THE LIFE HISTORY OF FERNS 15 
heart, where the scale is obviously much thickened, there 1584: 
cluster of teat-shaped, projecting tubular bodies, called archegonia, 
and it is in these two kinds of bodies that we find what are essen- 
tially the flowers of the Fern, and it is through the conjunction 
of their contents that the young Fern is engendered. The rounded 
projections, termed the antheridia, contain a number of extremely 
minute, coiled-up organisms, termed antherozoids, and under 
proper conditions of moisture, which determines the presence of a 
dew-like drop of 
water adherent to 
the under-side of 
the scale, the an- 
theridium bursts, 
and the anthero- 
zoids, being freed, 
proceed to swim 
about actively by 
means of the motile 
cilia, or hairs, with 
which they are fur- 
nished. Atthis junc- 
ture the archegonia, 
clustered together 
as described, each | 
of which has an | 
incipient seed em- | 
bedded in the scale 
at its base, are pre- 
pared for fertiliza- 
tion, which is effect- 
ed by one of the — > 
antherozoids pass- | 
ing through it and | 
reaching the inci- == = = 
pient seed, which Fig. 6.—Further development of young Fern. 
then becomes prac- 
tically a seed proper, and eventually produces a young Fern, the 
scale acting as nurse by supplying nutrition at the outset, as a sort 
of substitute for the nourishment which is usually stored up in the 
seed itself with this object. It is a very remarkable fact that, 
minute as these antherozoids are, and truly vegetative as they 
must be, they obviously are not only endowed with locomotive 
power, but also with volition, since, when freely swimming, they 
will definitely travel towards a minute touch of malic acid applied 
to the scale, and it has been shown that the archegonia, when ready 
for fertilization, exude this acid, and thus attract the antherozoids 
in the right direction. 


A 



