40i THE DESCENT OF MAN 



semble each other in their general type of coloration; and 

 they likewise resemble both sexes of the species in several 

 allied genera, found in various parts of the world. Hence 

 we may infer that these nine species, and probably all the 

 others of the genus, are descended from an ancestral form 

 which was colored in nearly the same manner. In the tenth 

 species the female still retains the same general coloring, but 

 the male resembles her, so that he is colored in a much less 

 gaudy and contrasted manner than the males of the previous 

 species. In the eleventh and twelfth species the females de- 

 part from the usual type, for they are gayly decorated almost 

 like the males, but in a somewhat less degree. Hence in 

 these two latter species the bright colors of the males seem 

 to have been transferred to the females; while in the tenth 

 species the male has either retained or recovered the plain 

 colors of the female, as well as of the parent-form of the 

 genus. The sexes in these three cases have thus been ren- 

 dered nearly alike, though in an opposite manner. In the 

 allied genus Eubagis, both sexes of some of the species are 

 plain-colored and nearly alike; while with the greater num- 

 ber the males are decorated with beautiful metallic tints in 

 a diversified manner, and differ much from their females. 

 The females throughout the genus retain the same general 

 style of coloring, so that they resemble one another much 

 more closely than they resemble their own males. 



In the genus Papilio, all the species of the JEneas group 

 are remarkable for their conspicuous and strongly contrasted 

 colors, and they illustrate the frequent tendency to grada- 

 tion in the amount of difference between the sexes. In a 

 few species, for instance in P. ascanius, the males and 

 females are alike; in others the males are either a little 

 brighter or very much more superb than the females. The 

 genus Junonia, allied to our Vanessae, offers a nearly parallel 

 case, for although the sexes of most of the species resemble 

 each other, and are destitute of rich colors, yet in certain 

 species, as in J", oenone, the male is rather more bright- 

 colored than the female, and in a few (for instance J. an- 



