyperaceae_), x 1/2. _I_, a single spikelet, x 2. _J_, a single flower,
x 3. _K_, a spikelet of flowers of the common orchard grass,
_Dactylis_ (_Gramineae_), x 2. _L_, a single flower, x 2. _M_, the base
of a leaf, showing the split sheath encircling the stem, x 1. _N_,
section of a kernel of corn, showing the embryo (_em._), x 2.]

There are two well-marked families, the sedges (_Cyperaceae_) and the
grasses (_Gramineae_). The former have solid, often triangular stems,
and the sheath at the base of the leaves is not split. The commonest
genera are _Carex_ (Fig. 87, _A_, _G_) and _Cyperus_, of which there
are many common species, differing very little and hard to
distinguish. There are several common species of _Carex_ which blossom
early in the spring, the male flowers being quite conspicuous on
account of the large, yellow anthers. The female flowers are in
similar spikes lower down, where the pollen readily falls upon them,
and is caught by the long stigmas. In some other genera, _e.g._ the
bulrushes (_Scirpus_) (Fig. 87, _H_), the flowers are hermaphrodite,
_i.e._ contain both stamens and pistils. The fruit (Fig. 87, _F_) is
seed-like, but really includes the wall of the ovary as well, which is
grown closely to the enclosed seed. The embryo is small, surrounded by
abundant endosperm (Fig. 87, _G_). Very few of the sedges are of any
economic importance, though one, the papyrus of Egypt, was formerly
much valued for its pith, which was manufactured into paper.

The second family, the grasses, on the contrary, includes the most
important of all food plants, all of the grains belonging here. They
differ mainly from the sedges in having, generally, hollow,
cylindrical stems, and the sheath of the leaves split down one side;
the leaves are in two rows, while those of the sedges are in thre