TABOO AND GENETICS 27 



The bodily peculiarities of each sex, as 

 distinguished from the sex-glands or gonads 

 themselves, are known as secondary sex 

 characters. To put our statement in the para- 

 graph above in another form, the primary and 

 secondary sex do not always correspond in all 

 details. We shall find as we proceed that our 

 original tentative definition of sex as the ability 

 to produce in the one case sperm, in the other 

 eggs, is sometimes difficult to apply. What 

 shall we say of a sterile individual, which 

 produces neither ? The problem is especially 

 embarrassing when the primary and secondary 

 sex do not correspond, as is sometimes the case. 



Even in a fully grown animal, to remove or 

 exchange the sex glands (by surgery) modifies 

 the bodily type. One of the most familiar 

 cases of removal is the gelding or desexed horse. 

 His appearance and disposition are different 

 from the stallion, especially if the operation 

 takes place while he is very young. The reason 

 he resembles a normal male in many respects 

 is simply that sexuality in such highly-organized 

 mammals is of the whole body, not of the sex- 

 glands or organs alone. 



Suppose this horse was desexed at two years 

 old. Nearly three years had elapsed since he 

 was a fertilized egg. During the eleven months 

 or so he spent within his mother, he developed 

 a very complicated body. Beginning as a male, 



