y for a day or two, are teased out in a drop of water, they
will quickly open at the apex, the whole mass of sperm cells being
discharged at once.

Among the antheridia are borne peculiar hairs (Fig. 59, _p_) tipped
by a large globular cell.

[Illustration: FIG. 61.--_A_, _B_, young; _C_, nearly ripe archegonium
of _Funaria_, optical section, x 150. _D_, upper part of the neck of
_C_, seen from without, showing how it is twisted. _E_, base of a ripe
archegonium. _F_, open apex of the same, x 150. _o_, egg cell. _b_,
ventral canal cell.]

Owing to their small size the spermatozoids are difficult to see
satisfactorily and other mosses (_e.g._ peat mosses, Figure 64, the
hairy cap moss, Figure 65, _I_), are preferable where obtainable.
The spermatozoids of a peat moss are shown in Figure 60, _D_. Like
all of the bryophytes they have but two cilia.

The archegonia (Fig. 61) should be looked for in the younger plants
in the neighborhood of those that bear capsules. Like the antheridia
they occur in groups. They closely resemble those of the liverworts,
but the neck is longer and twisted and the base more massive.
Usually but a single one of the group is fertilized.

[Illustration: FIG. 62.--_A_, young embryo of _Funaria_, still
enclosed within the base of the archegonium, x 300. _B_, an older
embryo freed from the archegonium, x 150. _a_, the apical cell.]

To study the first division of the embryo, it is usually necessary
to render the archegonium transparent, which may be done by using a
little caustic potash; or letting it lie for a few hours in dilute
glycerine will sometimes suffice. If potash is used it must be
thoroughly washed away, by drawing pure water under the cover glass
with a bit of blotting paper, until every trace of the potash is
removed. The first wall in the embryo is nearly at right angles to
the axis of the archegonium and divides the egg cell into nearly
equal parts. This is followed by nearly vertical walls in each cell
(Fig. 62, _A_). Very soon a two-sided apical cell (Fig. 62, _B_,
_a_) is formed in the upper half of the embryo, which persists until
the embryo has reached a considerable size. As in the liverworts the
young embryo is completely covered by the growing archegonium wall.

The embryo may be readily removed from the archegonium by adding a
little potash to the water in which it is lying, allowing it to
remain for a few mo