BUTTERFLIES AND MOTHS. 315 



Stunted males. The reverse appears to occur seldom; for, as he 

 believes, the more vigorous males pass over the weakly females, 

 and are attracted by those endowed with most vitality. Neverthe- 

 less, the Bombycidse, though obscurely-colored, are often beauti- 

 ful to our eyes from their elegant and mottled shades. 



I have as yet only referred to the species in which the males 

 are brighter colored than the females, and I have attributed 

 their beauty to the females for many generations having chosen 

 and paired with the more attractive males. But converse cases 

 occur, though rarely, in which the females are more brilliant 

 than the males; and here, as I believe, the males have selected 

 the more beautiful femajles, and have thus slowly added to their 

 beauty. We do not know why in various classes of animals the 

 males of some few species have selected the more beautiful fe- 

 males instead of having gladly accepted any female, as seems to 

 be the general rule in the animal kingdom; but if, contrary to 

 what generally occurs with the Lepidoptera, the females were 

 much more numerous than the males, the latter would be likely 

 to pick out the more beautiful females. Mr. Butler showed me 

 several species of Callidryas in the British Museum, in some of 

 which the females equalled, and in others greatly surpassed the 

 males in beauty; for the females alone have the borders of their 

 wings suffused with crimson and orange, and spotted with black. 

 The plainer males of these species closely resemble each other, 

 showing that here the females have been modified; whereas 

 in those cases, where the males are the more ornate, it is these 

 which have been modified, the females remaining closely alike. 



In England we have some analogous cases, though not so 

 marked. The females alone of two species of Thecla have a 

 bright-purple or orange patch on their fore-wings. In Hip- 

 parchia the sexes do not differ much; but it is the female of 

 H. janira which has a conspicuous light-brown patch on her 

 wings; and the females of some of the other sp;ecies are brighter 

 colored than their males. Again, the females of Colias edusa and 

 hyale have "orange or yellow spots on the black marginal border, 

 "represented in the males only by thin streaks;" and in Pieris 

 it is the females which "are ornamented with black spots on the 

 "fore-wings, and these are only partially present in the males." 

 Now the males of many butterflies are known to support the 

 females during their marriage flight; but in the species just 

 named it is the females which support the males; so that the 

 part which the two sexes play is reversed, as is their relative 

 beauty. Throughout the animal kingdom the males commonly 

 take the more active share in wooing, and their beauty seems 

 to have been increased by the females having accepted the more 

 attractive individuals; but with these butterflies, the females 

 lake the more active part in the final marriage ceremony, so 



