676 The Theory of Sex and Sexual Genesis. 
would be for each female parent organism to produce two kinds 
of ova or germ-cells, one kind fitted to initiate the development 
of male, and the other the development of: female offspring, 
while each male parent organism produced two corresponding 
kinds of sperm-cells. The other way would be for only on 
kind of ova and one kind of sperm-cells to be produced ina 
species, but for each embryo to be deflected to a one-sided devel- 
opment—that of one of the sexes—so early and so completely 
that no perceptible rudiments of the sexual organs proper to the 
opposite sex should at any time be formed. The first method 5 
evidently too complicated ever to be established and maintained 
in any species by natural selection, at least without soa great 
advantage in the perpetuation of the species could be gained by 
it that could not be secured in any other way. The second 
method is actually exemplified in a great many of the lover 
monosexual organisms, where the requisite sexual oigan T 
simply of an ovary or pistil in the one sex and a testicle or ati 
in the other. In these no persistent rudiments of the orga ; 
the opposite sex are perceptible in individuals of either meer 
in the higner animals, where a complicated apparatus m oe 
correlation with the other parts of the body is required poe 
sex for the performance of its part of the reproductive 
so early and complete a deflection of the course of ee 4 
with respect to these organs, cannot take place. A 
sexual organs of the sexually redundant type must tural oo 
to a functional state in each sex; and the intimate stù y 
nection and functional coôrdination with the pra m jots, 
body demanded in the efficient performance ye F an cal 
makes it necessary that their development be ini ak: 
stage in the development of the embryo. pe = d the p 
great complexity can be evolved only on a -sod in the a 
a various 
he e ion—on condition that the s alasticilY: 
stages of the evolution—on time their plastic 
dered a5 
psd 
À 
rocesses, 
differentiation of the conditions of those P 
the development of the sexual organs, as een 
cause those organs that are functional in €t y 
only to enter upon a complete development, 
