THE CLASSIFICATION OF FOSSIL PLANTS 
which falls out of the spore capsule on the reverse side 
of the fern leaf, will germinate on moist soil and form 
an almost microscopically tiny plant, which contains fe¬ 
male sex organs, with egg cells in them, and male sex 
organs containing spermatozoa. The spermatozoon works 
its way to the egg and fertilizes it, and out of the fertilized 
egg cell develops ultimately a full-grown spore-bearing 
plant. The large ferns and fern-like plants that we see 
in the woods represent only the asexual, or spore-bearing, 
generation of the plant. 
The lower plants share with the animals, including 
man, the possession of these spermatozoa, which are mi¬ 
croscopically small bodies having motion of their own 
by means of fine appendices by which they propel them¬ 
selves until they reach the egg cells, which they penetrate. 
The spermatozoon combines with the nucleus of the egg 
cell to form an embryo, which gradually grows into a 
fully-developed organism. 
There is, as we know, a great waste of material in 
Nature. Millions of spermatozoa are sent out, but only 
a very few egg cells are fertilized. The substance of the 
spermatozoon is one of the most marvelous mechanisms 
known, for, although it is almost inconceivably small, it 
contains within it the potentiality for producing all the 
characteristics of the adult form. 
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