ANTIGENY; OR SEXUAL DIVERSITY. 533 



moths, in which the hind wings are covered by the front wings in 

 ropt)se, and are as a rule less ornamented by diverse patterns. We might 

 perhaps anticipate tlie restriction of the characteristics to the fore wings, 

 since upon the upper surface the complication of colorational design is 

 greater in buttertiies on these than on tiie hind wings ; yet this same 

 reasoning makes their restriction to the upper surface the more striking, 

 since the under surface of the liind wings of butterflies is usually more 

 variegated than any other part. 



Xow in all these cases of colorational antigeny, it is the female and al- 

 most never tlie male, which first departs from the normal type of coloring 

 of the group to which the species belongs. Occasionally the feminine 

 peculiarity has been transmitted to the male, and, by this means, a new 

 type of coloration established in the group ; but I recall among our but- 

 terflies but one* case where the male alone departs from the general tyj)e 

 of coloring peculiar to the group. This is precisely the opposite conclu- 

 sion to that wliich Darwin reached. He gives several examples on the 

 authority of Bates, which certainly favor his conclusion, but may, at the 

 same time, be explained from the opposite point of view. He gives other 

 examples from the European blue butterflies, which not only do not sup- 

 port, but even oppose, his general statement. 



Take the case of Semn. diana, than which we could hardly find a 

 stronger, since the group (Argynnidi) to which it belongs is remarkably 

 uniform, exhibiting in all its numerous members the same characteristic 

 play of fulvous and black markings. The male of S. diana is indeed very 

 unlike most other fritillaries, but it retains, nevertheless, abundant traces 

 of the same style of ornamentation, and has precisely the same colors ; 

 while the female departs widely from the characteristic features of orna- 

 mentation in the group, and in addition, loses every trace of fulvous, so 

 that no one at first glance would recognize it as a member of the Argynnidi. 

 Or, if it be objected that a case of variation through mimicry should not be 

 used here, take Eurymus philodice, and its allies. In some Eurymi, indeed, 

 there are only pale females ; but in others all, or most of the females, are 

 yellow or orange, like the males : and any one who knows how yellow and 

 orange tints prevail throughout the group of Rhodoceridi will acknowledge 

 that the color of the males is normal. So, too, with the blues (Lycaenidi), 

 which Darwin himself quotes: in almost all of them, both males and 

 females are of some shade of blue; in comparatively few, the males are 

 blue and the females brown ; in exceedingly few, both sexes are brown : 

 and the very fact that tliey are familiarly known as "blues" is a popular 

 recognition of the prevailing color. In the group of skippers to which 

 Thymelicus brettus belongs (Pamphilidi), the prevailing colors, at least in 



* Cj'aiiiris pseiulargioliis, in wbich both face, but in the south the male i:< souictimes 

 sexes are ordinarily blue upon the upper sur- brown. 



