218 SEXUAL DIVERSITY 



one sex and orange in the other ; nothing could be 

 simpler than this, and the distinction is so slight 

 it might be readily overlooked, yet it is the only 

 difference one can find, and there is nothing anal- 

 ogous to it in the allied species, the Painted Lady 

 (V. cardui). On the other hand, the two sexes of 

 the Spring Beauty (Erora laeta) have so different 

 an appearance that it is not strange that they were 

 originally described by the same person as two 

 distinct species ; and the difference is still more 

 marked in the Chrysophanini, where it may possi- 

 bly be said to affect also the pattern of coloration. 

 In one species, the Purple Disk (Epidemia epi- 

 xanthe), the female, besides lacking on its upper 

 surface the brilliant and peculiar lustre of the op- 

 posite sex, is also marked by the presence of a row 

 of blackish spots, which is quite wanting in the 

 male. In another, the Bronze Copper (Chryso- 

 phanus thoe), the male has the upper surface of 

 a deep coppery hue, with a narrow black border ; 

 while the female has a deep orange color with a 

 broad black margin and a transverse row of dis- 

 tinct black spots near the middle of the outer half 

 of the wing, which appear in the male only through 

 the diaphanous nature of the wings, the same row 

 occurring in both sexes upon the under surface. 



