Chap. XL] BUTTERFLIES AND MOTHS. 377 



nearly the same manner as the males, but in a somewhat 

 less degree. Hence in these two species the bright colors 

 of the males seem to have been transferred to the females ; 

 while the male of the tenth species has either retained or 

 recovered the plain colors of tlie female as well as of the 

 parent-form of the genns ; the two sexes being thus ren- 

 dered in both cases, though in an opposite manner, nearly 

 alike. In the allied genus Eubagis, both sexes of some of 

 the species are plain-colored and nearly alike ; while with 

 the greater number the males are decorated with beauti- 

 ful metallic tints, in a diversified manner, and differ much 

 from their females. The females throughout the genus re- 

 tain the same general style of coloring, so that they com- 

 monly resemble each other much more closely than they 

 resemble their own proper males. 



In the genus Papilio, all the species of the ^neas 

 group are remarkable for their conspicuous and strongly- 

 contrasted colors, and they illustrate the frequent ten- 

 dency to gradation 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 

 a little or very much more superbly colored than the fe- 

 males. The genus Junonia, allied to our Vanessoo, offers a 

 nearly parallel case, for although the sexes of most of the 

 species resemble each other and are destitute of rich col- 

 ors, yet in certain species, as in Jl oeno7ie, the male is 

 rather more brightly colored than the female, and in a few 

 (for instance, J[ andreinia^d) the male is so different from 

 the female that he might be mistaken for an entirely dis- 

 tmct species. 



Another striking case was pointed out to me in the 

 British Museum by Mr. A. Butler, namely, one of the 

 Tropical American Thecla?, in which both sexes are nearly 

 alike and wonderfully splendid; in another, the male is 

 colored in a similai-ly gorgeous manner, while the whole 

 17 



