CHAPTER III 
REPRODUCTION AND PROPAGATION 
The spore is the natural reproductive organ of the fern, 
and its method of development is most curious and interesting, 
though difficult to examine on account of its small size. When 
released by the bursting of the capsule, it floats in the air until 
some damp spot is reached, when growth at once commences, 
and in two weeks the small green growth may be detected 
without the magnifying glass, and, if given suitable conditions, 
it continues to grow on till about half-an-inch long and wide, 
by which time it will have assumed the two-lobed shape 
shown in the young plant of Pteris cretica, figured (Plate 1 2 6 , c). 
At that stage it is termed the prothallus , and looks like 
a green lichen or liverwort, attached by minute hair-like roots 
to the ground. Its growth then ceases, but, if very carefully 
examined under a powerful microscope, a few small tubercles 
may be seen on the under side, just below the notch, and 
those who make this a special study will find that male and 
female organs are there produced, and that sexual fertilisation 
is accomplished by them. 
The male organs (. Antheridia ) usually occur among the 
root hairs near the base of the prothallus, and each consists 
of a raised cell containing numerous smaller cells, each of 
which contains a spiral body known as a spermatozoid, crowned 
with a brush of fine cilia at the smaller end. When mature 
the wall of the main cell disappears, and if a drop of water 
comes in contact with the minute inner cells these also burst, 
and the spermatozoids begin an active motion through the 
water, the ciliated end going first. 
