406 SEXUAL SELECTION. Part II. 



attention of their enemies. But we are concerned 

 with the effects of the destruction or preservation of 

 certain individuals of either sex, on the character of 

 the race. With insects, after the male has fertilised 

 the female, and after the latter has laid her eggs, 

 the greater or less immunity from danger of either sex 

 could not possibly have any effect on the offspring. 

 Before the sexes have performed their proper functions, 

 if they existed in equal numbers and if they strictly 

 paired (all other circumstances being the same), the 

 preservation of the males and females would be equally 

 important for the existence of the species and for the 

 character of the offspring. But with most animals, as 

 is known to be the case with the domestic silk-moth, 

 the male can fertilise two or three females ; so that the 

 destruction of the males would not be so injurious to 

 the species as that of the females. On the other hand, 

 Dr. Wallace believes that with moths the progeny from 

 a second or third fertilisation is apt to be weakly, and 

 therefore would not have so good chance of surviving. 

 When the males exist in much greater numbers than the 

 females, no doubt many males might be destroyed with 

 impunity to the species ; but I cannot see that the 

 results of ordinary selection for the sake of protection 

 would be influenced by the sexes existing in unequal 

 numbers ; for the same proportion of the more con- 

 spicuous individuals, whether males or females, would 

 probably be destroyed. If indeed the males presented 

 a greater range of variation in colour, the result would 

 be different ; but we need not here follow^ out such com- 

 plex details. On the whole I cannot perceive that an 

 inequality in the numbers of the two sexes would in- 

 fluence in any marked manner the effects of ordinary 

 selection on the character of the offspring. 



Female Lepidoptera require, as Mr. Wallace insists, 



