The Theory of Sex and Sexual Genesis. 673 
sperm-cell, in addition to changes in some of the external condi- 
_ tions here mentioned. And in sexual genesis there is the further 
difference that whatever advantage there is in crossing, or in the 
_ union of two portions of germinal matter derived from different 
| The Redundant Sexual Type—In the early stages of embryonic 
_ development in the higher animals no distinction as to sex is 
= -*pparent even in the sexual organs. Having regard to this fact, 
__ the view which had come to be generally accepted among physi- 
= Slogists, before the advent of Darwin's theory, with respect to 
4 the morphology of the sexes, was, that there is a common type 
a for all the individuals of both sexes in a species. But by most 
_ Physiologists this type was not believed to be hermaphroditic. 
_ “The early type of the sexual organs is to be regarded as com- 
mon and single rather than double, as some have considered it” 
{Allen Thomson, Todd's Cyclop., Vol. 11, 1839, Art. Generation). 
In the article on hermaphroditism in the same work, Simpson 
_ dpots, as he says, “the opinion commonly received by physiol- 
Ogists of the fundamental unity of sex among all individuals be- 
Mailat to the higher animals ; or, to express it otherwise, we have 
_ ‘sumed that each individual is, when normally formed originally 
| Padiments are the rudimentary mammz in male mammals and 
the clitoris in females 
_Whea Darwin adduced the existence of rudimentary organs as 
fidence in support of the theory of descent, and as facts that are 
= on any other theory, he made no distinction between 
tedimeatary sexual organs and rudiments of organs that pertain to 
_ sual self-maintenance. The only possible or reasonable 
nition of the existence of the latter is that they are reduced 
‘tation in 
s may, I think, be made. In the first place, none of the 
