CHAPTER VII 
THE GERM CELLS OF HERMAPHRODITIC ANIMALS 
Many of the most interesting biological problems 
are those connected with the phenomenon of sex. 
The term “‘sex”’ is applied to the soma or body of an 
organism; it indicates the presence of certain mor- 
phological and physiological characteristics, which 
may be separated into primary and secondary sexual 
characters. The primary sexual characters are those 
immediately connected with the reproductive organs ; 
the secondary sexual characters, such as the beard of 
man, the brilliant feathers and beautiful songs of 
many male birds, and the antlers of the moose, repre- 
sent differences between male and female individuals 
not directly concerned with the production of germ 
cells. It is customary to speak of male germ cells 
and female germ cells; this is not strictly proper, 
since in only a few special cases can we predict the 
sex of the individual which will develop from an egg. 
Moreover, every germ cell must contain the poten- 
tiality of both sexes since sooner or later its descend- 
ants will give rise, some to male, some to female or 
perhaps to hermaphroditic offspring. Thus the egg 
is an initial hermaphrodite; it may or may not be- 
come an eventual hermaphrodite according to the sex- 
ual condition of the individual to which it gives rise. 
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