106 SEXUAL SELECTION. [Part II. 



fined to the male sex. From the small size of insects, we 

 are apt to undervalue their appearance. If we could im- 

 agine a male Chalcosoma (fig. 15) with its polished, bronzed 

 coat-of-mail, and vast complex horns, magnified to the 

 size of a horse or even of a dog, it would be one of the 

 most imposing animals in the world. 



The coloring of insects is a complex and obscure sub- 

 ject. When the male differs slightly from the female, 

 and neither is brilliantly colored, it is probable that the 

 two sexes have varied in a slightly different manner, with 

 the variations transmitted to the same sex, without any 

 benefit having been thus derived or evil suffered. When 

 the male is brilliantly colored and differs conspicuously 

 from the female, as with some dragon-flies and many but- 

 terflies, it is probable that he alone has been modified, and 

 that he owes his colors to sexual selection ; while the fe- 

 male has retained a primordial or very ancient type of 

 coloring, slightly modified by the agencies before explained, 

 and has therefore not been rendered obscure, at least in 

 most cases, for the sake of protection. But the female 

 alone has sometimes been colored brilliantly so as to imi- 

 tate other protected species inhabiting the same district. 

 When the sexes resemble each other and both are obscure- 

 ly colored, there is no doubt that they have been in a 

 multitude of cases colored for the sake of protection. So 

 it is in some instances when both are brightly colored, 

 causing them to resemble surrounding objects such as 

 flowers, or other protected species, or indirectly by giving 

 notice to their enemies that they are of an unpalatable 

 nature. In many other cases in which the sexes resemble 

 each other and are brilliantly colored, especially when the 

 colors are arranged for display, we may conclude that they 

 have been gained by the male sex as an attraction, and 

 have been transferred to both sexes. We are more es- 

 pecially led to this conclusion whenever the same type of 



